The authors present an improved iterative method for deriving temperature corrections in stellar atmospheres. At each step of iteration, the procedure computes, from the current values of the radiation field, a set of depth-dependent factors, averaged over angles and frequencies. Even a crude initial estimate of the radiation field leads to a

Observations of 176 stars have been obtained by filter photometry over the 1-4 micron range at the Observatorio del Teide in Tenerife. Measurements for Jn, Kn, and Ln relative to Vega are presented, along with the probable errors of those stars observed for several nights during two of the three observing sessions. Mean quoted probable errors of 0

Two broad components in the strongest UV emission lines of NGC 5548 are identified. The components respond differently to continuum changes. A normal broad (5000 km/sec) line is related to the UV flux, but the data-set only provides an upper limit for the possible lag. The very broad (10000 km/sec) line does not appear to be affected by continuum

Simultaneous UV and optical variations of NGC 5548 suggest a common origin of the continuum flux at both ranges. If the bulk of the UV flux had a black body like shape, its optical contribution would be too low to account for the observed variations, and a connection between UV and FIR changes would be needed, which is not observed. However, a flat

The temporal and spatial behaviour of the K I 769.9 nm solar line are investigated using several series of high spectral resolution low-noise photoelectric scans obtained at Kitt Peak National Observatory in quiet and active (plages and sunspots) regions. Corrections due to the instrumental profile were applied to yield the best line shape. A

IAUC 4613 available at Central Bureau for Astronomical Telegrams. IAUC 4613 available at Central Bureau for Astronomical Telegrams.