Attending: Nancy Chanover (NMSU), Aleksandr Mosenkov (BYU), Russet McMillan (APO), Anne Verbiscer (UVa), Adam Kowalski (CU), Misty Bentz (GSU), Ben Williams (UW), Moire Prescott (NMSU), Joanne Hughes (Seattle U), Chip Kobulnicky (UWy), Michael Hayden (OU), Eric Bellm (UW), Sarah Tuttle (UW), Bill Ketzeback (APO), Gordon MacDonald (APO)
The detailed site report is included below, followed by additional information discussed during today's meeting.
3.5-m Telescope and Instruments Highlights, 9/03/25 – 10/07/25
1) Overview
Monsoonal patterns continued for much of September, with unsettled weather affecting all but a small handful of nights this month. There were no visiting classes or PI instruments staying on site during the month. However, we did host daytime tours and had remote training sessions this past month. The 3.5m Night Operations team saw the departure of both Candace Gray and Mark Croom. We wish them both in their future adventures!
The site will be holding an open house event for the public (daytime only) on October 11. Science demonstrations, public talks, and tours of the telescopes will be the highlights of the four-hour event.
2) Operations
3.5m Telescope: Telescope is working as expected. Seasonal motion errors continue to occur infrequently. We anticipate that there will need to be some tuning of the axis drives by mid-November. This past Saturday, there was an occurrence where one of the three axial actuators for the secondary mirror did not move after an instrument/ port change. The operator corrected the problem by homing the secondary. The weather at the time was poor, so no time was lost.
0.5m Telescope: Telescope is working as expected. Dcam-spare and UVAcam are both available options for users.
KOSMOS: System is cold and stable. Increased dark current for long exposures has been confirmed. As discussed last month, the increase in dark current warranted opening the cryostat for inspection. Three of the four thermal connections from the liquid nitrogen can to the CCD cold block had failed, leaving only a single thin connection. Repairs were delayed by the shipping of material from Europe. We are currently searching for a vendor to assemble the parts, as we have not had success ourselves.
ARCTIC: The diffuser rotation mechanism is still unreliable even after a full servicing. The mechanism that moves the diffuser in and out of the optical path is still functional in the meantime. The rest of the instrument is cooled.
Agile: The camera is non-operational; the thermoelectric cooler failed again. The camera is warm, and we do not plan further repair work with this camera. We are planning on decommissioning the camera. The agile instrument rotator is still not performing nominally, and we are troubleshooting it further to prepare for SoonerCam.
ARCES: While working on automating the interorder light reductions and archiving the data in a new database, we discovered that the FITS header KEYWORD for DATE-OBS was wrong by approximately 45 minutes in the future of when an image was written. Further data mining revealed this occurred during the summer/fall of 2024 when the ICC experienced power supply failure and hard drive troubles. It was not caught that the operating system service that syncs time to the site timeserver was not performing. The problem would have started on or after August 27, 2024. If time stamps are important for your echelle observations users should take note. A report from a user that the new ThAr bulb, replaced on July 22nd, had very weak lines or missing lines in the mid and blue orders prompted us to replace the bulb again on September 29. Wednesday, September 30th, observers then reported that the ThAr counts were around 3250 DN last year, but only 3100 DN counts tonight. This was the last new HCL we had on the shelf. It may be these two bulbs had lower pressure argon gas fill and therefore those are the lines missing. Comparison with line lists would need to be done to confirm. More bulbs are on order; however, Thorium-Argon lamps of the same type and manufacture as we were purchasing years ago are no longer available. We are buying up one European vendors back stock but we do not know if these will be of the same lamp strength as the old bulbs.
DIS: System is powered down and warm. Decommissioning plans have begun.
NICFPS: System is cooled and usable.
TripleSpec: System is cooled and usable.
APOLLO: The instrument is usable for laser ranging.
Highlight some of the items - APO hosting Open House this coming weekend. Giving public demos, tours, talks over 4 hour event. 3.5m telescope is performing as expected for this time of year; had a significant failure one of actuators on secondary froze when changing between 2 ports. Homing of mirror correct problem with no further issues; caught during poor weather so science no time lost. 0.5m working as expected; Dcam spare and Uvacam are available to users for Q4. KOSMOS. Report incorrectly stats that cold and stable; it is not it is warm and in parts. Increased dark current reported by users; last month concluded that becoming unusable for science. Didn't want to wait for December to do inspection, Upon taking it down, 4 thermal connections between LN2 cold strapping and cold block that cools CCD; 3 of them were broken; only 1 was providing cooling. Ordered new strapping material to do a repair. Delayed because had to come from Europe. Once arrived we did not have correct knowledge to repair; much more difficult than what we can do on site. Reached out to vendors, got quotes, cold head block and various pieces sent out to shop in Albq. Need to procure materials. Hoping by early next week the repairs will be completed and picked up, then vacuum cleaning baking out, preparing dewar for service. Hoping for end of next week for return to service.
Nothing new on ARCTIC. Echelle - working on steamlining reaction software for calculating IOL; discovered that DATE-OBS keyword was wrong (45 min in the future from when image was written) - then did some data mining; this occurred in late August 2024 but not caught until now. If time steps are important for your echelle observations - ARCES observers should take note and we can provide the detailed time offset for anyone for whom this is critical. Report by a user a few weeks ago that new Th Ar bulb replaced in July 2025 had some weak/missing Ar lines in blue orders. We replaced with a different spare - did this on Sep 29. On Sep 30 reports that the new bulb was slightly fainter than bulb a year ago. Reduction process is more efficient now. Users should also note this. Hollow cathode lamps - can no longer obtain Th metal filaments; increasingly hard to find on the shelf. We just purchased some supply so that we have spares - hope that each one will last a few years each. Becoming harder to find old style THAr lamps. Alternative source may need to be identified.
Agile/DIS decommissioning.
NICFPS and Tspec working nominally as is APOLLO.
The Q4 schedule is posted. Fair amount of OPEN/DD01 time in late October (dark). All B halves. Hoping to use it to pay back some of the KOSMOS users but not committing until know when KOSMOS returning. Some of KOSMOS time may need to be allocated to other users. Ideally from same institution. Additional OPEN/DD01 time later in quarter, including limited number of A halves or partial A halves. Thank you Russet for doing such a good job with the challenges for this quarter.
The ARCSAT Q4 schedule is posted. Pretty full, but this week is open (rest of this week). Some other time available later in the quarter. Two instruments are UVa-cam (larger FOV), Dcam-spare, smaller FOV and less oversampled but Dcam-spare did have some frost after shutdown; gone now but see signatures on detector; they flat field out but looks ugly when takking data.
There are a number of events taking place over the next several months:
Open action items from previous meetings:
New action items from this meeting:
Timeline for KOSMOS? Jan. chip temp increase. Late winder/early spring prob not affected. Mark Croom
The next meeting is currently scheduled for Tuesday November 4, 2025. This directly conflicts with the ARC Board meeting; shall we reschedule for one week later or cancel the November meeting and meet again in December?
Gordon - working on new release for TUI - v3.2 - plans to get it out soon. Had some instruments decommissioned, cleaned out old scripts. Most exciting aspect is working on packaging to make install process more simple for users, especially students. Get the changes automated to be download to Git Hub. Prev versions will still work but encourage uses to keep updated.