Post on 08-Jan-2016
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Plans (& ideas) for beamline commissioning
• The beamline• Magnet field tests• Source characterisation• Optics (& model) commissioning
K. TilleyCM18, 14/06/07
The beamline until Jan? (this presentation)
‘please sir’
Magnet field tests – Upstream: Q1-3 & B1
Upstream Possible – In test area: QIV(s), (B1 – less likely)Sometime 18/06 – 01/07 –currently being discussed
Upstream Fallback – In situ: QIVs, B1By negtd access August?
Magnet field tests – Upstream Possible
In test area: QIV x1+, (B1 – less likely). being discussed for 18/06 – 01/07
eg: QIV before installation.- Pole tip fields v Current to 200A (cf. old g.v.I data) (compare to old data curve)- deGauss procedure (to 200A)- Gross magnetic centre (with Mr Heath Robinson)
Currently searching for XY translation stage/support-- for improved versions of all above- L_eff & field quality – unlikely.
Magnet field tests – Upstream Fallback
In situ: QIVs, B1. By negotiated access August?
- for QIVs:-- polarity (Hall probe between poles)- deGauss procedure? (ditto: desire minml jig?) - others are more difficult (but may try).
(note do have old g.v.I data)- for B1:-
- polarity- B.v.I – some access (desire miniml jig?)
(note do have old B.v.I data) - deGauss procedure
Magnet field tests - Downstream
Same plan as CM17 – B2, Q35s
Unchanged procedure & measurements:- we have no B.v.I tables for Q35s- use XY stage/jig (for Q35s)...- still need someone to make jig.
Timeframe – If B2 to be used Aug onwards – measureAugust?! Q35s sometime Sept – Dec?
Location – undefined. Test area if pre Dec? MICE Hall once installed?
Magnet field tests – Decay Solenoid
Discovered I don’t have any B.v.I tabulation !
Does PSI have these? (could we measure these? eg. fringe field & model?)
Source characterisation – naïve ideas
Source characterisation – naïve ideas
Once beam, could consider using available detectors to tell us something about particle source, ie:-
- Determine intensity (au) of whole flux versus momentum
- Range out protons & determine intensity (au) of (∏ +µ+e) versus
momentum
- Range out protons & use Ckov1, later TOFs to: determine intensity (au) of ∏ versus momentum
- Knowing ~ intensity (au) may help beamline setup for maximum flux etc.
Source characterisation – naïve ideas
Once beam, might consider using available detectors to tell us something about particle source, ie:-
- Determine intensity (au) of whole flux versus momentum
eg. (preceeding optics setup):-
- use upstream fibre monitor for intensity (au)- use momentum scan of B1 (Quads off)
Source characterisation – naïve ideas
If synch vault was still accessible could also:-
- Determine intensity (au) of (pi+mu+e) versus momentum:-
eg. (preceeding optics setup)
- insert protons absorber before u/str monitor- use momentum scan of B1 (Quads off)
If synch vault or DSA not accessible, but B2 available, could perform same experiments with d/stream monitor, scanning both dipoles (B1=B2)
Source characterisation – naïve ideas
For even more fun, bring in Ckov1 / (later TOFs?) into play ?:-
- Determine intensity (au) of (pi) versus momentum ?:-
eg. (again preceeding optics setup)
- insert proton absorber before d/str monitor- use Ckov1 count how many hits not pi’s. diff =
pi’s- much easier if TOF available!- use momentum scan of B1 (Quads off)
(Does this work? I told you I was naïve !)
Optics (& model) commissioning
Aim maybe to get the real optics into the design configuration.This might be:
Q1'
Q2'
Q3'
IWin
AIR
BWin
USDW
Q4PN
.or something slightly different nowadays.Aim to get this section understood & right
Optics (& model) commissioning
Start with best avail model (TTL/g4bl) – best developed & cross checked.
Make simple expts and compare measurables to model – to establish we understand basic beam/model behaviour.
Potential measureables:-upstream monitor: vertical beamsize
(vertical position) flux
if DSA available, use d/str mtr there: vertical beamsize (vertical position) flux.
could use both monitors:-> vert opt fns & εv?I don’t know how to measure horizontalbeamsize/posn directly (only via flux)
Optics (& model) commissioning
Example: Q1 on, Q2/Q3 off. B1 on. Vary Q1. Observe change in vertical beamsize/optic fns/ εv Compare with model expected behaviour. Could fit model to machine. (L_eff etc)
Vary target depth. Repeat above. Observe if any change in vertical position (source
position)
Finally bring up Q1-Q3 as single lens. Modify Q1-Q3 using model until believe obtain design
optic.