Minutes from ISOLDE Physics Group meeting, 31st August 2016.

No comments to the minutes from the previous PG meeting:

Please read the minutes.

Technical news:

A Technical STOP on LINAC2 is planned for Wednesday/Thursday (in week 37) in order to exchange the degrading cathode.

Comments from the ISOLDE operators: USERS at ISOLDE should know the basic ISOLDE operations and at least one USER should have taken the ISOLDE Separator course. Especially when experiments are running at night.
Due to the problems with the HRS targets change, there was some re-scheduling of beam times this week. The collections on the GPS were cancelled and the Bi run was extended into the weekend as LOI168 are not yet ready.

HRS:
- Was on stand-by until Thursday.
- There were issues during target change Thursday/Friday.
  - Problems with unclamping the target
  - The installed old target (#573) showed a leak.
    - Another target (#562) was installed to exclude front-end leak. The front-end is in good shape, but more tests will be performed later this year.
- Target #574 has now been installed for Bi-run.
  - Pump-down and heating took longer than expected (outgassing), but the target is not leaking.

GPS:
- Has a reused lead target installed for Hg-beams #577. 3^rd time this year that this target has been used!
  - Delivered Hg-beams to mainly LA1 and only to GLM when LA1 was not taking beam.
- The beam setup was not easy, due to a double peak/wide peak from the target and ion source which is obviously not optimal
- Difficult beam tuning to LA1. A good beam could finally be delivered to the experiment on Friday afternoon.
- Beam tuning to the GLM was easier as the profile of the beam was less of an issue.
- Again during beam setup the extraction electrode moved into position 64 by itself.
  - The reason for this issue is still unknown and is being investigated. Maybe it is some default value in the software that overwrites.
- Problems with the tape station during beam setup – tape full error.
  - Gerrit Jan investigated and found that the PLC had stopped working. The PLC was replaced and tape station is up running again.
  - The new tape station should be taken into operation ASAP, since the old tape station is in bad/old condition.
- The line dropped to 0A on Saturday and both target and line on Sunday.
- For the second failure on Sunday, the main circuit breaker went off – maybe due to spark protection.
  - This is being investigated by experts.

RILIS:
- Has been setting up for Bi-beams.
- Bi is currently running on HRS
- Next they will switch to Sn isotopes for HIE-run.

REX/HIE:
- The control of the cryo-modules has become more stable.
- For the coming HIE-run the energy is at 5.35 MeV/u (the aim was 5.5 MeV/u).
  - They now concentrate on getting beam transmission and not a higher beam energy.
- A simpler interface panel for the superconducting cavities has been introduced.
  - It is still under discussion if USERS should have access to e.g. reset tripped cavities.
  - In any case USER training will be needed for experiments with HIE.

Targets:
- The production is going well and on track.
- LaC target for HIE-run is soon done and will be online on Friday.

LA1:
- The traveling setup, TATRA, was taking 189Hg and 183Hg-beams from GPS.
- They wanted to measure conversion electrons to complete the previous gama-gama study.
- Unfortunately when they finally had good beam transmission their tape broke two times. This could be fast repaired during beam time, and had to wait (2-3 h) for high vacuum.
  - However, they got good/enough data for proof of principle.
  - The run was to demonstrate that they could measure conversion electrons with a very high resolution and this was shown. They will come back to the INTC with an addendum.

GLM:
- Measured emission Mossbauer spectroscopy for biophysics using 197Hg decaying to 197Au.
- Got some collections done when LA1 was not taking beam.
  - Was difficult to collect enough activity in the ice.
  - A spectrum was obtained.
  - Was an overall ok beam-time that proved feasibility of the isotope and the setup.

Bi-run on HRS
- This week RILIS, ISOLTRAP, and COLLAPS want to further investigate a strange isomer state of Bi, that may have been observed during the windmill/ISOLTRAP run this year.

HIE
- Next week HIE-run is planned to start with 110- and 108Sn beams.
- Beams should be delivered before the 8^th (holiday Jeune genevois).

Target:
- The production of nano-targets has been reviewed and should improve the production procedure, but for the moment, production is still on hold (this will not affect beam time this year).
- The proton integrator on target (for GPS) was not turned ON.
  - This is important to know the target irradiation and for RP.
  - The number of protons being integrated should change with time – if not, please notify Operator.

Summer students:
- The summer students presentations were:
  - Kritsana Srakaew: Validation and testing of the collection chambers for the CERN-MEDICIS project.
  - Chris Gavanas: Summer Student Report, Script to automate tasks ASAP (After Set-Up Auto Save Application).

The next ISOLDE PG meeting will be held on 7 September 2016 followed by:

Summer student presentation from Christoffer Ricketts.
PG Seminar by Dan lascar "Recent TITAN Measurements and EMMATrap: An Introduction".

Minutes taken by ~TEM