LHCb meets Theory: Probing the nature of the $X(3872)$ state using radiative decays

Thursday 27 Jun 2024, 00:40 → 19:30 Europe/Zurich

17/1-007 (CERN)

Lorenzo Capriotti (Universita e INFN, Ferrara (IT)), Mengzhen Wang (Università degli Studi e INFN Milano (IT)), Vanya Belyaev (Sapienza Universita e INFN, Roma I (IT))

This is a traditional mini-worshop "LHCb meets Theory". Previous editions of this workshop were devoted to  studies of charm abd beauty baryons,, double-heavy baryons, lineshape of the X(3872) state,  double open charm tetraquark $T_{cc}^+$, prospects for the $T_{bc}$ and $T_{bb}$ tetraquarks and many other hot items, interesting both for the LHCb and Theory. 

This edition is devoted to probing of the nature of the $X(3872)$ state using radiative decays. The nature of the $X(3872)$ state is a subject of hot discussinon and intensive studies for more than twenty years.  Radiative decays, namely the ratio of the partial widths of the $X(3872)$ decays into the $\psi^{\prime}\gamma$ and $J/\psi\gamma$ final state potentially could shed light on the nature of the  $X(3872)$ state, since the predicted ratio of  radiative width is very sensitive to the assumed $X(3872)$ structure. The experimental situation (May 2024) is rather controversial, and there is no theory consensus. This worskhop provide the opportunity to discuss both theoretical and experiemtnal issues. 

Recent LHCb results on the analysis of funr Run1 and Run2 datasets (2011-2018) have been reported at the CERN seminar, June 11, 2024  and appeared at arXiv at June 26, 24 

 

1 Welcome and introduction

Speakers: Lorenzo Capriotti (Universita e INFN, Ferrara (IT)), Mengzhen Wang (Università degli Studi e INFN Milano (IT)), Vanya Belyaev (Sapienza Universita e INFN, Roma I (IT))

20240627-X3872-Intro.pdf

20240627-X3872-Intro.pptx

2 Predicting isovector charmonium-like states from X(3872) properties

Speaker: Prof. Feng-Kun Guo (Insitute of Theoretical Physics, Chinese Academy of Sciences)

IsovectorX_FKGuo.pdf

3 Radiative decay of X(3872) at BESIII”

Speaker: Yin Junhao

10:40 Coffee/tea break

4 X(3872) radiative decays: View from molecular side

Speakers: Alexey Nefediev (ITEP), Dr Alexey Nefediev (LPI, Moscow, Russia), Christoph Hanhart, Prof. Feng-Kun Guo (Insitute of Theoretical Physics, Chinese Academy of Sciences)

x3872-rad.pdf

5 Belle and Belle II status and plans for radiative decays of the X(3872)

Speaker: Dr Vishal Bhardwaj (IISER Mohali)

Bhardwaj_TheoryMeetLHCb2024_vF.pdf

6 Probing the nature of the $\chi_{c1}(3872)$ state with its radiative decays at LHCb

Speaker: Vanya Belyaev (Sapienza Universita e INFN, Roma I (IT))

20240627-X3872-LHCb.pdf

20240627-X3872-LHCb.pptx

LHCb-PAPER-2024-015

supplementary.pdf

12:30 Lunch break

7 Radiative decays of compact tetraquark

Speakers: Antonio Davide Polosa (Sapienza University of Rome), Antonio Davide Polosa, Antonio Polosa (Universita' La Sapienza, Roma - Italy), Benjamin Grinstein (Univ. of California San Diego (US)), Luciano Maiani (Sapienza Universita e INFN, Roma I (IT))

8 Radiative decays of the X(3872) in the charmonium-molecule hybrid picture

Speaker: Sachiko Takeuchi (Japan College of Social Work)

15:00 Coffee/tea break

9 Probing the structure of $X(3872)$ with radiative decays: heavy quark symmetries at work

Speaker: Fulvia De Fazio

defazio.pdf

10 Tetraquarks

Speakers: Luciano Maiani (Sapienza Universita e INFN, Roma I (IT)), Luciano Maiani (Unknown)

Tetraqs.pdf

11 Interpreting the X

Speaker: Eric Swanson

X3872redux.pdf