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Photographic observations of solar system bodies at the Engelhardt astronomical observatory
Rizvanov, N.; Nefedjev, Ju.
We describe a large database of photographic observations of Solar System bodies obtained at the Engelhadt Astronomical Observatory (EnAO). We give a brief description of the methods of observations and the accuracy of their reduction with the PPM and Tycho-2 catalogues. The photographic positions of the major planets, except Jupiter, are in the s…
Search for radiative pumping lines of OH masers. I. The 34.6 m absorption line towards 1612 MHz OH maser sources
Szczerba, R.; Sobolev, A. M.; Chen, P. S. +1 more
The 1612 MHz hydroxyl maser in circumstellar envelopes has long been thought to be pumped by 34.6 µm photons. Only recently, the Infrared Space Observatory has made possible spectroscopic observations which enable the direct confirmation of this pumping mechanism in a few cases. To look for the presence of this pumping line, we have searched…
Detection of a classical δ Scuti star in the new eclipsing binary system HIP 7666
García-Melendo, E.; Gómez-Forrellad, J. M.; Lampens, P. +4 more
HIP 7666 is a variable star newly discovered during the Hipparcos mission and classified as of unknown type (ESA 1997, The Hipparcos and Tycho Catalogues, ESA SP-1200). During 23 nights between July 2000 and November 2000, over 2300 CCD observations in the V band were obtained. These data show that the new variable is a detached eclipsing binary s…
Mid-IR spectro-imaging observations with the ISOCAM CVF: Final reduction and archive
Blommaert, J. A. D. L.; Boulanger, F.; Abergel, A. +6 more
Mid-IR (5-17~µm) Spectro-Imaging observations towards several hundred sky positions were obtained with the Infrared Space Observatory Camera (ISOCAM), and a Circular Variable Filter (CVF) that provided spectral resolution R = λ/Δ λ ~ 45 over a 3' × 3' field (for 6, and 12´´ pixels, proportionally smaller for the observations carried with the…
Solar hydrogen-Lyman continuum observations with SOHO/SUMER
Vial, J. -C.; Parenti, S.; Lemaire, P.
In this work we analyze the emission of the H Lyman continuum (HI LyC) in the Quiet Sun (QS) and a solar prominence, in order to derive information on the temperature of the emitting plasma. We used the spectral atlas obtained with SOHO/SUMER detector A in 1999 (Parenti et al. 2005, A&A, 443, 679). The high spectral resolution of this instrume…
The influence of internal magnetic layers on the frequencies of solar p-modes
Foullon, C.; Roberts, B.
Buried magnetic fields at the base of the convection zone and in the anchoring zones of sunspots are presumed to vary over the solar activity cycle. Their effect on p-mode oscillations is explored in detail, through theoretical modelling. The helioseismic signature from a "tachocline" or "shallow" horizontal layer of magnetic field, buried in a pl…
Line broadening of EUV lines across the Solar limb: A spicule contribution?
Doyle, J. G.; Madjarska, M. S.; Xia, L. D. +1 more
Spectral lines formed in the solar transition region show an increase in the line width, peaking at ≈10 000 km above the limb. Looking at a region off-limb with no obvious spicules, the non-spicule region has a significantly smaller line width above 6000 km compared those taken in a spicule region. We suggest that this increase in line broadening …
Blinker/macro-spicule activity in an off-limb polar region
Doyle, J. G.; Banerjee, D.; O'Shea, E.
Using measurements of O V 629.73 Å from the Coronal Diagnostic Spectrometer (CDS) on board SOHO we report on blinker activity in off-limb regions above the Northern pole of the Sun. The blinkers are found to be occurring above a region showing strong dynamic activity, with evidence for evacuation of plasma. The presence of blinkers is discussed in…
<sl>Chandra</sl> and RXTE spectroscopy of the accreting msec pulsar IGR J00291+5934
Nowak, M. A.; Rodriguez, J.; Wilms, J. +4 more
We report on an observation of the recently discovered accreting millisecond X-ray pulsar IGR J00291+5934 performed with the RXTE-Proportional Counter Array (PCA) and <sl>Chandra</sl>-High Energy Transmission Grating Spectrometer (HETGS). The RXTE data are from a two-week follow-up of the source, while the <sl>Chandra</sl> …
Asymmetrical structure of ionization and kinematics in the Seyfert galaxy NGC 5033
Battaner, E.; Arribas, S.; García-Lorenzo, B. +5 more
We present integral field spectroscopy of NGC 5033, a low luminosity Seyfert galaxy. The observations were made with INTEGRAL, a fiber based system operating at the WHT. The intensity map of the Hβ emission line represents a spiral or ring-like pattern of HII regions. On the contrary, the [OIII] intensity map morphology is markedly anisotropic. Th…