Search Publications
SOHO/CDS observations of waves above the network
Curdt, W.; Rybák, J.; Gömöry, P. +2 more
We analyze temporal variations in the intensities and the Doppler shifts of He i 584.33 Å (chromosphere), O v 629.73 Å (transition region), and Mg ix 368.07 Å (corona) measured in and above chromospheric network near disk center with the Coronal Diagnostic Spectrometer (CDS) onboard the Solar and Heliospheric Observatory (SOHO). There is significa…
Encounters of the dust trails of comet 45P/Honda-Mrkos-Pajdusakova with Venus in 2006
Christou, A. A.; Vaubaillon, J.
Aims.We aim to investigate the dynamical fate of meteoroids ejected during past perihelion passages of comet 45P/Honda-Mrkos-Pajdusakova that intersect the orbit of Venus. Of particular interest is the possibility, borne of previous work, that a significant flux of these particles will reach the planet during early June and late August 2006, when …
A 110 MG cyclotron harmonic in the optical spectrum of RX J1554.2+2721
Szkody, P.; Schreiber, M. R.; Schwope, A. D.
We report the detection of a 110 MG cyclotron harmonic in the SDSS-spectrum of the magnetic cataclysmic variable (MCV) RX J1554.2+2721. This feature was noted earlier by others but remained unexplained. The wide spectral coverage of the new spectrum together with the earlier detection of a Zeeman split Lyα line in a field of 144 MG makes the ident…
Identification of a new short-period comet near the sun
Hönig, S. F.
We present the identification of comet C/1999 R1 (SOHO) with comet C/2003 R5 (SOHO). Both apparitions were only observed with the Solar and Heliospheric Observatory (SOHO) at distances smaller than 0.1 AU from the sun with the LASCO coronagraphs onboard the spacecraft. Although SOHO comets usually have poor orbital coverage, the 1999 and 2003 arcs…
A statistical study of SUMER spectral images: events, turbulence, and intermittency
Vial, J. -C.; Lemaire, P.; Buchlin, E.
We analyze a series of full-Sun observations performed with the SoHO/SUMER instrument between March and October 1996. Some parameters (radiance, shift and width) of the S vi 93.3 nm , S vi 94.4 nm , and Ly \varepsilon line profiles were computed on board. Radiances and line-of-sight velocities in a large central region of the Sun are studied stati…
A search for stellar X-ray sources in the Sagittarius and Carina dwarf galaxies. I. X-ray observations
Ramsay, G.; Wu, K.
ROSAT observations found no convincing evidence for X-ray sources located in local dwarf spheroidal galaxies (dSph). Now with more sensitive instruments on board Chandra and XMM-Newton we can reach fainter luminosity levels. We report on an observation of the Sagittarius (Sgr) dSph made using Chandra and an observation of the Carina (Car) dSph mad…
The globular cluster system of NGC 5846 revisited: colours, sizes and X-ray counterparts
Santiago, B. X.; Pastoriza, M. G.; Chies-Santos, A. L. +1 more
Context.NGC 5846 is a giant elliptical galaxy with a previously well studied globular cluster system (GCS), known to have a bimodal colour distribution with a remarkably high red fraction.
Aims.Here we revisit the central galaxy regions searching for new globular cluster (GC) candidates, and measure magnitudes, colours and sizes for them. We al…
Resonance-enhanced two-photon ionization (RETPI) of Si II and an anomalous, variable intensity of the λ1892 Si III] line in the Weigelt blobs of η Carinae
Johansson, S.; Hartman, H.; Letokhov, V. S.
Context: .The Si III] 1892 Å intercombination line shows an anomalously high intensity in spectra of the radiation-rich Weigelt blobs in the vicinity of Eta Carinae. The line disappears during the 100 days long spectral events occurring every 5.5 years.
Aims: .The aim is to investigate whether resonance-enhanced two-photon ionization (RETPI) i…
Identification of four RXTE Slew Survey sources with nearby luminous active galactic nuclei
Revnivtsev, M.; Sazonov, S.; Churazov, E. +1 more
Based on RXTE scans and observations with the SWIFT/XRT telescope and INTEGRAL observatory, we report the identification of four X-ray sources discovered during the RXTE Slew Survey of the |b|>10° sky with nearby (z∼0.017-0.098) luminous (L2-10~keV∼ 5× 1042-1044 erg s-1) active galactic nuclei. Two of…
Correlated X-ray spectral and timing variability of the Be/X-ray binary V0332+53/BQ Camelopardalis during a type II outburst
Reig, P.; Martínez-Núñez, S.; Reglero, V.
Context: .After more than 15 years of quiescence the Be/X-ray binary V0332+53 underwent a giant outburst in December 2004.Aims.We have investigated the timing properties of the source in correlation with its spectral states as defined by different positions in the colour-colour diagram. Methods.We have used RXTE and INTEGRAL light curves to obtain…