Search Publications
Primordial Black Holes in Scalar Field Inflation Coupled to the Gauss–Bonnet Term with Fractional Power-law Potentials
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…
The Next Generation Deep Extragalactic Exploratory Public Near-infrared Slitless Survey Epoch 1 (NGDEEP-NISS1): Extragalactic Star-formation and Active Galactic Nuclei at 0.5 < z < 3.6
Papovich, Casey; Finkelstein, Steven L.; Pérez-González, Pablo G. +48 more
The Next Generation Deep Extragalactic Exploratory Public (NGDEEP) survey program was designed specifically to include Near Infrared Slitless Spectroscopic observations (NGDEEP-NISS) to detect multiple emission lines in as many galaxies as possible and across a wide redshift range using the Near Infrared Imager and Slitless Spectrograph. We presen…
NICER Discovery that SRGA J144459.2–604207 Is an Accreting Millisecond X-Ray Pulsar
Chakrabarty, Deepto; Ray, Paul S.; Wolff, Michael T. +17 more
We present the discovery, with the Neutron Star Interior Composition Explorer (NICER), that SRGA J144459.2‑604207 is a 447.9 Hz accreting millisecond X-ray pulsar (AMXP), which underwent a 4 week long outburst starting on 2024 February 15. The AMXP resides in a 5.22 hr binary, orbiting a low-mass companion donor with M d > 0.1 M
Spectral Calculations of 3D Radiation Magnetohydrodynamic Simulations of Super-Eddington Accretion onto a Stellar-mass Black Hole
Middleton, Matthew J.; Mills, Brianna S.; Davis, Shane W. +1 more
We use the Athena++ Monte Carlo (MC) radiation transfer module to postprocess simulation snapshots from nonrelativistic Athena++ radiation magnetohydrodynamic (RMHD) simulations. These simulations were run using a gray (frequency-integrated) approach but were also restarted and ran with a multigroup approach that accounts for Compton scattering wi…
CEERS: 7.7 µm PAH Star Formation Rate Calibration with JWST MIRI
Papovich, Casey; Yang, Guang; Finkelstein, Steven L. +33 more
We test the relationship between UV-derived star formation rates (SFRs) and the 7.7 µm polycyclic aromatic hydrocarbon luminosities from the integrated emission of galaxies at z ∼ 0–2. We utilize multiband photometry covering 0.2–160 µm from the Hubble Space Telescope, CFHT, JWST, Spitzer, and Herschel for galaxies in the Cosmic Evolut…
On the Pair-instability Supernova Origin of J1010+2358
Aguado, David S.; Lucchesi, Romain; Amarsi, Anish M. +4 more
The first (Population III) stars formed only out of H and He and were likely more massive than present-day stars. Massive Population III stars in the range 140–260 M ⊙ are predicted to end their lives as pair-instability supernovae (PISNe), enriching the environment with a unique abundance pattern, with high ratios of odd to even elemen…
JWST Observations of Starbursts: Polycyclic Aromatic Hydrocarbon Emission at the Base of the M82 Galactic Wind
Boogaard, Leindert A.; Meier, David S.; Böker, Torsten +37 more
We present new observations of the central 1 kpc of the M82 starburst obtained with the James Webb Space Telescope near-infrared camera instrument at a resolution θ ∼ 0.″05–0.″1 (∼1–2 pc). The data comprises images in three mostly continuum filters (F140M, F250M, and F360M), and filters that contain [Fe II] (F164N), H2 v = 1 → 0 (F212N)…
PASSAGES: The Wide-ranging, Extreme Intrinsic Properties of Planck-selected, Lensed Dusty Star-forming Galaxies
Frye, Brenda L.; Yun, Min S.; Wang, Q. Daniel +11 more
The PASSAGES (Planck All-Sky Survey to Analyze Gravitationally-lensed Extreme Starbursts) collaboration has recently defined a sample of 30 gravitationally lensed dusty star-forming galaxies (DSFGs). These rare, submillimeter-selected objects enable high-resolution views of the most extreme sites of star formation in galaxies at cosmic noon. Here,…
A JWST Project on 47 Tucanae. Overview, Photometry, and Early Spectroscopic Results of M Dwarfs and Observations of Brown Dwarfs
Milone, A. P.; Cordoni, G.; Marino, A. F. +14 more
James Webb Space Telescope (JWST) observations have been demonstrated to be efficient in detecting multiple stellar populations in globular clusters (GCs) in the low-mass regime of M dwarfs. We present an overview, and first results, of different projects that can be explored by using the JWST observations gathered under program GO2560 for 47 Tuca…
Many Roads Lead to Lithium: Formation Pathways For Lithium-rich Red Giants
Bedell, Megan; Casey, Andrew R.; Buder, Sven +8 more
Stellar models predict that lithium (Li) inside a star is destroyed during the first dredge-up phase, yet 1.2% of red giant stars are Li-rich. We aim to uncover possible origins of this population, by analyzing 1099 Li-rich giants (A(Li) ≥ 1.5) in GALAH DR3. To expose peculiar traits of Li-rich stars, we construct a reference sample of Li-normal (…