Search Publications
The Fast X-Ray Transient XRT 210423 and Its Host Galaxy
Bauer, F. E.; Dhillon, V. S.; Littlefair, S. P. +8 more
Fast X-ray Transients (FXTs) are X-ray flares with durations ranging from a few hundred seconds to a few hours. Possible origins include the tidal disruption of a white dwarf by an intermediate-mass black hole, a supernova shock breakout, or a binary neutron star merger. We present the X-ray light curve and spectrum as well as deep optical imaging…
[O I] 6300 Å emission as a probe of external photoevaporation of protoplanetary discs
Henney, W. J.; Haworth, Thomas J.; Ballabio, Giulia
We study the utility of the [O I] 6300 Å forbidden line for identifying and interpreting externally driven photoevaporative winds in different environments and at a range of distances. Thermally excited [O I] 6300 Å is a well-known tracer of inner disc winds, so any external contribution needs to be distinguishable. In external winds, the line is …
Phase-space Properties and Chemistry of the Sagittarius Stellar Stream Down to the Extremely Metal-poor ([Fe/H] ≲ -3) Regime
Lee, Young Sun; Chiappini, Cristina; Limberg, Guilherme +6 more
In this work, we study the phase-space and chemical properties of the Sagittarius (Sgr) stream, the tidal tails produced by the ongoing destruction of the Sgr dwarf spheroidal (dSph) galaxy, focusing on its very metal-poor (VMP; [Fe/H] < -2) content. We combine spectroscopic and astrometric information from SEGUE and Gaia EDR3, respectively, wi…
UV-optical Emission of AB Aur b Is Consistent with Scattered Stellar Light
Herczeg, Gregory J.; Zhou, Yifan; Kraus, Adam L. +12 more
The proposed protoplanet AB Aur b is a spatially concentrated emission source imaged in the millimeter-wavelength disk gap of the Herbig Ae/Be star AB Aur. Its near-infrared spectrum and absence of strong polarized light have been interpreted as evidence supporting the protoplanet interpretation. However, the complex scattered-light structures in …
An 600 pc View of the Strongly Lensed, Massive Main-sequence Galaxy J0901: A Baryon-dominated, Thick Turbulent Rotating Disk with a Clumpy Cold Gas Ring at z = 2.259
Lutz, D.; Förster Schreiber, N. M.; Genzel, R. +19 more
We present a high-resolution kinematic study of the massive main-sequence star-forming galaxy (SFG) SDSS J090122.37+181432.3 (J0901) at z = 2.259, using ~0.″36 Atacama Large Millimeter/submillimeter Array CO(3-2) and ~0.″1-0.″5 SINFONI/VLT Hα observations. J0901 is a rare, strongly lensed but otherwise normal massive ( $\mathrm{log}({M}_{\star }/{…
PENELLOPE. IV. A comparison between optical forbidden lines and H2 UV lines in the Orion OB1b and σ-Ori associations
France, K.; Kóspál, Á.; Siwak, M. +17 more
Context. Observing the spatial distribution and excitation processes of atomic and molecular gas in the inner regions (<20 au) of young (<10 Myr) protoplanetary disks helps us to understand the conditions for the formation and evolution of planetary systems.
Aims: In the framework of the PENELLOPE and ULLYSES projects, we aim to charact…
The dark side of FIRE: predicting the population of dark matter subhaloes around Milky Way-mass galaxies
Sanderson, Robyn; Wetzel, Andrew; Samuel, Jenna +3 more
A variety of observational campaigns seek to test dark matter models by measuring dark matter subhaloes at low masses. Despite their predicted lack of stars, these subhaloes may be detectable through gravitational lensing or via their gravitational perturbations on stellar streams. To set measurable expectations for subhalo populations within Lamb…
Chronology of the chemical enrichment of the old Galactic stellar populations
Smiljanic, R.; Giribaldi, R. E.
Context. Over its history, the Milky Way has accreted several smaller satellite galaxies. These mergers added stars and gas to the Galaxy and affected the properties of the pre-existing stellar populations. Stellar chemical abundances and ages are needed to establish the chronological order of events that occur before, during, and after such merge…
Albatross: a scalable simulation-based inference pipeline for analysing stellar streams in the Milky Way
Weniger, Christoph; Alvey, James; Gerdes, Mathis
Stellar streams are potentially a very sensitive observational probe of galactic astrophysics, as well as the dark matter population in the Milky Way. On the other hand, performing a detailed, high-fidelity statistical analysis of these objects is challenging for a number of key reasons. First, the modelling of streams across their (potentially bi…
Eruption and propagation of twisted flux ropes from the base of the solar corona to 1 au
Auchère, F.; Janvier, M.; Lugaz, N. +3 more
Context. Interplanetary coronal mass ejections (ICMEs) originate from the eruption of complex magnetic structures occurring in our star's atmosphere. Determining the general properties of ICMEs and the physical processes at the heart of their interactions with the solar wind is a hard task, in particular using only unidimensional in situ profiles.…