The Zcs(3985) as a threshold effect from the D¯s⁎D+D¯sD⁎ interaction

• Main Authors: Natsumi Ikeno, Raquel Molina, Eulogio Oset
• Format: Article
• Language: English
• Published: Elsevier 2021-03-01
• Series: Physics Letters B
• Online Access: http://www.sciencedirect.com/science/article/pii/S0370269321000605

We study the e+e−→K+(Ds⁎−D0+Ds−D⁎0) reaction recently measured at BESIII, from where a new Zcs state has been reported. We study the interaction of D¯sD⁎ with the coupled channels J/ψK−, K⁎−ηc, Ds−D⁎0, Ds⁎−D0 by means of an extension to the charm sector of the local hidden gauge approach. We find that the Ds−D⁎0+Ds⁎−D0 combination couples to J/ψK− and K⁎−ηc, but the Ds−D⁎0−Ds⁎−D0 combination does not. The coupled channels help to build up strength in the Ds−D⁎0+Ds⁎−D0 diagonal scattering matrix close to threshold and, although the interaction is not strong enough to produce a bound state or resonance, it is sufficient to produce a large accumulation of strength at the D¯sD⁎ threshold in the e+e−→K+(Ds⁎−D0+Ds−D⁎0) reaction in agreement with experiment.