Date post: | 15-Jan-2016 |
Category: |
Documents |
Upload: | gilbert-jennings |
View: | 215 times |
Download: | 0 times |
HCAL-J Update (G.B. Franklin, CMU, Mar. 2015)
• 40 Ton Detector • 288 modules • Arranged in 4 sub-assemblies
24 M
odul
es (3
60 c
m)
12 Modules (180 cm)
1
Absorbers Scintillators
Wavelength Shifter
PMT
Rectangular to cylindricalLight Guide
Today’s Talk1) New Cosmic-Ray Timing Tests (Proto4)2) New light-guide details3) December engineering review4) Status of production
2
1) Cosmic Ray Timing MeasurementsFirst: A Brief Historical Note
Proto2 results shown at the Nov. DOE Review showed 340 ps timing resolution (cosmics)Predicted TOF better than 300 ps rms with improved light guides
3
Proto4 Cosmic Tests(Proto3 assembled and sent to JLab for Hall A tests)
Improved light guideMore than x2 photoelectrons
277 ps rms time resolution(after start-time resolution correction)
Vahe Mamyan’s measurements show we have exceeded our expected time resolution for cosmics
400 photo-electrons at peak
Integrated Raw FADC Units Time – Start Time (nsec)
4
Updated Monte Carlo Results
Vahe used Proto4 results to tune Monte Carlo
Result: 0.7 ns rms time resolution for 4.8 GeV/c neutrons(No change for 2.7 or 8.8 GeV/c simulations)
Simulated HCAL-J timing resolution for 4.8 GeV/c neutrons
5
2) Light Guide DetailsBracket and Optical Fiber Guide TubeMounting Holes Guide Tube Hole
Gluing Holes
Fishing Line Anchors
Laser-cut Acrylic Light Guide Bracket
Bracket Solvent-Welded to Cylinder
Bracket Bolted to End Cap
Guide Tube
Proto4 Back End Cap Detail
Guide Tube
Light Guide
AluminizedMylar
Bracket
6
3) December Engineering Review
• Review of Sub-Assembly concept and details of HCAL-J Module
to Subassembly connection
• Conceptual design document submitted by CMU
• Attended by:
• JLab: Mark Jones, Robin Wines, Whit Seay, Alan Gavalya
• CMU: Gregg Franklin, Vahe Mamyan, Alexa Johnson
• 2nd Day follow-up meeting discussed small design change in
HCAL-J front plate
• JLab will take over engineering of the support structures for
the 4 sub-assemblies this summer
7
4) Status of ProductionLight Guide Production
Laser Cutting90 seconds each
Bending JigRadiant Heater
Gluing JigSolvent Welding
Need to remember to take a photo of this
Diamond Fly-cutting
Oxy-hydrogenFlame Polishing
8
Light Guide Production Status
11 Completed and glued to WLS
30 more assembled- awaiting final milling and gluing WLS
Components for ~20 more in queue for gluing
Summary: Will soon have 50 completed light guides with many more parts already in queue for machining and bending
9
Production Status Summary• Proto3 and Proto4 could be considered first two modules
• Absorbers and scintillators ready for installation
• Purchased and received vacuum screws, plastic PMT adapters, etc.• VersaFab Machine Works producing 300 sheet-metal cans, 600 internal
shims, 1800 “ribs”• Will deliver 33% at a time• 2 weeks late on first shipment, but any day now…
• Awaiting delivery of custom-width aluminized Mylar• Activities At CMU
• 300 Steel Front End Plates and 300 Al. Back End Plates• All 600 have been cut to size• 40 each are being finalized (machined, drilled, tapped)
• ~ 50 Light guides and WLS ready• Expect to assemble~ 2 modules per day once cans are delivered• First shipment to JLab early summer (60 modules at a time)
• Must clear space as we assemble
10
Milestone Review
• Detailed design Completed: June 2014 (+ 2 months float)
DONE• Design review: (Sept. 2014) (+3 months float)
Scope to include sub-assembly concept. Dec. 2014DONE
• Module construction initiated: Oct 2014 (+4 months float)First two modules of finalized design under constructionLarge scale assembly awaits rib and shell order completionWill start Jan./Feb.NOW BEHIND (unless Proto3 and Proto4 counts or assembly of light guides counts)
• Module assembly 50% completed: March, 2015 (+4 months float)APPEARS THAT WE WILL BEAT THIS
• Construction completed: Sept. 2016 (+9 months float)