Hodoscope Replacement for E906

By

Rusty Towell

December 8, 2006

December 11, 2006 Review of FNAL E906

Outline

• Why Hodoscopes• Detector description• Scintillator material• Photomultiplier tubes• Schedule• The hodoscope group

December 11, 2006 Review of FNAL E906

Hodoscopes

• Used for triggering like in E866.

• Upgrades in design• Additional planes

• More selective trigger • efficiency monitoring• redundancy

• New material (higher efficiency)• Double ended read-out (better timing needed

due to the higher rates)

December 11, 2006 Review of FNAL E906

Hodoscope Planes(approximately the same sizes, changes highlighted)

E866 E906Statio

nX (in) Y(in)

1 48 40

12x2 2x16

2 66 51

2x16

3 106 96

12x2 2x13

4 117 120

16x2 2x14

Station

X (in) Y(in)

1 48 40

16x2 2x16

2 66 51

16x2 2x16

3 106 96

none 2x16

4 117 120Two @ 16x2 2x16

December 11, 2006 Review of FNAL E906

Typical y Hodoscope Plane St 1 and 2

16 channels

x

y

2 half planes

December 11, 2006 Review of FNAL E906

Double-ended y Hodoscope Plane St 3&4

Half planes at slightly different z positions to allow for double-ended readout.

x

y

December 11, 2006 Review of FNAL E906

Scintillator Material

• Old material is:• Too small (station 1)• Too thin (station 2)• Too old/crazing

• station 2 (1989)• station 3 & 4 (1982)

• Decreased efficiencies were observed in E866.• Therefore ‘new’ scintillator material and light

guides will be used.• Material for stations 1 and 2 will come from HERMES.• New material will be purchased for stations 3 and 4.

December 11, 2006 Review of FNAL E906

Photomultiplier Tubes

• Total number of PMTs needed for E906 is 384 plus spares.

• Reuse all good PMTs from E866. Total number of tubes was 198.

• An additional 250 tubes have been committed from ZEUS when DESY is decommissioned in fall 2007.

• All tubes will be tested.

December 11, 2006 Review of FNAL E906

Hodoscope Budget

• Scintillator and light guide material: • Scintillator: EJ-200 (same as Bicron BC-408)• estimated at $120 k plus contingency and inflation

based on a 2002 quote. • Updated quote received late last week came in slightly

lower.• Total budgeted is $153 k from DOE and $ 16 k from NSF.

• Photomultiplier tubes• All pmt’s will be reused from previous experiments.• The only costs will be in shipping and testing the tubes.• Total budgeted is 2k $.

December 11, 2006 Review of FNAL E906

Schedule

• Most of the labor intensive work on the hodoscopes (especially on station 3 and 4) will be done during the summer break from classes.

• PMTs testing, design work, purchases, etc. can be done during the school year.

• There should be no problem in completing the hodoscopes on time.

• The hodoscopes could be completed earlier if the funding profile allowed for materials to be purchased sooner.

December 11, 2006 Review of FNAL E906

Hodoscope TeamUIUC & ACU

• UIUC will rebuilt stations 1 and 2.• ACU will rebuilt stations 3 and 4.• ACU rebuilt and commissioned the

hodoscopes for E789 and E866.• Testing of the PMTs will be shared.• This team can construct the

hodoscopes needed for E906.