Fermilab Accelerator Physics Center US LARP T 980

Fermilab Accelerator Physics Center US LARP T 980 and UA 9 Crystal Collimation Nikolai Mokhov DOE LARP Review Fermilab June 1, 2011

OUTLINE Ø Crystal Collimation for LHC Ø T-980 Layout Crystals, Data Analysis Ø Pixel Detectors Ø T-980 Special Run May 16 -26 Ø UA 9 Status and Plans DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 2

Crystal Collimation for LHC Drive beam halo deeper into a secondary collimator (coherently) Reduced secondary and tertiary halo Two prove-of-principal experiments supported by LARP: T-980 (Tevatron) and UA 9 (SPS) DOE LARP Review - Fermilab, June 1, 2011 Reduced beam losses at critical locations: detectors at IRs and superconducting magnets downstream Crystal Collimation - N. V. Mokhov 3

T-980 Mission v Develop a collimation system for hadron colliders based on bent crystal techniques, which has a promise to reduce machine impedance, beam losses in superconducting magnets, improve background conditions in the collider detectors and be compatible with heavy-ion operation. v Start routine use of crystal collimation in the entire Tevatron collider store. v Study the system’s performance and underlying beam dynamics exploiting the unique possibility provided by the Tevatron collider to evaluate an engineering implementation of this technique in the LHC. DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 4

Current T-980 Layout at E 0 § Goniometer moves and rotates a crystal to a precise (~2 mrad) angle § Crystal inserted at 5 s § Collimators inserted at (6 -7)s to intercept CH and VR particles § Loss monitoring system: PIN diode, BLM, Scintillating paddles § 2 -plane pixel telescope to see CH and VR beam profiles on E 03 DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 5

New Ferrara Crystal MS-16 F 2 (1) θVR Replaced damaged MS-16 F 1 in vertical goniometer in March 2011 θVR DOE LARP Review - Fermilab, June 1, 2011 • Total number of strips: 16 • Interferometric characterizations: 13 strips are aligned within 80 μrad. • Length of each strip along the beam: 1 mm • Transversal thickness of each strip: 0. 3 mm • Anticlastic curvature radius : 4. 0 m • Max baking temperature: 100 °C • Miscut angle: 80 μrad • Crystal and holder do not require cleaning Crystal Collimation - N. V. Mokhov 6

Ferrara Crystal MS-16 F 2 (2) E. Bagli V. Guidi A. Mazzolari (2011) Predictions for Tevatron: a = 72. 3 mrad, e = 94. 8% DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 7

MS-08 -09 Angle Scan: Excellent Performance March 2010 May 2011 DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 8

Good Performance and Issues with O-shaped Bending angle declared to be 360 mrad. In reality it is always less. ~ 230 mrad Explanation Measured displacement = 5. 5 mm (220 mrad) instead of expected 8. 5 mm (360 mrad) DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 9

ORIGIN-based Data Analysis Same for VR Crystal orientation (urad) CH peak position CH acceptance VR acceptance DOE LARP Review - Fermilab, June 1, 2011 Losses (Hz) CH peak exact position CH acceptance CH efficiency!!! Collimator position (mm) Viktoriya Zvoda Crystal Collimation - N. V. Mokhov 10

Results for T-980 Crystals Bend angle/VR angle, urad Size along the beam, mm Miscut angle, urad PNPI 410/9 5 1600 -10/0. 43 25. 55/-1. 13 75 (CH) PNPI 360/16 5 120 -8. 13/0. 39 22. 44/-1. 06 60 (CH) 70 (VR) CH Name of the plane, Origin crystal deflectio n type O-BNL-02 O-05 -09 (110), hor Displacement of of particles at F 172 E 03 (CH/VR), mm, simulated MS-08 -09 (111), vert IHEP 200 and 8/strip 0. 9 small 5. 04/-1. 56 -6. 58/2. 07 MS-16 -11 (110), vert INFN 250 and 13. 5/strip 1/strip 600 6. 3/-5. 36 -8. 23/7. 11 QM-01 -10 (111), vert PNPI 120/15 2 50 2. 9/-0. 37 -3. 95/0. 49 DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov Maximum Efficiency, % 11

Pixel Telescope • Tracking deflected particles • Currently installed in front of E 03 collimator • Has 3 telescoping planes (V and H), currently some problem with two • Supported by Ethernet Networking • Multi-chip modules are of CMS forward pixel production • 1 x 2 cm 2 with a sensitive area 0. 8 x 1. 6 cm 2. • Pixel size 100 x 150 mm 2, resolution 7 -8 mm. DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 12

Special Tevatron Run May 16 -26 • Four 6 -hour dedicated End-of-Store (EOS) T-980 periods, with a great help from visitors from CERN and INFN. • Studied three crystals and pixel detector: a lot of interesting data to analyze! • Issues with MS-16 because of its length and motion of goniometer. Possible to have a work around and would like to try again. • Issues with several pixel detector planes to be fixed. • 2 -plane studies are incomplete, would like to try again. DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 13

First Image on Pixel Detector Wednesday, May 25, 2011 Pixel detector to assist beam collimation experiments For the first time, on Wednesday, May 18, physicists operated a tiny detector in the Tevatron that will help develop a technology to improve the quality of collision data. …. . Members of the crystal collimation study, a joint program of Fermilab's Accelerator Division, the Accelerator Physics Center, and the LARP program, celebrated their success with the pixel detector at the Tevatron in the Main Control Room on Wednesday, May 18 (lower left). DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 14

Channeled beam from O-05 -09 crystal as angle is changed from AM to CH to VR DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 15

Good Tool for Analyzing Channeled Beam DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 16

T-980 Summary • T-980 gained good experience in testing various bent crystal types. Estimated channeling efficiency of Oshaped crystals is 65 -75%, volume reflection efficiency of 8 -strip crystal is 70%. Small opening in quasi-mosaic crystal holder made it difficult to work with in the collider. T-980 favors multi-strip (large angular acceptance, MVR gives large deflection) and O-shaped crystals. Both - easy to work with. • Enhanced instrumentation from scintillating paddles to pixel telescope is able to provide comprehensive info. • Successful studies at Tevatron May 16 -26: dedicated long periods of EOS. More EOS will be requested before the end of the Tevatron Run II. DOE LARP Review - Fermilab, June 1, 2011 Crystal Collimation - N. V. Mokhov 17