Status of the Roman Pot Project reminder prototyping & testbeam mechanics & infrastructure

1. Status of the Roman Pot Project • reminder • prototyping & testbeam • mechanics & infrastructure • simulation Hasko Stenzel ATLAS week October 2006

2. Roman Pots for ATLAS RP RP RP RP 240m 240m IP RP RP RP RP MAPMTs FE electronics & shield PMT baseplate optical connectors scintillating fibre detectors glued on ceramic supports 10 U/V planes overlap&trigger Roman Pot Unit Roman Pot H.Stenzel, October 2006

3. testbeam: October 3-18 Purpose: Verify detector performance observed in 2005 at DESY (6 GeV e- ) with new(larger) detectors, new ATLAS-type electronics with a high energy beam. New prototypes: • 10 planes, U&V, 16 fibres  tracking • 2 planes, U&V, 64 fibres  final geometry • 2 overlap detectors, 120 fibres each  alignment • trigger scintillator  elastic L1 Program: • hit multiplicity & efficiency • cross talk • spatial resolution & homogeneity • edge sensitivity & active surface • alignment performance with overlap detectors • trigger efficiency & uniformity H.Stenzel, October 2006

4. detector prototypes for testbeam 2006 2 x 2 x 30 overlaps 2 x 2 x 64 construction studies 10 x 2 x 16 resolution studies • Fabrication of prototypes at cern bt PH/DT2 • with support from Lisbon (LIP) for • fibre machining, aluminum coating, QC • testbeam mechanics • and from Giessen for • gluing of fibres • optical connectors H.Stenzel, October 2006

5. QC: Metrology Fibre ends of 10_2_16 after machining at 45º < 20µm variation from one plate to another prototype 2005: > 250 µm variation H.Stenzel, October 2006

6. overlap detector: new technology Section to be bent Straight section Preheat from room temp to 85ºC Bend fibres at 85ºC A. Mapelli H.Stenzel, October 2006

7. trigger scintillator New design of trigger scintillator with lightguide coupled to a PMT. photomultiplier light guide scintillator H.Stenzel, October 2006

8. electronics: final set-up fibreMAPMTPMF(MAROC)MotherBoardDAQ H.Stenzel, October 2006

9. electronics: testbeam set-up CERN, Orsay (MAROC) & Lund (PMF & MB) PMF Build Up for testbeam October R/O FPGA R/O FPGA Active board MAROC R/O chip MAROC chip Adapter board HV board H.Stenzel, October 2006

10. The final ATLAS Roman Pot Unit • Pre-production of one unit at Vakuum Praha • expected at CERN Oct.31 • will be instrumented and tested • review of the tests before production • possible timescale : 4 units at CERN April-May 2007 H.Stenzel, October 2006

11. Pre-production unit Courtesy of Vakuum Praha H.Stenzel, October 2006

12. The final Roman Pot Pumping hole Top flange with helicoflex joint Brazing under test S.Mathot (TS-MME) Rectangular body out of center Overlap extrusions brazed on bottom • Prototyping & production at CERN TS • Material for prototype & final production arrived Oct.2 • Prototyping Oct/Nov 2006 • final production sync. with Unit procurement H.Stenzel, October 2006

13. Infrastructure: Cable installation Reminder – cabling list: H.Stenzel, October 2006

14. Infrastructure: Cable installation Installation of all cables through UPS galleries is now completed on both sides of IP1 • Access to the UPS galleries is not allowed anymore due to the installation and calibration of the instruments for the geometers. • HV multiconductor cables are to be installed, different path via US to UX, depending on the location of HV power supplies (US15) Air-core cables – min. bending radius of 250mm respected Optical fibers H.Stenzel, October 2006

15. Q4 polarity switch RR13 Level 1 inverter 7kA Switch for Q4 quadrupole to change its polarity when switching from normal to ATLAS/Lumi optics. Base & cabling are completed. Temporary Cu plates ordered, will be installed soon Buying the switch itself can be done later RQ4.L1B2 RQ4.L1B1 RR13 Level 0 DFBLA Christophe Coupat AB/PO H.Stenzel, October 2006

16. Simulation of the LHC set-up elastic generator PYTHIA6.4 with coulomb- and ρ-term SD+DD non-elastic background, no DPE beam properties at IP1 size of the beam spot σx,y beam divergence σ’x,y momentum dispersion ALFA simulation track reconstruction t-spectrum luminosity determination later: GEANT4 simulation beam transport MadX tracking IP1RP high β* optics V6.5 including apertures H.Stenzel, October 2006

17. Simulation of elastic scattering hit pattern for 10 M elastic events simulated with PYTHIA + MADX for the beam transport t reconstruction: • special optics • parallel-to-point focusing • high β* H.Stenzel, October 2006

18. acceptance distance of closest approach to the beam Global acceptance = 67% at yd=1.5 mm, including losses in the LHC aperture. Require tracks 2(R)+2(L) RP’s. Detectors have to be operated as close as possible to the beam in order to reach the coulomb region! -t=6·10-4 GeV2 decoupling of L and σTOT only via EM amplitude! H.Stenzel, October 2006

19. t-resolution The t-resolution is dominated by the divergence of the incoming beams. σ’=0.23 µrad ideal case real world H.Stenzel, October 2006

20. L from a fit to the t-spectrum Simulating 10 M events, running 100 hrs fit range 0.00055-0.055 large stat.correlation between L and other parameters H.Stenzel, October 2006

21. experimental systematic uncertainties • Currently being evaluated • beam divergence • detector resolution • acceptance • alignment • beam optics • ΔL/L ≈ 1.9-2.1 % • missing: background studies • (are under way) • total error ≈ 2.6-2.8 % H.Stenzel, October 2006

22. conclusion • testbeam 2006 is starting, preparations in full swing • new prototypes produced, including overlaps and trigger • electronics set-up close to ATLAS • RP units and pot prototypes are under production • major cable installation effort • progress on simulations for TDR H.Stenzel, October 2006