Physics Letters B 725 (2013) 36–59
Contents lists available at SciVerse ScienceDirect

Physics Letters B

www.elsevier.com/locate/physletb

Searches for Higgs bosons in pp collisions at
√

s = 7 and 8 TeV
in the context of four-generation and fermiophobic models ✩

.CMS Collaboration �

CERN, Switzerland

a r t i c l e i n f o a b s t r a c t

Article history:
Received 7 February 2013
Received in revised form 11 June 2013
Accepted 19 June 2013
Available online 1 July 2013
Editor: M. Doser

Keywords:
CMS
Physics
Higgs

Searches are reported for Higgs bosons in the context of either the standard model extended to include
a fourth generation of fermions (SM4) with masses of up to 600 GeV or fermiophobic models. For
the former, results from three decay modes (ττ , WW, and ZZ) are combined, whilst for the latter
the diphoton decay is exploited. The analysed proton–proton collision data correspond to integrated
luminosities of up to 5.1 fb−1 at 7 TeV and up to 5.3 fb−1 at 8 TeV. The observed results exclude the
SM4 Higgs boson in the mass range 110–600 GeV at 99% confidence level (CL), and in the mass range
110–560 GeV at 99.9% CL. A fermiophobic Higgs boson is excluded in the mass range 110–147 GeV at
95% CL, and in the range 110–133 GeV at 99% CL. The recently observed boson with a mass near 125 GeV
is not consistent with either an SM4 or a fermiophobic Higgs boson.

© 2013 CERN. Published by Elsevier B.V. All rights reserved.
1. Introduction

In the standard model (SM) [1–3], electroweak symmetry
breaking is achieved by introducing a complex scalar doublet,
leading to the prediction of the Higgs boson (H) [4–9]. Precision
electroweak measurements indirectly constrain the SM Higgs bo-
son mass mH to be less than 158 GeV [10]. The direct experimental
searches exclude at 95% confidence level (CL) the SM Higgs boson
in the mass range up to 600 GeV, except for the mass window
122–128 GeV [11–14], where a new particle with a mass near
125 GeV was recently observed in a combination of searches tar-
geting SM Higgs boson decay modes [13,14].

Various extensions of the standard model have been proposed,
such as the inclusion of a fourth generation of fermions (the SM4
model) [15–19] or models with multiple Higgs bosons and mod-
ified couplings such that one of the Higgs bosons couples only
to vector bosons at tree level (the fermiophobic, FP, benchmark
model) [20–25]. Both types of model have a major impact on
Higgs phenomenology. In the SM4 context for example, constraints
from electroweak data become less restrictive, allowing the mass
range 115–750 GeV at 95% CL, as long as the mass splitting in the
fourth generation is O(50) GeV [17]. Likewise Higgs boson pro-
duction cross sections and decay branching fractions are strongly
affected in both scenarios. Therefore, the conclusions regarding the
existence (or not) of a Higgs boson based on direct searches that
assume the SM are not valid in SM4 or FP scenarios without a

✩ © CERN for the benefit of the CMS Collaboration.
� E-mail address: cms-publication-committee-chair@cern.ch.

proper re-interpretation. Given that the nature of the new boson
near 125 GeV has yet to be determined definitively, it is appropri-
ate to test alternative interpretations beyond the standard model.

To date, the direct searches for the SM4 Higgs boson have ex-
cluded at 95% CL the mass range 121–232 GeV [26–28]. Previous
searches using the diphoton decay at the LEP collider [29], the
Tevatron collider [26], and the Large Hadron Collider (LHC) [30] ex-
clude a fermiophobic Higgs boson lighter than 121 GeV at 95% CL.
Using a combination of decay modes, searches at the LHC [31]
have ruled out a fermiophobic Higgs boson in the mass range
110–194 GeV at 95% CL; the range 110–188 GeV is excluded at
99% CL, with the exception of two gaps from 124.5–127 GeV and
from 147.5–155 GeV.

In this Letter, we re-interpret and combine the SM Higgs boson
searches [13,32–34], carried out by the Compact Muon Solenoid
(CMS) experiment [35] at the LHC, in the SM4 context. The search
is performed in the mass range 110–600 GeV. We also report
on a search for a fermiophobic Higgs boson in the mass range
110–150 GeV, in the γ γ decay mode. The analysed proton–
proton collision data correspond to integrated luminosities of up
to 5.1 fb−1 at 7 TeV and up to 5.3 fb−1 at 8 TeV.

2. The SM4 and FP models

The presence of fourth-generation fermions would have a sig-
nificant impact on the effective couplings of the Higgs boson to the
SM particles and, thus, directly affect the Higgs boson production
cross sections and decay branching fractions. Since the couplings
of the Higgs boson to fermions are proportional to their masses,

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CMS Collaboration / Physics Letters B 725 (2013) 36–59 37

the electroweak loop corrections with fourth-generation fermions
have a non-vanishing effect even for arbitrarily heavy fermions,
although perturbative calculations become unreliable for fermion
masses larger than 600 GeV.

In this analysis, we use the SM4 benchmark recommended by
the LHC Higgs cross section group in Ref. [36]: m�4 = mν4 = md4 =
600 GeV and mu4 − md4 = (50 + 10 · ln(mH/115)) GeV. Here m�4

and mν4 are the masses of the 4th generation charged lepton and
neutrino, while mu4 and md4 are the masses of the 4th generation
“up” and “down” quarks. These masses are not excluded by the di-
rect searches for heavy fermions [37–40] and still allow for pertur-
bative calculations. The SM4 Higgs boson cross sections and decay
branching fractions used in this analysis include electroweak next-
to-leading order (NLO) corrections [41,42]. The next-to-NLO order
QCD corrections are taken from Ref. [43]. Below we summarise the
effect of the fourth generation fermions, with the specified masses,
on the production and decay of an SM4 Higgs boson compared
with the SM Higgs boson of the same mass.

The square of the effective coupling of an SM4 Higgs boson to
gluons (g) is increased by a factor Kgg(mH) that ranges between
nine and four for a Higgs boson mass that ranges from 110 to
600 GeV. This enhancement results from the inclusion of u4 and
d4 quarks in the quark loop diagrams associated with the H → gg
and gg → H processes. The square of the effective coupling of an
SM4 Higgs boson to W and Z vector bosons (henceforth referred
to collectively as V bosons) becomes about three times smaller,
K V V (mH) ∼ 0.3, as the amplitudes of the NLO and leading order
(LO) contributions are of opposite signs in this case. A coinciden-
tal cancellation of the contributions from W bosons and heavy
fermions (top, u4, d4, �4) to the loop diagrams responsible for the
H → γ γ decay suppresses the square of the effective coupling to
photons by O(100). The squares of the fermionic ( f ) couplings are
enhanced by a factor K f f (mH) ∼ 1.6.

The enhancement in the effective couplings to gluons and the
suppression of couplings to vector bosons causes gluon fusion
production to dominate over the vector boson fusion (VBF) and
associated (VH) production mechanisms. Hence, the last two pro-
cesses can be neglected in searches for SM4 Higgs bosons, and
are ignored in the search presented in this Letter. The contribu-
tion from gluon fusion is rescaled by the SM4/SM mH-dependent
factor Kgg(mH) mentioned above. The H → bb search channel that
fully relies on associated production is not included in this combi-
nation. For simplicity, H → bb is denoted as H → bb, H → τ+τ−
as H → ττ , etc. Following Ref. [36], the uncertainties on the gluon
fusion cross section for the SM4 model are assumed to be the
same as for the SM Higgs boson and are taken from Ref. [44]. The
change in the Higgs boson decay partial widths modifies the decay
branching fractions as follows. The branching fraction B(H → γ γ )

is suppressed by O(100) with respect to the standard model. The
branching fractions B(H → WW) and B(H → ZZ) are suppressed
by approximately a factor of five for low Higgs boson masses for
which the WW and ZZ partial widths are not dominant. They re-
main almost unchanged in the mid-range around mH ∼ 200 GeV,
where vector boson partial widths are the main contributors to the
total width Γtot, and are about 60% of the SM Higgs boson values
above mH ∼ 350 GeV after the H → tt decay channel opens up. The
branching fraction B(H → ττ ) is affected only slightly, O(20%), in
the mass range where this decay mode is used. The total width
of the SM4 Higgs boson at high masses, where it is relevant for
the H → ZZ → 4� (where � denotes an electron or a muon) search,
is about 30–50% of the SM Higgs width, depending on the Higgs
boson mass.

Since the H → γ γ channel is so strongly suppressed, it has
nearly no sensitivity for the SM4 Higgs boson and is therefore not
included in the combination. We explicitly checked that including

or omitting this channel has no effect on the combined SM4 Higgs
boson search results even in the presence of the significant excess
near 125 GeV observed in the standalone search for H → γ γ [13].

The theoretical uncertainties on the SM4 Higgs boson decay
branching fractions are derived from three independent sources
of relative uncertainty on the partial widths, which amount to
approximately 50%, 10%, and 5% for ΓV V , Γ f f , and Γgg, respec-
tively [36]. Any given decay channel H → xx is affected by each
of these three uncertainties. Using the equation Bxx = Γxx/Γtot and
standard error propagation, we translate the uncertainties on the
partial widths into uncertainties on the branching fractions of the
decay modes (ττ , WW, ZZ) used in this combination. The signal
acceptance for each exclusive final state is assumed to be the same
as reported in previous SM Higgs boson searches [13,32–34].

As a fermiophobic Higgs boson does not couple to fermions,
gluon fusion production becomes negligible, while the VBF and
VH production cross sections remain unchanged. Direct decays to
fermion pairs become impossible, which significantly increases the
branching fractions B(H → γ γ ), B(H → WW) and B(H → ZZ).
The diphoton decays are enhanced further as the negative inter-
ference between the W and top loops responsible for this decay
in the SM is no longer present. For a low mass FP Higgs bo-
son (mH ≈ 125 GeV) the decay to two photons is enhanced by
an order of magnitude with respect to the SM [23–25], and this
compensates for the reduced production cross section, keeping the
overall diphoton signal rate very similar to that in the SM. Produc-
tion cross sections and decay branching fractions, together with
their uncertainties, are taken from Ref. [44] and are derived from
Refs. [45–50].

3. The CMS detector and event reconstruction

The CMS apparatus [35] consists of a barrel assembly and two
endcaps, comprising, in successive layers outwards from the colli-
sion region, the silicon pixel and strip tracker, the lead tungstate
crystal electromagnetic calorimeter (ECAL), the brass/scintilla-
tor hadron calorimeter, the superconducting solenoid, and gas-
ionization chambers embedded in the steel flux return yoke for
the detection of muons. The polar coordinate system (θ , φ) is used
to describe the direction of particles and jets emerging from the
pp collisions, where θ is the polar angle measured from the pos-
itive z axis (along the anticlockwise beam direction) and φ is the
azimuthal angle. The pseudorapidity, defined as η = − ln[tan(θ/2)],
is commonly used in place of θ .

Particles are reconstructed with the CMS “particle-flow” event
description [51,52] using an optimised combination of all sub-
detector information to form “particle-flow objects”: electrons,
muons, photons, charged and neutral hadrons. Jets are formed by
clustering these objects with the anti-kT algorithm [53] using a
distance parameter �R = 0.5, where �R = √

(�η)2 + (�φ)2 and
�η and �φ are the pseudorapidity and azimuthal angle differ-
ences between the jet axis and the particle direction. The missing
transverse energy vector, �Emiss

T , is taken as the negative vector sum
of all particle transverse momenta, and its magnitude is referred to
as Emiss

T .

4. Search channels

4.1. The SM4 search channels

The SM4 results presented are obtained by combining searches
in the individual Higgs boson decay channels listed in Table 1.
The table summarises the main characteristics of these searches,
namely: the mass range of the search, the integrated luminosity



38 CMS Collaboration / Physics Letters B 725 (2013) 36–59
Table 1
Summary of the analyses included in the SM4 combination.

Channel mH range (GeV) Int. lumi. (fb−1) Sub-channels mH resolution Ref.

7 TeV 8 TeV

H → ττ → eτh/μτh/eμ/μμ 110–145 4.9 5.1 16 20% [13]
H → WW → 2�2ν 110–600 4.9 5.1 4 20% [13,32]
H → ZZ → 4� 110–600 5.0 5.3 3 1–2% [13]
H → ZZ → 2�2ν 250–600 4.9 – 2 7% [33]

H → ZZ → 2�2q

{
130–164
200–600

4.9 – 6
3%
3%

[34]
used, the number of exclusive sub-channels, and the approximate
instrumental mass resolution.

Below we give a brief summary of the individual searches. More
detailed descriptions of all analyses can be found in Refs. [13,
32–34]. In the combination presented here, Higgs boson produc-
tion via VBF is neglected, and thus sub-channels in the H → ττ
and H → WW decay channels that explicitly target VBF production
are also dropped.

The H → ττ search [13] is performed using the final-state sig-
natures eμ, μμ, eτh, and μτh, where electrons and muons arise
from leptonic τ decays and τh denotes hadronic τ decays. Each of
these categories is further divided into 4 exclusive sub-categories
based on the jet multiplicity and transverse momentum (pT) of the
visible tau lepton decay. In each category, we search for a broad
excess in the reconstructed ττ mass distribution. The main irre-
ducible background, Z → ττ production, and the largest reducible
backgrounds (W + jets, multijet production, Z → ee) are evaluated
from various control samples in data.

The H → WW → 2�2ν analysis [13,32] searches for an ex-
cess of events with two leptons of opposite charge, large missing
transverse energy Emiss

T , and less than two jets. Events are di-
vided into four categories, with different background compositions
and signal-to-background ratios, according to the number of jets
and whether the leptons are of the same or different flavour. For
events with no jets, the main background stems from non-resonant
WW production; for events with one jet, the dominant back-
grounds are from WW and top-quark production. The events are
split into same-flavour and different-flavour dilepton sub-channels,
since the background from Drell–Yan production is much larger
for the same-flavour dilepton events. To improve the separation of
signal from background in the 7 TeV analysis, multivariate analysis
classifiers are trained for a number of Higgs boson masses, and a
search is made for an excess of events in the output distributions
of the classifiers. All background rates, except for small expected
contributions from WZ, ZZ, and Wγ , are evaluated from data.

In the H → ZZ → 4� channel [13], we search for a four-lepton
mass peak over a small continuum background. To separate sig-
nal and background, we use a discriminant calculated for each
event as the ratio of the respective probability densities for sig-
nal and background to form an event with the observed kinematic
configuration of four leptons. The 4e, 4μ, and 2e2μ sub-channels
are analysed separately since there are differences in the four-
lepton mass resolutions and the background rates arising from
jets misidentified as leptons. The dominant irreducible background
in this channel is from non-resonant ZZ production with both
Z bosons decaying to either 2e, 2μ, or 2τ (with the tau lep-
tons decaying leptonically) and is estimated from simulation. The
smaller reducible backgrounds with jets misidentified as leptons,
e.g. Z + jets, are estimated from data.

In the H → ZZ → 2�2ν search [33], we select events with a
lepton pair (e+e− or μ+μ−), with invariant mass consistent with
that of an on-shell Z boson, and a large missing transverse energy.
We then define a transverse invariant mass mT from the dilepton
momenta and �Emiss

T , which is assumed to originate from neutrinos

in the Z → νν decays, and search for a broad excess of events in
the mT distribution. The ZZ and WZ backgrounds are taken from
simulation, while all other backgrounds, Z + jets and a cumulative
sum of the rest, are evaluated from control samples in data.

In the H → ZZ → 2�2q search [34], we select events with two
oppositely-charged leptons (e+e− or μ+μ−), and two jets. The
two leptons and the two jets are required to have invariant masses
consistent with that of on-shell Z bosons. The events are cate-
gorised by the lepton flavour and the number of jets identified as
coming from the decay of a b-quark, thus defining six exclusive fi-
nal states. We search for a peak in the invariant mass distribution
of the dilepton–dijet system, with the background rate and shape
estimated using control regions in data.

4.2. The FP search channels

In this section, we describe the FP Higgs boson search with
the 8 TeV dataset. We use the H → γ γ decay mode and ex-
ploit the characteristic signatures associated with the VBF and VH
processes: namely, the two forward jets produced by the scat-
tered quarks in VBF production and charged leptons (electrons or
muons) or large missing transverse energy induced by neutrinos,
both coming from vector boson decays in VH production. The FP
Higgs boson search in the diphoton decay mode with the 7 TeV
dataset is described elsewhere [31].

The simulated VBF signal samples are generated with powheg

[54]. The difference in the event selection acceptance for samples
generated with powheg at NLO and with pythia [55] at LO is taken
as a systematic uncertainty, which is found to have a negligible im-
pact on the final results. The simulated VH samples are generated
with pythia.

Nine exclusive classes are defined. All require two, isolated,
high pT photons. Five of the nine require an additional tag: ei-
ther a pair of jets (subdivided into two sub-classes with low and
high dijet invariant masses, m jj), or an isolated lepton (subdivided
into e and μ sub-classes), or a large missing transverse energy.
The remaining diphoton events failing to pass VBF and VH pro-
duction tags form an untagged category, which is divided into four
sub-classes according to the photon shower shape and position in
the detector [13]. The selection criteria for the photon candidates
are the same as in the SM search [13] except for the modifications
noted below. A Higgs boson produced via the VBF or VH mecha-
nisms typically has a larger pT than a Higgs boson produced via
gluon fusion (which dominates SM Higgs production) and hence
the photon pT thresholds are increased. Furthermore, such photons
also have a harder transverse momentum spectrum than those of
photons produced by background processes [56] and thus signif-
icant separation of signal and background can be achieved. The
transverse momentum of the photon pair (pγ γ

T ) together with
their invariant mass (mγ γ ) are included in a two-dimensional un-
binned maximum likelihood. The signal and background models,
which are used to extract limits on the signal cross section, are
described in detail in Ref. [31]. The dijet-tagged class has the
greatest sensitivity; here the background model is derived from



CMS Collaboration / Physics Letters B 725 (2013) 36–59 39
Table 2
Number of selected events in the γ γ event classes, for data in the mass range 100–180 GeV and for a fermiophobic Higgs boson signal (mH = 125 GeV). The expected
number of background events in the signal region 120–130 GeV obtained from the fit of the data in the full mass range 100–180 GeV and the mass resolution for the
125 GeV FP Higgs boson signal in each event class are also given. All numbers are for the 8 TeV dataset.

Emiss
T tag Dijet high m jj Dijet low m jj Lepton tag (e,μ) Untagged

(a) (b) (c) (d)

Data 41 84 271 30 4992 9546 5105 8574
Signal (mH = 125 GeV) 2.3 14 10 3.5 18 23 12 14
Expected background 5.8 17 40 4.1 740 1400 760 1300

σeff (GeV) 2.0 2.1 2.2 2.1 1.5 2.0 3.8 3.9
data, by fitting the diphoton mass distributions over the range
100 < mγ γ < 180 GeV.

In the dijet-tagged classes the photon pT thresholds are raised
(compared with the SM search [13]) to pγ

T (1) > mγ γ /2, and
pγ

T (2) > 25 GeV, where pγ
T (1) and pγ

T (2) are the transverse mo-
menta of the leading and sub-leading photons respectively. The pT
thresholds for the two jets are 30 GeV and 20 GeV, and their sep-
aration in η must be greater than 3.0. The dijet mass is required
to be greater than 250 GeV. The selected events are subdivided
into two regions 250 < m jj < 500 GeV and m jj > 500 GeV, based
on the amount of background contamination as a function of dijet
mass. In addition, for events with m jj > 500 GeV, the pT threshold
for the subleading jet is raised to 30 GeV. Two additional selec-
tion criteria, relating the dijet and diphoton systems, are applied
to all selected events. The difference between the average η of the
two jets and the η of the diphoton system is required to be less
than 2.5 [57]. The difference in φ between the diphoton and dijet
systems is required to be greater than 2.6 radians.

In the lepton-tagged channel, which targets VH production, the
pT thresholds are again altered; values of pγ

T (1) > 3 × mγ γ /8, and
pγ

T (2) > 25 GeV are set. Separate muon and electron sub-classes
are defined, with at least one muon (electron) with pT > 20 GeV
and within |η| < 2.4 (|η| < 2.5) required. The leptons must be
isolated, using isolation criteria similar to those used for pho-
tons, and separated from the photons by �R > 1. To protect
against background events that arise from an electron misidenti-
fied as a photon in the Z → ee process, the mass of the photon–
electron system must differ from the Z boson mass by at least
5 GeV.

A significant fraction of events from VH production contains
large missing transverse energy due to the neutrinos from Z → νν
decays. Events that passed the requirements of the lepton-tag
channel are excluded to form a statistically independent Emiss

T -tag
class. The Emiss

T is required to be larger than 70 GeV. The photon
pT threshold requirements are the same as for the lepton-tag class.
Due to the negligible contribution of photons at large pseudorapid-
ity to the expected exclusion limit, only photons falling within the
ECAL barrel are kept (|η| < 1.48).

A substantial fraction of the FP signal events are not expected
to pass any of the previous tags, and so the remaining untagged
events are also exploited. Photon pT requirements of pγ

T (1) >

mγ γ /3, pγ
T (2) > mγ γ /4 and pγ γ

T /mγ γ > 0.1 are applied. The se-
lected events are divided into four classes according to the ex-
pected mass resolution and amount of background contamination
[13]. Two classifiers are used: the minimum R9 of the two pho-
tons, Rmin

9 , and the maximum absolute pseudorapidity of the two
photons. The quantity R9 is defined as the sum of the energy
in the 3 × 3 crystal array centred on the crystal with the max-
imum energy deposit divided by the total clustered energy, and
is designed to identify photons undergoing a conversion. The un-
tagged diphoton event classes are: (a) both photons in the barrel
and Rmin

9 > 0.94, (b) both photons in the barrel and Rmin
9 < 0.94,

(c) one or both photons in the endcaps and Rmin
9 > 0.94, and

(d) one or both photons in the endcaps and Rmin
9 < 0.94.

The numbers of events in the γ γ event classes are shown in
Table 2, for simulated signal events and for data. A Higgs boson
with mH = 125 GeV is chosen for the signal, and the data are
counted in the mass range 100–180 GeV. The table also shows the
mass resolution, σeff, defined as half the width of the narrowest
window containing 68.3% of the distribution.

5. Combination method

The combination of the Higgs boson searches, be it across dif-
ferent sub-channels within a given decay mode or across different
decay modes, requires simultaneous analysis of the data selected
by all individual analyses, accounting for all statistical and sys-
tematic uncertainties and their correlations. The overall statisti-
cal methodology used in this combination was developed by the
ATLAS and CMS Collaborations in the context of the LHC Higgs
Combination Group. The description of the general methodology
can be found in Refs. [58,59]. Below we give concise definitions of
statistical quantities we use for characterising the outcome of the
search. Results presented in this Letter are obtained using asymp-
totic formulae [60], including a few updates recently introduced in
the RooStats package [61].

For calculations of exclusion limits, we adopt the modified fre-
quentist criterion CLs [62,63]. The chosen test statistic, qμ , used to
determine how signal- or background-like the data are, is based
on the profile likelihood ratio. Systematic uncertainties are incor-
porated in the analysis via nuisance parameters and are treated
according to the frequentist paradigm. The profile likelihood ratio
is defined as

qμ = −2 ln
L(obs | μ · s + b, θ̂μ)

L(obs | μ̂ · s + b, θ̂ )
, (1)

where s stands for the expected number of signal events under
the SM4/FP Higgs boson hypothesis, μ is a signal strength mod-
ifier introduced to accommodate deviations from SM4/FP Higgs
boson predictions, b stands for backgrounds, and θ are nuisance
parameters describing systematic uncertainties The likelihood in
the numerator reaches its maximum, for a given μ, at θ̂μ; while
μ̂ and θ̂ define the point at which the likelihood reaches its global
maximum. The quantity μ̂ is constrained to be between 0 and μ.

The ratio of probabilities to observe a value of the test statis-
tic at least as large as the one observed in data, qobs

μ , under the
signal + background (s + b) and background-only (b) hypotheses,

CLs = P(qμ � qobs
μ | μ · s + b)

P(qμ � qobs
μ | b)

� α, (2)

is used as the criterion for excluding the signal at the 1 − α confi-
dence level.

To quantify the presence of an excess of events over what is ex-
pected for the background, we use another test statistic where the



40 CMS Collaboration / Physics Letters B 725 (2013) 36–59

Fig. 1. The observed and expected CLs values for the SM4 Higgs boson hypothe-
sis as a function of the Higgs boson mass in the range 110–600 GeV (top) and
110–145 GeV (bottom). The three horizontal lines show confidence levels of 95%,
99%, and 99.9%, defined as (1 − CLs).

likelihood appearing in the numerator is for the background-only
hypothesis:

q0 = −2 ln
L(obs | b, θ̂0)

L(obs | μ̂ · s + b, θ̂ )
. (3)

The statistical significance Z of a signal-like excess is computed
from the probability p0

p0 = P
(
q0 � qobs

0

∣∣ b
)
, (4)

henceforth referred to as the p-value, using the one-sided Gaussian
tail convention:

p0 =
+∞∫
Z

1√
2π

exp
(−x2/2

)
dx. (5)

In the Higgs boson search, we scan over Higgs boson mass hy-
potheses and look for the one giving the minimum local p-value
pmin

local, which describes the probability of a background fluctuation
for that particular Higgs boson mass hypothesis. The probability to
find a fluctuation with a local p-value lower or equal to the ob-
served pmin

local anywhere in the explored mass range is referred to
as the global p-value, pglobal.

The fact that pglobal can be significantly larger than pmin
local is of-

ten referred to as the look-elsewhere effect. The global significance
(and global p-value) of the observed excess can be evaluated in

Fig. 2. The observed and expected 95% CL upper limits on the signal strength mod-
ifier, μ = σ/σSM4 H, for the SM4 Higgs boson hypothesis as a function of the Higgs
boson mass in the range 110–600 GeV (top) and 110–145 GeV (bottom).

this case by generating pseudo-datasets, which, however, becomes
too computationally intensive and not practical for very small
p-values. Therefore, we use the method suggested in Ref. [64]. The
relationship between global and local p-values is given by:

pglobal = pmin
local + C · e−Z 2

local/2. (6)

When the look-elsewhere effect is very large, as in this search,
the constant C can be evaluated directly from data [58] by count-
ing upcrossings Nup of μ̂(mH) with the line μ = 0 and setting
C = Nup. The best-fit signal strength μ̂ in this case is obtained
from maximising the likelihood L(obs | μ̂ · s + b, θ̂ ) with no con-
straints on μ̂.

6. Results

The following conventions are used. The observed values are
shown in the plots by a solid line. A dashed line is used to indi-
cate the median of the expected results for the background-only
hypothesis. The green (dark) and yellow (light) bands show the
ranges in which the measured values are expected to reside in at
least 68% and 95% of all experiments under the background-only
hypothesis.

6.1. The SM4 results

The CLs value for the SM4 Higgs boson hypothesis as a func-
tion of its mass is shown in Fig. 1. CLs values of 0.05, 0.01, and
0.001 are indicated by horizontal thick red lines. The mass re-
gions where the observed CLs values are below these lines are



CMS Collaboration / Physics Letters B 725 (2013) 36–59 41

Fig. 3. The observed (solid lines) and expected (dashed lines) 95% CL upper limits
on the signal strength modifier, μ = σ/σSM4 H, as a function of the SM4 Higgs bo-
son mass in the range 110–600 GeV (top) and 110–145 GeV (bottom) for the four
explored Higgs boson decay modes and their combination.

excluded with the corresponding (1 − CLs) confidence levels of
95%, 99%, and 99.9%. We exclude an SM4 Higgs boson in the
range 110–600 GeV at 99% CL, and in the range 110–560 GeV
at 99.9% CL. Fig. 2 shows the 95% CL upper limits on the signal
strength modifier, μ = σ/σSM4 H, as a function of mH. The ordinate
on this plot shows the Higgs boson cross section that is excluded
at 95% CL, expressed as a multiple of the SM4 Higgs boson cross
section.

Fig. 3 shows the observed and expected limits for the three in-
dividual decay channels that have been considered, and their com-
bination. The H → ττ search is the most sensitive channel in the
mass range below 135 GeV. In the mass range 135–150 GeV, the
best sensitivity is shared between H → ZZ and H → WW. In the
mass range 150–190 GeV, the H → WW channel has the best sen-
sitivity. For masses above 190 GeV, the sensitivity is driven mostly
by the H → ZZ decay channels.

To quantify the consistency of the observed excesses with the
background-only hypothesis, we show in Fig. 4 a scan of the com-
bined local p-value p0, together with the results observed in the
individual Higgs boson decay channels. The minimum combined
local p-value pmin

local = 1.5 × 10−3 at mH � 126 GeV corresponds to
a local significance Z local of 3σ . The global probability of observing
at least as large an excess somewhere in the entire search range
110–600 GeV is estimated directly from the data using Eq. (6). The
best-fit value μ̂(mH), shown in Fig. 5, has four upcrossings with
μ̂ = 0. This can be better seen as upcrossings of the solid line
above the dashed line in Fig. 2. Taking into account the number
of observed upcrossings, the global p-value of observing a local

Fig. 4. The observed local p-value p0 as a function of the SM4 Higgs boson mass
in the range 110–600 GeV (top) and 110–145 GeV (bottom). The dashed line shows
the expected local p-values should an SM4 Higgs boson with a mass mH exist. The
expected p-value is obtained with nuisance parameters constrained by the data,
giving it some dependence on the observed data, and hence the small modulations
on top of the overall smooth trend as a function of mH.

3σ excess anywhere in the search region for the background-only
hypothesis is 0.05.

Fig. 5 also illustrates why the SM4 Higgs boson is excluded
even though a 3σ excess is observed at a mass near 126 GeV. The
band shown in Fig. 5 corresponds to the ±1 standard deviation
uncertainty (statistical + systematic) on the μ̂ value. Given these
uncertainties, the best-fit values of signal strength μ̂(mH) are sig-
nificantly smaller than expected for the SM4 Higgs boson (μ̂ = 1)
in the entire explored mass range.

Although the SM4 combination is not optimal for searching for
the SM Higgs boson, the presence of such a boson would still pro-
duce an excess in the SM4 combination. The expected significance
for a SM Higgs boson with a mass near 125 GeV is 3.5σ , which
is very close to the observed value of 3σ . For reference, the ex-
pected significance at 125 GeV with the dedicated SM Higgs boson
combination is 5.8σ [13].

6.2. The FP results

The CLs value for the FP Higgs boson hypothesis as a function of
its mass is shown in Fig. 6 (top). The CLs values of 0.05, 0.01, and
0.001 are indicated by thick red horizontal lines. The mass regions
where the observed CLs values are below these lines are excluded
with the corresponding (1−CLs) confidence levels of 95%, 99%, and
99.9%. The fermiophobic Higgs boson is excluded at 95% CL in the
mass range 110–147 GeV and at 99% CL in the range 110–133 GeV.



42 CMS Collaboration / Physics Letters B 725 (2013) 36–59

Fig. 5. The best-fit μ̂ = σ/σSM4 H as a function of the SM4 Higgs boson mass in the
range 110–600 GeV (top) and 110–145 GeV (bottom). The band corresponds to the
±1 standard deviation uncertainty on the μ̂ values.

Fig. 6 (bottom) shows the 95% CL upper limits on the signal
strength modifier, μ = σ/σFP H, as a function of mH. The ordinate
on this plot shows the Higgs boson cross section that is excluded
at 95% CL, expressed as a multiple of the FP Higgs boson cross
section.

Fig. 7 (top) shows the local p-value as a function of the FP
Higgs boson mass for each run period and for their combination.
The largest upwards fluctuation of events over the expected back-
ground is observed at 125.5 GeV, and is computed to have a local
significance of 3.2σ . This deviation from the expected limit is too
weak to be consistent with the fermiophobic Higgs boson signal,
as can be seen in Fig. 7 (bottom), which shows that the observed
signal strength for a fermiophobic Higgs boson at 125.5 GeV is
0.49 ± 0.18, as obtained from the fit of signal + background on
data. The excess of events at 125.5 GeV is present in the SM Higgs
boson search reported in Ref. [13] and corresponds to the discov-
ery of the new boson around 125 GeV. This recently observed
boson is not consistent with a fermiophobic Higgs boson at 99%
confidence level.

As in the SM4 case, the FP analysis is not optimal for searching
for the SM Higgs boson, but still has some sensitivity. The expected
sensitivity to a SM Higgs boson with a mass of 125 GeV is 1.3σ ;
we observe 3.2σ . For reference, in the dedicated SM Higgs boson
diphoton analysis, using the same dataset as the FP combination
here, the observed significance of the excess near 125 GeV is 4.1σ ,
with an expected sensitivity of 2.8σ [13]. In both the SM and FP
diphoton analyses the observed significances for the SM Higgs bo-
son are greater than the expected, but statistically compatible at
the O(10%) level.

Fig. 6. (Top) The observed and expected CLs values for the FP Higgs boson hypoth-
esis as a function of the Higgs boson mass in the range 110–150 GeV. (Bottom)
The observed and expected 95% CL upper limits on the signal strength modifier,
μ = σ/σFP H, as a function of the FP Higgs boson mass in the range 110–150 GeV.

7. Summary

Searches are reported for Higgs bosons in the context of ei-
ther the standard model extended to include a fourth generation
of fermions with masses of up to 600 GeV or fermiophobic models.
For the former, results from three decay modes (ττ , WW, and ZZ)
are combined, whilst for the latter the diphoton decay is exploited.
The analysed proton–proton collision data correspond to integrated
luminosities of up to 5.1 fb−1 at 7 TeV and up to 5.3 fb−1 at 8 TeV.
The observed results exclude the SM4 Higgs boson in the mass
range 110–600 GeV at 99% CL, and in the mass range 110–560 GeV
at 99.9% CL. A fermiophobic Higgs boson is excluded in the mass
range 110–147 GeV at 95% CL, and in the range 110–133 GeV at
99% CL. The recently observed boson with a mass near 125 GeV is
not consistent with either an SM4 or a fermiophobic Higgs boson.

Acknowledgements

We congratulate our colleagues in the CERN accelerator depart-
ments for the excellent performance of the LHC and thank the
technical and administrative staffs at CERN and at other CMS in-
stitutes for their contributions to the success of the CMS effort.
In addition, we gratefully acknowledge the computing centres and
personnel of the Worldwide LHC Computing Grid for delivering so
effectively the computing infrastructure essential to our analyses.
Finally, we acknowledge the enduring support for the construction
and operation of the LHC and the CMS detector provided by the
following funding agencies: BMWF and FWF (Austria); FNRS and
FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS
(Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS
(Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09
and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland);



CMS Collaboration / Physics Letters B 725 (2013) 36–59 43

Fig. 7. (Top) The observed local p-value p0 as a function of the FP Higgs boson
mass in the range 110–150 GeV. The dashed–dotted line shows the expected local
p-values should a fermiophobic Higgs boson with a mass mH exist. The contribu-
tions to the expected limit for each run period are shown. (Bottom) The best-fit
μ̂ = σ/σFP H as a function of the FP Higgs boson mass in the range 110–150 GeV.
The band corresponds to the ±1 standard deviation uncertainty on the μ̂ values.

CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany);
GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (In-
dia); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Re-
public of Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and
UASLP-FAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE
and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Geor-
gia, Ukraine, Uzbekistan); MON, RosAtom, RAS and RFBR (Russia);
MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies
(Switzerland); NSC (Taipei); ThEPCenter, IPST and NSTDA (Thai-
land); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United
Kingdom); DOE and NSF (USA). Individuals have received sup-
port from the Marie-Curie programme and the European Research
Council (European Union); the Leventis Foundation; the A.P. Sloan
Foundation; the Alexander von Humboldt Foundation; the Belgian
Federal Science Policy Office; the Fonds pour la Formation à la
Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the
Agentschap voor Innovatie door Wetenschap en Technologie (IWT-
Belgium); the Ministry of Education, Youth and Sports (MEYS) of
Czech Republic; the Council of Science and Industrial Research, In-
dia; the Compagnia di San Paolo (Torino); and the HOMING PLUS
programme of Foundation for Polish Science, cofinanced from Eu-
ropean Union, Regional Development Fund.

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Institut für Hochenergiephysik der OeAW, Wien, Austria

V. Mossolov, N. Shumeiko, J. Suarez Gonzalez

National Centre for Particle and High Energy Physics, Minsk, Belarus

S. Bansal, T. Cornelis, E.A. De Wolf, X. Janssen, S. Luyckx, L. Mucibello, S. Ochesanu,
B. Roland, R. Rougny, M. Selvaggi, Z. Staykova, H. Van Haevermaet, P. Van Mechelen,
N. Van Remortel, A. Van Spilbeeck

Universiteit Antwerpen, Antwerpen, Belgium

F. Blekman, S. Blyweert, J. D’Hondt, R. Gonzalez Suarez, A. Kalogeropoulos, M. Maes,
A. Olbrechts, W. Van Doninck, P. Van Mulders, G.P. Van Onsem, I. Villella

Vrije Universiteit Brussel, Brussel, Belgium

B. Clerbaux, G. De Lentdecker, V. Dero, A.P.R. Gay, T. Hreus, A. Léonard, P.E. Marage,
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Université Libre de Bruxelles, Bruxelles, Belgium

V. Adler, K. Beernaert, A. Cimmino, S. Costantini, G. Garcia, M. Grunewald, B. Klein,
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Ghent University, Ghent, Belgium

S. Basegmez, G. Bruno, R. Castello, L. Ceard, C. Delaere, T. du Pree, D. Favart,
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Université Catholique de Louvain, Louvain-la-Neuve, Belgium

N. Beliy, T. Caebergs, E. Daubie, G.H. Hammad

Université de Mons, Mons, Belgium

G.A. Alves, M. Correa Martins Junior, D. De Jesus Damiao, T. Martins, M.E. Pol,
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Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil

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Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil

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a Universidade Estadual Paulista, São Paulo, Brazil
b Universidade Federal do ABC, São Paulo, Brazil

V. Genchev 4, P. Iaydjiev 4, S. Piperov, M. Rodozov, S. Stoykova, G. Sultanov, V. Tcholakov,
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Institute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria



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University of Sofia, Sofia, Bulgaria

J.G. Bian, G.M. Chen, H.S. Chen, C.H. Jiang, D. Liang, S. Liang, X. Meng, J. Tao, J. Wang,
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Institute of High Energy Physics, Beijing, China

C. Asawatangtrakuldee, Y. Ban, S. Guo, Y. Guo, Q. Li, W. Li, S. Liu, Y. Mao, S.J. Qian,
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State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China

C. Avila, J.P. Gomez, B. Gomez Moreno, A.F. Osorio Oliveros, J.C. Sanabria

Universidad de Los Andes, Bogota, Colombia

N. Godinovic, D. Lelas, R. Plestina 5, D. Polic, I. Puljak 4

Technical University of Split, Split, Croatia

Z. Antunovic, M. Kovac

University of Split, Split, Croatia

V. Brigljevic, S. Duric, K. Kadija, J. Luetic, S. Morovic

Institute Rudjer Boskovic, Zagreb, Croatia

A. Attikis, M. Galanti, G. Mavromanolakis, J. Mousa, C. Nicolaou, F. Ptochos, P.A. Razis

University of Cyprus, Nicosia, Cyprus

M. Finger, M. Finger Jr.

Charles University, Prague, Czech Republic

Y. Assran 6, S. Elgammal 7, A. Ellithi Kamel 8, M.A. Mahmoud 9, A. Radi 10,11

Academy of Scientific Research and Technology of the Arab Republic of Egypt, Egyptian Network of High Energy Physics, Cairo, Egypt

M. Kadastik, M. Müntel, M. Raidal, L. Rebane, A. Tiko

National Institute of Chemical Physics and Biophysics, Tallinn, Estonia

P. Eerola, G. Fedi, M. Voutilainen

Department of Physics, University of Helsinki, Helsinki, Finland

J. Härkönen, A. Heikkinen, V. Karimäki, R. Kinnunen, M.J. Kortelainen, T. Lampén,
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Helsinki Institute of Physics, Helsinki, Finland

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Lappeenranta University of Technology, Lappeenranta, Finland

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DSM/IRFU, CEA/Saclay, Gif-sur-Yvette, France



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Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3–CNRS, Palaiseau, France

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Institut Pluridisciplinaire Hubert Curien, Université de Strasbourg, Université de Haute Alsace Mulhouse, CNRS/IN2P3, Strasbourg, France

F. Fassi, D. Mercier

Centre de Calcul de l’Institut National de Physique Nucleaire et de Physique des Particules, CNRS/IN2P3, Villeurbanne, France

S. Beauceron, N. Beaupere, O. Bondu, G. Boudoul, J. Chasserat, R. Chierici 4, D. Contardo,
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L. Mirabito, S. Perries, V. Sordini, Y. Tschudi, P. Verdier, S. Viret

Université de Lyon, Université Claude Bernard Lyon 1, CNRS–IN2P3, Institut de Physique Nucléaire de Lyon, Villeurbanne, France

Z. Tsamalaidze 14

Institute of High Energy Physics and Informatization, Tbilisi State University, Tbilisi, Georgia

G. Anagnostou, S. Beranek, M. Edelhoff, L. Feld, N. Heracleous, O. Hindrichs, R. Jussen,
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RWTH Aachen University, I. Physikalisches Institut, Aachen, Germany

M. Ata, J. Caudron, E. Dietz-Laursonn, D. Duchardt, M. Erdmann, R. Fischer, A. Güth,
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RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany

M. Bontenackels, V. Cherepanov, G. Flügge, H. Geenen, M. Geisler, W. Haj Ahmad,
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RWTH Aachen University, III. Physikalisches Institut B, Aachen, Germany

M. Aldaya Martin, J. Behr, W. Behrenhoff, U. Behrens, M. Bergholz 16, A. Bethani, K. Borras,
A. Burgmeier, A. Cakir, L. Calligaris, A. Campbell, E. Castro, F. Costanza, D. Dammann,
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Deutsches Elektronen-Synchrotron, Hamburg, Germany

C. Autermann, V. Blobel, J. Draeger, H. Enderle, J. Erfle, U. Gebbert, M. Görner,
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E. Schlieckau, A. Schmidt, M. Schröder, T. Schum, M. Seidel, V. Sola, H. Stadie,
G. Steinbrück, J. Thomsen, L. Vanelderen

University of Hamburg, Hamburg, Germany

C. Barth, J. Berger, C. Böser, T. Chwalek, W. De Boer, A. Descroix, A. Dierlamm, M. Feindt,
M. Guthoff 4, C. Hackstein, F. Hartmann, T. Hauth 4, M. Heinrich, H. Held, K.H. Hoffmann,
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N. Ratnikova, S. Röcker, A. Scheurer, F.-P. Schilling, G. Schott, H.J. Simonis, F.M. Stober,
D. Troendle, R. Ulrich, J. Wagner-Kuhr, S. Wayand, T. Weiler, M. Zeise

Institut für Experimentelle Kernphysik, Karlsruhe, Germany

G. Daskalakis, T. Geralis, S. Kesisoglou, A. Kyriakis, D. Loukas, I. Manolakos, A. Markou,
C. Markou, C. Mavrommatis, E. Ntomari

Institute of Nuclear Physics “Demokritos”, Aghia Paraskevi, Greece

L. Gouskos, T.J. Mertzimekis, A. Panagiotou, N. Saoulidou

University of Athens, Athens, Greece

I. Evangelou, C. Foudas 4, P. Kokkas, N. Manthos, I. Papadopoulos, V. Patras

University of Ioánnina, Ioánnina, Greece

G. Bencze, C. Hajdu 4, P. Hidas, D. Horvath 17, F. Sikler, V. Veszpremi, G. Vesztergombi 18

KFKI Research Institute for Particle and Nuclear Physics, Budapest, Hungary

N. Beni, S. Czellar, J. Molnar, J. Palinkas, Z. Szillasi

Institute of Nuclear Research ATOMKI, Debrecen, Hungary

J. Karancsi, P. Raics, Z.L. Trocsanyi, B. Ujvari

University of Debrecen, Debrecen, Hungary

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Panjab University, Chandigarh, India

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University of Delhi, Delhi, India

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Saha Institute of Nuclear Physics, Kolkata, India

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Bhabha Atomic Research Centre, Mumbai, India

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Tata Institute of Fundamental Research – EHEP, Mumbai, India



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Tata Institute of Fundamental Research – HECR, Mumbai, India

H. Arfaei, H. Bakhshiansohi 21, S.M. Etesami 22, A. Fahim 21, M. Hashemi, H. Hesari,
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B. Safarzadeh 23, M. Zeinali 22

Institute for Research in Fundamental Sciences (IPM), Tehran, Iran

M. Abbrescia a,b, L. Barbone a,b, C. Calabria a,b,4, S.S. Chhibra a,b, A. Colaleo a, D. Creanza a,c,
N. De Filippis a,c,4, M. De Palma a,b, L. Fiore a, G. Iaselli a,c, L. Lusito a,b, G. Maggi a,c,
M. Maggi a, B. Marangelli a,b, S. My a,c, S. Nuzzo a,b, N. Pacifico a,b, A. Pompili a,b,
G. Pugliese a,c, G. Selvaggi a,b, L. Silvestris a, G. Singh a,b, R. Venditti a,b, G. Zito a

a INFN Sezione di Bari, Bari, Italy
b Università di Bari, Bari, Italy
c Politecnico di Bari, Bari, Italy

G. Abbiendi a, A.C. Benvenuti a, D. Bonacorsi a,b, S. Braibant-Giacomelli a,b, L. Brigliadori a,b,
P. Capiluppi a,b, A. Castro a,b, F.R. Cavallo a, M. Cuffiani a,b, G.M. Dallavalle a, F. Fabbri a,
A. Fanfani a,b, D. Fasanella a,b,4, P. Giacomelli a, C. Grandi a, L. Guiducci a,b, S. Marcellini a,
G. Masetti a, M. Meneghelli a,b,4, A. Montanari a, F.L. Navarria a,b, F. Odorici a, A. Perrotta a,
F. Primavera a,b, A.M. Rossi a,b, T. Rovelli a,b, G.P. Siroli a,b, R. Travaglini a,b

a INFN Sezione di Bologna, Bologna, Italy
b Università di Bologna, Bologna, Italy

S. Albergo a,b, G. Cappello a,b, M. Chiorboli a,b, S. Costa a,b, R. Potenza a,b, A. Tricomi a,b,
C. Tuve a,b

a INFN Sezione di Catania, Catania, Italy
b Università di Catania, Catania, Italy

G. Barbagli a, V. Ciulli a,b, C. Civinini a, R. D’Alessandro a,b, E. Focardi a,b, S. Frosali a,b,
E. Gallo a, S. Gonzi a,b, M. Meschini a, S. Paoletti a, G. Sguazzoni a, A. Tropiano a,4

a INFN Sezione di Firenze, Firenze, Italy
b Università di Firenze, Firenze, Italy

L. Benussi, S. Bianco, S. Colafranceschi 24, F. Fabbri, D. Piccolo

INFN Laboratori Nazionali di Frascati, Frascati, Italy

P. Fabbricatore a, R. Musenich a, S. Tosi a,b

a INFN Sezione di Genova, Genova, Italy
b Università di Genova, Genova, Italy

A. Benaglia a,b,4, F. De Guio a,b, L. Di Matteo a,b,4, S. Fiorendi a,b, S. Gennai a,4, A. Ghezzi a,b,
S. Malvezzi a, R.A. Manzoni a,b, A. Martelli a,b, A. Massironi a,b,4, D. Menasce a, L. Moroni a,
M. Paganoni a,b, D. Pedrini a, S. Ragazzi a,b, N. Redaelli a, S. Sala a, T. Tabarelli de Fatis a,b

a INFN Sezione di Milano-Bicocca, Milano, Italy
b Università di Milano-Bicocca, Milano, Italy

S. Buontempo a, C.A. Carrillo Montoya a,4, N. Cavallo a,c, A. De Cosa a,b,4, O. Dogangun a,b,
F. Fabozzi a,c, A.O.M. Iorio a,b, L. Lista a, S. Meola a,d,25, M. Merola a, P. Paolucci a,4

a INFN Sezione di Napoli, Napoli, Italy
b Università di Napoli ‘Federico II’, Napoli, Italy
c Università della Basilicata (Potenza), Napoli, Italy
d Università G. Marconi (Roma), Napoli, Italy



50 CMS Collaboration / Physics Letters B 725 (2013) 36–59

P. Azzi a, N. Bacchetta a,4, D. Bisello a,b, A. Branca a,b,4, R. Carlin a,b, P. Checchia a,
T. Dorigo a, F. Gasparini a,b, U. Gasparini a,b, A. Gozzelino a, K. Kanishchev a,c, S. Lacaprara a,
I. Lazzizzera a,c, M. Margoni a,b, A.T. Meneguzzo a,b, J. Pazzini a,b, M. Pegoraro a,
N. Pozzobon a,b, P. Ronchese a,b, F. Simonetto a,b, E. Torassa a, M. Tosi a,b,4, S. Vanini a,b,
P. Zotto a,b, G. Zumerle a,b

a INFN Sezione di Padova, Padova, Italy
b Università di Padova, Padova, Italy
c Università di Trento (Trento), Padova, Italy

M. Gabusi a,b, S.P. Ratti a,b, C. Riccardi a,b, P. Torre a,b, P. Vitulo a,b

a INFN Sezione di Pavia, Pavia, Italy
b Università di Pavia, Pavia, Italy

M. Biasini a,b, G.M. Bilei a, L. Fanò a,b, P. Lariccia a,b, A. Lucaroni a,b,4, G. Mantovani a,b,
M. Menichelli a, A. Nappi a,b, F. Romeo a,b, A. Saha a, A. Santocchia a,b, A. Spiezia a,b,
S. Taroni a,b,4

a INFN Sezione di Perugia, Perugia, Italy
b Università di Perugia, Perugia, Italy

P. Azzurri a,c, G. Bagliesi a, J. Bernardini a, T. Boccali a, G. Broccolo a,c, R. Castaldi a,
R.T. D’Agnolo a,c, R. Dell’Orso a, F. Fiori a,b,4, L. Foà a,c, A. Giassi a, A. Kraan a, F. Ligabue a,c,
T. Lomtadze a, L. Martini a,26, A. Messineo a,b, F. Palla a, A. Rizzi a,b, A.T. Serban a,27,
P. Spagnolo a, P. Squillacioti a,4, R. Tenchini a, G. Tonelli a,b,4, A. Venturi a,4, P.G. Verdini a

a INFN Sezione di Pisa, Pisa, Italy
b Università di Pisa, Pisa, Italy
c Scuola Normale Superiore di Pisa, Pisa, Italy

L. Barone a,b, F. Cavallari a, D. Del Re a,b,4, M. Diemoz a, M. Grassi a,b,4, E. Longo a,b,
P. Meridiani a,4, F. Micheli a,b, S. Nourbakhsh a,b, G. Organtini a,b, R. Paramatti a,
S. Rahatlou a,b, M. Sigamani a, L. Soffi a,b

a INFN Sezione di Roma, Roma, Italy
b Università di Roma, Roma, Italy

N. Amapane a,b, R. Arcidiacono a,c, S. Argiro a,b, M. Arneodo a,c, C. Biino a, N. Cartiglia a,
M. Costa a,b, G. Dellacasa a, N. Demaria a, C. Mariotti a,4, S. Maselli a, E. Migliore a,b,
V. Monaco a,b, M. Musich a,4, M.M. Obertino a,c, N. Pastrone a, M. Pelliccioni a,
A. Potenza a,b, A. Romero a,b, R. Sacchi a,b, A. Solano a,b, A. Staiano a, A. Vilela Pereira a

a INFN Sezione di Torino, Torino, Italy
b Università di Torino, Torino, Italy
c Università del Piemonte Orientale (Novara), Torino, Italy

S. Belforte a, V. Candelise a,b, F. Cossutti a, G. Della Ricca a,b, B. Gobbo a, M. Marone a,b,4,
D. Montanino a,b,4, A. Penzo a, A. Schizzi a,b

a INFN Sezione di Trieste, Trieste, Italy
b Università di Trieste, Trieste, Italy

S.G. Heo, T.Y. Kim, S.K. Nam

Kangwon National University, Chunchon, Republic of Korea

S. Chang, D.H. Kim, G.N. Kim, D.J. Kong, H. Park, S.R. Ro, D.C. Son, T. Son

Kyungpook National University, Daegu, Republic of Korea

J.Y. Kim, Zero J. Kim, S. Song

Chonnam National University, Institute for Universe and Elementary Particles, Kwangju, Republic of Korea



CMS Collaboration / Physics Letters B 725 (2013) 36–59 51

S. Choi, D. Gyun, B. Hong, M. Jo, H. Kim, T.J. Kim, K.S. Lee, D.H. Moon, S.K. Park

Korea University, Seoul, Republic of Korea

M. Choi, J.H. Kim, C. Park, I.C. Park, S. Park, G. Ryu

University of Seoul, Seoul, Republic of Korea

Y. Cho, Y. Choi, Y.K. Choi, J. Goh, M.S. Kim, E. Kwon, B. Lee, J. Lee, S. Lee, H. Seo, I. Yu

Sungkyunkwan University, Suwon, Republic of Korea

M.J. Bilinskas, I. Grigelionis, M. Janulis, A. Juodagalvis

Vilnius University, Vilnius, Lithuania

H. Castilla-Valdez, E. De La Cruz-Burelo, I. Heredia-de La Cruz, R. Lopez-Fernandez,
R. Magaña Villalba, J. Martínez-Ortega, A. Sanchez-Hernandez, L.M. Villasenor-Cendejas

Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico

S. Carrillo Moreno, F. Vazquez Valencia

Universidad Iberoamericana, Mexico City, Mexico

H.A. Salazar Ibarguen

Benemerita Universidad Autonoma de Puebla, Puebla, Mexico

E. Casimiro Linares, A. Morelos Pineda, M.A. Reyes-Santos

Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico

D. Krofcheck

University of Auckland, Auckland, New Zealand

A.J. Bell, P.H. Butler, R. Doesburg, S. Reucroft, H. Silverwood

University of Canterbury, Christchurch, New Zealand

M. Ahmad, M.I. Asghar, H.R. Hoorani, S. Khalid, W.A. Khan, T. Khurshid, S. Qazi, M.A. Shah,
M. Shoaib

National Centre for Physics, Quaid-I-Azam University, Islamabad, Pakistan

H. Bialkowska, B. Boimska, T. Frueboes, R. Gokieli, M. Górski, M. Kazana, K. Nawrocki,
K. Romanowska-Rybinska, M. Szleper, G. Wrochna, P. Zalewski

National Centre for Nuclear Research, Swierk, Poland

G. Brona, K. Bunkowski, M. Cwiok, W. Dominik, K. Doroba, A. Kalinowski, M. Konecki,
J. Krolikowski

Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland

N. Almeida, P. Bargassa, A. David, P. Faccioli, P.G. Ferreira Parracho, M. Gallinaro, J. Seixas,
J. Varela, P. Vischia

Laboratório de Instrumentação e Física Experimental de Partículas, Lisboa, Portugal

P. Bunin, I. Golutvin, I. Gorbunov, A. Kamenev, V. Karjavin, V. Konoplyanikov, G. Kozlov,
A. Lanev, A. Malakhov, P. Moisenz, V. Palichik, V. Perelygin, M. Savina, S. Shmatov,
V. Smirnov, A. Volodko, A. Zarubin

Joint Institute for Nuclear Research, Dubna, Russia



52 CMS Collaboration / Physics Letters B 725 (2013) 36–59

S. Evstyukhin, V. Golovtsov, Y. Ivanov, V. Kim, P. Levchenko, V. Murzin, V. Oreshkin,
I. Smirnov, V. Sulimov, L. Uvarov, S. Vavilov, A. Vorobyev, An. Vorobyev

Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg), Russia

Yu. Andreev, A. Dermenev, S. Gninenko, N. Golubev, M. Kirsanov, N. Krasnikov,
V. Matveev, A. Pashenkov, D. Tlisov, A. Toropin

Institute for Nuclear Research, Moscow, Russia

V. Epshteyn, M. Erofeeva, V. Gavrilov, M. Kossov 4, N. Lychkovskaya, V. Popov, G. Safronov,
S. Semenov, V. Stolin, E. Vlasov, A. Zhokin

Institute for Theoretical and Experimental Physics, Moscow, Russia

V. Andreev, M. Azarkin, I. Dremin, M. Kirakosyan, A. Leonidov, G. Mesyats, S.V. Rusakov,
A. Vinogradov

P.N. Lebedev Physical Institute, Moscow, Russia

A. Belyaev, E. Boos, M. Dubinin 3, L. Dudko, A. Ershov, A. Gribushin, V. Klyukhin,
O. Kodolova, I. Lokhtin, A. Markina, S. Obraztsov, M. Perfilov, S. Petrushanko, A. Popov,
L. Sarycheva †, V. Savrin, A. Snigirev

Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia

I. Azhgirey, I. Bayshev, S. Bitioukov, V. Grishin 4, V. Kachanov, D. Konstantinov,
A. Korablev, V. Krychkine, V. Petrov, R. Ryutin, A. Sobol, L. Tourtchanovitch, S. Troshin,
N. Tyurin, A. Uzunian, A. Volkov

State Research Center of Russian Federation, Institute for High Energy Physics, Protvino, Russia

P. Adzic 28, M. Djordjevic, M. Ekmedzic, D. Krpic 28, J. Milosevic

University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade, Serbia

M. Aguilar-Benitez, J. Alcaraz Maestre, P. Arce, C. Battilana, E. Calvo, M. Cerrada,
M. Chamizo Llatas, N. Colino, B. De La Cruz, A. Delgado Peris, D. Domínguez Vázquez,
C. Fernandez Bedoya, J.P. Fernández Ramos, A. Ferrando, J. Flix, M.C. Fouz, P. Garcia-Abia,
O. Gonzalez Lopez, S. Goy Lopez, J.M. Hernandez, M.I. Josa, G. Merino, J. Puerta Pelayo,
A. Quintario Olmeda, I. Redondo, L. Romero, J. Santaolalla, M.S. Soares, C. Willmott

Centro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain

C. Albajar, G. Codispoti, J.F. de Trocóniz

Universidad Autónoma de Madrid, Madrid, Spain

H. Brun, J. Cuevas, J. Fernandez Menendez, S. Folgueras, I. Gonzalez Caballero,
L. Lloret Iglesias, J. Piedra Gomez

Universidad de Oviedo, Oviedo, Spain

J.A. Brochero Cifuentes, I.J. Cabrillo, A. Calderon, S.H. Chuang, J. Duarte Campderros,
M. Felcini 29, M. Fernandez, G. Gomez, J. Gonzalez Sanchez, A. Graziano, C. Jorda,
A. Lopez Virto, J. Marco, R. Marco, C. Martinez Rivero, F. Matorras, F.J. Munoz Sanchez,
T. Rodrigo, A.Y. Rodríguez-Marrero, A. Ruiz-Jimeno, L. Scodellaro, M. Sobron Sanudo,
I. Vila, R. Vilar Cortabitarte

Instituto de Física de Cantabria (IFCA), CSIC, Universidad de Cantabria, Santander, Spain



CMS Collaboration / Physics Letters B 725 (2013) 36–59 53

D. Abbaneo, E. Auffray, G. Auzinger, P. Baillon, A.H. Ball, D. Barney, J.F. Benitez, C. Bernet 5,
G. Bianchi, P. Bloch, A. Bocci, A. Bonato, C. Botta, H. Breuker, T. Camporesi, G. Cerminara,
T. Christiansen, J.A. Coarasa Perez, D. D’Enterria, A. Dabrowski, A. De Roeck, S. Di Guida,
M. Dobson, N. Dupont-Sagorin, A. Elliott-Peisert, B. Frisch, W. Funk, G. Georgiou,
M. Giffels, D. Gigi, K. Gill, D. Giordano, M. Giunta, F. Glege, R. Gomez-Reino Garrido,
P. Govoni, S. Gowdy, R. Guida, M. Hansen, P. Harris, C. Hartl, J. Harvey, B. Hegner,
A. Hinzmann, V. Innocente, P. Janot, K. Kaadze, E. Karavakis, K. Kousouris, P. Lecoq,
Y.-J. Lee, P. Lenzi, C. Lourenço, T. Mäki, M. Malberti, L. Malgeri, M. Mannelli, L. Masetti,
F. Meijers, S. Mersi, E. Meschi, R. Moser, M.U. Mozer, M. Mulders, P. Musella, E. Nesvold,
T. Orimoto, L. Orsini, E. Palencia Cortezon, E. Perez, L. Perrozzi, A. Petrilli, A. Pfeiffer,
M. Pierini, M. Pimiä, D. Piparo, G. Polese, L. Quertenmont, A. Racz, W. Reece,
J. Rodrigues Antunes, G. Rolandi 30, T. Rommerskirchen, C. Rovelli 31, M. Rovere,
H. Sakulin, F. Santanastasio, C. Schäfer, C. Schwick, I. Segoni, S. Sekmen, A. Sharma,
P. Siegrist, P. Silva, M. Simon, P. Sphicas 32, D. Spiga, A. Tsirou, G.I. Veres 18, J.R. Vlimant,
H.K. Wöhri, S.D. Worm 33, W.D. Zeuner

CERN, European Organization for Nuclear Research, Geneva, Switzerland

W. Bertl, K. Deiters, W. Erdmann, K. Gabathuler, R. Horisberger, Q. Ingram, H.C. Kaestli,
S. König, D. Kotlinski, U. Langenegger, F. Meier, D. Renker, T. Rohe, J. Sibille 34

Paul Scherrer Institut, Villigen, Switzerland

L. Bäni, P. Bortignon, M.A. Buchmann, B. Casal, N. Chanon, A. Deisher, G. Dissertori,
M. Dittmar, M. Dünser, J. Eugster, K. Freudenreich, C. Grab, D. Hits, P. Lecomte,
W. Lustermann, A.C. Marini, P. Martinez Ruiz del Arbol, N. Mohr, F. Moortgat, C. Nägeli 35,
P. Nef, F. Nessi-Tedaldi, F. Pandolfi, L. Pape, F. Pauss, M. Peruzzi, F.J. Ronga, M. Rossini,
L. Sala, A.K. Sanchez, A. Starodumov 36, B. Stieger, M. Takahashi, L. Tauscher †, A. Thea,
K. Theofilatos, D. Treille, C. Urscheler, R. Wallny, H.A. Weber, L. Wehrli

Institute for Particle Physics, ETH Zurich, Zurich, Switzerland

C. Amsler, V. Chiochia, S. De Visscher, C. Favaro, M. Ivova Rikova, B. Millan Mejias,
P. Otiougova, P. Robmann, H. Snoek, S. Tupputi, M. Verzetti

Universität Zürich, Zurich, Switzerland

Y.H. Chang, K.H. Chen, C.M. Kuo, S.W. Li, W. Lin, Z.K. Liu, Y.J. Lu, D. Mekterovic, A.P. Singh,
R. Volpe, S.S. Yu

National Central University, Chung-Li, Taiwan

P. Bartalini, P. Chang, Y.H. Chang, Y.W. Chang, Y. Chao, K.F. Chen, C. Dietz, U. Grundler,
W.-S. Hou, Y. Hsiung, K.Y. Kao, Y.J. Lei, R.-S. Lu, D. Majumder, E. Petrakou, X. Shi, J.G. Shiu,
Y.M. Tzeng, X. Wan, M. Wang

National Taiwan University (NTU), Taipei, Taiwan

A. Adiguzel, M.N. Bakirci 37, S. Cerci 38, C. Dozen, I. Dumanoglu, E. Eskut, S. Girgis,
G. Gokbulut, E. Gurpinar, I. Hos, E.E. Kangal, T. Karaman, G. Karapinar 39, A. Kayis Topaksu,
G. Onengut, K. Ozdemir, S. Ozturk 40, A. Polatoz, K. Sogut 41, D. Sunar Cerci 38, B. Tali 38,
H. Topakli 37, L.N. Vergili, M. Vergili

Cukurova University, Adana, Turkey

I.V. Akin, T. Aliev, B. Bilin, S. Bilmis, M. Deniz, H. Gamsizkan, A.M. Guler, K. Ocalan,
A. Ozpineci, M. Serin, R. Sever, U.E. Surat, M. Yalvac, E. Yildirim, M. Zeyrek

Middle East Technical University, Physics Department, Ankara, Turkey



54 CMS Collaboration / Physics Letters B 725 (2013) 36–59

E. Gülmez, B. Isildak 42, M. Kaya 43, O. Kaya 43, S. Ozkorucuklu 44, N. Sonmez 45

Bogazici University, Istanbul, Turkey

K. Cankocak

Istanbul Technical University, Istanbul, Turkey

L. Levchuk

National Scientific Center, Kharkov Institute of Physics and Technology, Kharkov, Ukraine

F. Bostock, J.J. Brooke, E. Clement, D. Cussans, H. Flacher, R. Frazier, J. Goldstein,
M. Grimes, G.P. Heath, H.F. Heath, L. Kreczko, S. Metson, D.M. Newbold 33, K. Nirunpong,
A. Poll, S. Senkin, V.J. Smith, T. Williams

University of Bristol, Bristol, United Kingdom

L. Basso 46, K.W. Bell, A. Belyaev 46, C. Brew, R.M. Brown, D.J.A. Cockerill, J.A. Coughlan,
K. Harder, S. Harper, J. Jackson, B.W. Kennedy, E. Olaiya, D. Petyt, B.C. Radburn-Smith,
C.H. Shepherd-Themistocleous, I.R. Tomalin, W.J. Womersley

Rutherford Appleton Laboratory, Didcot, United Kingdom

R. Bainbridge, G. Ball, R. Beuselinck, O. Buchmuller, D. Colling, N. Cripps, M. Cutajar,
P. Dauncey, G. Davies, M. Della Negra, W. Ferguson, J. Fulcher, D. Futyan, A. Gilbert,
A. Guneratne Bryer, G. Hall, Z. Hatherell, J. Hays, G. Iles, M. Jarvis, G. Karapostoli, L. Lyons,
A.-M. Magnan, J. Marrouche, B. Mathias, R. Nandi, J. Nash, A. Nikitenko 36,
A. Papageorgiou, J. Pela 4, M. Pesaresi, K. Petridis, M. Pioppi 47, D.M. Raymond,
S. Rogerson, A. Rose, M.J. Ryan, C. Seez, P. Sharp †, A. Sparrow, M. Stoye, A. Tapper,
M. Vazquez Acosta, T. Virdee, S. Wakefield, N. Wardle, T. Whyntie

Imperial College, London, United Kingdom

M. Chadwick, J.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, D. Leggat, D. Leslie, W. Martin,
I.D. Reid, P. Symonds, L. Teodorescu, M. Turner

Brunel University, Uxbridge, United Kingdom

K. Hatakeyama, H. Liu, T. Scarborough

Baylor University, Waco, USA

O. Charaf, C. Henderson, P. Rumerio

The University of Alabama, Tuscaloosa, USA

A. Avetisyan, T. Bose, C. Fantasia, A. Heister, P. Lawson, D. Lazic, J. Rohlf, D. Sperka,
J. St. John, L. Sulak

Boston University, Boston, USA

J. Alimena, S. Bhattacharya, D. Cutts, A. Ferapontov, U. Heintz, S. Jabeen, G. Kukartsev,
E. Laird, G. Landsberg, M. Luk, M. Narain, D. Nguyen, M. Segala, T. Sinthuprasith, T. Speer,
K.V. Tsang

Brown University, Providence, USA

R. Breedon, G. Breto, M. Calderon De La Barca Sanchez, S. Chauhan, M. Chertok, J. Conway,
R. Conway, P.T. Cox, J. Dolen, R. Erbacher, M. Gardner, R. Houtz, W. Ko, A. Kopecky,
R. Lander, T. Miceli, D. Pellett, F. Ricci-Tam, B. Rutherford, M. Searle, J. Smith, M. Squires,



CMS Collaboration / Physics Letters B 725 (2013) 36–59 55

M. Tripathi, R. Vasquez Sierra

University of California, Davis, Davis, USA

V. Andreev, D. Cline, R. Cousins, J. Duris, S. Erhan, P. Everaerts, C. Farrell, J. Hauser,
M. Ignatenko, C. Jarvis, C. Plager, G. Rakness, P. Schlein †, V. Valuev, M. Weber

University of California, Los Angeles, USA

J. Babb, R. Clare, M.E. Dinardo, J. Ellison, J.W. Gary, F. Giordano, G. Hanson, G.Y. Jeng 48,
H. Liu, O.R. Long, A. Luthra, H. Nguyen, S. Paramesvaran, J. Sturdy, S. Sumowidagdo,
R. Wilken, S. Wimpenny

University of California, Riverside, Riverside, USA

W. Andrews, J.G. Branson, G.B. Cerati, S. Cittolin, D. Evans, F. Golf, A. Holzner, R. Kelley,
M. Lebourgeois, J. Letts, I. Macneill, B. Mangano, S. Padhi, C. Palmer, G. Petrucciani,
M. Pieri, M. Sani, V. Sharma, S. Simon, E. Sudano, M. Tadel, Y. Tu, A. Vartak,
S. Wasserbaech 49, F. Würthwein, A. Yagil, J. Yoo

University of California, San Diego, La Jolla, USA

D. Barge, R. Bellan, C. Campagnari, M. D’Alfonso, T. Danielson, K. Flowers, P. Geffert,
J. Incandela, C. Justus, P. Kalavase, S.A. Koay, D. Kovalskyi, V. Krutelyov, S. Lowette,
N. Mccoll, V. Pavlunin, F. Rebassoo, J. Ribnik, J. Richman, R. Rossin, D. Stuart, W. To,
C. West

University of California, Santa Barbara, Santa Barbara, USA

A. Apresyan, A. Bornheim, J. Bunn, Y. Chen, E. Di Marco, J. Duarte, M. Gataullin, D. Kcira,
Y. Ma, A. Mott, H.B. Newman, C. Rogan, M. Spiropulu, V. Timciuc, P. Traczyk, J. Veverka,
R. Wilkinson, Y. Yang, R.Y. Zhu

California Institute of Technology, Pasadena, USA

B. Akgun, V. Azzolini, R. Carroll, T. Ferguson, Y. Iiyama, D.W. Jang, Y.F. Liu, M. Paulini,
H. Vogel, I. Vorobiev

Carnegie Mellon University, Pittsburgh, USA

J.P. Cumalat, B.R. Drell, C.J. Edelmaier, W.T. Ford, A. Gaz, B. Heyburn, E. Luiggi Lopez,
J.G. Smith, K. Stenson, K.A. Ulmer, S.R. Wagner

University of Colorado at Boulder, Boulder, USA

J. Alexander, A. Chatterjee, N. Eggert, L.K. Gibbons, B. Heltsley, A. Khukhunaishvili,
B. Kreis, N. Mirman, G. Nicolas Kaufman, J.R. Patterson, A. Ryd, E. Salvati, W. Sun,
W.D. Teo, J. Thom, J. Thompson, J. Tucker, J. Vaughan, Y. Weng, L. Winstrom, P. Wittich

Cornell University, Ithaca, USA

D. Winn

Fairfield University, Fairfield, USA

S. Abdullin, M. Albrow, J. Anderson, G. Apollinari, L.A.T. Bauerdick, A. Beretvas, J. Berryhill,
P.C. Bhat, I. Bloch, K. Burkett, J.N. Butler, V. Chetluru, H.W.K. Cheung, F. Chlebana,
S. Cihangir, V.D. Elvira, I. Fisk, J. Freeman, Y. Gao, D. Green, O. Gutsche, J. Hanlon,
R.M. Harris, J. Hirschauer, B. Hooberman, S. Jindariani, M. Johnson, U. Joshi, B. Kilminster,
B. Klima, S. Kunori, S. Kwan, C. Leonidopoulos, J. Linacre, D. Lincoln, R. Lipton, J. Lykken,
K. Maeshima, J.M. Marraffino, S. Maruyama, D. Mason, P. McBride, K. Mishra, S. Mrenna,



56 CMS Collaboration / Physics Letters B 725 (2013) 36–59

Y. Musienko 50, C. Newman-Holmes, V. O’Dell, E. Sexton-Kennedy, S. Sharma,
W.J. Spalding, L. Spiegel, P. Tan, L. Taylor, S. Tkaczyk, N.V. Tran, L. Uplegger,
E.W. Vaandering, R. Vidal, J. Whitmore, W. Wu, F. Yang, F. Yumiceva, J.C. Yun

Fermi National Accelerator Laboratory, Batavia, USA

D. Acosta, P. Avery, D. Bourilkov, M. Chen, T. Cheng, S. Das, M. De Gruttola,
G.P. Di Giovanni, D. Dobur, A. Drozdetskiy, R.D. Field, M. Fisher, Y. Fu, I.K. Furic, J. Gartner,
J. Hugon, B. Kim, J. Konigsberg, A. Korytov, A. Kropivnitskaya, T. Kypreos, J.F. Low,
K. Matchev, P. Milenovic 51, G. Mitselmakher, L. Muniz, R. Remington, A. Rinkevicius,
P. Sellers, N. Skhirtladze, M. Snowball, J. Yelton, M. Zakaria

University of Florida, Gainesville, USA

V. Gaultney, S. Hewamanage, L.M. Lebolo, S. Linn, P. Markowitz, G. Martinez, J.L. Rodriguez

Florida International University, Miami, USA

T. Adams, A. Askew, J. Bochenek, J. Chen, B. Diamond, S.V. Gleyzer, J. Haas, S. Hagopian,
V. Hagopian, M. Jenkins, K.F. Johnson, H. Prosper, V. Veeraraghavan, M. Weinberg

Florida State University, Tallahassee, USA

M.M. Baarmand, B. Dorney, M. Hohlmann, H. Kalakhety, I. Vodopiyanov

Florida Institute of Technology, Melbourne, USA

M.R. Adams, I.M. Anghel, L. Apanasevich, Y. Bai, V.E. Bazterra, R.R. Betts, I. Bucinskaite,
J. Callner, R. Cavanaugh, C. Dragoiu, O. Evdokimov, L. Gauthier, C.E. Gerber, D.J. Hofman,
S. Khalatyan, F. Lacroix, M. Malek, C. O’Brien, C. Silkworth, D. Strom, N. Varelas

University of Illinois at Chicago (UIC), Chicago, USA

U. Akgun, E.A. Albayrak, B. Bilki 52, W. Clarida, F. Duru, S. Griffiths, J.-P. Merlo,
H. Mermerkaya 53, A. Mestvirishvili, A. Moeller, J. Nachtman, C.R. Newsom, E. Norbeck,
Y. Onel, F. Ozok, S. Sen, E. Tiras, J. Wetzel, T. Yetkin, K. Yi

The University of Iowa, Iowa City, USA

B.A. Barnett, B. Blumenfeld, S. Bolognesi, D. Fehling, G. Giurgiu, A.V. Gritsan, Z.J. Guo,
G. Hu, P. Maksimovic, S. Rappoccio, M. Swartz, A. Whitbeck

Johns Hopkins University, Baltimore, USA

P. Baringer, A. Bean, G. Benelli, O. Grachov, R.P. Kenny III, M. Murray, D. Noonan,
S. Sanders, R. Stringer, G. Tinti, J.S. Wood, V. Zhukova

The University of Kansas, Lawrence, USA

A.F. Barfuss, T. Bolton, I. Chakaberia, A. Ivanov, S. Khalil, M. Makouski, Y. Maravin,
S. Shrestha, I. Svintradze

Kansas State University, Manhattan, USA

J. Gronberg, D. Lange, D. Wright

Lawrence Livermore National Laboratory, Livermore, USA

A. Baden, M. Boutemeur, B. Calvert, S.C. Eno, J.A. Gomez, N.J. Hadley, R.G. Kellogg, M. Kirn,
T. Kolberg, Y. Lu, M. Marionneau, A.C. Mignerey, K. Pedro, A. Peterman, A. Skuja, J. Temple,
M.B. Tonjes, S.C. Tonwar, E. Twedt

University of Maryland, College Park, USA



CMS Collaboration / Physics Letters B 725 (2013) 36–59 57

A. Apyan, G. Bauer, J. Bendavid, W. Busza, E. Butz, I.A. Cali, M. Chan, V. Dutta,
G. Gomez Ceballos, M. Goncharov, K.A. Hahn, Y. Kim, M. Klute, K. Krajczar 54, W. Li,
P.D. Luckey, T. Ma, S. Nahn, C. Paus, D. Ralph, C. Roland, G. Roland, M. Rudolph,
G.S.F. Stephans, F. Stöckli, K. Sumorok, K. Sung, D. Velicanu, E.A. Wenger, R. Wolf,
B. Wyslouch, S. Xie, M. Yang, Y. Yilmaz, A.S. Yoon, M. Zanetti

Massachusetts Institute of Technology, Cambridge, USA

S.I. Cooper, B. Dahmes, A. De Benedetti, G. Franzoni, A. Gude, S.C. Kao, K. Klapoetke,
Y. Kubota, J. Mans, N. Pastika, R. Rusack, M. Sasseville, A. Singovsky, N. Tambe, J. Turkewitz

University of Minnesota, Minneapolis, USA

L.M. Cremaldi, R. Kroeger, L. Perera, R. Rahmat, D.A. Sanders

University of Mississippi, Oxford, USA

E. Avdeeva, K. Bloom, S. Bose, J. Butt, D.R. Claes, A. Dominguez, M. Eads, J. Keller,
I. Kravchenko, J. Lazo-Flores, H. Malbouisson, S. Malik, G.R. Snow

University of Nebraska-Lincoln, Lincoln, USA

U. Baur, A. Godshalk, I. Iashvili, S. Jain, A. Kharchilava, A. Kumar, S.P. Shipkowski, K. Smith

State University of New York at Buffalo, Buffalo, USA

G. Alverson ∗, E. Barberis, D. Baumgartel, M. Chasco, J. Haley, D. Nash, D. Trocino,
D. Wood, J. Zhang

Northeastern University, Boston, USA

A. Anastassov, A. Kubik, N. Mucia, N. Odell, R.A. Ofierzynski, B. Pollack, A. Pozdnyakov,
M. Schmitt, S. Stoynev, M. Velasco, S. Won

Northwestern University, Evanston, USA

L. Antonelli, D. Berry, A. Brinkerhoff, M. Hildreth, C. Jessop, D.J. Karmgard, J. Kolb,
K. Lannon, W. Luo, S. Lynch, N. Marinelli, D.M. Morse, T. Pearson, R. Ruchti, J. Slaunwhite,
N. Valls, M. Wayne, M. Wolf

University of Notre Dame, Notre Dame, USA

B. Bylsma, L.S. Durkin, C. Hill, R. Hughes, R. Hughes, K. Kotov, T.Y. Ling, D. Puigh,
M. Rodenburg, C. Vuosalo, G. Williams, B.L. Winer

The Ohio State University, Columbus, USA

N. Adam, E. Berry, P. Elmer, D. Gerbaudo, V. Halyo, P. Hebda, J. Hegeman, A. Hunt,
P. Jindal, D. Lopes Pegna, P. Lujan, D. Marlow, T. Medvedeva, M. Mooney, J. Olsen,
P. Piroué, X. Quan, A. Raval, B. Safdi, H. Saka, D. Stickland, C. Tully, J.S. Werner, A. Zuranski

Princeton University, Princeton, USA

J.G. Acosta, E. Brownson, X.T. Huang, A. Lopez, H. Mendez, S. Oliveros, J.E. Ramirez Vargas,
A. Zatserklyaniy

University of Puerto Rico, Mayaguez, USA

E. Alagoz, V.E. Barnes, D. Benedetti, G. Bolla, D. Bortoletto, M. De Mattia, A. Everett, Z. Hu,
M. Jones, O. Koybasi, M. Kress, A.T. Laasanen, N. Leonardo, V. Maroussov, P. Merkel,
D.H. Miller, N. Neumeister, I. Shipsey, D. Silvers, A. Svyatkovskiy, M. Vidal Marono,



58 CMS Collaboration / Physics Letters B 725 (2013) 36–59

H.D. Yoo, J. Zablocki, Y. Zheng

Purdue University, West Lafayette, USA

S. Guragain, N. Parashar

Purdue University Calumet, Hammond, USA

A. Adair, C. Boulahouache, K.M. Ecklund, F.J.M. Geurts, B.P. Padley, R. Redjimi, J. Roberts,
J. Zabel

Rice University, Houston, USA

B. Betchart, A. Bodek, Y.S. Chung, R. Covarelli, P. de Barbaro, R. Demina, Y. Eshaq,
A. Garcia-Bellido, P. Goldenzweig, J. Han, A. Harel, D.C. Miner, D. Vishnevskiy, M. Zielinski

University of Rochester, Rochester, USA

A. Bhatti, R. Ciesielski, L. Demortier, K. Goulianos, G. Lungu, S. Malik, C. Mesropian

The Rockefeller University, New York, USA

S. Arora, A. Barker, J.P. Chou, C. Contreras-Campana, E. Contreras-Campana, D. Duggan,
D. Ferencek, Y. Gershtein, R. Gray, E. Halkiadakis, D. Hidas, A. Lath, S. Panwalkar, M. Park,
R. Patel, V. Rekovic, J. Robles, K. Rose, S. Salur, S. Schnetzer, C. Seitz, S. Somalwar,
R. Stone, S. Thomas

Rutgers, The State University of New Jersey, Piscataway, USA

G. Cerizza, M. Hollingsworth, S. Spanier, Z.C. Yang, A. York

University of Tennessee, Knoxville, USA

R. Eusebi, W. Flanagan, J. Gilmore, T. Kamon 55, V. Khotilovich, R. Montalvo, I. Osipenkov,
Y. Pakhotin, A. Perloff, J. Roe, A. Safonov, T. Sakuma, S. Sengupta, I. Suarez, A. Tatarinov,
D. Toback

Texas A&M University, College Station, USA

N. Akchurin, J. Damgov, P.R. Dudero, C. Jeong, K. Kovitanggoon, S.W. Lee, T. Libeiro, Y. Roh,
I. Volobouev

Texas Tech University, Lubbock, USA

E. Appelt, A.G. Delannoy, C. Florez, S. Greene, A. Gurrola, W. Johns, C. Johnston, P. Kurt,
C. Maguire, A. Melo, M. Sharma, P. Sheldon, B. Snook, S. Tuo, J. Velkovska

Vanderbilt University, Nashville, USA

M.W. Arenton, M. Balazs, S. Boutle, B. Cox, B. Francis, J. Goodell, R. Hirosky, A. Ledovskoy,
C. Lin, C. Neu, J. Wood, R. Yohay

University of Virginia, Charlottesville, USA

S. Gollapinni, R. Harr, P.E. Karchin, C. Kottachchi Kankanamge Don, P. Lamichhane,
A. Sakharov

Wayne State University, Detroit, USA

M. Anderson, M. Bachtis, D.A. Belknap, L. Borrello, D. Carlsmith, M. Cepeda, S. Dasu,
E. Friis, L. Gray, K.S. Grogg, M. Grothe, R. Hall-Wilton, M. Herndon, A. Hervé, P. Klabbers,
J. Klukas, A. Lanaro, C. Lazaridis, J. Leonard, R. Loveless, A. Mohapatra, I. Ojalvo,



CMS Collaboration / Physics Letters B 725 (2013) 36–59 59

F. Palmonari, G.A. Pierro, I. Ross, A. Savin, W.H. Smith, J. Swanson

University of Wisconsin, Madison, USA

* Corresponding author.
E-mail address: George.Alverson@cern.ch (G. Alverson).

† Deceased.
1 Also at Vienna University of Technology, Vienna, Austria.
2 Also at National Institute of Chemical Physics and Biophysics, Tallinn, Estonia.
3 Also at California Institute of Technology, Pasadena, USA.
4 Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland.
5 Also at Laboratoire Leprince-Ringuet, Ecole Polytechnique, IN2P3–CNRS, Palaiseau, France.
6 Also at Suez Canal University, Suez, Egypt.
7 Also at Zewail City of Science and Technology, Zewail, Egypt.
8 Also at Cairo University, Cairo, Egypt.
9 Also at Fayoum University, El-Fayoum, Egypt.

10 Also at British University in Egypt, Cairo, Egypt.
11 Now at Ain Shams University, Cairo, Egypt.
12 Also at National Centre for Nuclear Research, Swierk, Poland.
13 Also at Université de Haute Alsace, Mulhouse, France.
14 Now at Joint Institute for Nuclear Research, Dubna, Russia.
15 Also at Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia.
16 Also at Brandenburg University of Technology, Cottbus, Germany.
17 Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary.
18 Also at Eötvös Loránd University, Budapest, Hungary.
19 Also at Tata Institute of Fundamental Research – HECR, Mumbai, India.
20 Also at University of Visva-Bharati, Santiniketan, India.
21 Also at Sharif University of Technology, Tehran, Iran.
22 Also at Isfahan University of Technology, Isfahan, Iran.
23 Also at Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran.
24 Also at Facoltà Ingegneria, Università di Roma, Roma, Italy.
25 Also at Università degli Studi Guglielmo Marconi, Roma, Italy.
26 Also at Università degli Studi di Siena, Siena, Italy.
27 Also at University of Bucharest, Faculty of Physics, Bucuresti-Magurele, Romania.
28 Also at Faculty of Physics, University of Belgrade, Belgrade, Serbia.
29 Also at University of California, Los Angeles, USA.
30 Also at Scuola Normale e Sezione dell