We present deep imaging at 6.7 and 15 mu from the CAM instrument on the Infrared Space Observatory (ISO), centred on the Hubble Deep Field (HDF). These are the deepest integrations published to date at these wavelengths in any region of sky. We discuss the observational strategy and the data reduction. The observed source density appears to

A new iterative method for solving non-LTE multilevel radiative transfer (RT) problems in 1D, 2D or 3D geometries is presented. The scheme obtains the self-consistent solution of the kinetic and RT equations at the cost of only a few (

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Cyg OB2 No. 5 (BD+40deg4220; V729 Cyg) is known to be a contact binary system formed by two O-type stars. For this object a 6-cm radio emission has been detected at the optical position as well as an additional weak non-thermal radio source located at ~ 0.9 arcsec to the north east of the contact binary. It has been suggested that this radio

IAUC 6721 available at Central Bureau for Astronomical Telegrams.

A new method of fitting tridimensional power spectra of solar oscillations is described and compared with a previous one whose use has been more common. The new method fits the parameters of the Lorentzian profiles in a bidimensional k - omega diagram constructed from an azimuthal average of the tridimensional one. The horizontal velocities are