Search Publications
The Timing of Flares Associated with the Two Dynamical Types of Solar Coronal Mass Ejections
Golub, L.; Zhang, M.; Burkepile, J. +1 more
In this Letter, we consider a sample of Transition Region and Coronal Explorer flare-associated solar coronal mass ejections (CMEs) and study the timing behavior of the flares associated with fast or slow CMEs. We find that flares associated with fast CMEs tend to happen within half an hour of the CME onsets, while the timing of flares associated …
The Broadband Afterglow of GRB 980329
Price, P. A.; Harrison, F. A.; Galama, T. J. +15 more
We present radio observations of the afterglow of the bright γ-ray burst GRB 980329 made between 1 month and several years after the burst, a reanalysis of previously published submillimeter data, and late-time optical and near-infrared (NIR) observations of the host galaxy. From the absence of a spectral break in the optical/NIR colors of the hos…
Solar and Heliospheric Observatory Ultraviolet Coronagraph Spectrometer and Yohkoh Soft X-Ray Telescope Observations of the High-Temperature Corona above an Active Region Complex
Fineschi, Silvano; Raymond, John C.; Li, Jing +4 more
We present the results of Solar and Heliospheric Observatory Ultraviolet Coronagraph Spectrometer (SOHO/UVCS) and Yohkoh Soft X-Ray Telescope (SXT) observations above an active region complex (AR 8194, 8195, and 8198) at the southeast limb on 1998 April 6-7. This active region complex appears to be the base of a small streamer seen by the Large An…
XMM-Newton Detection of Hard X-Ray Emission in the Nitrogen-Type Wolf-Rayet Star WR 110
Skinner, Stephen L.; Zhekov, Svetozar A.; Güdel, Manuel +1 more
We have used the excellent sensitivity of XMM-Newton to obtain the first high-quality X-ray spectrum of a Wolf-Rayet (W-R) star that is not known to be a member of a binary system. Our target, the nitrogen-type star WR 110 (HD 165688), was also observed and detected with the Very Large Array at four different frequencies. The radio flux density in…
Giant low surface brightness haloes in distant radio galaxies: USS0828+193
Pentericci, L.; Humphrey, A.; Villar-Martín, M. +5 more
We present results on the spectroscopic study of the ionized gas in the high-redshift radio galaxy USS0828+193 at z= 2.57. Thanks to the high signal-to-noise (S/N) ratio of the emission lines in the Keck spectrum, we have been able to perform a detailed kinematic study by means of the spectral decomposition of the emission line profiles. This stud…
Observations of the Hubble Deep Field South with the Infrared Space Observatory - II. Associations and star formation rates
Oliver, Seb; Elbaz, David; Franceschini, Alberto +15 more
We present results from a deep mid-infrared survey of the Hubble Deep Field South (HDF-S) region performed at 6.7 and 15µm with the ISOCAM instrument on board the Infrared Space Observatory (ISO ). We find reliable optical/near-infrared associations for 32 of the 35 sources detected in this field by Oliver et al. (Paper I): eight of them are…
An XMM-Newton observation of the Lagoon Nebula and the very young open cluster NGC 6530
Gosset, E.; Corcoran, M. F.; Blomme, R. +5 more
We report the results of an XMM-Newton observation of the Lagoon Nebula (M 8). Our EPIC images of this region reveal a cluster of point sources, most of which have optical counterparts inside the very young open cluster NGC 6530. The bulk of these X-ray sources are probably associated with low and intermediate mass pre-main sequence stars. One of …
The Apparent Host Galaxy of PKS 1413+135: Hubble Space Telescope, ASCA, and Very Long Baseline Array Observations
Perlman, Eric S.; Stocke, John T.; Sugiho, Masahiko +5 more
PKS 1413+135 (z=0.24671) is one of very few radio-loud active galactic nuclei (AGNs) with an apparent spiral host galaxy. Previous authors have attributed its nearly exponential infrared cutoff to heavy absorption but have been unable to place tight limits on the absorber or its location in the optical galaxy. In addition, doubts remain about the …
An XMM-Newton observation of Ton S180: constraints on the continuum emission in ultrasoft Seyfert galaxies
Brandt, W. N.; Vaughan, S.; Fabian, A. C. +3 more
We present an XMM-Newton observation of the bright, narrow-line, ultrasoft type 1 Seyfert galaxy Ton S180. The 0.3-10 keV X-ray spectrum is steep and curved, showing a steep slope above 2.5 keV (Γ~ 2.3) and a smooth, featureless excess of emission at lower energies. The spectrum can be adequately parametrized using a simple double power-law model.…
The X-Ray Source at the Center of the Cassiopeia A Supernova Remnant
Tiengo, A.; Mereghetti, S.; Israel, G. L.
We present the first results of an XMM-Newton observation of the central X-ray source in the Cas A supernova remnant. The spectrum can be fitted equally well with an absorbed steep power law (αph~3, NH~1.5×1022 cm-2) or with a bremsstrahlung with temperature kT~2.4 keV and NH~1022 c…