ORKA at Fermilab: Seeking New Physics with Measurements Seeking New - PowerPoint PPT Presentation

ORKA at Fermilab: Seeking New Physics with Measurements Seeking New Physics with Measurements         of the "Golden Kaon" Decay K of the Golden Kaon Decay K Douglas Bryman University of British Columbia April 25, 2013 Argonne Intensity Frontier Workshop

Precision Flavor Physics in the LHC Era A small set of crucial rare particle decays extremely sensitive to new physics at high mass scales p y g   High precsion measurments of the ultra-rare K Q( ) Q(L) Flavor Processes to Study NP y       1(2) -e Conversion, e , eee    ( ( K ) )  e          0 0 2 K , K L           3(3) ( ) b s , , B , , ... Discoveries of new physics at the LHC and elsewhere will require a range of p y q g precision flavor physics experiments to home in on the new interpretation. 2

     K in the Standard Model   The K decays are the most precisely predicted FCNC decays . CERN-ESG-005 μ (s γ d )( ν γ ν ) A single effective operator L L L μ L Dominated by top quark  (charm significant, but controlled) Hadronic matrix element shared with Ke3 Remain clean in most New Physics models      -11 B ( K ) = (7.8 ± 0.8) x 10 Expect total SM theory error ≤ 6%. SM    0 0 -11 B ( K ) = (2.43 ± 0.39) x 10 30% deviation from the SM SM L would be a 5  signal of NP J. Brod, M. Gorbahn, E. Stamou PRD83,034030(2011)

  K : High Sensitivity to New Physics High mass scale effects, Warped Extra Dimensions as a Theory of Flavor, Z’, …??         0 0 B( K ) vs. B( K ) L   Z ' ( m 5 30 TeV ) Z ' 11 →π 0 νν )x10 1 L → SM Br(K 0      11 Br K ( ) 10 x Buras, De Fazio, Girrbach D. M. Straub, arXiv:1012.3893 arXiv:1211.1896 4

Kamenik and Smith (2012) ( ) “FCNC portals to the dark sector”      Dark Sector Decays Dark Sector Decays K B K B / / XX XX compete compete   with SM Decays K B /  n 6 Operator 2 2 m g g   I V V Dimensional tI tI tJ tJ    n n 4 4 2 2 2 2 M M 16 16 Analysis W K decays Highly sensitive for low dimension for low dimension operators link.springer.com/content/pdf/10.1007/JHEP03(2012)090

Challenges for Measuring       K ( )      0 K 64%   21%    K      -11 B ( K ) = (7.8 ± 0.8) x 10 SM I Experimentally weak II signature: backgrounds exceed signals by >10 10 exceed signals by 10 • Determine everything possible about the K and p • ฀ p + /µ + particle ID better than 10 6 ( p + → µ + → e + ) • Work in the CM system (stopped K + ) • Eliminate events with extra charged particles or photons * ฀ p 0 inefficiency < 10 -6 • • Suppress backgrounds well below the expected signal (S/N~10) • * Predict backgrounds from data : dual independent cuts • * Use “Blind analysis” techniques • * Test predictions with outside-the-signal-region measurements 6 • Evaluate candidate events with S/N function

BNL E949 – 3 nd generation  Stop 700 MeV/c K Scintillating fiber tgt. RS RS   Momentum in DC Energy, range in RS     e DC   6 10 suppression  4 Photon Veto PV  6 0 >10 suppression pp 4  Photon Veto Photon Veto          e        e  Decay Sequence Decay Sequence     Veto Additional Veto Additional     Charged Tracks Charged Tracks e  e  e         e  e  500 MHz digitizers 7

Background Suppression: E949 Extreme Photon Detection Efficiency Rejection vs. Acceptance j p 6 6 7 7 0 R j   0 Rejection: >10 i 10 10 10 Possibly the most efficient •E949 photon detector built so far. •E787 VPI&SU 8

       0 11 Background Suppression: 21% <10 K cuts:  Dual Veto and Kinematics (P,R,E...)   Veto Reversed Veto Applied Range vs. Energy Mome ntu m  Max. veto Check for correlations

Pion Range vs. Energy 10 10 (0.78 +- 0.08) 10

      0 0 K Experiments History pe e ts sto y L L  8  2.6 10 x 11 J. Ma 2011

  Emerging K Measurements      K at CERN 75 GeV Kaon Decays-in-flight Proton beam from SPS • Builds on NA-31/NA-48 • Un-separated GHz beam • Aim: 40-50 events/yr at SM • Under construction; start 2013 12

    0 8 5 Rejection goal: 10 Rejection goal: 10 Rejection goal: 10 Rejection goal: 10   / RICH separation up to 35 GeV/c 13 2 Beam tracking: 40 MHz/cm

   0 0 K at J-PARC L  8  Impoved setup based on KEK E391a ( 2.6 10 x ) • Improved J-PARC Beam line • Upgraded Detector • 100 x proton intensity • Aim: few events (S/B~1) at SM ( ) • Under construction; start 2013 14 J. Ma 2011

 CsI Calorimeter: t (50 MeV)~500 ps Expected Photon Veto Performance    0 0 0 Principal background: K L J. Ma 2011, T. Yamanaka 2012

ORKA at Fermilab ORKA at Fermilab  17 institutes in six countries: Canada, China, Italy, Mexico, Russia, USA  Six US universities  Two US National Laboratories  Leadership from previous BNL and FNAL US rare kaon decay experiments

ORKA at the FNALMain Injector         th 4 4 Generation Generation K K Experiment Experiment Incremental Improvements p • 600 MeV/c • K stopping rate x5 with comparable bl instantaneous rate • Larger solid angle • Acceptance x 10 p • Fine segmentation, improved resolutions 30% deviation from the SM Reduced backgrounds: <5% precision g p would be a 5  signal of NP Overall, > 100 x sensitivity

ORKA at Fermilab Main Injector Slow Spill 75 KW 95 GeV/c 44% duty factor (10 s cycle, 4.4 s spill) CDF(B0) collision hall: Existing tunnels and hall, Rad hard, adequate space, existing superconducting magnet superconducting magnet, A0->B0 beamline needed; (required interplay with IARC) 18

•The ORKA new detector payload replaces the CDF tracker volume. E949 Central tracker (similar diameter to ORKA) 19

Kaon Beamline Design 600 MeV/c separated K beam ( K/ π ~4 ) Measure kaon decays at rest. 95 GeV Protons  7 10 K / s 44% . . D F •T. Kobilarcik, D. Jensen (FNAL), et al. G4Beamline studies

Evolution to 4 th Generation Detector • Simulations studies • R & D underway on detector refinements y • ILCroot framework established • Efficient photon detectors • Range stack segmentation and readout - Adriano (INFN), Shashlyik • Photon veto geometry and function • Solid state photo-sensors -- SiPMs • Target segmentation and readout g g • Range stack tracking -- GEM • Drift chamber parameters • Low mass drift chamber design • Kaon beam line: G4Beamline • Preliminary engineering concepts • Detector support in CDF magnet • Installation issues • Power, cooling and cabling issues

ILCroot Simulations ILCroot Simulations BNL/FNAL/INFN/TRIUMF-UBC

ORKA Detector improvements Incremental increases in signal acceptance based largely on E787/E949 measurements. Additional acceptance gains expected from trigger improvements. 24

      e        e  Decay Sequence Decay Sequence           e  e  25

      e        e  Decay Sequence Decay Sequence ORKA ORKA             e  e  26

ORKA ORKA ORKA K   K   K  Decay Time K  Decay Time     ORKA 2 ns 2 ns 2 ns 2 ns 1 ns 1 ns 27

  Kinematics   Kinematics             ORKA ORKA ORKA 28

Scintillating Fiber Target E949 3.1 m long, single ended readout ORKA 1 m long, double ended readout, SiPMs Acceptance Increase: 1.06±0.06   Beam Beam K  MPPC MPPC Instrumentation Instrumentation Instrumentation Instrumentation Target Fibers K  K  Target Target 29

Photon Veto Improvements E949 1 7.3 Radiation Lengths ORKA ORKA 23 0 R di ti 23.0 Radiation Lengths L th Acceptance Increase : 1.65  0.39  0.18 Estimate based on simulated KOPIO PV performance Adjusted to agree with E949 PV efficiency. Shashlyk – Calorimeter Candidate for ORKA 30

Shashlyk Beam Measurements Simulation : Combined Energy Resolution 2.7%     E GeV ( )