Search Publications
Preliminary Discussion on the Current Sheet
Zhang, Jun; Ding, Tao; Fang, Yuan +1 more
The current sheet is a characteristic structure of magnetic energy dissipation during the magnetic reconnection process. So far, the width and depth of the current sheet are still indefinite. Here we investigate 64 current sheets observed by four telescopes from 1999 to 2022, and all of them have been well identified in the previous literature. In…
COOL-LAMPS. VI. Lens Model and New Constraints on the Properties of COOL J1241+2219, a Bright z = 5 Lyman Break Galaxy and its z = 1 Cluster Lens
Mahler, Guillaume; Bayliss, Matthew; Sharon, Keren +20 more
We present a strong lensing analysis of COOL J1241+2219, the brightest known gravitationally lensed galaxy at z ≥ 5, based on new multiband Hubble Space Telescope (HST) imaging data. The lensed galaxy has a redshift of z = 5.043, placing it shortly after the end of the "Epoch of Reionization," and an AB magnitude z AB = 20.47 mag (Khull…
Connections between Planetary Populations and Chemical Characteristics of Their Host Stars
Beers, Timothy C.; Lee, Young Sun; Kim, Young Kwang +3 more
Chemical anomalies in planet-hosting stars (PHSs) are studied in order to assess how the planetary nature and multiplicity affect the atmospheric chemical abundances of their host stars. We employ APOGEE DR17 to select thin-disk stars of the Milky Way, and crossmatch them with the Kepler Input Catalog to identify confirmed PHSs, which results in 2…
ϵ Sagittarii: An Extreme Rapid Rotator with a Decretion Disk
Lewis, Fiona; Bailey, Jeremy; Cotton, Daniel V. +3 more
We report high-precision, multiwavelength linear-polarization observations of the bright B9 (or A0) star ϵ Sagittarii. The polarization shows the distinctive wavelength dependence expected for a rapidly rotating star. Analysis of the polarization data reveals an angular rotation rate ω (=Ω/Ωcrit) of 0.995 or greater, the highest yet mea…
A JWST Project on 47 Tucanae: NIRSpec Spectroscopy of Multiple Populations among M Dwarfs
Milone, A. P.; Cordoni, G.; Marino, A. F. +12 more
We present the first spectroscopic estimates of the chemical abundance of M dwarf stars in a globular cluster (GC), namely 47 Tucanae. By exploiting NIRSpec on board the James Webb Space Telescope, we gathered low-resolution spectra for 28 stars with masses in the range ∼0.4–0.5 M ⊙. The spectra are strongly affected by the H2
The Carousel Lens: A Well-modeled Strong Lens with Multiple Sources Spectroscopically Confirmed by VLT/MUSE
Kacprzak, Glenn G.; Glazebrook, Karl; Schlegel, David J. +12 more
Over the past few years alone, the lensing community has discovered thousands of strong lens candidates, and spectroscopically confirmed hundreds of them. In this time of abundance, it becomes pragmatic to focus our time and resources on the few extraordinary systems, in order to most efficiently study the Universe. In this paper, we present such …
JWST MIRI Imager Observations of Supernova SN 1987A
Fox, O. D.; Blommaert, J. A. D. L.; Larsson, J. +31 more
There exist very few mid-infrared (IR) observations of supernovae (SNe) in general. Therefore, SN 1987A, the closest visible SN in 400 yr, gives us the opportunity to explore the mid-IR properties of SNe, the dust in their ejecta, and the surrounding medium and to witness the birth of an SN remnant (SNR). The James Webb Space Telescope, with its h…
The Mass Dependence of Hα Emission and Stellar Spindown for Fully Convective M Dwarfs
Latham, David W.; Berlind, Perry; Calkins, Michael L. +4 more
Fully convective M dwarfs typically remain rapidly rotating and magnetically active for billions of years, followed by an abrupt and mass-dependent transition to slow rotation and quiescence. A robust understanding of this process is complicated by difficulties in estimating M dwarf ages and potential dependencies on other variables such as birth …
The Orbit of NGC 5907 ULX-1
Wolter, Anna; Pintore, Fabio; Mereghetti, Sandro +13 more
We report on the orbit of the binary system powering the most extreme ultraluminous X-ray pulsar known to date: NGC 5907 ULX-1 (hereafter ULX1). ULX1 has been the target of a substantial multi-instrument campaign, mainly in the X-ray band, but no clear counterparts are known in other bands. Although ULX1 is highly variable and pulsations can be tr…
The "Magnificent Seven" X-Ray Isolated Neutron Stars Revisited. I. Improved Timing Solutions and Pulse Profile Analysis
Bogdanov, Slavko; Ho, Wynn C. G.
We present the first systematic X-ray pulse timing analysis of the six members of the so-called "Magnificent Seven" nearby thermally emitting isolated neutron stars (XINS) with detected pulsations. Using the extensive collection of archival XMM-Newton, Chandra, and NICER observations spanning over two decades, we obtain the first firm measurement …