Search Publications
The COMBS Survey - II. Distinguishing the metal-poor bulge from the halo interlopers
Kobayashi, Chiaki; Marino, Anna F.; Hawkins, Keith +9 more
The metal-poor stars in the bulge are important relics of the Milky Way's formation history, as simulations predict that they are some of the oldest stars in the Galaxy. In order to determine if they are truly ancient stars, we must understand their origins. Currently, it is unclear if the metal-poor stars in the bulge ([Fe/H] < -1 dex) are mer…
C18O, 13CO, and 12CO abundances and excitation temperatures in the Orion B molecular cloud. Analysis of the achievable precision in modeling spectral lines within the approximation of the local thermodynamic equilibrium
Peretto, Nicolas; Hughes, Annie; Kainulainen, Jouni +23 more
Context. CO isotopologue transitions are routinely observed in molecular clouds for the purpose of probing the column density of the gas and the elemental ratios of carbon and oxygen, in addition to tracing the kinematics of the environment.
Aims: Our study is aimed at estimating the abundances, excitation temperatures, velocity field, and ve…
Coronal Conditions for the Occurrence of Type II Radio Bursts
Monstein, Christian; Kouloumvakos, Athanasios; Warmuth, Alexander +5 more
Type II radio bursts are generally observed in association with flare-generated or coronal-mass-ejection-driven shock waves. The exact shock and coronal conditions necessary for the production of type II radio emission are still under debate. Shock waves are important for the acceleration of electrons necessary for the generation of the radio emis…
MUSEQuBES: characterizing the circumgalactic medium of redshift ≈3.3 Ly α emitters
Marino, Raffaella Anna; Wendt, Martin; Wisotzki, Lutz +7 more
We present the first characterization of the circumgalactic medium of Ly α emitters (LAEs), using a sample of 96 z ≈ 3.3 LAEs detected with the VLT/MUSE in fields centred on eight bright background quasars. The LAEs have low Ly α luminosities ($\sim 10^{42}\, \text{erg}\, \text{s}^{-1}$) and star formation rates (SFRs) $\sim 1~\text{M}_\odot \, \t…
The VMC Survey - XLII. Near-infrared period-luminosity relations for RR Lyrae stars and the structure of the Large Magellanic Cloud
Clementini, G.; Ripepi, V.; Garofalo, A. +11 more
We present results from an analysis of ~29 000 RR Lyrae stars located in the Large Magellanic Cloud (LMC). For these objects, near-infrared time-series photometry from the VISTA survey of the Magellanic Clouds system (VMC) and optical data from the Optical Gravitational Lensing Experiment (OGLE) IV survey and the Gaia Data Release 2 catalogue of c…
Dust continuum, CO, and [C I] 1 - 0 lines: self-consistent H2 mass estimates and the possibility of globally CO-'dark' galaxies at z = 0.35
Dunne, L.; Gomez, H. L.; Maddox, S. J. +1 more
We present Atacama Large Millimetre Array observations of a small but statistically complete sample of 12 250-µm-selected galaxies at z = 0.35 designed to measure their dust submillimeter continuum emission as well as their $\rm {^{12}CO(1-0)}$ and atomic carbon [C I](3P1-3P0) spectral lines. This …
The Mass-loss History of the Red Hypergiant VY CMa
Humphreys, Roberta M.; Davidson, Kris; Jones, Terry J. +3 more
Imaging and spectroscopy of the knots, clumps, and extended arcs in the complex ejecta of VY CMa confirm a record of high mass-loss events over the past few hundred years. Hubble Space Telescope/Space Telescope Imaging Spectrograph spectroscopy of numerous small knots close to the star allow us to measure their radial velocities from the strong K …
Blue straggler stars in open clusters using Gaia: dependence on cluster parameters and possible formation pathways
Jadhav, Vikrant V.; Subramaniam, Annapurni
Blue straggler stars (BSSs) are the most massive stars in a cluster formed via binary or higher order stellar interactions. Though the exact nature of such formation scenarios is difficult to pin down, we provide observational constraints on the different possible mechanism. In this quest, we first produce a catalogue of BSSs using Gaia DR2 data. …
HST PanCET Program: A Complete Near-UV to Infrared Transmission Spectrum for the Hot Jupiter WASP-79b
Nikolov, Nikolay; Sing, David K.; MacDonald, Ryan J. +12 more
We present a new optical transmission spectrum of the hot Jupiter WASP-79b. We observed three transits with the STIS instrument mounted on the Hubble Space Telescope (HST), spanning 0.3-1.0 µm. Combining these transits with previous observations, we construct a complete 0.3-5.0 µm transmission spectrum of WASP-79b. Both HST and ground-…
Temperature and Distance Dependence of Tidal Circularization in Close Binaries: A Catalog of Eclipsing Binaries in the Southern Hemisphere Observed by the TESS Satellite
Albrecht, Simon; Justesen, Anders B.
Tidal forces are important for understanding how close binary stars and compact exoplanetary systems form and evolve. However, tides are difficult to model, and significant uncertainties exist about the strength of tides. Here, we investigate tidal circularization in close binaries using a large sample of well-characterized eclipsing systems. We s…