Search Publications

The evolution of rapid optical/X-ray timing correlations in the initial hard state of MAXI J1820+070
DOI: 10.1093/mnras/stab1531 Bibcode: 2021MNRAS.505.3452P

Dhillon, V. S.; Charles, P. A.; Misra, R. +11 more

We report on a multiepoch campaign of rapid optical/X-ray timing observations of the superbright 2018 outburst of MAXI J1820+070, a black hole low-mass X-ray binary system. The observations spanned 80 d in the initial hard state and were taken with NTT/ULTRACAM and GTC/HiPERCAM in the optical (usgsrsisz<…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 19
Variability, periodicity, and contact binaries in WISE
DOI: 10.1093/mnras/stab592 Bibcode: 2021MNRAS.503.3975P

Zakamska, Nadia L.; Chandra, Vedant; Hwang, Hsiang-Chih +2 more

The time-series component of Wide-field Infrared Survey Explorer (WISE) is a valuable resource for the study of variable objects. We present an analysis of an all-sky sample of ~450 000 AllWISE+NEOWISE infrared light curves of likely variables identified in AllWISE. By computing periodograms of all these sources, we identify ~56 000 periodic varia…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 19
Fomalhaut b could be massive and sculpting the narrow, eccentric debris disc, if in mean-motion resonance with it
DOI: 10.1093/mnras/stab760 Bibcode: 2021MNRAS.503.4767P

Booth, Mark; Krivov, Alexander V.; Faramaz, Virginie +4 more

The star Fomalhaut hosts a narrow, eccentric debris disc, plus a highly eccentric companion Fomalhaut b. It is often argued that Fomalhaut b cannot have significant mass, otherwise it would quickly perturb the disc. We show that material in internal mean-motion resonances with a massive, coplanar Fomalhaut b would actually be long-term stable, and…

2021 Monthly Notices of the Royal Astronomical Society
eHST 19
Multiwavelength Properties of Miras
DOI: 10.3847/1538-4365/ac1797 Bibcode: 2021ApJS..257...23I

Udalski, Andrzej; Szymański, Michał K.; Skowron, Jan +12 more

We comprehensively study the variability of Miras in the Large Magellanic Cloud by simultaneously analyzing light curves in 14 bands in the range of 0.5-24 µm. We model over 20 yr long, high-cadence I-band light curves collected by the Optical Gravitational Lensing Experiment (OGLE) and fit them to light curves collected in the remaining opt…

2021 The Astrophysical Journal Supplement Series
Gaia 19
Astro-COLIBRI-The COincidence LIBrary for Real-time Inquiry for Multimessenger Astrophysics
DOI: 10.3847/1538-4365/ac1517 Bibcode: 2021ApJS..256....5R

Becker Tjus, J.; Lefranc, V.; Schüssler, F. +4 more

Astro-COLIBRI is a novel tool that evaluates alerts of transient observations in real time, filters them by user-specified criteria, and puts them into their multiwavelength and multimessenger context. Through fast generation of an overview of persistent sources as well as transient events in the relevant phase space, Astro-COLIBRI contributes to …

2021 The Astrophysical Journal Supplement Series
INTEGRAL 19
Dating individual quasars with the He II proximity effect
DOI: 10.1093/mnras/stab1685 Bibcode: 2021MNRAS.505.5084W

Hennawi, Joseph F.; Worseck, Gábor; Prochaska, J. Xavier +2 more

Constraints on the time-scales of quasar activity are key to understanding the formation and growth of supermassive black holes (SMBHs), quasar triggering mechanisms, and possible feedback effects on their host galaxies. However, observational estimates of this so-called quasar lifetime are highly uncertain (tQ ~ 104-109…

2021 Monthly Notices of the Royal Astronomical Society
eHST 19
Formation of a Solar Filament by Magnetic Reconnection, Associated Chromospheric Evaporation, and Subsequent Coronal Condensation
DOI: 10.3847/2041-8213/ac31b6 Bibcode: 2021ApJ...921L..33Y

Yang, Bo; Yang, Jiayan; Bi, Yi +2 more

We present the first observation of a solar filament formed by magnetic reconnection, associated chromospheric evaporation, and subsequent coronal condensation. Driven by shearing motion during flux emergence, a sequential tether-cutting reconnection process occurred and resulted in an M1.3 confined flare accompanied by the formation of a sigmoid …

2021 The Astrophysical Journal
Hinode 19
Revealing Efficient Dust Formation at Low Metallicity in Extragalactic Carbon-rich Wolf-Rayet Binaries
DOI: 10.3847/1538-4357/abd8cd Bibcode: 2021ApJ...909..113L

Moffat, Anthony F. J.; Smith, Nathan; Bond, Howard E. +6 more

We present Spitzer/InfraRed Array Camera observations of dust formation from six extragalactic carbon-rich Wolf-Rayet (WC) binary candidates in low-metallicity (Z ≲ 0.65 Z) environments using multiepoch mid-infrared (IR) imaging data from the SPitzer InfraRed Intensive Transients Survey (SPIRITS). Optical follow-up spectroscopy of SPIR…

2021 The Astrophysical Journal
eHST 19
Carbon photochemical escape rates from the modern Mars atmosphere
DOI: 10.1016/j.icarus.2021.114371 Bibcode: 2021Icar..36014371L

Yelle, Roger V.; Lillis, Robert J.; Lo, Daniel Y. +1 more

We provide a comprehensive update of photochemical escape rates of atomic carbon from the present-day Martian atmosphere using a one-dimensional photochemical model and a Monte Carlo escape model. The photochemical model incorporates new results relevant to carbon photochemistry at Mars, including new cross sections for photodissociation of CO

2021 Icarus
SOHO 19
The probabilistic random forest applied to the selection of quasar candidates in the QUBRICS survey
DOI: 10.1093/mnras/stab1867 Bibcode: 2021MNRAS.506.2471G

Grazian, Andrea; Boutsia, Konstantina; Cupani, Guido +5 more

The number of known, bright (i < 18), high-redshift (z > 2.5) QSOs in the Southern hemisphere is considerably lower than the corresponding number in the Northern hemisphere due to the lack of multiwavelength surveys at δ < 0. Recent works, such as the QUBRICS survey, successfully identified new, high-redshift QSOs in the South by means of…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 19