Roman Pot Project
http://totem.web.cern.ch/Totem/
Design and integration
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
Marco Oriunno, CERN
19 September 2005
Some facts….
http://totem.web.cern.ch/Totem/
The mechanical prototype 2004 has proven to work well -> upgrade for LHC
• Integration of one horizontal pot
• Integration of one dedicated BPM
• Enlarged size of the pot
• Thin window with improved flatness (~ 50 microns)
• New concept for the integration of cables and cooling
• Choice of Motors - LHC graded
• Vacuum issues
• RF issues
• LHC Integration issues
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
19 September 2005
TOTEM Roman Pot
Final design of the Roma pot Unit:
http://totem.web.cern.ch/Totem/
•Upgrade of the Prototype tested in the SPS in 2004
•Vertical and Horizontal units interconnected by a bellow
•Dedicated Beam Position Monitor integrated in the unit
•Pre-series production ready to start in Czech Republic
•First unit ready to be tested at CERN in January 2006
Final design for LHC
Prototype SPS 2004
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
19 September 2005
Layout around IP5
http://totem.web.cern.ch/Totem/
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
19 September 2005
http://totem.web.cern.ch/Totem/
Pot Design
• Brazing of the thin
window
• Two boxes ready at
the end of September
• Vacuum test
• Metallurgical test
0.5 mm
0.2 mm
Test Vacuum
Chamber for the pot
M.Oriunno, CERN PH-TOT
TOTEM Collaboration Meeting
19 September 2005
BPM Button
http://totem.web.cern.ch/Totem/
•Adapted design for TOTEM
•Price offer received from
CERAMTEC (in negotiation)
• Possibility to exploit CERN
technology
• Delivery in 10 weeks after the
contract signature
RF test bench
in production
in Prague
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
19 September 2005
Services
http://totem.web.cern.ch/Totem/
Enlarged pot size
Integration of a
new volume for
the services :
“Champignon”
concept
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
19 September 2005
Vacuum Design issues
http://totem.web.cern.ch/Totem/
1. The advantages for TOTEM of a compensation system interconnected
to the machine vacuum have been understood and studies (Vacuum
Physics calculations) are expected to confirm such a feature.
2. The fragility of the window during the bakeout phase has been argued
from FEM calculations -> The Roman Pot system will be designed to
be bakeable; extensive bakeout test to be done on the pot prototypes in
September. Alternatives: Full bakeout of the system or integration of a
temporary protective refrigeration system on the window.
3. Other points :
•
RP vacuum gauges read by the machine vacuum control
•
316LN for the BPM buttons (already ordered at CERN)
•
VacuumPraha is recognized as a firm able to supply system for
LHC applications (particular interest in their development of ion
pump)
•
Installation of RP is not on the critical path of the machine, more
details after the consolidation of the LHC planning
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
19 September 2005
RF Design issues
http://totem.web.cern.ch/Totem/
Detailed study done by M.Deile under the supervision of F.Caspers
• Measurements in the SPS test beam with H/E antennas
• Measurements in the lab with a network analyzer using a wirebeam
•Experience based on similar measurements done for other LHC
equipment
Conclusions (see Mario’s talk at the 6th RPTB
• Tightness of Roman Pot for e.m. fields:
E-field attenuation by the windows: ≥ 60 dB @ 40 MHz
B-field attenuation by the windows: 50 - 60 dB @ 40 MHz
• EMI in detector electronics still to be measured
• Beam coupling impedance of RP without ferrites: ≤ 1200 Ω
• Good improvement with ferrites (factor 1/5)
• Ferrite geometry to be optimized
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
19 September 2005
RP Station at 147 m
http://totem.web.cern.ch/Totem/
Additional
Sector valves
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
19 September 2005
Future plans
http://totem.web.cern.ch/Totem/
Pre-series of the vacuum chamber ready end of November :
Vacuum Characterization and measurement on the compensation system
Final test on the Full Pot prototype
Integration study on the detector assembly
Tunnel Integration & cabling
TOTEM Collaboration Meeting
M.Oriunno, CERN PH-TOT
19 September 2005