MOIRCS

The Update for S12B Applicants

2012-02-08 (update Feb 09)

Because of the telescope cooling system incident, the Cassegrain Auto Guider (AG) system will be unavailable for the remainder of S12A and the early period (at least during August) of S12B semester.

Consequently, the observations that rely heavily on the availability of the AG system could be severely compromised. For the spectroscopy (both MOS and longslit) mode, the accuracy of target acquisition on the slits could be quite poor without the AG system. The targets could go away from the slits quite easily for the exposures longer than 3 minutes. Thus the frequent re-alignment is necessary, which will result in the significant loss of observing effeciency (below 50%). As for imaging mode, the background-noise-limited performance may be difficult to achieve for observations with filters such as NB119, Y, etc., as we have to limit the maximum exposure to less than 3 minutes in order to keep the good image quality under the non-AG condition.

The applicants who intend to use MOIRCS during the early period of S12B should prepare some back-up observing strategy for the case the AG is unavailable. We apologize for the inconvenience.

When you apply for the MOS observation, you must explicitly write the required numbers of the MOS mask (both for the Full and the Minimum Number of Nights) in the Sect 11 of the application form. And also, please explicitly justify why you need the requested number of MOS mask on the technical detail part in Sect 14. Please note that the maximum number of MOS mask available for one contiguous observing period is 15.

Please note that the number of MOS mask will be fixed once it is assigned by TAC's critical reviewing. The request for any backup mask is basically not permitted, unless there are any special reasons.