利用AMS-02的精确测量，我们评估了宇宙射线反质子观测中的暗物质（DM）极限。我们适当地考虑到宇宙射线传播的不确定性拟合在同一时间DM和传播参数，并边缘化后者。我们发现一个显着的DM信号（~4.5西格玛）的DM质量接近80 GeV的指示，强子湮没截面接近的热值，西格玛v ~3e-26 cm 3 s-1。有趣的是，这个信号与DM对银河系中心伽马射线过剩的解释是一致的。信号的确认将需要对系统不确定性进行更准确的研究，即，反质子生产截面，太阳调制效应的建模。解释AMS-02的数据在强子DM湮灭的上限，我们得到强有力的约束，排除DM质量低于约50 GeV的热湮灭截面，在约150和500 GeV之间的范围内，即使是保守的传播方案。除了80 GeV的范围外，我们的极限是矮星系伽马射线观测极限的4倍。
英文摘要：
We evaluate dark matter (DM) limits from cosmic-ray antiproton observations using the recent precise AMS-02 measurements. We properly take into account cosmic-ray propagation uncertainties fitting at the same time DM and propagation parameters, and marginalizing over the latter. We find a significant (~4.5 sigma) indication of a DM signal for DM masses near 80 GeV, with a hadronic annihilation cross-section close to the thermal value, sigma v ~3e-26 cm3s-1. Intriguingly, this signal is compatible with the DM interpretation of the Galactic center gamma-ray excess. Confirmation of the signal will require a more accurate study of the systematic uncertainties, i.e., the antiproton production cross-section, and modelling of the solar modulation effect. Interpreting the AMS-02 data in terms of upper limits on hadronic DM annihilation, we obtain strong constraints excluding a thermal annihilation cross-section for DM masses below about 50 GeV and in the range between approximately 150 and 500 GeV, even for conservative propagation scenarios. Except for the range around 80 GeV, our limits are a factor 4 stronger than the limits from gamma-ray observations of dwarf galaxies.
Cosmic-ray antiprotons are a powerful tool for astroparticle physics. While the bulk of measured antiprotons is consistent with a secondary origin, the precise data of the AMS-02 experiment provides us with encouraging prospects to search for a subdominant primary component, e.g. from dark matter. In this brief review, we discuss recent limits on heavy dark matter as well as a tentative signal from annihilation of dark matter with a mass $\lesssim 100$ GeV. We emphasize the special role of systematic errors that can affect the signal. In particular, we discuss recent progress in the modeling o…
Based on 4 yr AMS-02 antiproton data, we present bounds on the dark matter (DM) annihilation cross section vs. mass for some representative final state channels. We use recent cosmic-ray propagation models, a realistic treatment of experimental and theoretical errors, and an updated calculation of input antiproton spectra based on a recent release of the PYTHIA code. We find that reported hints of a DM signal are statistically insignificant; an adequate treatment of errors is crucial for credible conclusions. Antiproton bounds on DM annihilation are among the most stringent ones, probing therm…
Cosmic-ray antiprotons are a remarkable diagnostic tool for the study of astroparticle physics' processes in our Galaxy. While the bulk of measured antiprotons is consistent with a secondary origin, several studies have found evidence for a subdominant primary component in the AMS-02 data. In this proceedings article, we revisit the excess considering systematic errors that could affect the signal. Of particular importance are unknown correlations in the AMS-02 systematic errors, the dominant of which are associated with the cross sections for cosmic-ray absorption in the detector. We compute …
Can we explain AMS-02 antiproton and positron excesses simultaneously by nearby supernovae without pulsars nor dark matter?
我们解释了过量的反质子分数最近报道的AMS-02实验考虑宇宙射线质子加速的本地超新星遗迹（SNR）和周围的致密云之间的碰撞。同样的“$pp$ -碰撞”提供了正确的子粒子比例，以同时在自然模型参数中拟合观察到的正电子过剩。这颗超新星的金属丰度比主要的宇宙射线源要低。电子的截止能量标志着超新星的年龄为$\sim 10^{5}$年，而反质子过剩可能会延伸到更高的能量。反质子和正电子通量都与我们在Fujita，Kohri，Yamasaki and Ioka（2009）中的预测完全一致。
Possible dark matter annihilation signal in the AMS-02 antiproton data
利用最新的AMS-02宇宙线反质子通量数据，寻找潜在的暗物质湮灭信号。关于传播、源注入和太阳调制的背景参数不是假定{ \it先验}的，而是基于从最近的B/C比和质子数据测量推断的结果。可能的暗物质信号被纳入模型自洽贝叶斯框架下。与只考虑天体物理背景的假设相比，我们发现暗物质信号更有利。暗物质粒子的静止质量为$\sim 20-80$ GeV，速度平均强子湮灭截面约为$(0.2-5)\times 10^{-26}$ cm $^{3}$ s $^{-1}$，与考虑银河系中心GeV过量和/或矮球状星系网状物2和杜鹃座III的弱GeV辐射所需的截面一致。对暗物质湮灭模型的严格约束也被设定在一个很宽的质量区域。
Several studies have pointed out an excess in the AMS-02 antiproton spectrum at rigidities of 10-20 GV. Its spectral properties were found to be consistent with a dark-matter particle of mass 50-100 GeV which annihilates hadronically at roughly the thermal rate. In this work, we reinvestigate the antiproton excess including all relevant sources of systematic errors. Most importantly, we perform a realistic estimate of the correlations in the AMS-02 systematic error which could potentially "fake" a dark-matter signal. The dominant systematics in the relevant rigidity range originate from uncert…
The antiproton flux measurements from AMS-02 offer valuable information about the nature of dark matter, but their interpretation is complicated by large uncertainties in the modeling of cosmic ray propagation. In this work we present a novel framework to efficiently marginalise over propagation uncertainties in order to obtain robust AMS-02 likelihoods for arbitrary dark matter models. The three central ingredients of this framework are: the neural emulator DarkRayNet, which provides highly flexible predictions of the antiproton flux; the likelihood calculator pbarlike, which performs the mar…
Revisiting predictions for cosmic-ray antinucleon fluxes from Galactic Dark Matter
Università di Torino（都灵大学）；Istituto Nazionale di Fisica Nucleare, Sezione di Torino（意大利国家核物理研究所都灵分部）；CERN（欧洲核子研究中心）；Université Grenoble-Alpes（格勒诺布尔阿尔卑斯大学）；LPSC（格勒诺布尔粒子物理实验室）
In this talk, we discuss the physics modeling of antiproton spectra arising from dark matter (DM) annihilation or decay in a model-independent manner. The modeling of antiproton spectra contains some intrinsic uncertainties related to QCD parton showers and hadronisation of baryons. We briefly assess the sources of these uncertainties and their impact on antiproton energy spectra for a few selected DM scenarios. The results are provided in tabulated form for future analyses.
