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arXiv 1106.2140astro-ph.HE
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Calvera是一颗Gamma-ray脉冲星吗?

Is Calvera a Gamma-ray Pulsar?

J. P. Halpern

摘要:

1 RXS J141256.0+792204(“Calvera”)最初在ROSAT全天巡天中被选为中子星(NS)候选星,在一对XMM-牛顿观测中被发现是一颗59毫秒的X射线脉冲星(Zane等人,2011年)。令人惊讶的是,他们声称在费米伽马射线数据中检测到这颗脉冲星不需要周期导数,严重限制了它的偶极磁场强度,自旋下降光度和距离。这意味着Calvera的冷却年龄比其特征性的自旋下降年龄要年轻得多。如果是这样的话,它可能是一颗轻度回收的脉冲星,或者是第一颗“孤儿”中心致密天体(CCO)。在这里,我们表明,公布的费米星历未能对齐的脉冲相位的两个X射线观测彼此,这表明费米探测几乎肯定是虚假的。对额外费米数据的分析也没有证实伽马射线的探测。这使得卡尔韦拉的自旋下降速率受到较少的限制,并且它在NS家族中的位置不确定。它仍然可能是一颗正常的脉冲星,一颗轻度回收的脉冲星,或者一颗孤儿CCO。

英文摘要:

Originally selected as a neutron star (NS) candidate in the ROSAT All-Sky Survey, 1RXS J141256.0+792204 ("Calvera") was discovered to be a 59 ms X-ray pulsar in a pair of XMM-Newton observations (Zane et al. 2011). Surprisingly, their claimed detection of this pulsar in Fermi gamma-ray data requires no period derivative, severely restricting its dipole magnetic field strength, spin-down luminosity, and distance to small values. This implies that the cooling age of Calvera is much younger than its characteristic spin-down age. If so, it could be a mildly recycled pulsar, or the first "orphaned" central compact object (CCO). Here we show that the published Fermi ephemeris fails to align the pulse phases of the two X-ray observations with each other, which indicates that the Fermi detection is almost certainly spurious. Analysis of additional Fermi data also does not confirm the gamma-ray detection. This leaves the spin-down rate of Calvera less constrained, and its place among the families of NSs uncertain. It could still be either a normal pulsar, a mildly recycled pulsar, or an orphaned CCO.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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