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Radio, Hard X-Ray, and Gamma-Ray Emissions Associated with a Far-Side Solar Event
Zimovets, I. V.; Grechnev, V. V.; Mitrofanov, I. G. +9 more
The far-side solar eruptive event SOL2014-09-01 produced hard electromagnetic and radio emissions that were observed with detectors at near-Earth vantage points. Especially challenging was a long-duration > 100 MeV γ -ray burst that was probably produced by accelerated protons exceeding 300 MeV. This observation raised the question how high-ene…
Spatial, Seasonal, and Solar Cycle Variations of the Martian Total Electron Content (TEC): Is the TEC a Good Tracer for Atmospheric Cycles?
Indurain, Mikel; González-Galindo, Francisco; Witasse, Olivier +7 more
We analyze 10 years of Mars Express total electron content (TEC) data from the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument. We describe the spatial, seasonal, and solar cycle behavior of the Martian TEC. Due to orbit evolution, data come mainly from the evening, dusk terminator and postdusk nightside. The annual…
Summer outbursts in the coma of comet 67P/Churyumov-Gerasimenko as observed by Rosetta-VIRTIS
D'Aversa, E.; Kappel, D.; Erard, S. +20 more
We present an analysis of transient events observed by the Visible InfraRed Thermal Imaging Spectrometer, instrument aboard Rosetta, for the dates of 2015 August 10, September 13 and 14, during the two months surrounding the comet perihelion passage of the Rosetta spacecraft. We detected and characterized events with life-times ranging from 26 min…
Observations of SN 2015F Suggest a Correlation between the Intrinsic Luminosity of Type Ia Supernovae and the Shape of Their Light Curves >900 Days after Explosion
Zurek, David R.; Rest, Armin; Riess, Adam G. +6 more
The late-time light curves of Type Ia supernovae (SNe Ia), observed >900 days after explosion, present the possibility of a new diagnostic for SN Ia progenitor and explosion models. First, however, we must discover what physical process (or processes) leads to the slow-down of the light curve relative to a pure 56Co decay, as observe…
Asteroseismic radii of dwarfs: new accuracy constraints from Gaia DR2 parallaxes
Silva Aguirre, Victor; Sahlholdt, Christian L.
Precise stellar masses and radii can be determined using asteroseismology, but their accuracy must be tested against independent estimates. Using radii derived from Gaia DR2 parallaxes, we test the accuracy of asteroseismic radii for a sample of 93 dwarfs based on both individual frequency fitting and the seismic scaling relations. Radii from freq…
Plasma Evolution within an Erupting Coronal Cavity
Long, David M.; Harra, Louise K.; Matthews, Sarah A. +5 more
Coronal cavities have previously been observed to be associated with long-lived quiescent filaments and are thought to correspond to the associated magnetic flux rope. Although the standard flare model predicts a coronal cavity corresponding to the erupting flux rope, these have only been observed using broadband imaging data, restricting an analy…
An Iwasawa-Taniguchi effect for Compton-thick active galactic nuclei
Gandhi, Poshak; Ricci, Claudio; Stern, Daniel +4 more
We present the first study of an Iwasawa-Taniguchi/`X-ray Baldwin' effect for Compton-thick active galactic nuclei (AGN). We report a statistically significant anticorrelation between the rest-frame equivalent width (EW) of the narrow core of the neutral Fe Kα fluorescence emission line, ubiquitously observed in the reflection spectra of obscured …
Multiwavelength Observations of a New Redback Millisecond Pulsar Candidate: 3FGL J0954.8-3948
Cheng, K. S.; Strader, Jay; Kong, Albert K. H. +6 more
We present a multiwavelength study of the unassociated Fermi Large Area Telescope (LAT) source, 3FGL J0954.8-3948, which is likely the γ-ray counterpart of a 9.3 hr binary in the field. With more than 9 years of Pass 8 LAT data, we updated the γ-ray spectral properties and the LAT localization of the γ-ray source. While the binary lies outside the…
The Duration of Energy Deposition on Unresolved Flaring Loops in the Solar Corona
Polito, Vanessa; Warren, Harry P.; Crump, Nicholas A. +1 more
Solar flares form and release energy across a large number of magnetic loops. The global parameters of flares, such as the total energy released, duration, physical size, etc., are routinely measured, and the hydrodynamics of a coronal loop subjected to intense heating have been extensively studied. It is not clear, however, how many loops compris…
The BOSS Emission-line Lens Survey. V. Morphology and Substructure of Lensed Lyα Emitters at Redshift Z ≈ 2.5 in the BELLS GALLERY
Brownstein, Joel R.; Marques-Chaves, Rui; Oguri, Masamune +9 more
We present a morphological study of the 17 lensed Lyα emitter (LAE) galaxies of the Baryon Oscillation Spectroscopic Survey Emission-Line Lens Survey (BELLS) for the GALaxy-Lyα EmitteR sYstems (BELLS GALLERY) sample. This analysis combines the magnification effect of strong galaxy-galaxy lensing with the high resolution of the Hubble Space Telesco…