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Hot protons in the inner corona and their effect on the flow properties of the solar wind

Habbal, Shadia R.; Hollweg, Joseph V.; Esser, Ruth +1 more

Following recent observations which indicate the presence of extremely high flow speeds in the inner corona, 700-800kms^-1 below 10R_S, and the possible presence of very high proton temperatures, 3×10⁶<=T_p<=8.5×10⁶K, we present a parameter study which shows that if the high proton temperat…

Observations of the Hubble Deep Field with the Infrared Space Observatory - I. Data reduction, maps and sky coverage

Elbaz, D.; Danese, L.; Franceschini, A. +16 more

We present deep imaging at 6.7 and 15 mu from the CAM instrument on the Infrared Space Observatory (ISO), centred on the Hubble Deep Field (HDF). These are the deepest integrations published to date at these wavelengths in any region of sky. We discuss the observational strategy and the data reduction. The observed source density appears to approa…

Observations of GRB 970228 and GRB 970508 and the Neutron Star Merger Model

Livio, Mario; Bond, Howard E.; Kouveliotou, Chryssa +6 more

We present the discovery observations for the optical counterpart of the gamma -ray burster GRB 970508 and discuss its light curve in the context of the fireball model. We analyze the HST data for this object and conclude that any underlying galaxy must be fainter than R=25.5 . We also present a detailed analysis of the HST images of GRB 970228, f…

Time-Resolved Ultraviolet Observations of the Globular Cluster X-Ray Source in NGC 6624: The Shortest Known Period Binary System

Anderson, Scott F.; Margon, Bruce; Deutsch, Eric W. +2 more

Using the Faint Object Spectrograph (FOS) aboard the Hubble Space Telescope (HST), we have obtained the first time-resolved spectra of the King et al. (1993) ultraviolet-bright counterpart to the 11 minute binary X-ray source in the core of the globular cluster NGC 6624. This object cannot be readily observed in the visible, even from HST, because…

Radiometric calibration of SUMER: refinement of the laboratory results under operational conditions on SOHO

Wilhelm, Klaus; Schühle, Udo; Curdt, Werner +3 more

The broad line region of narrow-line Seyfert 1 galaxies.

Mas-Hesse, J. M.; Rodriguez-Pascual, P. M.; Santos-Lleo, M.

We have analyzed new and archival IUE observations of narrow-line Seyfert 1 galaxies (NLS1) in order to revise the ultraviolet (UV) properties of this sub-group of Active Galactic Nuclei (AGN). We have found broad wings in the strongest UV emission lines, ruling out the hypothesis that there is no broad line emission region in this type of objects…

Evidence of a Thermonuclear Runaway and Proton-Capture Material on a White Dwarf in a Dwarf Nova

Szkody, Paula; Sion, Edward M.; Hubeny, Ivan +3 more

We present Hubble Space Telescope Goddard High-Resolution Spectrograph G160M spectra of the white dwarf in VW Hydri, exposed during quiescence, 1 month after the end of a normal dwarf nova outburst. Our spectra, covering the wavelength interval 1236-1272 Å, were obtained at orbital phase 0.06-1.60 they reveal strong photospheric Si II λλ1260, 1265…

Hubble Space Telescope Observations of the Middle-aged Pulsar 0656+14

Córdova, F. A.; Pavlov, G. G.; Welty, A. D.

Multiwavelength spectral observations of middle-aged (τ~10⁴-10⁶ yr) isolated pulsars enable one in principle to separate thermal radiation emitted from the neutron star surface and nonthermal radiation from its magnetosphere. We have previously detected the middle-aged radio and soft X-ray pulsar 0656+14 with the Hubble Space…

A jet-cloud interaction in 3C 34 at redshift z=0.69

Best, P. N.; Rottgering, H. J. A.; Longair, M. S.

We report the detection of a strong jet-cloud interaction at a distance of 120 kpc from the nucleus of the radio galaxy 3C 34, which has redshift z=0.69. Hubble Space Telescope images of the radio galaxy show a long narrow region of blue emission orientated along the radio axis and directed towards a radio hotspot. The William Herschel Telescope h…

The Shock and Extended Remnant around the Crab Nebula

Hester, J. Jeff; Sankrit, Ravi

The [O III] ``skin'' around the Crab Nebula was shown by Hester et al. to be the Rayleigh-Taylor (R-T)-unstable interface between the synchrotron nebula and swept-up ejecta from the supernova explosion. Unlike the bright photoionized filaments, this skin is most easily understood as the cooling region behind a shock driven into an extended remnant…