In this paper we propose a dark matter model and study aspects of its phenomenology. Our model is based on a new dark matter sector with a U(1)' gauge symmetry plus a discrete symmetry added to the Standard Model of particle physics. The new fields of the dark matter sector have no hadronic charges and couple only to leptons. Our model can not only give rise to the observed neutrino mass hierarchy, but can also generate the baryon number asymmetry via non-thermal leptogenesis. The breaking of the new U(1)' symmetry produces cosmic strings. The dark matter particles are produced non-thermally from cosmic string loop decay which allows one to obtain sufficiently large annihilation cross sections to explain the observed cosmic ray positron and electron fluxes recently measured by the PAMELA, ATIC, PPB-BETS, Fermi-LAT, and HESS experiments while maintaining the required overall dark matter energy density. The high velocity of the dark matter particles from cosmic string loop decay leads to a low phase space density and thus to a dark matter profile with a constant density core in contrast to what happens in a scenario with thermally produced cold dark matter where the density keeps rising towards the center. As a result, the flux of gamma rays radiated from the final leptonic states of dark matter annihilation from the Galactic center is suppressed and satisfies the constraints from the HESS gamma-ray observations.
Diffuse Gamma Rays from WIMP Decay and Annihilation
我讨论了弱相互作用大质量粒子（WIMPs）的衰变和湮灭对漫射伽马射线背景的贡献。首先回顾了WIMP的宇宙学丰度的计算，并指出它与WIMP湮灭成较轻粒子的截面简单相关。讨论了WIMP衰变产生的河外背景辐射。我展示了如何观测上限的DEBRA可以用来约束衰减到光子的WIMP的属性，我提出了额外的新的约束，湮灭截面的酉性强加在这样的粒子。然后，我讨论伽马射线湮灭的弱相互作用粒子在晕，球状体，和磁盘的我们的星系，以及那些从弱相互作用粒子湮灭在大麦云云。(To出现在The Gamma Ray Sky with Compton GRO and SIGMA，Proceedings of the School，Les Houches，France，January 25-February 4，1994中。
The impact of gamma-ray propagation effects on indirect dark matter searches
Universidad Autónoma de Madrid（马德里自治大学）；Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT)（能源、环境和技术中心）；Instituto de Física Teórica, IFT UAM-CSIC（理论物理研究所）；Institut d’Astrophysique de Paris, Sorbonne Université（巴黎天体物理学研究所，索邦大学）；Laboratoire de Physique Nucléaire et des Hautes Énergies, Sorbonne Université（核物理与高能实验室，索邦大学）
The WIMP proposed here yields the observed abundance of dark matter, and is consistent with the current limits from direct detection, indirect detection, and collider experiments, if its mass is $\sim 72$ GeV/$c^2$. It is also consistent with analyses of the gamma rays observed by Fermi-LAT from the Galactic center (and other sources), and of the antiprotons observed by AMS-02, in which the excesses are attributed to dark matter annihilation. These successes are shared by the inert doublet model (IDM), but the phenomenology is very different: The dark matter candidate of the IDM has first-orde…
SUSY under siege from direct and indirect WIMP detection experiments
我们通过直接和间接的暗物质搜索实验，研究了在超对称模型中检测WIMP的最新前景。我们研究了几个历史和仍然可行的方案：预测良好的回火中性子（WTN），预测从MasterCode（MC），贝叶斯拟合（BF）和Fittino（FO）的合作，非热wino暗物质（NThW），最后混合轴子higgsino暗物质从超对称性与辐射驱动的自然性（RNS）。由于XENON和LUX合作的最新限制，WTN被排除在外。NThW的情况下，以前在脆弱的地面上，由于伽马线搜索，似乎也排除了最近的结合费米-LAT/MAGIC限制结合新的HESS结果从连续伽马射线。从BF群中排除了MC参数空间和1 TeV higgsino参数空间的大部分。来自RNS的100-300 GeV的类希格斯诺弱相互作用粒子由于其可能的耗尽的局部丰度而幸存下来（在那里轴子可能构成了大部分的暗物质）。吨级稀有液体探测器的预测应该发现或排除这些幸存模型的剩余参数空间的WIMP。
我回顾了几个建议的技术间接检测弱相互作用的大质量粒子（WIMPs）的晕。我专注于宇宙射线正电子，反质子和伽马射线的独特签名产生的湮灭的WIMP在星系晕。(To出现在Particle Astrophysics，原子物理学，and Gravitation}，Proceedings of the XIVth Moriond Workshop，Villars sur Ollon，Switzerland，Jan.22 -29，1994。
Indirect searches for signatures of corpuscular dark matter have been performed using all cosmic messengers: gamma rays, cosmic rays, and neutrinos. The search for dark matter from neutrinos is of particular importance since they are the only courier that can reach detectors from dark matter processes in dense environments, such as the core of the Sun or Earth, or from the edge of the observable Universe. In this work, we introduce $χ$aro$ν$, a software package that, in the spirit of its mythological Greek namesake $χ\acuteαρων$, bridges the dark sector and Standard Model by predicting neutrin…
Over the past decades Bayesian methods have become increasingly popular in astronomy and physics as stochastic samplers have enabled efficient investigation of high-dimensional likelihood surfaces. In this work we develop a hierarchical Bayesian inference framework to detect the presence of dark matter annihilation events in data from the Cherenkov Telescope Array (CTA). Cosmic rays are weighted based on their measured sky position $\hatΩ_m$ and energy $E_m$ in order to derive a posterior distribution for the dark matter's velocity averaged cross section $\langleσv\rangle$. The dark matter sig…
TeV-scale particles that couple to the standard model through the weak force represent a compelling class of dark matter candidates. The search for such Weakly Interacting Massive Particles (WIMPs) has already spanned multiple decades, and whilst it has yet to provide any definitive evidence for their existence, viable parameter space remains. In this paper, we show that the upcoming Cherenkov Telescope Array (CTA) has significant sensitivity to uncharted parameter space at the TeV mass scale. To do so, we focus on two prototypical dark matter candidates, the Wino and Higgsino. Sensitivity for…
Dwarf galaxies are dark matter-dominated and therefore promising targets for the search for weakly interacting massive particles (WIMPs), which are well-known candidates for dark matter. Annihilation of WIMPs produce ultra-relativistic cosmic-ray electrons and positrons that emit synchrotron radiation in the presence of magnetic fields. For typical magnetic field strengths (few $μ$G) and $\mathcal O$(GeV--TeV) WIMP masses, this emission peaks at hundreds of MHz. Here, we use the non-detection of 150-MHz radio continuum emission from the dwarf spheroidal galaxy Canes Venatici I with the LOw-Fre…
We assess the status of a wide class of WIMP dark matter (DM) models in light of the latest experimental results using the global fitting framework $\textsf{GAMBIT}$. We perform a global analysis of effective field theory (EFT) operators describing the interactions between a gauge-singlet Dirac fermion and the Standard Model quarks, the gluons and the photon. In this bottom-up approach, we simultaneously vary the coefficients of 14 such operators up to dimension 7, along with the DM mass, the scale of new physics and several nuisance parameters. Our likelihood functions include the latest data…
