SA Input to TLT for 5-year Plan (Jan 2025)

@Marc Kassis @Carolyn Jordan

Sky Condition Monitors for the Telescopes (Josh)

The motivation is described in this white paper which was input for the strategic plan:

Rough budget details are included in CI #74 “Real Time Monitoring of Sky Conditions”.

Because this speaks directly to data quality, it would be beneficial for archive users. Thus, implementing this sooner means we will benefit a larger fraction of archival data as time goes on.

Building and testing new OSIRIS lenslet mask stage prototype (Sherry)

We propose to build and test a prototype of the new OSIRIS lenslet mask stage. We consulted Jim Thorne and documented the new design and hardware needs in CI #70. The goal is to have a new stage cryo tested and ready to deploy when the current lenslet mask stage fails again in the future. We propose to utilize test dewars at our partner institutes.

The current OSIRIS lenslet mask stage is prone to mechanical failures, and it requires an open-dewar service to fix the stage. OSIRIS calibrations are less stable with the frequent thermal cycles. The current design makes it difficult to align all the parts along the drive train, which is the main cause of frequent mechanical failures. The new design will be robust, reliable, and simple to maintain. The new design will greatly improve OSIRIS's longevity and stability in the years to come.

The deliverables are: a robust and reliable lenslet mask stage, built with off-the-shelf hardware, tested in a test dewar, and easy to maintain in the long term. AI&T and PDR will be documented. A rough budge estimate is in CI #76.

Instrument UPS for Basement/HISPEC

HISPEC is coming with substantial power needs and also the need for high uptime similar to KPF. We need to plan for UPS (and generator) backed power distribution in the basement to serve these two important instruments for the observatory’s future. KPF is looking at options for a dedicated UPS in the near future, but it is not clear if that is going to happen in time for the March install window. In either case, we should plan ahead for the HISPEC power needs and also handle KPF (unless we get the dedicated unit in for KPF beforehand).

The HISPEC needs are more substantial than we are used to for other instruments and they may also need glycol chillers to stay up as well. Here’s is some info from Jocelyn Ferrara:

The current power budget has the HISPEC bench & racks in the basement at 1.76 kW average and 2.9 kW peak – not including our two glycol cooled CCR compressors which combined have average 6.6 kW and peak 7.8 kW.

 So in sum, we have about 8.4 kW average and 10.7 kW peak for HISPEC basement equipment.

[...]

I assume you were made aware of the feedback in our recent SPEC review:

“Science return for PRV spectrographs is largely dependent on instrument up time and long-term stability, the review team is concerned that HISPEC’s science return will be significantly impacted by the power outages to critical systems which are not on instrument “clean” power at the observatory. Such systems include cryocooler compressors and glycol chillers. The review committee strongly recommends that the HISPEC team elevates this issue with observatory leadership and the SSC to strategize solutions that minimize instrument down time.”

We have explored some failure modes in the case that the compressors make it on to UPS and the basement glycol chillers do not, and there may be solutions in this scenario (but not in the case of compressors not on UPS and subject to every HELCO outage).

We should examine both traditional and lithium ion based battery backup solutions. Concerns have been expressed about batteries at high altitudes, but I suspect that is easily overcome. Here is an example news article about a high altitude solar + battery plant coming on line in Tibet at 17,000 ft.

Dome Flat Lamp Upgrades (Jim)

For MOSFIRE, the K1 dome flat lamps were upgraded to be brighter into K-band and to have more brightness adjustment. The K2 dome flat lamps are original.

Two step project: Update K2 dome flat system (lamps and projector) to match the K1 system. The immediate benefit of less time needed for dome flats. Simultaneously, study a new dome flat system that will cover the entire spectrum covered by our instrument suite with flexible brightnesses. Finally, implement the new system on both telescopes.

KCWI Blue Detector Controller Operational Programming Upgrade

KCWI’s blue detector has poor performance (increased noise and dark current) for several hours after the binning is changed. Additionally, while an exposure is in progress, exposure times may only be shortened, not increased. Both issues cause significant efficiency and performance drawbacks during KCWI split nights, when two programs with differing binning requirements must share the instrument or when we must respond to changing sky conditions. The entire goal of KCWI is to be configureable, but we are failing that goal in being able to switch between the blue detector binning modes (1x1 for the Small Slicer, 2x2 for the Medium and Large Slicers).

To be fixed, the operational programming/software of the blue detector controller must be adjusted. Based on Marc K’s estimates and UC Santa Cruz’s Statement of Work, this is about $250k for UCSC to do. We don’t have an estimate on how much money it would cost for WMKO to implement and characterize the changed software.