Flavour Physics in KCETA

KIT – University of the State of Baden-Wuerttemberg and National Research Center of the Helmholtz Association

IEKP KCETA Karlsruhe Institute of Technology KIT

www.kit.edu

Flavour Physics in KCETA

KCETA-Beiratssitzung, 21.Mai 2010Prof. Dr. Michael Feindt

IEKP, KCETA,KIT 2

Institut für Experimentelle Kernphysik:Prof. Dr. M. Feindt, Dr. Th. Kuhr, Dr. M. Kreps, Dr. A. Zupanc et al: •CDF II at Tevatron Collider(USA): Flavour physics analyses•Belle at KEKB B factory (Japan): Software development Flavour physics analyses•Belle II at future super-B factory (Japan): Software concepts and reconstruction algorithms•Industry collaboration with Phi-T GmbH on NeuroBayes neural computing

Prof. Dr .Th. Müller, Dr. H.-J. Simonis et al.:Belle II at future KEKB super-B factory (Japan) : Pixel detector hardware Institut für Theoretische Teilchenphysik:Prof. Dr. U. Nierste et al.: Theoretical studies on flavour physics, signatures for new physics

Close collaboration between experiment and theory (e.g. weekly b lunch)

Karlsruhe engagement in flavour physics

Flavour Physics at KCETA 2010 - Michael Feindt

IEKP, KCETA,KIT 3

Theoretical work on flavour physics (U. Nierste et al.):

• Generic Minimal Supersymmetric Standard Model (MSSM):– calculation of chirally enhanced corrections to FCNC processes,– supersymmetric renormalisation of the CKM matrix,– new constraints derived from charged-current processes,– implications from the “B → Kπ puzzle” for Bs → φρ0 and Bs → φπ0,– constraining sparticle masses from B−B mixing.

• Grand unified theories (GUT):

-Effects from dimension-5 Yukawa operators on µ → eγ and εK in SU(5) and SO(10) GUT models.


IEKP, KCETA,KIT 4

Theoretical work on flavour physics (U. Nierste et al.):

• MSSM with minimal flavour violation (MFV):– analytic resummation of tanβ-enhanced corrections to all orders in

perturbation theory and all orders of MW2 /MSUSY

2,– novel large effect in the mixing-induced CP asymmetry in Bs →ΦKS

– study of MSSM Higgs sector corrections in B−B mixing, – MFV as an alternative to R-parity to suppress proton decay, – calculation of tan β-enhanced two-loop correction to (g − 2)µ.


IEKP, KCETA,KIT 5

CDF II b-physics (Convenor: Dr. Michal Kreps, KIT)

Getting calmer slowly, but still very productive. (We now understand the CDF experiment very well). Important recent KIT contributions to:

• Discovery of Bs particle antiparticle oscillations (update underway) • Measurement of lifetime difference of Bs mass eigenstates

and a possible CP violating phase in BsJ/y Φ (Theory: Nierste et al.)•First observation of Bs1

•Most precise measurements of Bs2*•Most precise mass & width of B1 and B2*•Spin-parity and most precise mass measurement of X(3872)•Development of new NeuroBayes flavour tagger (improving εD2 by ≈50%)•Search for Xb, measurement of ϒ(1S,2S,3S) -Polarisation•Most precise measurements of excited charm baryons Λc*, Σc and Σc*•Most precise measurement of BS DS

(*)DS(*) branching ratios

•First observation of BSJ/ψ f0(985)•No b/c flavour physics, but also important contributions (NeuroBayes) to •Discovery of single top quark production (KCETA)•First exclusion limit on a high mass Standard Model Higgs


IEKP, KCETA,KIT 6

Alternative Flavour Physics


B0,B+ pairs, nothing elseVery cleanHuge luminosity

B0,B+, BS, Λ bCrowded eventsHigh energy Huge cross section, large rate if triggered

IEKP, KCETA,KIT 7

B-factory experiment at KEKB accelerator in Japan Competitor of BaBar exp.

KEKB accelerator holds world record in instantaneous (=2.1x10-34 s-1 cm-2) and integrated luminosity (1000 fb-1)

Belle has about 1 billion (109) B-meson pairs on tape

Belle


IEKP, KCETA,KIT 8

Physics

Precision measurements of fundamental SM parameters (CKM matrix)

in total: 317 physics publications

Search for physics beyond the SM

B0 tag_B0 tag

Discovery of new particles


IEKP, KCETA,KIT 9

(1/2) Nobel price 2008

Makoto Kobayashi Toshihide Maskawa

"for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature"

Final experimental proof:

CP-violation in B systemby experiments BaBar and Belle


IEKP, KCETA,KIT 10

Perfect agreement of flavour physics precision measurements with SM already rules out large part of (minimal) SUSY parameter space.

Due to interference effects large sensitivity to new physics e.g. in loops. Complementary to high energy LHC program and partly to LHCb. If new physics exists, it must show up in B decays!

Physics Case for Belle II

0.001

0.01

0.1

1 10 [TeV]Energy

Cou

plin

g co

nsta

nt LH

C

Teva

tron

100

SuperKEKB

KEKB


IEKP, KCETA,KIT 11 Flavour Physics at KCETA 2010 - Michael Feindt

IEKP, KCETA,KIT 12

KCETA- contributionsto Belle:

Introduction of NeuroBayes neural computing into Belle.

Rewrite of parts of the reconstruction and analysis codes withnovel probabilistic algorithms very successful.

Also as prototype for Belle II software. NeuroBayes enhances efficiency of flavour tagging

calibration reaction B-> D* l ν by 71% at same purity


IEKP, KCETA,KIT 13

Belle: Full reconstruction of B mesons in >1000 decay chains.Hierarchical system with >100 NeuroBayes networks, fully automatic.Preliminary gain about factor 2 compared to classical algorithm at same purity(corresponds to a few years of additional data taking for many interesting analyses)


IEKP, KCETA,KIT 14

Belle II

Super-B-factory searching for new physics e.g. by precison studies of CP-violation and rare decays (forbidden in SM) in B-meson systemKEKB is luminosity world record holder: 2.11*10-34 cm-2 s-1

Upgrade in progress to reach 50 times higher luminosityJapanese government approved project in Jan 2010 Belle II TDR underwayKIT is one of founding members of the Belle II CollaborationLarge contributions and important responsibilities in hardware (DEPFET pixel detetor) and software


IEKP, KCETA,KIT 15

Belle II pixel detector

detector construction:

module layout (130x15 mm):

overview of Belle II vertex detector

Pixel detector

PXD layout(20 modules in 2 layers)

beam pipe

(DEPFET, 75 µm thick)

power consumption:18 W x 20 = 360 W!

hard requirement:TDEPFET < 35°C

Responsible for PXD Cooling: Dr. Hans-Jürgen Simonis (KIT)


IEKP, KCETA,KIT 16

DEPFET Module Dummy

dummy module: silicon with heater foils as power loadmeasure temperature distribution across module

thermal simulation offull module (COMSOL)

dummy module

peltier elementpre-cooling

support surface

conclusion:good agreement between measurement andsimulationactive area

(DEPFET)support surface

power load: 18 W


IEKP, KCETA,KIT 17

Pixel detector end flangecopper mockup of PXD end flange from our workshopmeasure temperature loss between surface and coolant

180 W

max. temperature loss for expected power load (180 W): 23°Cconclusion: need for CO2 cooling to reach required temperature on surface

“outside”“nose”

“inside”

liquid inlet/outlet

cooling channel

positions of Pt1000


IEKP, KCETA,KIT 18

Pixel detector design optimization studiescomparison of PXD performance (z-resolution) for different sensor thicknesses (baseline 50 µm)benchmark analysis with simulated physics channel

optimum thickness: 75 - 100 µmconclusion: new baseline 75 µm

(with 100 µm as option, more studies needed)

B D*D*


IEKP, KCETA,KIT 19

Software preparations for Belle II

Responsible for Belle II computing: Dr. Thomas Kuhr (KIT)Responsible for Belle II track reconstruction SW: Dr. Martin Heck (KIT)

Sketch of the Belle II computing model


IEKP, KCETA,KIT 20

Technology Transfer - Industry Collaboration


• IEKP had/has very successful applications of NeuroBayes®- algorithm in DELPHI, CDF II, CMS and Belle.• International Data-Mining Cup 2005–2009: KIT always top rankings using NeuroBayes®

2002: Spin-off company Phi-T GmbH founded: NeuroBayes® statistical future prognoses andrisk preditions for financial institutions, insurances, trading, medicine and industry. Mostly not taken too seriously then.

In the meantime 35 employees (mainly Ph.D. from HEP).Steady further development of NeuroBayes®, very successful large projects, prominent clients,good press echo, second office in Hamburg. Phi-T manages fully automatically a 130 mio € investment fund and steers supply chain of world’s largest mail order business (OTTO).

2010: Phi-T supplies CERN with free NeuroBayes® licences.Successful first applications in ATLAS and LHCb just reported.

IEKP, KCETA,KIT 21

Funding of Belle engagement Applied for DFG-Kosselek project for developing neural computing for Belle II (was unfortunately rejected)

Applied for BMBF project to fund German DEPFET pixel detector for Belle II (accepted, but on a low level)

Problem of BMBF / DFG exclusive funding.

Presently Belle is a very low budget project (institute + KCETA) although we already have very large impact, visibility, conference talks and publications with Belle and Belle II.

Advice/help welcome Flavour Physics at KCETA 2010 - Michael Feindt

Documents

Flavour Physics in KCETA