Summary of meeting at the ARI, Liverpool John Moores University on 15/03/2000

Attendees

• Vik Dhillon.
• ARI: Dave Carter (LT Project Scientist).
• ARI: Iain Steele (LT Assistant Project Scientist).
• TTL: Paul Rees (LT Project Manager).

I asked a whole series of questions regarding the Liverpool Telescope (LT) optics, its mechanical and electrical interfaces, and various operational issues, to which Dave Carter and Iain Steele responded to during a meeting at the ARI, and to which Paul Rees responded to during a tour of the TTL factory.

Optics

• Can we have detailed description of the optical layout of the LT for Tully Peacocke? Yes, but DC suggested that he could get them directly from Sue Worswick at the UKATC.
• How far is the focal plane of the LT from the A&G box mounting plate? 75mm, but it can be moved approximately 50cm either way by moving the secondary mirror (which also introduces spherical aberration).
• What is the field of view at the A&G box? 7.5 arcminutes (zero vignetting) at the side port and 42 arcminutes (zero vignetting) at the upward-facing port.

Mechanical/Electrical

• Can the Cassegrain cluster rotate? Yes.
• What are the mechanical interface requirements? Identical to the WHT A&G box - Paul Rees can provide us with technical drawings.
• What is the space envelope? Paul Rees provided me with a data sheet. The side port is too small to mount ULTRACAM. The upward-facing port might only just be able to accommodate it.
• What is the mass limit? Also on the data sheet. There is no problem mounting an instrument of ULTRACAM's mass on either port.
• Where can the electronics racks be mounted? On adjacent ports on the A&G box, which have been designed specifically for this purpose.
• Where can the computers be placed? In the control room, using the cables provided on the A&G box. They would prefer us to use only a single monitor in the control room due to space restrictions.
• Can we use a water/glycol chiller? Yes, as long as the vibration is negligible if mounted on the A&G box. (They would prefer not to have cables dangling to a chiller on the floor).
• How is the LT PCI development coming along? Quite well - Bob Leach has taken images in the lab with their soon-to-be-delivered CCD camera.
• Is there a dry-nitrogen source at the telescope? No, but there is a dry-air source, which is just as good.

Operations

• To get time, should we go through the normal PATT application process? Yes.
• How frequently might we be allowed to use the instrument on the LT and for what lengths of time? It would probably work as follows: We would submit an application to use ULTRACAM on the LT to PATT. We would also invite others to submit applications in collaboration. If a certain minimum number of hours is awarded to make it worthwhile, ULTRACAM would be mounted on the LT once in the semester for as long as it takes to complete the scientific programme. ULTRACAM would be mounted at the upward-facing port, so the LT CCD camera would have to be moved to a side port (with a consequent loss in the maximum number of filters available). This would require a LT staff member to accompany us on the trip, which should be funded from our PATT application.
• Can we get any commissioning time? We should ask PATT for this as part of our first application for time on the LT.
• Is there anything else we need to think about? Yes, do we need a GPS aerial? LT has one, but we should make sure it is compatible with our GPS card.

vsd, 03-apr-2000