Search Publications
Missions
Journals
Publication Years
UVIT Study of the MAgellanic Clouds (U-SMAC) - I. Recent star formation history and kinematics of the Shell region in the north-eastern Small Magellanic Cloud
Cioni, Maria-Rosa L.; Subramaniam, Annapurni; Subramanian, Smitha +2 more
The interactions between the Magellanic Clouds significantly affect the shape and distribution of the young stellar population, particularly in the periphery of the Small Magellanic Cloud (SMC). We present the first far-UV (FUV) map of the north-east SMC-Shell region using the Ultra Violet Imaging Telescope (UVIT) onboard AstroSat. The detected FU…
Revealing the state transition of Cen X-3 at high spectral resolution with Chandra
Torrejón, J. M.; Postnov, K.; Nowak, M. +4 more
Cen X-3 is a compact, high-mass X-ray binary (HMXRB), likely powered by Roche lobe overflow. We present a phase-resolved X-ray spectral and timing analysis of a target of opportunity Chandra observation made during a low-flux to high-flux transition. The high-resolution spectra allow us to delve into the events that occurred during this episode. T…
A comprehensive X-ray analysis of the massive O-type binary HD 93250 over two decades
De Becker, Michaël; Arora, Bharti; Pandey, Jeewan C.
Context. Massive star winds are known to be responsible for X-ray emission arising from wind plasma heated by the strong shocks up to temperatures of 106-107 K in the case of colliding wind binaries. The investigation of X-ray emission from massive stars thus constitutes a valuable tool for identifying binaries, which is othe…
Observational clues to the magnetic evolution of magnetars
Enoto, Teruaki; Makishima, Kazuo; Uchida, Nagomi
Utilizing four archival X-ray data sets taken with the Hard X-ray Detector onboard Suzaku, timing studies were performed on three magnetars, 1E 1841-045 (observed in 2006), SGR 0501+4516 (2008), and 1RXS J170849.0-400910 (2009 and 2010). Their pulsations were reconfirmed, typically in an energy range of 12-50 keV. The 11.783 s pulses of 1E 1841-04…
Wide binaries and modified gravity (MOG)
Moffat, J. W.
Wide binary stars are used to test the modified gravity called Scalar-Tensor-Vector Gravity or MOG. This theory is based on the additional gravitational degrees of freedom, the scalar field G = GN (1+α), where GN is Newton's constant, and the massive (spin-1 graviton) vector field ϕµ . The wide binaries have …
Multi-Spacecraft Magnetic Field Reconstructions: A Cross-Scale Comparison of Methods
Klein, K. G.; Broeren, T.; TenBarge, J. M.
Space plasma studies frequently use in situ magnetic field measurements taken from many spacecraft simultaneously. A useful data product of these measurements is the reconstructed magnetic field in a volume near the spacecraft observatory. We compare a standard Linear method of computing the magnetic field at arbitrary spatial points to two novel …
Identification of a single plasma parcel during a radial alignment of the Parker Solar Probe and Solar Orbiter
Alexandrova, Olga; Maksimovic, Milan; Démoulin, Pascal +2 more
Configurations in which two spacecraft, such as the Parker Solar Probe (PSP) and Solar Orbiter, are radially aligned provide opportunities for studying the evolution of a single solar wind parcel during so-called plasma line-ups. The most critical part of these studies arguably is the identification of what can be considered the same plasma crossi…
Asteroseismic Inversions for Internal Sound Speed Profiles of Main-sequence Stars with Radiative Cores
Basu, Sarbani; Hekker, Saskia; Christensen-Dalsgaard, Jørgen +3 more
The theoretical oscillation frequencies of even the best asteroseismic models of solar-like oscillators show significant differences from observed oscillation frequencies. Structure inversions seek to use these frequency differences to infer the underlying differences in stellar structure. While used extensively to study the Sun, structure inversi…
Chandra X-Ray Observatory Observations of 13 Fermi LAT Sources
Kargaltsev, Oleg; Yang, Hui; Hare, Jeremy +3 more
In the latest data release from the Fermi Gamma-ray Space Telescope (the 4th Fermi LAT 14 yr Catalog, or 4FGL), more than 50% of the Galactic sources are yet to be identified. We observed 13 unidentified Fermi LAT sources with the Chandra X-Ray Observatory to explore their nature. We report the results of the classification of X-ray sources in the…
PLATO on the shoulders of TESS: analysing mono-transit planet candidates in TESS data as a prior knowledge for PLATO observations
Vines, Jose I.; Piotto, Giampaolo; Kostov, Veselin +9 more
The Transiting Exoplanet Survey Satellite (TESS) and the upcoming mission PLAnetary Transits and Oscillations of stars (PLATO) represent two space-based missions with complementary objectives in the field of exoplanet science. While TESS aims at detecting and characterizing exoplanets around bright and nearby stars on a relative short-period orbit…