Millisecond Pulsar Origin of the Galactic Center Excess and Extended Gamma-Ray Emission from Andromeda: A Closer Look
Millisecond Pulsar Origin of the Galactic Center Excess and Extended Gamma-Ray Emission from Andromeda: A Closer Look
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银河系中心过量的毫秒脉冲星起源和仙女座星系的扩展伽马射线发射：近距离观察
DOI：
10.3847/1538-4357/aac029
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发表时间：
2017-11
期刊：
影响因子：
--
通讯作者：
enbroucke
中科院分区：
文献类型：
--
作者：
Christopher Eckner;Xian Hou;Pasquale D. Serpico;Miles Winter;Gabrijela Zaharijas;Pierrick Martin;Mattia di Mauro;Nestor Mirabal;Jovana Petrovic;Tijana Prodanovic;Justin V;enbroucke
最近，费米-LAT合作组织发表了对仙女座星系（M31）中心空间扩展伽马射线信号的新测量，报告称该发射与银河系（MW）的所谓银河系中心过剩（GCE）大致相似。证据的重量是稳步积累毫秒脉冲星（MSP）起源的GCE。这些元素促使我们将这些观测结果与也许是最简单的MSP种群模型进行比较，该模型仅通过重新调整MSP光度函数来获得，该函数是通过系统各自的恒星质量在本地MW盘中确定的。值得注意的是，我们发现，没有自由拟合参数，这个模型可以解释的能量和形态的GCE内的不确定性。对于M31，原始MSP的估计亮度预计仅占探测到的发射量的四分之一，尽管考虑到很大的不确定性，不能排除更强的贡献。如果正确的话，该模型预测M31盘发射由于MSP是不是远低于目前的上限。我们还讨论了这个简单模型的其他改进。利用球状星团伽玛射线光度与恒星相遇率之间的相关性，我们测量了球状星团球核中MSP的动力学形成。预计该成分仅在0.5%的水平上对GCE有贡献，它可能影响信号的形态。我们还评论了我们的模型的局限性和未来的前景，以改善诊断。
A new measurement of a spatially extended gamma-ray signal from the center of the Andromeda galaxy (M31) has recently been published by the Fermi-LAT collaboration, reporting that the emission broadly resembles the so-called Galactic center excess (GCE) of the Milky Way (MW). The weight of the evidence is steadily accumulating on a millisecond pulsar (MSPs) origin for the GCE. These elements prompt us to compare these observations with what is, perhaps, the simplest model for an MSP population, which is solely obtained by rescaling of the MSP luminosity function that is determined in the local MW disk via the respective stellar mass of the systems. Remarkably, we find that without free fitting parameters, this model can account for both the energetics and the morphology of the GCE within uncertainties. For M31, the estimated luminosity due to primordial MSPs is expected to only contribute about a quarter of the detected emission, although a stronger contribution cannot be excluded given the large uncertainties. If correct, the model predicts that the M31 disk emission due to MSPs is not far below the present upper bound. We also discuss additional refinements of this simple model. Using the correlation between globular cluster gamma-ray luminosity and stellar encounter rate, we gauge the dynamical MSP formation in the bulge. This component is expected to contribute to the GCE only at a level of ≲5%, it could affect the signal’s morphology. We also comment on the limitations of our model and on future perspectives for improved diagnostics.
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影响因子：
14.1
作者：
R. Bartels;E. Storm;C. Weniger;F. Calore
通讯作者：
R. Bartels;E. Storm;C. Weniger;F. Calore
DOI：
10.1088/0004-637x/802/2/124
发表时间：
2014-11
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Q. Yuan;K. Ioka
通讯作者：
Q. Yuan;K. Ioka
银河系中心伽马射线过剩的毫秒脉冲星解释
影响因子：
3.8
作者：
Yuan, Qiang;Zhang, Bing
通讯作者：
Zhang, Bing
DOI：
10.1016/j.dark.2013.06.003
发表时间：
2013-02
期刊：
arXiv: High Energy Astrophysical Phenomena
影响因子：
--
作者：
D. Hooper;T. Slatyer
通讯作者：
D. Hooper;T. Slatyer
影响因子：
4.8
作者：
J. Binney;W. Dehnen
通讯作者：
J. Binney;W. Dehnen