Search Publications

A Catalog of M-dwarf Flares with ASAS-SN
DOI: 10.3847/1538-4357/ab793a Bibcode: 2020ApJ...892..144R

Holoien, Thomas W. -S.; Auchettl, Katie; Kochanek, Christopher S. +5 more

We analyzed the light curves of 1376 early-to-late, nearby M dwarfs to search for white-light flares using photometry from the All-Sky Automated Survey for Supernovae. We identified 480 M dwarfs with at least one potential flare employing a simple statistical algorithm that searches for sudden increases in V-band flux. After more detailed evaluati…

2020 The Astrophysical Journal
Gaia 41
First direct observation of a torsional Alfvén oscillation at coronal heights
DOI: 10.1051/0004-6361/201937144 Bibcode: 2020A&A...633L...6K

Kohutova, P.; Verwichte, E.; Froment, C.

Context. Torsional Alfvén waves are promising candidates for the transport of energy across different layers of the solar atmosphere. They have been predicted theoretically for decades. Previous detections of Alfvén waves so far have however mostly relied on indirect signatures.
Aims: We present the first direct observational evidence of a fu…

2020 Astronomy and Astrophysics
IRIS 40
Dissecting the Phase Space Snail Shell
DOI: 10.3847/1538-4357/ab6b21 Bibcode: 2020ApJ...890...85L

Shen, Juntai; Li, Zhao-Yu

The ongoing vertical phase-mixing, manifesting itself as a snail shell in the $Z-{V}_{Z}$ phase space, has been discovered with Gaia DR2 data. To better understand the origin and properties of the phase-mixing process, we study the vertical phase-mixing signatures in arches (including the classical "moving groups") of the ${V}_{R}-{V}_{\phi }$ pha…

2020 The Astrophysical Journal
Gaia 40
AstroSat detection of Lyman continuum emission from a z = 1.42 galaxy
DOI: 10.1038/s41550-020-1173-5 Bibcode: 2020NatAs...4.1185S

Verhamme, Anne; Inoue, Akio K.; Schaerer, Daniel +10 more

One of the outstanding problems of current observational cosmology is to understand the nature of sources that produced the bulk of the ionizing radiation after the Cosmic Dark Age. Direct detection of these reionization sources1 is practically infeasible at high redshift (z) due to the steep decline of intergalactic medium transmission…

2020 Nature Astronomy
eHST 40
Scalable end-to-end recurrent neural network for variable star classification
DOI: 10.1093/mnras/staa350 Bibcode: 2020MNRAS.493.2981B

Catelan, M.; Nikzat, F.; Protopapas, P. +3 more

During the last decade, considerable effort has been made to perform automatic classification of variable stars using machine-learning techniques. Traditionally, light curves are represented as a vector of descriptors or features used as input for many algorithms. Some features are computationally expensive, cannot be updated quickly and hence for…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 40
Web of the giant: Spectroscopic confirmation of a large-scale structure around the z = 6.31 quasar SDSS J1030+0524
DOI: 10.1051/0004-6361/202039045 Bibcode: 2020A&A...642L...1M

Comastri, Andrea; Zamorani, Giovanni; Vito, Fabio +14 more

We report on the spectroscopic confirmation of a large-scale structure around the luminous z = 6.31 quasi-stellar object (QSO) SDSS J1030+0524, powered by a one billion solar mass black hole. The structure is populated by at least six members, namely, four Lyman-break galaxies (LBGs), and two Lyman alpha emitters (LAEs). The four LBGs were identif…

2020 Astronomy and Astrophysics
eHST 40
Shapes and alignments of dark matter haloes and their brightest cluster galaxies in 39 strong lensing clusters
DOI: 10.1093/mnras/staa1479 Bibcode: 2020MNRAS.496.2591O

Oguri, Masamune; Suto, Yasushi; Kitayama, Tetsu +6 more

We study shapes and alignments of 45 dark matter (DM) haloes and their brightest cluster galaxies (BCGs) using a sample of 39 massive clusters from Hubble Frontier Field (HFF), Cluster Lensing And Supernova survey with Hubble (CLASH), and Reionization Lensing Cluster Survey (RELICS). We measure shapes of the DM haloes by strong gravitational lensi…

2020 Monthly Notices of the Royal Astronomical Society
eHST 40
Pressure Profiles and Mass Estimates Using High-resolution Sunyaev-Zel'dovich Effect Observations of Zwicky 3146 with MUSTANG-2
DOI: 10.3847/1538-4357/ab6d70 Bibcode: 2020ApJ...891...90R

Battaglia, Nicholas; Mroczkowski, Tony; Devlin, Mark +12 more

The galaxy cluster Zwicky 3146 is a sloshing cool core cluster at z = 0.291 that in X-ray imaging does not appear to exhibit significant pressure substructure in the intracluster medium (ICM). The published M500 values range between 3.88-0.58+0.62 to (22.50 ± 7.58) × 1014 M, where ICM-based e…

2020 The Astrophysical Journal
XMM-Newton 40
Fundamental stellar parameters of benchmark stars from CHARA interferometry. I. Metal-poor stars
DOI: 10.1051/0004-6361/202037590 Bibcode: 2020A&A...640A..25K

White, T. R.; Casagrande, L.; Jofré, P. +4 more

Context. Benchmark stars are crucial as validating standards for current as well as future large stellar surveys of the Milky Way. However, the number of suitable metal-poor benchmark stars is currently limited, owing to the difficulty in determining reliable effective temperatures (Teff) in this regime.
Aims: We aim to construct a…

2020 Astronomy and Astrophysics
Gaia 40
Consistently Simulating a Wide Range of Atmospheric Scenarios for K2-18b with a Flexible Radiative Transfer Module
DOI: 10.3847/1538-4357/ab9084 Bibcode: 2020ApJ...898...44S

Rauer, H.; Kappel, D.; Herbst, K. +6 more

The atmospheres of small, potentially rocky exoplanets are expected to cover a diverse range in composition and mass. Studying such objects therefore requires flexible and wide-ranging modeling capabilities. We present in this work the essential development steps that lead to our flexible radiative transfer module, REDFOX, and validate REDFOX for …

2020 The Astrophysical Journal
eHST 40