Strategic Overview for Elementary Particle Physics David B. MacFarlane Assistant Director for EPP June 6, 2006

Strategic Overview for Elementary Particle Physics2 Summary of EPP program elements SiD Atlas BABAR Full EXO EXO-200 Construction Data takingOngoing analysis R&D

Strategic Overview for Elementary Particle Physics3 The BABAR Collaboration 11 Countries 80 Institutions 623 Physicists Jawahery, Faccini

Strategic Overview for Elementary Particle Physics4 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 environment oSensitivity to New Physics at LHC mass scales through rare decays and CP violation oDiscovery potential from large data sample across a whole range of beauty, charm, tau, two-photon, ISR physics oFull 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 Physics5 Integrated data sample to date Project Run 5 at 415 fb -1 delivered

Strategic Overview for Elementary Particle Physics6 BABAR & Belle physics results Journal PapersBABARBelle Total [Today]214172

Strategic Overview for Elementary Particle Physics7 Interference of suppressed b  s Penguin decay with mixing CPV in Penguin Modes List of channels continues to expand…

Strategic Overview for Elementary Particle Physics8 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, (2005)] Representative theory estimates Naïve 2 Average: 0.50 ± 0.06 (2.8  ) KSKS

Strategic Overview for Elementary Particle Physics9 ParameterUnitsDesignOct goal I+mA I-mA Number of bunches by*by*mm Bunch lengthmm xyxy Luminosityx Int lumi / daypb PEP-II overall parameters and goals 30% 40% 10% Factor 2! Seeman

Strategic Overview for Elementary Particle Physics10 BABAR Detector DIRC  PID) 144 quartz bars PMs 1.5T solenoid EMC 6580 CsI(Tl) crystals Drift Chamber 40 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 1993 Detector commissioned in 1999

Strategic Overview for Elementary Particle Physics11 Projected data sample growth Integrated Luminosity [fb -1 ] L peak = 9x10 33 oPEP-II: IR-2 vacuum, 2xrf stations, BPM work, feedback systems oBABAR: 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 Physics12 How does this compare with KEKB? Integrated Luminosity [fb -1 ] PEP-II (Jun 06) KEKB no crab effect (my guess) KEKB from Oide

Strategic Overview for Elementary Particle Physics13 Typically better errors for B A B AR despite larger Belle dataset Normalized performance ratio Updated performance comparison Revised from 2005 results; conclusions unchanged from 2004 study

Strategic Overview for Elementary Particle Physics14 Present and future CKM physics 2008: ~2%2008: 10 o 2008: 5-10 o 2008: ~5% 2008: New CKM constraint & new physics limits

Strategic Overview for Elementary Particle Physics15 Global CKM fit: % contours

Strategic Overview for Elementary Particle Physics16 BABAR summary  Highest priority SLAC program with goal of 1 ab -1 or 10 9 BB pairs by Sep 2008 o Remaining hardware upgrades to be completed in 2006 o Performance and operational challenges of 2x10 34 well understood and in hand o Computing and physics analysis framework mature & scalable o Computing hardware needs being addressed across a set of Tier A centers  Physics opportunities remain exciting & competitive o New ideas continue to be invented; factors of two in sample size do matter, as new thresholds are reached in sensitivity o Possible hints for new physics in penguin modes will be addressed with the 1 ab -1 sample o 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 Physics17 Physics opportunities  Goal for : double current data set o 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 : double again to ~1 ab -1 o Individual Penguin modes with errors in range o Suite of fundamental Standard Model measurements with substantially improved levels of precision  Program will continue to be exciting and competitive through at least 2008 oSensitivity to New Physics through rare decays, CP violation, & large data sample with a significant discovery potential oFull program of flavor physics/CP violation measurements provide fundamental constraints on future New Physics discoveries

Strategic Overview for Elementary Particle Physics18 A concept for a Super B Factory? Positrons Electrons Gun 3 GeV Dump 5 GeV 1 GeV DR Transport E+ source Make up  E Raimondi, Seeman IP Strong physics case for a facility oMachine has significant technical overlap with ILC, including damping rings, acceleration sections, and final focus oAppears to be possible to reach with substantially smaller backgrounds, allowing (re-)use of existing detectors

Strategic Overview for Elementary Particle Physics19 Possible element in alternative scenarios Delayed SiD Atlas BABAR Full EXO EXO-200 Construction Data takingOngoing analysis R&D Offshore Super B LHC Upgrades

Strategic Overview for Elementary Particle Physics20 SLAC participation in Atlas Su Dong

Strategic Overview for Elementary Particle Physics21 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 community o Experience in the operation of a new energy frontier facility by large collaborations is directly relevant for LCD o 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 Physics22 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 well All areas with unique strengths at SLAC matched to a national laboratory role

Strategic Overview for Elementary Particle Physics23 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 analysis o 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 needs o Proven management tools and scalable infrastructure o “Lights out” no operator 24x7 operation for last 10 years o Common CPU pool with BABAR can benefit both experiments by exploiting staggered peak usage o 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 Atlas o Many common interests in Atlas: pixel and inner detector tracking/alignment, trigger and event simulation, & physics analysis o User facilities exist to house many visitors on site o New mode for HEP that we are keen to develop with our users

Strategic Overview for Elementary Particle Physics24 Very active HEP theory group  Broad range of research pursued o Strings: Silverstein, Kachru o Collider Phenomenology: Dixon, Hewett, Peskin o B phenomenology: Quinn o Hadron physics: Brodsky o Assistant Prof offer pending – model building o Possible additional appointment in next 5 years, along with additional KIPAC/theory billets  Well aligned with existing and future experimental programs o Have taken an important role in developing Atlas participation o Will provide leadership in West Coast Atlas physics effort centered at SLAC  Active postdoc program attracting top candidates o Vibrant element of SLAC’s particle physics community Peskin

Strategic Overview for Elementary Particle Physics25 ILC Detector Jaros, Raubenheimer

Strategic Overview for Elementary Particle Physics26 LCD overall strategy  Factors driving development timeline o 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 2009 o 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 partners o 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

Strategic Overview for Elementary Particle Physics27 SLAC leading Silicon Detector Design Study oProviding Computing/Simulation infrastructure for all SiD oEngaging collaborators at Fermilab, BNL, Argonne, many US Universities. Developing international ties (KEK, Tokyo, Annecy, Oxford) oCoordinating & pursuing detector R&D  Si/W calorimetry and KPiX ASIC  Tracker design/Si microstrips  CMOS pixels for vertex detector oOptimizing & benchmarking SiD Design SiD detector outline document completed with 130 authors

Strategic Overview for Elementary Particle Physics28 Ongoing R&D goals for SiD at SLAC  Ecal o KPiX, new Si sensors, prototype, beam test, mechanical design, proof of principle  Main Tracker o Tracker Si sensor, prototype sensor modules, beam test  Vertex Tracker o Evaluate performance, mechanical design (with FNAL), develop sensor  Reconstruction Code o Perfect particle-flow algorithm, tracking pattern recognition  Benchmarking/Analysis/Design Optimization o Detector performance requirements, new physics analyses, global optimization, subsystem optimization

Strategic Overview for Elementary Particle Physics29 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 identified o 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 community o 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 Physics30 SiD timeline SiD Construction Data takingOngoing analysis R&D

Strategic Overview for Elementary Particle Physics31 EXO: Enriched Xenon Observatory Rowson

Strategic Overview for Elementary Particle Physics32 normal hierarchy inverted hierarchy 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 model 0 process only proceeds if ’s are their own antiparticles (Majorana) and massive  For 0  decay, the rate ~ 2. ~(1 – 4) meV normal hierarchy ~(15-60) meV inverted hierarchy

Strategic Overview for Elementary Particle Physics33 EXO experimental strategy  Detect Standard Model 2 double beta decays o Use (liquid) xenon as source and detector o Xe 136 is a relatively easy isotope to enrich – and – EXO has 200 Kg on campus!!  Developing background free next generation experiment o Rejecting 2 neutrino decay backgrounds: Energy resolution in TPC using ionization and scintillation light o Rejecting external backgrounds: Use radiologically quiet materials to build and shield apparatus Locate apparatus in radiologically quiet area = deep underground salt deposit at WIPP o Turn experiment into coincidence experiment by detecting nuclear daughter of double beta decay of Xe 136 to Ba 136 (one single ion at a time!) Unique feature of EXO Identify event-by-event

Strategic Overview for Elementary Particle Physics34 EXO-200 will use 200 kg of 80% enriched Xe 136; it will not employ barium ion tagging. The goals of the EXO-200 program are : oTest the LXe TPC operation : energy and spatial resolution, chemical purity issues, mechanical design and all backgrounds due to radioactivity and cosmic radiation. oObserve 2  decay in Xe 136 for the first time and measure the rate of this important 0  background. oConfirm or refute the controversial claim of Klapdor et al. (Observation of 0  in Ge 76 → 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 Physics35 Full EXO neutrino mass sensitivity

Strategic Overview for Elementary Particle Physics36 EXO timeline EXO-200 Construction Data takingOngoing analysis R&D Full EXO

Strategic Overview for Elementary Particle Physics37 Summary of EPP program elements SiD Atlas BABAR Full EXO EXO-200 Construction Data takingOngoing analysis R&D

Strategic Overview for Elementary Particle Physics38 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 priorities o 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