Mats Lindroos

ISOLDETechnical report for

INTC 21/5/2007

Mats Lindroos

Mats Lindroos

Outline

• Change of responsibilities at ISOLDE

• Shutdown work• Off-line upgrade• REX status• Technical R&D at ISOLDE

Mats Lindroos

New responsibilities at ISOLDE

• Technical coordinator– Richard Catherall

• REX ISOLDE superintendent– Fredrik Wenander

• ISOLDE hall superintendent– Erwin Siesling

• New projects and INTC matters– Mats Lindroos

Mats Lindroos

Major 2006/7 Shutdown tasks

• Yearly facility maintenance: water and power (HT)

• Instrumentation: migration to linux of scanners & wiregrids

• Front-Ends: repair of the boris-tubes insulators (R. Catherall)

• Mini-move: mini-ball into the extension 170 (D. Voulot)

• REX maintenance: upgrades and repair (F. Wenander)

• RFQ installation: prim pumps into HRS zone (E. Siesling)

• Various work: laser windows, PLC update, ADC replace,etc.

Mats Lindroos

Improvement on the shutdown

• Dedicated and responsible person appointed for each major task

• Weekly technical shutdown meeting

• Close follow-up and adaptation of the planning

• Daily start-up meeting at beginning of the run

Mats Lindroos

Results

• 2007 smooth start-up• No hardware failures or over-run of

work• Expected software debugging (i.e.

scanner & wiregrids applications)• BUT.. Unexpected (minor) controls

problems (PS wide, AB/CO addressed)

Mats Lindroos

Off-line separator upgrade

• New magnet coils to replace old faulty coils

• Survey points for the alignment of the offline separator installed and documented

• New beam diagnostic chamber with mechanical slit system and “ISOLDE type” scanner installed

• Special thanks to Jerome Sarret, Erik Asen, Antony Newborough, Michel

Duraffourg

Mats Lindroos

• Automatic mass program

• 15 minutes for masses 0-160 with 0.1 mass unit resolution

• Labview based control system communicating directly to PLC’s via RPC server

• Response time: CCV to PLC <900msRefresh rate 100ms

Mats Lindroos

REX low energy stage

• Trap– Operational and in standby mode. Minor improvements

during shutdown. Have delivered some stable beam to Witch.

• EBIS– The general power cut in March partly vented the machine

preventing us from doing further electron beam tests with the post anode.

– The newly inserted cathode did not perform as expected and had to be exchanged. 

• The machine is up running with a new cathode. Beam has been injected and extracted through the separator

• The old control system has been exchanged to a AB supported system. – Still running with a temporary application programme

Mats Lindroos

0.0

5.0

10.0

15.0

20.0

0 50 100 150 200 250

A

%

7Li238U

27Al

116Cd

Efficiencies for beams 2006Tot. eff. = Trap × BTS × EBIS × Sep

The constant “quest” for efficiency

REX low energy stage now covers A=7 to >200 with total efficiencies of at least 5%

High current beams can now be charge breed with some efficiency (e.g. 1.8% for a 3nA 7Li+ beam into 7Li3+)

Light ions still difficult to breed ≤5%

-> Charge breeder : generally aiming for 10% total efficiency!

-> Linac efficiency 70-85% (aim for >80% in 2007)

Mats Lindroos

Isotopes and elements run at REX so far…

8Li3+,9,11Li2+

10,11,12Be3+,4+

17F5+

24-29Na7+

29,31Mg9+, 28,30,32Mg8+ 68Ni19+

67-71,73Cu19+,20+,20+,19+

80Zn21+, 74,76,78Zn18+

70Se19+

88,92Kr21+,22+

108In30+

108,110Sn27+,30+

122,124,126Cd30+,31+

138,140,142,144Xe34+

148Pm30+

153Sm28+

156Eu28+

Mats Lindroos New section

Minimove - Phase 1

* Phase 1 = First phase of a full installation (linac upgrade, recoil separator, HIE-Isolde…)

* Goals : 1. create space (linac upgrade, space around experiments) 2. improve shielding from X-ray background at Miniball 3. improve beam properties -> more focussing -> more beam diagnostics -> realignment of beamlines

Installation in progress!

Mats Lindroos

Beam optics calculation 9-GP to MB target* 3MeV/u A/q3.5* 0.6π.mm.mrad normalised* ±1% energy spread

Diploma Thesis by T. Arronsson

Mats Lindroos

Y direction after 2.5m drift0.21 π.mm.mrad @ 2.2MeV/u

Linac emittance measurements

Results* Normalised transverse emittance (2σ RMS) = 0.21±0.07 π.mm.mrad at 2.2MeV/u

* Low intensity few 100pA (no space charge effect in EBIS!)

* Horizontal emittance larger than vertical after the bender (energy spread)

* Emittance increased when going from 1.2 to 2.2 MeV/u (mismatch between IHS and 7gaps?)

* Emittance increased with stripper foils

Energy spread = ±0.03MeV/u@ 2.97MeV/u (±1%)Continuation 2007

* Verify results with uninterrupted measurement series

* Verify influence of EBIS operation conditions on the emittance

* Measure at 3MeV/u and 300keV/u

Mats Lindroos

Technical R&D at ISOLDE

• Dual transfer lines– Merging of neutral

beams

• Mono ECR• Tendering for new

solid state laser for RILIS– Progress on LARIS

installation

• ECR PHOENIX charge breeder development

• RFQ cooler off-line commissioning

ResultsI/I

max

n+

bea

m

Plasma chamber high voltage

1+ beamExtraction

voltage

Noble gasMetallic ions

I/Im

ax n

+ b

eam

Plasma chamber high voltage

1+ beamExtraction

voltage

Noble gasMetallic ions

V tuning Stable backgroundMass Scan

-50

0

50

100

150

200

250

300

350

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0

A/q

I (n

A)

O4+O5+O6+C+C3+H+

Background >5nA 2<A/q<7

CW Pulsed

4<A/q<8=2-7%

CW 86Kr13+ 2.2%132Xe18+ 1%Preliminary

Afterglow

P. Delahaye et al., RSI 77 03B105 (2006)

86Kr13+

RFQ cooler “ISCOOL”

Emittance meter

RFQ cooler

Alkali ion source

Continuous mode

~5·mm·mrad 90% emittance

~30·mm·mrad 90% emittance

as input

Ion transmission

Li+ 17%

Na+ 27%

K+ 60%

Cs+ 70%

• Ongoing tests with the bunching mode• Last off-line tests with a FEBIAD source delivering noble gas ions

E. Mané, H. Frånberg,P. Delahaye