~900m AMSL. SuperKEKB 50 ab -1. 1ab -1. Henryk Palka IFJ PAN

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1 Status of SuperKEKB and Belle II SuperKEKB 50 ab -1 ~900m AMSL KEKB 1ab -1 <20m AMSL 1 IFJ PAN

2 Ski resorts 80 km Beautiful physics needs beautiful enviroments Sightseeing 80km Pacific ocean 50km Spa (Onsen) 120 km Tsukuba Restaurant 2km Tsukuba is nice place to study charm and beauty 2

3 Outline Why SuperKEKB / Belle II Belle and KEKB legacy SuperKEKB upgrade Belle II detector Background expectations Distributed computing for Belle II (Grids, Clouds) Belle II Collaboration Conclusions 3

4 Why we need SuperKEKB & Belle II Flavour physics is experimentaly driven field: e.g. the SM : only organisational principles and consistency relations Most of the KEKB/Belle CPV measurements (~1ab -1 ) are statisticaly limited improve them for further scrutiny of theory predictions e.g. some of the measurements suggest tensions w.r.t the SM values ( too low stat. significance to claim discovery) Clean, low multiplicity experiment, with complete final state reconstruction, many direct measurements with no ref. to MC good chance to see the unexpected 4

5 Belle Legacy Confirmed the SM Kobayashi-Maskawa mechanism of CP violation 5

6 Examples of measurements to look for NP 6

7 Examples of measurements to look for NP 7

8 Flavour Physics in the LHC Era DNA test of NP SuperKEKB measurements are complementary to direct searches for NP at the LHC 8

9 KEKB Legacy 9

10 KEKB performance World record luminosity: 2.1 x cm -2 s -1, twice the design value 1 ab -1 of integrated luminosity Still kicking till end o June

11 SuperKEKB goal: x40 luminosity increase 11

12 SuperKEKB: nano-beams collision scheme 12

13 SuperKEKB upgrade 13

14 S-KEKB Luminosity Projection 14

15 Belle II Detector Designed for improved performance and to cope with higher event rates and backgrounds KLM: RPC & Scint+SiPM ECL: CsI(Tl) & CsI PID: TOP & AF-RICH CDC: larger drift chamber SVD: 2 DEPFET pixels layers + 4 DSSD layers new DAQ: dead time free readout, high speed 15

16 PXD based on DEPFET Sensor Depleted P-channel FET gate DEPFET- matrix off on off reset reset off off n x m pixel off off V GATE, OFF V GATE, ON I DRAIN drain 0 suppression V CLEAR, ON V CLEAR, OFF V CLEAR-Control thin sensor, still large signal, fast signal collection low noise low power output ASICs on sensor: Switcher DCD (drain current digitizer) 16

17 PXD Layout, Control & DAQ 2 cm Pixels: 50 x 50(75) µm half ladder: 800 rows 250 cols 15 x 70 (85) mm ~20 cm Switcher DCD DHP Patch- Panel DHH 2-3 m DAQ, Opt. Trigger, Data Timimg TWP Power, Control Cu Opt. PS, Slow control Thickness: 75 µm total of 8 Mpx 17

18 PXD Mechanics, Outer Layer Integrated support and cooling (CO2) structure ladders are self-supporting ( >140 mm) (construction: K. Ackermann, MPI) Realistic mockup is constructed (PXD + SVD) to study cooling 18

19 Belle II SVD 4 layers R=4-12cm (lever arm, K s0 eff.) Slanted Fwd (cluster size, less m.scatt. material) DSSD Readout chips (APV25) thinned to 100µm, bonded on detectors (small capacitance good S/N) Rerouting with flex capton fan-out, wraped to opposite side Origami design (HEPHY Vienna) 19

20 Belle II SVD Origami module prototypes 20

21 Material budget of Si-Tracking System C. Kiesling, TDR Review Panel Meeting, KEK, May 23,

22 Vertex Detector Less Coulomb scatterings σ = a + b pβ sin ν θ σ[µm] Pixel detector close to the beam pipe σ[µm] 30µm 20µm Belle Belle II pβsin(θ) 3/2 [GeV/c] pβsin(θ) 5/2 [GeV/c] 22

23 Belle II Drift Chamber small cell, longer lever arm, wave-form sampling Better momentum resol. & de/dx measurements 23

24 PID: Time-of-Propagation Counter & Aerogel Focusing Rich Aerogel proximity focusing RICH TOP Different opening angles for particles with the same momenta diff. propagation lengths (=propagation time, ~100ps for π/k) 24

25 Backgrounds: S-KEKB nano-beams scheme New scheme, no measurements, predictions are uncertain Expectation: independent Q magnets shall reduce background drastically compared to the shared Q Scale factors wrt Belle, based on I, Lumi, lifetime: Q works also as bending magnet for the outgoing beam Background component Scale factor wrt Belle SR from upstream SR from final Q (backscatter) 2/1600 Beam gas 2-3 v.small (prelim.:5σ beams, nongaussian tails to be studied) Touschek Radiative Bhabha (charged) 40/1600 Scaled with beam lifetime Radiative Bhabha (neutral)

26 Background S-KEKB nano-beams (educated guess) Scaled according to the composition obtained a few years ago. (Well) below x20. Background composition will be updated. For a conservative estimate we keep assuming 20 times Belle background level 26

27 Computing resources 27

28 Belle II computing model Grids, Clouds, Local: Common framework for DAQ and offline based on root I/O Cloud = elastic resources mgt based on virtualisation 28

29 Virtualisation basics Old idea: IBM VM/370 in 80 s Linux Linux (devel) XP Win7 MacOS Virtual Machine Monitor Hardware 4coreIntel 100 core Tilera CPUs: 29

30 Belle II Distributed Computing Our own light-weight tool to submit jobs to Grid ( based on CreamCE ) Developed the framework to submit jobs to Grid(lcg), comercial Cloud (EC2) and local sites at the same time (based on DIRAC LHCb s WMS) Develope OpenSorce Cloud system for academic uses: the project started at IFJ PAN Krakow, ~1K cores 30

31 Belle II Collaboration June 2004: Letter of Intent March 2008: First proto collaboration meeting December 2008: Belle II founded ~300 members 47 institutes from 13 countries 31

32 Belle II Worldwide You are welcome to join! 32

33 Conclusions: The status of the project The project obtained preliminary approval by Japanese government in January Final (funding) decision expected soon Technical Design Report: has been completed (~480 pages), reviewed 2 weeks ago by external int. Comm., will be published in July Belle finishes data taking at end of June, thus permitting the KEKB upgrade work We are well on track to resume data taking in 2014 and looking forward to friendly competition with SuperB and LHCb Int. Rev. Comm.: Marcel Demarteau, Andrey Golutvin, Yuval Grossman, Yoshitaka Kuno, PereMato, Tatsuya Nakada, Niko Neufeld, Tomasz Skwarnicki, Mike Sullivan, and William Trischuk 33

34 Backup 34

35 Physics at Super B Factory 35

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42 Expected performance 42

43 Belle II Detector Designed for improved performance and to cope with higher event rates and backgrounds KLM CDC Top ECL A-RICH ECL CsI SVD PXD SVD: 2 DEPFET pixels layers + 4 DSSD layers CDC: small cell, long lever arm, wave-form sampl. TOP +Aerogel Focusing RICH ECL: waveform sampling, pure CsI for end-caps KLM: Scintillator +SiPM (end-caps) new dead time free readout and high speed DAQ systems 43

44 QED background simulation First PXD layer, spectrum normalized to one event These (additional) tracks yield an occupancy of 0.1 % PT th cut Lab Energy lower part PT th cut Lab Energy lower part Electron KoralW (Jadach, Skrzypek) Berends Daverfeldt Kleiss Entries 792 Mean RMS KoralW simulation constants confirmed by the KoralW authors Such spectra have never been measured yet: recently background study runs taken at different conditions in Belle GeV 44 44

45 Benefits of virtualisation Site perspective Resource flexibility (e.g. wrt Linux distributions) Easy resources management User perspective Isolation from environment: multisystem applications identical environment on multiple sites identical environment on local machine Drawbacks: - performance penalty (depends on virt. method) number crunching: negligible, I/O varies. 45