Search Publications
JWST Validates HST Distance Measurements: Selection of Supernova Subsample Explains Differences in JWST Estimates of Local H 0
Casertano, Stefano; Filippenko, Alexei V.; Li, Siyang +16 more
We cross-check the Hubble Space Telescope (HST) Cepheid/Type Ia supernova (SN Ia) distance ladder, which yields the most precise local H 0, against early James Webb Space Telescope (JWST) subsamples (∼1/4 of the HST sample) from SH0ES and CCHP, calibrated only with NGC 4258. We find HST Cepheid distances agree well (∼1σ) with all combin…
A massive interacting galaxy 510 million years after the Big Bang
Santini, Paola; Castellano, Marco; Fontana, Adriano +26 more
James Webb Space Telescope observations have spectroscopically confirmed the existence of galaxies as early as 300 Myr after the Big Bang and with a higher number density than what was expected based on galaxy formation models and Hubble Space Telescope observations. Yet, most sources confirmed spectroscopically so far in the first 500 Myr have re…
The Initial Mass Function Based on the Full-sky 20 pc Census of ∼3600 Stars and Brown Dwarfs
Tsai, Chao-Wei; Mamajek, Eric; Gonzales, Eileen C. +83 more
A complete accounting of nearby objects—from the highest-mass white dwarf progenitors down to low-mass brown dwarfs—is now possible, thanks to an almost complete set of trigonometric parallax determinations from Gaia, ground-based surveys, and Spitzer follow-up. We create a census of objects within a Sun-centered sphere of 20 pc radius and check p…
Possible Hycean conditions in the sub-Neptune TOI-270 d
Madhusudhan, Nikku; Holmberg, Måns
The JWST has ushered in a new era in atmospheric characterisations of temperate low-mass exoplanets with recent detections of carbon-bearing molecules in the candidate Hycean world K2-18 b. We investigated JWST observations of the TOI-270 system, with two sub-Neptunes simultaneously transiting the nearby M dwarf during the visit. We report our atm…
The UNCOVER Survey: A First-look HST+JWST Catalog of Galaxy Redshifts and Stellar Population Properties Spanning 0.2 ≲ z ≲ 15
Papovich, Casey; Franx, Marijn; Muzzin, Adam +41 more
The recent UNCOVER survey with the James Webb Space Telescope (JWST) exploits the nearby cluster A2744 to create the deepest view of our Universe to date by leveraging strong gravitational lensing. In this work, we perform photometric fitting of more than 50,000 robustly detected sources out to z ~ 15. We show the redshift evolution of stellar age…
Cygnus X-3 revealed as a Galactic ultraluminous X-ray source by IXPE
Ingram, Adam; Kaaret, Philip; Wu, Kinwah +127 more
The accretion of matter by compact objects can be inhibited by radiation pressure if the luminosity exceeds a critical value known as the Eddington limit. The discovery of ultraluminous X-ray sources has shown that accretion can proceed even when the apparent luminosity considerably exceeds this limit. A high apparent luminosity might be produced …
The more the merrier: SRG/eROSITA discovers two further galaxies showing X-ray quasi-periodic eruptions
Gromadzki, M.; Salvato, M.; Liu, Z. +20 more
X-ray quasi-periodic eruptions (QPEs) are a novel addition to the group of extragalactic transients. With only a select number of known sources, and many more models published trying to explain them, we are so far limited in our understanding by small number statistics. In this work, we report the discovery of two further galaxies showing QPEs, he…
Quantifying the Effects of Known Unknowns on Inferred High-redshift Galaxy Properties: Burstiness, IMF, and Nebular Physics
Labbé, Ivo; Bezanson, Rachel; Price, Sedona H. +15 more
The era of the James Webb Space Telescope ushers stellar population models into uncharted territories, particularly at the high-redshift frontier. In a companion paper, we apply the Prospector Bayesian framework to jointly infer galaxy redshifts and stellar population properties from broadband photometry as part of the UNCOVER survey. Here we pres…
PDRs4All: III. JWST's NIR spectroscopic view of the Orion Bar
Hartigan, Patrick; Zhang, Yong; Gordon, Karl D. +135 more
Context. JWST has taken the sharpest and most sensitive infrared (IR) spectral imaging observations ever of the Orion Bar photodis-sociation region (PDR), which is part of the nearest massive star-forming region the Orion Nebula, and often considered to be the 'prototypical' strongly illuminated PDR. Aims. We investigate the impact of radiative fe…
The Pristine survey: XXIII. Data Release 1 and an all-sky metallicity catalogue based on Gaia DR3 BP/RP spectro-photometry
Fouesneau, Morgan; Sestito, Federico; McConnachie, Alan W. +38 more
We used the spectro-photometric information of ∼219 million stars from Gaia's Data Release 3 (DR3) to calculate synthetic, narrowband, metallicity-sensitive CaHK magnitudes that mimic the observations of the Pristine survey, a survey of photometric metallicities of Milky Way stars that has been mapping more than 6500 deg2 of the norther…