Search Publications
A Deep Hubble Space Telescope H-Band Imaging Survey of Massive Gas-rich Mergers
Lutz, D.; Genzel, R.; Tacconi, L. J. +6 more
We report the results from a deep HST NICMOS H-band imaging survey of a carefully selected sample of 33 luminous, late-stage galactic mergers at z<0.3. This program is part of QUEST (Quasar/ULIRG Evolutionary Study). Signs of a recent galactic interaction are seen in all of these objects, including all seven IR-excess Palomar-Green (PG) QSOs in…
Fundamental Properties of O-Type Stars
Hubeny, Ivan; Heap, Sara R.; Lanz, Thierry
We present a comprehensive analysis of high-resolution, far-ultraviolet HST STIS, FUSE, and optical spectra of 18 O stars in the Small Magellanic Cloud. Our analysis is based on the OSTAR2002 grid of NLTE metal-line-blanketed model atmospheres calculated with our code TLUSTY. We systematically explore and present the sensitivity of various UV and …
Shedding New Light on the 3C 273 Jet with the Spitzer Space Telescope
Cheung, C. C.; Takahashi, Tadayuki; Van Duyne, Jeffrey +7 more
We have performed infrared imaging of the jet of the quasar 3C 273 at wavelengths of 3.6 and 5.8 µm with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. When combined with the radio, optical, and X-ray measurements, the IRAC photometry of the X-ray-bright jet knots clearly shows that the optical emission is dominated by the …
Multi-wavelength study of coronal waves associated with the CME-flare event of 3 November 2003
Magdalenić, J.; Temmer, M.; Vršnak, B. +4 more
The large flare/CME event that occurred close to the west solar limb on 3 November 2003 launched a large-amplitude large-scale coronal wave that was observed in Hα and Fe xii 195 Å spectral lines, as well as in the soft X-ray and radio wavelength ranges. The wave also excited a complex decimeter-to-hectometer type II radio burst, revealing the for…
A catalogue of close binaries located in the δ Scuti region of the Cepheid instability strip
Demircan, O.; Soydugan, F.; Soydugan, E. +1 more
A catalogue of close eclipsing binary systems (detached and semidetached) with at least one of the components located in the δ Scuti region of the Cepheid instability strip is presented. The positions of the stars in the instability strip are determined by their accurate temperatures and luminosities. Observationally detected binaries (20 semideta…
The First INTEGRAL AGN Catalog
Gehrels, N.; Shrader, C. R.; Beckmann, V. +1 more
We present the first INTEGRAL AGN catalog, based on observations performed from launch of the mission in 2002 October until 2004 January. The catalog includes 42 AGNs, of which 10 are Seyfert 1, 17 are Seyfert 2, and 9 are intermediate Seyfert 1.5. The fraction of blazars is rather small, with five detected objects, and only one galaxy cluster and…
Rapid Changes of Photospheric Magnetic Fields around Flaring Magnetic Neutral Lines
Wang, Haimin
In this paper we study the short-term evolution of magnetic fields associated with five flares in δ-sunspots. We concentrate on the analysis of the magnetic gradient along the flaring neutral lines (NLs). Obvious changes of the magnetic gradient occurred immediately and rapidly following the onset of each flare. A rapid gradient increase was found…
Measuring the Average Evolution of Luminous Galaxies at z < 3: The Rest-Frame Optical Luminosity Density, Spectral Energy Distribution, and Stellar Mass Density
van Dokkum, Pieter G.; Franx, Marijn; Labbé, Ivo +11 more
We present the evolution of the volume-averaged properties of the rest-frame optically luminous (LV>3×1010 h-270 Lsolar) galaxy population to z~3, determined from four disjoint deep fields. We characterize their rest-frame UV through optical properties via the mean SED. To measure evolution…
Searching for Low Surface Brightness Galaxies in the Hubble Ultra Deep Field: Implications for the Star Formation Efficiency in Neutral Gas at z~3
Chen, Hsiao-Wen; Wolfe, Arthur M.
Applying the Kennicutt-Schmidt law to damped Lyα absorption systems (DLAs), we predict that 3% of the sky should be covered with extended objects brighter than µV~28.4 mag arcsec-2, if DLAs at redshift z=[2.5, 3.5] undergo in situ star formation. We test this hypothesis by searching the Hubble Ultra Deep Field (UDF) F60…
Charge-transfer induced EUV and soft X-ray emissions in the heliosphere
Lallement, R.; Izmodenov, V.; Quémerais, E. +4 more
Aims.We study the EUV/soft X-ray emission generated by charge transfer between solar wind heavy ions and interstellar neutral atoms and variations of the X-ray intensities and spectra with the line of sight direction, the observer location, the solar cycle phase and the solar wind anisotropies, and a temporary enhancement of the solar wind similar…