Advanced CB

1
Plan for the extension of 12 month for JRA03
Double frequency operation of PHOENIX at LPSC
(chamber is now available, simpler setup than 28
GHz operation) Further exploration of charge
state manipulation and comparison with the new
simulation tool CBSIM. Efficiency exploration
with BNL EBIS (can only be done in 2008)
Continuation of molecule break up and capture of
decay products, which opens new possible beam
development
2
Task 4 High-frequency exploration of ECRIS 4.1
Improving of breeding time of ECRIS already seen,
to be measured systematically before
interpratation 4.2 High frequency (14-28 GHz)
exploration 28 GHz might be difficult before end
2008 4.3 Influence of ECRIS plasma volume Double
frequency (1418 GHz will be a good test)
Modifications of the booster under fabrication,
will installed by the end of September 2007
3
ECRIS charge breeders pulsed
ECR charge breeding time
LPSC
28 GHz, 3600 W
18 GHz, 950 W
T. Thuillier et al., ICIS07
Steady states reached at 3 ms for all charges !!
4
Shift of the charge state spectra to higher
charge states
Can be done by fast removalof hot low charged
ions ? cooling effect
In Bari ? rf-excitation (BRIC) MAXEBIS ?
reduced barrier Uni Frankfurt ? fast variation
of electron beam current
5
Charge state manipulation methods?

• Using atomic shell structure Beneficial
  only for heavy ions until now (REXEBIS) ?
  Very high abundance in on charge states in EBIT,
  but at the expense of low efficiency
• Using DR resonances In principle possible
  (shown at Heidelberg EBIT), but efficiency
  spoiled by energy spread of the electron beam.
• Cooling of highly charged ions Works for
  medium heavy and heavy elements ? survey
  required

6
Simulation tool CBSIM
Included so far Collision physics Stepwise
ionisation,charge exchange, RR Collision and
trap physics electron-ion-heating,ion-ion
cooling
Without charge exchange and recombination, but
ion losses
With charge exchange and recombination
Included so far Trap physics space charge
neutralisation andion losses Soon atomic data
tables
7
Molecule breakup (EBIS)
Molecular sideband beams from ISOLDE to
avoid isobaric contamination e.g. 70SeCO to
avoid 70Ge Keep molecules inside trap, break
them in EBIS (or break inside trap with
different trap potential settings)
Results 50 SeCO out of trap 6.5 SeCO to
Se19 in EBIS (58 ms breeding time)
Problems inside the EBIS ions with high
electro-negative values escape the electron
beam Also tried SrF, BaF, AlF (gt16 total
efficiency for Al7)
8
61Mn trapping and ejection

• Measurement cycle
• RF on, plasma ignited

• 61Mn injected into the ECR

• RF is kept on for a time that can be varied (0s,
  800ms)

• Ejection of the ions as a pulse

9
Emittance measurements ECRIS
Two 1 and two n identical emittancemeters are
setup in the beam Line of LPSC and are working ?
RMS emittances absolute (20 kVq)
Xplane 84Kr15
Y plane 84Kr15
Xplane 84Kr1
Y plane 84Kr1
norm 0.06 mm mrad
norm. 0.015 mm mrad