Search Publications
Taking Advantage of the COS Time-tag Capability: Observations of Pulsating Hot DQ White Dwarfs and Discovery of a New One
Chayer, P.; Fontaine, G.; Bergeron, P. +2 more
We present an analysis of the ultraviolet light curves of five Hot DQ white dwarfs recently observed with the Cosmic Origins Spectrograph (COS) on board the Hubble Space Telescope (HST). These light curves were constructed by extracting the time-tag information from the FUV and NUV spectroscopic data. Single-color light curves were thus produced i…
Multispacecraft observations of chorus emissions as a tool for the plasma density fluctuations' remote sensing
Khotyaintsev, Yuri; Dudok de Wit, Thierry; Agapitov, Oleksiy +4 more
Discrete ELF/VLF chorus emissions are the most intense electromagnetic plasma waves that are observed in the radiation belts and in the outer magnetosphere of the Earth. They are assumed to propagate approximately along the magnetic field lines and are generated in source regions in the vicinity of the magnetic equator and in minimum B pockets in …
Locations of boundaries of outer and inner radiation belts as observed by Cluster and Double Star
Dandouras, I.; Cao, J.; Ganushkina, N. Yu +1 more
Cluster CIS ion spectrograms measured during the period of the recent solar minimum between April 2007 and June 2009, when Cluster was deep in the radiation belts with its perigee as close as L = 2, are analyzed. The analysis is complemented by Double Star TC-1 satellite data from HIA ion spectrograms on perigee passes during the period of May 15,…
The cosmic far-infrared background buildup since redshift 2 at 70 and 160 microns in the COSMOS and GOODS fields
Kneib, J. -P.; Aussel, H.; Le Floc'h, E. +10 more
Context. The cosmic far-infrared background (CIB) at wavelengths around 160 µm corresponds to the peak intensity of the whole extragalactic background light, which is being measured with increasing accuracy. However, the build up of the CIB emission as a function of redshift is still not well known.
Aims: Our goal is to measure the CIB …
Suzaku Metal Abundance Patterns in the Outflow Region of M 82 and the Importance of Charge Exchange
Gandhi, Poshak; Matsushita, Kyoko; Tamagawa, Toru +2 more
We performed spectral analysis of Suzaku data of the galactic disk and outflow regions of the starburst galaxy M 82. Thermal modeling of the central disk regions requires at least three temperature components. The Ly
Achieving Self-consistent Nonlinear Force-free Modeling of Solar Active Regions
Leka, K. D.; Wheatland, M. S.
A nonlinear force-free solution is constructed for the coronal magnetic field in NOAA solar active region (AR) 10953 based on a photospheric vector magnetogram derived from Hinode satellite observations on 2007 April 30, taking into account uncertainties in the boundary data and using improved methods for merging multiple-instrument data. The solu…
The relations between magnetospheric chorus and hiss inside and outside the plasmasphere boundary layer: Cluster observation
Zong, Qiugang; Xiao, Fuliang; Wang, Yongfu +3 more
Magnetospheric whistler mode emissions (chorus and hiss) can play an important role in acceleration and loss of energetic electrons by wave-particle interaction. Here we present a first report of two events in the simultaneous observations of chorus and hiss by the Cluster constellation. During the event of 30 August 2001, one spacecraft observed …
A Highly Magnified Supernova at z = 1.703 behind the Massive Galaxy Cluster A1689
Kneib, J. -P.; Dahle, H.; Lidman, C. +17 more
Our ability to study the most remote supernova explosions, crucial for the understanding of the evolution of the high-redshift universe and its expansion rate, is limited by the light collection capabilities of telescopes. However, nature offers unique opportunities to look beyond the range within reach of our unaided instruments thanks to the lig…
Comparative study of ion cyclotron waves at Mars, Venus and Earth
Russell, C. T.; Wei, H. Y.; Zhang, T. L. +1 more
Ion cyclotron waves are generated in the solar wind when it picks up freshly ionized planetary exospheric ions. These waves grow from the free energy of the highly anisotropic distribution of fresh pickup ions, and are observed in the spacecraft frame with left-handed polarization and a wave frequency near the ion's gyrofrequency. At Mars and Venu…
The Dust Properties of Two Hot R Coronae Borealis Stars and a Wolf-Rayet Central Star of a Planetary Nebula: In Search of a Possible Link
Sonneborn, G.; Gallagher, J. S.; Roman-Duval, J. +14 more
We present new Spitzer/IRS spectra of two hot R Coronae Borealis (RCB) stars, one in the Galaxy, V348 Sgr, and one lying in the Large Magellanic Cloud, HV 2671. These two objects may constitute a link between the RCB stars and the late Wolf-Rayet ([WCL]) class of central stars of planetary nebulae (CSPNe), such as CPD -56° 8032, that has little or…