Search Publications
X-ray Emission from the FU Orionis Star V1735 Cygni
Skinner, Stephen L.; Güdel, Manuel; Sokal, Kimberly R. +1 more
The variable star V1735 Cyg (=Elias 1-12) lies in the IC 5146 dark cloud and is a member of the class of FU Orionis objects whose dramatic optical brightenings are thought to be linked to episodic accretion. We report the first X-ray detections of V1735 Cyg and a deeply embedded class I protostar lying 24'' to its northeast. X-ray spectra obtained…
Ten More New Sightlines for the Study of Intergalactic Helium, and Hundreds of Far-Ultraviolet-Bright Quasars, from the Sloan Digital Sky Survey, Galaxy Evolution Explorer, and Hubble Space Telescope
Anderson, Scott F.; Schneider, Donald P.; York, Donald G. +4 more
Absorption along quasar sightlines remains among the most sensitive direct measures of He II reionization in much of the intergalactic medium (IGM). Until recently, fewer than a half-dozen unobscured quasar sightlines suitable for the He II Gunn-Peterson test were known; although these handful demonstrated great promise, the small sample size limi…
Super-Hard X-Ray Emission from η Carinae Observed with Suzaku
Hamaguchi, Kenji; Ishida, Manabu; Tsujimoto, Masahiro +4 more
We present the Suzaku results of η Carinae in the 5-50keV range conducted twice around the apastron in 2005 August for 50ks and in 2006 February for 20ks. The X-ray Imaging Spectrometer (XIS) produced hard (5-12keV) band spectra, resolving K shell lines from highly ionized Fe and Ni. The Hard X-ray Detector yielded a significant detection in the s…
Recurrent CIR-accelerated ions observed by STEREO SEPT
Gómez-Herrero, R.; Heber, B.; Müller-Mellin, R. +3 more
Fast solar wind streams originating from coronal holes interact with the preceding slow wind, leading to the formation of corotating interaction regions (CIRs) in the interplanetary medium. Near solar minimum CIR-associated shocks become the dominant source of energetic ion increases observed near 1 AU in the energy range between some tens of keV/…
Plasma transport in the magnetotail lobes
Haaland, S.; Lybekk, B.; Pedersen, A. +4 more
The Earth's magnetosphere is populated by particles originating from the solar wind and the terrestrial ionosphere. A substantial fraction of the plasma from these sources are convected through the magnetotail lobes. In this paper, we present a statistical study of convective plasma transport through the Earth's magnetotail lobes for various geoma…
A redetermination of the ice/vapor ratio of Enceladus’ plumes: Implications for sublimation and the lack of a liquid water reservoir
Kieffer, Susan W.; Lu, Xinli; McFarquhar, Greg +1 more
The discovery of plumes of H 2O vapor and ice particles erupting from the south pole of Enceladus, the tiny frigid satellite of Saturn, sparked controversy over whether these plumes are produced by boiling, or by sublimation with subsequent recondensation of the sublimated vapor [Porco, C.C., Helfenstein, P., Thomas, P.C., Ingersoll, A.…
Paleolakes, paleofloods, and depressions in Aurorae and Ophir Plana, Mars: Connectivity of surface and subsurface hydrological systems
Di Achille, Gaetano; Komatsu, Goro; Rossi, Angelo Pio +3 more
The plains of Aurorae and Ophir in the equatorial region of Mars display geomorphic evidence indicative of extensive but generally short-lived paleohydrological processes. Elaver Vallis in Aurorae Planum south of Ganges Chasma is an outflow channel system >180 km long, and here inferred to have formed by cataclysmic spillover flooding from a pa…
Spectroscopic binaries among Hipparcos M giants. III. The eccentricity - period diagram and mass-transfer signatures
Jorissen, A.; Famaey, B.; Frankowski, A. +1 more
Context: This paper is the third one in a series devoted to studying the properties of binaries involving M giants.
Aims: We use a new set of orbits to construct the first (e - log P) diagram of an extensive sample of M giant binaries, to obtain their mass-function distribution, and to derive evolutionary constraints for this class of binaries…
X-ray emission from GPS and CSS sources
Siemiginowska, A.
Many X-ray observations of GigaHertz Peaked Spectrum and Compact Steep Spectrum sources have been made with Chandra X-ray Observatory and XMM-Newton Observatory over the last few years. The X-ray spectra contribute the important information to the total energy distribution of the compact radio sources. In addition the spatial resolution of Chandra…
Absorption of p Modes by Thin Magnetic Flux Tubes
Birch, Aaron C.; Jain, Rekha; Hindman, Bradley W. +1 more
We study the interaction between p modes and the many magnetic fibrils that lace the solar convection zone. In particular, we investigate the resulting absorption of p-mode energy by the fibril magnetic field. Through mechanical buffeting, the p modes excite tube waves on the magnetic fibrils—in the form of longitudinal sausage waves and transvers…