E906 Changes Paul E. Reimer 8 December 2006 Spectrometer Location Spectrometer’s 2 nd magnet Hodoscopes –Scintillator for Station 1 and 2 –Photomultiplier

E906 Changes

Paul E. Reimer

8 December 2006

Spectrometer Location

Spectrometer’s 2nd magnet

Hodoscopes

– Scintillator for Station 1 and 2– Photomultiplier tubes

DAQ/Trigger

28 December 2006 E906 Changes since Inception

Location Fermilab

Original Meson East is now not

Available Superconducting Cryo-

Module Test Facility (SCMTF)


Meson West

NM4 (KTeV)

Location Fermilab (cont)


Location Fermilab

NM4 (KTeV)– Beam lime below grade allows

for a horizontal bending spectrometer—bends + and - into earth. Easier assembly for magnets.

– Possibility to use KTeV Magnet– Nicer facility for physicists

Meson West– Vertical bend spectro.—bends +

into earth.– 2nd magnet (SM3) must be

assembled (but is available)


Beam Request and Structure

Old Plan was for 1 £ 1012 protons/s and accumulate 5.3 £ 1018 protons on target in 1 year– Unacceptable impact on other Fermilab proton users

New Plan– Cut impact on other proton users by ¼ – 2 £ 1012 protons/s– 5 s long slow extraction spill– Total of 5.3 £ 1018 protons in 2 years (with some allowance for

normal Fermilab maintenance shutdowns, etc


M1 Magnet New coils Reuse whole pieces of SM12

magnet yoke (SM12 was the 14.4 m dipole used by E866)


2nd Spectrometer Magnet

Originally proposed Jolly Green Giant, 1.65 T-m (500 MeV pT) 80 £ 50 in.

– In use by E907/MIPP (although their future is uncertain)– Possibly in need of repairs

Other magnets have become available:– SM3 (BTeV is no longer with us)

3 T-m, (900 MeV pT) 60 £ 60 £ 210 inches

– KTeV Magnet (CKM and KAMI are no longer with us)

¼2 T-m, (600 MeV pT ) 2m £ 2m £ 200 inches

Impact on measurements (Monte Carlo from ACU students):

– Momentum (and hence M and xF) resolution dominated by multiple scattering and energy loss in absorber until pT kick < 200 MeV

– Acceptance also approximately the same for pT kick of 900 to 400 MeV

Plan:– MWest—Fermilab reassembles SM3– NM4 (KTeV) relocate KTeV magnet to appropriate position


Scintillator for Hodoscopes: Station 1 and 2

Original plan was to purchase new material for all stations Current plan:

– Purchase new material for Stations 3Y, 4Xa, 4Xb, 4Y (Abilene)– Recover material for Stations 1X, 1Y, 2X, 2Y from HERMES

muon hodoscopes which will have to be refashioned and polished in one dimension. (Naomi Makins, Illinois)

– Purchase new light guide material for all stations.


Photomultiplier Tubes for Double Ended Readout

Original plan was to purchase ¼ 220 new 2” PMT’s to add double ended readout to Station 3 and 4 Hodoscopes, in addition to reusing E866 PMT’s

Current plan:– Recover 250 1.5” PMT’s/bases/shields from ZEUS at DESY

(Argonne’s HEP) rather than new purchase (more could be available)

– Cockroft Walton PMT bases with power supply

– Need to test PMT’s, both ZEUS and old E866


DAQ

Old plan was to borrow Fermilab E871 DAQ running Fermilab DART system– Still available to us (I verified this in November)– Do we really want the DAQ running on 10 yr old hardware?– DART is no longer supported at Fermilab; although, there is no

operational, Fermilab-supported system appropriate for E906

Solution:– JLab CODA system– Need to implement Nevis bus readout– Need to implement FERA readout

Either solution will need local (collaboration) expert(s)


Trigger

Old Plan was to Implement in copies of LeCroy Logic Units– Units no longer available– Expensive to duplicate units– Technology has evolved

New plan (Rutgers, Ron Gilman)– Implement in FPGA– Much cheaper, more flexible logic


Bottom Line

E906 has changed in terms of implementation Physics goals have not changed and will be reached with new

configuration

Hope to start construction in 2007 and start taking data in summer 2009

Documents

E906 Changes Paul E. Reimer 8 December 2006 Spectrometer Location Spectrometer’s 2 nd magnet Hodoscopes –Scintillator for Station 1 and 2 –Photomultiplier