Our paper Benchmarking the design of the cryogenics system for the underground argon in DarkSide-20k is on the arXiv today: http://arxiv.org/abs/2408.14071. The paper discusses the current design status of the system in view of the DarkSide-20k requirements, shows the benchmarking and testing efforts of its integral system components in a dedicated testing platform at CERN and LNGS, outlines implications of the results for the final system design and provides an outlook to ongoing activities. I am very proud that I was part of the team who pushed this project through, leading the benchmarking at LNGS and the paper writing. Congratulations to the entire team involved and thanks to those colleagues who spent their time reviewing the manuscript internally or who were involved in the editorial process.
This week I am participating in the 15th International Workshop on the Identification of Dark Matter at L’Aquila! I am thrilled to present the Underground Argon Cryogenics System of DarkSide-20k at this important conference. My poster contains the main results of a paper on that topic which is currently under Collaboration-internal review. Looking forward to this exciting event!
DarkSide Summer Collaboration Meeting
The Summer collaboration meeting took place at LNGS from 10–14 June. I presented two topics: Simulations on the distribution of internal calibration sources in the active volume and the results from the mockup cryogenics test at LNGS.
Multi-Tube Heat Exchanger Installation
This week DarkSide had a meeting with the INFN Review Committee with fruitful discussions and good feedback. I presented the results of the first run of the UAr testbed for the DS-20k detector Mock-up in the UAr Cryogenics breakout session. We used our spare time to open the cryostat and to install the new heat exchanger geometry. After performing a couple of other upgrades and maintenance on the setup, we are on track to restart operations beginning of February!
Liquid Argon Run
Liquid argon is running through the veins of our UAr cryogenics test stand! The cryostat is fully filled and we commence the testing of the cooling control system and the system efficiency.
First Parts for the Mockup TPC
For the DS-20k Mockup TPC I am responsible for the design of the capacitive short level meters, the liquid level control and a cryogenic camera. The first parts are already finished. Thanks to the team of the Mechanical Workshop of the Physics Department of the University of Zurich for the incredible machining job! In the pictures we see the bubbler/boiler unit and parts of the level meters for the liquid level control.
DarkSide General Fall Meeting
This week we had a Collaboration Meeting at GSSI in L’Aquila, Italy. I presented the progress on the cryogenics test within the Mockup programme and gave an update on the UAr Working Group activities.
Start of the Run
The run has started today and we are currently acquiring valuable data with gas argon at room temperature to characterise the compressor performance and the flow resistance of the recirculation circuit. Thanks to everybody involved – the reassembly of the system at LNGS after the transport from CERN was a huge amount of work and the start of the run is an important landmark.
Phase Separator Installation
This week we have installed the nitrogen phase separator on the cryogenics system test bed in Hall C at LNGS. This is the last major piece of the setup. The run can start soon!
In the week of 12–16 June, the collaboration came together for a general meeting and progress review at LNGS. I had the opportunity to present the measurement prospects with the Mockup detector which will soon start operations, and I could engage in fruitful discussions on cryogenics-related aspects. It was also inspiring to see the exciting progress on the installation of the warm structure of the cryostat underground.