Search Publications
Subarcsecond Mid-Infrared Observations of NGC 6240: Limitations of Active Galactic Nucleus-Starburst Power Diagnostics
Egami, E.; Matthews, K.; Soifer, B. T. +3 more
In order to examine the relative importance of powerful starbursts and Compton-thick active galactic nuclei (AGNs) in NGC 6240, we have obtained mid-infrared images and low-resolution spectra of the galaxy with subarcsecond spatial resolution using the Keck telescopes. Despite the high spatial resolution (~200 pc) of our data, no signature of the …
Success rate of predicting the heliospheric magnetic field polarity with Michelson Doppler Imager (MDI) synoptic charts
Liu, Y.; Hoeksema, J. T.; Scherrer, P. H. +1 more
The photospheric and heliospheric magnetic fields have been continuously observed at the L1 point by the Michelson Doppler Imager (MDI) on the Solar and Heliospheric Observatory (SOHO) and Wind and the Advanced Composition Explorer (ACE) spacecraft since 1996. The combined observations of the photospheric and heliospheric magnetic fields make it p…
Automatic classification of eclipsing binaries light curves using neural networks
Sarro, L. M.; Sánchez-Fernández, C.; Giménez, Á.
In this work we present a system for the automatic classification of the light curves of eclipsing binaries. This system is based on a classification scheme that aims to separate eclipsing binary systems according to their geometrical configuration in a modified version of the traditional classification scheme. The classification is performed by a…
Characterization of zonal winds in the stratosphere of Titan with UVES: 2. Observations coordinated with the Huygens Probe entry
Livengood, T.; Kostiuk, T.; Witasse, O. +8 more
The Huygens Probe has successfully entered Titan's atmosphere and landed on its surface on 14 January 2005. With the aim of characterizing the zonal wind flow in Titan's stratosphere close to the time of entry, coordinated observations were carried out at the Very Large Telescope on the nights of 7, 12, 14, and 15 January. As in our previous inves…
XMM-Newton observations of the Seyfert 1 AGN H0557-385
Page, M. J.; Branduardi-Raymont, G.; Blustin, A. J. +1 more
We present XMM-Newton observations of the Seyfert 1 active galactic nucleus (AGN) H0557-385. We have conducted a study into the warm absorber present in this source, and using high-resolution Reflection Grating Spectrometer (RGS) data we find that the absorption can be characterized by two phases: a phase with log ionization parameter ξ of 0.50 (w…
Calibration of space instrumentation with synchrotron radiation
Richter, M.; Gottwald, A.; Scholze, F. +2 more
For many years, synchrotron radiation as emitted from electron storage rings has been established as a versatile tool for photon metrology in the spectral range from ultraviolet radiation to X-rays. In particular, various radiometric techniques have been developed and applied for the calibration of space instrumentation. In this context, the prese…
Evidence for an Hesperian-aged South Circum-Polar Lake Margin Environment on Mars
Head, James W.; Dickson, James
A broad pitted plain and an elongated low rise occur near the south pole of Mars between a region of major cavi (Cavi Angusti) and a regionally smooth and broad valley (Argentea Planum). Viking, Mars Global Surveyor (MGS), and Odyssey data reveal a densely pitted plain covering ∼6750 km 2, and containing >300 irregularly shaped, stee…
The Outskirts of Spiral Galaxies: Evidence for Multiple Stellar Populations
Mouhcine, M.
We present an analysis of the metallicity distribution functions of fields projected along the minor axis for a sample of inclined spiral galaxies in order to search for evidence of the presence of multiple stellar populations. In all cases, with very high confidence levels, the stellar populations appear to have asymmetric metallicity distributio…
Very Cold and Massive Cores near ISOSS J18364-0221: Implications for the Initial Conditions of High-Mass Star Formation
Krause, O.; Birkmann, S. M.; Lemke, D.
We report the discovery of two very cold and massive molecular cloud cores in the region ISOSS J18364-0221. The object has been identified by a systematic search for very early evolutionary stages of high-mass stars using the 170 µm ISOPHOT Serendipity Survey (ISOSS). Submillimeter continuum and molecular line measurements reveal two compact…
An X-ray bright ERO hosting a type 2 QSO
Page, M. J.; Akiyama, M.; Carrera, F. J. +8 more
We present the XMM-Newton and the optical-VLT spectra along with the optical and the near-infrared photometric data of one of the brightest X-ray (F2{-10 keV}∼10-13 erg s-1 cm-2) extremely red objects (R-K≥5) discovered so far. The source, XBS J0216-0435, belongs to the XMM-Newton Bright Serendipitous Su…