Search Publications
HD 22496 b: The first ESPRESSO stand-alone planet discovery
Rebolo, R.; Pallé, E.; Zapatero Osorio, M. R. +32 more
Context. The ESPRESSO spectrograph is a new powerful tool developed to detect and characterize extrasolar planets. Its design allows an unprecedented radial velocity precision (down to a few tens of cm s−1) and long-term thermomechanical stability.
Aims: We present the first stand-alone detection of an extrasolar planet by blind ra…
The Blue Straggler Population of the Open Clusters Trumpler 5, Trumpler 20, and NGC 2477
Monaco, L.; Villanova, S.; Carraro, G. +3 more
We present a study based on Gaia DR2 of the population of blue straggler stars in the open clusters Trumpler 5, Trumpler 20, and NGC 2477. All candidates were selected according to their position in the color-magnitude diagram, their proper motion components, and their parallax. We also looked for yellow stragglers, i.e., possible evolved blue str…
Calibration of mid- to far-infrared spectral lines in galaxies
Spinoglio, Luigi; Mordini, Sabrina; Fernández-Ontiveros, Juan Antonio
Context. Mid- to far-infrared (IR) lines are suitable in the study of dust-obscured regions in galaxies because dust extinction strongly decreases with wavelength, and therefore IR spectroscopy allows us to explore the most hidden regions of galaxies, where heavily obscured star formation as well as accretion onto supermassive black holes at the n…
Outbursts and stellar properties of the classical Be star HD 6226
Gies, Douglas R.; Wang, Luqian; Richardson, Noel D. +58 more
The bright and understudied classical Be star HD 6226 has exhibited multiple outbursts in the last several years during which the star grew a viscous decretion disc. We analyse 659 optical spectra of the system collected from 2017 to 2020, along with a ultraviolet spectrum from the Hubble Space Telescope and high cadence photometry from both Trans…
The history of metal enrichment traced by X-ray observations of high-redshift galaxy clusters
Allen, Steven W.; Canning, Rebecca E. A.; McDonald, Michael +7 more
We present the analysis of deep X-ray observations of 10 massive galaxy clusters at redshifts 1.05 < z < 1.71, with the primary goal of measuring the metallicity of the intracluster medium (ICM) at intermediate radii, to better constrain models of the metal enrichment of the intergalactic medium. The targets were selected from X-ray and Suny…
Quiescent galaxies in a virialized cluster at redshift 2: evidence for accelerated size growth
Brammer, G.; Stanford, S. A.; Allen, S. W. +4 more
We present an analysis of the galaxy population in XLSSC 122, an X-ray-selected, virialized cluster at redshift z = 1.98. We utilize Hubble Space Telescope (HST)Wide Field Camera 3 (WFC3) photometry to characterize the activity and morphology of spectroscopically confirmed cluster members. The quiescent fraction is found to be $88^{+4}_{-20}$ per …
TIC 308396022: δ Scuti-γ Doradus hybrid with large-amplitude radial fundamental mode and regular g-mode period spacing
Li, Gang; Bedding, Timothy R.; Murphy, Simon J. +3 more
We analyse the pulsating behaviour of TIC 308396022, based on observations by the TESS mission. The star is a high-amplitude δ Sct star that shows a very rich amplitude spectrum using the 3-yr light curve. Among these frequencies, the strongest peak of f1 = 13.20362567(12) d−1 is identified as the radial fundamental mode, and…
Radio observations of massive stars in the Galactic centre: The Arches Cluster
Herrero-Illana, R.; Alberdi, A.; Najarro, F. +8 more
We present high-angular-resolution radio observations of the Arches cluster in the Galactic centre, one of the most massive young clusters in the Milky Way. The data were acquired in two epochs and at 6 and 10 GHz with the Karl G. Jansky Very Large Array. The rms noise reached is three to four times better than during previous observations and we …
The GALAH Survey: using galactic archaeology to refine our knowledge of TESS target stars
Ting, Yuan-Sen; Morton, Timothy D.; Wittenmyer, Robert A. +29 more
An unprecedented number of exoplanets are being discovered by the Transiting Exoplanet Survey Satellite (TESS). Determining the orbital parameters of these exoplanets, and especially their mass and radius, will depend heavily upon the measured physical characteristics of their host stars. We have cross-matched spectroscopic, photometric, and astro…
ASASSN-18aan: An eclipsing SU UMa-type cataclysmic variable with a 3.6-hr orbital period and a late G-type secondary star
Thorstensen, John R.; Nogami, Daisaku; Sasada, Mahito +41 more
We report photometric and spectroscopic observations of the eclipsing SU UMa-type dwarf nova ASASSN-18aan. We observed the 2018 superoutburst with 2.3 mag brightening and found the orbital period (Porb) to be 0.149454(3) d, or 3.59 hr. This is longward of the period gap, establishing ASASSN-18aan as one of a small number of long-Po…