Search Publications

Microlensing Optical Depth and Event Rate toward the Galactic Bulge from 8 yr of OGLE-IV Observations
DOI: 10.3847/1538-4365/ab426b Bibcode: 2019ApJS..244...29M

Udalski, Andrzej; Mróz, Przemek; Szymański, Michał K. +9 more

The number and properties of observed gravitational microlensing events depend on the distribution and kinematics of stars and other compact objects along the line of sight. In particular, precise measurements of the microlensing optical depth and event rate toward the Galactic bulge enable strict tests of competing models of the Milky Way. Previo…

2019 The Astrophysical Journal Supplement Series
Gaia eHST 89
The X-ray properties of z > 6 quasars: no evident evolution of accretion physics in the first Gyr of the Universe
DOI: 10.1051/0004-6361/201936217 Bibcode: 2019A&A...630A.118V

Bauer, F. E.; Brandt, W. N.; Vignali, C. +10 more

Context. X-ray emission from quasars (QSOs) has been used to assess supermassive black hole accretion properties up to z ≈ 6. However, at z > 6 only ≈15 QSOs are covered by sensitive X-ray observations, preventing a statistically significant investigation of the X-ray properties of the QSO population in the first Gyr of the Universe.
Aims:…

2019 Astronomy and Astrophysics
XMM-Newton 89
Expanding associations in the Vela-Puppis region. 3D structure and kinematics of the young population
DOI: 10.1051/0004-6361/201834957 Bibcode: 2019A&A...626A..17C

Jordi, C.; Cantat-Gaudin, T.; Balaguer-Núñez, L. +9 more

Context. The Vela-Puppis region is known to host the Vela OB2 association as well as several young clusters featuring OB and pre-main-sequence stars. Several spatial and kinematic subgroups have been identified in recent years.
Aims: By grouping stars based on their positions and velocity, we can address the question of the dynamical history …

2019 Astronomy and Astrophysics
Gaia 89
Extended stellar systems in the solar neighborhood . II. Discovery of a nearby 120° stellar stream in Gaia DR2
DOI: 10.1051/0004-6361/201834950 Bibcode: 2019A&A...622L..13M

Meingast, Stefan; Alves, João; Fürnkranz, Verena

We report the discovery of a large, dynamically cold, coeval stellar stream that is currently traversing the immediate solar neighborhood at a distance of only 100 pc. The structure was identified in a wavelet decomposition of the 3D velocity space of all stars within 300 pc of the Sun. Its members form a highly elongated structure with a length o…

2019 Astronomy and Astrophysics
Gaia 88
Implications of the Warm Corona and Relativistic Reflection Models for the Soft Excess in Mrk 509
DOI: 10.3847/1538-4357/aaf739 Bibcode: 2019ApJ...871...88G

Steiner, James F.; Wilms, Jörn; Ricci, Claudio +15 more

We present the analysis of the first Nuclear Spectroscopic Telescope Array observations (∼220 ks), simultaneous with the last Suzaku observations (∼50 ks), of the active galactic nucleus of the bright Seyfert 1 galaxy Mrk 509. The time-averaged spectrum in the 1-79 keV X-ray band is dominated by a power-law continuum (Γ ∼ 1.8-1.9), a strong soft e…

2019 The Astrophysical Journal
Suzaku 88
Long-term monitoring of the outgassing and composition of comet 67P/Churyumov-Gerasimenko with the Rosetta/MIRO instrument
DOI: 10.1051/0004-6361/201834960 Bibcode: 2019A&A...630A..19B

Hartogh, P.; Lellouch, E.; Crovisier, J. +14 more

We present the analysis of ≈100 molecular maps of the coma of comet 67P/Churyumov-Gerasimenko that were obtained with the MIRO submillimeter radiotelescope on board the Rosetta spacecraft. From the spectral line mapping of H216O, H218O, H217O, CH3OH, NH3, and C…

2019 Astronomy and Astrophysics
Rosetta 88
Supermassive Black Hole Binary Candidates from the Pan-STARRS1 Medium Deep Survey
DOI: 10.3847/1538-4357/ab40cb Bibcode: 2019ApJ...884...36L

Tonry, J.; Huber, M. E.; Waters, C. +9 more

We present a systematic search for periodically varying quasar and supermassive black hole binary (SMBHB) candidates in the Pan-STARRS1 Medium Deep Survey (MDS). From ∼9000 color-selected quasars in an ∼50 °2 sky area, we initially identify 26 candidates with more than 1.5 cycles of variation. We extend the baseline of observations via …

2019 The Astrophysical Journal
XMM-Newton eHST 88
Galactic Winds in Low-mass Galaxies
DOI: 10.3847/1538-4357/ab4c37 Bibcode: 2019ApJ...886...74M

Skillman, Evan D.; van Zee, Liese; McQuinn, Kristen. B. W.

Stellar-feedback-driven outflows are predicted to play a fundamental role in the baryon cycle of low-mass galaxies. However, observational constraints of winds in nearby dwarf galaxies are limited, as outflows are transient, intrinsically low surface brightness features and thus difficult to detect. Using deep Hα observations, we search for winds …

2019 The Astrophysical Journal
eHST 87
Ross Ice Shelf response to climate driven by the tectonic imprint on seafloor bathymetry
DOI: 10.1038/s41561-019-0370-2 Bibcode: 2019NatGe..12..441T

Tinto, K. J.; Padman, L.; Siddoway, C. S. +28 more

Ocean melting has thinned Antarctica's ice shelves at an increasing rate over the past two decades, leading to loss of grounded ice. The Ross Ice Shelf is currently close to steady state but geological records indicate that it can disintegrate rapidly, which would accelerate grounded ice loss from catchments equivalent to 11.6 m of global sea leve…

2019 Nature Geoscience
Rosetta 87
On the slow solar wind with high Alfvénicity: from composition and microphysics to spectral properties
DOI: 10.1093/mnras/sty3329 Bibcode: 2019MNRAS.483.4665D

D'Amicis, Raffaella; Bruno, Roberto; Matteini, Lorenzo

Alfvénic fluctuations are very common features in the solar wind and are found especially within the main portion of fast-wind streams while the slow wind usually is less Alfvénic and more variable. In general, the fast and slow winds show many differences, which span from the large-scale structure to small-scale phenomena, including also a differ…

2019 Monthly Notices of the Royal Astronomical Society
SolarOrbiter 87