Search Publications

Milky Way Subsystems from Globular Cluster Kinematics Using Gaia DR2 and HST Data
DOI: 10.3847/1538-4357/ab8ea7 Bibcode: 2020ApJ...895...69B

Bobylev, V. V.; Bajkova, A. T.; Carraro, G. +2 more

We employ Gaia DR2 proper motions for 151 Milky Way globular clusters (GCs) from Vasiliev in tandem with distances and line-of-sight velocities to derive their kinematical properties. To assign clusters to the Milky Way thick disk, bulge, and halo, we follow the approach of Posti et al., who distinguished among different Galactic stellar component…

2020 The Astrophysical Journal
Gaia eHST 21
Investigating the magnetospheric accretion process in the young pre-transitional disk system DoAr 44 (V2062 Oph). A multiwavelength interferometric, spectropolarimetric, and photometric observing campaign
DOI: 10.1051/0004-6361/202038892 Bibcode: 2020A&A...643A..99B

Moutou, C.; Bayo, A.; Donati, J. -F. +13 more

Context. Young stars interact with their accretion disk through their strong magnetosphere.
Aims: We aim to investigate the magnetospheric accretion/ejection process in the young stellar system DoAr 44 (V2062 Oph).
Methods: We monitored the system over several rotational cycles, combining high-resolution spectropolarimetry at both optica…

2020 Astronomy and Astrophysics
Gaia 21
Modelling X-ray RMS spectra I: intrinsically variable AGNs
DOI: 10.1093/mnras/stz3470 Bibcode: 2020MNRAS.492.1363P

Fabian, A. C.; Alston, W. N.; Parker, M. L. +1 more

We present simple XSPEC models for fitting excess variance spectra of active galactic nuclei. Using a simple Monte Carlo approach, we simulate a range of spectra corresponding to physical parameters varying, then calculate the resulting variance spectra. Starting from a variable power law, we build up a set of models corresponding to the different…

2020 Monthly Notices of the Royal Astronomical Society
XMM-Newton 21
Implications of the Gaia sausage for dark matter nuclear interactions
DOI: 10.1103/PhysRevD.101.063026 Bibcode: 2020PhRvD.101f3026B

Buch, Jatan; Leung, John Shing Chau; Fan, JiJi

The advent of the Gaia era has led to potentially revolutionary understanding of dark matter (DM) dynamics in our galaxy, which has important consequences for direct detection (DD) experiments. In this paper, we study how the empirical DM velocity distribution inferred from Gaia-sausage, a dominant substructure in the solar neighborhood, affects t…

2020 Physical Review D
Gaia 21
A Catalog of RV Variable Star Candidates from LAMOST
DOI: 10.3847/1538-4365/ab9904 Bibcode: 2020ApJS..249...22T

Liu, Gaochao; Wu, Yaqian; Xiang, Maosheng +14 more

Radial velocity (RV) variable stars are important in astrophysics. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectroscopic survey has provided ∼6.5 million stellar spectra in its Data Release 4 (DR4). During the survey ∼4.7 million unique sources were targeted and ∼1 million stars observed repeatedly. The probabilities…

2020 The Astrophysical Journal Supplement Series
Gaia 21
Turbulence and Energetic Particles in Radiative Shock Waves in the Cygnus Loop. I. Shock Properties
DOI: 10.3847/1538-4357/ab886d Bibcode: 2020ApJ...894..108R

Blair, William P.; Slavin, Jonathan D.; Raymond, John C. +3 more

We have obtained a contiguous set of long-slit spectra of a shock wave in the Cygnus Loop to investigate its structure, which is far from the morphology predicted by 1D models. Proper motions from Hubble Space Telescope images combined with the known distance to the Cygnus Loop provide an accurate shock speed. Earlier analyses of shock spectra est…

2020 The Astrophysical Journal
eHST 21
Recurring Homologous Solar Eruptions in NOAA AR 11429
DOI: 10.3847/1538-4357/abacbc Bibcode: 2020ApJ...901...40D

Zhang, Jie; Vemareddy, Panditi; Karna, Nishu +1 more

We present the study of three homologous solar eruptions from NOAA active region (AR) 11429 over four days. This large and complex AR is divided into two relatively simple subregions: northeast (NE) and southwest (SW). Recurrent eruptions occurred from the SW subregion over different evolutionary phases, which provided a unique opportunity to isol…

2020 The Astrophysical Journal
Hinode SOHO 21
Spectroscopic Constraints on the Buildup of Intracluster Light in the Coma Cluster
DOI: 10.3847/1538-4357/ab845c Bibcode: 2020ApJ...894...32G

van Dokkum, Pieter; Bizyaev, Dmitry; Pan, Kaike +14 more

The stellar content of the intracluster light (ICL) provides unique insight into the hierarchical assembly process of galaxy clusters. We present optical spectra of three ICL regions (µg ≈ 25.3-26.2 mag arcsec-2) in the Coma cluster, located between 100 and 180 kpc from their nearest brightest cluster galaxies (BCGs): N…

2020 The Astrophysical Journal
eHST 21
The spatial evolution of young massive clusters. II. Looking for imprints of star formation in NGC 2264 with Gaia DR2
DOI: 10.1051/0004-6361/201936935 Bibcode: 2020A&A...636A..80B

Hacar, Álvaro; Buckner, Anne S. M.; Khorrami, Zeinab +12 more

Context. Better understanding of star formation in clusters with high-mass stars requires rigorous dynamical and spatial analyses of star-forming regions.
Aims: We seek to demonstrate that "INDICATE" is a powerful spatial analysis tool which when combined with kinematic data from Gaia DR2 can be used to probe star formation history in a robus…

2020 Astronomy and Astrophysics
Gaia Herschel 21
Very wide companion fraction from Gaia DR2: A weak or no enhancement for hot Jupiter hosts, and a strong enhancement for contact binaries
DOI: 10.1093/mnras/staa2124 Bibcode: 2020MNRAS.497.2250H

Zakamska, Nadia L.; Schlaufman, Kevin C.; Hwang, Hsiang-Chih +1 more

There is an ongoing debate on whether hot Jupiter hosts are more likely to be found in wide binaries with separations of ≳100 AU. In this paper, we search for comoving, very wide companions with separations of 103-104 AU for hot Jupiter hosts and main-sequence contact binaries in Gaia DR2, and compare the very wide companion …

2020 Monthly Notices of the Royal Astronomical Society
Gaia 21