An alternative fit to Belle mass spectra for DD, D*D* and Lambda_C Lambda_c

TL;DR

This paper proposes an alternative fitting method for Belle's observed mass spectra in various charmed baryon and meson pairs, using phase space and form factors to explain the peaks.

Contribution

It introduces a new fitting approach employing form factors with specific RMS radii to interpret observed spectral peaks.

Findings

Peaks in DD and D*D* spectra can be fitted with form factors of 0.63 fm and 0.94 fm.

The Lambda_C Lambda_C peak at 4.63 GeV can be explained by the Y(4660) resonance.

The method provides a consistent explanation for multiple observed spectral features.

Abstract

Peaks observed by Belle in DD at 3.878 GeV and in D*D* at 4.156 GeV may be fitted by phase space multiplied by a form factor with an RMS radius of interaction 0.63 fm. The peak observed in Lambda_C Lambda_C at 4.63 GeV may be explained by Y(4660), multiplied by a corresponding form factor with RMS radius 0.94 fm.