Search Publications
Accurate photometric light curves of the lensed components of Q2237+0305 derived with an optimal image subtraction technique: Evidence for microlensing in image A
Surdej, J.; Libbrecht, C.; Moreau, O. +1 more
Using an optimal image subtraction technique, we have derived the V and R light curves of the four lensed QSO components of Q2237+0305 from the monitoring CCD frames obtained by the GLITP collaboration with the 2.6 m NOT telescope in 1999/2000 (Alcalde et al. 2002). We give here a detailed account of the data reduction and analysis and of the erro…
Outbursts on normal stars. FH Leo misclassified as a novalike variable
Santos, N. C.; Schmidtobreick, L.; Israelian, G. +1 more
We present high resolution spectroscopy of the common proper motion system FH Leo (components HD 96273 and BD+07 2411B), which has been classified as a novalike variable due to an outburst observed by Hipparcos, and we present and review the available photometry. We show from our spectra that neither star can possibly be a cataclysmic variable, in…
Systematic motions in the galactic plane found in the Hipparcos catalogue using Herschel's Method
Vieira, K.; Abad, C.
Two motions in the galactic plane have been detected and characterized, based on the determination of a common systematic component in Hipparcos catalogue proper motions. The procedure is based only on positions, proper motions and parallaxes, plus a special algorithm which is able to reveal systematic trends. Our results come from two stellar sam…
Cosmic Shear from STIS pure parallels. III. Analysis of Cycle 9 pure parallels
Fosbury, R. A. E.; Schneider, P.; Erben, T. +4 more
Following the detection of a cosmic shear signal at the 30'' scale using archival parallel data from the STIS CCD camera onboard HST in the previous paper of this series, we analyzed a larger data set obtained from an HST GO pure parallel program. Although this data set is considerably larger than the one analyzed previously, we do not obtain a si…
The X-ray activity of the slowly rotating G giant δ CrB
Gondoin, P.
δ CrB is a single G giant whose distinctive characteristics include an X-ray luminosity exceptionally high for a slowly rotating star. δ CrB was observed in March 2003 by the {XMM{-}Newton} observatory. The X-ray spectra of δ CrB are described by a MEKAL plasma model with two components at 6.5 ×106 K and 107 K. Series of line…
The peculiar galaxy Mkn 298 revisited with integral field spectroscopy
Ciroi, S.; Rafanelli, P.; Radovich, M. +3 more
Spectroscopic and imaging data of the peculiar galaxy Mkn 298 are presented. Narrow-band Hα and broad-band R images are used to study the star formation rate in the galaxy and its morphology, which is typical of a merging system. Long-slit and integral field spectra are used to assess the kinematics of gas and stars, and the nature of the ionizing…
Discovery of multiple ultra-luminous X-ray sources in the galaxy KUG 0214-057
Akiyama, M.; Watson, M. G.; Roberts, T. P. +1 more
We report the serendipitous discovery of several unresolved X-ray sources lying in the prominent spiral arms of the galaxy
XMM-Newton observation of 4U 1543-475: The X-ray spectrum of a stellar-mass black-hole at low luminosity
Mereghetti, S.; La Palombara, N.
We report the results of an observation of the galactic black-hole binary 4U 1543-475 performed by XMM-Newton on 2002 August 18, about two months after the start of an outburst detected by RXTE. Despite the relatively low flux of the source, corresponding to a luminosity LX∼ 4× 1034 erg s-1∼ 10-5 LE…
Heliospheric energetic neutral atoms as a means to determine the anomalous cosmic ray spectrum at the termination shock
Hsieh, K. C.; Hilchenbach, M.; Czechowski, A.
We demonstrate the possibility of deriving the anomalous cosmic ray (ACR) spectrum at the solar wind termination shock and the strength of the shock using energetic neutral H and He atoms (ENA) measurements at 1 AU. Assuming that the energetic neutral atoms detected by CELIAS/HSTOF on board SOHO are of ACR origin, we consider χ2 fits to…
Observations of the companion to the pulsar PSR B1718-19. The role of tidal circularisation
van Kerkwijk, M. H.; Janssen, T.
We present optical and infrared observations taken with the Very Large Telescope of the eclipsing binary pulsar system