Search Publications
SPICE: the connection between cosmic reionization and stellar feedback in the first galaxies
Pakmor, Rüdiger; Costa, Tiago; Bhagwat, Aniket +2 more
We present SPICE, a new suite of radiation-hydrodynamic, cosmological simulations targeting the epoch of reionization. The goal of these simulations is to systematically probe a variety of stellar feedback models, including 'bursty' and 'smooth' forms of supernova energy injection, as well as poorly explored physical scenarios such as hypernova ex…
The On-axis Jetted Tidal Disruption Event AT2022cmc: X-Ray Observations and Broadband Spectral Modeling
Kulkarni, S. R.; Cenko, S. Bradley; Gezari, Suvi +5 more
AT2022cmc was recently reported as the first on-axis jetted tidal disruption event (TDE) discovered in the last decade, and the fourth on-axis jetted TDE candidate known so far. In this work, we present NuSTAR hard X-ray (3–30 keV) observations of AT2022cmc, as well as soft X-ray (0.3–6 keV) observations obtained by NICER, Swift, and XMM-Newton. O…
Semi-analytic modelling of Pop. III star formation and metallicity evolution - I. Impact on the UV luminosity functions at z = 9-16
Qin, Yuxiang; Balu, Sreedhar; Wyithe, J. Stuart B. +1 more
We implemented Population III (Pop. III) star formation in mini-haloes within the MERAXES semi-analytic galaxy formation and reionization model, run on top of a N-body simulation with L = 10 h-1 cMpc with 20483 particles resolving all dark matter haloes down to the mini-haloes (~105 M⊙). Our modelling in…
The Radcliffe Wave is oscillating
Alves, João; Zucker, Catherine; Goodman, Alyssa A. +6 more
Our Sun lies within 300 parsecs of the 2.7-kiloparsecs-long sinusoidal chain of dense gas clouds known as the Radcliffe Wave1. The structure's wave-like shape was discovered using three-dimensional dust mapping, but initial kinematic searches for oscillatory motion were inconclusive2-7. Here we present evidence that the Radcl…
Modeling the molecular gas content and CO-to-H2 conversion factors in low-metallicity star-forming dwarf galaxies
Ramambason, L.; Lebouteiller, V.; Madden, S. C. +8 more
Context. Low-metallicity dwarf galaxies often show no or little CO emission, despite the intense star formation observed in local samples. Both simulations and resolved observations indicate that molecular gas in low-metallicity galaxies may reside in small dense clumps, surrounded by a substantial amount of more diffuse gas that is not traced by …
Classification and parameterization of a large Gaia sample of white dwarfs using XP spectra
Jordan, S.; Barstow, M. A.; Bergeron, P. +3 more
Context. The latest Gaia data release in July 2022, DR3, in addition to the refinement of the astrometric and photometric parameters from DR2, added a number of important data products to those available in earlier releases, including radial velocity data, information on stellar multiplicity, and XP spectra of a selected sample of stars. Gaia has …
pop-cosmos: A Comprehensive Picture of the Galaxy Population from COSMOS Data
Leistedt, Boris; Peiris, Hiranya V.; Leja, Joel +4 more
We present pop-cosmos: a comprehensive model characterizing the galaxy population, calibrated to 140,938 (r < 25 selected) galaxies from the Cosmic Evolution Survey (COSMOS) with photometry in 26 bands from the ultraviolet to the infrared. We construct a detailed forward model for the COSMOS data, comprising: a population model describing the j…
Towards an astronomical foundation model for stars with a transformer-based model
Bovy, Jo; Leung, Henry W.
Rapid strides are currently being made in the field of artificial intelligence using transformer-based models like Large Language Models (LLMs). The potential of these methods for creating a single, large, versatile model in astronomy has not yet been explored. In this work, we propose a framework for data-driven astronomy that uses the same core …
Discovery of the local counterpart of disc galaxies at z > 4: The oldest thin disc of the Milky Way using Gaia-RVS
Guiglion, G.; Chiappini, C.; Queiroz, A. B. +5 more
Context. JWST recently detected numerous disc galaxies at high redshifts, and there have been observations of cold disc galaxies at z > 4 with ALMA. In the Milky Way (MW), recent studies highlight the presence of metal-poor stars in cold-disc orbits, suggesting an ancient disc. This prompts two fundamental questions. The first refers to the tim…
High turbulence in the IM Lup protoplanetary disk. Direct observational constraints from CN and C2H emission
Miotello, A.; van Dishoeck, E. F.; Bergin, E. A. +4 more
Context. Constraining turbulence in disks is key to understanding their evolution via the transport of angular momentum. Measurements of high turbulence remain elusive, and methods for estimating turbulence mostly rely on complex radiative transfer models of the data. Using the disk emission from IM Lup, a source proposed to be undergoing magneto-…