ISAAC News

Instrument Status

SW detector state Several dust grains and flakes have appeared on the SW detector, two large ones are particularly annoying (see this image for details). To avoid them in spectroscopic observations, either set the NodThrow to values below 30 or above 60. You can also apply an offset along the slit to move the target out of the range of these features. An up--to--date description can be found on the QC problem page.
Grating reproducibility: We have problems with the reproducibility of the grating position. If the central wavelength is changed, offsets up to 20 pixels are observed. This can be a problem when more then one setup is used in an OB and the telluric standard is taken afterwards after the grating was moved. For the time being, we recommend that OBs contain not more than two setups, and if they contain two setups, clearly mark this in the README file. In those cases, we will try to take a telluric before with the first setup and one afterwards with the second setup, so that no shifts occur between the science target and the telluric.

P78: just a reminder: According to the Calibratio Plan the telluric standard will be observed just with the user instrument setup. The telluric will not be observed with the wide slit of 2''.
Call for Proposal for P79: The new modes Burst and FastJitter are now offered.