Search Publications
Diffuse radio emission in a REFLEX cluster
Böhringer, H.; Govoni, F.; Giovannini, G. +2 more
Deep Very Large Array radio observations are presented for the REFLEX clusters RXC J0437.1{+}0043 and RXC J1314.4{-}2515. They are at similar distances and show similar X-ray luminosity, but they are quite different in X-ray structure. Indeed RXC J0437.1{+}0043 is regular and relaxed, whereas RXC J1314.4{-}2515 is characterized by substructure and…
Statistical survey of earthbound interplanetary shocks, associated coronal mass ejections and their space weather consequences
Tappin, S. J.; Howard, T. A.
A comprehensive statistical analysis of events relevant to space weather over the 80 month period from January 1998 to August 2004 is presented. A database has been constructed using data from instruments from the SOHO, ACE, WIND and GOES spacecraft, as well as ground magnetometer data. Parameters investigated include times and epochs of halo and …
On metal-deficient barium stars and their link with yellow symbiotic stars
Jorissen, A.; Udry, S.; Musaev, F. A. +2 more
This paper addresses the question of why metal-deficient barium stars are not yellow symbiotic stars (YSyS). Samples of (suspected) metal-deficient barium (mdBa) stars and YSyS have been collected from the literature, and their properties reviewed. It appears in particular that the barium nature of the suspected mdBa stars needs to be ascertained …
INTEGRAL detection of a long powerful burst from SLX 1735-269
Sunyaev, R.; Revnivtsev, M.; Lutovinov, A. +1 more
We present results of an analysis of the bursting behavior of the low mass X-ray binary system SLX 1735-269 during INTEGRAL observations of the Galactic Center region in 2003. Six type-I X-ray bursts were detected in total with one being much longer and more powerful then the others. A strong dependence of the burst recurrence time on the mass acc…
Solar limb faculae
Hirzberger, J.; Wiehr, E.
We observe solar limb faculae at an unprecedented spatial resolution with the new 1 m Swedish Solar Telescope SST on La Palma. Speckle-reconstructed images are used to study 4475 limb facular grains simultaneously in the 430 nm G-band and the 587.5±1.5 continuum up to only 1'' from the limb (cos θ=0.05). No systematic contrast decrease is found ev…
Metallicities of the β Cephei stars from low-resolution ultraviolet spectra
Niemczura, E.; Daszyńska-Daszkiewicz, J.
We derive basic stellar parameters (angular diameters, effective temperatures, metallicities) and interstellar reddening for all β Cephei stars observed during the IUE satellite mission, including those belonging to three open clusters. The parameters are derived by means of an algorithmic procedure of fitting theoretical flux distributions to the…
MHD simulation of the formation and propagation of multiple magnetic clouds in the heliosphere
Wang, S.; Wang, Y.; Zheng, H. +1 more
A multiple-magnetic-cloud (Multi-MC) structure formed by the overtaking of two successive coronal mass ejections (CMEs) in the heliosphere is studied by using a 2.5-D MHD simulation. This simulation illustrates the process of the formation and propagation of two identical CMEs, which are ejected with speeds of 400 km s-1 and 600 km s
The distance to the Pleiades. Main sequence fitting in the near infrared
Salaris, M.; Groenewegen, M. A. T.; Percival, S. M.
Hipparcos parallax measurements of stars in the Pleiades notoriously result in a cluster distance of 118 pc, which is approximately 10% shorter than the ``classical'' result obtained from earlier main sequence (MS) fitting studies. In an earlier paper we developed a purely empirical MS-fitting method in an attempt to address this problem. This wor…
The massive binary CPD - 41° 7742. II. Optical light curve and X-ray observations
Gosset, E.; Rauw, G.; Vreux, J. -M. +4 more
In the first paper of this series, we presented a detailed high-resolution spectroscopic study of
GRBs and the 511 keV emission of the Galactic bulge
Paul, J.; Cassé, M.; Parizot, E. +1 more
We consider the phenomenology of the 511 keV emission in the Galactic bulge, as recently observed by INTEGRAL, and propose a model in which the positrons are produced by gamma-ray bursts (GRB) associated with mini-starbursts in the central molecular zone (CMZ). We show that the positrons can easily diffuse across the bulge on timescales of ∼ 10