Minutes from the ISOLDE Physics Group meeting on July 15^th, 2015

No comments to the minutes of the PG meeting held last week.

Technical news

• GPS:
  
  • Thorium Oxide target with negative ions source installed last week.
  • Very small yields observed, no Po or At. Currently, one possibility is  the ion source electron deflector which was found disconnected from the power supply. the deflector was also disconnected for the previous negative-ion target.
  • After the electron deflector was fixed yields on stable I (from mass marker) increased by a factor of 50. To be seen if the same effect is observed for radioactive ions.
  • Next GPS target (UC_X with Rh surface ionization for Potassium decay) will be installed Monday.
• HRS:
  
  • Version 2 of the HRS power supply software has been installed avoid the problems observed in Version 3.
  • The HRS fellow finished a new version of the HRS magnet cycling capable of changing masses in 2 minutes.
    • Preliminary tests show the beam does not always come back to the same position. Thus, the old version will still be used.
  • The last HRS target was not clamped properly making it impossible to pump. Traced back to the same clamping piston problem that developed last year (this time the rubber joint disintegrated). Problem fixed after parts exchanged.
• Beam diagnostics:
  
  • The new diagnostics box in front of ISCOOL was successfully pumped. The faraday cup still needs to be cheked with beam.
  • The CA0 faraday cup was successfully substituted and leak tested.
  • The IDS and ISOLTRAP faraday cups will be repaired and tested soon.
• ISCOOL:
  
  • Transmission tests will be made now that vacuum conditions have improved after the diagnistics box repair.
• The ISOLDE He leak tester is still being repaired. Vacuum group will let the group borrow one meanwhile.

Safety

• The coordinator reminds people the kitchen should be used exclusively as a kitchen and not for repair or electrical work.
• Users now should register to the  hands-on electrical and radioprotecton courses at least one week in advance. The budget code provided must be from one of involved team accounts at ISOLDE, not the ISOLDE team code.

Schedule          

• The coordinator will be away from Friday 17^th to Sunday next week. Please contact Miguel Madurga in urgent cases.

Test of target-ion source for negative ions

• Goals: Th target with surface negative ion source
  
  • Aim: Measure for the first time electron affinity of Astatine. From it the electronegativity and chemical properties will be deduced.

ISOLTRAP

• Goals: Neutron rich Ar isotopes across N=28 shell closure
  
  • Erosion of the N=28 magic number in the Ar region.
  • Complete mass measurements in the N=28 region.

AOB

-Users suggest adding a signpost at B508 staircase for transport services to  deliver packages.

-Users point out the ISOLDE vacuum cleaner is full. The old bag needs to be disposed by RP and a new one will be installed by Julian.

-The next meeting will take place at 14:00 Wednesday next week (22^nd April 2015) followed by a seminar to be announced.

Minutes taken by MMF