e906 changes paul e. reimer 8 december 2006 spectrometer location spectrometer’s 2 nd magnet...
TRANSCRIPT
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)
38 December 2006 E906 Changes since Inception
Meson West
NM4 (KTeV)
Location Fermilab (cont)
48 December 2006 E906 Changes since Inception
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)
58 December 2006 E906 Changes since Inception
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
68 December 2006 E906 Changes since Inception
M1 Magnet New coils Reuse whole pieces of SM12
magnet yoke (SM12 was the 14.4 m dipole used by E866)
78 December 2006 E906 Changes since Inception
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
88 December 2006 E906 Changes since Inception
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.
98 December 2006 E906 Changes since Inception
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
108 December 2006 E906 Changes since Inception
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)
118 December 2006 E906 Changes since Inception
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
128 December 2006 E906 Changes since Inception
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