Search Publications

Reaching for the stars - JWST/NIRSpec spectroscopy of a lensed star candidate at z = 4.76
DOI: 10.1093/mnrasl/slad135 Bibcode: 2024MNRAS.527L...7F

Ravindranath, Swara; Wilkins, Stephen M.; Mahler, Guillaume +31 more

We present JWST/NIRSpec observations of a highly magnified star candidate at a photometric redshift of zphot ≃ 4.8, previously detected in JWST/NIRCam imaging of the strong lensing (SL) cluster MACS J0647+7015 (z = 0.591). The spectroscopic observation allows us to precisely measure the redshift of the host arc at zspec = 4.7…

2024 Monthly Notices of the Royal Astronomical Society
JWST 17
Carnegie Supernova Project I and II: Measurements of H 0 Using Cepheid, Tip of the Red Giant Branch, and Surface Brightness Fluctuation Distance Calibration to Type Ia Supernovae
DOI: 10.3847/1538-4357/ad3e63 Bibcode: 2024ApJ...970...72U

Gall, Christa; Ryder, Stuart D.; Morrell, Nidia +44 more

We present an analysis of Type Ia supernovae (SNe Ia) from the Carnegie Supernova Project I and II and extend the Hubble diagram from optical to near-infrared wavelengths (uBgVriYJH). We calculate the Hubble constant, H 0, using various distance calibrators: Cepheids, the tip of the red giant branch (TRGB), and surface brightness fluctu…

2024 The Astrophysical Journal
eHST 17
Expanded Sample of Small Magellanic Cloud Ultraviolet Dust Extinction Curves: Correlations between the 2175 Å Bump, q PAH, Ultraviolet Extinction Shape, and N(H I)/A(V)
DOI: 10.3847/1538-4357/ad4be1 Bibcode: 2024ApJ...970...51G

Murray, Claire E.; Gordon, Karl D.; Fitzpatrick, E. L. +7 more

The Small Magellanic Cloud (SMC) shows a large variation in ultraviolet (UV) dust extinction curves, ranging from Milky Way (MW) like to significantly steeper curves with no detectable 2175 Å bump. This result is based on a sample of only nine sight lines. From Hubble Space Telescope Space Telescope Imaging Spectrograph and IUE spectra of OB stars…

2024 The Astrophysical Journal
Herschel IUE eHST 17
Black Hole Spin Measurements in LMC X-1 and Cyg X-1 Are Highly Model Dependent
DOI: 10.3847/1538-4357/ad1b60 Bibcode: 2024ApJ...962..101Z

Zdziarski, Andrzej A.; Szanecki, Michał; Dewangan, Gulab +4 more

The black hole spin parameter, a *, was measured to be close to its maximum value of 1 in many accreting X-ray binaries. In particular, a * ≳ 0.9 was found in a number of studies of LMC X-1. These measurements were claimed to take into account both statistical and systematic uncertainties. We perform new measurements using a …

2024 The Astrophysical Journal
Suzaku 17
To be, or not to be: Balmer breaks in high-z galaxies with JWST
DOI: 10.1093/mnras/stae323 Bibcode: 2024MNRAS.529.1299V

Coe, Dan; Bradley, Larry D.; Zackrisson, Erik +7 more

Standard models of structure formation allow us to predict the cosmic timescales relevant for the onset of star formation and the assembly history of galaxies at high redshifts (z > 10). The strength of the Balmer break represents a well-known diagnostic of the age and star formation history of galaxies, which enables us to compare observations…

2024 Monthly Notices of the Royal Astronomical Society
JWST 17
A Comprehensive Correction of the Gaia DR3 XP Spectra
DOI: 10.3847/1538-4365/ad18b1 Bibcode: 2024ApJS..271...13H

Xiang, Maosheng; Huang, Yang; Niu, Zexi +7 more

By combining spectra from the CALSPEC and NGSL, as well as spectroscopic data from the LAMOST Data Release 7 (DR7), we have analyzed and corrected the systematic errors of the Gaia DR3 BP/RP (XP) spectra. The errors depend on the normalized spectral energy distribution (simplified by two independent "colors") and G magnitude. Our corrections are a…

2024 The Astrophysical Journal Supplement Series
Gaia eHST 17
2D disc modelling of the JWST line spectrum of EX Lupi
DOI: 10.1051/0004-6361/202347730 Bibcode: 2024A&A...683A.219W

Woitke, P.; Kamp, I.; Ábrahám, P. +3 more

We introduce a number of improvements to the thermo-chemical disc modelling code PRODIMO and new theoretical approaches that can be used to better predict and analyse the JWST line spectra of protoplanetary discs. We developed a new line escape probability method for disc geometries, and a new scheme for dust settling, and discuss how to apply UV …

2024 Astronomy and Astrophysics
Herschel XMM-Newton 17
AGNs in massive galaxy clusters: Role of galaxy merging, infalling groups, cluster mass, and dynamical state
DOI: 10.1051/0004-6361/202348212 Bibcode: 2024A&A...684A.111K

Koulouridis, E.; Drigga, E.; Gkini, A.

Context. There is compelling evidence that active galactic nuclei (AGNs) in high-density regions have undergone a different evolution than their counterparts in the field, indicating that they are strongly affected by their environment. However, we still lack a comprehensive understanding of the dominant mechanisms that trigger the nucleus and the…

2024 Astronomy and Astrophysics
XMM-Newton eHST 17
Anatomy of an ionized bubble: NIRCam grism spectroscopy of the z = 6.6 double-peaked Lyman-α emitter COLA1 and its environment
DOI: 10.1051/0004-6361/202450318 Bibcode: 2024A&A...689A..44T

Conroy, Charlie; Sobral, David; Tacchella, Sandro +10 more

The increasingly neutral intergalactic gas at z > 6 impacts the Lyman-α (Lyα) flux observed from galaxies. One luminous galaxy, COLA1, stands out because of its unique double-peaked Lyα line at z = 6.6, unseen in any simulation of reionization. Here, we present JWST/NIRCam wide-field slitless spectroscopy in a 21 arcmin2 field center…

2024 Astronomy and Astrophysics
JWST 17
SMILES: A Prototype JWST Multiband Mid-infrared Survey
DOI: 10.3847/1538-4357/ad6cd2 Bibcode: 2024ApJ...975...83R

Shivaei, Irene; Lyu, Jianwei; Alberts, Stacey +4 more

The Mid-Infrared Instrument (MIRI) for JWST is supplied with a suite of imaging band-pass filters optimized for full spectral coverage in eight intermediate-width bands from 5 to 26 µm and a narrower one at 11.3 µm. This contrasts with previous infrared space telescopes, which generally have provided only two broad bands, one near 10 &…

2024 The Astrophysical Journal
ISO 17