Search Publications
Probing the Origin of Changing-look Quasar Transitions with Chandra
Green, Paul J.; Anderson, Scott F.; Bieryla, Allyson +9 more
Extremely variable quasars can also show strong changes in broad-line emission strength and are known as changing-look quasars (CLQs). To study the CLQ transition mechanism, we present a pilot sample of CLQs with X-ray observations in both the bright and faint states. From a sample of quasars with bright-state archival SDSS spectra and (Chandra or…
The JWST PEARLS View of the El Gordo Galaxy Cluster and of the Structure It Magnifies
Grogin, Norman A.; Koekemoer, Anton M.; Pirzkal, Nor +41 more
The massive galaxy cluster El Gordo (z = 0.87) imprints multitudes of gravitationally lensed arcs onto James Webb Space Telescope Near-Infrared Camera (NIRCam) images. Eight bands of NIRCam imaging were obtained in the "Prime Extragalactic Areas for Reionization and Lensing Science" ("PEARLS") program. Point-spread function-matched photometry acro…
TOI-3235 b: A Transiting Giant Planet around an M4 Dwarf Star
Vanderburg, Andrew; Latham, David W.; Jordán, Andrés +34 more
We present the discovery of TOI-3235 b, a short-period Jupiter orbiting an M dwarf with a stellar mass close to the critical mass at which stars transition from partially to fully convective. TOI-3235 b was first identified as a candidate from TESS photometry and confirmed with radial velocities from ESPRESSO and ground-based photometry from HATSo…
The Role of High-frequency Transverse Oscillations in Coronal Heating
Van Doorsselaere, Tom; Lim, Daye; Berghmans, David +3 more
Transverse oscillations that do not show significant damping in solar coronal loops are found to be ubiquitous. Recently, the discovery of high-frequency transverse oscillations in small-scale loops has been accelerated by the Extreme Ultraviolet Imager on board Solar Orbiter. We perform a meta-analysis by considering the oscillation parameters re…
Magnetic Field Spectral Evolution in the Inner Heliosphere
Fedorov, A.; Horbury, T. S.; Louarn, P. +24 more
Parker Solar Probe and Solar Orbiter data are used to investigate the radial evolution of magnetic turbulence between 0.06 ≲ R ≲ 1 au. The spectrum is studied as a function of scale, normalized to the ion inertial scale d i . In the vicinity of the Sun, the inertial range is limited to a narrow range of scales and exhibits a power-law …
PHANGS-JWST First Results: Stellar-feedback-driven Excitation and Dissociation of Molecular Gas in the Starburst Ring of NGC 1365?
Bolatto, Alberto D.; Henshaw, Jonathan D.; Kruijssen, J. M. Diederik +36 more
We compare embedded young massive star clusters (YMCs) to (sub-)millimeter line observations tracing the excitation and dissociation of molecular gas in the starburst ring of NGC 1365. This galaxy hosts one of the strongest nuclear starbursts and richest populations of YMCs within 20 Mpc. Here we combine near-/mid-IR PHANGS-JWST imaging with new A…
The Bimodal Absorption System Imaging Campaign (BASIC). I. A Dual Population of Low-metallicity Absorbers at z < 1
Johnson, Sean D.; Tripp, Todd M.; Prochaska, J. Xavier +17 more
The bimodal absorption system imaging campaign (BASIC) aims to characterize the galaxy environments of a sample of 36 H I-selected partial Lyman limit systems (pLLSs) and Lyman limit systems (LLSs) in 23 QSO fields at z ≲ 1. These pLLSs/LLSs provide a unique sample of absorbers with unbiased and well-constrained metallicities, allowing us to explo…
A Hydrodynamic Study of the Escape of Metal Species and Excited Hydrogen from the Atmosphere of the Hot Jupiter WASP-121b
Lavvas, Panayotis; Koskinen, Tommi; Fossati, Luca +1 more
In the near-UV and optical transmission spectrum of the hot Jupiter WASP-121b, recent observations have detected strong absorption features of Mg, Fe, Ca, and Hα, extending outside of the planet's Roche lobe. Studying these atomic signatures can directly trace the escaping atmosphere and constrain the energy balance of the upper atmosphere. To und…
JWST Measurements of 13C, 18O, and 17O in the Atmosphere of Super-Jupiter VHS 1256 b
Zhang, Yapeng; Gandhi, Siddharth; de Regt, Sam +4 more
Isotope ratios have recently been measured in the atmospheres of directly imaged and transiting exoplanets from ground-based observations. The arrival of JWST allows us to characterize exoplanetary atmospheres in further detail and opens up wavelengths inaccessible from the ground. In this work we constrain the carbon and oxygen isotopes 13
Weak-lensing Mass Bias in Merging Galaxy Clusters
Nagai, Daisuke; Jee, M. James; Finner, Kyle +6 more
Although weak lensing (WL) is a powerful method to estimate a galaxy cluster mass without any dynamical assumptions, a model bias can arise when the cluster density profile departs from the assumed model profile. In a merging system, the bias is expected to become most severe because the constituent halos undergo significant structural changes. In…