Search Publications

A Search for Wandering Black Holes in the Milky Way with Gaia and DECaLS
DOI: 10.3847/1538-4357/ac0896 Bibcode: 2021ApJ...917...17G

Ting, Yuan-Sen; Strader, Jay; Greene, Jenny E. +6 more

We present a search for "hypercompact" star clusters in the Milky Way using a combination of Gaia and the Dark Energy Camera Legacy Survey (DECaLS). Such putative clusters, with sizes of ~1 pc and containing 500-5000 stars, are expected to remain bound to intermediate-mass black holes (MBH ≈ 103-105 M) …

2021 The Astrophysical Journal
Gaia 18
Upper limits on the escape fraction of ionizing radiation from galaxies at 2 ≲ z < 6
DOI: 10.1093/mnras/stab2615 Bibcode: 2021MNRAS.508.4443M

Ryan-Weber, E. V.; Rafelski, M.; Bassett, R. +3 more

In this work, we investigate upper limits on the global escape fraction of ionizing photons ($f_{\rm esc/global}^{\rm abs}$) from a sample of galaxies probed for Lyman-continuum (LyC) emission characterized as non-LyC and LyC leakers. We present a sample of nine clean non-contaminated (by low-redshift interlopers, CCD problems, and internal reflec…

2021 Monthly Notices of the Royal Astronomical Society
eHST 18
Configuration of the Earth's Magnetotail Current Sheet
DOI: 10.1029/2020GL092153 Bibcode: 2021GeoRL..4892153A

Lin, Yu; Zhang, Xiao-Jia; El-Alaoui, Mostafa +7 more

The spatial scale and intensity of Earth's magnetotail current sheet determine the magnetotail configuration, which is critical to one of the most energetically powerful phenomena in the Earth's magnetosphere, substorms. In the absence of statistical information about plasma currents, theories of the magnetotail current sheets were mostly based on…

2021 Geophysical Research Letters
Cluster 18
A Metallicity Study of F, G, K, and M Dwarfs in the Coma Berenices Open Cluster from the APOGEE Survey
DOI: 10.3847/1538-4357/abfdb5 Bibcode: 2021ApJ...917...11S

Cunha, Katia; Smith, Verne V.; Souto, Diogo

We present a study of metallicities in a sample of main-sequence stars with spectral types M, K, G, and F (Teff ~3200-6500K and log g ~ 4.3-5.0 dex) belonging to the solar neighborhood young open cluster Coma Berenices. Metallicities were determined using the high-resolution (R = λ/Δ λ ~ 22,500) NIR spectra (λ1.51-λ1.69 µm) of the…

2021 The Astrophysical Journal
Gaia 18
Activity of TRAPPIST-1 analog stars observed with TESS
DOI: 10.1051/0004-6361/202040098 Bibcode: 2021A&A...650A.138S

Pál, András; Moór, Attila; Vida, Krisztián +2 more

As more exoplanets are being discovered around ultracool dwarfs, understanding their magnetic activity and the implications for habitability is of prime importance. To find stellar flares and photometric signatures related to starspots, continuous monitoring is necessary, which can be achieved with spaceborne observatories such as the Transiting E…

2021 Astronomy and Astrophysics
Gaia 18
WISDOM project - VIII. Multiscale feedback cycles in the brightest cluster galaxy NGC 0708
DOI: 10.1093/mnras/stab793 Bibcode: 2021MNRAS.503.5179N

Williams, Thomas G.; Sarzi, Marc; Cappellari, Michele +8 more

We present high-resolution (synthesized beam size 0${_{.}^{\prime\prime}}$088 × 0${_{.}^{\prime\prime}}$083 or 25 × 23 pc2) Atacama Large Millimetre/submillimetre Array 12CO(2-1) line and 236 GHz continuum observations, as well as 5 GHz enhanced Multi-Element Radio Linked Interferometer Network (e-MERLIN) continuum observatio…

2021 Monthly Notices of the Royal Astronomical Society
eHST 18
In search of radio emission from exoplanets: GMRT observations of the binary system HD 41004
DOI: 10.1093/mnras/staa3565 Bibcode: 2021MNRAS.500.4818N

Henning, Thomas; Mathew, Blesson; Manoj, P. +6 more

This paper reports Giant Metrewave Radio Telescope (GMRT) observations of the binary system HD 41004 that are among the deepest images ever obtained at 150 and 400 MHz in the search for radio emission from exoplanets. The HD 41004 binary system consists of a K1 V primary star and an M2 V secondary; both stars are host to a massive planet or brown …

2021 Monthly Notices of the Royal Astronomical Society
Gaia 18
The Flare and Warp of the Young Stellar Disk Traced with LAMOST DR5 OB-type Stars
DOI: 10.3847/1538-4357/ac1e91 Bibcode: 2021ApJ...922...80Y

Tian, Hao; Liu, Chao; Zhang, Bo +9 more

We present an analysis of the spatial density structure for the outer disk from 8-14 kpc with the LAMOST DR5 13,534 OB-type stars and observe similar flaring on the north and south sides of the disk, implying that the flaring structure is symmetrical about the Galactic plane, for which the scale height at different Galactocentric distances is from…

2021 The Astrophysical Journal
Gaia 18
Constraining Saturn's Interior with Ring Seismology: Effects of Differential Rotation and Stable Stratification
DOI: 10.3847/PSJ/ac0e2a Bibcode: 2021PSJ.....2..198D

Fuller, Jim; Lai, Dong; Dewberry, Janosz W. +2 more

Normal mode oscillations in Saturn excite density and bending waves in the C ring, providing a valuable window into the planet's interior. Saturn's fundamental modes (f-modes) excite the majority of the observed waves, while gravito-inertial modes (rotationally modified g-modes) associated with stable stratification in the deep interior provide a …

2021 The Planetary Science Journal
Cassini 18
The outburst of a 60 min AM CVn reveals peculiar colour evolution: implications for outbursts in long-period double white dwarfs
DOI: 10.1093/mnras/stab1246 Bibcode: 2021MNRAS.505..215R

Maccarone, T. J.; Cavecchi, Y.; Rivera Sandoval, L. E. +2 more

We report on multiwavelength observations during quiescence and of the first detected outburst of the ≈60 min orbital period AM CVn SDSS J113732+405458. Using X-ray and UV observations, we determined an upper limit duration of the event of about 1 yr. The amplitude of the outburst was remarkably small, of around 1 mag in r and 0.5 mag in g. We hav…

2021 Monthly Notices of the Royal Astronomical Society
Gaia XMM-Newton 18