Search Publications
Weak equivalence principle and nonrelativistic limit of general dispersion relations
Hohmann, Manuel; Pfeifer, Christian; Wagner, Fabian
We study the weak equivalence principle in the context of modified dispersion relations, a prevalent approach to quantum gravity phenomenology. We find that generic modified dispersion relations violate the weak equivalence principle. The acceleration in general depends on the mass of the test body, unless the Hamiltonian is either 2-homogeneous i…
Dark matter limits from the tip of the red giant branch of globular clusters
Hong, Haozhi; Vincent, Aaron C.
Capture and annihilation of weakly interacting massive particle (WIMP)-like dark matter in red giant stars can lead to faster-than-expected ignition of the helium core, and thus a lower tip of the red giant branch (TRGB) luminosity. We use Gaia data to place constraints on the dark matter-nucleon cross section using 22 globular clusters with measu…
Constraining the low-energy cosmic ray flux in the center molecular zone from MeV nuclear deexcitation line observations
Liu, Bing; Yang, Ruizhi
Low-energy cosmic rays (LECRs) dominate the ionization in dense regions of molecular clouds in which other ionizers such as UV or x-ray photons are effectively shielded. Thus, it was argued that the high ionization rate at the central molecular zone (CMZ) of our Galaxy is mainly caused by LECRs. However, the required LECR flux is orders of magnitu…
No evidence for gamma-ray emission from the Sagittarius dwarf spheroidal galaxy
Calore, Francesca; Eckner, Christopher; Manconi, Silvia
More than a decade ago, the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope unveiled the existence of two gigantic gamma-ray lobes known as the Fermi bubbles. While their origin is still unknown, various studies identified intricate spectral and morphological structures within the bubbles. One peculiar region, the cocoon, has recen…
Cosmological constraints from type-I radio-loud quasars
Chang, N.; Huang, L.; Tu, Z. Y. +3 more
We obtain a sample of 1192 type-I quasars with the UV-optical, radio, and x-ray waveband coverage, which combined with the data from Huang and Chang [Mon. Not. R. Astron. Soc. 515, 1358 (2022), 10.1093/mnras/stac1451] and other matching objects of SDSS-DR16 with FIRST, XMM-Newton, and Chandra Source Catalog, and a sample of 407 flat-spectrum radio…
Precise measurement of pion-bump structure using future MeV gamma-ray detectors
Liu, Jiahao; Liu, Bing; Yang, Ruizhi
The pion-bump structure in the
Constraints on the parameters of keV-scale mass annihilating dark matter obtained with SRG/ART-XC observations
Burenin, R. A.; Krivonos, R. A.; Zakharov, E. I. +2 more
In this paper we present new constraints on the velocity-independent cross section of keV-scale mass annihilating dark matter particles obtained with SRG/ART-XC after 4 full-sky surveys. These constraints are derived from observations of the Milky Way Halo, 33 Local Group spheroidal dwarf (dSph) galaxies and separately for the dSph galaxy Ursa Maj…