Sr and Ba MD run June 2007

Target issues
* UC2-C #355, Ta surface
* mass markers Sr, Ba, Ca, K
* separator setup at 30.2 kV

Yield check

ca 2-8pA stable beam seen on FC490 on mass 150. maybe 134Ba+16O ?
148Ba with        p on target: 1.2e4/muC               p on converter: 3.7e3/muC
96Rb with          p on target: 1.2e7/muC               p on converter: 5.4e6/muC
96Sr yield, much lower than 96Rb, cannot be determined because of major contribution
        from 96Rb
7 pA stable 115In / uC protons (-> difficult to tune REXTRAP so the molecules are kept
        as they are swamped by the 115In peak)
129Ba+19F contribution not estimated

REX issues

Fluorine molecules (136Ba+19F, 88Sr+19F, 96Sr+19F) broken into REXEBIS.

Stable isotopes accelerated:      

136Ba32+   (A/q=4.25    2.22 MeV/u)
period time 153 ms, no beam gate, breeding time 120 ms (not optimized for 32+, should
       be 150 ms)
Currents: Inj.plate=32pA, BTS.FC20=12pA, RFQ.FC20=21pA, L65.FC40=16 pA
Efficiency: HRS.FC490 to inj.plate=100%, Trap=37.5%, TRAP+BTS+EBIS+SEP=2%, LINAC=76%

88Sr21+   (A/q=4.19     2.21 MeV/u)
period time 51 ms, no beam gate, breeding time 48 ms (not optimized for 21+)
Currents: Inj.plate=67pA, RFQ.FC20=40pA, L65.FC40=31.5pA
Efficiency: HRS.FC490 to inj.plate=100%, TRAP+BTS+EBIS+SEP=2.8%, LINAC=79%

88Sr23+   (A/q=3.83       2.21MeV/u)
period time 101 ms, no beam gate, breeding time 98 ms (not optimized for 23+, should
       be 120 ms)

Currents: Inj.plate=115pA, RFQ.FC20=40pA
Efficiency: HRS.FC490 to inj.Plate=100%, TRAP+BTS+EBIS+SEP=3.2%

Radioactive isotopes accelerated:  

96Sr23+   (A/q=4.17    2.23 MeV/u)
period time 101 ms, breeding time 98 ms
Currents: very low, not seen on FC

Technical problems

* Trap electrode 14 still grounded…so still bad efficiency through the TRAP.
* Not enough time to set up 9GP so max energy was limited to 2.2MeV/u.
* Some RF problems on IHS and 7GP3. Can this explain poor transmission at higher A/q?