First Analysis of Jupiter in Gamma Rays and a New Search for Dark Matter

Abstract

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 ∼ 10 −9 GeV cm −2 s −1 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 10 −41 cm 2 , 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.

Evaporation of dark matter from celestial bodies

“…Finally, note that some recent works did not follow these arguments and incorrectly estimated the DM evaporation mass [30,32,68,75,94]. In Ref.…”

“…The DM evaporation mass has been computed at different levels of detail for the case of the Sun [2, 3, 5-7, 10, 19, 21, 64-67], but has been less studied for other celestial bodies. Some examples, however, are the calculations for the Earth [18,19,23,31], the Moon [31], Mars [30], giant planets [32,68], brown dwarfs [32,33], main-sequence stars [33,69], horizontal-branch stars [49,70], and neutron stars [71,72].…”

“…Recently, searches of effects of the accretion of sub-GeV DM particles in giant planets and brown dwarfs have been proposed [32,68,75]. The ideas rely on estimates of the DM evaporation mass for those objects as low as a few MeV, based on their relatively large size and cool temperatures.…”

Constraining Time Dependent Dark Matter Signals from the Sun

“…Alternatively, DM may annihilate into new long-lived mediators which can escape the Sun and decay into SM particles outside the Sun [24][25][26][27][28][29]. It is also shown that Jupiter can be a viable DM target especially for sub-GeV DM owing to its cooler core temperature compared to the Sun [30]. These scenarios are realized in the context of secluded DM models.…”

Scattering searches for dark matter in subhalos: neutron stars, cosmic rays, and old rocks

“…For instance, if DM thermalizes slowly with the NS, annihilations may turn on late, so that there are two reheating periods in our "infrequent encounter" regime. DM annihilations following capture of subhalo DM could also produce detectable signals in a variety of celestial bodies [77,[111][112][113]. While we have focused on DM-nucleon scattering, some of our approaches also apply to DM that scatters on leptons.…”