Foreground mismodeling and the point source explanation of the Fermi Galactic Center excess
Foreground mismodeling and the point source explanation of the Fermi Galactic Center excess
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费米银河中心过剩的前景错误建模和点源解释
DOI：
10.1103/physrevd.102.023023
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发表时间：
2020
影响因子：
5
通讯作者：
Macias, Oscar
中科院分区：
文献类型：
--
作者：
Buschmann, Malte;Rodd, Nicholas L.;Safdi, Benjamin R.;Chang, Laura J.;Mishra-Sharma, Siddharth;Lisanti, Mariangela;Macias, Oscar
费米大区域望远镜观测到来自银河系中心的过剩能量伽马射线，这可能是由近热暗物质湮灭引起的。然而，确定这种过剩的暗物质来源是复杂的，因为在对漫射宇宙线前景以及未分辨的天体物理源(如毫秒脉冲星)进行建模方面存在挑战。非泊松模板拟合(NPTF)是一种统计技术，以前曾被用来表明GeV过剩的至少一部分可能是由于暗点源的总体。这些结果最近受到Leane和Slatyer(2019)的质疑，他们表明，注入到realFermidata上的合成暗物质湮灭信号无法通过NPTF程序恢复。在这项工作中，我们对费米数据进行了专门的研究，并明确表明Leane和Slatyer(2019)的中心结果很可能是因为他们为银河系前景发射选择的模型没有提供足够好的数据描述。我们使用最先进的银河系漫射伽马射线发射模型重复了NPTF分析，并引入了一种新的统计程序，基于球谐边际化，以数据驱动的方式提供了对银河系漫射发射的改进描述。有了这些改进，我们发现NPTF的结果继续有力地支持这样的解释，即银河系中心过剩部分是由于我们所探索的分析变化中未解决的天体物理点源。
TheFermiLarge Area Telescope has observed an excess ofenergy gamma rays from the center of the Milky Way, which may arise from near-thermal dark matter annihilation. Firmly establishing the dark matter origin for this excess is however complicated by challenges in modeling diffuse cosmic-ray foregrounds as well as unresolved astrophysical sources, such as millisecond pulsars. Non-Poissonian template fitting (NPTF) is one statistical technique that has previously been used to show that at least some fraction of the GeV excess is likely due to a population of dim point sources. These results were recently called into question by Leane and Slatyer (2019), who showed that a synthetic dark matter annihilation signal injected on top of the realFermidata is not recovered by the NPTF procedure. In this work, we perform a dedicated study of theFermidata and explicitly show that the central result of Leane and Slatyer (2019) is likely driven by the fact that their choice of model for the Galactic foreground emission does not provide a sufficiently good description of the data. We repeat the NPTF analyses using a state-of-the-art model for diffuse gamma-ray emission in the Milky Way and introduce a novel statistical procedure, based on spherical-harmonic marginalization, to provide an improved description of the Galactic diffuse emission in a data-driven fashion. With these improvements, we find that the NPTF results continue to robustly favor the interpretation that the Galactic Center excess is due, in part, to unresolved astrophysical point sources across the analysis variations that we have explored.
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影响因子：
6.5
作者：
Ben Bekhti, N.;Floer, L.;Staveley-Smith, L.
通讯作者：
Staveley-Smith, L.
哈勃深场北区钱德拉观测的离源涨落分析的微弱源计数
DOI：
10.1086/338794
发表时间：
2001
期刊：
The Astrophysical Journal Letters
影响因子：
--
作者：
T. Miyaji;R. Griffiths
通讯作者：
R. Griffiths
漫射 Y 射线发射的费米-LAT 观测：对宇宙射线和星际介质的影响
影响因子：
4.9
作者：
Ackermann;M;et al
通讯作者：
et al
暗物质子结构无法解释费米银河中心过剩的特性
影响因子：
6.4
作者：
H. Clark;P. Scott;R. Trotta;G. Lewis
通讯作者：
G. Lewis
影响因子：
8.7
作者：
Abdollahi, S.;Acero, F.;Zaharijas, G.
通讯作者：
Zaharijas, G.