Neutron Stars (NSs) are born as hot, lepton-rich objects that evolve according to the standard paradigm through subsequent stages where they radiate the excess of energy by emitting, first, neutrinos and, later on, photons. Current descriptions based on Standard Model calculations cannot fully explain all the existing cooling data series for the dozens of objects that have been reported. In this work, we consider the intriguing possibility that cooling NSs could be actually admixed with a fraction of light dark matter (LDM), $χ$. We focus on a particular case study assuming a generic light candidate with mass $m_χ=0.1$ $\rm GeV/c^2$ that undergoes self-annihilating reactions through pseudoscalar mediators producing neutrinos in the final state. We include one additional feature, allowing thermal conduction from LDM while inside the dark core. By performing simulations of the temperature evolution in the NS, we find that cooling patterns could be distorted by the presence of LDM and discuss these results in light of their observability.
Universal relation involving fundamental modes in two-fluid dark matter admixed neutron stars
Kochi University(高知大学);RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS), RIKEN(理化学研究所交叉理论数学科学中心(iTHEMS));Theoretical Astrophysics, IAAT, University of Tübingen(蒂宾根大学天体物理研究所)
Observables and conformal properties of dark matter admixed isentropic neutron stars
Indian Institute of Science Education and Research Thiruvananthapuram(印度科学教育研究所特里凡得琅分校);California State University Long Beach(加州州立大学长滩分校);Université de Caen Normandie(诺曼底卡昂大学)
Two-fluid $f$-mode oscillations of dark-matter-admixed neutron stars
Institute of Astrophysics, Central China Normal University(华中师范大学天文物理研究所);School of Optoelectronic Information Engineering, Institute of Astronomy and High Energy Physics, Hubei University of Education(湖北教育学院光电信息工程学院、天体与高能物理研究所);School of Mathematics and Physics, China University of Geosciences(中国地质大学数学与物理学院);School of Physics, Huazhong University of Science and Technology(华中科技大学物理学院);INFN Sezione di Catania, Dipartimento di Fisica, Universitá di Catania(意大利国家核物理研究院卡塔尼亚分部、卡塔尼亚大学物理系)
Scalar and vector dark matter admixed neutron stars with linear and quadratic couplings
Università di Salerno(萨莱诺大学);INFN, Gruppo collegato di Salerno(意大利国家核物理研究所萨莱诺协作组);Institute for Particle Physics Phenomenology (IPPP), Department of Physics, Durham University(达勒姆大学粒子物理现象学研究所)
Density-induced dark-baryon conversion in $Δ-$admixed hypernuclear neutron stars
Birangana Sati Sadhani Rajyik Vishwavidyalaya(比朗加纳·萨蒂·萨达尼·皇家大学);Indian Institute of Science Education and Research, Tirupati(印度科学教育与研究学院提鲁帕提分校);Wroclaw University of Science and Technology(弗罗茨瓦夫科技大学);Institute of Theoretical Physics, Wroclaw University of Science and Technology(弗罗茨瓦夫科技大学理论物理研究所);Physical Research Laboratory(物理研究实验室)
Finite-Temperature Axion-Admixed Neutron Stars in a Quarkyonic Crossover Framework
Institute of Physics, Sachivalaya Marg, Bhubaneswar-751005, India(印度布巴内斯瓦尔物理研究所);Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India(印度孟买霍米巴巴哈国立研究所);Department of Physics, Indira Gandhi Institute of Technology, Sarang, Dhenkanal, Odisha-759146, India(印度奥迪沙邦德赫卡纳尔萨拉格英迪拉甘地理工学院物理系)
U-spin symmetry energy and hyperon puzzle in $Λ$-admixed neutron stars
Tsung-Dao Lee Institute, Shanghai Jiao Tong University(上海交大李政道研究所);Center for Gravitation and Cosmology, College of Physical Science and Technology, Yangzhou University(扬州大学物理科学与技术学院引力与宇宙学中心);School of Physics and Astronomy, Shanghai Jiao Tong University(上海交通大学物理与天文学院);State Key Laboratory of Dark Matter Physics, Shanghai Jiao Tong University(上海交通大学暗物质物理国家重点实验室);Kavli Institute for Astronomy and Astrophysics, Peking University(北京大学科维理天文与天体物理研究所);School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University(北京大学物理学院核物理与技术国家重点实验室)
Enhanced Neutrino Cooling from Parity-Doubled Nucleons in Neutron Star Cooling Simulations
Catholic Institute of Technology(天主教理工学院);Universidade Federal Fluminense(弗鲁米嫩塞联邦大学);ICRANet(国际相对论天体物理中心网络);Washington University in St. Louis(圣路易斯华盛顿大学);Frankfurt Institute for Advanced Studies (FIAS)(法兰克福高等研究所);GSI Helmholtzzentrum für Schwerionenforschung GmbH(德国重离子研究中心);Kent State University(肯特州立大学);Brookhaven National Laboratory(布鲁克海文国家实验室)
The impact of magnetic field on the thermal evolution of neutron stars
研究了B> 10 e 13 G的强磁场对中子星热演化的影响,包括磁场衰变引起的地壳加热。为此,我们进行了二维冷却模拟与各向异性的热导率考虑所有相关的中微子发射过程的现实中子星。中子星的标准冷却模型受到质疑,显示磁场有相关的(在许多情况下占主导地位的)热演化的影响。磁场的存在显着影响的热表面分布和冷却的历史,这些对象期间,早期中微子冷却时代和后期光子冷却时代。因此,最小冷却方案比通常假设的更复杂。磁化中子星的一致的磁热演化需要解释观测结果。
Neutron Star Cooling via Axion Emission by Nucleon-Nucleon Axion Bremsstrahlung
中子星通常通过发射伽马射线和中微子而冷却。但是,在中子星内部,也可以通过核子-核子轴子韧致辐射过程产生轴子。这些轴子的逃逸增加了中子星的冷却过程。我们探讨了中子星冷却的本质,包括轴子发射和比较我们的结果与情况下,中子星冷却的伽玛射线和中微子的排放。在我们的计算中,我们考虑了这种轴子能量损失率的简并和非简并极限以及由此产生的中子星的光度随时间的变化和表面温度随时间的变化。简而言之,我们研究了三种中子星质量(1.0,1.4,1.8太阳质量)的中子星的热演化,并考虑了不同质量的轴子($m_{a}=10^{-5}\rm{eV}, 10^{-3}\rm{eV}, 10^{-2}\rm{eV}$)的轴子辐射的影响,并与不考虑轴子辐射的情况进行了比较。我们将理论冷却曲线与PSR B 056 +14、Geminga和PSR B 1055 -52的观测数据进行了比较,最后给出了轴子质量极限$m_{a}\leq10^{-3}$ eV的一个上界,即轴子衰变常数$f_{a}\geq0.6\times10^{10}\hspace{1mm}\rm{GeV}$。
Limit on the Axion Decay Constant from the Cooling Neutron Star in Cassiopeia A
位于超新星遗迹仙后座A(Cas A)中心的中子星(NS)观测到的快速冷却可以用最小NS冷却方案来解释。如果存在一个额外的冷源,如轴子发射,这一结果可能会改变。在这项工作中,我们研究了在轴子发射存在下的Cas A NS冷却,考虑到在整个寿命的Cas A NS的温度演化。我们得到的轴子衰变常数,$f_a\gtrsim (5-7)\times 10^8$ GeV的下限,如果恒星有一个薄碳层的信封。这与SN1987A等其他天体物理观测所施加的现有限制一样强大。