Hadron loops effect on mass shifts of the charmed and charmed-strange spectra

TL;DR

This paper investigates how hadron loop effects influence the mass shifts of charmed and charmed-strange mesons, improving theoretical predictions and explaining mixing phenomena, with some unresolved issues.

Contribution

It introduces an accessible method to incorporate hadron loop effects, demonstrating their role in reducing mass discrepancies and explaining state mixing in charmed mesons.

Findings

Hadron loop effects shift meson masses downward.

The method improves agreement with experimental mass and width data.

Explains $1^1P_1-1^3P_1$ mixing via common channel couplings.

Abstract

The hadron loop effect is conjectured to be important in understanding discrepancies between the observed states in experiments and the theoretical expectations of non-relativistic potential model. We present that, in an easily operable procedure, the hadron loop effect could shift the poles downwards to reduce the differences and provide better descriptions of both the masses and the total widths, at least, of the radial quantum number $n=1$ charmed and charmed-strange states. The $1^1P_1-1^3P_1$ mixing phenomena could be naturally explained due to their couplings with common channels. The newly observed $D$ states are also addressed, but there are still some problems remaining unclear.