Building

To improve the temperature stability an extra heater was installed in front room to minimize the temperature gradient between the spectrograph room and the front room. To get a better temperature control a total of 12 temperature sensors (with 0.01 degree accuracy/precision) were placed in and around the spectrograph. These are necessary to relate any Echellogram shift to physical phenomena on the spectrograph table, and for further improving the temperature stability. Unfortunately all these new units were damaged in the lightning storm and will have to be replaced. The measurements from these sensors will also be integrated in our data base and a graphical interface will be provided.

From the measurements during last summer it is clear that on the hottest days, which typically coinciding with days with `calima' (Sahara dust), the temperature in the building is affected and some solution should be found before the coming summer. This likely will mean painting things white and/or adding small (white) peddles to the roof and the area in front of the main door where the ventilation is located. There might also be a need for forced cooling using an air-condition either in the front room or above the false ceiling.

To analyze the temperature stability of the spectrograph a automated analysis tool will be developed.