Difference between revisions of "GlueX Start Counter Meeting, April 19, 2012"

From GlueXWiki
Jump to: navigation, search
(copy of last time)
 
m (Text replacement - "www/halldweb1/" to "www/halldweb/")
 
(9 intermediate revisions by the same user not shown)
Line 1: Line 1:
 
GlueX Start Counter Meeting<br>
 
GlueX Start Counter Meeting<br>
−
Thursday, April 5, 2012<br>
+
Thursday, April 19, 2012<br>
 
10 am EDT<br>
 
10 am EDT<br>
 
JLab: CEBAF Center, Room 326/327<br>
 
JLab: CEBAF Center, Room 326/327<br>
Line 7: Line 7:
  
 
# Announcements
 
# Announcements
−
## Mark Ito submitted PR for SiPM's:
+
# Review [[GlueX Start Counter Meeting, April 5, 2012#Minutes|minutes from previous meeting]]
−
##* 3X3 mm, 100 micron pixels, 10 pieces
+
# Prototype Report
−
##* 3X3 mm, 50 micron pixels, 10 pieces
+
# Readout Design  
−
# Review [[GlueX Start Counter Meeting, March 22, 2012#Minutes|minutes from previous meeting]]
+
# Contract Status
−
# Prototype Report: FIU team
+
# Simulation
−
# Readout Design: Tim, Chuck, Fernando
+
−
# Contract Status: Werner
+
−
# Simulation: Puneet
+
−
 
+
−
== Minutes ==
+
−
Present:
+
−
* '''FIU''':  Puneet Khetarpal, Eric Pooser
+
−
* '''Jlab''':  Eugene Chudakov, Chuck Hutton, Beni Zihlmann(chair)
+
−
 
+
−
# Juri (Hall-B), Marc Ito and Chuck Hutton did meet to discus Hall-B start counter design.
+
−
# FIU was not able to get into contact with machinist from McNeal who polishes the scintillator.
+
−
# Chuck showed [https://halldweb1.jlab.org/talks/2012-2Q/sc_4_05_12.pptx current design] status of the start counter drawings. The following questions were raised:
+
−
## Hall-B uses MV2000 to wrap the scintillators. How do they do that?
+
−
## Why using an outer foam shell? Could this be dropped in the installation? Maybe only use it for transport or handling? Maybe only have some kind of tape on the outside for holding the structure together?
+
−
## Could the inner foam shell in the down stream nose but reduced to half the length or even less? Only have foam during construction but remove some of the nose when installing it?
+
  
 
=Communication Information=
 
=Communication Information=
Line 34: Line 19:
 
* ESNet: 8542553
 
* ESNet: 8542553
 
* [http://evo.caltech.edu/ EVO]:
 
* [http://evo.caltech.edu/ EVO]:
−
** Meeting URL: http://evo.caltech.edu/evoNext/koala.jnlp?meeting=e9eIeivevnaeaBIsaaI9 <!--good through April 5-->
+
** Meeting URL: http://evo.caltech.edu/evoNext/koala.jnlp?meeting=eneueMvsv2aBaDInalIn <!--good through March 21, 2013-->
−
** Phone Bridge ID: 11 7685
+
** Phone Bridge ID: 13 2615
  
 
==Slides==
 
==Slides==
  
−
Talks can be deposited in the directory <code>/group/halld/www/halldweb1/html/talks/2012-2Q</code> on the JLab CUE. This directory is accessible from the web at https://halldweb1.jlab.org/talks/2012-2Q/ .
+
Talks can be deposited in the directory <code>/group/halld/www/halldweb/html/talks/2012-2Q</code> on the JLab CUE. This directory is accessible from the web at https://halldweb.jlab.org/talks/2012-2Q/ .
 +
 
 +
=Minutes=
 +
 
 +
Present:
 +
* '''FIU''': Werner Boeglin
 +
* '''JLab''': Eugene Chudakov, Mark Ito (chair), Simon Taylor, Beni Zihlmann
 +
 
 +
==More on the Hall B Start Counter==
 +
 
 +
Mark made a few more remarks about things the Youri Sharabian told us:
 +
 
 +
* When machining from a block of scintillator there will internal stresses. It may have to be done as a two-step process if this is attempted.
 +
* Polishing is challenging. There was no hand polishing for the Hall B start counter.
 +
** Molded surfaces have the best quality, better than if hand polished.
 +
* Cutting the scintillator too fast can lead to crazing. Likewise trying to cut too much at a time.
 +
* Wrapping the counters was difficult. Started with thermally shaped Tedlar material.
 +
* Rohacell does not come in large blocks so inner form support used Plastifoam[?] machined out of a single piece, to about 1/4″ thick
 +
* The outside foam was made of individual pieces, from a softer foam than the inner foam. Woven cotton tape was wrapped around the outside to secure everything.
 +
 
 +
==Prototype News==
 +
 
 +
McNeal promises to send their first sample today or tomorrow. They bend the scintillator first and then machine the edges.
 +
 
 +
E&F Plastics had proposed to machine a the whole counter from a single piece of scintillator. Samples were sent to them, but no word on any progress. If McNeal does produce a satisfactory sample, Werner may go back to this company.
 +
 
 +
When the sample for McNeal arrives it will be tested like previous samples.
 +
 
 +
Eugene asked if we have the final dimensions for the counters. Werner replied yes, to within 5 to 10%. The geometry is driven by largely by the size and placement of the SiPM's on the read-out board.
 +
 
 +
==Read-out design==
 +
 
 +
Fernando is finishing work on the BCAL read-out for the beam test. He will turn to work on the start counter soon.
 +
 
 +
==Contract status==
 +
 
 +
We discussed whether we should get started on this work with the design in its current state, with some questions unanswered. Eugene thought that we should aim for award of the contract at the beginning of the next fiscal year which means we have to start getting the paperwork moving now. Mark will send Werner a first draft of the documents to get started.
 +
 
 +
==Simulation==
 +
 
 +
Simon asked about the current HDDS geometry. The change from 40 counters to 30 counters has not been put in yet. Same for the new radial placement. Werner agreed to look into this.
 +
 
 +
==Technical Design Report==
 +
 
 +
Werner agreed to look at the start counter section.
 +
 
 +
==Calibration and Alignment==
 +
 
 +
Mark raised the issue of developing a conceptual design of how this should be done. This involves
 +
* identifying quantities to be calibrated
 +
* calling out data that needs to be taken, both the type and the amount
 +
* sketching the analysis procedure
 +
* noting dependencies on other detector systems
 +
We will schedule a discussion for a future meeting.
 +
 
 +
Werner mentioned that he has had a plan to look into feeding LED test signals into the counters somehow. This is largely a mechanical problem.
 +
 
 +
==Action Items==
 +
 
 +
* Get sample from McNeal and test it. -> FIU team
 +
* Write rough draft of contract documents and send to Werner. -> Mark
 +
* Bring geometry in HDDS up-to-date. -> Werner
 +
* Look at start counter section in the TDR. -> Werner

Latest revision as of 22:50, 31 March 2015

GlueX Start Counter Meeting
Thursday, April 19, 2012
10 am EDT
JLab: CEBAF Center, Room 326/327

Agenda

  1. Announcements
  2. Review minutes from previous meeting
  3. Prototype Report
  4. Readout Design
  5. Contract Status
  6. Simulation

Communication Information

Video Conferencing

Slides

Talks can be deposited in the directory /group/halld/www/halldweb/html/talks/2012-2Q on the JLab CUE. This directory is accessible from the web at https://halldweb.jlab.org/talks/2012-2Q/ .

Minutes

Present:

  • FIU: Werner Boeglin
  • JLab: Eugene Chudakov, Mark Ito (chair), Simon Taylor, Beni Zihlmann

More on the Hall B Start Counter

Mark made a few more remarks about things the Youri Sharabian told us:

  • When machining from a block of scintillator there will internal stresses. It may have to be done as a two-step process if this is attempted.
  • Polishing is challenging. There was no hand polishing for the Hall B start counter.
    • Molded surfaces have the best quality, better than if hand polished.
  • Cutting the scintillator too fast can lead to crazing. Likewise trying to cut too much at a time.
  • Wrapping the counters was difficult. Started with thermally shaped Tedlar material.
  • Rohacell does not come in large blocks so inner form support used Plastifoam[?] machined out of a single piece, to about 1/4″ thick
  • The outside foam was made of individual pieces, from a softer foam than the inner foam. Woven cotton tape was wrapped around the outside to secure everything.

Prototype News

McNeal promises to send their first sample today or tomorrow. They bend the scintillator first and then machine the edges.

E&F Plastics had proposed to machine a the whole counter from a single piece of scintillator. Samples were sent to them, but no word on any progress. If McNeal does produce a satisfactory sample, Werner may go back to this company.

When the sample for McNeal arrives it will be tested like previous samples.

Eugene asked if we have the final dimensions for the counters. Werner replied yes, to within 5 to 10%. The geometry is driven by largely by the size and placement of the SiPM's on the read-out board.

Read-out design

Fernando is finishing work on the BCAL read-out for the beam test. He will turn to work on the start counter soon.

Contract status

We discussed whether we should get started on this work with the design in its current state, with some questions unanswered. Eugene thought that we should aim for award of the contract at the beginning of the next fiscal year which means we have to start getting the paperwork moving now. Mark will send Werner a first draft of the documents to get started.

Simulation

Simon asked about the current HDDS geometry. The change from 40 counters to 30 counters has not been put in yet. Same for the new radial placement. Werner agreed to look into this.

Technical Design Report

Werner agreed to look at the start counter section.

Calibration and Alignment

Mark raised the issue of developing a conceptual design of how this should be done. This involves

  • identifying quantities to be calibrated
  • calling out data that needs to be taken, both the type and the amount
  • sketching the analysis procedure
  • noting dependencies on other detector systems

We will schedule a discussion for a future meeting.

Werner mentioned that he has had a plan to look into feeding LED test signals into the counters somehow. This is largely a mechanical problem.

Action Items

  • Get sample from McNeal and test it. -> FIU team
  • Write rough draft of contract documents and send to Werner. -> Mark
  • Bring geometry in HDDS up-to-date. -> Werner
  • Look at start counter section in the TDR. -> Werner
Retrieved from "https://halldweb.jlab.org/wiki/index.php?title=GlueX_Start_Counter_Meeting,_April_19,_2012&oldid=65296"