Search Publications
The Atacama Cosmology Telescope: Probing the baryon content of SDSS DR15 galaxies with the thermal and kinematic Sunyaev-Zel'dovich effects
Bond, J. R.; Calabrese, E.; Huffenberger, K. M. +51 more
We present measurements of the average thermal Sunyaev Zel'dovich (tSZ) effect from optically selected galaxy groups and clusters at high signal-to-noise (up to 12 σ ) and estimate their baryon content within a 2.1' radius aperture. Sources from the Sloan Digital Sky Survey Baryon Oscillation Spectroscopic Survey DR15 catalog overlap wi…
Sum of the masses of the Milky Way and M31: A likelihood-free inference approach
Lahav, Ofer; Hoffman, Yehuda; Whiteway, Lorne +3 more
We use density estimation likelihood-free inference, Λ cold dark matter simulations of ∼2 M galaxy pairs, and data from Gaia and the Hubble Space Telescope to infer the sum of the masses of the Milky Way and Andromeda (M31) galaxies, the two main components of the local group. This method overcomes most of the approximations of the traditional tim…
Gravitational wave detection with photometric surveys
Doré, Olivier; Wang, Yijun; Pardo, Kris +1 more
Gravitational wave (GW) detections have considerably enriched our understanding of the universe. To date, all GW events from individual sources have been found by interferometer-type detectors. In this paper, we study a GW detection technique based on astrometric solutions from photometric surveys and demonstrate that it offers a highly flexible f…
Do the observational data favor a local void?
Cai, Rong-Gen; Guo, Zong-Kuan; Ding, Jia-Feng +2 more
The increasing tension between the different local direct measurements of the Hubble expansion rate and that inferred from the cosmic microwave background observation by the Λ -cold-dark-matter model could be a smoking gun of new physics, if not caused by either observational systematics or local bias. We generalize previous investigation on the l…
Dark Higgs dark matter
Slone, Oren; Pospelov, Maxim; Mondino, Cristina +1 more
A new U (1 ) "dark" gauge group coupled to the Standard Model (SM) via the kinetic mixing portal provides a dark matter candidate in the form of the Higgs field, hd, responsible for generating the mass of the dark photon, γd. We show that the condition mhd≤mγd , together with smalln…
Scalar dark matter candidates revisited
Pradler, Josef; BÅ`hm, Céline; Chu, Xiaoyong +1 more
We revisit the possibility of light-scalar dark matter, in the MeV to GeV mass bracket and coupled to electrons through fermion or vector mediators, in light of significant experimental and observational advances that probe new physics below the GeV scale. We establish new limits from electron colliders and fixed-target beams and derive the streng…
Cosmological constraints on Hořava gravity revised in light of GW170817 and GRB170817A and the degeneracy with massive neutrinos
Frusciante, Noemi; Benetti, Micol
We revise the cosmological bounds on Hořava gravity, taking into account the stringent constraint on the speed of propagation of gravitational waves from GW170817 and GRB170817A. In light of this, we also investigate the degeneracy between massive neutrinos and Hořava gravity. We show that a luminal propagation of gravitational waves suppresses th…
Galactic bulge millisecond pulsars shining in x rays: A γ -ray perspective
Calore, Francesca; Petrucci, Pierre-Olivier; Clavel, Maïca +3 more
If the mysterious Fermi-LAT GeV γ -ray excess is due to an unresolved population of millisecond pulsars (MSP) in the Galactic bulge, one expects this very same population to shine in x rays. For the first time, we address the question of what is the sensitivity of current x-ray telescopes to an MSP population in the Galactic bulge. To this end, we…
Constraining the Konoplya-Rezzolla-Zhidenko deformation parameters. II. Limits from stellar-mass black hole x-ray data
Yu, Zhibo; Tripathi, Ashutosh; Abdikamalov, Askar B. +5 more
Astrophysical black holes are thought to be the Kerr black holes predicted by general relativity, but macroscopic deviations from the Kerr solution can be expected from a number of scenarios involving new physics. In Paper I, we studied the reflection features in NuSTAR and XMM-Newton spectra of the supermassive black hole at the center of the gal…
Radiation from matter-antimatter annihilation in the quark nugget model of dark matter
Flambaum, V. V.; Samsonov, I. B.
We revisit the properties of positron cloud in quark nugget (QN) model of dark matter (DM). In this model, dark matter particles are represented by compact composite objects composed of a large number of quarks or antiquarks with total baryon number B ∼1024. These particles have a very small number density in our galaxy which makes them…