apo-wiki

Attending: Nancy Chanover (NMSU), Bill Ketzeback (APO), Joanne Hughes (Seattle U), Jamey Eriksen (APO), Ben Boizelle (BYU), Moire Prescott (NMSU), Eric Bellm (UW), Russet McMillan (APO), Chip Kobulnicky (UWy), Kevin Schlaufman (JHU), Adam Kowalski (CU), Sarah Tuttle (UW), Anne Verbiscer (UVa)

• Oklahoma - no report
• NAPG - no report
• JHU - nothing to report
• UVa - nothing to report
• Georgia State - nothing to report (by email)
• FGCU - no report
• NMSU - MP received a comment from a KOSMOS user re: the internal flat lamps; they are in favor of decreasing the lamp brightness to reduce saturation in the flats. Russet reported that we tried to make the lamps fainter but puzzlingly the flats got brighter in the red. We are still thinking about how to address this issue (see KOSMOS discussion below).
• Colorado - nothing to report
• BYU - nothing to report
• Wyoming - nothing to report
• Seattle - nothing to report
• Washington - nothing to report

Jamey's detailed report is included below, followed by additional information discussed during today's call.

3.5-m Telescope and Instruments Highlights, 3/01/2022 - 4/04/2022

0) Overview

APO is no longer under any staffing or indoor masking restrictions from the State of New Mexico due to COVID. The COVID daily cases are dropping in New Mexico currently.

Weather for March has been cold with multiple snow storms.

Q1 in person training wrapped up with CU during early March. Planning is underway for OU training upcoming in early April. The COVID vaccination policy for ARC/APO has not changed.

1) Telescope

The telescope experienced an (as yet) unexplained pointing shift in March. It appears to be related to an un-commanded movement in one of the secondary actuators. Pointing was reset and the telescope is being monitored.

2) Instruments

KOSMOS: Commissioning activities are continuing; the instrument is still being offered on a shared risk basis. A replacement shutter for the slitviewer is on order (low temperature operation issue).

DIS: Scattered light has leveled off for both the blue and red cameras. For the red camera the throughput is good for a stellar spectrum in the default position, but spectra of extended objects or targets off center on the slit may fall on contaminated areas of the detector. Throughput on the blue camera is about half of what it was earlier in 2021.

TripleSpec: Cold, operational and performing nominally.

Agile: Cold, operational and performing nominally. There is a known issue with missing observatory and WCS cards from the headers that we are trying to track down. This problem seemed to originate about the time we converted and moved the hub35m to a new server (mid December).

Echelle: Echelle inter-order light has leveled off.

NICFPS: The instrument is performing nominally with the occasional need to reset the controller due to corrupted images, and previous cautions about rotator angle.

ARCTIC: Cold, operational and performing nominally.

We expect to be working on the commissioning of two PI-level visiting instruments in Q2.

3) ARCSAT: Recent use has been relatively problem free.

We are still working to understand the unexplained motion of the secondary mirror, which has been happening occasionally (roughly once a month) since December. Now that we have traced this anomalous pointing change issue to motions of the secondary mirror, we have better plan to address it. Observers should tell their observing specialist if they see a noticeable change in pointing (> 15“). This issue is accompanied by a change in collimation but that may be harder to detect. When this issue occurs the observing specialist can do a correction; it takes about 15 minutes.

Sarah Tuttle is working on a test multislit mask for a user; this is a high priority. She is also working on getting a new set of slits made. As was previously reported, the slitviewer camera has a sticky shutter in cold weather. The replacement is on order but has a long lead time. We may be able to get by with the current camera until the fall since the weather is warming up. The new KOSMOS Users Guide (UG) is online; send comments/edits to Russet (https://www.apo.nmsu.edu/arc35m/Instruments/KOSMOS/userguide.html). We installed order blocking broad band filters per the instrument specs. Since this happened very recently this information has not yet been added to the UG; it is included here and will be added to the UG soon:

We are using the r2k and b2k prisms which means we would be using the following blocking filters GG-395, GG-455, OG-530 and OG-570. They can be used for the following instrument bandpasses:

• 3700-6200A None
• 3800-6600A None
• 4150-7050A GG-395
• 5000-8900A GG-455
• 5600-9400A OG-530
• 6150-9800A OG-570

These are loaded into the instrument, filter wheel 1. There is also a large format ND5 filter loaded in filter wheel 2 for very bright objects in spectral or imaging modes.

As mentioned above, we attempted to dim the internal lamps to avoid saturating the flats. We used a bulb with the same wattage as the old one but with a bluer color temperature, which was advertised to have half the lumens of the old bulb. However, we found that this new bulb was brighter in red. To mitigate this we added an ND2 filter at the output of the integrating sphere to reduce the brightness of all bulbs. We plan to add additional ND material to further cut the brightness; tentatively that work is scheduled to take place in ~ 1.5 weeks from now. Moire asked how people can get involved with tests of the multi-slit mask capability or whether requests for such masks are being handled on a case-by-case basis. Sarah replied that the slit mask generation software that came with the instrument is not working, so for now we are doing a simple test with an individual user but the goal is to make it more automated. The generation of slit masks is by its nature case-by-case since they are all designed for a specific and unique application, but if the software can be made to work then the entire process would require less lead time.

The first OPEN/DD time that is available in Q2 is at the end of April; we have already received some requests for it. There is quite a bit of OPEN time in June. The early OPEN time is in B half, whereas there are some A halves available in June. Interested users are encouraged to request any OPEN or DD time through the standard procedure, i.e. by emailing Ben, Russet, Nancy, and their institutional scheduler.

The Q2 ARCSAT schedule is ready to be posted. It is not fully populated so there will be open time that can be requested. Sarah asked whether the Shelyak is available for testing or shared risk use? Bill replied that it requires a lot more access to the computer systems than we have been allowing regular users, but he is open to training 1-2 more people in the current software configuration. In his estimation we are still a long way from being able to turn it over to students, especially if they are unsupervised.

The primary mirror realuminization is scheduled to take place the week of Aug 8-12, so a rough estimate of our summer shutdown dates is Aug 1-19. It may go farther into the following week. We are mainly sharing this information now so that users can plan ahead. There was a question of whether it pays to stay open in July given the weather, and instead perhaps we should try to get ahead on some engineering tasks. The response was that we should not extend the shutdown into much of July for the following reasons: a) Early in monsoon season the bad weather is earlier in the day, so B halves are often still useful. b) Although the chances of a totally clear (half) night are lower than other times of year, they are still better than zero, and we can also get instances of good seeing. c) There are limitations on how much we can get ahead on engineering tasks because several items on Bill's maintenance spreadsheet are still pretty very far away from the rotation of needing to be done this year (although Bill acknowledged that there may be a few smaller items that have been delayed or postponed that we do want to address). d) The last week of July is dark time, and we wouldn't want to give that up.

The 3.5m users wiki needed to be migrated to a different platform because the old one (trak) was not compatible with python 3. We identified a new wiki platform, DokuWiki, which we are migrating to. It should be straightforward to migrate users from the old wiki to the new one, and most of the old content was migrated from trak to DokuWiki.

Because we are in the midst of revamping the wiki, this is a good time to reevaluate its purpose, organization, content, and utility. A quick poll of the Users Committee reps indicated that most people either don't use it or have used it in the past as a reference for data reduction guidance. While it is not intended to supersede information that is on the APO web pages (maintained by APO staff), the user contributed wiki is viewed as a path towards documentation, i.e. a repository where users can report things that work, issues they have had with data reduction, etc.

The UC reps were asked to disseminate the link to the new wiki (http://astronomy.nmsu.edu/apo-wiki/) and ask users for feedback concerning the following:

• content: what is missing (what do you wish were there that you can't find)? are there obsolete items that can be removed?
• organization: does the structure make sense? is it easy to find what you are looking for?
• utility: how can we make the wiki more useful for user community?

The UC reps should plan to report the feedback they receive from their department members at our next meeting.

Open action items from previous meetings:

• Nancy: start investigations re: short wavelength throughput (climate data, other facilities). Status: OPEN. Nancy reached out to some colleagues at other observatories to ask about short wavelength performance degradation of their optical coatings. Still waiting to hear back. She will consult with Bill to make sure we are asking the right people.
• Nancy: coordinate with Candace on revisions to training feedback form
• Bill: add issue about debris in slits to KOSMOS section of instrument news web page. → CLOSED
• Joanne: provide Sarah with KOSMOS cals and also desired slit mask configuration. Status: she provided the links for people who want to take the cals from her observing account. She hasn't finished deciding what slit mask to use yet and will get in touch with Sarah when she is ready. → CLOSED
• UC reps: notify your users of remaining open/DD time in Q1 → CLOSED

New action items from this meeting:

• UC reps: notify your users of remaining open/DD time in Q2
• UC reps: get feedback from users on wiki (see above)

None.

The next meeting will be on Tuesday May 3, 10:30 am MDT. The remaining meeting date for Q1-Q2 2022 is June 7.