Search Publications
zELDA: fitting Lyman alpha line profiles using deep learning
Gronke, Max; Saito, Shun; Bonoli, Silvia +2 more
We present zELDA (redshift Estimator for Line profiles of Distant Lyman Alpha emitters), an open source code to fit Lyman α (Ly α) line profiles. The main motivation is to provide the community with an easy to use and fast tool to analyse Ly α line profiles uniformly to improve the understating of Ly α emitting galaxies. zELDA is based on line pro…
Future constraints on primordial black holes from XGIS-THESEUS
Ghosh, Diptimoy; Sachdeva, Divya; Singh, Praniti
Current observations allow primordial black holes (PBHs) in asteroid mass range 1017- 1022 g to constitute the entire dark matter energy density (barring a small mass range constrained by 21-cm observations). In this work, we explore the possibility of probing PBHs with masses 1017- 1019 g via the upcomi…
Dark and luminous mass components of Omega Centauri from stellar kinematics
Zivick, Paul; Strigari, Louis E.; Evans, Addy J.
We combine proper motion data from Gaia EDR3 and HST with line-of-sight velocity data to study the stellar kinematics of the ω Cen globular cluster. Using a steady-state, axisymmetric dynamical model, we measure the distribution of both the dark and luminous mass components. Assuming both Gaussian and Navarro-Frenk-White mass profiles, depending o…
Chemodynamical Signatures of Bar Resonances in the Galactic Disk: Current Data and Future Prospects
Fragkoudi, Francesca; Wheeler, Adam; Ness, Melissa +2 more
The Galactic disk exhibits complex chemical and dynamical substructure thought to be induced by the bar, spiral arms, and satellites. Here, we explore the chemical signatures of bar resonances in action and velocity space, and characterize the differences between the signatures of corotation (CR) and higher-order resonances using test particle sim…
From ridges to manifolds: 3D characterization of the moving groups in the Milky Way disc
Antoja, T.; Bernet, M.; Monari, G. +4 more
Context. The details of the effect of the bar and spiral arms on the disc dynamics of the Milky Way are still unknown. The stellar velocity distribution in the solar neighbourhood displays kinematic substructures, which are possibly signatures of these processes and of previous accretion events. With the Gaia mission, more details of these signatu…
Dynamically Tagged Groups of Metal-poor Stars. II. The Radial Velocity Experiment Data Release 6
Huang, Yang; Beers, Timothy C.; Placco, Vinicius M. +2 more
Orbital characteristics based on Gaia Early Data Release 3 astrometric parameters are analyzed for ~8000 metal-poor stars ([Fe/H] ≤ -0.8) compiled from the Radial Velocity Experiment (RAVE) Data Release 6. Selected as metal-poor candidates based on broadband photometry, RAVE collected moderate-resolution (R ~ 7500) spectra in the region of the Ca …
Quasars with large proper motions: A selection from the LQAC-5 catalogue combined with Gaia EDR3. Focusing on astrometric and photometric properties
Zacharias, N.; Barache, C.; Lambert, S. +5 more
Context. Thanks to the cross-identification between the Gaia EDR3 (E-Data Release 3) catalogue and the quasars' compiled catalogue LQAC-5 (Large Quasar Astrometric Catalogue-5), accurate astrometric parameters as well as photometric measurements were available for a set of 416 113 quasars.
Aims: After analysing the astrometric and photometric…
Constraining spinning primordial black holes with global 21-cm signal
Natwariya, Pravin Kumar; Nayak, Alekha C.; Srivastava, Tripurari
We study the upper projected bounds on the dark matter fraction in the form of the primordial black holes (PBHs) with a non-zero spin by using the absorption feature in the global 21-cm signal at redshift z ≈ 17. The mass and spin are fundamental properties of a black hole, and they can substantially affect the evaporation rate of the black hole. …
New strong lensing modelling of SDSS J2222+2745 enhanced with VLT/MUSE spectroscopy
Brammer, G.; Grillo, C.; Tozzi, P. +8 more
Context. SDSS J2222+2745, at z = 0.489, is one of the few currently known lens clusters with multiple images (six) of a background (z = 2.801) quasar with measured time delays between two image pairs (with a sub-percent relative error for the longer time delay). Systems of this kind can be exploited as alternative cosmological probes through high-…
AGN accretion and black hole growth across compact and extended galaxy evolution phases
Kocevski, Dale D.; Aird, James; Coil, Alison L.
The extent of black hole growth during different galaxy evolution phases and the connection between galaxy compactness and active galactic nucleus (AGN) activity remain poorly understood. We use Hubble Space Telescope imaging of the CANDELS fields to identify star-forming and quiescent galaxies at z = 0.5-3 in both compact and extended phases and …