Search Publications
Investigation of the M13 Globular Cluster: Characteristics and Pulsation Periods of Its RR Lyrae Stars V8, V31, and V54
Wang, J.; Lee, K.; Tock, K. +2 more
Images of the Messier 13 (M13/NGC 6205) globular cluster were requested from the Las Cumbres Global Observatory's 40-centimeter telescope to investigate the chemical composition and characteristics of the cluster along with three of its RR Lyrae variable stars. Gaia Data Release 3 data were used to fit an isochrone by varying parameters such as di…
Evolutionary map of the universe (EMU): Observations of filamentary structures in the Abell S1136 galaxy cluster
Reiprich, Thomas H.; Koribalski, Bärbel S.; Norris, Ray P. +17 more
We present radio observations of the galaxy cluster Abell S1136 at 888 MHz, using the Australian Square Kilometre Array Pathfinder radio telescope, as part of the Evolutionary Map of the Universe Early Science program. We compare these findings with data from the Murchison Widefield Array, XMM-Newton, the Wide-field Infrared Survey Explorer, the D…
A search for Galactic post-asymptotic giant branch stars in Gaia DR3
Dafonte, C.; González-Santamaría, I.; Manteiga, M. +3 more
Context. When low- and intermediate-mass stars leave the asymptotic giant branch (AGB) phase, and before they reach the planetary nebula stage, they enter a very brief and rather puzzling stellar evolutionary stage called post-AGB stage. The post-AGB phase lasts very briefly, about a few thousand years at most. The number of objects that are confi…
The Redshift of GRB 190829A/SN 2019oyw: A Case Study of GRB-SN Evolution
Fruchter, Andrew S.; Izzo, Luca; Tanvir, Nial +7 more
The nearby long gamma-ray burst (GRB) 190829A was observed using the Hubble Space Telescope/Wide Field Camera 3/infrared grisms about four weeks to 500 days after the burst. We find the spectral features of its associated supernova, SN 2019oyw, are redshifted by several thousand km s‑1 compared to the redshift of the large spiral galaxy…
Seasonal low albedo streaks at the edge of the Martian south polar layered deposits
Lucchetti, Alice; Pajola, Maurizio; Cremonese, Gabriele +6 more
Low Albedo Streaks (LAS) are narrow dark streaks observed at the edges of the South Polar Layered Deposits (SPLD) on Mars. We investigate the seasonal morphology, surface topography of LAS-rich areas using monochrome and multiband images from both the High Resolution Imaging Science Experiment (HiRISE) and the Color and Stereo Surface Imaging Syst…
Possible Supercritical Accretion on the Ultraluminous X-Ray Source in the Metal-poor Galaxy I Zw 18
Yoneyama, Tomokage; Matsumoto, Hironori; Noda, Hirofumi +2 more
We present an analysis of X-ray observations of the ultraluminous X-ray source (ULX) in I Zw 18 based on archival data taken with Chandra, XMM-Newton, and Suzaku. This ULX is considered to be an intermediate-mass black hole candidate simply because it is in the lowest-metallicity environment among ULXs, where the formation of heavy black holes is …
Deep Hard X-ray Survey of the M81 Field Based on INTEGRAL1 Data
Sazonov, S. Yu.; Mereminskiy, I. A.; Krivonos, R. A.
We have carried out a deep survey of the M81 field in the 25-60 keV energy band based on long-term (2003-2023) INTEGRAL observations. A record sensitivity of 0.16 mCrab at a detection significance of $4σ$ has been achieved in the central part of the field owing to the long accumulated exposure (19.2 Ms). The total area of the survey is 1004 deg${}…
Orbits and Dynamical Masses for Six Binary Systems in the Hyades Cluster
Torres, Guillermo; Latham, David W.; Klement, Robert +8 more
We report long-baseline interferometric observations with the CHARA Array that resolve six previously known double-lined spectroscopic binary systems in the Hyades cluster, with orbital periods ranging from 3 to 358 days: HD 27483, HD 283882, HD 26874, HD 27149, HD 30676, and HD 28545. We combine those observations with new and existing radial-vel…
Chemical composition of planetary hosts: C, N, and α-element abundances
Tautvaišienė, G.; Mikolaitis, Š.; Minkevičiūtė, R. +4 more
Context. Accurate atmospheric parameters and chemical composition of planet hosts play a major role in characterising exoplanets and understanding their formation and evolution. Aims. Our objective is to uniformly determine atmospheric parameters and chemical abundances of carbon (C), nitrogen (N), oxygen(O), and the α-elements, magnesium (Mg) and…
Broad-Band X-Ray Analysis of NGC 3227
Newman, Jared; Tsuruta, Sachiko; Liebmann, Andrew C. +2 more
Previously in Project A we carried out analysis of the data obtained by observations of the 1.5 Seyfert galaxy NGC 3227-the two observations performed by XMM-Newton in 2000 and 2006 and six observations by Suzaku in 2008. In the current paper, Project B, our work was extended to joint XMM-Newton and NuSTAR observations in 2016 as well as a NuSTAR …