Search Publications
Tests of stellar model atmospheres by optical interferometry. IV. VINCI interferometry and UVES spectroscopy of Menkar
Wolff, B.; Driebe, T.; Wittkowski, M. +3 more
Aims.We present coordinated near-infrared K-band interferometric and optical spectroscopic observations of the M 1.5 giant
GOYA Survey: U and B Number Counts in the Groth-Westphal Strip
Eliche-Moral, M. Carmen; Balcells, Marc; Cristóbal-Hornillos, David +3 more
We present U and B galaxy differential number counts from a field of ~900 arcmin2, based on GOYA Survey imaging of the HST Groth-Westphal strip. Source detection efficiency corrections as a function of the object size have been applied. A variation of the half-exposure image method has been devised to identify and remove spurious detect…
The X-ray binary 2S0114+650=LSI+65 010. A slow pulsar or tidally-induced pulsations?
Koenigsberger, G.; Canalizo, G.; Richer, M. G. +4 more
Context: .The X-ray source 2S0114+650=LSI+65 010 is a binary system containing a B-type primary and a low mass companion believed to be a neutron star. The system has three reported periodicities: the orbital period, P_orb∼11.6 days, X-ray flaring with P_flare∼2.7 h and a "superorbital" X-ray periodicity P_super=30.7 days.
Aims: .The objective…
Cloud Fragmentation and Proplyd-like Features in H II Regions Imaged by the Hubble Space Telescope
O'Dell, C. R.; De Marco, Orsola; Rubin, R. H. +2 more
We have analyzed Hubble Space Telescope ACS and WFPC2 new and archival images of eight H II regions to look for new protoplanetary disks (proplyds) similar to those found in the Orion Nebula. We find a wealth of features similar in size (although many are larger) to the bright cusps around the Orion Nebula proplyds. None of them, however, contains…
Mass Modeling of Abell 1689 Advanced Camera for Surveys Observations with a Perturbed Navarro-Frenk-White Model
Ford, H. C.; Jee, M. J.; Illingworth, G. D. +7 more
The combined resolution and sensitivity of the Advanced Camera for Surveys deep imaging provides the capability of high-accuracy lens modeling of Abell 1689. Originally based on the technique of Broadhurst and coworkers, our software is designed to provide a precise and efficient method of modeling cluster lenses without assumptions relating the l…
Application of a New Technique for Deriving Prominence Mass from SOHO EIT Fe XII (19.5 nm) Absorption Features
Gilbert, Holly R.; Holzer, Thomas E.; MacQueen, R. M. +1 more
In a previous study we developed a new technique for deriving prominence mass by observing how much coronal radiation in the Fe XII (19.5 nm) spectral line is absorbed by prominence material. In the present work we apply this new method, which allows us to consider the effects of both foreground and background radiation in our calculations, to a s…
The Warped Circumstellar Disk of HD 100546
Quillen, Alice C.
We propose that the two-armed spiral features seen in visible Hubble Space Telescope images of scattered light in HD 100546's circumstellar disk are caused by the illumination of a warped outer disk. A tilt of 6°-15° from the symmetry plane can cause the observed surface brightness variations, providing the disk is very twisted (highly warped) at …
XMM-Newton View of the z > 0 Warm-Hot Intergalactic Medium toward Markarian 421
Elvis, Martin; Williams, Rik J.; Nicastro, Fabrizio +1 more
The recent detection with Chandra of two warm-hot intergalactic medium (WHIM) filaments toward Mrk 421 by Nicastro et al. provides a measurement of the bulk of the ``missing baryons'' in the nearby universe. Since Mrk 421 is a bright X-ray source, it is also frequently observed by the XMM-Newton Reflection Grating Spectrometer (RGS) for calibratio…
Waves in Jupiter's atmosphere observed by the Cassini ISS and CIRS instruments
West, Robert A.; Porco, Carolyn C.; Achterberg, Richard K. +7 more
The Cassini Imaging Science Subsystem (ISS) and Composite Infrared Spectrometer (CIRS) reported a North Equatorial Belt (NEB) wave in Jupiter's atmosphere from optical images [Porco, C.C., and 23 colleagues, 2003. Science 299, 1541-1547] and thermal maps [Flasar, F.M., and 39 colleagues, 2004. Nature 427, 132-135], respectively. The connection bet…
Direct Measurements of Energetic Neutral Hydrogen in the Interplanetary Medium
Fedorov, A.; Barabash, S.; Lundin, R. +16 more
We present an analysis of hydrogen energetic neutral atoms (ENAs) measured by the ASPERA-3 instrument on board Mars Express. We focus on ENAs that have no Martian origin. The energy spectra of these ENAs are all very similar and can be fitted well by a two-component power law. The fluxes, integrated from 0.2 to 10 keV, vary between 5×103