Task 11.2: Fragmentation of post

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Task 11.2 Fragmentation of post accelerated ISOL
beams
David Pérez Loureiro Universidad de Santiago de
Compostela, Spain
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Production of extremely neutron-rich nucleus

• Two step scheme fission cold fragmentation

n,p 238U ? 132Sn Be ? X

• Milestones and expected results
• - preparation of an experiment (month 12)
• - data analysis of the experiment (month 28)
  delayed (Nov 06)
• - optimal post-acceleration energy
  estimation (33 month)

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Proposed experiment
FRS-GSI
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Proposed experiment
FRS-GSI

• Experiment proposal was submitted and approved
  by the
• GSI PAC (18 shifts 136Xe-parasitic and 18
  shifts 238U )
• Beam time expected scheduled July 2006 ? delayed
  until November

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Completed work during the first 18 months

• The experiment proposal was submitted and
  approved by the GSI
• PAC (18 shifts 136Xe-parasitic and 18 shifts
  238U )

• Detection setup plastic scintillator at S1
• - two fast photo-multipliers Hamamatsu
  H2431-50mod delivered
• to GSI last December
• - these photo-multipliers were tested in a
  beam time last April

• Detection setup tracking detectors at S2
• - TPCs will be used. New TPCs tested in a
  beam time last April

• Acquisition system new readout using the
  buffer memory of the
• CAEN converters
• - the system has been implemented and tested
  with 2 TDC 1 ADC
• - final implementation in the FRS DAQ after
  summer

• New on-line analysis based on Go4 implemented
  and tested

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Planned work for the next months

• Fix last details of the experimental setup
• - calibration requirements for TPCs
• - photo-multipliers at S2
• - removable target at S2

• Implementation and test of the new acquisition
  at the FRS

• Final schedule of the beam time constraints

• Detailed planning of the experiment
• - calculation of the magnetic tunings of the
  FRS
• - calibration planning with the 136Xe beam
• - definition of working teams

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Preliminary beam-time schedule at GSI
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Modifications of initial plans

• The beam time will be scheduled 9 months later
  than expected
• - all milestones of these subtask will be
  delayed by 9 months