Authors:	Deineka, Oleksandra Danilkin, Igor Vanderhaeghen, Marc
Title:	Dispersive analysis of the γγ → DD¯ data and the confirmation of the DD¯ bound state
Online publication date:	14-Apr-2023
Year of first publication:	2022
Language:	english
Abstract:	In this paper, we present a data-driven analysis of the γγ → D+ D− and γγ → D0D¯ 0 reactions from threshold up to 4.0 GeV in the DD¯ invariant mass. For the S-wave contribution, we adopt a partial-wave dispersive representation, which is solved using the N/D ansatz. The left-hand cuts are accounted for using the model-independent conformal expansion. The D-wave χc2(3930) state is described as a BreitWigner resonance. The resulting fits are consistent with the data on the invariant mass distribution of the e+e− → J/ψ DD¯ process. Performing an analytic continuation to the complex s-plane, we find no evidence of a pole corresponding to the broad resonance X(3860) reported by the Belle Collaboration. Instead, we find a clear bound state below the DD¯ threshold at √sB = 3695(4) MeV, confirming the previous phenomenological and lattice predictions.
DDC:	530 Physik 530 Physics
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 08 Physik, Mathematik u. Informatik
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-8913
Version:	Published version
Publication type:	Zeitschriftenaufsatz
Document type specification:	Scientific article
License:	CC BY
Information on rights of use:	https://creativecommons.org/licenses/by/4.0/
Journal:	Physics letters : B 827
Pages or article number:	136982
Publisher:	Elsevier
Publisher place:	Amsterdam
Issue date:	2022
ISSN:	1873-2445
Publisher DOI:	10.1016/j.physletb.2022.136982
Appears in collections:	DFG-491381577-D