Search Publications

The Atari Disk, a Metal-poor Stellar Population in the Disk System of the Milky Way
DOI: 10.3847/1538-4357/ac8102 Bibcode: 2022ApJ...936...78M

Frebel, Anna; Mardini, Mohammad K.; Chiti, Anirudh +3 more

We have developed a chemodynamical approach to assign 36,010 metal-poor SkyMapper stars to various Galactic stellar populations. Using two independent techniques (velocity and action space behavior), Gaia EDR3 astrometry, and photometric metallicities, we selected stars with the characteristics of the "metal-weak" thick-disk population by minimizi…

2022 The Astrophysical Journal
Gaia 43
New Roads to the Small-scale Universe: Measurements of the Clustering of Matter with the High-redshift UV Galaxy Luminosity Function
DOI: 10.3847/2041-8213/ac5e9c Bibcode: 2022ApJ...928L..20S

Muñoz, Julian B.; Sabti, Nashwan; Blas, Diego

The epochs of cosmic dawn and reionization present promising avenues for understanding the role of dark matter (DM) in our cosmos. The first galaxies that populated the universe during these eras resided in DM halos that were much less massive than their counterparts today. Consequently, observations of such galaxies can provide us with a handle o…

2022 The Astrophysical Journal
eHST 43
First JWST observations of a gravitational lens. Mass model from new multiple images with near-infrared observations of SMACS J0723.3−7327
DOI: 10.1051/0004-6361/202244517 Bibcode: 2022A&A...666L...9C

Brammer, G.; Vanzella, E.; Mercurio, A. +4 more

We present our lens mass model of SMACS J0723.3−7327, the first strong gravitational lens observed by the James Webb Space Telescope (JWST). We use data from the Hubble Space Telescope and the Multi Unit Spectroscopic Explorer (MUSE) to build our `pre-JWST' lens model and then refine it with newly available JWST near-infrared imaging in our JWST m…

2022 Astronomy and Astrophysics
eHST JWST 43
Black-hole-triggered star formation in the dwarf galaxy Henize 2-10
DOI: 10.1038/s41586-021-04215-6 Bibcode: 2022Natur.601..329S

Schutte, Zachary; Reines, Amy E.

Black-hole-driven outflows have been observed in some dwarf galaxies with active galactic nuclei1, and probably play a role in heating and expelling gas (thereby suppressing star formation), as they do in larger galaxies2. The extent to which black-hole outflows can trigger star formation in dwarf galaxies is unclear, because…

2022 Nature
eHST 43
The prevalence of galaxy overdensities around UV-luminous Lyman 𝛼 emitters in the Epoch of Reionization
DOI: 10.1093/mnras/stac1908 Bibcode: 2022MNRAS.515.5790L

Laporte, N.; Zitrin, A.; Oesch, P. A. +19 more

Before the end of the Epoch of Reionization, the Hydrogen in the Universe was predominantly neutral. This leads to a strong attenuation of Ly α lines of z ≳ 6 galaxies in the intergalactic medium. Nevertheless, Ly α has been detected up to very high redshifts (z ~ 9) for several especially UV luminous galaxies. Here, we test to what extent the gal…

2022 Monthly Notices of the Royal Astronomical Society
eHST 43
The BAyesian STellar algorithm (BASTA): a fitting tool for stellar studies, asteroseismology, exoplanets, and Galactic archaeology
DOI: 10.1093/mnras/stab2911 Bibcode: 2022MNRAS.509.4344A

Christensen-Dalsgaard, J.; Weiss, A.; Serenelli, A. M. +16 more

We introduce the public version of the BAyesian STellar Algorithm (BASTA), an open-source code written in PYTHON to determine stellar properties based on a set of astrophysical observables. BASTA has been specifically designed to robustly combine large data sets that include asteroseismology, spectroscopy, photometry, and astrometry. We describe t…

2022 Monthly Notices of the Royal Astronomical Society
Gaia 43
The updated BASTI stellar evolution models and isochrones - III. White dwarfs
DOI: 10.1093/mnras/stab3359 Bibcode: 2022MNRAS.509.5197S

Salaris, Maurizio; Cassisi, Santi; Pietrinferni, Adriano +1 more

We present new cooling models for carbon-oxygen white dwarfs (WDs) with both H- and He-atmospheres, covering the whole relevant mass range, to extend our updated BASTI (a Bag of Stellar Tracks and Isochrones) stellar evolution archive. They have been computed using core chemical stratifications obtained from new progenitor calculations, adopting a…

2022 Monthly Notices of the Royal Astronomical Society
Gaia 42
The Gaia-ESO Survey: Membership probabilities for stars in 63 open and 7 globular clusters from 3D kinematics
DOI: 10.1093/mnras/stab3032 Bibcode: 2022MNRAS.509.1664J

Gilmore, G.; Montes, D.; Prada Moroni, P. G. +26 more

Spectroscopy from the final internal data release of the Gaia-ESO Survey (GES) has been combined with Gaia EDR3 to assign membership probabilities to targets observed towards 63 Galactic open clusters and 7 globular clusters. The membership probabilities are based chiefly on maximum likelihood modelling of the 3D kinematics of the targets, separat…

2022 Monthly Notices of the Royal Astronomical Society
Gaia 42
Hot subdwarfs in close binaries observed from space. I. Orbital, atmospheric, and absolute parameters, and the nature of their companions
DOI: 10.1051/0004-6361/202244214 Bibcode: 2022A&A...666A.182S

Geier, S.; Pelisoli, I.; Schaffenroth, V. +2 more

Context. About a third of the hot subdwarfs of spectral type B (sdBs), which are mostly core-helium-burning objects on the extreme horizontal branch, are found in close binaries with cool, low-mass stellar, substellar, or white dwarf companions. They can show light variations due to different phenomena.
Aims: Many hot subdwarfs now have space…

2022 Astronomy and Astrophysics
Gaia 42
Exploring the Sgr-Milky Way-disk Interaction Using High-resolution N-body Simulations
DOI: 10.3847/1538-4357/ac5021 Bibcode: 2022ApJ...927..131B

Bovy, Jo; Hunt, Jason A. S.; Bennett, Morgan

The ongoing merger of the Sagittarius (Sgr) dwarf galaxy with the Milky Way is believed to strongly affect the dynamics of the Milky Way's disk. We present a suite of 13 N-body simulations, with 500 million-1 billion particles, modeling the interaction between the Sgr dwarf galaxy and the Galactic disk. To quantify the perturbation to the disk's s…

2022 The Astrophysical Journal
Gaia 42