NCharitonidis and YKaryotakis June 1st 2016 1 taking over the initial work from Ilias Efthymiopoulos H2VLE Beam Layout is final 2 Tilted Dipoles 35 degrees wrt xplane ID: 694149
Download Presentation The PPT/PDF document "The H2 VLE Beam Status report" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
The H2 VLE BeamStatus report
N.Charitonidis and Y.Karyotakis (*)June 1st 2016
1
(*) taking over the initial work from Ilias EfthymiopoulosSlide2
H2-VLE Beam Layout is final 2
Tilted Dipoles (~35 degrees wrt
x-plane)
WA105
Secondary dump
Courtesy:
S.Girod
, V.
Clerc
GEANT4 modelSlide3
H2-VLE beam line is finalized !
3Slide4
Simulation studiesGEANT4 based package (G4BeamLine)
Full simulation of H2 beam line transport + sec. target + VLE extensionWe generate 1M events per energy (5x27 hours on LAPP Tier2 per energy point ! Massive MC production)Physics lists studyBeam transmission studiesBeam Composition studiesTarget Optimization studiesMuon background studies
4Slide5
H2-VLE Beam
Secondary beam +80GeV/c (70% p, 25%p, 5% K on T22 Cu (30cm long and 3cm diameter))
Total beam line length after the target: L=39.644mBeam angles
a
x
= 11deg (horizontal plane)
a
y
=
,
7.7deg (vertical plane) assuming the target position at zero.Kaons and
pions decay soon/later before WA105 depending on their energy.In principle very low anti-proton production25%p, 5% K on T22 Cu (30cm) ta
WA105
WA105
5
T22
z
y
xSlide6
Beam composition at the entrance of WA105
Selecting Negative beam
Selecting positive beam
Electrons dominate at low energies
6
*
*
m
and positive particles are also producedSlide7
7Slide8
Simulated beam composition depends on Physics List !
In principle the list FTFP_BERT is recommended at low energies (<10GeV)
pion content
8Slide9
Proton content @ WA105
Anti-proton production is suppressed (FTFP_BERT) at low energies.9Slide10
Kaon content@ WA105
10Slide11
Muons in the beam pipe< 6%
11Slide12
Absolute Rates
The rate is adjustable by modifying the secondary beam intensity and / or collimating the beam
12
100 Hz trigger rate is easily achievableSlide13
Target optimisation
Target material = Cu
At high energy the content is almost independent from the target length
At low energy e+/e- are absorbed by using high Z targets and
p
’s production is enhanced
13
Target length = 15cmSlide14
Muon Background
Energy versus x
Energy versus y
Energy = +12 GeV
All muons in
LAr
considered
For 10
6
particles on T22, we find
+12GeV/-12GeV 11380/10896
m or ~2.5 KHzLow momentum (2GeV) must be cut from existing walls
14Slide15
Muon Background (2)
If the cryostat is moved higher by delta height, the muon background increases, a factor ~2 after dh = +500mm
15
Lateral shielding can easily be added before the bending magnetsSlide16
Material Budget
@ 1 bar
@ 1 bar
16Slide17
Data
taking durationUsing the less optimistic list FTFP_BERT and 30 cm Cu target
17
With W target significant reduction !Slide18
5402 mm
Z
Y
5402mm-817mm(=8548*cos(45
0
) * tan(7.7
0
) )= 4585 mm
4078 mm
Beam Position today
Bottom membrane
Beam
a
=7.7
o
18Slide19
Beam Instrumentation
Purpose :Provide triggerScintillator tilesBeam profile and momentum measurement event by event200 x 200 mm layers of fibers 0.5 mm combined with scintillator tilesPID2 Cherenkovs
at 15 barsTOF maybe
Space for instrumentation is very tight, close collaboration with the EN/EA and BE/BI people, non CERN equipment difficult to integrate
19Slide20
PID :2
Cherenkovs are enoughEverywhere more than 10 pe
Two meters long
Have to run @ 15bars
20Slide21
Two Threshold Cherenkov counters for complete PIDFreon 12
colorless, odorless, tasteless, nontoxic, and nonflammable21
Momentum Range
[GeV/c]
Particle
ID method
Info
0.4-0.8
Pions
No
Kaons or protons
?
Kaons
Protons
0.8-3.0
Pions
C1
C1 @ 15 bars
Freon
12, C2
empty
Kaons
No Kaons
Protons
No C1
3.0 – 5.0
Pions
C1 & C2
C1 @ 1.8 bars C2
@ 15 bars
Kaons
No C1 & C2
Protons
No C1 & No C2
5.0 - 8
Pions
C1 & C2
C1
@ 1 bar C2 @ 4.0 bars
Kaons
No C1 & C2
Protons
No C1 & No C2
8-12
Pions
C1 & No C2
C1
@ 1 bar C2 @ 1.8 bars
Kaons
No C1
&
C2
Protons
No C1 & No C2Slide22
L=31m
L=18m
TOF for p
/ p separation at low energies
Moderate TOF resolution needed ~1.5 ns
Electron pion separation with TOF at low energies
Need a 100ps resolution to tag e/
p
up to 2GeV/c
22Slide23
SummaryExtensive simulations finished for H2 and well advanced for H4
Physics list studyTarget optimizationBackground (muons)Momentum measurement (To be done)Material budget optimization in progress
Regular meetings with CERN instrumentation group (BE/BI) and joint ptotoDUNEs Beam group.
Need 2
Cherenkovs
at high (15 bars) pressure from CERN. On going discussions. Need decision before end of July
Detailed technical note under preparation due before June 16
th
2016
23