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Exoplanet transit spectroscopy with JWST NIRSpec: diagnostics and homogeneous case study of WASP-39 b
DOI: 10.1093/mnras/stae1230 Bibcode: 2024MNRAS.531.2731S

Madhusudhan, Nikku; Constantinou, Savvas; Sarkar, Subhajit +1 more

The JWST has ushered in a new era of exoplanet transit spectroscopy. Among the JWST instruments, the Near-Infrared Spectrograph (NIRSpec) has the most extensive set of configurations for exoplanet time-series observations. The NIRSpec Prism and G395H grating represent two extremes in NIRSpec instrument modes, with the Prism spanning a wider spectr…

2024 Monthly Notices of the Royal Astronomical Society
JWST 6
A strontium-rich ultra-metal-poor star in the Atari disc component
DOI: 10.1093/mnrasl/slad197 Bibcode: 2024MNRAS.529L..60M

Frebel, Anna; Mardini, Mohammad K.; Chiti, Anirudh

We report on the discovery of the first ultra-metal-poor (UMP) star 2MASS J20500194-6613298 (J2050-6613; [Fe/H] = -4.05) selected from the Gaia BP/RP spectral catalogue that belongs to the ancient Atari disc component. We obtained a high-resolution spectrum for the star with the MIKE spectrograph on the Magellan-Clay telescope. J2050-6613 displays…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 6
Deconvolution of JWST/MIRI Images: Applications to an Active Galactic Nucleus Model and GATOS Observations of NGC 5728
DOI: 10.3847/1538-3881/ad1886 Bibcode: 2024AJ....167...96L

Rouan, D.; Rigopoulou, D.; Stalevski, M. +32 more

The superb image quality, stability, and sensitivity of JWST permit deconvolution techniques to be pursued with a fidelity unavailable to ground-based observations. We present an assessment of several deconvolution approaches to improve image quality and mitigate the effects of the complex JWST point-spread function (PSF). The optimal deconvolutio…

2024 The Astronomical Journal
eHST JWST 6
Scylla. I. A Pure-parallel, Multiwavelength Imaging Survey of the ULLYSES Fields in the LMC and SMC
DOI: 10.3847/1538-4365/ad6de2 Bibcode: 2024ApJS..275....5M

McQuinn, Kristen B. W.; Dolphin, Andrew E.; Murray, Claire E. +17 more

Scylla is a deep Hubble Space Telescope (HST) survey of the stellar populations, interstellar medium, and star formation in the LMC and SMC. As a pure-parallel complement to the Ultraviolet Legacy Library of Young Stars as Essential Standards (ULLYSES) survey, Scylla obtained 342 orbits of ultraviolet (UV) through near-IR imaging of the LMC and SM…

2024 The Astrophysical Journal Supplement Series
eHST 6
Extreme ionizing properties of a metal-poor, MUV ≃ ‑12 star complex in the first gigayear
DOI: 10.1051/0004-6361/202451696 Bibcode: 2024A&A...691A.251V

Frye, B. L.; Dickinson, M.; Zanella, A. +38 more

We report the serendipitous discovery of a faint (MUV > ‑12.2), low-metallicity (Z ∼ 0.02 Z⊙) ionizing source, dubbed T2c, with a spectroscopic redshift of z = 6.146. T2c is part of a larger structure amplified by the Hubble Frontier Field galaxy cluster MACSJ0416 and was observed with the James Webb Space Telescope (JWST) NIRSpec in…

2024 Astronomy and Astrophysics
eHST JWST 6
Introducing the Condor array telescope II - deep imaging observations of the edge-on spiral galaxy NGC 5907 and the NGC 5866 Group: yet another view of the iconic stellar stream
DOI: 10.1093/mnras/stad3806 Bibcode: 2024MNRAS.529..197L

Walter, Frederick M.; Shara, Michael M.; Lanzetta, Kenneth M. +6 more

We used the Condor array telescope to obtain deep imaging observations through the luminance filter of the entirety of the NGC 5866 Group, including a very extended region surrounding the galaxy NGC 5907 and its stellar stream. We find that the stellar stream consists of a single curved structure that stretches 220 kpc from a brighter eastern stre…

2024 Monthly Notices of the Royal Astronomical Society
AKARI Gaia 6
Spectroscopic evidence of cool plasma in quiet Sun small-scale brightenings detected by HRIEUV on board Solar Orbiter
DOI: 10.1051/0004-6361/202450439 Bibcode: 2024A&A...688A..77D

Parenti, S.; Bocchialini, K.; Dolliou, A.

Context. A large number of small and short-lived EUV brightenings have been detected in the quiet Sun (QS) over the past three years by the High Resolution Imager of the Extreme Ultraviolet Imager (HRIEUV) on board Solar Orbiter. It remains uncertain whether these events reach coronal temperatures and, thus, whether they directly contribute to cor…

2024 Astronomy and Astrophysics
Hinode IRIS SolarOrbiter 6
Detection of an Earth-sized exoplanet orbiting the nearby ultracool dwarf star SPECULOOS-3
DOI: 10.1038/s41550-024-02271-2 Bibcode: 2024NatAs...8..865G

Ikuta, Kai; Triaud, Amaury H. M. J.; Tamura, Motohide +82 more

Located at the bottom of the main sequence, ultracool dwarf stars are widespread in the solar neighbourhood. Nevertheless, their extremely low luminosity has left their planetary population largely unexplored, and only one of them, TRAPPIST-1, has so far been found to host a transiting planetary system. In this context, we present the SPECULOOS pr…

2024 Nature Astronomy
Gaia JWST 6
Hubble Space Telescope Images of SN 1987A: Evolution of the Ejecta and the Equatorial Ring from 2009 to 2022
DOI: 10.3847/1538-4357/ad36cc Bibcode: 2024ApJ...966..238R

Matsuura, Mikako; Fransson, Claes; Kirshner, Robert P. +9 more

Supernova (SN) 1987A offers a unique opportunity to study how a spatially resolved SN evolves into a young SN remnant. We present and analyze Hubble Space Telescope (HST) imaging observations of SN 1987A obtained in 2022 and compare them with HST observations from 2009 to 2021. These observations allow us to follow the evolution of the equatorial …

2024 The Astrophysical Journal
eHST 6
Constraining Wind-driven Accretion onto Gaia BH3 with Chandra
DOI: 10.3847/1538-4357/ad6f96 Bibcode: 2024ApJ...973...75C

Cappelluti, Nico; Hasinger, Günther; Pacucci, Fabio

Gaia BH3 is the most massive known stellar-origin black hole in the Milky Way, with a mass M ≈ 33 M . Detected from Gaia's astrometry, this black hole is in the mass range of those observed via gravitational waves, whose nature is still highly debated. Hosted in a binary system with a companion giant star that is too far a…

2024 The Astrophysical Journal
Gaia 6