Revision as of 20:31, 5 December 2011

previous pages (some info outdated)

Forward Calorimeter

Largeangle Calorimeter

file dir

/u/group/halla/www/hallaweb/html/12GeV/SoLID/download/ec

http://hallaweb.jlab.org/12GeV/SoLID/download/ec/

the "doc" sub-directory has collective of documentation for R&D

beam test plan

We plan to test the COMPASS shahlyk modules.

The goal is to learn the feature and performance of the modules. We will test energy, position and time resolution and use the results to anchor our simulation. This will thus help us design the future SoLID prototype.

We will use the TPE (two photon exchange) calorimeter for test. It consists of 30 4x4cm COMPASS modules in 5x6 array and sit in a metal box/frame. The calorimeter was used in TPE experiment in HallB and currently sits at ODU with Larry Weinstein's group. They need to be returned to Will Brooks at Chile in Summer 2012.

The test time is Nov 2012 - May 2012, this includes planning, bench test and beam test.

The bench test will be held at in Jlab. We will use cosmic rays to do gain match. Two scintillator bars will be used for trigger.

For beam test, The plan is to have it in HallB under photon tagger. After passing through a photon radiator and swept by tagger magnet, electrons will 5-95% of beam energy will pass photon tagger and hit on the floor. We will place the calorimeter module on the floor aligned with electrons at various locations for test. refer to the plot at [1]

Currently, Matthew Shepherd's group at Indiana University is doing HallD lead glass FCAL test there. They have 25 4x4cm modules in 5x5 array mounted on a rail. Two of 5 scintillator bars on top of each others are used as trigger in a box above the calorimeter modules. Another small scintillator is mounted directly under the tagger counter to work as a veto at offline stage. Their readout is FADC. see their setup at [2] and [3]. We plan to do test similar to their setup.

About materials we need for the test. The modules can be borrowed. The readout (PMT/base/housing) need to be borrowed from DVCS Proton Array with an adapter or new housing to be able to connected to the modules. For electronics, we will find supply in hallA and HallC. For supporting structure, we need to make them or borrow them.

We are in talk with Indiana University about borrowing their supporting structure and electronics. That depends on how soon they can finish their test and if others will use some of that. To have our modules put into the their supporting structure, we need to make a mounting.

For man power, Only Zhiwen is on it now and hopefully W&M will come on board.

Note:

1. the g2p/gep in HallA has target coil and septa blocking forward angle up to 30 degree, this makes it impossible to have elastic electrons with good rate for test.
2. more info about the HallD FCAL test is at their wiki [4]. Their writeup, OSP and talk are also collected here [5]

talks and notes

2011_10 collaboration meeting by Mehdi Meziane

2011_09_30 Jlab Physics Division Brain Storm Session by Jin Huang

2011_09_21 Update by Mehdi Meziane

2011_06 collaboration meeting by Zhiwen Zhao for forwardangle Calor

2011_06 collaboration meeting by Jin Huang for largeangle Calor

2011_03 collaboration meeting by Zhiwen Zhao for forwardangle Calor

2011_03 collaboration meeting by Jin Huang for largeangle Calor