Berkeley workshop summary Redundancy : dual detector Field of view : 3”x6” Spectrograph length goal: < 400 mm Isostatic mount on the base plate with control of the focus Spectrograph shielding analysis by LBL Spectrograph weight 15 Kg CCD: reduce pixel size due to radiation rate 9x9 µm 2 / 100 µm thickness check feasibility by LBL HgCdTe: first test bench with 1.7 µm if 100k$. Best for spectrogrqph is 1.9µm cut off. Check operating temperature

Berkeley workshop summary Temperature IR sensor at 100 K reasonably possible and 70 K difficult Calibration : use imager lamp for flat fielding and wavelength calibration, put lines using gas lamp or Fabry-Perot internal calibration bench only for cross checking with ground calibration Remove spectrograph shutter /use imager one for stars, and back illumined for lamp Common calibration mode with imager Observation scenarios should be defined SNAP request : hardware control is a spectro charge, software integrated in the common OCU. Data acquisition : data go in a common memory system, compression taking in charge by the memory system.

Next visit March status on the CCD thin development status on IR detector status on bench test status of interfaces structural model performance report Scheduling of visits: Collaboration meeting Spectro status july or september

What happens next New spectrometer package Shorter Dual ccd Dual mct Shielding New mount footprint Details New cal light test array New interfaces Robin summary