FJPPLFlavourPhysics < FJPPL

FJPPL Web>FJPPLprojects>FJPPLFlavourPhysics (2020-09-18, IsabelleRippBaudot) (raw view)EditAttach

<center>FLAV_03: *Flavour physics and theoretical challenge for precision* </center>

_Summary_:<br>
Flavour physics, and B physics in particular, constitutes one of the most promising probes of physics beyond the SM. The CP asymmetry measurements in the Bd and Bs systems as well as the observation of the large number of rare decays, such as B &#8594; Xs &#947; and Bs &#8594; µ+ µ &#8722;, have been studied at B factories as well as at LHCb. These processes are all induced by the loop level diagrams and thus, provide valuable indirect information on physics beyond the SM. Despite of a large expectation, there is no significant deviation from the SM observed so far. The very successful 7-8 !TeV runs of LHC have excluded a large parameter space for many of the new physics models. In this circumstance, the most urgent task is now to re-examine the viability of these models and to determine the new benchmark models and their search strategies for the forthcoming experiments. This project combines two joint efforts towards this goal: i) LHCb-Belle II-theory common discussion towards a global fit of the new physics parameters, ii) contributions to the theory-experiment working group towards Belle II start-up.

_French members_:<br>
*E. Kou*, F. Le Diberder, T. Moskalets, B. Moussallam, M-H. Schune

_Japanese members_: <br>
*T. Kaneko*, K. Hara, S. Hashimoto, K. Hayasaka, A. Ishikawa, S. Mishima, K. Trabelsi,

_References_:<br>
[1] Implications of LHCb measurements and future prospects
Published in Eur.Phys.J. C73 (2013) 2373
e-Print: arXiv:1208.3355 <br>
[2] !SuperKEKB TDR - Physics Motivation Chapter (2014)
https://belle2.cc.kek.jp/~twiki/pub/Public/B2TIP/SuperKEKBReport.pdf <br>
[3] Webpage of Belle II Theory Interface Platform (!B2TiP), an initiative to coordinate a joint theory-experiment effort to study the potential impacts of the Belle II program.
https://belle2.cc.kek.jp/~twiki/bin/view/Public/B2TIP

<center>------------------------------ </center>

<center>FLAV_05: *B flavour and Time Dependent CP violating measurement with Belle II* </center>

_Summary_:<br>
Time dependent asymmetry measurements (TDCPV) play a major role in flavor physics. They give access to CP violating parameters, which are central elements to test the Standard Model through the CKM matrix and which exhibit high sensitivity to New Physics. Our project ultimately intends to exploit the high sensitivity of TDCPV measurements to reveal indirectly New Physics in rare transitions b&#8594;s&#947; and b&#8594;sqq (q=s,d), which proceed through penguin diagrams. Conducting such advanced analysis at a B-factory requires two key ingredients: tagging the flavour of one of the B meson while the other decays into a flavour eigenstate and estimating with high precision the time difference (&#8710;t) between the two B decay vertices.
The Belle II experiment intends to stand at the forefront of flavour physics in the coming years by accumulating an integrated luminosity of 50 ab&#8203;-1 at the !SuperKEKB e+e- collider. However, in the first years of Belle II operation, the integrated luminosity growth follows the pace of the collider progresses toward high instantaneous luminosity and our understanding of the detector performances improves as well with time. The present project gathers physicists from Japan and France in order to reach robust time dependent asymmetry measurements with Belle II data in a timely manner. Members of this project have a strong leading role in Belle and Belle II collaborations regarding these measurements.
Our activities have started since 2019 with relatively simple measurements like B meson lifetime measurement and rediscovery of the main B decay into CP-eigenstate (J/Psi+Ks). The project continues with refining analysis tools (flavour tag, time resolution model) and with the reconstruction of rare final states (Ks Ks Ks as well as Ks pi+ pi- gamma).



_French members_:<br>
*J. Baudot*, G. Dujany, I. Ripp-Baudot, T. Fillinger, R. Rasheed

_Japanese members_: <br>
*K. Miyabayashi*, A. Gaz, Y. Yusa, Y. Ushiroda, H. Tanigawa

_References_:<br>
[1] R. Rasheed et al., "Measurement of the B0 lifetime using fully reconstructed hadronic decays in the 2019 Belle II dataset", BELLE2-CONF-PH-2020-003, arXiv:2005.07507.

Topic revision: r11 - 2020-09-18 - 08:59:28 - IsabelleRippBaudot

FJPPL

Webs
- ACAT
- ACGRID
- ACPP
- ASEPS
- Americas
- EMC2
- FAPPL
- FAPPS
- FCPPL
- FJPPL
- FKPPL
- FVPPL
- Feyn
- Main
- Sandbox
- TWiki

Copyright &© by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback