Revision as of 16:34, 19 January 2012

Thursday, January 19, 2012
10:00 am EST
JLab: CEBAF Center, Room F326

Agenda

1. Announcements
2. Minutes from the last meeting
3. Mechanical design: Tim, Chuck
4. Prototype status: Paul, Sasha
5. Contract Status: Mark

Communication

Videoconference

1. ESNet: 8542553
2. EVO: EVO site

Slides

Talks can be deposited in the directory /group/halld/www/halldweb1/html/talks/2012-1Q on the JLab CUE. This directory is accessible from the web at https://halldweb1.jlab.org/talks/2012-1Q/ .

Chairman's Cell Phone

(757)504-0664.

Minutes

Present:

• FSU: Paul Eugenio, Sasha Ostrovidov
• JLab: Eugene Chudakov, Chuck Hutton, Mark Ito (chair), Tim Whitlatch, Beni Zihlmann

Phototube Purchase

Beni reviewed the proposal he floated last month along with the subsequent discussion on the email list (see the items in the "PMT choice for TOF" thread). We agreed that, all things considered, we should go ahead an adopt his proposal and initiate the purchase of the ten-stage tubes for the entire array. Some things we need to bear in mind going forward:

• Eugene suggested that we have amplifier ready if needed (see "subsequent discussion").
• We still want to test eight-stage tubes. FSU has a couple of these and will pursue these tests.
• We want to have a mechanical design that allows replacement of tubes in the high-rate area with reasonable effort during a shutdown period.

Mark will initiate writing of the PR.

Mechanical Design

This morning there was a phone conference to discuss issues with the light guides for the half-width counters. Present were Paul Eugenio, Kurt Koetz, Randall Smith, and Ian Winger at FSU and Chuck Hutton at JLab. They agreed on:

• adding 1 cm flat sections, as we have for the full-width guides
• reducing the over-all length by 4 cm to avoid interference with the carriage

Another meeting is scheduled for Tuesday, January 24 at 9:00 am to discuss progress.

Contract

• Paul has starting on construction documentation.
• Mark has not heard anything from Procurement on the RFP. He will check on progress.

Prototype Status

• replkaced a trigger pmt • time resolution 98 ps • get 90 ps in center of counter • speed of light as function of tube ∘ use source, measure time as function position

constrution • example of latest light guide in hand • structure for gluing three modules at a time ∘ ian is work on it ∘ ∘