Search Publications

Flares, Rotation, and Planets of the AU Mic System from TESS Observations
DOI: 10.3847/1538-3881/ac23ca Bibcode: 2022AJ....163..147G

Barclay, Thomas; Latham, David W.; Wittenmyer, Robert A. +20 more

AU Mic is a young (~24 Myr), pre-main-sequence M dwarf star that was observed in the first month of science observations of the Transiting Exoplanet Survey Satellite (TESS) and reobserved 2 years later. This target has photometric variability from a variety of sources that is readily apparent in the TESS light curves; spots induce modulation in th…

2022 The Astronomical Journal
Gaia eHST 58
Optical superluminal motion measurement in the neutron-star merger GW170817
DOI: 10.1038/s41586-022-05145-7 Bibcode: 2022Natur.610..273M

Anderson, Jay; Lu, Wenbin; Mooley, Kunal P.

The afterglow of the binary neutron-star merger GW1708171 gave evidence for a structured relativistic jet2-6 and a link3,7,8 between such mergers and short gamma-ray bursts. Superluminal motion, found using radio very long baseline interferometry3 (VLBI), together with the afterglow light curve provided …

2022 Nature
Gaia eHST 58
No Such Thing as a Simple Flare: Substructure and Quasi-periodic Pulsations Observed in a Statistical Sample of 20 s Cadence TESS Flares
DOI: 10.3847/1538-4357/ac426e Bibcode: 2022ApJ...926..204H

MacGregor, Meredith A.; Howard, Ward S.

A 20 s cadence Transiting Exoplanet Survey Satellite monitoring campaign of 226 low-mass flare stars during Cycle 3 recorded 3792 stellar flares of ≥1032 erg. We explore the time-resolved emission and substructure in 440 of the largest flares observed at high signal-to-noise, 97% of which released energies of ≥1033 erg. We di…

2022 The Astrophysical Journal
Gaia 58
Do quasar X-ray and UV flux measurements provide a useful test of cosmological models?
DOI: 10.1093/mnras/stab3678 Bibcode: 2022MNRAS.510.2753K

Khadka, Narayan; Ratra, Bharat

The recent compilation of quasar (QSO) X-ray and ultraviolet (UV) flux measurements include QSOs that appear to not be standardizable via the X-ray luminosity and UV luminosity (LX-LUV) relation and so should not be used to constrain cosmological model parameters. Here, we show that the largest of seven sub-samples in this co…

2022 Monthly Notices of the Royal Astronomical Society
XMM-Newton 58
Early Results from GLASS-JWST. VII. Evidence for Lensed, Gravitationally Bound Protoglobular Clusters at z = 4 in the Hubble Frontier Field A2744
DOI: 10.3847/2041-8213/ac8c2d Bibcode: 2022ApJ...940L..53V

Henry, Alaina; Zanella, A.; Vulcani, B. +29 more

We investigate the blue and optical rest-frame sizes (λ ≃ 2300-4000 Å) of three compact star-forming regions in a galaxy at z = 4 strongly lensed (×30, ×45, and ×100) by the Hubble Frontier Field galaxy cluster A2744 using GLASS-ERS James Webb Space Telescope (JWST)/NIRISS imaging at 1.15 µm, 1.50 µm, and 2.0 µm with a point-spre…

2022 The Astrophysical Journal
eHST JWST 57
The observed multiplicity properties of B-type stars in the Galactic young open cluster NGC 6231
DOI: 10.1051/0004-6361/202141037 Bibcode: 2022A&A...658A..69B

Evans, C. J.; Sana, H.; Mahy, L. +3 more

Context. It is well known that massive O stars are frequently (if not always) found in binary or higher-order multiple systems, but this fact has been less robustly investigated for the lower mass range of the massive stars, represented by B-type stars. Obtaining the binary fraction and orbital parameter distributions of B-type stars is crucial to…

2022 Astronomy and Astrophysics
Gaia 57
The DECam Local Volume Exploration Survey Data Release 2
DOI: 10.3847/1538-4365/ac78eb Bibcode: 2022ApJS..261...38D

Bacon, D.; Bechtol, K.; Smith, M. +125 more

We present the second public data release (DR2) from the DECam Local Volume Exploration survey (DELVE). DELVE DR2 combines new DECam observations with archival DECam data from the Dark Energy Survey, the DECam Legacy Survey, and other DECam community programs. DELVE DR2 consists of ~160,000 exposures that cover >21,000 deg2 of the hi…

2022 The Astrophysical Journal Supplement Series
Gaia 57
Identifying quiescent compact objects in massive Galactic single-lined spectroscopic binaries
DOI: 10.1051/0004-6361/202243147 Bibcode: 2022A&A...664A.159M

Shenar, T.; Sana, H.; Hawcroft, C. +13 more

Context. The quest to detect dormant stellar-mass black holes (BHs) in massive binaries (i.e. OB+BH systems) is challenging; only a few candidates have been claimed to date, all of which must still be confirmed.
Aims: To search for these rare objects, we study 32 Galactic O-type stars that were reported as single-lined spectroscopic binaries …

2022 Astronomy and Astrophysics
Gaia IUE 57
The Warm Neptune GJ 3470b Has a Polar Orbit
DOI: 10.3847/2041-8213/ac6e3c Bibcode: 2022ApJ...931L..15S

Cochran, William D.; Endl, Michael; Mahadevan, Suvrath +34 more

The warm Neptune GJ 3470b transits a nearby (d = 29 pc) bright slowly rotating M1.5-dwarf star. Using spectroscopic observations during two transits with the newly commissioned NEID spectrometer on the WIYN 3.5 m Telescope at Kitt Peak Observatory, we model the classical Rossiter-McLaughlin effect, yielding a sky-projected obliquity of $\lambda ={…

2022 The Astrophysical Journal
Gaia 57
An Improved Calibration of the Wavelength Dependence of Metallicity on the Cepheid Leavitt Law
DOI: 10.3847/1538-4357/ac97e2 Bibcode: 2022ApJ...939...89B

Riess, Adam G.; Breuval, Louise; Anderson, Richard I. +2 more

The Cepheid period-luminosity (PL) relation (or Leavitt law) has served as the first rung of the most widely used extragalactic distance ladder and is central to the determination of the local value of the Hubble constant (H 0). We investigate the influence of metallicity on Cepheid brightness, a term that significantly improves the ove…

2022 The Astrophysical Journal
Gaia eHST 57