Search Publications

Primordial Black Holes in Scalar Field Inflation Coupled to the Gauss–Bonnet Term with Fractional Power-law Potentials
DOI: 10.3847/1538-4357/ad293f Bibcode: 2024ApJ...965...11A

Ashrafzadeh, Ali; Karami, Kayoomars

In this study, we investigate the formation of primordial black holes (PBHs) in a scalar field inflationary model coupled to the Gauss–Bonnet term with fractional power-law potentials. The coupling function enhances the curvature perturbations, then results in the generation of PBHs and detectable secondary gravitational waves (GWs). We identify t…

2024 The Astrophysical Journal
INTEGRAL 13
Resurrecting Hitomi for Decaying Dark Matter and Forecasting Leading Sensitivity for XRISM
DOI: 10.1103/PhysRevLett.132.211002 Bibcode: 2024PhRvL.132u1002D

Safdi, Benjamin R.; Dessert, Christopher; Rodd, Nicholas L. +1 more

The Hitomi x-ray satellite mission carried unique high-resolution spectrometers that were set to revolutionize the search for sterile neutrino dark matter (DM) by looking for narrow x-ray lines arising from DM decays. Unfortunately, the satellite was lost shortly after launch, and to date the only analysis using Hitomi for DM decay used data taken…

2024 Physical Review Letters
Hitomi XMM-Newton 13
What if GW190425 did not produce a black hole promptly?
DOI: 10.1093/mnras/stae400 Bibcode: 2024MNRAS.528.5836R

Murase, Kohta; Radice, David; Ricigliano, Giacomo +3 more

It is widely believed that the binary neutron star merger GW190425 produced a black hole promptly upon merger. Motivated by the potential association with the fast radio burst FRB 20190425A, which took place 2.5 h after the merger, we revisit the question of the outcome of GW190425 by means of numerical relativity simulations. We show that current…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 13
A census of new globular clusters in the Galactic bulge
DOI: 10.1051/0004-6361/202346377 Bibcode: 2024A&A...687A.201B

Bica, E.; Barbuy, B.; Ortolani, S. +1 more

Context. The number of known globular clusters in the Galactic bulge has been increasing steadily thanks to different new surveys. Aims. The aim of this study is to provide a census of the newly revealed globular clusters in the Galactic bulge, and analyze their characteristics. Methods. In recent years, many globular clusters have been discovered…

2024 Astronomy and Astrophysics
Gaia eHST 13
The FLAMINGO simulation view of cluster progenitors observed in the epoch of reionization with JWST
DOI: 10.1093/mnras/stae1790 Bibcode: 2024MNRAS.532.4551L

Maiolino, Roberto; Tacchella, Sandro; Helton, Jakob M. +4 more

Motivated by the recent JWST discovery of galaxy overdensities during the Epoch of Reionzation, we examine the physical properties of high-z protoclusters and their evolution using the Full-hydro Large-scale structure simulations with All-sky Mapping for the Interpretation of Next Generation Observations (FLAMINGO) simulation suite. We investigate…

2024 Monthly Notices of the Royal Astronomical Society
JWST 13
Galaxy mergers in UNIONS - I. A simulation-driven hybrid deep learning ensemble for pure galaxy merger classification
DOI: 10.1093/mnras/stae1885 Bibcode: 2024MNRAS.533.2547F

Ellison, Sara L.; Gwyn, Stephen D. J.; Ferreira, Leonardo +7 more

Merging and interactions can radically transform galaxies. However, identifying these events based solely on structure is challenging as the status of observed mergers is not easily accessible. Fortunately, cosmological simulations are now able to produce more realistic galaxy morphologies, allowing us to directly trace galaxy transformation throu…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 13
Bioverse: The Habitable Zone Inner Edge Discontinuity as an Imprint of Runaway Greenhouse Climates on Exoplanet Demographics
DOI: 10.3847/PSJ/acf57f Bibcode: 2024PSJ.....5....3S

Apai, Dániel; Schlecker, Martin; Hardegree-Ullman, Kevin K. +3 more

Long-term magma ocean phases on rocky exoplanets orbiting closer to their star than the runaway greenhouse threshold-the inner edge of the classical habitable zone-may offer insights into the physical and chemical processes that distinguish potentially habitable worlds from others. The thermal stratification of runaway planets is expected to signi…

2024 The Planetary Science Journal
Gaia 13
JWST discovers an AGN ionization cone but only weak radiatively driven feedback in a powerful z ≈ 3.5 radio-loud AGN
DOI: 10.1051/0004-6361/202348531 Bibcode: 2024A&A...683A.169W

Lehnert, Matthew D.; Zakamska, Nadia L.; Stern, Daniel +7 more

We present the first results from a JWST program studying the role played by powerful radio jets in the evolution of the most massive galaxies at the onset of cosmic noon. Using NIRSpec integral field spectroscopy, we detected 24 rest-frame optical emission lines from the z = 3.5892 radio galaxy 4C+19.71, which contains one of the most energetic r…

2024 Astronomy and Astrophysics
Gaia eHST JWST 13
The Galactic bulge exploration. I. The period-absolute magnitude-metallicity relations for RR Lyrae stars for GBP, V, G, GRP, I, J, H, and Ks passbands using Gaia DR3 parallaxes
DOI: 10.1051/0004-6361/202347338 Bibcode: 2024A&A...684A.176P

Prudil, Z.; Kunder, A.; Koch-Hansen, A. J. +1 more

We present a new set of period-absolute magnitude-metallicity (PMZ) relations for single-mode RR Lyrae stars calibrated for the optical GBP, V, G, GRP, near-infrared I, J, H, and Ks passbands. We compiled a large dataset (over 100 objects) of fundamental and first-overtone RR Lyrae pulsators consisting of mean inte…

2024 Astronomy and Astrophysics
Gaia 13
The first degree-scale starlight-polarization-based tomography map of the magnetized interstellar medium
DOI: 10.1051/0004-6361/202349015 Bibcode: 2024A&A...684A.162P

Eriksen, H. K.; Ghosh, T.; Gjerløw, E. +21 more

We present the first degree-scale tomography map of the dusty magnetized interstellar medium (ISM) from stellar polarimetry and distance measurements. We used the RoboPol polarimeter at Skinakas Observatory to conduct a survey of the polarization of starlight in a region of the sky of about four square degrees. We propose a Bayesian method to deco…

2024 Astronomy and Astrophysics
Gaia 13