Kaori Maeshima Fermilab Jan. 12, University Evolution: Search in High Mass Dilepton Channel in CDF Pre Run I Run 1A, Run 1B, and Run II Kaori Maeshima Fermilab at Waseda University, Jan 12, 2005

Kaori Maeshima Fermilab Jan. 12, University Why Search in Dilepton (ee,  ) channel? ● Theoretically: Interesting physics -- many different theoretical predictions ● Experimentaly: relatively small and well understood background. Z, Z*,  *,  TC,  TC, e Z' or what? Discovery Potential! Dilepton invariant mass (M(ll))

Kaori Maeshima Fermilab Jan. 12, University Why Search in Dilepton (ee,  ) channel? ● Theoretically: Interesting physics -- many different theoretical predictions we can test/search in this dilepton channel. – Extra dimension solutions to the Hierachy problem – Z' (higher gauge structure, -> U(1) ), E6, little Higgs model Z', SO(10), etc., etc.... – Technicolor model (r T, w T ) – RPV SUSY s-neutrino – lepton-quark compositeness –.....

Kaori Maeshima Fermilab Jan. 12, University Why Search in Dilepton (ee,  ) channel? ● Experimentaly: relatively small and well understood background. ee 2 two isolated e, E T > 25 GeV 2 central e (CC) or 1 central and 1 forward e (CP) missing Et significance < 2.5  2 isolated  P T >20 GeV |   1 |<1, |   2 |<1.5 Cosmic ray rejection cuts Muon System COT Plug Calorimeter Time-of-Flight Central Calorimeters Solenoid Silicon Tracker |  | < 1 1<|  |<3 |  | < 1.5 |  | < 1 Selection cuts

Kaori Maeshima Fermilab Jan. 12, University N obs N exp Mass (GeV/c 2 ) CC+CP High Mass Dielectrons Total of ~ dielectron candidates in 200 pb -1 data

Kaori Maeshima Fermilab Jan. 12, University High Mass Dimuons High mass dilepton spectra is consistent with background prediction ± ± ± ± ± ± ± ± ± N obs N exp Mass (GeV/c 2 ) Total of ~ 7500 dimuon candidates in 200 pb -1 data

Kaori Maeshima Fermilab Jan. 12, University CDF (D0) Z' Published Papers ● CDF: “Measurement of the e+e- invariant-mass distributions in pbarp collisions at root-s = 1.8 TeV”, PRL 67, 2418 (1991) ● CDF: “Search for new gauge bosons in anti-p p collisions at root-s = 1.8 TeV”, PRL 68, 1463 (1992) ● CDF: “Search for new gauge bosons decaying into dielectrons in anti-p p collisions at root-s = 1.8 TeV”, PRD 51, 949 (1995) ● CDF: “Search for new gauge bosons decaying into dileptons in anti-p p collisions at root-s = 1.8 TeV”, PRL 79, 2192 (1997) ● D0: “Search for additional newtral gauge bosons”, PLB 385, 471 (1996) ● D0: “Search for heavy particles decaying into electron positron pairs in p anti-p collisions”, PRL 87, (2001)

Kaori Maeshima Fermilab Jan. 12, University CDF (D0) Z' Published Papers ● CDF: “Measurement of the e+e- invariant-mass distributions in pbarp collisions at root-s = 1.8 TeV”, PRL 67, 2418 (1991), data, 4.05 pb-1, ee only, 387 Gev sm limit, compositness, 1310 fb limit. ● CDF: “Search for new gauge bosons in anti-p p collisions at root-s = 1.8 TeV”, PRL 68, 1463 (1992), data, 4 pb-1, ee and mm, 4 E6 models, 412 GeV sm limit, compositness limits, 1000 fb limit ● CDF: “Search for new gauge bosons decaying into dielectrons in anti-p p collisions at root-s = 1.8 TeV”, PRD 51, 949 (1995), data, 19.7 pb-1, ee only, 6 E6, 350 fb limit (> 350 GeV), 505 gev sm limit ● CDF: “Search for new gauge bosons decaying into dileptons in anti-p p collisions at root-s = 1.8 TeV”, PRL 79, 2192 (1997), data, 110 pb-1, ee and mm, 690 sm limit, 40 fb limit, 6 E6 limits. ● D0: “Search for additional newtral gauge bosons”, PLB 385, 471 (1996), data, 15 pb-1, 490 GeV sm limit, (sigZ'/sigZ) = 2.2*10-3, using sigZ(ee) = 218 pb (measuments of W and Z boson production cross section (run 1A), phys rev D 60, , 1999, then, sigZ' limit = 480 fb ● D0: “Search for heavy particles decaying into electron positron pairs in p anti-p collisions”, PRL 87, (2001), data, pb-1 TC, Z', Z'sm limit below 670 GeV, ~70 fb limit 148 mm 406 ee 7234 ee 2566 mm 1371 ee

Kaori Maeshima Fermilab Jan. 12, University Summary: CDF/D0 Z' results ee only ee and mm ee only ee and mm , ee and mm 4 pb-1, 1000fb 200 pb-1, 20 fb 50 times data, 50 times better cross section limit, but... mass limits improve very slow because s dropps very fast.

Kaori Maeshima Fermilab Jan. 12, University prospect of the search 50 times data, 50 times better cross section limit, but... mass limits improve very slow because s dropps very fast. ● Tevatron performance and prospect of Int. luminosity and it's affect for the search ● More Center of Mass Energy LHC

Kaori Maeshima Fermilab Jan. 12, University Status: Current CDF Data Taking Intial Luminosity vs Store Number June 2001 RUN II Jan ● Going up ● Dips (shutdowns) ● #stores/year ● 1240 (2002) ● 770 (2004)

Kaori Maeshima Fermilab Jan. 12, University Status: Current CDF Data Taking Intial Luminosity vs Store Number June 2001 RUN II Jan ● Going up ● Dips (shutdowns) ● #stores/year ● 1240 (2002) ● 770 (2004) Main cause of the sharp rise in the peak luminosity in 2004: alignment a huge difference in ave. store hours (much more stable operation). allow enough time to accumulate large stack of pbars

Kaori Maeshima Fermilab Jan. 12, University Status: Current CDF Data Taking (cont.) Int. Lum vs Store Number June 2001 RUN II Jan ● Going up sharper ● Flats (shutdowns) ● #stores/year ● 1240 (2002) ● 770 (2004) Delivered To tape ~ 500 pb-1 on tape

Kaori Maeshima Fermilab Jan. 12, University Status: Current CDF Data Taking (cont.) Data taking Efficiency vs Store Number June 2001 RUN II Jan ● Going up in 2002 ● Spreads, consistency ● Dips ● beam cond. ● w/wo Silicon ● Effort to sustain ● #stores/year ● 1240 (2002) ● 999 (2003) ● 770 (2004)

Kaori Maeshima Fermilab Jan. 12, University Luminosity and Efficiency during a typical store ● run ● ● 57e30 lum begin ● 13e10 lum end ● 26 hours store ● 2.4 pb-1 delivered ● 2.1 pb-1 to tape ● 85% efficient The same duration of time at the beginning or the end of the store corresponds more than 3 times difference in luminosity.

Kaori Maeshima Fermilab Jan. 12, University Operation is easier with the longer store hours The same duration of time at the beginning or the end of the store corresponds more than 3 times difference in luminosity. ● There are much more chance things go wrong at the beginning of the store. – luminosity is high ● high noise ● high trigger rate – start of a run after no beam period. Ops person comes to the conrol room beginning of each store. >30 hour store vs < 20 hours (shot setup ~ 3 hours).

Kaori Maeshima Fermilab Jan. 12, University Status: Current CDF Data Taking (cont.) days Delivered and CDF Acquired Luminosity per FY in RUN II

Kaori Maeshima Fermilab Jan. 12, University What to expect in FY summer 04 shutdown: electron cooling installed in the recycler FY05 run: commitioning electron cooling ( no gain from it, yet) summer 05 shutdown: 2 major items planed - D0 run 2B upgrade * L00 tracker * complete trigger upgrade - Reconfig C0 for BTeV (quite a big job) - reconfig. Accumulator (electron cooling must be working for this.) no more large stack after this. FY06 - FY 09: just take data with minor adjustment goal: 4.7 fb-1 (case: electron cooling not working) fb -1

Kaori Maeshima Fermilab Jan. 12, University upgrade needed in CDF work in progress (modification are all to do with faster trigger-rate): SVT (~5 times faster readout. L2 rate: ) Pulsar: running in pararell with alpha now XFT: reconfig. TDC: faster DSP code Event builder: 20 Mb/sec -> 60 Mb/sec pararell CSL

Kaori Maeshima Fermilab Jan. 12, University prospect with 8.5 fb ee only ee and mm ee only ee and mm , ee and mm 4 pb-1, 1000fb 200 pb-1, 20 fb 1000/(8500/4) = 0.47 fb good limit, but better to find one.