T-980 Crystal Collimation Recent Results T-980 Collaboration: FNAL, SLAC, BNL, CERN, PNPI, IHEP, INFN

1
T-980 Crystal Collimation Recent ResultsT-980
CollaborationFNAL, SLAC, BNL, CERN, PNPI, IHEP,
INFN

• D. Still
• CM14
• April 27, 2010

2
Overview

• Brief T980 History and Purpose
• Experimental Setup
• Initial results from Multiple Volume Reflection
  (MVR)
• Comparison of MVR results with simulations
• Summary

3
Explanation of Crystal Channeling
4
Vertical Multi-Strip Orientation
This orientation is opposite of what was
calculated and estimated.
Name MS-08-09 Bend 63urad (VR) 8 strips
5
Overview

• Brief T980 History and Purpose
• Experimental Setup
• Initial results from Multiple Volume Reflection
  (MVR)
• Comparison of MVR results with simulations
• Summary

6
T980 Setup in Tevatron E0 for 2009-2010
Detectors Abort gap (TE1LABT) Bunch (TE1LBNC)
Pin detector (TLE0PIN)
Vertical
F1 detectors Abort gap (TF1LABT) Bunch (TF1LBNC)
7
New Vertical Goniometer
Up and Downstream Motion control and LVDT
Up and Downstream Laser angle measurement
instruments
8
New Characterized Crystals
New
New
Name MS-08-09 Bend 63urad (VR)
Name O-05-09 Bend 360urad Miscut 120urad
Installed Ver Dnstrm goniometer
Installed Hor goniometer
Name O-BNL-02 Bend 410urad Miscut 1600 urad
Installed Ver Upstrm goniometer
9
Goniometer Installations over Summer 09 Shutdown
Newly built and installed (Summer 2009) Vertical
goniometer at E0. It is 4m upstream of the Hor.
one. Ver. goniometer houses old O-shaped crystal
(reversed for negative miscut) and multi-strip
crystal.
Modified horizontal goniometer. Replaced old
large-miscut angle O-shaped crystal with new
small miscut O-shaped during Summer 2009.
10
Location of Vertical multi-strip CH VR beam
Displacement of CH beam at Collimator is 6.0 mm
Displacement of VR beam at E03 Collimator is
1.76mm
11
Overview

• Brief T980 History and Purpose
• Experimental Setup
• Initial results from Multiple Volume Reflection
  (MVR)
• Comparison of MVR results with simulations
• Summary

12
MS-08-09 Characterizations at Cern North Area
RD22 H8, 400 GeV/C protons
Name MS-08-09 Bend 63urad (VR) Bend 200urad
(CH) 8 strips
CH
AM
AM
VR
Crystal angle
13
Vertical Multi-strip Angular scan
E03V and F172V Collimators in at max catch
CH
VR
AM
14
VR beam collimated w/ E03V is consistent
(only if F17 is in)
1.76mm displacement Corresponds to VR
angle ?1.76mm/28m 63 urad Cern H8 measured
angle 93 urad/ sqrt(980/400)59 urad Width is
39 urad thats wider than expected SPS
18sqrt(980/400) 29 urad .
VR beam displaced 1.76mm from core with a sigma
of 1.122. F172 collimator is in at max catch.
(Analysis by Vladimir Shiltsev)
15
CH beam collimator scan w/ F172 collimator -
(E03 is in)
Angle of Bend for CH Corresponds
to ?1.87mm/29m 65 urad instead of 200
urad Width is 28 urad thats narrower? than
expected
(Analysis by Vladimir Shiltsev)
10/14/2015
V.Shiltsev - T980
16
MS Crystal Angle Scan LE0PIN Loss rate
Calculated Efficiency90 If CCVAD calibration
coefficient is 1.24 ?(CCVAD-500) 1.24 Total
width 550 urad High Eff width 100 urad
10/14/2015
16
V.Shiltsev - T980
17
Overview

• Brief T980 History and Purpose
• Experimental Setup
• Initial results from Multiple Volume Reflection
  (MVR)
• Comparison of MVR results with simulations
• Summary

18
Simulated Data S. Drozhdin Beam
Collimation in the Tevatron Using Multi-strip
Protvino Channeling Crystal
19
Qualitative Look at Experimental vs. Simulated
Data
CH peak also aligns
VR Beam collimated at E03V
Align
CH beam collimated at F172V
Good
Need better understanding of these areas.
20
Losses at Crystal are not consistent with
Simulation
21
Experimental Data does not have loss at F0
Lambertson
22
What is missing from Real data to Simulation?????

• Are there process that are not taken into account
  in simulation? Multi-turn effects, crystal
  problems, crystal inefficiencies, skewed planes,
  beam loss at additional apertures, physics
  missing from simulations?????
• The problem seems to be most wrong in the AM part
  of crystal, then next boundaries between VR and
  CH.
• Went back to Drozhdin paper to look in detail.
  Noticed that simulations are done for 20 turns.
  After talking with Sasha, once a particle is lost
  it is gone. Therefore number of particles is
  shrinking and it takes more (many more ) turns
  for a particle to be lost in the AM part.
  Therefore, we are not really estimating real data
  to simulation in area not in CH or VR.
• Sasha reran simulation to take AM with
  circulation beam.

23
Modified original simulations to include estimate
for multi-turn losses at amorphous angles
24
Experimental and simulated losses at the crystal
25
Experimental and simulated losses downstream E03
collimator
26
Experimental and simulated losses downstream of
F172 collimator
27
Summary

• Demonstrated CH and VR with the vertical
  multi-strip crystal MS-08-09 at 980Gev.
• Collimator scans measure the VR angle at E03V at
  63urad in good agreement with estimated crystal
  VR bend but some error from 59urad characterized
  at Cern H8.
• Collimator scans measure the CH angle at F172Vat
  65urad instead of H8 results of 200urad.
  Uncertain the cause of this error. In both VR and
  CH scans, both E03 and F172 need to be in to
  produce reasonable results.
• Qualitative comparison of experimental data and
  simulated data has better agreement when better
  multi-turn beam loss estimates for crystal angles
  in the amorphous angles were applied. Further
  simulations will be run with increased number of
  turns.