1. CRYSTAL COLLIMATION EXPERIMENT AT THE TEVATRON CSN1 LNF 17 September 2007 Walter Scandale CERN

2. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale2 OUTLINE Introduction Proposal for Experiment at Tevatron Tevatron Study Plan Contributions, Matching Efforts, LARP Support Summary

3. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale3 INRODUCTION Bent-crystal technique is well established for extraction of high energy hadron and heavy-ion beams from accelerators. Such an extraction was successfully demonstrated for up to 900 GeV beams at JINR, IHEP, CERN and Fermilab. Bend crystal channeling technique for beam halo collimation at high-energy considered for the SSC and the LHC since the early 90’s. A bent crystal, serving as a primary element, should coherently bend halo particles onto a secondary collimator. First successful measurements were performed at IHEP in 1998 for 1 to 70 GeV protons. Results of H8RD22 crucial to this respect (volume reflection efficiency up to 98 %). Test of a bent crystal into the Tevatron collimation system. First measurements (2005/06) quite encouraging.

4. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale4 Two-Stage Collimation with Target and Crystal Courtesy R. Assmann

5. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale5 PROPOSAL FOR EXPERIMENT AT TEVATRON Perform tests of crystal collimation at the tevatron, aiming at the highest-performance collimation in both the transverse planes. The results will be extrapolated to the LHC collimation system at full luminosity and beyond, A US-LARP Crystal Collimation Project has been proposed to conduct these studies in the time frame required by the LHC plans. An international collaboration is being organized to address the scientific issues

6. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale6 WHERE TO INSTALL CRYSTAL Target @ ~5  Collimator @~6  Scattered trajectories Install Crystal Collimator at E0 to replace a Tungsten Target and utilize the rest of the collimator 2 stage System. Proton Set 1 D49 Tar, E03 & F172 2nd Proton Set 2 D171Tar, D173 & A0 Pbar Set 1 F49 Tar, F48 & D172 Pbar Set 2 F173 Tar, F171 & E02

7. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale7 CRYSTAL COLLIMATOR SYSTEM E03 Secondary Collimator E0 Crystal Collimator Assembly E0 Scintillator Paddles PIN Diode BLM Laser – angular measurement crystal E03H 2 nd Collimator 14 mm channeled beam 31.542 m Pin Diode BLM to be extended for the purpose of the future experiment

8. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale8 TEVATRON MEASUREMENT GOALS 1.Channeled beam* 2.Volume-reflected beam* 3.Beam loss and radiation levels downstream of the crystal setup 4.Beam loss rate in the B0 (CDF beam-halo monitors) for 1- and 2- plane collimation 5.Possible deformation of the crystal or crystal holder during a vacuum baking process. 6.Attempt to study crystal damage: shock and integrated dose. (*) Add dedicated beam diagnostics Quantitative measure of collimation efficiency improvement is reduction of (3) – primary LHC concern – and (4). Simulate the deflected beam loss in the Tevatron and LHC (in collaboration with IHEP and CERN colleagues). Consistency with the current secondary collimator and absorber layout is of a concern here: need simulations and optimizations.

9. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale9 1.Demonstrate channeling with the existing strip crystal or with the ST4 crystal that was characterized in the September 2006 H8 experiment at CERN (by IHEP, CERN & INFN, arrived at Fermilab in March 07). 2.Confirm the 2005-2006 preliminary result that crystal channeling and volume reflections can improve the Tevatron collimation system efficiency. 3.Perform detailed simulations of collimation system performance with a single strip crystal in the realistic Tevatron lattice for both channeled and volume-reflected beams. 4.Work out a plan on beam diagnostics improvement and specify new goniometer for 2009 beam studies. TASKS-2007 (TeV study time: 1.5 shifts = 12 hrs)

10. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale10 1.Build improved beam diagnostics system and new goniometer. 2.Develop new strip and multistrip crystals. 3.Complete EOS and proton-only store angular scans with the crystal chosen in 2007. 4.Perform detailed simulations for a complete two-plane crystal-based Tevatron collimation system. 5.Try to perform tests to provide information about the possible deformation of the crystal or crystal holder during a vacuum baking process (up to 200 degrees). 6.Investigate a possibility for a crystal damage experiment where crystals and instrumentation for assessing dose rates could be placed in the Fermilab beams. Once enough beam is integrated on one crystal, it should be moved back to CERN for H8 beam line characterization. TASKS-2008 (TeV study time: 1.5 shifts = 12 hrs)

11. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale11 1.Install New Hardware:  Remove E01 collimator to replace with vertical crystal assembly  Crystal, goniometer, instrumentation tunnel installation 2.150-GeV Beam Tests (1.25 shifts):  Test BLM response, inchworm and channel the beam  Debug all motion control and instrumentation 3.980-GeV End-of-Store Beam Studies (4.75 shifts):  Find and characterize channeling (V-plane)  Collimate channeled beam (V, H)  Collimate volume-reflected beam (V, H)  Attempt full channeled collimation (V&H)  Attempt full volume-reflected collimation (V&H)  Repeat with another crystal type TASKS-2009 (TeV study time: 6 shifts = 48 hrs)

12. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale12 Demonstrate efficiency of a well-prepared bent crystal collimation system for 2 planes with channeled and volume-reflected 1-TeV beams at least for two crystal types (single and multi- layer) in comparison with tungsten target results. GOAL-2009

13. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale13 COLLABORATION CONTRIBUTIONS CERN: Experiments at H-8 beamline, manpower, beam characterization of “TeV” crystals to guarantee success at Tevatron INFN: manpower, crystal preparation, etching, mechanical and optical characterization, goniometer, roman-pots and trackers for the inspection of the deflected beams and for the measurement of the collimation efficiency. (? 350 keuro for ‘08 and 200 keuro for ‘09 ?) IHEP: manpower, crystal preparation, etching, characterization; simulations, new crystal technologies PNPI, JINR: manpower, theory, simulations, beam diagnostics, DAQ, new crystal technologies KEK: manpower, beam diagnostics Fermilab*: crystal and other hardware implementation in the Tevatron, EOS beam time, beam diagnostics, DAQ, simulations, deformation/damage tests SLAC*, BNL*: manpower, beam diagnostics, deformation and damage tests (*) As a part of the LARP project

14. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale14 DELIVERABLES 1. Conclusive data and directly relevant input for decisions on a possible upgrade path for LHC collimation: improved collimation efficiency and reduced irradiation of downstream components in a quantitative agreement with corresponding calculations, and quantitative answers to the questions on damage limits and sensitivity analyses. 2. Crystal technology, process (channeling or volume reflection), hardware (goniometer etc.) & instrumentation most suitable for 2-plane collimation of LHC beams, transferred to CERN.

15. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale15 LARP SUPPORT This proposal was presented to the LARP Collaboration meeting in April 2007 and at the FNAL Accelerator Advisory Committee in August 2007. It was very welcomed at the two meetings. It was noted that the timing is right and critical (next year start would be too late). The proposal was supported by the LARP Accelerator System management, DOE Review and approved by the LARP Executive Committee. The FY08 budget request is $0.22M, while for FY09 it is $0.13M.

16. CSN1, Sept. 17, 2007Crystal Collimation Experiment - W.Scandale16 SUMMARY Demonstration of crystal-based collimation by utilizing unique possibilities provided at the Tevatron at the end of the experimental collider run opens doors to: Possible upgrade path for the LHC collimation system:  enhanced performance  reduced impedance  heavy-ion beam halo cleaning Possible complementary collimation systems:  Fermilab Recycler in Project X  ILC Beam Delivery System  Muon Collider With all of the above, we are now seeking for the INFN CSN1 support of this proposal.