# Presentation: 246660

## Review of the T980 Crystal Collimator Installation

-  **Presentations:**
-  Nikolai Mokhov, Intro (status, goals, timescale, impact on 	D0 & CDF)
-  Rob Reilley, Goniometer modifications & improvements
-  Dean Still, Installation, commissioning & early study plans
-  Rick Tesarek, New E0 instrumentation
-  Jim Zagel, Flying wires

**August 7, 2008**
**Committee Members:**
- Roger Dixon (chair), Bruce Hannah, Ron Lipton, and Phil Schlabach

## Goals for 2008 to Spring 2009 (Phase I)

- Measure channeled, volume-reflected (?) and scattered beams as well as beam losses downstream of the crystal setup in comparison with simulations.
- Demonstrate reproducible beam loss reduction in the B0 and D0 in comparison with simulations, **aiming at a routine use of the crystal based collimation in the Tevatron stores.**

- Two phases as described in the T980 MoU

**Phase I Goals**

## STRUCT/CATCH Simulations: Profiles at 9 CriticalLocations in Tevatron with O-Shaped Crystal 

- E03 collimator

- E11 flying wire

- A. Drozhdin

- First turn, all collimators are retracted

## Multi-Turn Simulations with 0.44-mrad O-shaped Crystal

- All collimators are in working positions

- A. Drozhdin

- Total losses on E03 and F172 via channeling, VR and MCS.
- Inversely proportional to Dean’s LE033 BLM with E03 out

- Channeled beam loss on E03

- Edge-scattered in E03 and F172, x 5

- Loss at B0, x 140

## Plans for Phase I

- Installation at appropriate downtime or October mini-shutdown (10-12 hrs).
- Commissioning: pre-beam and beam tests and End-of-Store studies (see Dean’s talk).
- Several EOS studies of beam dynamics and collimation efficiency aiming at reproducibility and BOS test.
- Routine use of crystals in the Tevatron stores.
- Preparation of new crystals, hardware and electronics for installation in the tunnel during the Spring 2009 shutdown.
- Further plans, scope and beam requests depend on outcome of Phase I and are subject to a FNAL review and 2009-2010 run plans.

## Crystal Installation

_**Current Status of Crystal Assembly:**_
- All mechanical modifications  to the crystal assembly have been completed.
- All motion control and instrumentation has been tested under vacuum- laser as well.
- Crystal assembly has been vacuum certified and pre-baked ready for installation.
_**Installation Involves:**_ 		(Tev Mechanical and survey group)
- Stage equipment in the tunnel: 				2 hours Vent with N2, unbolt 2 flanges and remove spool: 		.5 hours Install Crystal: 					1 hour Make up flanges loose with copper seal: 			.5 hours Survey: 						2-4 hours Final torque 2 flanges: 					.5 hours Pump down and rough leak check: 				2 hours Turn on Ion Pump and final leak check:			 2 hours Remove equipment from tunnel: 				1 hour
- Verify operation crystal Hor, & Ang. motion control & instrumentation.	(A. Legan)
- Install & verify operation of laser. 				(T. Johnson)
-                                                                			 **Total ****	****10 – 12 hours**
**This procedure has been successfully completed  3 times before in ~ 10 hours.**
**Crystal will be installed at earliest appropriate downtime or Oct short shutdown.**

**Hopefully tomorrow morning!**

## Crystal Commissioning

## Review of the T980 Crystal Collimator Installation

**The Committee recommended that installation and commissioning of the crystal and its associated hardware for T980 be allowed.**

## Other News

-  A half-a-day crystal collimation workshop on October 29, 2008, adjacent to the LARP CM11, organized by R. Noble and myself.
-  A crystal collimation workshop at CERN next Spring.
-  S. Peggs and myself are working on T980 and CRYSTAL plans and budget for the end of FY08 and for FY09.
-  A T980 meeting will take place September 3 or 4 to discuss installation, early beam tests and physics goals and plans for Phase II, after Spring 2009 shutdown.