Search Publications
A new look at local ultraluminous infrared galaxies: the atlas and radiative transfer models of their complex physics
Clements, D. L.; Wang, L.; Farrah, D. +11 more
We present the ultraviolet to submillimetre spectral energy distributions (SEDs) of the HERschel Ultra Luminous Infrared Galaxy Survey (HERUS) sample of 42 local ultraluminous infrared galaxies (ULIRGs) and fit them with a Markov chain Monte Carlo code using the CYprus models for Galaxies and their NUclear Spectra (CYGNUS) radiative transfer model…
The flaring TESS Objects of Interest: flare rates for all two-minute cadence TESS planet candidates
Howard, Ward S.
Although more than 5000 TESS Objects of Interest have been catalogued, no comprehensive survey of the flare rates of their host stars exists. We perform the first flare survey of all 2250 non-retired TOIs with 2-min cadence light curves to measure or place upper limits on their flare rates. We find 93 candidates orbit flare stars and measure their…
Non-detection of 6Li in Spite plateau stars with ESPRESSO
Lind, Karin; Nordlander, Thomas; Reggiani, Henrique +3 more
The detection of 6Li in Spite plateau stars contradicts the standard big bang nucleosynthesis prediction, known as the second cosmological lithium problem. We measure the isotopic ratio 6Li/7Li in three Spite plateau stars: HD 84937, HD 140283, and LP 815-43. We use 3D non-local thermodynamic equilibrium radiative …
The homogeneity of chemical abundances in H II regions of the Magellanic Clouds
García-Rojas, J.; Esteban, C.; Rodríguez, M. +2 more
We use very deep spectra obtained with the Ultraviolet-Visual Echelle Spectrograph at the Very Large Telescope to derive physical conditions and chemical abundances of four H II regions of the Large Magellanic Cloud (LMC) and four H II regions of the Small Magellanic Cloud (SMC). The observations cover the spectral range 3100-10400 Å with a spectr…
A complex multiphase DLA associated with a compact group at z = 2.431 traces accretion, outflows, and tidal streams
Charlton, Jane C.; Kacprzak, Glenn G.; Churchill, Christopher W. +4 more
As part of our program to identify host galaxies of known z = 2-3 Mg II absorbers with the Keck Cosmic Web Imager (KCWI), we discovered a compact group giving rise to a z = 2.431 DLA with ultrastrong Mg II absorption in quasar field J234628+124859. The group consists of four star-forming galaxies within 8-28 kpc and v ~ 40-340 km s-1 of…
Kinematic footprint of the Milky Way spiral arms in Gaia EDR3
Pérez-Villegas, Angeles; Martinez-Medina, Luis; Peimbert, Antonio
The Milky Way spiral arms are well established from star counts as well as from the locus of molecular clouds and other young objects; however, they have only recently started to be observed from a kinematics point of view. Using the kinematics of thin disc stars in Gaia EDR3 around the extended solar neighbourhood, we create x-y projections colou…
Deep learning-based super-resolution and de-noising for XMM-newton images
Valtchanov, Ivan; Verdugo, Eva; Lieu, Maggie +6 more
The field of artificial intelligence based image enhancement has been rapidly evolving over the last few years and is able to produce impressive results on non-astronomical images. In this work, we present the first application of Machine Learning based super-resolution (SR) and de-noising (DN) to enhance X-ray images from the European Space Agenc…
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…
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…
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. …