Search Publications

Properties of Solar Rossby Waves from Normal Mode Coupling and Characterizing Its Systematics
DOI: 10.3847/1538-4357/ab7227 Bibcode: 2020ApJ...891..125M

Mandal, Krishnendu; Hanasoge, Shravan

Rossby waves play an important role in mediating the angular momentum of rotating spherical fluids, creating weather on Earth and tuning exoplanet orbits in distant stellar systems. Their recent discovery in the solar convection zone provides an exciting opportunity to appreciate the detailed astrophysics of Rossby waves. Large-scale Rossby waves …

2020 The Astrophysical Journal
SOHO 26
The GTC exoplanet transit spectroscopy survey. XI. Possible detection of Rayleigh scattering in the atmosphere of the Saturn-mass planet WASP-69b
DOI: 10.1051/0004-6361/202038161 Bibcode: 2020A&A...641A.158M

Nortmann, L.; Palle, E.; Nowak, G. +2 more

Context. One of the main atmospheric features in exoplanet atmospheres, detectable both from ground- and space-based facilities, is Rayleigh scattering. In hydrogen-dominated planetary atmospheres, Rayleigh scattering causes the measured planetary radius to increase toward blue wavelengths in the optical range.
Aims: We aim to detect and impr…

2020 Astronomy and Astrophysics
eHST 26
Unlocking Galactic Wolf-Rayet stars with Gaia DR2 - II. Cluster and association membership
DOI: 10.1093/mnras/staa1290 Bibcode: 2020MNRAS.495.1209R

Parker, Richard J.; Crowther, Paul A.; Rate, Gemma

Galactic Wolf-Rayet (WR) star membership of star-forming regions can be used to constrain the formation environments of massive stars. Here, we utilize Gaia DR2 parallaxes and proper motions to reconsider WR star membership of clusters and associations in the Galactic disc, supplemented by recent near-infrared studies of young massive clusters. We…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 26
The Cluster AgeS Experiment (CASE) - VIII. Age and distance of the Globular Cluster 47 Tuc from the analysis of two detached eclipsing binaries
DOI: 10.1093/mnras/staa032 Bibcode: 2020MNRAS.492.4254T

Soszyński, I.; Udalski, A.; Szymański, M. K. +20 more

We use photometric and spectroscopic observations of the eclipsing binary E32 in the globular cluster 47 Tuc to derive the masses, radii, and luminosities of the component stars. The system has an orbital period of 40.9 d, a markedly eccentric orbit with e = 0.24, and is shown to be a member of or a recent escaper from the cluster. We obtain M_p =…

2020 Monthly Notices of the Royal Astronomical Society
Gaia eHST 26
The first broad-band X-ray view of the narrow-line Seyfert 1 Ton S180
DOI: 10.1093/mnras/staa2076 Bibcode: 2020MNRAS.497.2352M

Ebrero, J.; Schartel, N.; Santos-Lleó, M. +15 more

We present joint XMM-Newton and NuSTAR observations of the 'bare' narrow-line Seyfert 1 Ton S180 (z = 0.062), carried out in 2016 and providing the first hard X-ray view of this luminous galaxy. We find that the 0.4-30 keV band cannot be self-consistently reproduced by relativistic reflection models, which fail to account simultaneously for the so…

2020 Monthly Notices of the Royal Astronomical Society
XMM-Newton 26
A DECam view of the diffuse dwarf galaxy Crater II - Variable stars
DOI: 10.1093/mnras/stz3393 Bibcode: 2020MNRAS.492.1061V

Nidever, David L.; Olsen, Knut; Walker, Alistair R. +11 more

Time series observations of a single dithered field centred on the diffuse dwarf satellite galaxy Crater II were obtained with the Dark Energy Camera (DECam) at the 4m Blanco Telescope at Cerro Tololo Inter-American Observatory, Chile, uniformly covering up to two half-light radii. Analysis of the g and I time series results in the identification …

2020 Monthly Notices of the Royal Astronomical Society
Gaia 26
Infalling gas in a Lyman-α blob
DOI: 10.1038/s41550-020-1033-3 Bibcode: 2020NatAs...4..670A

Kohno, Kotaro; Lehnert, Matthew D.; Menten, Karl M. +11 more

Lyman-α blobs (LABs) are spatially extended nebulae of emission in the Lyman-α (Lyα) line of hydrogen, seen at high redshifts1,2, and most commonly found in the dense environment of star-forming galaxies3,4. A recent study showed that nearly 100% of the sky is covered by Lyα emission around high-redshift galaxies5-7

2020 Nature Astronomy
Herschel 26
Orbital and spectral characterization of the benchmark T-type brown dwarf HD 19467B
DOI: 10.1051/0004-6361/202037984 Bibcode: 2020A&A...639A..47M

Henning, T.; Brandner, W.; Ségransan, D. +42 more

Context. Detecting and characterizing substellar companions for which the luminosity, mass, and age can be determined independently is of utter importance to test and calibrate the evolutionary models due to uncertainties in their formation mechanisms. HD 19467 is a bright and nearby star hosting a cool brown dwarf companion detected with radial v…

2020 Astronomy and Astrophysics
Gaia Hipparcos 26
Physical Characterization of Interstellar Comet 2I/2019 Q4 (Borisov)
DOI: 10.3847/1538-3881/ab9df8 Bibcode: 2020AJ....160...92H

Tholen, David J.; Ye, Quan-Zhi; Hui, Man-To +2 more

We present a study of interstellar comet 2I/2019 Q4 (Borisov) using both preperihelion and postperihelion observations spanning late September 2019 through late January 2020. The intrinsic brightness of the comet was observed to continuously decline throughout the timespan, likely due to the decreasing effective scattering cross-section as a resul…

2020 The Astronomical Journal
Gaia 26
Charge induced acceleration noise in the LISA gravitational reference sensor
DOI: 10.1088/1361-6382/ab5f6e Bibcode: 2020CQGra..37d5010S

Sumner, Timothy J.; Wass, Peter J.; Conklin, John W. +2 more

The presence of free charge on isolated proof-masses, such as those within space-borne gravitational reference sensors, causes a number of spurious forces which will give rise to associated acceleration noise. A complete discusssion of each charge induced force and its linear acceleration noise is presented. The resulting charge acceleration noise…

2020 Classical and Quantum Gravity
LISAPathfinder 26