30Mg run Oct 2007 (25/10->03/11)

 

Target issues:

* #367  UCx, MK8

* Mg mass marker

* GPS separator

* Yield values:

            Yield measurement gave            

                        22/10: 1.8E+06 At/uC (estimated contamination from 30Al is ~10%)

                        31/10: 1.0E+06 At/uC (and 9E+04 At/uC without laser)

                        02/11: >0.5E+6At/uC (estimate)

            The experiment estimated 1-5E+04/s

 

Experimental issues:

* Miniball

* IS454

 

 

REX issues:

breeding time, efficiency and currents:    

 

27Al7+ (stable):
Tperiod= 20 ms, Tbreed=12 ms, no gate

Icoll=168.6 mA, Ugun=4000 V

Trap inj plate=8.5 pA, RFQ.FC20(7+)=4.3 pA 

Efficiency(Trap+BTS+EBIS+sep, 7+)=7.2%

normal extraction

 

 

30Mg7+ (radioactive):

Tperiod=20 ms, Tbreed=14 ms

Icoll=169.4 mA, Ugun=4000 V

With 14/28 pulses, 1.5E+13 ppp

Beam cannot be seen on FC but can be seen on MCP

normal extraction

 

Linac transmission and energy:

For A/q=4  transmission 85% energy 2.86 +/- 0.03 MeV/u

 

Technical problems:

* XL65.BO60 was not working

 

Comments and lessons learned

* always monitor radiation levels around the machine after the radioactive beam is set-up to have  some reference values during the run

* diamond detector and “collimator” used for the first time at Miniball to optimize the beam