H* weekly meeting

Monday 21 Feb 2022, 16:00 → 18:00 Europe/Zurich

Present: Fredrik, Maxime, Tim, Chloé

1) New indico page and zoom room  for H* activities
Please upload slides and minutes so that we can keep track of discussions

2) - TRIUMF team account is setup: T276020
Can start making purchases. 

3) status of THz deexcitation setup

- Daniel sent the lamp last week but igniter missing. Custom made costs a lot. 
Can we make it ourselves?  Check what is required upon arrival

For info
Globar equivalent temp: 1000C
Mercury lamp: 5000K

- Tests with Globar lamp
Maxime: changed plasma parameters but is limited in flow (pressure in cavity) because of pressure issue in the 1st chamber. Indications that higher cavity pressure lead to higher amount of high Rydberg states. 
This is due to problem with the pump 
-> proposed solution: make smaller pinhole:
This is a priority for this week to be able to make new measurements with the Globar lamp.

3) status of circular state excitation

- Helmholz coils are here. Adjustment of the height of the setup needed. Beware of the laser path 
- Switching pulse to the electrodes: need 50V DC power supply -> use the 2nd MCP power supply
- Fredrik: check the numbers for 2S quenching. 

- Chloé send contact of central workshop

- status of electron gun test (was not discussed)

- triggering signal does not work -> check with epool
 

4) List of ORDERS
-) Teflon o-ring between tube and first chamber 
-) THz Sensor 
-) Aluminium blind flange, non-magnetic clamps 
-) KF feedthroughs -> ask quote or check if there are any at the CERN store

Laser room:
-> Stephane on holidays until March 10th. Chloé will setup a safety visit as soon as he comes back.
In point to be addressed is the googles (can we use the pump google only)

5) Preparation of discussion with JF Lampin
-) filters 
-) THz detector
-) distribution of frequencies : continuum versus discrete (circular only?) : Tim is running some calculations
-) test with femto-laser to extract power versus frequency plot 

-> Fredrik and Tim to prepare a few slides for the meeting