LHC status and plan

LHC status and plan

Osamu Jinnouchi(Tokyo Institute of Technology)

Annual meeting for ILC detectors

2011/03/09-11

contents

• Brief overview of the ATLAS and 2010 LHC run

• Skip the SM measurements (sorry!)

• Higgs searches in 2010 and future

• SUSY searches in 2010 and future

• Upgrade plan of LHC/ATLAS

2011/3/9 JINNOUCHI LHC/ATLAS 2

N.B. my talk is heavily biased to ATLAS results

Very short introductionShort history of LHC pp runs:

•2009.11.23 the first collision @ 900GeV

•2009.12.14 collision at 2.36TeV (energy frontier)

•2010.03.30 started 7.0TeV run it lasted until the end of 2010 Oct.

•integrated L=45 pb-1 recorded by ATLAS

•established peak L=2x1032cm-2s-1 (2x 2010 target luminosity)

ATLAS status

•all systems >97% channels operational (LAr: due to the noise bursts and HV trips partially recovered offline)

•good quality data > 94%

Immediate future plan:

•re-start up the 7.0TeV run in March 2011 (last week)

•in 2012, continue the operation and possibility of 8.0TeV run

•long planned shutdown after 2013preparing for the higher energy (13-14TeV)

2011/3/9 JINNOUCHI LHC/ATLAS 3% of good quality data

initial target

ATLAS detector performance in 2010• Inner detector

• momentum scale known to 1% level (<100GeV)

• reconstruction eff > 99% (muons > 20GeV)

• material distribution known better than 10% (goal is 5%)

• EM Calorimeter

• scale uniformity ~2% in eta, <0.7% in phi (goal is < 1%)

• energy scale known to < 1% (goal is 0.1%)

• electron ID efficiency known with ~1% precision

• HAD Calorimeter

• Jet energy scale uncertainty 4~5% (goal is 1%)

• missing Et : good MC/data agreement no tail from instrumental origin after calibration with 15M minbias

• MUONS

• momentum scale known to 1%

• momentum resolution known to rel. 10%

• reconstruction eff known to 1-2% (goal is 1%)

• Trigger / Data GRID transfer

• Luminosity 2010 (Van der Meer scan)

• final uncertainty 3.2% (most of the papers used the previous estimation 11%)


Rate (2010/ design)Bunch crossing: 1MHz/40MHzLevel-1: 20kHz / 75kHzLevel-2: 3.5kHz / 2kHzEF: 300Hz / 200HzGRID: 1-4GB/s / 2GB/s

still room for improvements toward ultimate precisionbut pretty good for a first year performance

Higgs Searches and Prospects

(SM/MSSM)


Higgs search channels at LHC• Two main production processes

• Gluon fusion (GGF)

• dominates by a factor of 10

• Vector boson fusion (VBF)

• characteristic signature(two forward tagging jets & rapidity)

• Main decay channels

• HWW

• dominant at intermediate region and in high mass region

• HZZ

• clean signal in 4-lep final state

• H• low BR, important in low mass region

• Hbb

• high BR, large QCD background

• H• important in low mass region, important

channel for MSSM higgs


Higgs search in 2010 ATLAS data

The analyses and approval processes on going for 36pb-1

: highest/fastest sensitivity, exclusion result approved in ATLAS and shown today

: background estimation approved shown today

rest of the channels under the approval processes

(please wait for the JPS or other meetings)

: exclusion result, coming soon

: coming soon

: a bit later

: a bit later

• : coming soon


SM

Hig

gs s

earc

h

MS

SM

Hig

gs

• common requirements• two opposite charge leptons (ee//e)

1st > 20GeV, 2nd >15GeV

• Mll > 15GeV, |Mll-MZ|>10GeV (ee/)

• missing ET> 30GeV

• separate search into 0,1,2 jet bins (>25GeV)(different productions, bkgs differ)

• channel specific selections

• 0-jet

• pT(ll)>30GeV (Drell-Yan suppression)

• 1-jet, 2-jet

• b-jet veto (top suppression)

• vector PT sum< 30GeV (soft gluon radiation suppression)

• |m-mZ|>25GeV(Z veto)

• 2-jet • VBF cuts


0-jet 1-jet 2jet

Jet multiplicity

H+0j

H+1j

[ATLAS-CONF-2011-005]


• exclusion limits from this channel

• 95% CL exclusion limit in multiples of the SM cross section, using Profile Likelihood method with a Power Constrained Limit (PCL) for the 35pb-1 2010 data

• ATLAS excludes at 95% CL SM-like Higgs boson with a production cross section of 1.2 x SM (observed), 2.4 x SM (expected) at MH=160GeV

This is the only higgs exclusion limit plot with data, I can show you today

with the first year of 35pb-1data, we already got very close to the Tevatron limit

This is the only higgs exclusion limit plot with data, I can show you today

with the first year of 35pb-1data, we already got very close to the Tevatron limit

[ATLAS-CONF-2011-005]

• Backgrounds

• Irreducible (qq,qq, qgq)

• reducible

• di-jet, -jet : jet fake

• DY Zee: e fake

• Data driven bkg estimation

• signal region: two photons pass isolation + tight photon selection

• double sideband method to extract the compositions of the bkg samples

• data-driven estimate of , j, jj events in the signal region

• Drell-Yan: e fake rate estimate


Isolation for 2nd

ETisol[GeV]

ETisol[GeV]

Isolation for 1st

photon IDpass

photon IDfail

photon IDpass

photon IDfail

m distribution for the signal region

yellow band = (NLO) norm + (j+jj) data driven

[ATLAS-CONF-2011-004] net samples: event with two objects passed loose photon ID

new projected sensitivity at 1fb-1

• uses observed diphoton distribution, rescaled to 2011 luminosity (1fb-1)

• this channel can exclude 3.2-4.2 x SM for range MH=110-140GeV

• dashed line : degraded photon energy resolution (pessimistic assumption)

• similar results to previous estimation (pure simulation)

• exclusion sensitivity with 37pb-1 is about to be released


[ATLAS-CONF-2011-004][ATLAS-PUB-2010-009]

7TeV 1fb-1

SM Higgs sensitivity in 2011 and beyond


• with 1fb-1 of data at 7TeV, ATLAS expects median 95% CL exclusion over the range 130-460GeV

• challenge is at low mass (require 4(3)fb-1with 7(8)TeV to cover down to LEP limit, which might be possible by the end of 2012)

• with integrated luminosity 5-10 fb-1, ATLAS will move towards discovery over a wide mass range

expected limit in 2011with basic scenario (1fb-1)

[ATLAS-PUB-2011-001]

discovery reach

SUSY Searches and Prospects


Expected SUSY signatures at LHC

• R-parity conserving models

• high cross sections for gluinos/squarks production

• high-pT multi jets (and leptons) from cascade decays

• stable LSP

• large missing Et

• no mass peak excess in the tail of the Meff distributionaccurate understanding of detector and bkg essential

• other varieties of models are also under exploit (not shown today)

• R-parity violation models (kink inside ID)

• more exotic signatures (NLSP decay in detector, slow heavy ionizing particles, R-hadrons, sparticle stop in the calorimeter, etc)

• Two 2010 results “OUT” from ATLAS

• 0 lepton + multi(2,3,more)-jets + MET (arXiv:1102.5290)

• squark→q+LSP, gluino→q+squark+LSP

• QCD bkg control is critical

• 1 lepton + multi(2,3,more)-jets + MET(arXive:1102.2357)

• cascade includes electroweak decays

• dominant bkg: ttbar, W, MC shape + normalization from data


0 lepton analysis

• require exactly 0 lepton (pT>10GeV)

• need to suppress QCD bkg: tight cut adopted

• 1st jet > 120GeV

• 2nd (+3rd ) jets >40GeV

• missing ET>100GeV

• dominant bkg’s: W+jets, Z()+jets

• 4 signal regions defined (target heavy/light qq, gg, gq) to achieve maximum reach in msq-mgl plane

• optimized the cut to general MSSM assumption (massless neutralino)


4 signal regions

1 lepton analysis

• require exactly 1 electron or 1 muon (pT>20GeV)

• 1st jet >60GeV

• 2nd & 3rd jets >30GeV

• further requirements

• Missing ET>125GeV

• MT(lep,EtMiss) > 100GeV

• Meff > 500GeV

• Backgrounds

• easier handle on QCD

• top(single, pair), W +jets dominant

• MC based estimate with normalization to a control region


afte

r le

pton

+je

ts c

ut

results in table


0 lepton

No excess observedprofile likelihood method to compute 95% CL upper limitnon-SM cross sections [pb] A: 1.3 B: 0.35 C: 1.1 D: 0.11

1 lepton

No excess observedprofile likelihood method to compute 95% CL upper limitelectron: 0.065 [pb] (2.2 events) muon: 0.073 [pb] (2.5 events)

interpretation in mSUGRA/CMSSM framework

• not believing in mSUGRA, but it serves as the common ground for comparison across (current/previous) experiments and theories

• equal squak and gluino masses, below 775/700 GeV are excluded with 95% CL for 0/1-lepton mode

• exceed results from the previous (and CMS) experiments


0-lepton analysis

1-lepton analysis

SUSY discovery reach in 2011 and beyond

• empirical rough estimate of the SUSY 5s discovery reach in different and follows


( )

• baseline scenario is 7TeV 1fb-1 in 2011, but 2-3 fb-1 is possible reach (Chamonix 2011)

30.9

???

possible choice in 2012 ??

??

???

ATLAS/CMS excludedATLAS/CMS excluded

Other Exotics Searches


quick glance for search comparisons


ATLAS TEVATRON CMS

excited Q M>1.26TeV (PRL 105, 16180 (2010))dijet mass resonance search (315nb-1)36pb-1 result coming soon

M>0.87TeV M>1.58TeV2.9pb-1

Contact Interaction

L>3.4TeV (PLB694(2011)327)dijet angular distribution (3.1pb-1)36pb-1 result coming soon

L>2.84-3.06TeV L>5.6TeV36pb-1

quantumBlack Holes

36pb-1 result coming soon NONE various limits(35pb-1)

W’ 36pb-1 result coming soon M>1120GeV M>1580GeV(36pb-1)

Z’ 36pb-1 result coming soon M>1071GeV M>1140GeV(35pb-1)

UED 1/R> 728 GeV (arXiv:1012.4272)(3.1pb-1)diphoton + MET

1/R> 477GeV NONE

ATLAS updates (soon) will be better or similar results to CMSexceeded Tevatron limit in the first year, no surprise yet so far

LHC/ATLAS Upgrade Plan


the 10 year technical plan(based on schedule @12.2010)


7-8TeV: 4-8 fb-17-8TeV: 4-8 fb-1

shutdown in 2016 most likely to be delayed (nodecision yet)

13-14TeV:13-14TeV:

13-14TeV: up to 300 fb-113-14TeV: up to 300 fb-1HL-LHCHL-LHC

subject to change by various conditions (physics, machine)

???shutdown (fixed)

3000fb-1 by 2030

2011Jan Chamonix

General idea towards HL-LHC

• [2011-2012] 1st physics results (Higgs 3 coverage, SUSY < 1TeV) will be accomplished with 7TeV, 5-10fb-1

• [by 2020] will cover LHC design goal with 14TeV, a few 100 fb-1

• [post 2020] further pursue: HL-LHC for 3000fb-1

• new physics search: further extension to higher mass scale

• high precision measurements (Higgs couplings, SUSY masses)complementary to ILC

• In any regards, the upgrade is inevitable in both LHC and Detectors

• development for more intense beams

• detectors have to survive the high lumi, and keep (or improve)the performance

• minimize the impact to physics program & maximize the outcome

preparation for upgrade is important whatever the run schedule would be


LHC upgrade for higher intensity[0] LHC injection chain (x2-3 lumi)

[1] new high gradient / large aperture quadruples

• Bpeak = 13-15T, * =55cm 23cm (x2.4lumi w/ CC)

• Nb-Ti (current LHC) would not be safice

• US-LARP (LHC Accelerator Research Program) engaged to demonstration prototype with Nb3Sn by 2013

• KEK-CERN develops Nb3Al technology choice ~2014

[2] RF Crab Cavities

• kick beam sideway to bring the collision head-on

• not yet been validated for LHC (KEKB is the only working proof on earth)


[1]

curr

ent

LHC

new quads

CC

[2]

In both cases, Japan’s Accelerator technologies plays crucial roles: Japan-EU-US design teamhad been established

In both cases, Japan’s Accelerator technologies plays crucial roles: Japan-EU-US design teamhad been established

ATLAS detector upgrade plan

• Major items towards HL-LHC

• ID: replace full ID with silicon only tracker (pixel + short strips + long strips)

• CAL: Endcap electronics, Forward CAL may require upgradesthree upgrade scenarios/development on going

• MUON: replacement of forward tracking MDT

• TRIGGER: upgrade for L1Cal and L1Muon, and combination (e.g. non-Isolated muon)


Commitments/Contributions from ATLAS-JAPAN group

Summary

• LHC 2010 run was successful

• (not shown in detail though) SM measurements/ detector performance were super and more than expected

with 36pb-1

• Higgs: the exclusion limits came close to Tevatron

• SUSY & Exotics : significantly exceeded Tevatron limits

• fruitful results (hopefully with surprises) are promising in 2011-2012 run

• we are getting maximum speed for an efficient genuine collaboration works

• upgrade works for HL-LHC (2020 onward) is under waycomplementary and (good) competitive to ILC


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LHC status and plan

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