Archive | Spectrograph | Data products

Series of observations

The instrument offers a mode where observations can be acquired in series. This is in particular used for asteroseismology, where long series of short exposures are commonly programmed.
The archive interface allows the user to either list all the observations, or to restrict the display to the first observation of series longer than four exposures. This choice can be set on the main query page.

Description of the series of observations

The following fields describe the series:

sseq
Sequence number of the series, defined as the sequence number of the first observation of the series.

slen
Effective length of the series. It can be smaller than nexp (scheduled length). This information is not available in the FITS headers.

nexp
Scheduled length of the series. Some observers schedule long series and interrupt them when their goal is reached, or when some incident (like bad weather) commands it.

expno
Index of a given observation in a series, starting from 1 for the first observation.