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Non-radial pulsations in the γ Doradus star HD 195068

Mathias, P.; Jankov, S.; Chapellier, E. +2 more

We present high resolution spectroscopic observations of the γ Doradus star HD 195068. About 230 spectra were collected over 2 years. Time series analysis performed on radial velocity data shows a main peak at 1.61 d^-1 , a frequency not yet detected in photometry. The Hipparcos photometric 1.25 d^-1 frequenc…

INTEGRAL and RXTE power spectra of Cygnus X-1

Nowak, M. A.; Wilms, J.; Pottschmidt, K. +3 more

We evaluate 0.03 20 Hz power spectra of the bright black hole binary Cyg X-1 obtained from non-deconvolved INTEGRAL-ISGRI event data. The ISGRI power spectra are compared to contemporary RXTE-PCA ones in the same hard X-ray energy band of 15 70 keV. They agree well in shape. Since the ISGRI power spectrum of Cyg X-1 is not background corrected it …

The color signature of the transit of HD 209458: discrepancies between stellar atmospheric models and observations

Tingley, B.; Thurl, C.; Sackett, P.

Exoplanetary transits produce a double-horned color signature that is distinct from both binaries and blends and can thus be used to separate exoplanets from false positives in transit searches. Color photometry with precision sufficient to detect this signal in transits of HD 209458 is available in the literature. Analysis of these observations r…

Deviations from passive evolution - star formation and the ultraviolet excess in z~ 1 radio galaxies

Inskip, K. J.; Best, P. N.; Longair, M. S.

Galaxy colours are determined for two samples of 6C and 3CR radio sources at z~ 1, differing by a factor of ~6 in radio power. Corrections are made for emission-line contamination and the presence of any nuclear point source, and the data analysed as a function of both redshift and the radio source properties. The galaxy colours are remarkably sim…

Morphological classification of nearby galaxies based on asymmetry and luminosity concentration

Doi, M.; Shimasaku, K.; Okamura, S. +2 more

We investigate the behaviour of the asymmetry parameter A as a morphological parameter using a `volume-limited' sample of 349 galaxies (distance <=25Mpc,M_V<=-18.5mag) and a larger magnitude-limited sample of 707 nearby galaxies. We confirm the correlation of A with morphological type. The late-type galaxies (Sdm, Sm and Im) have l…

High Resolution and Broad Band Spectra of Low Mass X-ray Binaries: a Comparison between Black Holes and Neutron Stars

Iaria, Rosario; Di Salvo, Tiziana; Burderi, Luciano +1 more

A common question about compact objects in high energy astrophysics is whether it is possible to distinguish black hole from neutron star systems with some other property that is not the mass of the compact object. Up to now a few characteristics have been found which are typical of neutron stars (like quasi periodic oscillations at kHz frequencie…

Cluster observations of a structured magnetospheric cusp

Balogh, A.; Fazakerley, A. N.; André, M. +8 more

On 18 April 2002 the Cluster spacecraft crossed through the northern outer magnetospheric cusp region during 16:25-17:55 UT when the solar wind dynamic pressure was rather low (<2 nPa) and IMF B_z was more negative than IMF B_y. The Cluster data from the FGM, CIS, PEACE, EFW, WHISPER and STAFF instruments reveal that the cus…

Double-Probe Measurements in Cold Tenuous Space Plasma Flows

Eriksson, A. I.; Engwall, E.

Anglo-Australian Telescope Imaging and Microslit Spectroscopy in the Southern Hubble Deep Field

Glazebrook, Karl; Mann, Robert G.; Verma, Aprajita +3 more

We present a deep photometric (B- and R-band) catalog and an associated spectroscopic redshift survey conducted in the vicinity of the Hubble Deep Field-South. The spectroscopy yields 53 extragalactic redshifts in the range 0<z<1.4, substantially increasing the body of spectroscopic work in this field to over 200 objects. The targets are sel…

A multi-wavelength study of the IRAS Deep Survey galaxy sample. I. Optical observations. The redshift distribution

Aussel, H.; de Zotti, G.; Mazzei, P. +2 more

Context: The IRAS Deep Survey (IDS) of the North Ecliptic Pole region remains one of the deepest complete far-infrared-selected galaxy samples available. ISOCAM observations in the LW3 filter (12-18 µm) of 3.2 arcmin × 3.2 arcmin fields centered on the nominal positions of 94 out of the 98 IDS sources yielding 116 ISOCAM detections. The resu…