Minutes from the ISOLDE Physics Group meeting on November 27^th, 2014

No comments to the minutes from the meetings on November 20^th.

Technical news

GPS

• GPS was run at 30 kV past week. The new UCx nano-structure target holds 50 kV. HV problems to be investigated.
  
  • Extraction electrodes are changed during the winter shutdown every year.
  • A new design including the electrodes connected to the target body is being developed.
• Faraday cup FC490 is confirmed to read 2x more than FC5580. To be looked into during the winter shutdown.
• New UC_X nano-structure target installed.
  
  •  Yield tests on the weekend (update Monday: Isolde tape station broke Saturday afternoon, beam to CRIS and then IDS).
  • IDS IS579 ^150-152Cs beta-decay after the weekend.
  • VITO stable beam and collections after IDS.
• New PSB settings to GPS target after retune of proton orbits. They can reach 3.3 10¹³ protons per pulse.
• New controllers for the magnet should be ready for next year.  
• The new power supply for the magnet should be delivered mid next year.
•  

HRS   

• Standard UC_X  target from CRIS campaign still in place.
  
  • Extraction voltage increased from 30 to 40 kV for CRIS.
• ISCOOL set to continuous mode with bunch mode settings. Users observe 20% transmission for ²³⁸U. Under investigation.
• Some issues observed after software update. Fixed.
• HRS still using old PSB settings until a new proton scan is done for a new target for COLLAPS.
• The vacuum control software was updated on Wednesday.
  
  • VITO pressure gauge controller currently closes the CRIS valve. Switched off for now. Under investigation by vacuum group.

RILIS

• The replacement pump lasers for the TiSa lasers were delivered 2 weeks ago: one installed and used for the CRIS run; the other one still being internally delivered by CERN.
• A new pump laser of the offline lamp will be delivered shortly.
• New filters required for flammable gases and laser dyes for the air exhaust will be replaced during the winter shutdown.

REX

• Next week radioactive beam will be taken to REXtrap and EBIS

Schedule

• CERN wide power cut scheduled for December 16 6:00 to 7:00 am.
• Schedule after December 13^th.
  
  • Collection of long lived Holmium at GPS; PSB protons will be stopped on Monday December 15 at 6 am.
  • HRS stable beam tuning with the automatic tuning software; Continue with stable beam tuning on Wednesday after the power cut.
  • Targets removed on Thursday; cooling water in the hall stopped; power supplies for the beam steering turned down.
• Cooling water will be back as usual on February 27^th.
• ISOLDE separator course for users should be held last week of March.
• ISOLDE will be ready for first protons on the 9^th of April.

Safety

• Fire alarms set off in the HIE-ISOLDE building; they were triggered when connected and by dust.
• Siren tests scheduled for the HIE-ISOLDE building for Friday 5 pm.
• There were measurements of radioactivity in the air released from the balloons. A spike was observed at the beginning of November.
• One of the target UC_X  ­pellets caught fire during transport. The incident report indicated that the proper procedures were followed.
• Users indicate that the plastic tubes of roughing pumps are left open in the hall. This could be dangerous because of radioactive gases released from UC_X targets.
• The coordinator indicates there are no users signed for the RP course on December 9^th;
• Please use the hand & foot monitor every time when exiting the hall.
• LN2 accident at the IDS; safety inspection suggests to have CERN cryogenics check the clovers’ release valves.
• The dewars stored at B275 need to be checked for conformity with CERN regulations 

CRIS

• Goal: measure the ground state properties of neutron deficient Francium isotopes.
• First experiment using the CRIS high resolution lasers; for ²⁰³Fr they used low resolution again to increase the efficiency.

Solid state

• Run for ²⁷Mg 48 hours without incidents;  30% transmission with 1 mm collimator
• Goal: study Mg properties as a dopant in GaN semiconductors applied in blue LEDs; the technique uses the beta decay electrons and gammas to study the lattice site location of Mg with sub-Angstrom high-resolution.

VITO

• Alignment finished and ready to take beam next week.
  
  • The alignment for the entire beam steering parts line was done first for the internal part of the elements electrodes then for the external case of the element.
  • The line was aligned with respect of the central beam line switchyard. It’s not corrected for the 8.7 mm change in height of the central beam line.

B508

• Elisa Rapisarda found furniture for B508 at CERN recuperation. Seven aluminum cupboards, 8 big and 2 small plastic tables, 4 chairs (no wheels), one blackboard, one whiteboard, 2 wooden tables, 2 wooden chest drawers.

AOB

The next meeting will take place at 15:00 Wednesday next week   (3^th December 2014) followed by a seminar by Stephan Malbrunot (https://indico.cern.ch/event/354406/)

Minutes taken by MMF