Search Publications

ACCESS: Ground-based Optical Transmission Spectroscopy of the Hot Jupiter WASP-4b
DOI: 10.3847/1538-3881/aaf9a3 Bibcode: 2019AJ....157...68B

López-Morales, Mercedes; Jordán, Andrés; Espinoza, Néstor +6 more

We present an optical transmission spectrum of the atmosphere of WASP-4b obtained through observations of four transits with Magellan/IMACS, as part of the Arizona-CfA-Católica-Carnegie Exoplanet Spectroscopy Survey (ACCESS). Using a Bayesian approach to atmospheric retrieval, we find no evidence for scattering or absorption features in our transi…

2019 The Astronomical Journal
Gaia 22
Peculiar Velocities of Galaxies Just Beyond the Local Group
DOI: 10.3847/1538-4357/ab24e5 Bibcode: 2019ApJ...880...52A

Anand, Gagandeep S.; Shaya, Edward J.; Tully, R. Brent +2 more

The Milky Way lies in a thin plane, the Local Sheet, a part of a wall bounding the Local Void lying toward the north supergalactic pole. Galaxies with accurate distances both above and below this supergalactic equatorial plane have systematically negative peculiar velocities. The interpretation of this situation is that the Local Void is expanding…

2019 The Astrophysical Journal
eHST 22
Close Cassini flybys of Saturn's ring moons Pan, Daphnis, Atlas, Pandora, and Epimetheus
DOI: 10.1126/science.aat2349 Bibcode: 2019Sci...364.2349B

Brown, R. H.; Baines, K. H.; Buratti, B. J. +35 more

Saturn's main ring system is associated with a set of small moons that either are embedded within it or interact with the rings to alter their shape and composition. Five close flybys of the moons Pan, Daphnis, Atlas, Pandora, and Epimetheus were performed between December 2016 and April 2017 during the ring-grazing orbits of the Cassini mission. …

2019 Science
Cassini 22
A-type stars in the Canada-France Imaging Survey - II. Tracing the height of the disc at large distances with Blue Stragglers
DOI: 10.1093/mnras/sty3334 Bibcode: 2019MNRAS.483.3119T

Laporte, Chervin F. P.; McConnachie, Alan W.; Malhan, Khyati +7 more

We present the kinematics of Blue Straggler (BS) stars identified in the Canada-France Imaging Survey (CFIS), covering 4000 deg2 on the sky in the u band. The BSs sample, characterized through CFIS and Pan-STARRS photometry, has been kinematically decomposed into putative halo and disc populations after cross-matching with Gaia astromet…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 22
Metallicity dependence of the Hercules stream in Gaia/RAVE data - explanation by non-closed orbits
DOI: 10.1093/mnras/stz266 Bibcode: 2019MNRAS.484.4540H

Hattori, Kohei; Kumamoto, Jun; Tagawa, Hiromichi +4 more

The origin of the Hercules stream, the most prominent velocity substructure in the Solar neighbour disc stars, is still under debate. Recent accurate measurements of position, velocity, and metallicity provided by Tycho Gaia Astrometric Solution (TGAS) and RAdial Velocity Experiments (RAVE) have revealed that the Hercules stream is most clearly se…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 22
Modeling ionized gas in low-metallicity environments: the Local Group dwarf galaxy IC 10
DOI: 10.1051/0004-6361/201833776 Bibcode: 2019A&A...622A.119P

Lebouteiller, V.; Madden, S. C.; Galliano, F. +9 more

Context. Star formation activity is an important driver of galaxy evolution and is influenced by the physical properties of the interstellar medium. Dwarf galaxies allow us to understand how the propagation of radiation and the physical conditions of the different ISM phases are affected by the low-metallicity environment.
Aims: Our objective…

2019 Astronomy and Astrophysics
Herschel 22
Terrestrial ion escape and relevant circulation in space
DOI: 10.5194/angeo-37-1197-2019 Bibcode: 2019AnGeo..37.1197Y

Yamauchi, Masatoshi

Observations of the terrestrial ion escape to space and the transport of escaping ions in the magnetosphere are reviewed, with the main stress on subjects that were not covered in reviews over past 2 decades, during which Cluster has significantly improved our knowledge of them. Here, outflowing ions from the ionosphere are classified in terms of …

2019 Annales Geophysicae
Cluster 22
Collimated radiation in SS 433. Constraints from spatially resolved optical jets and Cloudy modeling of the optical bullets
DOI: 10.1051/0004-6361/201834747 Bibcode: 2019A&A...624A.127W

Dexter, Jason; Waisberg, Idel; Dubus, Guillaume +2 more

Context. The microquasar SS 433 is well known for its precessing, relativistic, and highly collimated baryonic jets, which manifest in its optical spectrum as pairs of hydrogen and helium emission lines moving with large Doppler shifts. Depending on their heating mechanism, the optical jet bullets may serve as a probe of the collimated radiation c…

2019 Astronomy and Astrophysics
Gaia 22
Young stellar populations in early-type dwarf galaxies. Occurrence, radial extent, and scaling relations
DOI: 10.1051/0004-6361/201935076 Bibcode: 2019A&A...625A..94H

Peletier, R. F.; Valentijn, E. A.; Hamraz, E. +3 more


Aims: To understand the stellar population content of early-type dwarf galaxies (dEs) and their environmental dependence, we compare the slopes and intrinsic scatter of color-magnitude relations (CMRs) for three nearby clusters, Fornax, Virgo, and Coma. Additionally, we present and compare internal color profiles of these galaxies to identify…

2019 Astronomy and Astrophysics
eHST 22
Spin Parity of Spiral Galaxies. I. Corroborative Evidence for Trailing Spirals
DOI: 10.3847/1538-4357/ab4a18 Bibcode: 2019ApJ...886..133I

Tadaki, Ken-ichi; Iye, Masanori; Fukumoto, Hideya

Whether the spiral structure of galaxies is trailing or leading has been a subject of debate. We present a new spin parity catalog of 146 spiral galaxies that lists the following three pieces of information: whether the spiral structure observed on the sky is S-wise or Z-wise; which side of the minor axis of the galaxy is darker and redder, based …

2019 The Astrophysical Journal
eHST 22