Search Publications
ALMA CO Observations of Supernova Remnant N63A in the Large Magellanic Cloud: Discovery of Dense Molecular Clouds Embedded within Shock-ionized and Photoionized Nebulae
Filipović, M. D.; Rowell, G.; Sasaki, M. +19 more
We carried out new 12CO(J = 1-0, 3-2) observations of a N63A supernova remnant (SNR) from the LMC using the Atacama Large Millimeter/submillimeter Array (ALMA) and Atacama Submillimeter Telescope Experiment. We find three giant molecular clouds toward the northeast, east, and near the center of the SNR. Using the ALMA data, we spatially…
Spectroscopic and astrometric radial velocities: Hyades as a benchmark
Pasquini, L.; Ludwig, H. -G.; de Medeiros, J. R. +1 more
We study the accuracy of spectroscopic radial velocities (RVs) by comparing spectroscopic and astrometric RVs for stars of the Hyades open cluster. We obtained High-Accuracy Radial velocity Planet Searcher (HARPS) spectra for a large sample of Hyades stars and combined them with accurate astrometric RVs based on Hipparcos and Gaia data. After clea…
Hinode EIS line widths in the quiet corona up to 1.5 R⊙
Mason, H. E.; Del Zanna, G.; Gupta, G. R.
We present an analysis of several Hinode Extreme-ultraviolet Imaging Spectrometer (EIS) observations of coronal line widths in the quiet Sun, up to 1.5 R⊙ radial distances. Significant variations are found, which indicates no damping of Alfvén waves in the quiescent corona. However, the uncertainties in estimating the instrumental width…
Seasonal formation rates of martian slope streaks
Jaumann, R.; Hiesinger, H.; Kreslavsky, M. +3 more
Slope streaks are gravity-driven dark or light-toned features that form throughout the martian year in high-albedo and low-thermal inertia equatorial regions on Mars. These distinctive features have never been observed in a terrestrial environment although some analogs have been proposed. Based on diverse orbital observations, a number of mechanis…
General study of chameleon fifth force in gravity space experiments
Bergé, Joel; Pernot-Borràs, Martin; Uzan, Jean-Philippe +1 more
In this article we investigate the profile of the scalar field of a scalar-tensor theory subject to the chameleon mechanism in the context of gravity space missions like the MICROSCOPE experiment. We analyze the experimental situations for models with an inverse power-law potential that can in principle induce a fifth force inside the satellite, a…
Physical properties of γ Doradus pulsating stars and their relationship with long-period δ Scuti variables
Li, Lin-Jia; Qian, Sheng-Bang; Zhu, Li-Ying +3 more
We present LAMOST data on 168 γ Doradus (γ Dor) pulsating stars including stellar atmospheric parameters of 137 variables and spectral types for all of the samples. The distributions of period (P), temperature (T), gravitational acceleration (log(g)) and metallicity [Fe/H] are shown. It is found that most γ Dor variables are main-sequence stars wi…
Consistent radial velocities of classical Cepheids from the cross-correlation technique
Kervella, P.; Anderson, R. I.; Trahin, B. +11 more
Context. Accurate radial velocities (vrad) of Cepheids are mandatory within the context of Cepheid distance measurements using the Baade-Wesselink technique. The most common vrad derivation method consists in cross-correlating the observed stellar spectra with a binary template and measuring a velocity on the resulting mean p…
Resolving accretion flows in nearby active galactic nuclei with the Event Horizon Telescope
Nagar, Neil M.; Ramakrishnan, Venkatessh; Xie, Fu-Guo +5 more
The Event Horizon Telescope (EHT), now with its first ever image of the photon ring around the supermassive black hole of M87, provides a unique opportunity to probe the physics of supermassive black holes through Very Long Baseline Interferometry (VLBI), such as the existence of the event horizon, the accretion processes as well as jet formation …
Groundwater Control and Process Variability on the Equatorial Layered Deposits of Kotido Crater, Mars
Hauber, E.; Rossi, A. P.; Pondrelli, M. +4 more
Understanding the origin of the Hesperian-aged sulfate-bearing Equatorial Layered Deposits (ELDs) is crucial to infer Mars' climatic conditions during their formation and to assess their habitability potential. We investigated well-exposed ELDs in Kotido crater (Arabia Terra) and produced a detailed geological map of the crater infill, distinguish…
A Search for Spatially Resolved Infrared Rovibrational Molecular Hydrogen Emission from the Disks of Young Stars
Beck, Tracy L.; Bary, Jeffrey S.
We present results from a survey searching for spatially resolved near-infrared line emission from molecular hydrogen gas in the circumstellar environments of nine young stars: AA Tau, AB Aur, DoAr 21, GG Tau, GM Aur, LkCa 15, LkHα 264, UY Aur, and V773 Tau. Prior high-resolution spectra of these stars showed the presence of rovibrational H2<…