cms status report

CMS Status ReportCMS Status Report

Darin AcostaUniversity of Florida

Welcome to the inverse femtobarn era!

21 September 2011 LHCC CMS Status Report -- D. Acosta 2

Recorded 3.1fb-1 of 3.4 fb-1

delivered Data-taking efficiency is

about 90%

Certification for physics analyses (up to August Stop) 84% for all systems perfect 91% for muon analyses

(without calorimeters)

Used in 2011 physics analyses reported here: 0.23 – 1.7 fb-1

most at 1.1 fb-1

Luminosity uncertainty is 4.5%

Pile-Up

The number of reconstructed vertices after the August Technical Stop increased by factor 1.5 (β*=1.5m 1m ) Fills start with ~15 pile-up

interactions Vertex reconstruction still quite

linear with luminosity

Total inelastic cross section also has been measured from pile-up

σinel(pp)= 68.0 ± 2.0 (Syst) ± 2.4 (Lum) ± 4 (Extrap.) mb.


Pile Up

20 vertices

Averaged over fills.

Nrec~ 0.7 x Npu

(PAS FWD-11-001)

before after

Operational Status

Live detector channels Very stable over 2010-11 Forward pixels recovered some channels

Preshower has slight drop due to leakage current in one sensor type

Computing Data rates and storage have been as expected

(LHC live time and trigger rate)21 September 2011 LHCC CMS Status Report -- D. Acosta 4

95%

2010 2011

CMS High Level Trigger Performance

The CMS HLT is performing well in the high luminosity environment

Trigger algorithms and menus have increased in complexity Over 200 multi-object triggers

including tau and b-jet triggers, in addition to single object triggers for electrons, photons, muons, jets, total energy, & missing transverse energy (400 total paths)

Successfully using algorithms such as Particle Flow tau reconstruction


Isolated Muon PT > 12 GeV & Hadronic Tau ET > 20 GeV trigger

TAU + MUON

Physics Analyses on 2010 Data


https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResults Papers, and Physics Analysis Summaries (PAS): http://cdsweb.cern.ch/collection/CMS

69 published, 7 in CWR, 18+ in preparation

https://twiki.cern.ch/twiki/bin/view/CMSPublic/PhysicsResults

http://cdsweb.cern.ch/collection/CMS




69 published, 7 in CWR, 18+ in preparation

CMS reached 100 publications on August 3rd 75 from LHC collision data, 24 from the cosmic-ray runs of late 2009 1 is the CMS detector paper.






Summer conference results all new since last LHCC meeting !

Cannot cover it all here

5 submitted, 45 PAS

PAS PHY-11-000



Standard Model

Electroweak: access to proton PDFs

Wμν charge asymmetry vs. ημ W+charm access to strange


PAS EWK-11-005, 013

R±c = σ(W+c)/σ(W-c)=0.92 ±0.19(stat.)±0.04(syst.)

Rc = σ(Wc)/σ(W+jets)=0.143 ±0.015(stat.)± 0.024(syst.)NLO predictions:R±

c = 0.91±0.04 Rc =0.13±0.02

Secondary vertex decay length discriminator

Top: tt Cross Section, 1.1 fb-1


PAS TOP-11-003, 5, 6, 7

σ(NLO)=158±24 pb

Lepton+jets+b-tag CMS most precise to-date !

Dilepton channel (ee,eμ,μμ) Require at least 1 b-tag

Dilepton channel (μ-τ) Reconstruct hadronic tau decay

All-hadronic channel kinematic fit for mtop

QCD shape from anti-b-tag data

20

11

Top Charge, Mass Asymmetries, 1.1fb-1

Top charge asymmetry Larger than expected

@ Tevatron Lepton+Jets channel Δ(|η|) = |ηt| - |ηtbar|

AC = [N(Δ>0) - N(Δ<0)]/Ntot

= -1.6 ± 3.0(stat) +1.0-1.9(syst) %

AC (theory) = 1.3%

t-tbar mass difference Muon+jets channel Kinematic fit to the mass of the hadronically decaying top Ideogram method

Likelihood calculated for each event to be consistent with mt

Ideogram method applied separately to μ++jets and μ-+jets Δm(t-tbar) = -1.20±1.21(stat)±0.47(syst) GeV


PAS TOP-11-014, 019

Exceed’s Tevatron precision

Search for Bs(d) μμ, 1.1 fb-1

Decays are highly suppressed in the SM BR(Bs μμ): (3.2±0.2)x10-9, Bd μμ: (1.0±0.1)x10-10

Indirect sensitivity to new physics MSSM: BR∝(tanβ)6

Blind analysis B+ J/ψ K+ used for normalization B0 J/ψ ϕ used as control regions for efficiencies

Events observed in the unblinded windows are consistent with bkg. plus SM expectations.

CMS BR Limits at 95% CL Bsµ+µ− < 1.9×10−8

Bdµ+µ− < 4.6×10−9


arXiv 1107.5834accepted by PRL

CMS + LHCb Combination Bs μμ

CMS BR Limit Bsµ+µ− < 1.9×10−8

LHCb BR limit Bsµ+µ− < 1.5×10−8

Combination of LHCb+CMS: Bsµ+µ− < 1.08×10−8

The value of CLs is in good agreement with background + SM


LHCb-CONF-2011-047CMS PAS BPH-11-019

The Higgs

Overview of Searches

Light Higgs Hbb Hττ Hγγ HWW HZZ4l

Medium to Heavy Higgs HWW2l2v (+jets) HZZ (2l2j, 2l2v, 4l, 2l2τ)


Hbb, 1.1 fb-1

Search strategy: Associated production with W/Z Boosted W/Z topology, with

H back-to-back with W/Z 2 b-jets (~10% mass resolution) 5 topologies:

WH μvbb, evbb ZH μμbb, eebb ZH vvbb

Two complementary analyses: Cut and count in Mbb

MVA with boosted decision tree

Yields are in good agreementwith data-driven backgroundestimates


PAS HIG-11-012

BDT analysis

Hγγ, 1.7 fb-1


PAS HIG-11-021

MC for illustration only

Strategy 2 isolated γ’s with PT>40, 30 GeV Data divided into 8 categories

depending on resolution and pT(H) σeff(mass) varies from 1.4 – 7.9 GeV

Background shape fitted by2nd order polynomial in each category

Signal energy resolution extractedfrom Zee data

Hτau τau, SM and MSSM, 1.1-1.6 fb-1

SM categories VBF: 2 jets with Δη>3.5, mjj>350 Non-VBF: <2jets or 2 failing VBF tag

MSSM categories B-tag: ≥1 b jet pT>20 Non-b-tag: <2 jets and no b-tags

Topologies μτh, eτh, eμ (1.6 fb-1), μμ (1.1fb-1) τh ID by “hadron plus strips”,

6% efficiency uncertainty Fit visible mass distribution


PAS HIG-11-020

Hτau τau, MSSM Exclusion


HWW2l2v, 1.6 fb-1

2 isolated leptons, large MET,no b-tags (to suppress top)

3 categories 0, 1, 2 jets (VBF)

No mass peak Kinematic discrimination by

Mll and Δϕll , exploiting scalar decay


Exclude 147–194 GeV @ 95% CL (130-200 expected)

PAS HIG-11-014 EWK-11-010

σ(ppW+W-+X)= 55.3 ± 3.3(stat.)±6.9(syst.)±3.3(lumi) pbσ(NLO)=43±2pb

HZZ 4l (l=e,μ 1.7 fb-1), 2l2τ (1.1 fb-1)


PAS HIG-11-015, 013 EWK-11-010

“Golden” decay mode

4l mass resoln. is O(2-3) GeV

σ(ppZZ+X)= 3.8+1.5

-1.2(stat.)±0.2(syst.) ± 0.2(lumi) pb

σ(NLO)=6.4±0.6pb

HZZ 2l2v, 2l2j


PAS HIG-11-016, 017

CMS Preliminary

ZZ2l2v Zll Large MET No b-tag jets MT (2l2v) window

ZZ2l2j Likelihood

discriminant based on angular correlations

4 categories based on # b-tags, and a quark/gluon discriminant

Summary of all Searches

Solid lines: observed limits @ 95% CL Dashed lines: expected limits


PAS HIG-11-022

Σ (all this work)

SM Higgs Combination

Disfavoured mass region for minimal SM Higgs: Expected: 130 – 440 GeV Observed: 145-216, 226-288, 310-400 GeV


PAS HIG-11-022

Higgs with 4 Fermion Generations, 1.1 fb-1

Combination of analyses

Heavy 4th fermion generation coupling to SM Higgs disfavoured over mH=120—600 GeV @ 95% CL


PAS HIG-11-011

Overall Search Strategy Inclusive topologies not tied to specific models,

typically but not always with assumption of MET (dark matter)

Generally several approaches within each category, as well as several search regions

Additionally add b-tagging to some categoriesTargeting strongly produced squarks and gluinosEstablish data-driven estimates of backgrounds


High yield, high bkgnds. Rare, low bkgnds.(With Z+MET) (And γ+MET)

0 Lepton: new search using MT2, 1.1 fb-1

21 September 2011LHCC CMS Status Report -- D. Acosta29

“Stransverse” mass:

Extension of transverse mass totwo undetected particles (LSPs)

Endpoint corresponds to particle massesUsed here as a discovery discriminant for SUSY: MT2~0 for fake MET, MT2~MET for signalTwo signal regions (high MT2, low MT2 + b-tag)

MT2>400Nj ≥ 3

PAS SUS-11-005

X1

X2

0 Lepton: “αT” Approach, and traditional jets+MET, 1.1fb-1

QCD dijets have edge at 0.5 Processes with real MET have

tail above 0.5 Events with >2 jets are

clustered into 2 pseudo-jets Perform shape analysis of

vs. HT

Traditional jets + MHT

≥3 jets and 3 signal regions in HT (500, 800)and MHT (350, 500)

No excess observed over data-driven bkgds.


arXiv:1109.2352

Nj≥2, HT>375

PAS SUS-11-004

MHT (n.b.

)

Single Lepton Search, 1.1 fb-1

Exactly 1 isolated lepton pT>20 (e or μ), ≥3-4 jets, large MET and HT

Two approaches to define signal regionsand to measure backgrounds Use relationship between lepton pT

spectrum and MET (in SM) to predict bkgnd. with HT > 500

Use helicity structure of V-A coupling to W


PAS SUS-11-015

Total bkg

Consistent with SM.Similar limits achieved in both approaches

Same Sign Dileptons, 1 fb-1

Clean signature with low SM bkgnds. Consider ee, eμ, μμ, eτh, μτh, τhτh

Complementary baseline selections, used to check bkgnd predictions Inclusive SS dileptons with HT>200 High PT SS dileptons with HT>80 Dileptons with τh and HT>350, MET>80

Define several search regions per selection with tighter cuts on HT and MET:


PAS SUS-11-010

Inclusive and τh

High PT

Putting it all Together in CMSSM


Summary in Several Simplified Models


T1

T2

T5zz

T1lnu

GGM SUSY: Photon(s) + MET, 1.1 fb-1

Diphoton search for general gauge mediated SUSY with the gravitino as the LSP, extended to single photons

Two topologies with large MET 2 or more isolated photons

ET>45, 30 and 1 jet 1 isolated photon ET>75, ≥3 jets

Backgrounds without real MET(QCD with fake γ’s) from data


PAS SUS-11-009

Di-γ

Other Exotica

Dilepton Resonance Search,1.1 fb-1

Search for new gauge bosons or new symmetries (EDs) yielding high mass narrow dilepton resonances (ee, μμ)

95% CL mass limits:


PAS EXO-11-019

Z’ SSM Z’ Psi RS G* k =0.05 RS G* k =0.1

1.94 TeV 1.62 TeV 1.45 TeV 1.78 TeV

Upper limit on the ratio of Z’ or GKK to SM Z production

W’ Gauge Boson Search, 1.1 fb-1

Isolated single electrons, muons


PAS EXO-11-024

W’ with SM couplings excluded @ 95% CL with mass below 2.27 TeV

eμ

combined

e

μ

Dijet Resonance Search, 1.0 fb-1

Search for new narrow resonances in the dijet mass spectrum Templates based on qq, qg, and gg final states

Utilize wide jets to recover radiation (ΔR<1.1)


arXiv:1107.4771

String resonance

E6 Diquark q* Axigluon/coloron

W’

4.0 TeV 3.52 TeV 2.49 TeV 2.47 TeV 1.51 TeV

95% CL mass limits:

tt Resonance Search in Boosted Hadronic State, 0.9 fb-1


PAS EXO-11-006

Type 1Type 2

Using l+jets sample

Search for heavy resonances (Z’) decaying to top pairs in boosted regime

Classify boost of hadronic decay:1. Merged into single jet2. 2 out of 3 jets merged

Search for types 1+1 and 1+2 2 algorithms to tag merged jets using C-A algo with

R=0.8 using mjet, # subjets, etc. Particle flow inputs

Vector-like Top Quark and 4th Generation

Tt Z Search for FCNC decay of a heavy quark T t Z0

If vector-like, as in Little Higgs theories, could have large BR Full topology: Search for Z(ee or μμ) + additional lepton + at least 2 jets m(T) > 475 GeV @ 95% CL

b’tW Search for trileptons or same-sign leptons, + b-jet m(b’)>495 GeV @ 95% CL

t’bW l+jets: Search for isolated e/μ, large MET, ≥4 jets, b-tag Dileptons: (ee, eμ, μμ), MET, ≥2 jets, 2 b-tags m(t’)>450 GeV (l+jets), 422 GeV (dilep)


PAS EXO-11-005

PAS EXO-11-036, 050, 051

Exotica Grand Summary


TeV TeV

95% CL exclusion limits

Summary

These are definitely NOT austere times for our science! A very rich physics program has opened up with the first

inverse femtobarn from the LHC ! A broad set of tools and strategies have been developed

SM Reaching precision era, confronting predictions

Higgs No evidence yet, although wide mass regions for minimal SM

Higgs are becoming disfavoured at 95% CL (also heavy 4th generation fermion coupling)

SUSY and Exotica Sensitivity to squark and gluino masses in range 0.5 – 1 TeV Many resonant/non-resonant signals sought

It is a challenge to keep pace with the LHC, but it’s also a very nice situation to be in. Exciting times! Thanks to CERN and the LHC team !


Backup

21 September 2011LHCC CMS Status Report -- D. Acosta 44

Electroweak: Dibosons (WW, WZ, ZZ), 1.1fb-1

Measure backgrounds to high mass Higgs search Test for anomalous TGCs

WW (ee,eμ,μμ) Jet and soft b-tag veto Use MET transverse to closest lepton

WZ (eee,eeμ,eμμ,μμμ)

ZZ4l (l=e, μ, or τ)


σ(ppW+W-+X)= 55.3 ± 3.3(stat.)±6.9(syst.)±3.3(lumi) pb;

σ(ppWZ+X)= 17.0 ± 2.4(stat.)±1.1(syst.)±1.0(lumi) pb;

σ(ppZZ+X)= 3.8+1.5-1.2(stat.) ± 0.2(syst.) ± 0.2(lumi) pb;

PAS EWK-11-010

WZ

WW

σ(NLO)=43±2pb

σ(NLO)=19.8±0.1pb

σ(NLO)=6.4±0.6pb

Hbb Combined Limits, 1.1fb-1


BDT analysis Mbb analysis

PAS HIG-11-012

Local significances and combination

p-value estimates probability of upward background fluctuation as high or higher than the excesses observed in data

Global p-value estimated to be ~0.4


CMS PAS 11-022

Dilepton Resonance Search,1.1 fb-1

Search for new gauge bosons or new symmetries (EDs) yielding high mass narrow dilepton resonances

Relatively clean final state


PAS EXO-11-019

Combined Dilepton Limits, 1.1 fb-1

Z’ SSM Z’ Psi RS G* k =0.05 RS G* k =0.1

1.94 TeV 1.62 TeV 1.45 TeV 1.78 TeV


PAS EXO-11-019

95% CL mass limits:

Upper limit on the ratio of Z’ or GKK to SM Z production

WR and Heavy Neutrino Search, 0.24 fb-1

L-R symmetric extension to SM with parity spontaneously broken Generates WR and Z’ bosons

plus heavy RH neutrinos

Search for resonance structure in ljj and lljj Impose cuts m(ll)>200 and m(lljj)>520 Search in 200 GeV wide bins


PAS EXO-11-002

4th Generation Search: b’tW, t’bW

b’ Search for trileptons or same-sign leptons, + b-jet

t’ l+jets: Search for isolated e/μ, large MET, ≥4 jets, b-tag Dileptons: (ee, eμ, μμ), MET, ≥2 jets, 2 b-tags


PAS EXO-11-036, 050, 051

m(b’)>495 GeV @ 95% CL

m(t’)>450 GeV (l+jets), 422 (dilep)

tt Resonance Search, 0.9-1.1 fb-1

Boosted top high mass and intermediate mass search:

Semileptonic search in μ+jets: Similar sensitivity


PAS EXO-11-006

PAS EXO-11-055

cms status report

Documents

preparation cms

cms detector paper

lhcc meeting

acostaphysics analyses

physics analysis summaries

muon analyses

pas ewk

single object triggers