2023 Belle II Physics Week

30 Oct 2023, 08:30 → 3 Nov 2023, 19:00 Asia/Tokyo

Kobayashi Hall (KEK)

James Frederick Libby (BELLE (BELLE II Experiment)), Mirco Dorigo (INFN Trieste)

The 2023 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 first 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 precision |Vcb| measurements 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 this fundamental parameter 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. 

 

Organization committee: L. Cao, M. Dorigo, S. Hashimoto, T. Iijima, T. Kaneko, J. Libby, R. Mandal, D. Robinson, D. Tonelli, K. Trabelsi.

 

Confirmed speakers include: Luiz Vale Silva, Bob Kowalewski, Zoltan Ligeti, Markus Prim, Alejandro Vaquero, Florian Bernlochner, Jim Libby, Daniel Dorner, Kenta Uno, Matteo Fael, Judd Harrison, Marco Fedele, Marzia Bordone, Lu Cao, Lopamudra Mukherjee, Phill Urquijo, Keri Vos, Michele Papucci, Paolo Gambino. 

 

 - 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 31st. Participation is warmly recommended.

 

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

Monday, 30 October

08:30 → 12:45 School

SpeakApp

08:30 Flavour physics - 1

Speaker: Dr Rusa Mandal (IIT Gandhinagar)

Flavor-I_KEK.pdf

09:45 The anatomy of a semileptonic analysis

Speaker: Florian Bernlochner (Belle (SuperKEKB Experiment))

Anatomy_of_semileptonic_decays.pdf

RevModPhys.67.893.pdf

RevModPhys.88.035008.pdf

RevModPhys.94.015003.pdf

sl_amplitude.pdf

11:00 Coffee break

11:30 Performance: what we do and what you can do for us?

Speaker: Alessandro Gaz (University of Padova & INFN)

PhysWeek_performance_tasks.pdf

13:45 → 14:20 Workshop: Introduction

13:45 Opening remarks

Speaker: Mirco Dorigo (INFN Trieste)

Vcb-workshop-welcome.pdf

13:55 The role of |Vcb|

The role of Vcb in the global picture: impact of the Vcb puzzle on UT and NP searches

Speaker: Luiz Vale Silva (IFIC)

topics_VALE_SILVA.pdf

VALE_SILVA_Vcb_DF2.pdf

14:20 → 16:15 Workshop: Vcb exclusive

Convener: Dean Robinson (BNL)

14:20 Experimental challenges in exclusive measurements

Review recent measurements with focus on current limitations: are we already systematically limited? how to circumvent this?
 Is there a Vcb dependence on parametrisation (recent measurements do not indicate so)? Dependence on truncation on BGL expansion, how to choose (eg. nested hypothesis tests)? New ideas, eg down-feed D* in D categories to measure the w spectrum

Speaker: Robert Kowalewski (University of Victoria)

ExpChallengesInExclDecays.pdf

ExpChallengesInExclDecays - topics.pdf

15:20 Theoretical challenges in the exclusive determinations

Developments in FF model independent approaches. How to assess potential biases from various models or sum rule-based approaches? 
How do we systematically decide on the truncation order of a parametrization (Akaike IC, Nested Hyp. test, …). Can we develop a benchmark test to compare different methods? 
For HQET-based parametrizations of B -> D/D*, how do we assess the role of and incorporate second-order power corrections?

Speaker: Zoltan Ligeti (Berkley)

kek23.pdf

16:15 → 16:45 Coffee break

16:45 → 18:45 Workshop: Vcb exclusive

Convener: Takashi Kaneko (KEK)

16:45 Beyond unfolded distributions

Which measurements can we provide to improve knowledge on form factors? What are the shortcomings of unfolded distributions? 
What can we provide beyond/along-with them? 
What can angular analyses add?

Speaker: Markus Prim (BELLE (BELLE II Experiment))

B2PhysicsWeek.pdf

17:45 Lattice tensions

What are the tension: review/comparison of recent calculations by Fermilab/MILC,HPQCD,JLQCD. 
What are the key differences among the 3 calculations and possible origin of the tension? 
What's needed to identify the origin of the tension: what short-term future results/calculations are planned?

Speaker: Alejandro Vaquero (UNIZAR)

KEK-Talk.pdf

Slides.pdf

Tuesday, 31 October

08:30 → 12:45 School

SpeakApp

08:30 Flavour physics 2

Speaker: Rusa Mandal (IITGN)

Flavor-II_KEK.pdf

09:45 ECL: an overview

Speaker: Prof. Christopher Hearty (University of British Columbia / IPP)

ECL overview 1-Nov-2023.pdf

11:00 Coffee

11:30 Tracking: basics

Speaker: Yubo Han (BELLE (BELLE Gruppe))

Tracking_1031.pdf

13:30 → 18:00 How to use our SW and DP tools

Hands on session

Conveners: Frank Meier (Duke University), Giacomo De Pietro (Karlsruhe Institute of Technology), Dr Stefano Lacaprara (INFN Padova), Umberto Tamponi (INFN - Torino)

DP_physweek_Octo2023.pdf

13:45 → 14:15 Workshop: Vcb exclusive

Convener: Lu Cao (BELLE (BELLE Gruppe))

13:45 FF, polarisation and asymmetries in D*lnu

Discuss https://arxiv.org/abs/2305.15457 and DM

Speaker: Marco Fedele (KIT)

Fedele.pdf

14:15 → 16:15 Workshop: SL gap and inputs from other sectors

Convener: Lu Cao (BELLE (BELLE Gruppe))

14:15 SL gap: knowns and unknowns

What is the current knowledge of D(*)(n)pi l nu decays?
 What do we do to fill the gap? Are our assumptions and uncertainties 
(not only for Vcb) reliable? 
Can we do better and what recent measurements brought?

Speaker: Florian Bernlochner (Belle (SuperKEKB Experiment))

Known_and_Unknowns_inDstarstar_Decays.pdf

15:10 Can B hadronic help?

Can hadronic B decays (eg. B->D*eta pi) supplement info on SL-gap modes? Under which assumptions/limitations? Would like to stimulate a discussion on what measurements are possible and pressing on Bhad

Speaker: Mirco Dorigo (INFN Trieste)

Bhad_Vcbwokshop.pdf

15:45 Inputs from Charm

This talk will explore the successful endeavors of the BES-III experiment in simulating the decay processes of charmed mesons. Advanced decay models for multibody charm decays based on dedicated partial wave amplitude measurements will be introduced.

Speaker: Xinyu Shan (USTC)

D_Model_Shanxy_BESIII.pdf

16:15 → 16:45 Coffee break

16:45 → 18:30 Workshop: experimental challenges

Convener: Mirco Dorigo (INFN Trieste)

16:45 Ways to improve f+-/f00

To overcome the current used value affected by large isospin-breaking uncertainty, and to account for any c.m.-energy dependence

Speaker: James Frederick Libby (BELLE (BELLE II Experiment))

Physics week - f+-f00-v3.pdf

17:15 Slow-pion efficiency

The slow-pion efficiency and its associated systematic uncertainty is currently the major limitation of the exclusive measurement with B->D*(D0 pi_s) l nu decays. Can we improve the slow-pion efficiency? Can we reduce its systematic uncertainty?

Speaker: Daniel Dorner (BELLE (BELLE II Experiment))

Slow_Pions_PhysicsWeek_v4.pdf

17:45 Lepton ID challenges

A key ingredient of SL measurements are LID efficiencies, their corrections and systematic uncertainties. The talk review on this topic with particular focus on current limitations and modelling of LID uncertainty correlations.

Speaker: Kenta Uno (KEK)

2023.10.31_Kuno_PhysicsWeek.pdf

18:30 → 21:00 Party

Wednesday, 1 November

08:30 → 12:45 School

SpeakApp

08:30 Flavour physics 3

Speaker: Dr Rusa Mandal (IIT Gandhinagar)

09:45 FEI: from top-to-bottom

Speaker: Niharika Rout (INFN Trieste)

FEI_PhyWeek_NR_v2.pdf

11:00 Coffee

11:30 Belle + Belle II analyses: a how to guide?

Speaker: Xiaodong Shi (BELLE (BELLE II Experiment))

HowToB1B2Ana-V3.pdf

10:00 → 11:00 Setting up the KEK report

WorkshopDocument.pdf

13:45 → 16:15 Workshop: Vcb inclusive

Convener: Rusa Mandal (IITGN)

13:45 Experimental developments of inclusive inputs

Review of Belle/Belle II most recent measurements (q2 moments). 
Measurement of BR(B->Xc l nu) and other going/planned activities on Belle II: Mx, El moments from previous measurements can be updated using Belle II data; angular moments measurement is ongoing. Status, issues and needs for a new determination of the inclusive measurements (e.g. w/ q2 thresholds, approach for handling syst.).

Speaker: Lu Cao (BELLE (BELLE Gruppe))

Vcb2023_LuCao.pdf

14:15 Vub/Vcb inclusive measurement

Recent Belle result (first BRs ratio measurement from inclusive decays) and prospects for the decay-width-ratio calculation (a part of th. error can be cancelled in ratio)

Speakers: Marcel Hohmann (BELLE (BELLE II Experiment)), Dr Phillip Urquijo (The University of Melbourne)

MHohmann_Belle2_physics_week_2023.pdf

14:50 Vub/Vcb from lattice

Lattice calculation of relevant form factors and future prospects

Speaker: Judd Harrison (Glasgow)

outline.pdf

Vcb_Vub_from_lattice.pdf

15:20 Theory progress for Vcb inclusive

|Vcb| from q2 moments [JHEP 10, 068 (2022) ], BR(B->Xc l nu) is needed. Recent theoretical results on kin. moments including NP impacts [JHEP 02, 086 (2023)].

Exp wish-list from th. experts:

- recommended phase space region, kinematic threshold

- further needed exp. inputs 

- what’s beyond moments?

Speaker: Keri Vos

Vcb_inclusive_KEK.pdf

16:15 → 16:45 Coffee break

16:45 → 18:30 Workshop discussion: Break out

Conveners: Florian Bernlochner (Belle (SuperKEKB Experiment)), Paolo Gambino (Torino)

16:45 Discussion items

Speakers: Florian Bernlochner (Belle (SuperKEKB Experiment)), Paolo Gambino (Torino)

Vcb Workshop Discussion Items.pdf

18:30 → 20:00 Poster session (sake and otsumami)

Thursday, 2 November

08:30 → 12:45 School

SpeakApp

08:30 Systematics uncertainties: an introduction

Speaker: Bruce Yabsley (BELLE (BELLE II Experiment))

physics-week-202311-systematics-yabsley-final.pdf

09:45 Lepton identification: an overview

Speaker: Kenta Uno (KEK)

2023.11.02-PhysicsWeek_kuno.pdf

11:00 Coffee

11:30 A view from the otherside: semileptonics at LHCb

Speaker: Patrick Owen Powen (UZH)

SLatLHCb.pdf

13:45 → 15:15 Workshop: Vcb inclusive

Convener: Lu Cao (BELLE (BELLE Gruppe))

13:45 Loops in inclusive determination

Speaker: Matteo Fael (CERN)

Fael_BelleII2023.pdf

14:20 Challenges for a global inclusive analysis

Status (only Mx and El moments used), pros/cons of leptonic and hadronic moments. Would a global analysis ever be possible (and useful)? Guidance towards a global analysis -> fit OPE parameters, quark masses, BR

Speaker: Marzia Bordone (CERN)

Bordone_KEK.pdf

15:15 → 16:15 Tools

Convener: Lu Cao (BELLE (BELLE Gruppe))

15:15 HAMMER and eFFORT

Discuss any recent ore foreseen developments and needs from analyst (can also collect inputs in advance from Belle 2 people if needed)

Speaker: Michele Papucci (CALTECH)

Hammer KEK 2023.pdf

15:45 New EvtGen models for D*lnu

Discuss https://arxiv.org/abs/2203.07189

Speaker: Lopamudra Mukherjee

EvtGen_Talk.pdf

Lopa-Tools-Talk-Outline.pdf

16:15 → 16:45 Coffee break

16:45 → 17:30 Workshop discussion: Vcb combinations

Convener: James Frederick Libby (BELLE (BELLE II Experiment))

16:45 Discussion items

Speaker: James Frederick Libby (BELLE (BELLE II Experiment))

Physics week - Vcb combo discussion.pdf

17:30 → 18:30 Workshop: Prospects and closing

Convener: James Frederick Libby (BELLE (BELLE II Experiment))

17:30 Vcb in 3 years and beyond

Prospecst for Vcb and what we would like to have in 3 years (possibly taking also inputs from the discussion during the workshop)

Speaker: Paolo Gambino (Torino)

kek.pdf

18:15 Closing

Speaker: Karim Trabelsi (IJCLab (Orsay))

Friday, 3 November

08:30 → 13:15 School

SpeakApp

09:00 E_ECL: what it is and how to use it

Speaker: Gaetano de Marino (Jožef Stefan Institute)

ecltalk v3.pdf

10:15 Hands-on reports 1 - E_ECL pi0 veto

Speaker: Niharika Rout (INFN Trieste)

PhyWeekChallenge_NR_sol.pdf

10:25 Hands on report 2 - rhorho interference

Speaker: Riccardo Manfredi (BELLE (BELLE II Experiment))

PW_challenge.pdf

10:35 Hands on three - fragmentation

Speaker: Junewoo Park (University of Tokyo (BELLE II Experiment))

handson_20231103.pdf

10:45 Hands-on 4 -flavour tagger

Speaker: Sebastiano Raiz (BELLE (BELLE II Experiment))

1SlideChallengeRaizResults.pdf

1SlideChallengeRaiz_v2.pdf

10:55 Hands on 5 - statistics

Speaker: Xiaodong Shi (BELLE (BELLE II Experiment))

StatIssueInPhi3ComboV1.pdf

11:05 Coffee