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Register a new userDiscovery of an X-ray nebula in the field of millisecond pulsar PSR J1911-1114
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Jongsu Lee
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We have discovered an extended X-ray feature which is apparently associated with millisecond pulsar (MSP) PSR J1911-1114 from a XMM-Newton observation, which extends for ~1 and the radio timing position of PSR J1911-1114 is in the mid point of the feature. The orientation of the feature is similar to the proper motion direction of PSR J1911-1114. Its X-ray spectrum can be well-modeled by an absorbed power-law with a photon index of $Gamma=1.8^{+0.3}_{-0.2}$. If this feature is confirmed to be a pulsar wind nebula (PWN), this will be the third case that an X-ray PWN found to be powered by a MSP.
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We report multi-wavelength observations of the unidentified Fermi object 2FGL J1653.6-0159. With the help of high-resolution X-ray observation, we have identified an X-ray and optical counterpart of 2FGL J1653.6-0159. The source exhibits a periodic modulation of 75 min in optical and possibly also in X-ray. We suggest that 2FGL J1653.6-0159 is a compact binary system with an orbital period of 75 min. Combining the gamma-ray and X-ray properties, 2FGL J1653.6-0159 is potentially a black widow/redback type gamma-ray millisecond pulsar (MSP). The optical and X-ray lightcurve profiles show that the companion is mildly heated by the high-energy emission and the X-rays are from intrabinary shock. Although no radio pulsation has been detected yet, we estimated that the spin period of the MSP is ~2ms based on a theoretical model. If pulsation can be confirmed in the future, 2FGL J1653.6-0159 will become the first ultracompact rotation-powered MSP.
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