Search Publications
Towards a comprehensive picture of powerful quasars, their host galaxies and quasar winds at z ∼ 0.5
Zakamska, Nadia L.; Wylezalek, Dominika; Obied, Georges +1 more
Luminous type-2 quasars in which the glow from the central black hole is obscured by dust are ideal targets for studying their host galaxies and the quasars' effect on galaxy evolution. Such feedback appears ubiquitous in luminous obscured quasars where high-velocity-ionized nebulae have been found. We present rest-frame yellow-band (∼5000 Å) obse…
Spatial gradients of GCR protons in the inner heliosphere derived from Ulysses COSPIN/KET and PAMELA measurements
Gieseler, J.; Heber, B.
Context. During the transition from solar cycle 23 to 24 from 2006 to 2009, the Sun was in an unusual solar minimum with very low activity over a long period. These exceptional conditions included a very low interplanetary magnetic field (IMF) strength and a high tilt angle, which both play an important role in the modulation of galactic cosmic ra…
Cassini Imaging Science Subsystem observations of Titan's south polar cloud
West, R. A.; Rannou, P.; Lavvas, P. +5 more
In May of 2012 images of Titan obtained by the Cassini Imaging Science Subsystem (ISS) showed a newly-formed cloud patch near the southern pole. The cloud has unusual morphology and texture suggesting that it is formed by condensation at an altitude much higher than expected for any of the known organics in Titan's atmosphere. We measured the alti…
Venus' radar-bright highlands: Different signatures and materials on Ovda Regio and on Maxwell Montes
Treiman, Allan; Harrington, Elise; Sharpton, Virgil
Venus' highlands appear much brighter than its lowland plains in reflected radar, which has been explained by several conflicting hypotheses. We study this transition at higher spatial and elevation resolution than previously possible by combining Magellan synthetic aperture radar (SAR) images with Magellan SAR stereo elevations. We confirm that S…
Reconnection Properties of Large-scale Current Sheets During Coronal Mass Ejection Eruptions
Lynch, B. J.; Guidoni, S. E.; Edmondson, J. K. +1 more
We present a detailed analysis of the properties of magnetic reconnection at large-scale current sheets (CSs) in a high cadence version of the Lynch & Edmondson 2.5D MHD simulation of sympathetic magnetic breakout eruptions from a pseudostreamer source region. We examine the resistive tearing and break-up of the three main CSs into chains of X…
A physical scenario for the high and low X-ray luminosity states in the transitional pulsar PSR J1023+0038
D'Avanzo, P.; Campana, S.; Rea, N. +4 more
The binary system PSR J1023+0038 (J1023) hosts a neutron star and a low-mass companion. J1023 is the best studied transitional pulsar, alternating a faint eclipsing millisecond radio pulsar state to a brighter X-ray active state. At variance with other low-mass X-ray binaries, this active state reaches luminosities of only ~1034 erg s
Imaging Prominence Eruptions out to 1 AU
Howard, Russell A.; Linton, Mark G.; Wood, Brian E.
Views of two bright prominence eruptions trackable all the way to 1 AU are here presented, using the heliospheric imagers on the Solar TErrestrial RElations Observatory (STEREO) spacecraft. The two events first erupted from the Sun on 2011 June 7 and 2012 August 31, respectively. Only these two examples of clear prominence eruptions observable thi…
Luminosity Dependence and Redshift Evolution of Strong Emission-Line Diagnostics in Star-Forming Galaxies
Barger, A. J.; Cowie, L. L.; Songaila, A.
We examine the redshift evolution of standard strong emission-line diagnostics for Hβ-selected star-forming galaxies using the local SDSS sample and a new z=0.2{--}2.3 sample obtained from Hubble Space Telescope WFC3 grism and Keck DEIMOS and MOSFIRE data. We use the SDSS galaxies to show that there is a systematic dependence of the strong emissio…
Constraints on Photoionization Feedback from Number Counts of Ultra-faint High-redshift Galaxies in the Frontier Fields
Castellano, M.; Santini, P.; Merlin, E. +11 more
We exploit a sample of ultra-faint high-redshift galaxies (demagnified Hubble Space Telescope, HST, H 160 magnitude > 30) in the Frontier Fields clusters A2744 and M0416 to constrain a theoretical model for the UV luminosity function in the presence of photoionization feedback. The objects have been selected on the basis of accurate …
Quasi-periodic injections of relativistic electrons in Saturn's outer magnetosphere
Krupp, N.; Dougherty, M. K.; Roussos, E. +8 more
Quasi-periodic, short-period injections of relativistic electrons have been observed in both Jupiter's and Saturn's magnetospheres, but understanding their origin or significance has been challenging, primarily due to the limited number of in-situ observations of such events by past flyby missions. Here we present the first survey of such injectio…