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I$_{2}$ Cell and Light Monitor

Observations involving the iodine cell require additional calibration frame. It is an exposition of the halogen (flatfielding) lamp taken with the I cell in the optical path. This exposition should be done with the same settings (slit, echelle format, etc.) ast the science spectra. Alternatively, such a calibration can be done during the night by observing a bright, early-type, rapidly rotating star, such that there are no sharp features in the stellar spectrum, only rotationally broadened hydrogen and helium lines.

At present, control of the I cell and light monitor is possible only with the instrument control computer (OBCP).



next up previous contents
Next: Characteristics of the Data Up: Observing Previous: Calibration Data   Contents

aoki, helminiak, tajitsu 2014-02-11