Mori, F. [UNESP]2014-05-272014-05-271996-12-01Modern Physics Letters A, v. 11, n. 9, p. 715-722, 1996.0217-7323http://hdl.handle.net/11449/64923We examine further astrophysical constraints on a light spinless particle coupled only to photons and proposed by Massó and Toldra. We consider constraints coming from measurements of extra galactic background and from ionization of HI clouds.715-722engArtigo10.1142/S0217732396000710WOS:A1996UL33800002Acesso restrito2-s2.0-0000443430