Search Publications

The TeV-emitting radio galaxy 3C 264. VLBI kinematics and SED modeling
DOI: 10.1051/0004-6361/201935183 Bibcode: 2019A&A...627A..89B

Vignali, C.; Grandi, P.; Boccardi, B. +5 more

Context. In March 2018, the detection by VERITAS of very-high-energy emission (VHE > 100 GeV) from 3C 264 was reported. This is the sixth, and second most distant, radio galaxy ever detected in the TeV regime.
Aims: In this article we present a radio and X-ray analysis of the jet in 3C 264. We determine the main physical parameters of the …

2019 Astronomy and Astrophysics
XMM-Newton 18
Accurate mass and radius determinations of a cool subdwarf in an eclipsing binary
DOI: 10.1038/s41550-019-0746-7 Bibcode: 2019NatAs...3..553R

Rebassa-Mansergas, Alberto; Parsons, Steven G.; Torres, Santiago +4 more

Cool subdwarfs are metal-poor low-mass stars that formed during the early stages of the evolution of our Galaxy. Because they are relatively rare in the vicinity of the Sun, we know of few cool subdwarfs in the solar neighbourhood, and none for which both the mass and the radius are accurately determined. This hampers our understanding of stars at…

2019 Nature Astronomy
Gaia 18
The Role of Clathrate Formation in Europa’s Ocean Composition
DOI: 10.3847/1538-4357/ab40b0 Bibcode: 2019ApJ...885...14B

Mousis, Olivier; Bouquet, Alexis; Danger, Grégoire +2 more

We use a thermodynamic statistical model to evaluate how the composition of Europa’s internal ocean may have been affected by clathrate hydrate formation. Assuming an input of the observed O2 and CO2 from the surface into a mildly acidic ocean (pH < 6), and considering the possibility of contributions by reduced (with CH

2019 The Astrophysical Journal
Rosetta 18
The Storm-Time Ring Current Response to ICMEs and CIRs Using Van Allen Probe Observations
DOI: 10.1029/2019JA026695 Bibcode: 2019JGRA..124.9017M

Mitchell, D. G.; Farrugia, C. J.; Kistler, L. M. +6 more

Using Van Allen Probe observations of the inner magnetosphere during geomagnetic storms driven by interplanetary coronal mass ejections (ICMEs) and corotating interaction regions (CIRs), we characterize the impact of these drivers on the storm-time ring current development. Using 25 ICME- and 35 CIR-driven storms, we have determined the ring curre…

2019 Journal of Geophysical Research (Space Physics)
Cluster 18
The second-degree gravity coefficients of Phobos from two Mars Express flybys
DOI: 10.1093/mnras/stz2695 Bibcode: 2019MNRAS.490.2007Y

Pätzold, M.; Hahn, M.; Andert, T. +6 more

Several close spacecraft flybys of Phobos have been performed over the past 40 yr in order to determine the gravity field of this tiny Martian moon. In this work, the second-degree coefficients of the gravity field of Phobos were derived from the radio tracking data of two combined Mars Express flybys (2010 and 2013), by applying a least squares r…

2019 Monthly Notices of the Royal Astronomical Society
MEx 18
Small Planets in the Galactic Context: Host Star Kinematics, Iron, and Alpha-element Enhancement
DOI: 10.3847/1538-3881/ab27c9 Bibcode: 2019AJ....158...61B

Bashi, Dolev; Zucker, Shay

We explored the occurrence rate of small close-in planets among Kepler target stars as a function of the iron abundance and the stellar total velocity {V}tot}. We estimated the occurrence rate of those planets by combining information from the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) and the California-Kepler S…

2019 The Astronomical Journal
Gaia 18
Origin of a Massive Hyper-runaway Subgiant Star LAMOST-HVS1: Implication from Gaia and Follow-up Spectroscopy
DOI: 10.3847/1538-4357/ab05c8 Bibcode: 2019ApJ...873..116H

Mahler, Guillaume; Hattori, Kohei; Castro, Norberto +3 more

We report that LAMOST-HVS1 is a massive hyper-runaway subgiant star with a mass of 8.3 {M} and super-solar metallicity, which was ejected from the inner stellar disk of the Milky Way ∼33 {Myr} ago with the intrinsic ejection velocity of {568}-17+19 {km} {{{s}}}-1 (corrected for the streaming motion of …

2019 The Astrophysical Journal
Gaia 18
Evolution of the Coronal Cavity From the Quiescent to Eruptive Phase Associated with Coronal Mass Ejection
DOI: 10.3847/1538-4357/ab11c5 Bibcode: 2019ApJ...875..101S

West, Matthew J.; Srivastava, Nandita; Mierla, Marilena +2 more

We present the evolution of a coronal cavity encompassing its quiescent and eruptive phases in the lower corona. Using multiple vantage-point observations from the SDO/AIA, STEREO SECCHI/EUVI, and PROBA2/Sun Watcher with the APS and Image Processing (SWAP) extreme ultraviolet (EUV) imagers, we capture a sequence of quasi-static equilibria of the q…

2019 The Astrophysical Journal
PROBA-2 SOHO 18
Automated Swirl Detection Algorithm (ASDA) and Its Application to Simulation and Observational Data
DOI: 10.3847/1538-4357/aabd34 Bibcode: 2019ApJ...872...22L

Liu, Jiajia; Erdélyi, Robertus; Nelson, Chris J.

Swirling motions in the solar atmosphere have been widely observed in recent years and suggested to play a key role in channeling energy from the photosphere into the corona. Here, we present a newly developed Automated Swirl Detection Algorithm (ASDA) and discuss its applications. ASDA is found to be very proficient at detecting swirls in a varie…

2019 The Astrophysical Journal
Hinode 18
On the emergence of THOUSANDS of absorption lines in the quasar PG 1411+442: a clumpy high-column density outflow from the broad emission-line region?
DOI: 10.1093/mnras/stz1408 Bibcode: 2019MNRAS.487.5041H

Tripp, Todd M.; Hamann, Fred; Veilleux, Sylvain +1 more

Quasar outflows are fundamental components of quasar environments that might play an important role in feedback to galaxy evolution. We report on the emergence of a remarkable new outflow absorption-line system in the quasar PG1411+442 (redshift ∼0.089) detected in the UV and visible with the Hubble Space Telescope Cosmic Origins Spectrograph and …

2019 Monthly Notices of the Royal Astronomical Society
eHST 18