Search Publications
GlobULeS - V. UVIT/AstroSat studies of stellar populations in NGC 362: detection of blue lurkers in a globular cluster
Dattatrey, Arvind K.; Yadav, R. K. S.; Subramaniam, Annapurni +4 more
We report the discovery of four blue lurkers with low- and extremely low mass white dwarf (ELM WD) companions in the Galactic globular cluster NGC 362 using AstroSat's Ultra Violet Imaging Telescope (UVIT). We analysed the multiwavelength spectral energy distribution (SED) of far-ultraviolet-bright main-sequence stars using data from the UVIT, Ult…
Nonthermal Motions and Atmospheric Heating of Cool Stars
Airapetian, V. S.; Ayres, T.; Testa, P. +6 more
The magnetic processes associated with the nonthermal broadening of optically thin emission lines appear to carry enough energy to heat the corona and accelerate the solar wind. We investigate whether nonthermal motions in cool stars exhibit the same behavior as on the Sun by analyzing archival stellar spectra taken by the Hubble Space Telescope, …
Two large-scale sloshing cold fronts in the outskirts of the galaxy cluster Abell 3558
Walker, S. A.; Mirakhor, M. S.; Sundquist, M. +1 more
Previous studies of the massive nearby galaxy cluster Abell 3558 reported a cold front around the cluster core, which is attributed to the sloshing of the core as it responds to the gravitational disturbance created by a past minor merger. Here, using XMM-Newton mosaic, we report the detection of two rare large-scale sloshing cold fronts far outsi…
The Magnetic Sensitivity of the (250-278 nm) Fe II Polarization Spectrum
Afonso Delgado, David; del Pino Alemán, Tanausú; Trujillo Bueno, Javier
This paper presents a theoretical investigation of the polarization and magnetic sensitivity of the near-ultraviolet (near-UV) solar spectral lines of Fe II between 250 and 278 nm. In recent years, UV spectropolarimetry has become key to uncovering the magnetism of the upper layers of the solar chromosphere. The unprecedented data obtained by the …
Assessing global trends in Mars magma compositions using ground truth
Head, James W.; Rogers, A. Deanne; McSween, Harry Y. +1 more
Global magmatic trends inferred from gamma-ray, visible/near-infrared, and thermal infrared spectrometers on Mars-orbiting spacecraft have been used to constrain planetary petrogenetic processes and global thermal evolution models. Inferred magmatic trends include temporal variations in the relative proportions of low-Ca and high-Ca pyroxenes, and…
Spinning up a Daze: TESS Uncovers a Hot Jupiter Orbiting the Rapid Rotator TOI-778
Bieryla, Allyson; Latham, David W.; Quinn, Samuel N. +69 more
NASA's Transiting Exoplanet Survey Satellite (TESS) mission has been uncovering a growing number of exoplanets orbiting nearby, bright stars. Most exoplanets that have been discovered by TESS orbit narrow-line, slow-rotating stars, facilitating the confirmation and mass determination of these worlds. We present the discovery of a hot Jupiter orbit…
A Morphological Study of Two Young Multipolar Planetary Nebulae
Hsia, Chih-Hao; Kang, Xiao-Xi; Wen, Shi-Bo +2 more
We carry out an optical morphological and infrared spectral study for two young planetary nebulae (PNs) Hen 2-158 and Pe 1-1 to understand their complex shapes and dust properties. Hubble Space Telescope optical images reveal that these nebulae have several bipolar-lobed structures and a faint arc with a clear boundary is located at the northweste…
Parámetros astrofísicos de cúmulos abiertos ubicados en el tercer y cuarto cuadrante de la Galaxia
Baracchi, M. A.; Colazo, A. D. V.; Rodríguez-Buss, C. M. +7 more
As part of new project in the framework of the activities of the subject `Astrofísica General} (FaMAF, UNC), we present astrophysical parameters of open clusters located in the third and fourth Galactic quadrant: NGC 2243, NGC 2439, Pi 12, Tr 13 and NGC 5168. Based on Gaia DR3 photometric data and fitting theoretical isochrones to the color-magnit…
The Nature of LoBAL QSOs. II. HST/WFC3 Observations Reveal Host Galaxies Dominated by Mergers
Lacy, Mark; Canalizo, Gabriela; Farrah, Duncan +4 more
Low-ionization broad absorption line QSOs (LoBALs) are suspected to be merging systems in which extreme, active galactic nucleus-driven outflows have been triggered. Whether or not LoBALs are uniquely associated with mergers, however, has yet to be established. To characterize the morphologies of LoBALs, we present the first high-resolution morpho…
TOI-2498 b: a hot bloated super-Neptune within the Neptune desert
Cegla, Heather M.; Latham, David W.; Fernández Fernández, Jorge +39 more
We present the discovery and confirmation of a transiting hot bloated super-Neptune using photometry from the Transiting Exoplanet Survey Satellite (TESS) and the Las Cumbres Observatory Global Telescope (LCOGT) and radial velocity measurements from the High Accuracy Radial velocity Planet Searcher (HARPS). The host star TOI-2498 is a V = 11.2, G-…