by Joe Liske on 2022-03-31
4MOST is built around three spectrographs that will collect the spectra of up to 2436 astronomical objects simultaneously. Two of these are identical low-resolution spectrographs (LRS), one is a high-resolution spectrograph (HRS), each fed by 812 fibres. Each spectrograph has a blue, green and red arm, in fixed configuration, and each arm is equipped with a 6k × 6k CCD detector. The two LRS provide continuous wavelength coverage from 390 to 950 nm at a resolution of R > 4000. Once completed, all three spectrographs will be sent to the AIP for system testing and validation.
In December 2021, integration of the first of the three spectrographs (LRS-A) was completed at the 4MOST consortium institute CRAL in Lyon. After acceptance testing, it was disassembled and packed in preparation of shipment to the AIP. On 29 March 2022 the disassembled LRS-A arrived at the AIP on four trucks. A team of five colleagues from CRAL, supported by the 4MOST AIP integration team and two colleagues from MPIA Heidelberg will spend the better part of the three following weeks to unpack and reassemble the spectrograph.
The delivery of LRS-A is a major milestone for the 4MOST project and we are very excited to receive it and follow its re-integration in the integration hall. The two remaining spectrographs are scheduled for delivery to the AIP in August and October of 2022.
See also this AIP press release.