Search Publications
Haze Seasonal Variations of Titan's Upper Atmosphere during the Cassini Mission
West, Robert A.; Vinatier, Sandrine; Seignovert, Benoît +1 more
This study presents a 13 yr survey of haze UV extinction profiles, monitoring the temporal evolution of the detached haze layer (DHL) in Titan's upper atmosphere (350-600 km). As reported by West et al. (GRL vol.38, L06204) at the equator, we show that the DHL was present at all latitudes below 55°N during the northern winter (2004-2009). Subseque…
Detection of Lyman Continuum from 3.0 < z < 3.5 Galaxies in the HETDEX Survey
Finkelstein, Steven L.; Schneider, Donald P.; Chisholm, John +15 more
Questions as to what drove the bulk reionization of the universe, how that reionization proceeded, and how the hard ionizing radiation reached the intergalactic medium remain open and debated. Observations probing that epoch are severely hampered by the increasing amounts of neutral gas with increasing redshift, so a small, but growing, number of …
Imaging Evidence for Solar Wind Outflows Originating from a Coronal Mass Ejection Footpoint
Golub, Leon; Aulanier, Guillaume; Schmieder, Brigitte +2 more
We report on Atmospheric Imaging Assembly observations of plasma outflows originating in a coronal dimming during a 2015 April 28 filament eruption. After the filament started to erupt, two flare ribbons formed, one of which had a well-visible hook enclosing a core (twin) dimming region. Along multiple funnels located in this dimming, a motion of …
The TESS View of LOFAR Radio-emitting Stars
Pope, Benjamin J. S.; Günther, Maximilian N.; Ansdell, Megan +4 more
The recent detection of the M dwarf GJ 1151 at 144 MHz low radio frequencies using LOFAR has been interpreted as evidence of an exoplanet magnetically interacting with its host star. This would be the first exoplanet detected around a main-sequence star by a radio telescope. Radial velocity confirmation of such a planet has proven inconclusive and…
A ΔR ∼ 9.5 mag Superflare of an Ultracool Star Detected by the SVOM/GWAC System
Xu, Y.; Huang, L.; Wang, J. +21 more
We report the detection and follow-up of a superstellar flare GWAC 181229A with an amplitude of ΔR ∼ 9.5 mag on an M9-type star by SVOM/GWAC and the dedicated follow-up telescopes. The estimated bolometric energy Ebol is (5.56-9.25) × 1034 erg, which makes the event one of the most powerful flares seen on ultracool stars. The…
Exploring the Galactic Anticenter Substructure with LAMOST and Gaia DR2
Tian, Hao; Zhao, Gang; Wu, Yaqian +12 more
We characterize the kinematic and chemical properties of 589 Galactic anticenter substructure stars (GASS) with K/M giants in integrals-of-motion space. These stars likely include members of previously identified substructures such as Monoceros, A13, and the Triangulum-Andromeda cloud. We show that these stars are in nearly circular orbits on both…
The Formation Process of the First Halo Coronal Mass Ejection in Solar Cycle 25: Magnetic Cancellation, Bidirectional Jet, and Hot Channel
Xue, Zhike; Yan, Xiaoli; Wang, Jincheng +3 more
To better understand the trigger mechanism of a coronal mass ejection (CME), we present the evolution of a CME source region (active region NOAA 12790) and the formation of a hot channel before the occurrence of the first halo CME in solar cycle 25. Through analyzing the evolution of Solar Dynamics Observatory/Helioseismic and Magnetic Imager line…
Longitudinally Resolved Spectral Retrieval (ReSpect) of WASP-43b
Gonzales, Eileen C.; Cubillos, Patricio E.; Cowan, Nicolas B. +6 more
Thermal phase variations of short-period planets indicate that they are not spherical cows: day-to-night temperature contrasts range from hundreds to thousands of degrees, rivaling their vertical temperature contrasts. Nonetheless, the emergent spectra of short-period planets have typically been fit using one-dimensional (1D) spectral retrieval co…
Synthetic Absorption Lines from Simulations of Multiphase Gas in Galactic Winds
Ostriker, Eve C.; de la Cruz, Lita M.; Schneider, Evan E.
Supernova-driven galactic winds are multiphase streams of gas that are often observed flowing at a range of velocities out of star-forming regions in galaxies. In this study, we use high-resolution 3D simulations of multiphase galactic winds modeled with the hydrodynamics code Cholla to investigate the connection between numerical studies and obse…
Late-time Hubble Space Telescope Observations of a Hydrogen-poor Superluminous Supernova Reveal the Power-law Decline of a Magnetar Central Engine
Berger, Edo; Chornock, Ryan; Nicholl, Matt +3 more
The light-curve diversity of hydrogen-poor superluminous supernovae (SLSNe) has kept open the possibility that multiple power sources account for the population. Specifically, pair-instability explosions (PISNe), which produce large masses of 56Ni, have been argued as the origin of some slowly-evolving SLSNe. Here we present detailed ob…