Diffractive Higgs studies with CMS and TOTEM Status

Diffractive Higgs studies with CMS and TOTEM: Status, plans and possibilities for Torino Monika Grothe TO-CMS meeting October 8 2004

Diffractive Higgs Production Exclusive diffractive Higgs production pp p H p : 3 -10 fb Inclusive diffractive Higgs production pp p+X+H+Y+p : 50 -200 fb -jet gap p beam gap H Advantages Exclusive: Jz=0 suppression of gg bb background Mass measurement via missing mass p -jet dipole p’ roman pots E. g. V. Khoze et al M. Boonekamp et al. B. Cox et al. … roman pots p’ h

Status: v Discussion on how collab TOTEM/CMS should look like still on-going v For time being: Joint diffractive and low-x working group as part of the PRS SW group v CMS aims at LOI on diffraction and fwd physics by March 2005 o circa 20 CMS groups have so far signed up for contribution o Albert de Roeck coordinates effort o for more details see Albert’s talk in last CMS week, on Sept. 27 v Recent new initiative in UK: R&D program for detectors at ~400 m o UK groups requested 1. 2 Mio. pounds for 2005 -2008 for R&D to develop cryostat that can house detectors (3 -D silicon one possibility) and for trigger studies o bolstered by interest from ATLAS and CMS o cryostats with embedded detectors could be installed in LHC upgrade after 2008, no interference with initial LHC startup o more details: see Albert’s 2 nd talk in last CMS week, on Sept 27

Status concerning trigger issues: v TOTEM to use from beginning CMS trigger and DAQ system o CMS GT reserved 16 bits for TOTEM trigger o Roman pots at 200 m will go into the L 1 trigger o Detectors at 400 m can only go into HLT if L 1 trigger has to occur within CMS L 1 latency of 3. 4 s v On-going work with CMS DAQ group, contact S. Erhan v Contact between TOTEM and CMS L 1 group up to now sporadic => I’m in contact with E. Radicioni and Marco Deile My plan for LOI: v L 1 rate and efficiency numbers for diff Higgs, generated with EDDE, without pileup and with pileup at Lumi 2 x 1033 and 1034 , first using only central CMS detector (Et/Ht algorithm) v Time permitting, study impact of using TOTEM T 1/T 2 veto counter which are available in OSCAR v Would also like to use Roman Pots, but for the moment only available in FAMOS, though porting to OSCAR should be simple (LUTs)

Level-1 Jets and HT HCAL Trigger tower ECAL HT = sum of scalar ET of all jets t veto patterns Pb. WO 4 crystal Advantage over total scalar ET: § Sums only over ET around local energy maxima § More robust against noise and minimum bias events Diff Higgs at L 1: L 1 cut on ET(2 jets)/HT § 4 x 4 trigger towers = region § Search for jets with sliding 3 x 3 regions window § Jet = 3 x 3 region with ET in central region above some threshold and with ET> ET in any of 8 outer regions § Jet = t if t veto off in all 9 regions

Current involvement of Torino: v My ‘Rientro dei cervelli’ grant for “Diffraction and diffractive Higgs production with CMS” v Plan to concentrate on L 1 trigger studies for diff Higgs v Have been working on these studies at U Wisconsin with S. Dasu (author of L 1 simulation code) and C. Hogg (first year Ph. D student) v Marta Ruspa currently visiting U Wisconsin to learn about the L 1 Calo trigger and its simulation code in ORCA -> L 1 ORCA code hasn’t been updated since L 1 TDR in 2000 -> none of on-going PRS studies take L 1 trigger into account => turn Marta into a competent user of the L 1 ORCA code => side-effects: o Torino group gains expertise in using CMS OSCAR/ORCA o U Wisconsin gets much-needed feedback on their code o CMS physics analyses will be able to include L 1 efficencies We made good progress so far, might even be able to have first rate plots for diff Higgs by end of Marta’s stay, in any case in time for LOI

Current involvement of Torino (cont): v Side remarks: Bristol group (GCT) has new Ph. D student at CERN interested in L 1 studies for diff Higgs => I’ll be back in Europe full-time by Dec. to take care of coordination Other possibilities for Torino involvement: Even if it is not possible to use detectors at 400 m in L 1, want to use them in HLT: v Need to develop trigger v R&D program for 400 m detectors just starting up, installation would happen only well after initial LHC start v This means will become full-fledged hardware effort only after muon chamber installation finished v In the meantime: Need MC studies