44 research outputs found
Floating Dark Matter in Celestial Bodies
Dark matter (DM) can be captured in celestial bodies after scattering and
losing sufficient energy to become gravitationally bound. We derive a general
framework that describes the current DM distribution inside celestial objects,
which self-consistently includes the effects of concentration diffusion,
thermal diffusion, gravity, and capture accumulation. For DM with sufficient
interactions, we show that a significant DM population can thermalize and sit
towards the celestial-body surface. This floating distribution allows for new
phenomenology for DM searches in a wide range of celestial bodies, including
the Sun, Earth, Jupiter, Brown Dwarfs, and Exoplanets.Comment: 20 pages, 6 figures, 100000000000000+ dark matter particles per cm^3
at Earth's surfac
Dark Matter Capture in Celestial Objects: Treatment Across Kinematic and Interaction Regimes
Signatures of dark matter in celestial objects have become of increasing
interest due to their powerful detection prospects. To test any of these
signatures, the fundamental quantity needed is the rate in which dark matter is
captured by celestial objects. Depending on whether dark matter is light,
heavy, or comparable in mass to the celestial-body scattering targets, there
are different considerations when calculating the capture rate. Furthermore, if
dark matter has strong or weak interactions, the physical behaviour important
for capture varies. Using both analytic approximations and simulations, we
demonstrate how to treat dark matter capture in a range of celestial objects
for arbitrary dark matter mass and interaction strength. We release our
calculation framework as a public package available in both Python and
Mathematica versions, called Asteria.Comment: 32 pages, 11 figures, for the Asteria package, see
https://zenodo.org/record/815011
First Analysis of Jupiter in Gamma Rays and a New Search for Dark Matter
We present the first dedicated gamma-ray analysis of Jupiter, using 12 years
of data from the Fermi Telescope. We find no robust evidence of gamma-ray
emission, and set upper limits of GeV cms on the
Jovian gamma-ray flux. We point out that Jupiter is an advantageous dark matter
(DM) target due to its large surface area (compared to other solar system
planets), and cool core temperature (compared to the Sun). These properties
allow Jupiter to both capture and retain lighter DM, providing a complementary
probe of sub-GeV DM. Our analysis focuses on the annihilation of sub-GeV DM to
long-lived particles, which can escape the Jovian surface and decay into gamma
rays. In this regime, we constrain DM-proton scattering cross-sections as low
as cm, which is up to ten orders of magnitude more sensitive
than direct detection, and subject to fewer astrophysical uncertainties than
other limits in this parameter space. Our work motivates follow-up studies with
upcoming MeV telescopes such as AMEGO and e-ASTROGAM.Comment: 13 pages, 5 figure
Leptophilic Dark Matter with interactions
We consider a scenario where dark matter (DM) interacts exclusively with
Standard Model (SM) leptons at tree level. Due to the absence of tree-level
couplings to quarks, the constraints on leptophilic dark matter arising from
direct detection and hadron collider experiments are weaker than those for a
generic WIMP. We study a simple model in which interactions of DM with SM
leptons are mediated by a leptophilic boson, and determine constraints on
this scenario arising from relic density, direct detection, and other
experiments. We then determine current LHC limits and project the future
discovery reach. We show that, despite the absence of direct interactions with
quarks, this scenario can be strongly constrained.Comment: 12 pages, 15 figure