Diffractive Higgs studies with CMS and TOTEM:

Status, plans and possibilities for Torino

Monika GrotheTO-CMS meetingOctober 8 2004

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Diffractive Higgs ProductionExclusive diffractive Higgs production pp p H p : 3-10 fbInclusive diffractive Higgs production pp p+X+H+Y+p : 50-200 fb

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Advantages Exclusive: Jz=0 suppression of ggbb background Mass measurement via missing mass

E.g. V. Khoze et alM. Boonekamp et al.B. Cox et al. …

Status:

Discussion on how collab TOTEM/CMS should look like still on-going For time being: Joint diffractive and low-x working group as part of the PRS SW group

CMS aims at LOI on diffraction and fwd physics by March 2005o circa 20 CMS groups have so far signed up for contributiono Albert de Roeck coordinates efforto for more details see Albert’s talk in last CMS week, on Sept. 27

Recent new initiative in UK: R&D program for detectors at ~400mo 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 studieso bolstered by interest from ATLAS and CMSo cryostats with embedded detectors could be installed in

LHC upgrade after 2008, no interference with initial LHC startup

o more details: see Albert’s 2nd talk in last CMS week, on Sept 27

Status concerning trigger issues:

TOTEM to use from beginning CMS trigger and DAQ systemo CMS GT reserved 16 bits for TOTEM triggero Roman pots at 200m will go into the L1 triggero Detectors at 400m can only go into HLT if L1 trigger has to occur within CMS L1 latency of 3.4 s

On-going work with CMS DAQ group, contact S. Erhan

Contact between TOTEM and CMS L1 group up to now sporadic=> I’m in contact with E. Radicioni and Marco Deile

My plan for LOI:

L1 rate and efficiency numbers for diff Higgs, generated with EDDE, without pileup and with pileup at Lumi 2x1033 and 1034 , first using only central CMS detector (Et/Ht algorithm) Time permitting, study impact of using TOTEM T1/T2 veto counter which are available in OSCAR 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

ECAL

HCAL

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veto patterns

Trigger tower

4x4 trigger towers = region Search for jets with sliding 3x3 regions window Jet = 3x3 region with ET in central region above some threshold and with ET> ET in any of 8 outer regions Jet = if veto off in all 9 regions

HT = sum of scalar ET of all jets

Advantage over total scalar ET: Sums only over ET around local energy maxima More robust against noise and minimum bias events

Diff Higgs at L1:L1 cut on ET(2jets)/HT

Current involvement of Torino:

My ‘Rientro dei cervelli’ grant for “Diffraction and diffractive Higgs production with CMS” Plan to concentrate on L1 trigger studies for diff Higgs Have been working on these studies at U Wisconsin with S. Dasu (author of L1 simulation code) and C. Hogg (first year PhD student)

Marta Ruspa currently visiting U Wisconsin to learn about the L1 Calo trigger and its simulation code in ORCA

-> L1 ORCA code hasn’t been updated since L1 TDR in 2000-> none of on-going PRS studies take L1 trigger into account

=> turn Marta into a competent user of the L1 ORCA code=> side-effects:

o Torino group gains expertise in using CMS OSCAR/ORCAo U Wisconsin gets much-needed feedback on their codeo CMS physics analyses will be able to include L1 efficencies

We made good progress so far, might even be able to have first rate plotsfor diff Higgs by end of Marta’s stay, in any case in time for LOI

Current involvement of Torino (cont): Side remarks: Bristol group (GCT) has new PhD student at CERN interested in L1 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 400m in L1, want to use them in HLT: Need to develop trigger R&D program for 400m detectors just starting up, installation would happen only well after initial LHC start This means will become full-fledged hardware effort only after muon chamber installation finished In the meantime: Need MC studies