Search Publications
Dynamical Stellar Mass-to-light Ratio Gradients: Evidence for Very Centrally Concentrated IMF Variations in ETGs?
Bender, Ralf; Thomas, Jens; Erwin, Peter +4 more
Evidence from different probes of the stellar initial mass function (IMF) of massive early-type galaxies (ETGs) has repeatedly converged on IMFs more bottom heavy than in the Milky Way (MW). This consensus has come under scrutiny due to often contradictory results from different methods on the level of individual galaxies. In particular, a number …
The Merian survey: design, construction, and characterization of a filter set optimized to find dwarf galaxies and measure their dark matter halo properties with weak lensing
Johnson, Sean D.; Cai, Zheng; Lin, Xiaojing +28 more
The Merian survey is mapping ~ 850 deg2 of the Hyper Suprime-Cam Strategic Survey Program (HSC-SSP) wide layer with two medium-band filters on the 4-m Victor M. Blanco telescope at the Cerro Tololo Inter-American Observatory, with the goal of carrying the first high signal-to-noise (S/N) measurements of weak gravitational lensing around…
Chemical Cartography of the Sagittarius Stream with Gaia
Price-Whelan, Adrian M.; Ness, Melissa K.; Johnston, Kathryn V. +5 more
The stellar stream connected to the Sagittarius (Sgr) dwarf galaxy is the most massive tidal stream that has been mapped in the Galaxy, and is the dominant contributor to the outer stellar halo of the Milky Way (MW). We present metallicity maps of the Sgr stream, using 34,240 red giant branch stars with inferred metallicities from Gaia BP/RP spect…
DESI Early Data Release Milky Way Survey value-added catalogue
Moustakas, J.; Brooks, D.; Li, T. S. +40 more
We present the stellar value-added catalogue based on the Dark Energy Spectroscopic Instrument (DESI) Early Data Release. The catalogue contains radial velocity and stellar parameter measurements for $\simeq$ 400 000 unique stars observed during commissioning and survey validation by DESI. These observations were made under conditions similar to t…
The Mass of the Large Magellanic Cloud from the Three-dimensional Kinematics of Its Globular Clusters
van der Marel, Roeland P.; Watkins, Laura L.; Bennet, Paul
We estimate the mass of the Large Magellanic Cloud (LMC) using the kinematics of 30 LMC globular clusters (GCs). We combine proper motions measured with the Hubble Space Telescope, Gaia, or a combination of the two, from a recent study by Bennet et al. with literature line-of-sight velocities (LOSVs) to give three components of motion. With these,…
Ground-based and JWST Observations of SN 2022pul. II. Evidence from Nebular Spectroscopy for a Violent Merger in a Peculiar Type Ia Supernova
Temim, Tea; Filippenko, Alexei V.; Coulter, David A. +78 more
We present an analysis of ground-based and JWST observations of SN 2022pul, a peculiar "03fg-like" (or "super-Chandrasekhar") Type Ia supernova (SN Ia), in the nebular phase at 338 days postexplosion. Our combined spectrum continuously covers 0.4–14 µm and includes the first mid-infrared spectrum of a 03fg-like SN Ia. Compared to normal SN I…
Statistical investigation of decayless oscillations in small-scale coronal loops observed by Solar Orbiter/EUI
Van Doorsselaere, Tom; Lim, Daye; Berghmans, David +6 more
Decayless kink oscillations are omnipresent in the solar atmosphere, and they are a viable candidate for coronal heating. Although there have been extensive studies of decayless oscillations in coronal loops with lengths of a few hundred megameters, the properties of these oscillations in small-scale (∼10 mm) loops are yet to be explored. In this …
Ly α emission in low-redshift most metal-deficient compact star-forming galaxies
Schaerer, D.; Thuan, T. X.; Izotov, Y. I. +3 more
We present observations with the Cosmic Origins Spectrograph onboard the Hubble Space Telescope of nine most metal-deficient compact star-forming galaxies with oxygen abundances 12 + log(O/H) = 6.97-7.23, redshifts z = 0.02811-0.13320, and stellar masses M⋆ ≤ 107 M⊙. We aim to study the properties of Ly α emission …
Geological evidence for multiple climate transitions on Early Mars
Kite, Edwin S.; Conway, Susan
Landforms and deposits observed on the Martian surface suggest that Mars' early climate supported rivers and lakes over a time span of more than a billion years. But, like Earth, which has over the past billion years experienced periods of global glaciations and hyperthermals, the climate history of Early Mars may have been intermittent. Here we s…
A first look at spatially resolved star formation at 4.8 < z < 6.5 with JWST FRESCO NIRCam slitless spectroscopy
Matharu, Jasleen; Chisholm, John; Shivaei, Irene +19 more
We present the first results on the spatial distribution of star formation in 454 star-forming galaxies just after the epoch of reionisation (4.8 < z < 6.5) using Hα emission-line maps and F444W imaging that traces the stellar continuum from the JWST FRESCO NIRCam Slitless Spectroscopy Survey. The Hα equivalent width profiles of star-forming…