INTERNATIONAL JOURNAL OF MODERN PHYSICS D, vol.18, no.13, pp.1991-2006, 2009 (SCI-Expanded)
In this work, the results of X-ray spectral analysis of radio-quiet X-ray pulsar 1E 1207.4-5209 and RX J0002+6246, RX J0822-4300, CXOU J185238.6+00402, which have the same observational characteristics as 1E 1207.4-5209, are represented based on XMM-Newton satellite observations. These four neutron stars with common physical properties may have similar physical evolution. It is shown that all of them have Pure blackbody spectra (two-blackbody fits in three cases) without a power law component. No pulsar wind nebula has been observed around any one of them, which strongly shows that they have low rotational energy loss despite their small ages. All of these neutron stars are physically connected to shell-type supernova remnants which are younger than (1-2) x 10(4) yr. None of these sources has been detected to emit at radiofrequencies. These common spectral properties (and possibly common timing characteristics) of these neutron stars are examined. Their possible evolution is discussed based on a model represented in Ref. 1. As a result, it is quite possible that these objects form a new class of neutron stars quite different than the other types.