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تسجيل مستخدم جديدProperties of the redback millisecond pulsar binary 3FGL J0212.1+5320
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Linares et al. (2016) obtained quasi-simultaneous g, r and i-band light curves and an absorption line radial velocity curve of the secondary star in the redback system 3FGL J0212.1+5320. The light curves showed two maxima and minima primarily due to the secondary stars ellipsoidal modulation, but with unequal maxima and minima. We fit these light curves and radial velocities with our X-ray binary model including either a dark solar-type star spot or a hot spot due to off-centre heating from an intrabinary shock, to account for the unequal maxima. Both models give a radial velocity semi-amplitude and rotational broadening that agree with the observations. The observed secondary stars effective temperature is best matched with the value obtained using the hot spot model, which gives a neutron star and secondary star mass of $M_{rm 1}$=1.85$^{+0.32}_{-0.26}$ $M_{odot}$and $M_{rm 2}$=0.50$^{+0.22}_{-0.19}$ $M_{odot}$, respectively.
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We present a multi-wavelength study of the unidentified Fermi object, 3FGL J0212.1+5320. Within the 95% error ellipse, Chandra detects a bright X-ray source (i.e., F(0.5-7keV) = 1.4e-12 erg/cm^2/s), which has a low-mass optical counterpart (M < 0.4 M
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