2024 Belle II Physics Week

14 Oct 2024, 08:30 → 18 Oct 2024, 19:00 Asia/Tokyo

Kobayashi Hall (KEK)

James Frederick Libby (BELLE (BELLE II Experiment)), Karim Trabelsi (TYL - KEK), Kenji Inami (Nagoya), Laura Zani (INFN of Roma Tre), Torben Ferber (Karlsruhe Institute of Technology (KIT))

The 2024 Belle II Physics Week will be in-person gathering intended to foster open discussion among Belle II experimentalists and theory experts.

 

All collaborators are invited to join KEK for in-person attendance. 

 

The week will consist of two parts: 

 

- Mornings: a school for PhD students and early postdocs with general pedagogical lectures about aspects of Belle II and flavour physics. It will include plenary sessions on phenomenology, detectors, and benchmark analyses along with in-person hands-on work. Plenary lectures will be recorded. In-person hands-on will be conducted on-site. Online participation will be also possible.

 

 - Afternoons: a workshop, this is the second in a series of workshops focusing on special topics at the interface of theory and experiment that are priorities for the Belle II program. 

 

This year the workshop is on tau and dark sector at Belle II. 

 

We’d like to openly take on challenges, issues and opportunities at Belle II to generate a program of prioritised measurements/studies to advance the knowledge of these fundamental sectors in the next 3 years. 

 

A generous amount of discussion time is allotted to each talk in the program, which also includes extensive break out sessions. In this spirit, participation to the workshop is intended to be only in person to maximize the interactions and discussion. The workshop's discussions and conclusions will be documented in a short KEK report. 

 

Note that Wednesday evening we will have a poster session where Belle II students can present their work (analysis or else).

 

 Previous edition of physics week in 2023 was on Vcb determination.

 

Confirmed speakers include: Marco Ardu, Anke Biekoetter, Adrian Casais Vidal, Lorenzo Calibbi, Pablo Roig Garcés, Stefania Gori, Martin Hoferichter, Nazila Mahmoudi, Giordon Stark, Olcyr Sumensari, Jure Zupan, Gilly Elor, Tobioka Kohsaku, Robert McGehee, Tomasz Procter, Lorenz Gaertner

 

Organization committee: T.Ferber, L.Zani, K.Inami, E.Passemar, M.Endo, G.Z.Krnkaic, S. Hashimoto, J.Libby, K. Trabelsi.

 

 - The registration fee will be 8,000 JPY covering coffee breaks and a social dinner on Tuesday. For those who does not join the social dinner, a reduced registration fee of 2,500 JPY will be applied. An invoice from PayPal will be sent to registrants' email address, according to the information given at the registration.

 

- There will be a social dinner on Tuesday, October 15th. Participation is warmly recommended.

 

Further details about logistics can be found in 'Transportation' and 'Accommodation' sections on the left menu. 
 

Monday, 14 October

School

1 Theory introduction to the dark sector

Speaker: Prof. Stefania Gori (UCSC)

2 tau analyses 101

Speaker: Soeren Prell (Iowa State University)

11:00 Coffee

3 Event generators for low multiplicity and tau

Speaker: Swagato Banerjee (University of Louisville (U.S.))

Workshop on taus and dark sectors

Conveners: Emilie Passemar (Indiana), Laura Zani (INFN of Roma Tre), Torben Ferber (Karlsruhe Institute of Technology (KIT))

4 Opportunities for testing the Standard Model with Tau leptonic decays at Belle II

Speaker: Pablo Roig

Speaker: Pablo Roig Garcés ((CINVESTAV))

5 LFV in tau decays and possibility for new mediators: complementarity of tau and muon

Speaker: Lorenzo Calibbi

Speaker: Lorenzo Calibbi ((Nankai U.))

6 Mesogenesis: Signals of Baryogenesis at B-Factories

Mesogenesis is a testable mechanism for generating both the matter-antimatter (baryon) asymmetry and the dark matter of the Universe. Mesogenesis leverages the CP violation within charged or neutral Standard Model meson systems; in one version of the mechanism the entire baryon asymmetry can be generated with only the Standard Model contributions to the CP violation. After giving an overview of the existing variations of Mesogenesis (and their respective signals), I will summarize specific searches that can be conducted by Belle to discover Mesogenesis. The Belle collaboration has already set a limit on the branching fraction for a neutral B meson decaying into Lambda baryon and missing energy, which constrains one channel through which Neutral B-Mesogenesis can proceed. I will discuss the implications of this search for the entire parameter space of Mesogenesis mechanisms, and further motivate other Mesogenesis searches that Belle is uniquely equipped for. While B-factories truly are the ideal environment to discover Mesogenesis, a variety of indirect signals exist at hadron colliders, neutrino experiments, and through astrophysical observations. I will conclude by presenting an overview of the various complementary experimental searches that can be conducted. Such an experimental program has the potential to fully prope the model space of this mechanism.

Speaker: Gilly Elor (U. Texas)

15:25 Coffee break

7 dark sector (tbc)

Speaker: Tobioka Kohsaku (U. Florida)

8 Prospects on the magnetic(electric) moment of the tau and polarized beams

Speaker: Martin Hofenrichter

Speaker: Martin Hoferichter ((Bern U.))

Tuesday, 15 October

School

9 Theory introduction to the dark sector

Speaker: Prof. Stefania Gori (UCSC)

10 Introduction to the trigger

Speaker: Taichiro Koga (BELLE (BELLE II Experiment))

11:00 Coffee

11 tau and the standard model

Speaker: Prof. Emilie Passemar (Indiana)

Workshop on taus and dark sectors

Conveners: Emilie Passemar (Indiana), Laura Zani (INFN of Roma Tre), Torben Ferber (Karlsruhe Institute of Technology (KIT))

12 Testing SM through precise measurements of hadronic tau decays at Belle II

Speaker: TBA

Speaker: Pablo Roig Garcés ((CINVESTAV))

13 Lattice QCD results and tau measurements exchange: important inputs for precision tests

TBA

Speaker: Mattia Bruno (Bicocca University Milan)

14 Dark sector searches with leptons

Speaker: Stefania Gori (UCSC)

15:30 Coffee break

15 Statistical analysis, interpretation and recasting results (tbc)

TBD

Speaker: Mahmoudi Nazila (U. Lyon)

16 Statistical analysis, interpretation and recasting results (II) (tbc)

TBD

Speaker: Tomasz Procter (U. Glasgow)

Wednesday, 16 October

School

17 Connection between flavour and the dark sector

Speaker: Dr Olcyr Sumensari (IJCLab)

18 Dark sector analysis basics

Speaker: Luigi Corona (BELLE (BELLE II Experiment))

11:00 Coffee

19 Limit setting: a how to

Speaker: Enrico Graziani (INFN - Roma 3)

Workshop on taus and dark sectors

Conveners: Emilie Passemar (Indiana), Laura Zani (INFN of Roma Tre), Torben Ferber (Karlsruhe Institute of Technology (KIT))

20 State of the art statistics: pyhf

Speaker: Giordon Stark

21 Challenging BSM search with taus

Speaker: Jure Zupan

Speaker: Jure Zupan (Cincinnati)

22 Dark Matter, Baryogenesis, & Naturalness at Belle II

Belle II is sensitive to O(GeV) visibly-decaying dark photons which kinetically mix with the Standard Model photon (ie through the vector portal). Interestingly, there are a number of motivated, non-vanilla BSM models which all point to the masses and couplings that are imminently detectable there. We’ll cover a range of such scenarios with broad theoretical motivations such as self-interacting dark matter, asymmetric dark matter & baryogengesis, and models of neutral naturalness.

Speaker: Robert McGehee (U. Minnesota)

15:30 Coffee break

23 Lepton Flavour Violation at Belle II

Speaker: Marco Ardu

Speaker: Marco Ardu (( Valencia U., IFIC))

24 Efficient reinterpretation with model agnostic likelihoods

Speaker: Lorenz Ennio Gaertner (BELLE (BELLE II Experiment))

25 Global view on DS searches

Effective field theory (EFT) provides a model-agnostic way to describe new physics and, in particular, dark sectors. In this talk, we will discuss how and where Belle II contributes crucial constraints on effective theories with light new (pseudo-) scalars. When analyzing the effects of these new physics theories, it is important to take into account all their possible interactions. We will discuss how global analyses of the couplings of new particles provide useful insights into the allowed parameter space and pinpoint yet untested regions.

Speaker: Anke Biekoetter (U. Mainz)

Poster session (sake and otsumami)

Thursday, 17 October

School

26 Basics of lepton flavour violation

Speaker: Prof. Jure Zupan (Cincinnati)

27 CDC: the heart of Belle II

Speaker: Nanae Taniguchi (BELLE (BELLE II Experiment))

11:00 Coffee

28 Dark sector at LHCb

Speaker: Dr Adrian Casais Vidal (MIT)

Workshop on taus and dark sectors

Conveners: Emilie Passemar (Indiana), Laura Zani (INFN of Roma Tre), Torben Ferber (Karlsruhe Institute of Technology (KIT))

29 Testing SM through precise measurements - summary

Speaker: Emilie Passemar (Indiana)

30 non-vanilla dark sector- summary

31 Discussion

speaker TBD

15:20 Coffee break

32 Beyond SM searches with taus -summary

Speaker: Olcyr Sumensari (IJCLab)

33 Statistical analysis, interpretation and recasting - summary

34 Discussion

speaker TBD

Friday, 18 October

School

35 Searching for the dark sector in B decay

Speaker: Slavomira Stefkova (KIT)

36 Particle ID overview

Speaker: Stefan Wallner (Max Planck Institute for Physics)