Work

Investigating the two-pion exchange of the double charm D D * chiral interactions and T c c

Year: 2025

Type: article

Abstract: Under chiral effective field theory, we study the S -wave D D * interactions up to second chiral order at one-loop level, which contain full contact, one-pion-exchange (OPE) and two-pion-exchange (TPE) contributions. Here, we adopt a new subtraction scheme of the two-particle-reducible contributions and attempt different regularization schemes uniquely for the TPE contributions since they are highly divergent on the momentum transfer. Under these schemes, we conclude that, in the I = 0 channel, the TPE contribution is repulsive, then the competition between this powerful repulsing TPE and the other two (contact and OPE) results in a quite weak attraction. This explains why T c c has an extremely small binding energy if treated as the I = 0 D D * bound state. This feature resembles that of hidden charm D D ¯ * as we investigated in previous work [], which also interpreted the extremely near-threshold phenomenon of X ( 3872 ) . In addition, we also solve the Bethe-Salpeter equation with the chiral interactions for a consistency check.

Source: Physical review. D/Physical review. D.

DOI: 10.1103/gryg-xtt4

Authors: Hao Xu, Li-Xiang Ren

Institution: Northwest Normal University

Language: English

Topic: Quantum Chromodynamics and Particle Interactions

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Funders: National Natural Science Foundation of China, Natural Science Foundation of Gansu Province

Awards: G1082000272, G3609874351, G5425351251