rpc project update on the trigger
DESCRIPTION
RPC project Update on the trigger Two members of the RPC group are active in the trigger simulation to review and cross check all the figures Production of gaps The production of CMS gaps has started. Tests in Summer/Autumn 2001 Irradiation with gammas and neutrons - PowerPoint PPT PresentationTRANSCRIPT
RPC project
Update on the trigger Two members of the RPC group are active in the trigger simulation to review and cross check all the figures
• Production of gaps The production of CMS gaps has started.
• Tests in Summer/Autumn 2001 Irradiation with gammas and neutrons DT-RPC test RPC-Link Board test
RPC project
Update on the trigger Two members of the RPC group are active in the trigger simulation to review and cross check all the figures
• Production of gaps The production of CMS gaps has started.
• Tests in Summer/Autumn 2001 Irradiation with gammas and neutrons DT-RPC test RPC-Link Board test
50 Hz/cm2
Neutron factor 3
10%
100%1/0 5 1/041/031/02
70%
01 02 03 04 05 06
1/06
120 RB1, 120 RB2, 120 RB3, 40 RB4
80 RB4
Install. Milestones (V.31)
# of chambers needed for install. in SX
Trialwheel 0 7/04
readiness wheel +2 8/03
Readiness wheel -2 8/04
End of SXinstallation 12/04
End of UXinstallation 6/05
< install. of wheels 0 ,+1 >
end +2 +1,0 2/04
< installation of wheels +2, -1, -2>
Begin mass production 9/ 01
500 gap
Maggio 02
500 gap
Maggio 02
820 gap
Febbraio 03
820 gap
Febbraio 03
Gap production at GT
So far 40 gaps (RB3 type) have been produced). The goal is to have 100 gaps ready for the end of the year.
Quality control: • pressure test up to 20 mbar• HV test up to 8000 in pure C2H2F4 ( I < 3A)• Quality of the oil coating ( by opening 1/10 of chambers)
Plan for next year: J F M A M J J A S O N D 40 140 240 330 450 500 550 600 650 650 650 650
Bakelite procurement: 300 foils arriving at GT in January 300 in production in January
Gap production at GT
So far 40 gaps (RB3 type) have been produced). The goal is to have 100 gaps ready for the end of the year.
Quality control: • pressure test up to 20 mbar• HV test up to 8000 in pure C2H2F4 ( I < 3A)• Quality of the oil coating ( by opening 1/10 of chambers)
Plan for next year: J F M A M J J A S O N D 40 140 240 330 450 500 550 600 650 650 650 650
Bakelite procurement: 300 foils arriving at GT in January 300 in production in January
Assembly at GT
Double gap assembly foreseen at GT. Tools in preparation.Assembly should start very soon, but space, resources and schedule at GT still to de defined. The option to use additional INFN manpower for the assembly has been very preliminary discussed in the INFN RPC committee
Chamber assembly at GT: Idem
Chamber assembly in Sofia : ready Chamber assembly in Pavia: site in preparation
Chamber assembly in Bari: ready
Assembly at GT
Double gap assembly foreseen at GT. Tools in preparation.Assembly should start very soon, but space, resources and schedule at GT still to de defined. The option to use additional INFN manpower for the assembly has been very preliminary discussed in the INFN RPC committee
Chamber assembly at GT: Idem
Chamber assembly in Sofia : ready Chamber assembly in Pavia: site in preparation
Chamber assembly in Bari: ready
DT + RPC under tested at ISR
DT + RPC at GIF
Combined DT-RPC testCombined DT-RPC test
Efficiency Efficiency
s
ss
P
P
1
No SF6; data with SF6 being analysed No SF6; data with SF6 being analysed
Rate from cluster countingRate from cluster counting
Efficiency 99%
Strip # is fired if it the median of the considered cluster
Strip # is fired if it the median of the considered cluster
No SF6; data with SF6 being analysed No SF6; data with SF6 being analysed
Hit countingHit counting Cluster sizeCluster size
No SF6; data with SF6 being analysed No SF6; data with SF6 being analysed
even
ts
Distributions of residuals between reconstructed impact point from DT and the median strip in the RPC cluster
Spatial resolutionSpatial resolution
Gamma irradiation @ GIFGamma irradiation @ GIF
“Oiled” chamber at GIF from October 2000 to May 2001:• Monitor rate and current• Study the efficiency to cosmic
“Oiled” chamber at GIF from October 2000 to May 2001:• Monitor rate and current• Study the efficiency to cosmic
Before irradiationBefore irradiation
Two month after irradiationTwo month after irradiation
Efficiency Efficiency
Rate Rate
Monitor the chamber at different source conditions (ABS)Monitor the chamber at different source conditions (ABS)
NABS = number of hit
expected at a given ABS, as computed by the simulation
The system resistance remains constant during irradiation
The system resistance remains constant during irradiation
If R is the total resistance of the system,the quantity Hvgas should be invariant:
If R is the total resistance of the system,the quantity Hvgas should be invariant: HV HVgas
LegnaroLegnaro (Padova INFN) (Padova INFN)
1717CiCi 252 252Cf:Cf:
a-3%a-3% spontaneous fission;spontaneous fission;
b-b-97%97% decay decay
1 gap oiled1 gap not oiled1 gap oiled1 gap not oiled
3.8 n/fission3.8 n/fission
EEavav= 2.14 = 2.14 MeVMeV
Neutron irradiation Neutron irradiation
Measure the sensitivity to low energy neutrons
Measure the sensitivity to low energy neutrons
Lovain Centre de Recherches du Cyclotron (Louvain la Neuve, Belgium)
Reaction: 9Be (d,n)
Neutron Flux at 90 cm:
8.15 107 n/cm2 s A
3 double gap RPCs
Neutron irradiationNeutron irradiation
90 cm from the target
Single gap sensitivity at low energy: (2.5-3.5) 10-4
Single gap sensitivity at high energy: (2-3) 10-3
Same chamber used for both measurements
No difference between the oiled and the no oiled gaps
Single gap sensitivity at low energy: (2.5-3.5) 10-4
Single gap sensitivity at high energy: (2-3) 10-3
Same chamber used for both measurements
No difference between the oiled and the no oiled gaps
Neutron sensityityNeutron sensityity
Double gap sensitivity is twice the single gap value
Double gap sensitivity is twice the single gap value
1 gap with oil coating
(Resistivity: 1.4 1010
cm)
1 gap without oil coating
(Resistivity: 3.2 109 cm)
Gas mixture: 96.5% C2H2F4
3.5% i-
C4H10
1 gap with oil coating
(Resistivity: 1.4 1010
cm)
1 gap without oil coating
(Resistivity: 3.2 109 cm)
Gas mixture: 96.5% C2H2F4
3.5% i-
C4H10
The Neutron Flux can be adjusted by tuning the current of the beam:
at 90 cm= 8.15 107 n/cm2 s A
The Neutron Flux can be adjusted by tuning the current of the beam:
at 90 cm= 8.15 107 n/cm2 s A
n ageing @Louvain n ageing @Louvain
# Measurements Dose (Gy)
Charge (C/cm2 gap)
n fluence (n/cm2)
1 0 0 before irradiation
2 4 710-4 2 1011
3 50 0.002 1 1012
4 50 0.002 After irradiation
# Measurements Dose (Gy)
Charge (C/cm2 gap)
n fluence (n/cm2)
1 0 0 before irradiation
2 4 710-4 2 1011
3 50 0.002 1 1012
4 50 0.002 After irradiation
Irradiation schedule
High neutron fluxes (2-3 107 n/s cm2)
High neutron fluxes (2-3 107 n/s cm2)
Chamber noise monitoringChamber noise monitoring
At constant neutron flux the contribution of the neutron activation must be added.
At constant neutron flux the contribution of the neutron activation must be added.
The chamber noise is decreasing following the decay law
The chamber noise is decreasing following the decay law
0
500
1000
1500
2000
2500
3000
0 5 10 15 20 25 30 35 40 45 50
Irradiation time(min)
rate
(H
z/cm
2)
non oiled GAP
BEAM ON
BEAM OFF
oiled gap
-
20
40
60
80
100
8 8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 10 10.2 10.4 10.6 10.8
HV (kV)
Effic
ienc
y (%
)
Before irradiation
After Irradiation
oiled gap
00.5
1
1.52
2.53
3.5
44.5
5
8 8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 10 10.2 10.4 10.6 10.8
HV (kV)
rate
(H
z/cm
2)
Before Irrad.
After Irrad.
The chamber efficiency was measured using cosmic muon triggers
The chamber efficiency was measured using cosmic muon triggers
Efficiency and noise: before after irradiationEfficiency and noise: before after irradiation
Non oiled gap
0
1020
30
40
5060
70
80
8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 10 10.2 10.4
HV (kV)
Ra
te (
Hz/
cm
2)
Before irrad.
After irrad.
Non oiled gap
-
20
40
60
80
100
8.2 8.4 8.6 8.8 9 9.2 9.4 9.6 9.8 10 10.2 10.4 10.6
HV (kV)
Rate
(H
z/c
m2)
Before irrad.
After irrad.
Conclusion Conclusion
• Satisfactory results on the performance of the RPC system
• Barrel production has started
• The schedule at GT needs some refining
• Man power required (art. 2222)
• Specification for the gas system defined (tender ready to go)
• Pavia site in preparation
• Satisfactory results on the performance of the RPC system
• Barrel production has started
• The schedule at GT needs some refining
• Man power required (art. 2222)
• Specification for the gas system defined (tender ready to go)
• Pavia site in preparation