相关论文: $J$-factors for Velocity-dependent Dark Matter
In the cold dark matter scenario, galactic dark matter halos are populated with a large number of smaller subhalos. Previous work has shown that dark matter annihilations in subhalos can generate a distinctive, non-Poisson signal in the…
Dark matter annihilation in dwarf spheroidal (dSph) galaxies near the Milky Way has the potential to produce a detectable signature in gamma-rays. The amplitude of this signal depends on the dark matter density in a dSph, the dark matter…
Gamma-ray observations have long been used to constrain the properties of dark matter (DM), with a strong focus on weakly interacting massive particles annihilating through velocity-independent processes. However, in the absence of…
The expected gamma-ray flux coming from dark matter annihilation in dwarf spheroidal (dSph) galaxies depends on the so-called `J-factor', the integral of the squared dark matter density along the line-of-sight. We examine the degree to…
Line-of-sight integrals of the squared density, commonly called the J-factor, are essential for inferring dark matter annihilation signals. The J-factors of dark matter-dominated dwarf spheroidal satellite galaxies (dSphs) have typically…
We present the first public code for semi-analytical calculation of the gamma-ray flux astrophysical J-factor from dark matter annihilation/decay in the Galaxy, including dark matter substructures. The core of the code is the calculation of…
A recent analysis of pulsar timing data has reported evidence for a massive ($\sim 6 \times 10^7 M_{\odot}$) dark matter subhalo located only $\sim 0.8$ kpc from Earth. This candidate implies an exceptionally large $J$-factor of $\sim…
Dwarf spheroidal galaxies are among the most promising targets for indirect dark matter (DM) searches in $\gamma$-rays. The $\gamma$-ray flux from DM annihilation in a dwarf spheroidal galaxy is proportional to the $J$-factor of the source.…
Searching for gamma rays from dwarf spheroidal galaxies (dSphs) is a promising approach to detect dark matter (DM) due to the high DM densities and low baryon components in dSphs. The Fermi-LAT observations from dSphs have set stringent…
We use the suite of Milky Way-like galaxies in the Auriga simulations to determine the contribution to annihilation radiation from dark matter subhalos in three velocity-dependent dark matter annihilation models: Sommerfeld, p-wave, and…
In a large region of the supersymmetry parameter space, the annihilation cross section for neutralino dark matter is strongly dependent on the relative velocity of the incoming particles. We explore the consequences of this velocity…
We derive cosmological constraints on the annihilation cross section of dark matter with velocity-dependent structure, motivated by annihilating dark matter models through Sommerfeld or Breit-Wigner enhancement mechanisms. In models with…
We use FIRE-2 zoom cosmological simulations of Milky Way size galaxy halos to characterize the shape of the J-factor emission signal on the sky. We find that, at a fixed dJ/d{\Omega} contour,the shape is well-fit by an ellipse, with…
Dark matter density profiles based upon Lambda-CDM cosmology motivate an ansatz velocity distribution function with fewer high velocity particles than the Maxwell-Boltzmann distribution or proposed variants. The high velocity tail of the…
In models of dark matter (DM) with Sommerfeld-enhanced annihilation, where the annihilation rate scales as the inverse velocity, N-body simulations of DM structure formation suggest that the local annihilation signal may be dominated by…
Cosmological $N$-body simulations show that Milky Way-sized galaxies harbor a population of unmerged dark matter subhalos. These subhalos could shine in gamma-rays and be eventually detected in gamma-ray surveys as unidentified sources. We…
We consider gamma-ray signals of dark matter annihilation in extragalactic halos in the case where dark matter annihilates from a $p$-wave or $d$-wave state. In these scenarios, signals from extragalactic halos are enhanced relative to…
We study the indirect detection of dark matter when the local dark matter velocity distribution depends upon position, as expected for the Milky Way and its dwarf spheroidal satellites, and the annihilation cross-section is not purely…
Utilizing data from the ELVIS and Via Lactea-II simulations, we characterize the local dark matter subhalo population, and use this information to refine the predictions for the gamma-ray fluxes arising from annihilating dark matter in this…
We use 413 weeks of publicly-available $\textit{Fermi}$ Pass 8 gamma-ray data, combined with recently-developed galaxy group catalogs, to search for evidence of dark matter annihilation in extragalactic halos. In our study, we use…