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MD report: IP aperture scans. P. Grenier, W. Kozanecki & M. Weaver + S. Ecklund's watchful eyes!. MD goals Experimental procedure HER-only x & y scans + high-current extrapolation [LER only X & y scans] + high-current extrapolation. MD goals. - PowerPoint PPT Presentation
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W. Kozanecki MDI meeting, 9 Mar 07
MD goalsMD goals
Experimental procedureExperimental procedure
HER-only x & y scans + high-current extrapolationHER-only x & y scans + high-current extrapolation
[LER only X & y scans] [LER only X & y scans] + high-current extrapolation+ high-current extrapolation
MD report: IP aperture scansMD report: IP aperture scans
P. Grenier, W. Kozanecki & M. Weaver
+ S. Ecklund's watchful eyes!
W. Kozanecki MDI meeting, 9 Mar 07
Quantify Babar Quantify Babar background sensitivitybackground sensitivity to IP x & y angles for to IP x & y angles for single beams (HER & LER separately, moderate currents)
collisions (moderate currents, then high currents)
and determine the and determine the optimum anglesoptimum angles (from the background (from the background viewpoint)viewpoint)
Cross-calibrateCross-calibrate LIPP & HIPP BPMs
Babar luminous & boost angles
against against support-tubesupport-tube (ST) BPMs (ST) BPMs
Determine LER IP Determine LER IP angles angles center of luminosity monitor center of luminosity monitor absolute angles (from ST BPMs) at moderate current
reference angles (from HIPP & LIPP), corrected for high-current operation
MD goalsMD goals
W. Kozanecki MDI meeting, 9 Mar 07
Locations of the IP BPMs & neutron monitorsLocations of the IP BPMs & neutron monitors
Neutron_bckw_1
Neutron_forw_1
Neutron_forw_2
CsI 7
Support-tube (ST) BPM HIPP BPM LIPP BPMLIPP BPM
W. Kozanecki MDI meeting, 9 Mar 07
(Intended)(Intended) Measurement SequenceMeasurement Sequence
SetupSetup colliding beams, offset by-2 patterns at 300 mA ea.
Single-beam scans: Babar onSingle-beam scans: Babar on HER
XP scan, then YP scan @ 300 mA, offset pattern
with XP & YP at optimum, raise IH as high as it will go, to measure current-dependence of support-tube (ST) - L/HIPP correlation
LER XP scan, then YP scan @ 300 mA, offset pattern
with XP & YP at optimum, raise IL until ST BPMs saturated
Luminosity-monitor scans: Babar onLuminosity-monitor scans: Babar on YP(e+) scan attempted; failed bec. IP Multiknob fbk not functional
Current-dependence of ST-L/HIPP correlation in collisionCurrent-dependence of ST-L/HIPP correlation in collision most likely different from single-beam (heat from both beams)
Background scans @ high current: XP(eBackground scans @ high current: XP(e--), YP(e), YP(e++), XP(e), XP(e++), YP(e), YP(e--)) beam-beam tails behave diffferently from beam-gas
W. Kozanecki MDI meeting, 9 Mar 07
Experimental procedureExperimental procedure
Operating procedure: generalOperating procedure: general manual scans, CRR plots vs time
monitor angles with ST BPMs, LIPP/HIPP orbit fits & monitoring fbks
monitor temps & vacuum throughout the scans
trickle, Babar on (incl. DAQ, with background-enriched trigger)
Initial setup: colliding beams, offset patterns, trickle, Babar onInitial setup: colliding beams, offset patterns, trickle, Babar on bunch patterns
LER: by-2, 300 mA, buckets 400-3400. BPM measdef @ bucket 3200
HER: by-2, 300 mA, buckets 0-3000. BPM measdef @ bucket 200
set initial IP angles based in May 2005 lumi-monitor settings (exc. XP-) LER XP = 9.25 mrad (ST BPMS) YP = - 1.1 mrad (ST
BPMs)
HER XP = -16.7 mrad (ST BPMS) YP = + 1.1 mrad (ST BPMs)
W. Kozanecki MDI meeting, 9 Mar 07
HER-only scans: current- & angle historyHER-only scans: current- & angle history
HER current XP_ST (e-)
YP_ST (e-)YP_ST (e-) during XP scan
W. Kozanecki MDI meeting, 9 Mar 07
HER-only scans: ST vs HIPP BPMs @ 300 mAHER-only scans: ST vs HIPP BPMs @ 300 mA
XP (orbFit) vs. XP_ST
XP (HIPP) vs. XP_ST
YP (orbFit) vs. XP_ST
YP (HIPP) vs. XP_ST
W. Kozanecki MDI meeting, 9 Mar 07
HER-only XP scan (1a)HER-only XP scan (1a)
Normalized to HER-only prediction
BW dmd, normalized
TR-23 (EMC)
E-collim (PR12 9082)
x 2.6x 1.7
x 2.3
W. Kozanecki MDI meeting, 9 Mar 07
HER-only XP scan (1b)HER-only XP scan (1b)
PR02 VP7032
PR02 VP8020
PR02 VP8029
CsI 3054
W. Kozanecki MDI meeting, 9 Mar 07
HER-only XP scan (2a)HER-only XP scan (2a)
neutron fwd_1
SVT occpcy, = 0 (E)
SVT occpcy, = 180 (W)
x 2.7x 3.6
x 11
W. Kozanecki MDI meeting, 9 Mar 07
HER-only XP scan (2b)HER-only XP scan (2b)
PR02 VP7034
PR02 VP7042
PR02 VP8027
PR02 VGH_8027
W. Kozanecki MDI meeting, 9 Mar 07
HER-only YP scan (1a)HER-only YP scan (1a)
neutron bwd_1CSi7052
Xcoll PR12 7102 Ycoll PR12 8072
W. Kozanecki MDI meeting, 9 Mar 07
HER-only YP scan (1b)HER-only YP scan (1b)
SVT occpcy, = 0 (E)
SVT occpcy, = 180 (W)
W. Kozanecki MDI meeting, 9 Mar 07
HER-only YP scan (1c)HER-only YP scan (1c)
PR02 VP8027
PR02 VP8020
PR02 VGH_8027
W. Kozanecki MDI meeting, 9 Mar 07
HER-only YP scan (2)HER-only YP scan (2)
neutron fwd_1
TR-23 (EMC)
BW dmd, normalized
Normalized to HER-only prediction
W. Kozanecki MDI meeting, 9 Mar 07
HER-only YP scan (3)HER-only YP scan (3)
neutron fwd_2 CSi3054
PR02 VP8024
W. Kozanecki MDI meeting, 9 Mar 07
High-current extrapolation: HER-onlyHigh-current extrapolation: HER-only
HER current XP_ST (e-)
YP_ST (e-)
W. Kozanecki MDI meeting, 9 Mar 07
HER-only YP scan (4)HER-only YP scan (4)
E-collim (PR12 9082)
PR02 VP8029
W. Kozanecki MDI meeting, 9 Mar 07
High-current extrapolation (HER-only): ST vs HIPPHigh-current extrapolation (HER-only): ST vs HIPP
XP (HIPP) vs. XP_ST (e+) YP (HIPP) vs. YP_ST (e+)
XP (HIPP)
W. Kozanecki MDI meeting, 9 Mar 07
High-current extrapolation (HER-only) (1a)High-current extrapolation (HER-only) (1a)
TR-23 (EMC)
BW dmd, normalized
E-collim (PR12 9082)
Dynamic pressure
W. Kozanecki MDI meeting, 9 Mar 07
High-current extrapolation (HER-only): pressure samplingHigh-current extrapolation (HER-only): pressure sampling
Thermal outgassing
W. Kozanecki MDI meeting, 9 Mar 07
High-current extrapolation (LER-only): angles vs. IHigh-current extrapolation (LER-only): angles vs. I
XP_ST (e+)
YP_ST (e+)
LER current
W. Kozanecki MDI meeting, 9 Mar 07
High-current extrapolation (LER-only): ST vs. LIPPHigh-current extrapolation (LER-only): ST vs. LIPP
XP_ST (e+)
YP_ST (e+)
XP (YIPP) YP (LIPP)
W. Kozanecki MDI meeting, 9 Mar 07
To do…To do…
Document usable scan rangesDocument usable scan ranges first pass (PG) @
http://www.slac.stanford.edu/BFROOT/www/Detector/Backgrounds/ApertureScan-05Mar07.html
supply tables of XP(LER/HER, ST BPMS) vs. time stamps
Detailed analysis for each subdetectorDetailed analysis for each subdetector SVT occupancies, DCH current + occupancies, DIRC scalers &
currents - use normalized quantities (2004) wherever possible
clean up data sets (e.g. remove spikes associated with LER LFB problems, with knob turning, etc)
how well does the 'family' concept hold?
Analyse temperaturesAnalyse temperatures
Analyse vacuum signaturesAnalyse vacuum signatures
Volunteers needed!Volunteers needed!
W. Kozanecki MDI meeting, 9 Mar 07
Summary (preliminary!)Summary (preliminary!)
Background sensitivity to single-beam aperture scans @ 300 mABackground sensitivity to single-beam aperture scans @ 300 mA significant, may explain part of the discrepancy w/ Jan '04 norm'lztn;
is different, in both magnitude & optimum, for different subdetectors. The overall background optimum is incompatible with the SR load, at least in the HER (LER tba)
There may be subdetectors 'families' that depend on X/Y, HER/LER; within one scan, several sources are at work, depending on the direction of SR fans & local aperture restrictions.
Consistency between ST BPM's & LIPP/HIPPConsistency between ST BPM's & LIPP/HIPP much improved since run 5
degrades as current increases, esp. for LER XP
Luminosity monitor scanLuminosity monitor scan could not be completed for lack of working IPO Multiknob feedback.
Can the fast dither play the same role? We need to know the center!
may yield LER IP angles different from the single-beam optimum.
No reason to believe that this single-beam optimum will coincide No reason to believe that this single-beam optimum will coincide with that for beam-beam tails: with that for beam-beam tails: need to explore XP & YP need to explore XP & YP optimization on both L and backgrounds under physics optimization on both L and backgrounds under physics conditions!conditions!
W. Kozanecki MDI meeting, 9 Mar 07
AppendixAppendix: CRR plot files & data sets: CRR plot files & data sets
PEP-II e-log: 5 March 2007 day + swing shiftPEP-II e-log: 5 March 2007 day + swing shift See also
http://www.slac.stanford.edu/BFROOT/www/Detector/Backgrounds/ApertureScan-05Mar07.html
for scan times & ranges
CRR button filesCRR button files BBR_BKG_LERIPORB.btn
BBR_BKG_HERIPORB.btn
BBR_ALL_BKG.btn
All data in PHYSICS_DATA:[pep2.char.05mar07]All data in PHYSICS_DATA:[pep2.char.05mar07]