Search Publications

67P/Churyumov-Gerasimenko active areas before perihelion identified by GIADA and VIRTIS data fusion
DOI: 10.1093/mnras/sty3244 Bibcode: 2019MNRAS.483.2165L

Fulle, M.; Erard, S.; Capaccioni, F. +16 more

We characterized 67P/Churyumov-Gerasimenko's cometary activity during its inbound arc before perihelion (2014 August-2015 January). We focused on the geomorphological regions of the Northern hemisphere observed by the ESA/Rosetta space probe during this time period. The GIADA dust detector characterized the physical properties of the fluffy and co…

2019 Monthly Notices of the Royal Astronomical Society
Rosetta 9
A Radial Velocity Survey of Embedded Sources in the Rho Ophiuchi Cluster
DOI: 10.3847/1538-3881/ab24c0 Bibcode: 2019AJ....158...41S

Greene, Thomas P.; Gibb, Erika L.; Wilking, Bruce A. +3 more

We present the results of a radial velocity survey of young stellar objects (YSOs) in early stages of evolution in the core of the L1688 molecular cloud. New and archival spectra obtained with four high-resolution infrared spectrographs were analyzed using Markov chain Monte Carlo techniques that simultaneously fit for the radial velocity, T

2019 The Astronomical Journal
Gaia 9
Constraining the magnetic field on white dwarf surfaces; Zeeman effects and fine structure constant variation
DOI: 10.1093/mnras/stz739 Bibcode: 2019MNRAS.485.5050H

Barstow, M. A.; Holberg, J. B.; Webb, J. K. +12 more

White dwarf (WD) atmospheres are subjected to gravitational potentials around 105 times larger than occur on Earth. They provide a unique environment in which to search for any possible variation in fundamental physics in the presence of strong gravitational fields. However, a sufficiently strong magnetic field will alter absorption lin…

2019 Monthly Notices of the Royal Astronomical Society
eHST 9
Dust and Snow Cover on Saturn's Icy Moons
DOI: 10.1029/2019GL084218 Bibcode: 2019GeoRL..4611747L

West, R. D.; Le Gall, A.; Bonnefoy, L. E.

The final analysis of the Cassini radar observations of Saturn's icy moons presented here shows that the exchange of material between the planet's dust rings and moons, which is specific to the Saturnian system, plays a key role in the current state of the airless satellite regolith. Far from Saturn, the vast debris ring from Phoebe progressively …

2019 Geophysical Research Letters
Cassini 9
Subaru narrow-band imaging search for Lyman continuum from galaxies at z > 3 in the GOODS-N field
DOI: 10.1093/mnras/stz2081 Bibcode: 2019MNRAS.488.5671I

Inoue, Akio K.; Yamada, Toru; Iwata, Ikuru +2 more

We report results of a search for galaxies at z > 3 with Lyman continuum (LyC) emission using a narrow-band filter NB359 with Subaru/Suprime-Cam in an ∼800 arcmin2 blank field around the GOODS-N. We use 103 star-forming galaxies (SFGs) and 8 active galactic nuclei (AGNs) with spectroscopic redshifts in a range between 3.06 and 3.5 an…

2019 Monthly Notices of the Royal Astronomical Society
eHST 9
Leaves on trees: identifying halo stars with extreme gradient boosted trees
DOI: 10.1051/0004-6361/201732303 Bibcode: 2019A&A...621A..13V

Helmi, Amina; Veljanoski, Jovan; Breddels, Maarten +1 more

Context. Extended stellar haloes are a natural by-product of the hierarchical formation of massive galaxies like the Milky Way. If merging is a non-negligible factor in the growth of our Galaxy, evidence of such events should be encoded in its stellar halo. The reliable identification of genuine halo stars is a challenging task, however.
Aims…

2019 Astronomy and Astrophysics
Gaia 9
Empirical Modeling of the Geomagnetosphere for SIR and CME-Driven Magnetic Storms
DOI: 10.1029/2018JA026008 Bibcode: 2019JGRA..124.5641A

Tsyganenko, N. A.; Andreeva, V. A.

During geomagnetic disturbances, the solar wind arrives in the form of characteristic sequences lasting from tens of hours to days. The most important magnetic storm drivers are the coronal mass ejections (CMEs) and the slow-fast stream interaction regions (SIRs). Previous data-based magnetic field models did not distinguish between these types of…

2019 Journal of Geophysical Research (Space Physics)
Cluster 9
Finding the Critical Decay Index in Solar Prominence Eruptions
DOI: 10.3847/1538-4357/ab4793 Bibcode: 2019ApJ...885...89V

Ravindra, B.; Doddamani, V. H.; Vemareddy, P. +1 more

The background field is assumed to play a prime role in erupting structures like prominences. In the flux rope models, the critical decay index (n c ) is a measure of the rate at which background field intensity decreases with height over the flux rope or erupting structure. In the real observations, the critical height of the backgrou…

2019 The Astrophysical Journal
SOHO 9
Young open cluster IC 4996 and its vicinity: multicolor photometry and Gaia DR2 astrometry
DOI: 10.1051/0004-6361/201833987 Bibcode: 2019A&A...623A..22S

Munari, U.; Straižys, V.; Raudeliūnas, S. +9 more

The open cluster IC 4996 in Cygnus and its vicinity are investigated by applying a two-dimensional photometric classification of stars measured in the Vilnius seven-color photometric system. Cluster members are identified by applying distances based on the Gaia DR2 parallaxes and the point vector diagram of the Gaia DR2 proper motions. For some B-…

2019 Astronomy and Astrophysics
Gaia 9
OGLE-2018-BLG-0022: A Nearby M-dwarf Binary
DOI: 10.3847/1538-3881/ab1538 Bibcode: 2019AJ....157..215S

Saha, A.; Lowry, S.; Mao, S. +32 more

We report observations of the binary microlensing event OGLE-2018-BLG-0022, provided by the Robotic Observations of Microlensing Events (ROME)/Reactive Event Assessment (REA) Survey, which indicate that the lens is a low-mass binary star consisting of M3 (0.375 ± 0.020 M ) and M7 (0.098 ± 0.005 M ) components. The lens is u…

2019 The Astronomical Journal
Gaia 9