# Presentation: 128338

## The DØ UpgradeCentral Fiber Tracker

**Project Leaders:**
**Alan Bross (FNAL)**
**Mitch Wayne (Notre Dame)**

## Outline

**Introduction and Overview**
**	****Physics and performance goals**
**	****Brief detector description**
**Recent progress**
**	****Technical progress - fibers, VLPC, cryo, ...**
**	****Increases  in manpower**
**Cost and Schedule**
**	****Cost drivers**
**	****Miilestones**
**Project organization**
**	****Organization chart**
**	****Institutions**
**Summary**

## Physics Goals &Design Features

**The CFT is an integral part of the**
**DØ upgrade. Physics goals of the**
**upgrade include**
**High precision measurements of m****t****,m****W**
**Search for the Higgs boson**
**Search for physics beyond SM **
**Features of the CFT include:**
**Seamless tracking to ****η**** = 1.7**
**1st-level electron and muon triggering**
**With silicon, tagging of b-quarks**
**Improved momentum measurement**
**Charge determination for e and ****μ**

## Central Fiber Tracker

**77k channels**
**Radial coverage: 20 - 50 cm**
**Full coverage to eta = 1.7**
**SciFi: 1.6-2.5 m, Clear: 8-11 m**
**xu-xv doublet layer structure**
**VLPC readout**

## Fiber

**All scintillating and clear fiber has been ordered from Kuraray (Japan)**
**	****xx meters of 835 micron diameter scintillating fiber**
**	****yy meters of 960 micron diameter clear fiber**
**Delivery schedule**
**	****SciFi: ?/?/97 - ?/?/?**
**	****Clear: ?/?/97 - ?/?/?**

## VLPC Rate Studies

**Test enables the**
**measurement of **
**VLPC:**
**Gain**
**Relative QE**
**Relative eff.**
**as a function of**
**photoelectron **
**background rate**

## HISTEVI Characterization

**~**** 300 arrays of  HISTEVI VLPC characterized**
**Performance measured as a function of :**
**Bias voltage**
**Operating temperature**
**Background rate**
**Yield of good arrays measured for  comparison with**
**Boeing yield model**
**	**

## HISTEVI Characterization

**Efficiency calculated from Poisson**
**statistics:**
**Mean = 9 pe * relative QE**
**Threshold = N****pe**** for 0.5 % dark count**
**Efficiency is probability of a Poisson**
**distribution with this Mean > Threshold**

## HISTEVI Yield

**Characterization Yield Results**
**Arrays measured: ****	****	****296**
**1 pixel latched:****	****	****12**
**device breakdown:****	****2**
**1 pixel open trace:****	****60***
**failed efficiency cut:****	****2**
**Good array total: ****	****	****220 (74%)**
*** open trace problem solved****	****	**

## HISTEVI VLPC

**Final Yield Results**
**	****	****	****	**
**	****	****	****	****       **_**Proposed**_**	****          **_**Actual**_
**Material Quality****	****	****.82****	****	****1.0**
**Silicon Epi Handling****	****	****.98****	****	****1.0**
**Array Processing****	****	****.95****	****	****.95**
**Wafer Quality****	****	****	****.75****	****	****1.0**
**Dicing****	****	****	****	****.98****	****	****1.0**
**Hybrid Assembly****	****	****.98****	****	****.98**
**Visual Screen****	****	****	****.75****	****	****.98**
**Hybrid Screen Test****	****	****.70****	****	****.68 ****(.95)**
**	****	****	****	****	**
**TOTAL****	****	****	****	****.27****	****	****.61 ****(.85)**
**Boeing now proposing:**
**“****Fixed cost per part to specification”****	**

## VLPC Cassette

_**1024**_** Channel**
**VLPC Cassette**
_**128**_** channel **
**modularity**
**Design complete**
**Prototype in fabrication**

## VLPC Cryo

**Mini- cryostat for 128 channel **
**VLPC module -  provides detailed**
**thermal mapping**
**Fabrication is complete**
**Ready for test**

## VLPC Cryo

**4-Cassette Cryostat**
**Holds 4, full-size VLPC cassettes **
**Provides input to final cryo design**
**Fabrication is complete**
**Final testing, safety review underway**

## VLPC Cryo

**Global Cryogenics System**
**Recent increase in manpower**
**excellent progress**
**Refrigerator in place at DAB**
**Large part of He distribution in place**
**Test run expected mid-April**

## Mechanical Design

**Key mechanical elements **
**under design include:**
**Overall support structure**
**Support cylinders**
**Fiber ribbon fabrication**
**Fiber ribbon mounting**
**Integration and alignment**
**Design driven by requirement of**
**~ 50 micron precision on each **
**fiber’s location**

## Mechanical Design

**Support Cylinders**
**Tradeoff:**
**Roundness & rigidity  vs  Material Budget**
**Cylinder thickness & material issues now well understood**
**Two options: build at FNAL or purchase from outside*******
**Prototype cylinder out for bid**
*** ****	****At least one company appears interested and**
**	****capable**
**	****	**

## Mechanical Design

**Fiber Ribbons**
**Curved ribbons are desirable for  **
**mounting, but curved molds are difficult **
**and expensive to fabricate**
_**Proposed technique:**_
**Make straight, flexible plastic molds**
**Insert into a rigid, curved backing**
**Preliminary tests on 100” lengths of **
**polystyrene are encouraging. Two **
**machines at FNAL likely capable of**
**producing flexible molds**
**	**

## Mechanical Design

**Full Mechanical Prototype**
**Plan in place to fabricate prototype**
**cylinder to final specifications:**
**Start building ribbons by ****3/23**
**Cylinder fabrication begins ****4/1**
**Ribbon-laying machine completed ****4/20**
**Practice ribbon laying: ****4/1 - 7/31**
**Ribbon laying on final cylinder begins on ****8/4**
**Test with cosmic rays begins ****10/4 **

## Calibration

**New technique using blue light **
**through fiber ****cladding**
**Fast blue LEDs readily available**
**Fiber optic panel for light distribution, samples from two vendors test o.k.**

## Calibration

**New technique using blue light **
**through fiber ****cladding**
**Fast blue LEDs readily available**
**Fiber optic panel for light distribution, samples from two vendors test o.k.**

## CFT Electronics

**Schematic of CFT readout and trigger chain**
**SIFT chip for trigger pickoff**
**Design complete**
**Chip run successfuly at 90 nsec**

## CFT Costing

**M&S Total and Contingency**
**Level 4 Tasks**

## CFT Costing

**Major Cost Drivers**
**SciFi, clear fiber: $1.58 M**
**	****	****Fiber ordered from Kuraray**
**	****	****Delivery to FNAL: 3/97 - ??**
**VLPC: $6.25 M**
**	****	****33% improvement in yield **
**	****	****Contract being negotiated**

## Manpower

**Estimated manpower required to **
**complete CFT project**

## CFT Manpower

**Substantial increase in **
**manpower since last review**
**5 Technicians:**
**	****David Butler, Jim Fagan, Mike McKenna,**
**	****Jim Seeman, Ted Gasteyer**
**3 Engineers:**
**	****Ang Lee,  John Krider,  MayLing Wong**
**3 Physicists:**
**	****Eric Flattum, Gaston Gutierrez, **
**	****Marcel DeMarteau**

## Milestones

**CFT Milestones**
**Fiber order placed****	****	****	****Sept 96**
**Notice to proceed on HISTEVI****	****Mar 97**
**1st article  cassette ready to test****	****May 97**
**Engineering design complete****	****June 97**
**Cylinder fabrication begins****	****	****July 97**
**Cassette module prod. begins****	****Dec 97**
**Ribbon fabrication begins****	****	****Dec 97**
**Waveguide production begins****	****Jan 98**
**Ribbon mounting begins****	****	****Mar 98**
**Cassette assembly begins****	****	****Apr 98**
**VLPC production complete****	****	****June 98**
**Cryo system operational****	****	****June 98**
**Tracker assembly begins****	****	****Aug 98**
**Cassette assembly complete****	****Apr 99**
**Tracker assembly complete****	****July 99**

## Milestones

**VLPC/Cassette Milestones**
**Notice to proceed on HisteVI****	****Mar 97**
**1st article cassette ready to test****	****May 97**
**Begin 1st cryostat fabrication****	****Jun 97**
**VLPC prodution 50% complete****	****Aug 97**
**Cassette production readiness    ****	****Sep 97**
**	****review**
**Module production begins****	****	****Dec 97**
**Cassette Assembly begins****	****	****Apr 98**
**Cryo system operational****	****	****Jun 98**
**VLPC production complete****	****	****Jun 98**
**Cassette assembly 50% complete ****	****Oct 98**
**Cassette assembly complete****	****Apr 99**

## Milestones

**CFT Fabrication Milestones**
**Engineering design complete****	****Jun 97**
**Connector design complete****	****Jun 97**
**Fiber ribbon design complete****	****Jul 97**
**Ribbon mounting procedure****	****Jul 97**
**	****finalized**
**Cylinder design complete****	****	****Jul 97**
**Support system design complete****	****Sep 97**
**Ribbon fabrication begins****	****	****Dec 97**
**Waveguide fabrication begins****	****Jan 98**
**Ribbon mounting begins****	****	****Mar 98**
**Tracker assembly begins****	****	****Aug 98**
**Ribbon fabrication ends****	****	****Jan 99**
**Ribbon mounting complete****	****	****Apr 99**
**Waveguide production ends****	****Jul 99**
**Tracker assembly complete****	****Jul 99**

## Organization

**Central Fiber Tracker**

## Organization

**List of CFT Institutions**
_**Institution**_**	****	****	****	**_**Contact**_
**Fermilab****	****	****	****	****Alan Bross**
**University of Illinois (Chicago)****	****	****Mark Adams**
**Korea University****	****	****	****	****??**
**Kyungsung University****	****	****	****??**
**University of Notre Dame****	****	****	****Mitch Wayne**
**Purdue University****	****	****	****David Koltick**
**Rice University****	****	****	****	****David Adams**
**University of Rochester****	****	****	****Tom Ferbel**
**Seoul National University****	****	****??**

## Summary

**All fiber for the CFT on order**
**VLPC well understood, yield for HisteVI better than expected**
**Recent increase in technical manpower leading to good progress in mechanical design**
**Athough several engineering and design issues need to be resolved, there are no “show stoppers”.  We expect to deliver the tracker on schedule and on budget, ready to help DØ take full advantage of the physics opportunities available with the Main Injector.**