Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

$DD^*$ correlation functions in deciphering the nature of $T_{cc}(3875)^+$

Duo-Lun Ge, Zhi-Wei Liu, Li-Sheng Geng

Abstract

Understanding near-threshold strong interactions is essential for disentangling hadronic molecules and compact multiquark states in heavy-flavor spectroscopy. In this context, the doubly charmed tetraquark candidate $T_{cc}(3875)^+$ serves as a critical benchmark because it lies very close to the $D^*$-$D$ thresholds. Motivated by the interaction ambiguity reported recently [\href{https://doi.org/10.1103/kd4s-9rzr}{Phys.Rev.D 113, L031505 (2026)}], we evaluate the $D^*$-$D$ scattering lengths and femtoscopic correlation functions for the molecular and molecule-compact admixture assignments of the $T_{cc}(3875)^+$. We show that, although these scenarios yield similar invariant-mass line shapes, their corresponding femtoscopic correlation functions differ markedly and remain clearly distinguishable for typical particle-emitting sources created at the LHC. Our results indicate that femtoscopy can serve as a sensitive and complementary probe of the near-threshold dynamics of $T_{cc}(3875)^+$, providing vital theoretical references for future LHC femtoscopy measurements.

$DD^*$ correlation functions in deciphering the nature of $T_{cc}(3875)^+$

Abstract

Understanding near-threshold strong interactions is essential for disentangling hadronic molecules and compact multiquark states in heavy-flavor spectroscopy. In this context, the doubly charmed tetraquark candidate serves as a critical benchmark because it lies very close to the - thresholds. Motivated by the interaction ambiguity reported recently [\href{https://doi.org/10.1103/kd4s-9rzr}{Phys.Rev.D 113, L031505 (2026)}], we evaluate the - scattering lengths and femtoscopic correlation functions for the molecular and molecule-compact admixture assignments of the . We show that, although these scenarios yield similar invariant-mass line shapes, their corresponding femtoscopic correlation functions differ markedly and remain clearly distinguishable for typical particle-emitting sources created at the LHC. Our results indicate that femtoscopy can serve as a sensitive and complementary probe of the near-threshold dynamics of , providing vital theoretical references for future LHC femtoscopy measurements.

Paper Structure

This paper contains 6 sections, 8 equations, 6 figures, 1 table.

Table of Contents

  1. Introduction
  2. Theoretical Formalism
  3. Results and discussions
  4. $DD^*$ interactions
  5. Correlation functions
  6. Summary and outlook

Figures (6)

  • Figure 1: Coupled-channel femtoscopic correlation functions for the $D^{*+}$-$D^0$ channel (channel 1) as functions of the relative momentum $k$, computed for three scenarios: Mol.+Compact (left), Mol. 1 (middle), and Mol. 2 (right). The source radii are taken as $R=1$ fm (dashed), $2$ fm (dash-dotted), and $5$ fm (solid), and the momentum cutoff is set to $q_{\max}=0.5$ GeV/$c$. See the main text for more details.
  • Figure 2: Same as Fig. \ref{['Fig:coupled_CF_channel1']}, but for the $D^{*0}$-$D^+$ channel (channel 2).
  • Figure 3: Comparison between coupled-channel and single-channel CFs for the $D^{*+}$-$D^0$ system for $R=3$ fm ($q_{\max}=0.5$ GeV/$c$), shown for Mol.+Compact (left), Mol. 1 (middle), and Mol. 2 (right). Solid curves denote coupled-channel results, while dashed curves show the corresponding single-channel calculations with the other channel switched off.
  • Figure 4: Same as Fig. \ref{['Fig:coupled_CF_VS_single_CF_channel1']}, but for the $D^{*0}$-$D^+$ system for $R=3$ fm.
  • Figure 5: Comparison between CFs for the $D^{*+}$-$D^0$ system for $R=1$ fm ($q_{\max}=0.5$ GeV/$c$). The solid and dashed curves denote Mol. 1 and Mol. 2 results calculated in this work, respectively. The dotted and dash-dotted curves show the corresponding results of Ref. Kamiya:2022thy and Ref. Vidana:2023olz, respectively.
  • ...and 1 more figures