Transcript Pre-assembly schedule. Barrel assembly schedule

The ATLAS Physics Program
JINR participation,
achievements,
short- and long-term plans
Diameter
25 m
Barrel toroid length
26 m
End-cap end-wall chamber span 46 m
Overall weight
7000 Tons
Bednyakov
V.A., HS07
В.Бедняков, 13 июня 2007, ЛВЭ
Collisions at the LHC
Slide by T. Virdee
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An Aerial View of Point-1
(Across the street from the CERN main entrance)
В.Бедняков, 13 июня 2007, ЛВЭ
The Underground Cavern at Pit-1 for
the ATLAS Detector
В.Бедняков, 13 июня 2007, ЛВЭ
JINR ATLAS History
The proposal on the participation of
the JINR team in ATLAS was firstly
presented in 1995. The PAC
recommended this project for
approval on 24 November 1995.
Further on status reports on this
projects have been regularly (yearly)
presented at PAC and JINR
Scientific Council meetings.
In 1995, 6567 kUSD+140 kHours
of workshop were requested,
including 4069 kUSD from the
JINR budget
В.Бедняков, 13 июня 2007, ЛВЭ
The ATLAS detector
Over the last decade JINRATLAS team was deeply involved
in designing, construction, tests
and assembly of the major
systems of ATLAS:
Inner Detector
Tile Calorimeter
Liquid Argon End Cap Calorimeter
Muon detector
Common Items (Toroid Warm
Structure and others)
Participation in the Physics Program was always considered as the most important
target. Till 2003 this work has been performed mainly in “background” regime,
essentially based on individual efforts, promoted with limited resources case-by-case
(as well as for software developments and general computing infrastructure of
ATLAS).
В.Бедняков, 13 июня 2007, ЛВЭ
ATLAS costs:
15 x 12 x 100 x 6000 = 1.08 108 CHF
В.Бедняков, 13 июня 2007, ЛВЭ
JINR Workshops on the ATLAS Physics

Early 2004 the JINR-ATLAS team management decided to
establish a regular framework (series of workshops) to
promote physics-oriented activities at home, aimed to:
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Open the door for new ideas (also attract new collaborators,
interested in future physics at LHC);
Monitoring of ongoing activities and select most promising ones
to provide the necessary support, in particular for visiting
conferences and dedicated ATLAS meetings;
Enrich “home community” by involving physicists from JINR
member countries who have less possibilities in computing and
networking, to make JINR-ATLAS resources and experience
widely available;
Keep people informed about recent software developments and
dedicated computing infrastructure at JINR.
Web site:
http://www.atlas-jinr.ru/
В.Бедняков, 13 июня 2007, ЛВЭ
Main ATLAS Physical topics
Standard Model Physics
 Higgs Boson Physics
 SUSY Physics
 Exotics Physics
 Top Quark Physics
 Heavy Ions Physics
 B Physics

В.Бедняков, 13 июня 2007, ЛВЭ
JINR ATLAS Physics team
What we are doing
В.Бедняков, 13 июня 2007, ЛВЭ
SANC
Project SANC (Support of Analytical and Numerical Calculations
for Experiments at Colliders). http://brg.jinr.ru/
D.Bardin, L.Kalinovskaya, P.Christova, et al (DLNP, JINR),
A.Arbuzov, S.Bondarenko (BLTP, JINR).
This very ambitious project starts to produce applications (generators, etc)
which allow investigations of prospects for observation of the
physical phenomena at the LHC with ATLAS detector.
В.Бедняков, 13 июня 2007, ЛВЭ
SANC
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SANC, 2007
В.Бедняков, 13 июня 2007, ЛВЭ
Higgs boson(s)
Search for the SM Higgs boson via decay H→4μ.
Full ATLAS simulation, etc.
G.Chelkov, I.Boyko, K.Nikolaev, et al
Search for Higgs boson with mass 115-160 GeV by means
of decay H->Z+gamma and Z->2l within ATLAS software
APHENA. (Usubov et al).
Search for Higgs boson (400-1000 GeV) decaying H->ZZ->lljj
and being produced via vector boson fusion (Usubov,
Kultchitski, et al).
Seach for charged Higgs boson via tau-nu_tau decay (Chelkov, et al.)
Study of associative production of Higgs boson and top-antitop pair .
В.Бедняков, 13 июня 2007, ЛВЭ
15
Higgs boson(s)
JINR
В.Бедняков, 13 июня 2007, ЛВЭ
Higgs boson(s)
Search for the SM Higgs boson via decay H→4μ.
Full ATLAS simulation. G.Chelkov, I.Boyko, K.Nikolaev, et al
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SIGNAL: At CERN with SANC generator (with 1-loop corrections and quantum
effects of final state muon identity, for the 1st time) 30 000 H→  decays
were generated for MH=130, 160 GeV/c2. For comparison 10 000 H→ 4 decays
were generated with PYTHIA.
BACKGROUND: With PYTHIA (and ACERMC) generators 30 000 background
events for pp→ZZ, pp→Zbb, with 4 final state muons were simulated. Single Z
boson coincidence events “Z+Z” were also simulated. Almost all background
events (1/3 of all data) were simulated at LIT farm in Dubna, where modern (the
latest versions) ATLAS software are installed.
Detector simulation and event reconstruction were carried out completely
within modern ALTAS software (C++, ATHENA, GEANT-4, AOD, Root). The
results were compared with results obtained earlier (with Fortran, ATLSIM,
GEANT-3, HBOOK). CERN and Dubna events (signal and background) were
developed in the same manner. The CERN and Dubna simulation and analysis
gave almost the same results.
В.Бедняков, 13 июня 2007, ЛВЭ
Higgs boson, H→4μ
Reconstructed events
130 GeV
160 GeV
В.Бедняков, 13 июня 2007, ЛВЭ
Higgs boson, H→4μ
Generator SANC predicts higher than PYTHIA number of
selected decays H→ (about 10-15%). There are two
reasons: a higher selection efficiency and larger predicted
width of the decay.
The “golden channel” H4leptons is one of
the most promissing for the early discovery.
For the light Higgs (120-160 GeV) the signal
is low (tens events per year), but the selection
efficiency is high and the background is almost
zero.
The full simulation study shows that H4μ
alone ensures a ~5σ discovery after one year of
nominal luminosity.
В.Бедняков, 13 июня 2007, ЛВЭ
Higgs boson(s)
to search for Higgs decay
В.Бедняков, 13 июня 2007, ЛВЭ
Higgs boson, H→Zγ, etc
Search for Higgs boson with mass 115-160 GeV by means of decay
H->Z+gamma and Z->2l within ATLAS software APHENA. (Usubov et al).
to be completed in 2007
В.Бедняков, 13 июня 2007, ЛВЭ
Higgs boson(s)
1) Search for Higgs boson with mass 115-160 GeV/c by means of associative
production of Higgs and Gauge Bosons (pp→W(Z)+H+X) and Higgs decay
into bb-pair (H→2b→2b-jets).
2) Study the ATLAS large-mass Higgs discovery potential by means of
reactions H→2W→2lν, H→2W→lνjj and H→2Z→2lν, H→2Z→lljj.
Proposals rely on the Higgs boson production via the Vector Boson Fusion
mechanism (the two accompanying forward jets allow very good background
reduction) and on the maximal Higgs decay rates into WW- or ZZ-pair at
M=400—1000 GeV.
One needs a Higgs Coherence !
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What IS this Higgs Coherence?
Higgs boson main decay channels (in SM and beyond):
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H
HWW*
H
H4leptons
pp  ttH+X, Hbb, 
+ Higgs properties (self couplings) …
Our potential important task is to check – How the
Higgs boson decaying, for example, into 4 muons
“shows” itself in the other allowed decays (into 2
photons, bb-pair, etc)?
One needs this for the cross-check and the SM EWSB:
Is this Higgs the same one, or some another one?
В.Бедняков, 13 июня 2007, ЛВЭ
Top quark physics
Verification of the top-quark charge (is it +2/3 or -4/3 ?):
ATLAS will be able to verify top quark charge after
analyzing of data taken 1-2 weeks of LHC operation.
Search for narrow neutral resonance state (like Z‘ boson)
decaying into the top-antitop pairs on the basis of ATLAS
top WG data challenge (Khramov, Tonojan. Bednyakov,
Rusakovich).
Accurate investigation of single top quark production at
LHC (in the SANC framework by Bardin et al.)
Study of associative production of Higgs boson and top-antitop pair .
В.Бедняков, 13 июня 2007, ЛВЭ
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Top quark physics
Verification of the of the top-quark charge (is it +2/3 ?):
ATLAS will be able to verify top quark charge after
analyzing of data taken 1-2 weeks of LHC operation
Top quark charge measurement
via determination of its decay
products charges
(Full & Fast Simulation)
V. Bednyakov, E. Khramov, N. Rusakovich, A. Tonoyan
(JINR, Dubna, Russia)
A. Tonoyan
ATLAS-JINR Physics Workshop
14 April 2006
The work was
presented at ATLAS
Top WG Meeting
(23 March 2006).
The article was
submitted to ATLAS
Notes.
1
В.Бедняков, 13 июня 2007, ЛВЭ
Top quark physics
Search for tt resonances at
the ATLAS (FullSim)
E. Khramov, V. Bednyakov, N. Rusakovich, A. Tonoyan
E. Khramov
ATLAS-JINR Workshop, 22 Dec 2006
5σ discovery level
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1
Higgs boson, pp→Htt, etc
Started search for Higgs boson production together
with top-antitop pair pp→Htt (within ATLAS software
by Akhmedov, Zorin and Titkova).
Higgs boson mass reconstruction via electron-positron
pair within EventView software and Root 5.14
was performed.
В.Бедняков, 13 июня 2007, ЛВЭ
Exotics, Spin-2 gravitons (EDs)
The search for and identification of the graviton-like Kaluza-Klein states in
the lepton-pair production at LHC via new CENTER-EDGE ASYMMETRY
was proposed by A.Pankov (Gomel).
The A_CE allows isolation of
spin-2 graviton contribution - unique graviton exchange
signature.
PYTHIA+ADD
Centre-edge asymmetry in the ADD
and RS scenarios in lepton pair
production at LHC energies
V.A. Bednyakov, A.A. Pankov, Inna Serenkova, N.A. Rusakovich
LNP, JINR, Dubna
&
Gomel State University
&
ICTP Affiliated Centre at the Technical University of Gomel
ATLAS-JINR Physics Workshop
14.04.2006
1
В.Бедняков, 13 июня 2007, ЛВЭ
Exotics, LFV
Study of rare LFV tau
decays in ATLAS: τ  μμμ
and τ  μγ
Sources of  leptons at LHC
Proposal for search of
τ  μμμ
@ ATLAS
1 year of low luminosity = 10 fb-1
V.Zhuravlov
NEOVP-ATLAS
December 22, 2006
JINR ATLAS meeting
V.Zhuravlov et al
1
ATLAS sensitivity is about
10-8 for τ  μμμ
(better x10 of current limit)
10-7 for τ  μγ
pp W   n
s = 19 nb
19108 
pp  Z   
s = 3 nb
3 108  
pp  BB  
Dn
s = 24 b
2.41011 
В.Бедняков, 13 июня 2007, ЛВЭ
Exotics, Monopol
Two-photon production and detection of the
monopole-antimonopole pairs at LHC
Yu. Kurochkin, I.Satsunkevich, D. Shuolkavy, S. Yanush (Minsk),
V. Kukhtin, Yu. Kultchitski et al (JINR)
pp    X  M  M  X
Large ionization, like nucleus with Z=70
Some remarks about
magnetic monopoles at
ATLAS
I.S.Satsunkevich
Дубна, 22.12.2006
В.Бедняков, 13 июня 2007, ЛВЭ
Search for gluinos with ATLAS
g + g → gluino + gluino
SIGNATURE:
4 b-jets + 4 muons + Etmiss
1 pb
m0 = 1400 GeV
m1/2 = 180 GeV
A = 0
sign(μ) = +1
tanβ = 30
Pythia within ATHENA,
B-vertex taging
LARGE!
Almost
background-less
150 events/year
В.Бедняков, 13 июня 2007, ЛВЭ
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SUSY, Gluinos
Search for SUSY at ATLAS with leptons
V.Bednyakov, Y.Budagov, A.Gladyshev, D.Kazakov, J.Khubua, E. Khramov
В.Бедняков, 13 июня 2007, ЛВЭ
SUSY, Gluinos
Gluinos can be observed and
SUSY parameters m1/2
can be separated
m1/2=170 GeV m1/2=180 GeV m1/2=190 GeV
total events
88380
63630
43200
di-lepton
1057
681
529
lepton+jets
17040
12339
8104
В.Бедняков, 13 июня 2007, ЛВЭ
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SUSY
1. Study (full simulation) of prospects for registration (with ATLAS) the SUSY gluinos (at
very specific and very promising EGRET MSSM region) by means of two main gluino
decay channels (4b-quarks+4leptons+E_missing and 4b-quarks+2jets+2leptonsE_missing).
2. Search for and investigation of (via fast and full detector simulations) all possible
background processes (QCD, qq(gg)->4b+2l+2q, etc) for the above-mentioned SUSY
process. Study of influence of relevant miss-tagging of b-jets and muons.
3. Study of prospects of registration of “weak SUSY” processes at the same EGRET
MSSM region (complimentary to the above-mentioned gluino production). In these
processes one expects, for example, 3leptons+neutrino+E_missing (due to the two
lightest neutralinos which escape detection) and one isolated lepton (or jet)
accompanied by (very) large missed “transverse” energy (due to W boson decay into
neutraino and charghino). Both (gluino and “weak”) investigations are very important for
the coherent SUSY search strategy.
(E.Khramov, V.Bednyakov, Yu.Budagov, A.Gladyshev, D.Kazakov, J.Khubua, S.Karpov,
I.Titkova + students+ CERN colleagues)
В.Бедняков, 13 июня 2007, ЛВЭ
SUSY Exotics
Study of R-hadrons detection
possibility with ATLAS
V.Smakova, G.Chelkov, R.Leitner
Study of R-hadrons
detection possibility at
ATLAS
Big mass >100 GeV
R-hadron -- passive gluino
+ interacting π/ρ/K/p/n cloud
In a nuclear interaction, they may flip
charge and baryon number.
01.09.2007
Signatures:
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В. Шмакова
High transverse momentum for charged hadrons
Heavy ionization in the tracking system
Missing transverse energy due to large R-hadron mass
“Small” E/p distribution
Large time-of-flight, measurable with the muon chambers and TileCal
В.Бедняков, 13 июня 2007, ЛВЭ
1
Heavy Ions
Jet quenching is one of the probe of the
Condensed Nuclear Matter (QG-Plasma)
Full ATLAS simulation of Z0->- in pp-,HI
production is carried out. Point-like Z0 production is
not influenced by QGP, so the study of jet quenching
provided by Z0. One month HI running gives 5000
Z0 in the muon mode. The usage of this mode is
helpful in study of jet quenching.Back-to-back
configuration of Z0+jet event is tool for the jet
reconstruction.
V.Pozdnyakov+
ffbara*/Z0
 and (Z0 +jet) in HI
CONTENT:
•  collisions and observables
• muon and electron pairs
• high pT jets
• open charm
• (Z0 +jet) and an effect of jet quenching
• jets of interest egenerator (HIJING)
• high pT Z0 and jets
SUMMARY
JIN
R
/ A
TL
A
Sm
eet
V.Pozdnyakov
Z reconstruction
22.12.06
В.Бедняков, 13 июня 2007, ЛВЭ
Quark-gluon structure functions
The possibilities of measuring at the LHC
the gluon distributions in the proton by
means of simultaneous registration of the
direct photons (Z-bosons) and jets
("gamma/Z+jet" events)
Investigation (within SANC) of possibility to
apply an accurate Drell-Yan calculations for
LHC luminosity monitoring and PartonDistribution-Function measurements.
Development of a new generator for PDFs which obey QCD
evolution equations at very low Feynman x and study of their
influence on the cross sections of the basic LHC processes
(by A.Kotikov, D. and V. Peshekhonov).
PDF monitoring via D- or B-meson yields (Lykasov)?
В.Бедняков, 13 июня 2007, ЛВЭ
Standard Model, Drell-Yan
P.Starovoitov et al (Minsk) have considered two-photon
mechanism of Drell-Yan lepton pair production in pp-collisions
Two-photon creation of lepton pairs in pp-collisions
N. Shumeiko, A. Soroko, P. Starovoitov
The two-photon
contribution is
not negligible!
We study another
possibility to
produce lepton
pairs in hadron
collisions, namely,
the two-photon
exchange
В.Бедняков, 13 июня 2007, ЛВЭ
Study of Drell-Yan processes in ATLAS
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Precision calculations of the DrellYan process are carried out (SANC
project)
 From SM Lagrangian to event
distributions
 Including EW and QCD NLO
corrections
 Participating in the international
group (Les Houche and
TEV4LHC workshops
At the same time, the experimental
study of the process is prepared
usinig full ATLAS
simulation/reconstruction
The results show that already with a
decent LHC luminosity the crosssection can be measured with
precision about 1%
Reconstructed invariant mass
of Z→μμ (1 year of LHC run)
В.Бедняков, 13 июня 2007, ЛВЭ
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Standard Model, applications
В.Бедняков, 13 июня 2007, ЛВЭ
Some short-term plans
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Top-quark Physics
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Heavy Ions Physics
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Can be done rather quickly
Important test of SM (charge, mass, etc)
Background for SUSY, Exotics, etc
Energy calibration via Z,W and top, etc
Is the Top “the same” in all ”top” observables?
QGP jet quenching via Z-jet events, γ-γ physics
Standard Model Physics
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Parton DF verification in 2-jet events, B-mesons
Two-photon Drell-Yan processes
Gamma/Z-jet events and Gluon DF
W, Z – properties, etc
В.Бедняков, 13 июня 2007, ЛВЭ
Some long-term plans
Higgs Physics
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H→4μ,
H→bb, H→, H→Zγ, All other Higgs decay channels
SUSY Physics
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How “the first observed” SUSY-particle shows itself in the
other SUSY-channels? (Coherence)
SUSY is background for SUSY
Stop, Gluinos, Same-sign dileptons
Charged Higgs-boson
SUSY Dark Matter Search with ATLAS, etc
Exotics Physics
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SUSY R-hadrons (Travel ATLAS without decays)
SUSY long-living Staus, Stops, etc
Graviton (Spin=2) via Asymmetry_CE and via resonances
Monopoles, etc
Rare tau-lepton decays
В.Бедняков, 13 июня 2007, ЛВЭ
Preparation for the ATLAS data
analysis at JINR
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Since January 2007 JINR site is successfully integrated in the ATLAS DDM
(Distributed Data Management system) Training of use of distributed analysis
tools (GANGA) is ongoing. Recent versions of ATLAS software are installed
at JINR (11.0.41, 12.0.31, 12.0.6, 12.5.0)
19.04.2007 the Tutorial on ATLAS Grid tools and distributed data analysis
took place at JINR – the premier in Russian ATLAS Tier-2!
Russian and JINR
physicists participants
of ATLAS experiment
train and practise with
Grid and the GANGA
В.Бедняков, 13 июня 2007, ЛВЭ
Conclusions
We have enough attractive ideas in the ATLAS research program.
Some of above proposals (Higgs, Top) have already passed
experimental procedure of simulations, background estimates and
reconstructions in the ATLAS. With these tools we are ready to meet
the first real data from the LHC.
Have ATLAS software installed at JINR
Have GRID and have participated in the Data Generation
Have clear short- and long-term plans
Have contacts with Russian ATLAS community
Have fruitfully working JINR-ATLAS-Physics Workshops and still
invite the other Dubna-LHC groups (CMS, ALICE) to join us. Despite
of some differences (detector particularities and software used) we
all could get a lot of benefit from mutual discussions.
My urgent goals: DATA access, ATLAS soft at JINR, Early Physics
В.Бедняков, 13 июня 2007, ЛВЭ