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FIGS—Faint Infrared Grism Survey: Description and Data Reduction
Finkelstein, Steven L.; Hathi, Nimish P.; Koekemoer, Anton M. +26 more
The Faint Infrared Grism Survey (FIGS) is a deep Hubble Space Telescope (HST) WFC3/IR (Wide Field Camera 3 Infrared) slitless spectroscopic survey of four deep fields. Two fields are located in the Great Observatories Origins Deep Survey-North (GOODS-N) area and two fields are located in the Great Observatories Origins Deep Survey-South (GOODS-S) …
ALMA Observations of Starless Core Substructure in Ophiuchus
Di Francesco, J.; Sadavoy, S. I.; Johnstone, D. +11 more
Compact substructure is expected to arise in a starless core as mass becomes concentrated in the central region likely to form a protostar. Additionally, multiple peaks may form if fragmentation occurs. We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 2 observations of 60 starless and protostellar cores in the Ophiuchus molecul…
Space Motions of the Dwarf Spheroidal Galaxies Draco and Sculptor Based on HST Proper Motions with a ∼10 yr Time Baseline
van der Marel, Roeland P.; van de Ven, Glenn; Bellini, Andrea +6 more
We present new proper motion (PM) measurements of the dwarf spheroidal galaxies (dSphs) Draco and Sculptor using multiepoch images obtained with the Hubble Space Telescope ACS/WFC. Our PM results have uncertainties far lower than previous measurements, even those made with the same instrument. The PM results for Draco and Sculptor are ({µ }<…
Very Deep inside the SN 1987A Core Ejecta: Molecular Structures Seen in 3D
van Loon, J. Th.; Larsson, J.; Lundqvist, P. +21 more
Most massive stars end their lives in core-collapse supernova explosions and enrich the interstellar medium with explosively nucleosynthesized elements. Following core collapse, the explosion is subject to instabilities as the shock propagates outward through the progenitor star. Observations of the composition and structure of the innermost regio…
Constraints on Quenching of Z ≲ 2 Massive Galaxies from the Evolution of the Average Sizes of Star-forming and Quenched Populations in COSMOS
Ilbert, O.; Scoville, N. Z.; Carollo, C. M. +5 more
We use >9400 {log}(m/{M}⊙ )> 10 quiescent and star-forming galaxies at z ≲ 2 in COSMOS/UltraVISTA to study the average size evolution of these systems, with focus on the rare ultra-massive population at {log}(m/{M}⊙ )> 11.4. The large 2 square degree survey area delivers a sample of ∼400 such ultra-massive systems. A…
ALMA Measurements of Circumstellar Material in the GQ Lup System
Herczeg, Gregory J.; MacGregor, Meredith A.; Wilner, David J. +7 more
We present Atacama Large Millimeter/submillimeter Array observations of the GQ Lup system, a young Sun-like star with a substellar-mass companion in a wide-separation orbit. These observations of 870 µm continuum and CO J = 3-2 line emission with beam size ∼0.″3 (∼45 au) resolve the disk of dust and gas surrounding the primary star, GQ Lup A…
The Solar Energetic Particle Event of 2010 August 14: Connectivity with the Solar Source Inferred from Multiple Spacecraft Observations and Modeling
Thompson, B. J.; Lario, D.; Kwon, R. -Y. +13 more
We analyze one of the first solar energetic particle (SEP) events of solar cycle 24 observed at widely separated spacecraft in order to assess the reliability of models currently used to determine the connectivity between the sources of SEPs at the Sun and spacecraft in the inner heliosphere. This SEP event was observed on 2010 August 14 by near-E…
A Comet Active Beyond the Crystallization Zone
Mutchler, Max; Jewitt, David; Agarwal, Jessica +3 more
We present observations showing inbound long-period comet C/2017 K2 (PANSTARRS) to be active at a record heliocentric distance. Nucleus temperatures are too low (60-70 K) either for water ice to sublimate or for amorphous ice to crystallize, requiring another source for the observed activity. Using the Hubble Space Telescope we find a sharply boun…
A Parameter Study for Modeling Mg II h and k Emission during Solar Flares
Kleint, Lucia; Rubio da Costa, Fatima
Solar flares show highly unusual spectra in which the thermodynamic conditions of the solar atmosphere are encoded. Current models are unable to fully reproduce the spectroscopic flare observations, especially the single-peaked spectral profiles of the Mg II h and k lines. We aim to understand the formation of the chromospheric and optically thick…
HST Imaging of the Brightest z ∼ 8-9 Galaxies from UltraVISTA: The Extreme Bright End of the UV Luminosity Function
Holwerda, Benne W.; Franx, Marijn; Illingworth, Garth D. +13 more
We report on the discovery of three especially bright candidate {z}{phot}≳ 8 galaxies. Five sources were targeted for follow-up with the Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3), selected from a larger sample of 16 bright (24.8≲ H≲ 25.5 mag) candidate z≳ 8 Lyman break galaxies (LBGs) identified over 1.6 degrees2