The Ohio State University College of Mathematical & Physical Sciences Department of Astronomy

Attendees: Darren DePoy, Ray Gonzalez, Tom O'Brien, Paul Byard, Jerry Mason, Mark Derwent, Dan Pappalardo, Pat Osmer, Bruce Atwood, Ed Teiga, Jason Eastman, & Rick Pogge.

Visitors:

Richard Green & Mark Wagner (LBTO) visiting OSU

Tod Boroson & Mark Trueblood (NOAO/TSIP) attending via videocon from Tuscon.

MODS Optics

Paul gave a status report on the fabrication and delivery of the remaining MODS large optics. We are awaiting 7 large optics from SOML: 4 correctors (2 each red and blue), and 3 camera primary mirrors. Thus far we have only received 1 large optic from SOML (the first of 4 camera primary mirrors).

At present, SOML gives the following tentative delivery dates for these optics:

• 2 Blue Corrector Lenses in March 2006
• 2 Red Corrector Lenses in August 2006
• Camera Primary #2: was to be shipped 2005 Oct 26, but is not yet done.
• Camera Primary #3: they are working on it, no completion schedule yet
• Camera Primary #4: no work yet.

The delivery of the MODS large optics from SOML is now beginning to drive the project schedule. SOML has missed all of the previous completion and shipping deadlines, and they have requested another extension on their contract. Pat will bring this matter up with Peter Strittmatter later this week when he visits Tucson. This continues to be a matter of increasing concern to the project.

Tom reported on working on various concepts for the MODS enclosure, and has generated an updated requirements document, which includes such details as the instrument cover design, the location of the mount points for the instrument electronics boxes (motor controllers, and associated electronics), CCD controllers boxes, cable pass-throughs, etc. The mounting points for the CCD controllers looks good, and a good location for the instrument electronics needs more refinement but converging. He will be moving to mroe detailed design work with a goal of producing fabrication plans and bid documents for the enclosure.

With the "Birdhouse" on west campus being readied for MODS2, this will give us a good space to work on the MODS enclosure parts in parallel with MODS1 work in the McPherson shop, as the aluminum enclosure parts are going to bulky and we have more room to work with them out on west campus before bringing them to McPherson for installation).

During the early testing phases, we will use a temporary fabric enclosure to make the inside of the instrument dust-free and relatively light tight (though we won't be as dark as the actual enclosure). Tom is reviewing material samples and possible vendors.

Current other work on the MODS mechanical systems is as follows:

1. Tom, Mark, and Ray are working out various mechanism interlock issues, specifically with regards to focal plane mechanisms (AGW stage and calibration tower) that could collide.
2. MODS2 structure will be arriving within the month of November, likely towards the end. All that remains is installing the collimator tubes and cleaning and painting. This is all within contract.
3. We have a PO out for the rigging company who will pickup the MODS2 structure from Indian Creek and deliver it to the Birdhouse on west campus.

IMCS Testing

Work proceeds. We are waiting on the completion of the "4-wide" motor controller box and associated software. Ray reports that the software is ready except for refinements using the actual 4-wide box, and Dan reports that the 4-wide box is about 90% done and will be handed off to Ray and Tom later this week for shake-down. The three Tip/Tilt/Focus (TTF) actuators are mounted on MODS1 and ready to go. An analogous set of TTF actuators will be used in the lab to shakedown the 4-wide box and software upstairs before moving into the lab.

Dan and Ed have wired up the elevation drive for the IMCS testsing, and tested it in the lab. It is ready to be re-installed on MODS1.

MODS Slit Masks

Tom is working with a vendor in Rochester on a 3-axis laser machine. We will be having them cut sample masks for us so we can assess slit quality and estimate the cutting parameters to better specify the laser and other machine specifications.

MODS CCD Systems

The MODS CCD dewars have been ordered, they should arrive in 16-18 weeks from receipt of the order (e.g., late March 2006).

Bruce reports that E2V requested a 4-week extension on their CCD detector fabrication proposal earlier in October. We are giving them until Nov 15 to respond with a bid. We will make our decision about the MODS custom CCDs after that date.

Bruce also reported on the results of his tests of new 18-bit A/D converter chips. He declared them "pretty fantastic", and only $42.48 each! He's running them in the tests at 1.75 microsec conversion rate, but there are other models that run nearly 4 times faster (2MHz) that he is going to check out. These should give us excellent sampling of the full dynamic range of the MODS first-light and custom CCDs.

MODS Electronics

Dan reports that the 4-axis motor control box (the "4-wide box") is about 90% complete and ready to be used for IMCS testing (see above). Ed has wired up 6 TTF Actuators, which were tested out OK by Dan. Three are mounted on MODS and 3 are in the lab. Ed also made 4 cables for the 4-wide box for use in the IMCS testing, and is making 6 copies of the wiring for the grating tilt actuators (2 sensors + 4 motor leads each).

The next issue is the exact size and connector plan for the Instrument Electronics (IE) box, and the creation of a full dummy mechanism with a complete suite of sensors and connectors. The latter is going to be useful for software and electronics testing, but isn't needed right away so is lower priority behind the IE layout issues.

MODS Software

Ray reported on progress on the Instrument Control System (ICS), which includes the MODS Manager package. Ray has hadded a quick command feature to the ICS that will make it easy to write simple command scripts for lab test and evaluation tasks.

MODS Schedule

Darren reported on revisions of the MODS schedule. The current internal schedule has MODS1 going to LBT in the first quarter of 2007. However, the LBT schedule, given secondary mirror and LUCIFER commissioning activities, has us moved forward to ship MODS1 in June/July 2007, and begin commissioning in September 2007.

This does not affect or internact activities as we have a lot to do in the next couple years. We'll review this in 4-6 months to see where we are vis-a-vis the evolving LBT construction schedule.

LBT Gregorian Rotator

An issue that has arisen is that the LBT straight-through Gregorian Rotator, where MODS mounts, is still unresolved, and there is no real schedule for its delivery. An engineer at Steward has been tasked with creating a detailed design, but has not completed this task to the level of fabrication drawings before being re-tasked with the bent Gregorian rotator work.

Needless to say, we are very concerned, as the Gregorian Rotator as a substantial lead time, and it's design is not yet complete, much less begin fabrication. We need to keep on top of this issue, and we took advantage of the presence of the new LBTO directory Richard Green at our meeting to make our concerns known.

SPIE Meeting

The next SPIE Astronomical Instrumentation Meeting will be in May 2006 in Orlando, Florida. The abstract deadline is Nov 7. Currently there look to be 5 talks/posters from Team MODS:

1. General MODS Overview Poster (Pogge et everyone)
2. MODS Slit Mask Materials Poster (Tom et al.)
3. IMCS System (Jennifer et al.)
4. MODS Instrument Control System Software (Ray et al.)
5. LBT Aluminizing (Bruce, Dan, et al.)