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Gamma-Ray Burst Jet Breaks Revisited
DOI: 10.3847/1538-4357/aabc13 Bibcode: 2018ApJ...859..160W

Zhang, Bing; Lin, Da-Bin; Li, Jing +4 more

Gamma-ray Burst (GRB) collimation has been inferred with the observations of achromatic steepening in GRB light curves, known as jet breaks. Identifying a jet break from a GRB afterglow light curve allows a measurement of the jet opening angle and true energetics of GRBs. In this paper, we re-investigate this problem using a large sample of GRBs t…

2018 The Astrophysical Journal
INTEGRAL 85
Black Hole Mass Scaling Relations for Spiral Galaxies. II. M BH-M *,tot and M BH-M *,disk
DOI: 10.3847/1538-4357/aae820 Bibcode: 2018ApJ...869..113D

Graham, Alister W.; Davis, Benjamin L.; Cameron, Ewan

Black hole mass (M BH) scaling relations are typically derived using the properties of a galaxy’s bulge and samples dominated by (high-mass) early-type galaxies. Studying late-type galaxies should provide greater insight into the mutual growth of black holes and galaxies in more gas-rich environments. We have used 40 spiral galaxies to …

2018 The Astrophysical Journal
eHST 85
Detection of Helium in the Atmosphere of the Exo-Neptune HAT-P-11b
DOI: 10.3847/2041-8213/aaf166 Bibcode: 2018ApJ...868L..34M

Fortney, Jonathan J.; Stevenson, Kevin B.; Désert, Jean-Michel +11 more

The helium absorption triplet at a wavelength of 10833 Å has been proposed as a way to probe the escaping atmospheres of exoplanets. Recently this feature was detected for the first time using Hubble Space Telescope (HST) WFC3 observations of the hot Jupiter WASP-107b. We use similar HST/WFC3 observations to detect helium in the atmosphere of the …

2018 The Astrophysical Journal
eHST 85
The Resolved Stellar Populations in the LEGUS Galaxies1
DOI: 10.3847/1538-4365/aaa8e5 Bibcode: 2018ApJS..235...23S

Schaerer, D.; Östlin, G.; Herrero, A. +52 more

The Legacy ExtraGalactic UV Survey (LEGUS) is a multiwavelength Cycle 21 Treasury program on the Hubble Space Telescope. It studied 50 nearby star-forming galaxies in 5 bands from the near-UV to the I-band, combining new Wide Field Camera 3 observations with archival Advanced Camera for Surveys data. LEGUS was designed to investigate how star form…

2018 The Astrophysical Journal Supplement Series
eHST 85
The VIMOS Ultra-Deep Survey: Emerging from the dark, a massive proto-cluster at z 4.57
DOI: 10.1051/0004-6361/201730870 Bibcode: 2018A&A...615A..77L

Maccagni, D.; Berta, S.; Ilbert, O. +20 more

Using spectroscopic observations taken for the Visible Multi-Object Spectrograph (VIMOS) Ultra-Deep Survey (VUDS) we report here on the discovery of PCl J1001+0220, a massive proto-cluster of galaxies located at zspec ~ 4.57 in the COSMOS field. With nine spectroscopic members, the proto-cluster was initially detected as a ~12σ spectros…

2018 Astronomy and Astrophysics
eHST 85
Saturn's magnetic field revealed by the Cassini Grand Finale
DOI: 10.1126/science.aat5434 Bibcode: 2018Sci...362.5434D

Cao, Hao; Dougherty, Michele K.; Hunt, Gregory J. +10 more

During 2017, the Cassini fluxgate magnetometer made in situ measurements of Saturn's magnetic field at distances ~2550 ± 1290 kilometers above the 1-bar surface during 22 highly inclined Grand Finale orbits. These observations refine the extreme axisymmetry of Saturn's internal magnetic field and show displacement of the magnetic equator northward…

2018 Science
Cassini 84
Detection of hydrogen sulfide above the clouds in Uranus's atmosphere
DOI: 10.1038/s41550-018-0432-1 Bibcode: 2018NatAs...2..420I

Fletcher, Leigh N.; Bézard, Bruno; Irwin, Patrick G. J. +4 more

Visible-to-near-infrared observations indicate that the cloud top of the main cloud deck on Uranus lies at a pressure level of between 1.2 bar and 3 bar. However, its composition has never been unambiguously identified, although it is widely assumed to be composed primarily of either ammonia or hydrogen sulfide (H2S) ice. Here, we prese…

2018 Nature Astronomy
eHST 84
Deep Learning Identifies High-z Galaxies in a Central Blue Nugget Phase in a Characteristic Mass Range
DOI: 10.3847/1538-4357/aabfed Bibcode: 2018ApJ...858..114H

Huertas-Company, M.; Dekel, A.; Koo, D. C. +11 more

We use machine learning to identify in color images of high-redshift galaxies an astrophysical phenomenon predicted by cosmological simulations. This phenomenon, called the blue nugget (BN) phase, is the compact star-forming phase in the central regions of many growing galaxies that follows an earlier phase of gas compaction and is followed by a c…

2018 The Astrophysical Journal
eHST 84
The MUSE Hubble Ultra Deep Field Survey. XI. Constraining the low-mass end of the stellar mass - star formation rate relation at z < 1
DOI: 10.1051/0004-6361/201833136 Bibcode: 2018A&A...619A..27B

Bacon, Roland; Bouché, Nicolas; Inami, Hanae +16 more

Star-forming galaxies have been found to follow a relatively tight relation between stellar mass (M*) and star formation rate (SFR), dubbed the "star formation sequence". A turnover in the sequence has been observed, where galaxies with M* < 1010 M follow a steeper relation than their higher mass cou…

2018 Astronomy and Astrophysics
eHST 84
The Steady Global Corona and Solar Wind: A Three-dimensional MHD Simulation with Turbulence Transport and Heating
DOI: 10.3847/1538-4357/aad687 Bibcode: 2018ApJ...865...25U

Matthaeus, William H.; Goldstein, Melvyn L.; Usmanov, Arcadi V. +1 more

We present a fully three-dimensional magnetohydrodynamic model of the solar corona and solar wind with turbulence transport and heating. The model is based on Reynolds-averaged solar wind equations coupled with transport equations for turbulence energy, cross helicity, and correlation scale. The model includes separate energy equations for protons…

2018 The Astrophysical Journal
Ulysses 84