analysis meeting: beam momentum measurements using tofs tuesday, 22 january 2008 slide 1 of 10 beam...
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Analysis meeting: Beam momentum measurements using TOFs Tuesday, 22 January 2008 Slide 3 of 10 Stage 2 G4MICE simulation 100 muons from Kevin’s realistic TURTLE beam:100 muons from Kevin’s realistic TURTLE beam: –Blue – positively charged particles, mainly mu+ –Red – negatively charged particles, mainly e- –Green – neutral particles, mainly photons TOF0 Cherenkov Q7 Q8 Q9 TOF1 Tracker 1TRANSCRIPT
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 1 of [email protected].
uk
Beam momentum measurement using TOFs: progress report
Analysis meeting, 22 January 2008Mark Rayner – Oxford/RAL
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 2 of [email protected].
uk
Beam parameters at Tof-0
MICE Beam Line Design, Kevin Tilley, 16-XI-07
Kevin’s realistic
TURTLE beam of muons has
been propagated starting at
TOF0 by the G4MICE
simulation code
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 3 of [email protected].
uk
Stage 2 G4MICE simulation
• 100 muons from Kevin’s realistic TURTLE beam:100 muons from Kevin’s realistic TURTLE beam:– Blue – positively charged particles, mainly Blue – positively charged particles, mainly
mu+mu+– Red – negatively charged particles, mainly e-Red – negatively charged particles, mainly e-– Green – neutral particles, mainly photons Green – neutral particles, mainly photons
TOF0 CherenkovQ7 Q8 Q9 TOF1 Tracker 1
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 4 of [email protected].
uk
TOF0 & Cherenkov
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 5 of [email protected].
uk
Quadrupoles 7, 8 and 9
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 6 of [email protected].
uk
TOF1 & Tracker 1
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 7 of [email protected].
uk
Amplitude analysis of muons surviving to TOF1
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 8 of [email protected].
uk
Momentum reconstruction• Reconstruction class TofTrack being added to G4MICE
– In close collaboration with Malcolm– Very simple to begin with– Designed to be useful before trackers are operating– Details to follow at CM20– The following work is a look beyond that at the difficulties of
doing something more sophisticated • The following numbers are Monte Carlo truth…
– Designed to illustrate the intrinsic difficulties in reconstructing momentum given TOF0 and TOF1 data
• No time measurement error• No transverse position measurement error
• Neglect corner clippers– Use hit with most photoelectrons
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 9 of [email protected].
uk
Path between Tof-0 and Tof-10.48 m
Tof-1(same design for Tof-2)
Tof-0
0.48 m
Actual path
Straight line
between space points
Straight line
between Tof centres
muons
r0=(t0, x0, y0,z0)|MC
r| = {(x1-x0)2+(y1-y0)2}
Some definitions:pMC
TOF1Pcrude guess = |m
where = (r1-r0)/[(t1-t0)c]
pMCTOF1
pCrude guessCorrection
factor =
r1=(t1, x1, y1,z1)|MC
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 10 of [email protected].
uk
Prospects for momentum reconstruction
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 11 of [email protected].
uk
Extra Slides
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 12 of [email protected].
uk
Transverse phase space: horizontal
x / cmpx / MeV
-40 cm – 40 cm-100 MeV – 100 MeV
x
px
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 13 of [email protected].
uk
Transverse phase space: vertical
y / cmpy / MeV
-40 cm – 40 cm-100 MeV – 100 MeV
y
py
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 14 of [email protected].
uk
Longitudinal phase space
Analysis meeting: Beam momentum measurements using TOFsTuesday, 22 January 2008
Slide 15 of [email protected].
uk
Momentum measurement uncertainty
• p = m0 c – assume PID ascertains m0
• Timing uncertainty– Technical challenge: progress being made in Milano
• One counter = scintillator with 2 PMTs– “…a conservative request for single counters timing resolution is 60–70 ps”
» MICE Note 145• Other factors:
– 2 planes per station» Rotated so as to yield ‘space points’
– Multiple space points per muon possible/likely• t1–t0 will be larger still
• Path length uncertainty– Software challenge: challenges remain…
• Multiple scattering in Tof-0, Cerenkov, Tof-1 and air• Focusing in quadrupoles Q7, Q8 and Q9• Limited transverse position resolution