Search Publications

Characterizing the companion AGBs using surface chemical composition of barium stars
DOI: 10.1093/mnras/stz3518 Bibcode: 2020MNRAS.492.3708S

Masseron, Thomas; Shejeelammal, J.; Goswami, Aruna +2 more

Barium stars are one of the important probes to understand the origin and evolution of slow neutron-capture process elements in the Galaxy. These are extrinsic stars, where the observed s-process element abundances are believed to have an origin in the now invisible companions that produced these elements at their asymptotic giant branch (AGB) pha…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 23
Structure of the outer Galactic disc with Gaia DR2
DOI: 10.1051/0004-6361/201937289 Bibcode: 2020A&A...637A..96C

López-Corredoira, M.; Chrobáková, Ž.; Nagy, R.

Context. The structure of outer disc of our Galaxy is still not well described, and many features need to be better understood. The second Gaia data release (DR2) provides data in unprecedented quality that can be analysed to shed some light on the outermost parts of the Milky Way.
Aims: We calculate the stellar density using star counts obta…

2020 Astronomy and Astrophysics
Gaia 23
Dependence of the IRX-β Dust Attenuation Relation on Metallicity and Environment
DOI: 10.3847/2041-8213/abc1ef Bibcode: 2020ApJ...903L..28S

Shivaei, Irene; Mobasher, Bahram; Scoville, Nick +4 more

We use a sample of star-forming field and protocluster galaxies at z = 2.0-2.5 with Keck/MOSFIRE K-band spectra, a wealth of rest-frame ultraviolet (UV) photometry, and Spitzer/MIPS and Herschel/PACS observations, to dissect the relation between the ratio of infrared (IR) to UV luminosity (IRX) versus UV slope (β) as a function of gas-phase metall…

2020 The Astrophysical Journal
Herschel 23
NIR counterparts to ULXs (III): completing the photometric survey and selected spectroscopic results
DOI: 10.1093/mnras/staa1920 Bibcode: 2020MNRAS.497..917L

Harrison, F. A.; Roberts, T. P.; Torres, M. A. P. +5 more

We present results from the remaining sources in our search for near-infrared (NIR) candidate counterparts to ultraluminous X-ray sources (ULXs) within ≃10 Mpc. We observed 23 ULXs in 15 galaxies and detected NIR candidate counterparts to 6 of them. Two of these have an absolute magnitude consistent with a single red supergiant (RSG). Three counte…

2020 Monthly Notices of the Royal Astronomical Society
Gaia eHST 23
A parsec-scale radio jet launched by the central intermediate-mass black hole in the dwarf galaxy SDSS J090613.77+561015.2
DOI: 10.1093/mnrasl/slaa052 Bibcode: 2020MNRAS.495L..71Y

Paragi, Zsolt; Frey, Sándor; Yang, Jun +4 more

The population of intermediate-mass black holes (IMBHs) in nearby dwarf galaxies plays an important 'ground truth' role in exploring black hole formation and growth in the early Universe. In the dwarf elliptical galaxy SDSS J090613.77+561015.2 (z = 0.0465), an accreting IMBH has been revealed by optical and X-ray observations. Aiming to search for…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 23
A Massive Molecular Torus inside a Gas-poor Circumnuclear Disk in the Radio Galaxy NGC 1052 Discovered with ALMA
DOI: 10.3847/1538-4357/ab8bd6 Bibcode: 2020ApJ...895...73K

Kohno, Kotaro; Terashima, Yuichi; Nakai, Naomasa +7 more

We report ALMA observations of NGC 1052 to search for mass accretion in a gas-poor active galactic nucleus. We detected CO emission representing a rotating ring-like circumnuclear disk (CND) seen edge-on with a gas mass of 5.3 × 105 M. The CND has smaller gas mass than that in typical Seyfert galaxies with circumnuclear star…

2020 The Astrophysical Journal
eHST 23
Power spectra of solar brightness variations at various inclinations
DOI: 10.1051/0004-6361/202037588 Bibcode: 2020A&A...636A..43N

Solanki, S. K.; Shapiro, A. I.; Tagirov, R. V. +4 more

Context. Magnetic features on the surfaces of cool stars lead to variations in their brightness. Such variations on the surface of the Sun have been studied extensively. Recent planet-hunting space telescopes have made it possible to measure brightness variations in hundred thousands of other stars. The new data may undermine the validity of setti…

2020 Astronomy and Astrophysics
SOHO 23
Seasonal changes in the middle atmosphere of Titan from Cassini/CIRS observations: Temperature and trace species abundance profiles from 2004 to 2017
DOI: 10.1016/j.icarus.2019.113547 Bibcode: 2020Icar..34413547M

Bézard, Bruno; Vinatier, Sandrine; Jennings, Donald E. +6 more

The Cassini/Composite InfraRed Spectrometer (CIRS) instrument has been observing the middle atmosphere of Titan over almost half a Saturnian year. We used the CIRS dataset processed through the up-to-date calibration pipeline to characterize seasonal changes of temperature and abundance profiles in the middle atmosphere of Titan, from mid-northern…

2020 Icarus
Cassini 23
Discovery of a soft X-ray lag in the ultraluminous X-ray source NGC 1313 X-1
DOI: 10.1093/mnras/stz3318 Bibcode: 2020MNRAS.491.5172K

Fabian, A. C.; Pinto, C.; Bachetti, M. +14 more

Ultraluminous X-ray sources (ULXs) provide a unique opportunity to probe the geometry and energetics of super-Eddington accretion. The radiative processes involved in super-Eddington accretion are not well understood, and so studying correlated variability between different energy bands can provide insights into the causal connection between diffe…

2020 Monthly Notices of the Royal Astronomical Society
XMM-Newton 23
Cosmological insights into the assembly of the radial and compact stellar halo of the Milky Way
DOI: 10.1093/mnras/staa1090 Bibcode: 2020MNRAS.495...29E

Hernquist, Lars; Helmi, Amina; Sales, Laura V. +1 more

Recent studies using Gaia DR2 have identified a massive merger in the early history of the Milky Way (MW) whose debris is dominated by radial and counterrotating orbits. This event, dubbed the Gaia-Enceladus/Gaia-Sausage (GE/GS), is also hypothesized to have built the majority of the inner stellar halo. We use the cosmological hydrodynamic simulat…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 23