Search Publications
Detailed analysis of the variable star population in the globular cluster NGC 7006
Arellano Ferro, A.; Muneer, S.; Bustos Fierro, I. H. +3 more
A 5-yr CCD photometric VI time series of NGC 7006 is employed to perform a detailed analysis of the known population of variable stars. In the process, we have corrected inconsistent classifications, sky coordinates and found 10 new cluster member variables. An independent reddening estimate with a value E(B-V) = 0.08 ± 0.05 is made. Using Fourier…
Accelerating Multiframe Blind Deconvolution via Deep Learning
Asensio Ramos, Andrés; Kuckein, Christoph; Esteban Pozuelo, Sara
Ground-based solar-image restoration is a computationally expensive procedure that involves nonlinear optimization techniques. The presence of atmospheric turbulence produces perturbations in individual images that make it necessary to apply blind deconvolution techniques. These techniques rely on the observation of many short-exposure frames that…
The nature of 500 micron risers - II. Multiplicities and environments of sub-mm faint dusty star-forming galaxies
Pérez-Fournon, I.; Clements, D. L.; Riechers, D. +6 more
We present Submillimeter Common User Bolometer Array 2 (SCUBA-2) and Submillimeter Array (SMA) follow-up observations of four candidate high-redshift dusty star-forming galaxies, selected as sources with rising spectral energy distributions in the 250, 350, and 500 µm Herschel SPIRE bands. Previous SMA observations showed no counterparts to …
The M 101 galaxy group as a node in a nearby cosmic filament
Karachentsev, Igor D.; Karachentseva, Valentina E.; Kaisina, Elena I. +1 more
We performed a search for faint low-surface-brightness dwarf galaxies around the major spiral galaxy M 101 and in the large rectangular area within SGL = [30-80]° and SGB = [10-37]° spanning a chain of galaxies: M 63, M 51, M 101, and NGC 6503. We based our search on data from DESI Legacy Imaging Surveys. We discovered six new probable dwarf membe…
Angular Momentum Variation of the Milky Way Thick Disk: The Dependence of Chemical Abundance and Evidence of the Inside-out Formation Scenario
Li, Lu; Hu, Guozhen; Shao, Zhengyi
We investigate the angular momentum of mono-abundance populations (MAPs) of the Milky Way thick disk by using a sample of 26,076 giant stars taken from APOGEE Data Release (DR) 17 and Gaia early DR3. The vertical and perpendicular angular momentum components, L Z and L P , of the MAPs in narrow bins have significant variat…
Stellar halo striations from assumptions of axisymmetry
Belokurov, Vasily; Evans, N. Wyn; Davies, Elliot Y. +1 more
Motivated by the Large Magellanic Cloud (LMC)'s impact on the integral of motion space of the stellar halo, we run an N-body merger simulation to produce a population of halo-like stars. We subsequently move to a test-particle simulation, in which the LMC perturbs this debris. When an axisymmetric potential is assumed for the final snapshot of the…
Searching for the Role of Mergers in Fast and Early SMBH Growth: Morphological Decomposition of Quasars and Their Hosts at z 4.8
Trakhtenbrot, Benny; Simmons, Brooke D.; Netzer, Hagai +4 more
We present rest-frame ultraviolet images of six luminous quasars at z ~ 4.8 obtained with the Hubble Space Telescope (HST). These quasars exhibit a wide range of star formation rates (SFRs) and lie in a wide range of environments. We carefully model and subtract the point-like quasar emission and investigate the morphology of the underlying host g…
The Return of the Rosetta Target: Keck Near-infrared Observations of Comet 67P/Churyumov-Gerasimenko in 2021
Ootsubo, Takafumi; Villanueva, Geronimo L.; Cochran, Anita L. +20 more
High-resolution near-infrared ground-based spectroscopic observations of comet 67P/Churyumov-Gerasimenko near its maximum activity in 2021 were conducted from the W. M. Keck Observatory, using the facility spectrograph NIRSPEC. 67P is the best-studied comet to date because of the unprecedented detail and insights provided by the Rosetta mission du…
Hubble Space Telescope imaging of the compact elliptical galaxy M32 reveals a dearth of carbon stars
Boyer, M. L.; Meixner, M.; van Loon, J. Th +2 more
We present new Hubble Space Telescope Wide-Field Camera 3/infrared medium-band photometry of the compact elliptical galaxy M32, chemically resolving its thermally pulsating asymptotic giant branch stars. We find 2829 M-type stars and 57 C stars. The carbon stars are likely contaminants from M31. If carbon stars are present in M32 they are so in ve…
A 600 kpc complex radio source at the center of Abell 3718 discovered by the EMU and POSSUM surveys
Filipović, M. D.; Lovisari, L.; Boschin, W. +10 more
Context. Multifrequency studies of galaxy clusters are crucial for inferring their dynamical states and physics. Moreover, these studies allow us to investigate cluster-embedded sources, whose evolution is affected by the physical and dynamical condition of the cluster itself. So far, these kinds of studies have been preferentially conducted on cl…