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Strategic Overview for Elementary Particle Physics
David B. MacFarlaneAssistant Director for EPP
June 6, 2006
Strategic Overview for Elementary Particle Physics 2
Summary of EPP program elements200620072008200920102011201220132014201520162017201820192020
SiD
Atlas
BABAR
Full EXO
EXO-200
Construction Data taking Ongoing analysisR&D
Strategic Overview for Elementary Particle Physics 3
The BABAR Collaboration
11 Countries 80 Institutions623 Physicists Jawahery, Faccini
Strategic Overview for Elementary Particle Physics 4
Pillars of BABAR physics program
Highly constrained and redundant set of precision tests of weak interactions in the Standard Model
Searches for physics beyond the Standard Model in a well understood & characterized environmento Sensitivity to New Physics at LHC mass scales
through rare decays and CP violationo Discovery potential from large data sample across
a whole range of beauty, charm, tau, two-photon, ISR physics
o Full program of flavor physics/CP violation measurements will provide a legacy of fundamental constraints on future New Physics discoveries
Challenging measurements at the edge of sensitivity benefit enormously from operation of both PEP-II &
KEK B Factories
Strategic Overview for Elementary Particle Physics 5
Integrated data sample to date
Project Run 5at 415 fb-1 delivered
Strategic Overview for Elementary Particle Physics 6
BABAR & Belle physics results
Journal Papers BABAR Belle
Total [Today] 214 172
0
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Belle
BaBar
Strategic Overview for Elementary Particle Physics 7
0 0 0 , , S SCPV in B K K
Interference of suppressed b s Penguin decay with
mixing
CPV in Penguin Modes
0- 0B Bmixing ( )b u
,
)B and ( b c 0,1 0,0
1
2
3
0Bb
db
d t
tWW 0B
0Bs
b
d
W
0Kd
ss
g, ,u c t
0 0 0 0 0 0 00( , , , , , , , )S SB f K K K K K
List of channels continues to expand…
Strategic Overview for Elementary Particle Physics 8
Summary of sin(2) in Penguins
sin
Example from recent calculations (QCD factorization)2-body: [Beneke; PL B620, 143 (2005)]3-body: [Cheng,Chua,Soni; PRD72, 094003 (2005)]
Representative theory estimates
Naïve2 Average: 0.50 ± 0.06 (2.8)
KS
Strategic Overview for Elementary Particle Physics 9
Parameter Units Design Oct 2005 2007 goal
I+ mA 2140 2940 4000
I- mA 750 1740 2200
Number of bunches
1658 1732 1732
by* mm 15-20 11 8-8.5
Bunch length mm 15 11-12 8.5-9
xy 0.030.044-0.065
0.054-0.07
Luminosity x1033 3.0 10.0 20
Int lumi / day pb-1 130 727.8 1300
PEP-II overall parameters and goals
30%
40%
10%
Factor 2!
Seeman
Strategic Overview for Elementary Particle Physics 10
BABAR Detector
DIRC PID)144 quartz
bars11000 PMs
1.5T solenoid
EMC6580 CsI(Tl) crystals
Drift Chamber40 layers
Instrumented Flux Return
Iron / Resistive Plate Chambers or Limited
Streamer Tubes (muon / neutral hadrons)
Silicon Vertex Tracker
5 layers, double sided strips
e
(3.1GeV)
e (9GeV)
Collaboration founded in 1993Detector commissioned in 1999
Strategic Overview for Elementary Particle Physics 11
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Projected data sample growthIn
teg
rate
d L
um
inosit
y [
fb-1]
12
17
20
Lpeak = 9x1033
o PEP-II: IR-2 vacuum, 2xrf stations, BPM work, feedback systems
o BABAR: LST installation
4-month down for LCLS, PEP-II &
BABAR
Double from 2004 to 2006
ICHEP06
Double again from 2006 to
2008 ICHEP08
Strategic Overview for Elementary Particle Physics 12
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How does this compare with KEKB?In
teg
rate
d L
um
inosit
y [
fb-1]
PEP-II (Jun 06)
KEKB no crab effect (my guess)
KEKB from Oide
Strategic Overview for Elementary Particle Physics 13
Errors/LuminosityS Belle BABAR Belle BABAR
Mode S stat err lumi
Untag sample S stat err lumi
Untag sample st*sqrt(L) st*sqrt(L)
Perf Ratio
Lumi Ratio
phiK0 0.440 0.270 357 258 0.500 0.250 205 212 5.101 3.579 1.425 2.031etapK0 0.620 0.120 357 1017 0.270 0.140 205 819 2.267 2.004 1.131 1.279KKK0 0.600 0.180 357 536 0.550 0.170 205 452 3.401 2.434 1.397 1.952KSKSKS 0.580 0.360 357 105 0.630 0.320 205 129 6.802 4.582 1.485 2.204f0K0 0.470 0.360 357 145 0.950 0.320 192 152 6.802 4.434 1.534 2.353pi0K0 0.220 0.470 357 344 0.350 0.300 205 300 8.880 4.295 2.067 4.274ccbarK0 0.652 0.039 357 5264 0.722 0.040 205 10320 0.737 0.573 1.287 1.655pipi -0.670 0.160 253 666 -0.300 0.170 205 467 2.545 2.434 1.046 1.093rhopi S -0.280 0.230 140 483 -0.100 0.140 192 1184 2.721 1.940 1.403 1.968rhopi A+- -0.020 0.160 140 483 -0.210 0.110 192 1184 1.893 1.524 1.242 1.543rhopi A-+ -0.530 0.290 140 483 -0.470 0.140 192 1184 3.431 1.940 1.769 3.129rhorho 0.090 0.420 253 142 -0.330 0.240 205 617 6.681 3.436 1.944 3.780Averages 1.477 2.272
Typically better errors for BABAR despite larger Belle
dataset
Normalized performance
ratio
Updated performance comparisonRevised from 2005 results; conclusions unchanged from 2004 study
Strategic Overview for Elementary Particle Physics 14
Present and future CKM physics
sin2
2008: ~2% 2008: 10o
2008: 5-10o
ubV
2008: ~5%
B
2008: New CKM constraint & new
physics limits
B
Strategic Overview for Elementary Particle Physics 15
Global CKM fit: 2008
( ) 5.0%ubV ( ) 1%sm (sin 2 ) 0.019 o( ) 8 o( ) 10
95% contours
Strategic Overview for Elementary Particle Physics 16
BABAR summary
Highest priority SLAC program with goal of 1 ab-1 or 109 BB pairs by Sep 2008o Remaining hardware upgrades to be completed in 2006o Performance and operational challenges of 2x1034 well
understood and in hando Computing and physics analysis framework mature &
scalableo Computing hardware needs being addressed across a set of
Tier A centers Physics opportunities remain exciting &
competitiveo New ideas continue to be invented; factors of two in sample
size do matter, as new thresholds are reached in sensitivityo Possible hints for new physics in penguin modes will be
addressed with the 1 ab-1 sampleo Precision flavor physics results will in any event represent a
significant constraint on new physics in the era of the LHC
Strategic Overview for Elementary Particle Physics 17
Physics opportunities
Goal for 2005-2006: double current data seto Delay in Run 5 can be overcome by summer 2006 with
extended running period, with substantial reduction in errors on CP violation asymmetries in rare decay modes
o Error on average of Penguin modes should reach 0.06 Goal for 2007-2008: double again to ~1 ab-1
o Individual Penguin modes with errors in range 0.06-0.12o Suite of fundamental Standard Model measurements with
substantially improved levels of precision
Program will continue to be exciting and competitive through at least 2008
o Sensitivity to New Physics through rare decays, CP violation, & large data sample with a significant discovery potential
o Full program of flavor physics/CP violation measurements provide fundamental constraints on future New Physics discoveries
Strategic Overview for Elementary Particle Physics 18
A concept for a 1036 Super B Factory?
Positrons
Electrons
Gun
3 GeV 3 GeV
Dump
5 GeV
1 GeVDR
Transport
E+ source
Make up E
Raimondi, Seeman
IP
Strong physics case for a 1036
facility
o Machine has significant technical overlap with ILC, including damping rings, acceleration sections, and final focus
o Appears to be possible to reach 1036 with substantially smaller backgrounds, allowing (re-)use of existing detectors
Strategic Overview for Elementary Particle Physics 19
Possible element in alternative scenarios200620072008200920102011201220132014201520162017201820192020
Delayed SiD
Atlas
BABAR
Full EXO
EXO-200
Construction Data taking Ongoing analysisR&D
Offshore Super B
LHC Upgrades
Strategic Overview for Elementary Particle Physics 20SLAC participation in SLAC participation in AtlasAtlas
Su Dong
Strategic Overview for Elementary Particle Physics 21
Arguments for SLAC entry into Atlas
o Allows exploitation of the physics synergy between LHC and ILC at the energy frontier
• Direct involvement in both is best path to gaining a first-hand understanding of the full physics opportunity
• ILC approval is now also tied to the initial outcome of LHC and its potential for new physics discovery
o Responds to the needs of our user communityo Experience in the operation of a new energy frontier facility
by large collaborations is directly relevant for LCDo With completion of BABAR data taking in 2008 &
construction approval of ILC in 2010 or beyond, there will be a significant gap of >7 years in our accelerator-based HEP program.
• Joining LHC an obvious way of maintaining & developing a healthy work force for ILC, by continuing to attract the best young people to SLAC
Strategic Overview for Elementary Particle Physics 22
SLAC areas of involvement
With advice from ATLAS and US ATLAS managements, and many ATLAS US/Atlas users, identified 4 related areas of initial contribution:
o Pixel detector commissioning and calibration, based on experience at Mark II, SLD, & BABAR
o Higher level trigger, building on extensive SLD & BABAR expertise
o Core and Atlas-specific GEANT4 simulation o Tier 2 computing center & eventually a west-coast physics center
in partnership with LBNL, UCSC, and the larger Atlas user community
Roles are connected to each other, to our physics interests, and to our user community
Consistent with likely roles on ILC detector as wellAll areas with unique strengths at SLAC matched to a national
laboratory role
Strategic Overview for Elementary Particle Physics 23
Western Tier 2 center proposal Proposing to be a premier Tier 2 center = simulation,
calibration & detector studies, and physics analysis o Good data access and strong technical support is crucial for
analysiso Proposal supported and developed in conjunction with LBNL,
Arizona, UCSC, UCI, Oregon, Wisconsin Madison, & Washington Will leverage existing & planned investments for BABAR
o Investment level about 25% of typical BABAR computing needso Proven management tools and scalable infrastructureo “Lights out” no operator 24x7 operation for last 10 yearso Common CPU pool with BABAR can benefit both experiments by
exploiting staggered peak usageo One incremental FTE systems/operations support person from Tier
A; remainder of support directed to hardware purchases SLAC, in partnership with LBNL & UCSC, will help support
a vibrant west coast center for physics on Atlaso Many common interests in Atlas: pixel and inner detector
tracking/alignment, trigger and event simulation, & physics analysiso User facilities exist to house many visitors on siteo New mode for HEP that we are keen to develop with our users
Strategic Overview for Elementary Particle Physics 24
Very active HEP theory group
Broad range of research pursuedo Strings: Silverstein, Kachruo Collider Phenomenology: Dixon, Hewett, Peskino B phenomenology: Quinno Hadron physics: Brodskyo Assistant Prof offer pending – model buildingo Possible additional appointment in next 5 years, along with
additional KIPAC/theory billets Well aligned with existing and future
experimental programso Have taken an important role in developing Atlas participationo Will provide leadership in West Coast Atlas physics effort
centered at SLAC Active postdoc program attracting top
candidateso Vibrant element of SLAC’s particle physics community
Peskin
Strategic Overview for Elementary Particle Physics 25
ILC Detector
ILCILC DetectorDetectorILC ILC
DetectorDetector
Jaros, Raubenheimer
Strategic Overview for Elementary Particle Physics 26
LCD overall strategy
Factors driving development timelineo Technical requirements require significant large-scale R&D
to realize beyond state-of-the-art performance, e.g., from particle-flow calorimetry
o GDE pursues an aggressive TDR goal by 2009o Scale of European R&D effort significantly larger: Need to
increase US effort to maintain intellectual leadership consistent with EPP2010 report
Strive to develop coherent detector design SiD with US and international partnerso Allows exploration of overall constraints and optimization o Key element is particle-flow calorimetry, requiring dense,
highly segmented SiW electromagnetic and hadronic calorimetry
o Large magnetic field, compact tracking follow from cost considerations
30%/ E
Strategic Overview for Elementary Particle Physics 27
SLAC leading Silicon Detector Design Study
o Providing Computing/Simulation infrastructure for all SiD
o Engaging collaborators at Fermilab, BNL, Argonne, many US Universities. Developing international ties (KEK, Tokyo, Annecy, Oxford)
o Coordinating & pursuing detector R&D
Si/W calorimetry and KPiX ASIC
Tracker design/Si microstrips CMOS pixels for vertex
detectoro Optimizing & benchmarking SiD
Design SiD detector outline document completed with
130 authors
Strategic Overview for Elementary Particle Physics 28
Ongoing R&D goals for SiD at SLAC
Ecalo KPiX, new Si sensors, prototype, beam test, mechanical design,
proof of principle
Main Trackero Tracker Si sensor, prototype sensor modules, beam test
Vertex Trackero Evaluate performance, mechanical design (with FNAL), develop
sensor
Reconstruction Codeo Perfect particle-flow algorithm, tracking pattern recognition
Benchmarking/Analysis/Design Optimizationo Detector performance requirements, new physics analyses,
global optimization, subsystem optimization
Strategic Overview for Elementary Particle Physics 29
Expanding Effort on SiD
Present program is too small to maintain ambitious ILC timeline and leading role for US community
o Initial startup of SLAC/Atlas effort presents near-term challenges for SiD effort, although symbiosis very healthy long-term
New SiD personnel allow us to mount ambitious program
o Mechanical engineer, mechanical technician, computer support, postdoctoral researchers, simulation physicist, visitors
New SiD Si lab space tentatively identifiedo KPiX development, Sensor development
Additional SiD M&S would support proof of principle R&D as a key factor in overall design
o PFA and high-performance calorimetry; compact silicon design SLAC is a natural site to lead an ILC detector
development effort with our user communityo Engineering, construction facilities, computing & simulation
infrastructure, test beams, a center for design and analysis activity, & established key areas of expertise
Strategic Overview for Elementary Particle Physics 30
SiD timeline200620072008200920102011201220132014201520162017201820192020
SiD
Construction Data taking Ongoing analysisR&D
Strategic Overview for Elementary Particle Physics 31
EXO: Enriched EXO: Enriched Xenon ObservatoryXenon Observatory
Rowson
Strategic Overview for Elementary Particle Physics 32
normalhierarchy
invertedhierarchy
Most important questions in neutrino physics
o Neutrino flavor oscillations imply the neutrino has a finite mass, but do not give an absolute mass scale: what is the neutrino mass scale?
o Are neutrinos are their own antiparticles (Majorana)?
Allowed hierarchy of mass differences and mixing
angles
2 process occurs in the Standard model0 process only proceeds if ’s are their own antiparticles (Majorana) and massive
For 0 decay, the rate ~ <m> 2.
~(1 – 4) meV normal hierarchy
~(15-60) meV inverted hierarchy
Strategic Overview for Elementary Particle Physics 33
EXO experimental strategy
Detect Standard Model 2 double beta decayso Use (liquid) xenon as source and detectoro Xe136 is a relatively easy isotope to enrich – and – EXO has 200 Kg
on campus!! Developing background free next generation
experimento Rejecting 2 neutrino decay backgrounds:
• Energy resolution in TPC using ionization and scintillation lighto Rejecting external backgrounds:
• Use radiologically quiet materials to build and shield apparatus• Locate apparatus in radiologically quiet area = deep
underground salt deposit at WIPPo Turn experiment into coincidence experiment by detecting nuclear
daughter of double beta decay of Xe136 to Ba136 (one single ion at a time!) Unique feature of EXO 136 136Xe Ba e e
Identify event-by-event
Strategic Overview for Elementary Particle Physics 34
EXO-200 will use 200 kg of 80% enriched Xe136; it will not employ barium ion tagging.
The goals of the EXO-200 program are :
o Test the LXe TPC operation : energy and spatial resolution, chemical purity issues, mechanical design and all backgrounds due to radioactivity and cosmic radiation.
o Observe 2 decay in Xe136 for the first time and measure the rate of this important 0 background.
o Confirm or refute the controversial claim of Klapdor et al. (Observation of 0 in Ge76 → a mass of ~0.4 eV).
EXO-200 project
Develop barium extraction and detection in a parallel R&D program
Strategic Overview for Elementary Particle Physics 35
Full EXO neutrino mass sensitivity
Strategic Overview for Elementary Particle Physics 36
EXO timeline200620072008200920102011201220132014201520162017201820192020
EXO-200
Construction Data taking Ongoing analysisR&D
Full EXO
Strategic Overview for Elementary Particle Physics 37
Summary of EPP program elements200620072008200920102011201220132014201520162017201820192020
SiD
Atlas
BABAR
Full EXO
EXO-200
Construction Data taking Ongoing analysisR&D
Strategic Overview for Elementary Particle Physics 38
Summary of EPP program
An array of fundamental physics questions challenge our understanding of nature and the universe
o EPP2010 maps out a strategy of leadership for the US program in addressing these questions
o Central elements of this strategy are:• Full exploitation of the LHC• Development and eventually hosting of the ILC in the US• Pursuit of astroparticle experiments, a new round of coordinated
neutrino experiments, and further exploration of precision flavor physics
SLAC EPP program is well aligned with these prioritieso Actively planning a transition from onsite accelerator-based frontier
research at BABAR to a portfolio involving major contributions to the international program at Atlas, SiD, and EXO, or potentially elsewhere
o Science has and will continue to be the driver for this program, with SLAC continuing its role a strong partner and national user facility