Search Publications

Redshift evolution of the underlying type Ia supernova stretch distribution
DOI: 10.1051/0004-6361/202038447 Bibcode: 2021A&A...649A..74N

Smith, M.; Aldering, G.; Nordin, J. +7 more

The detailed nature of type Ia supernovae (SNe Ia) remains uncertain, and as survey statistics increase, the question of astrophysical systematic uncertainties arises, notably that of the evolution of SN Ia populations. We study the dependence on redshift of the SN Ia SALT2.4 light-curve stretch, which is a purely intrinsic SN property, to probe i…

2021 Astronomy and Astrophysics
eHST 62
Turbulent Generation of Magnetic Switchbacks in the Alfvénic Solar Wind
DOI: 10.3847/1538-4357/abfdbc Bibcode: 2021ApJ...915...52S

Cranmer, Steven R.; Shoda, Munehito; Chandran, Benjamin D. G.

One of the most important early results from the Parker Solar Probe (PSP) is the ubiquitous presence of magnetic switchbacks, whose origin is under debate. Using a three-dimensional direct numerical simulation of the equations of compressible magnetohydrodynamics from the corona to 40 solar radii, we investigate whether magnetic switchbacks emerge…

2021 The Astrophysical Journal
PROBA-2 62
Axion Emission Can Explain a New Hard X-Ray Excess from Nearby Isolated Neutron Stars
DOI: 10.1103/PhysRevLett.126.021102 Bibcode: 2021PhRvL.126b1102B

Buschmann, Malte; Safdi, Benjamin R.; Dessert, Christopher +1 more

Axions may be produced thermally inside the cores of neutron stars (NSs), escape the stars due to their feeble interactions with matter, and subsequently convert into x rays in the magnetic fields surrounding the stars. We show that a recently discovered excess of hard x-ray emission in the 2-8 keV energy range from the nearby magnificent seven is…

2021 Physical Review Letters
XMM-Newton 62
The search for failed supernovae with the Large Binocular Telescope: a new candidate and the failed SN fraction with 11 yr of data
DOI: 10.1093/mnras/stab2605 Bibcode: 2021MNRAS.508..516N

Kochanek, C. S.; Stanek, K. Z.; Adams, S. M. +5 more

We present updated results of the Large Binocular Telescope Search for Failed Supernovae. This search monitors luminous stars in 27 nearby galaxies with a current baseline of 11 yr of data. We re-discover the failed supernova (SN) candidate N6946-BH1 as well as a new candidate, M101-OC1. M101-OC1 is a blue supergiant that rapidly disappears in opt…

2021 Monthly Notices of the Royal Astronomical Society
eHST 62
The SPHERE infrared survey for exoplanets (SHINE). I. Sample definition and target characterization
DOI: 10.1051/0004-6361/202038806 Bibcode: 2021A&A...651A..70D

Fantinel, D.; Dominik, C.; Henning, Th. +106 more

Context. Large surveys with new-generation high-contrast imaging instruments are needed to derive the frequency and properties of exoplanet populations with separations from ~5 to 300 au. A careful assessment of the stellar properties is crucial for a proper understanding of when, where, and how frequently planets form, and how they evolve. The se…

2021 Astronomy and Astrophysics
Gaia 62
UV/Optical Disk Thermal Reverberation in Active Galactic Nuclei: An In-depth Study with an Analytic Prescription for Time-lag Spectra
DOI: 10.3847/1538-4357/abcb93 Bibcode: 2021ApJ...907...20K

Papadakis, I. E.; Dovčiak, M.; Karas, V. +2 more

Several active galactic nuclei show correlated variations in the UV/optical range, with time delays increasing at longer wavelengths. Thermal reprocessing of the X-rays illuminating the accretion disk has been proposed as a viable explanation. In this scenario, the variable X-ray flux irradiating the accretion disk is partially reflected in X-rays…

2021 The Astrophysical Journal
eHST 62
An unexpected high concentration for the dark substructure in the gravitational lens SDSSJ0946+1006
DOI: 10.1093/mnras/stab2247 Bibcode: 2021MNRAS.507.1662M

Gad-Nasr, Sophia; Minor, Quinn; Kaplinghat, Manoj +1 more

The presence of an invisible substructure has previously been detected in the gravitational lens galaxy SDSSJ0946+1006 through its perturbation of the lensed images. Using flexible models for the main halo and the subhalo perturbation, we demonstrate that the subhalo has an extraordinarily high central density and steep density slope. We robustly …

2021 Monthly Notices of the Royal Astronomical Society
eHST 62
Illuminating the Dark Side of Cosmic Star Formation Two Billion Years after the Big Bang
DOI: 10.3847/1538-4357/abd6e3 Bibcode: 2021ApJ...909...23T

Le Fèvre, Olivier; Faisst, Andreas; Cimatti, Andrea +5 more

How and when did galaxies form and assemble their stars and stellar mass? The answer to these questions, so crucial to astrophysics and cosmology, requires the full reconstruction of the so-called cosmic star formation rate density (SFRD), i.e., the evolution of the average star formation rate per unit volume of the universe. While the SFRD has be…

2021 The Astrophysical Journal
Herschel 62
WASP-107b's Density Is Even Lower: A Case Study for the Physics of Planetary Gas Envelope Accretion and Orbital Migration
DOI: 10.3847/1538-3881/abcd3c Bibcode: 2021AJ....161...70P

Gorjian, Varoujan; Lee, Eve J.; Angus, Ruth +21 more

With a mass in the Neptune regime and a radius of Jupiter, WASP-107b presents a challenge to planet formation theories. Meanwhile, the planet's low surface gravity and the star's brightness also make it one of the most favorable targets for atmospheric characterization. Here, we present the results of an extensive 4 yr Keck/HIRES radial-velocity (…

2021 The Astronomical Journal
Gaia 62
The Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER). I. Ultraviolet to Infrared Photometry of 22 Million Stars in M33
DOI: 10.3847/1538-4365/abdf4e Bibcode: 2021ApJS..253...53W

Bell, Eric F.; Lindberg, Christina W.; Williams, Benjamin F. +18 more

We present panchromatic resolved stellar photometry for 22 million stars in the Local Group dwarf spiral Triangulum (M33), derived from Hubble Space Telescope observations with the Advanced Camera for Surveys in the optical (F475W, F814W), and the Wide Field Camera 3 in the near-ultraviolet (F275W, F336W) and near-infrared (F110W, F160W) bands. Th…

2021 The Astrophysical Journal Supplement Series
Gaia Herschel eHST 62