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86 GHz SiO maser survey of late-type stars in the inner Galaxy. II. Infrared photometry of the SiO target stars
Menten, K. M.; Omont, A.; Habing, H. J. +2 more
We present a compilation and study of DENIS, 2MASS, ISOGAL, MSX and IRAS 1-25 µm photometry for a sample of 441 late-type stars in the inner Galaxy, which we previously searched for 86 GHz SiO maser emission \citep{messineo02}. The comparison of the DENIS and 2MASS J and KS magnitudes shows that most of the SiO targets are indeed …
The configuration of simple short-duration solar microwave bursts
Nindos, A.; Kundu, M. R.; Grechnev, V. V.
Using data from the Nobeyama Radioheliograph (NoRH) we study the source configuration of four simple short-duration 17 and 34 GHz bursts which have also been observed partially by the Yohkoh Soft X-ray Telescope (SXT). Two events are consistent with a single flaring loop configuration. In one of them the flaring loop is resolved in the SXT images.…
A variable ultra-luminous X-ray source in the colliding galaxy NGC 7714
Motch, C.; Soria, R.
We studied the colliding galaxy NGC 7714 with two XMM-Newton observations, six months apart. The galaxy contains two bright X-ray sources: we show that they have different physical nature. The off-nuclear source is an accreting compact object, one of the brightest ultraluminous X-ray sources (ULXs) found to date. It showed spectral and luminosity …
HST observations of nuclear stellar disks
Jaffe, W.; Krajnović, D.
We present observations of four nearby early-type galaxies with previously known nuclear stellar disks using two instruments on-board the Hubble Space Telescope. We observed NGC 4128, NGC 4612, and NGC 5308 with the Wide Field Planetary Camera 2, and the same three galaxies, plus NGC 4570, with the Space Telescope Imaging Spectrograph. We have det…
Photometric estimates of stellar masses in high-redshift galaxies
Berta, S.; Fritz, J.; Franceschini, A. +2 more
We present a new tool for the photometric estimate of stellar masses in distant galaxies. The observed source spectral energy distributions are fitted by combining sets of various simple stellar populations, with different normalizations and different amounts of dust extinction, for a given (Salpeter) IMF. This treatment gives us the best flexibil…
Observations of the Pulsating White Dwarf G 185-32
Mazeh, T.; Hansen, C. J.; Kepler, S. O. +32 more
We observed the pulsating hydrogen atmosphere white dwarf G 185-32 with the Whole Earth Telescope in 1992. We report on a weighted Fourier transform of the data detecting 18 periodicities in its light curve. Using the Hubble Space Telescope Faint Object Spectrograph time resolved spectroscopy, and the wavelength dependence of the relative amplitud…
Subgiants as probes of galactic chemical evolution
Gustafsson, B.; Edvardsson, B.; Thorén, P.
Chemical abundances for 23 candidate subgiant stars have been derived with the aim at exploring their usefulness for studies of galactic chemical evolution. High-resolution spectra from ESO CAT-CES and NOT-SOFIN covered 16 different spectral regions in the visible part of the spectrum. Some 200 different atomic and molecular spectral lines have be…
A young and complex binary star - HD 144432
de Winter, D.; van den Ancker, M. E.; Bopp, B. W. +1 more
The southern emission-line star HD 144432 has received considerable attention due to its relative brightness (V ∼ 8.17), its late spectral type (late A-type or perhaps early F) and its relative isolation from a bona-fide active star formation region. We present new imaging and spectroscopic data of this star, which in the past has been classified …
A second glance at SN 2002ap and the M 74 field with XMM-Newton
Pian, E.; Soria, R.; Mazzali, P. A.
We have re-observed the field of M 74 in January 2003 with XMM-Newton, 11 months after the X-ray detection of SN 2002ap. From a comparison of the two XMM-Newton observations we obtain more accurate values for the X-ray luminosity and colours of the source five days after the event, and a limit on its decline rate. We compare its X-ray behaviour (p…
W Hya: Molecular inventory by ISO-SWS
Waters, L. B. F. M.; Feuchtgruber, H.; Justtanont, K. +2 more
Infrared spectroscopy is a powerful tool to probe the inventory of solid state and molecular species in circumstellar ejecta. Here we analyse the infrared spectrum of the Asymptotic Giant Branch star W Hya, obtained by the Short and Long Wavelength Spectrometers on board of the Infrared Satellite Observatory. These spectra show evidence for the pr…