The Dπ and D*π femtoscopy puzzle
Abstract
We present a relativistic momentum-space framework for femtoscopic correlation functions including strong and Coulomb interactions in coupled channels. The approach extends the Vincent--Phatak prescription to the three-dimensional Bethe--Salpeter equation, combining a fully relativistic treatment with the correct Coulomb asymptotics through wave-function matching. We apply it to the Dπ system using a coupled-channel heavy-meson chiral interaction that reproduces the established two-pole structure of the D0*(2300). Our correlation functions agree with previous theoretical calculations but differ significantly from those extracted by the ALICE Collaboration. We trace this tension to the assumption made in the experimental analysis that the genuine correlation function reaches unity above a relative momentum of $100$ MeV, whereas this region remains affected by the lower D0*(2300) pole. Repeating the extraction over different fitting windows reveals a strong dependence of the extracted signal on the chosen range, demonstrating that the resulting Dπ scattering parameters are not robust and motivating a dedicated reanalysis of the experimental data. We extend the analysis to the D*π system, where the same issue arises in close connection with heavy-quark spin symmetry. Together with the unresolved tension between theoretical calculations and the ALICE Kπ femtoscopic measurements, this highlights the need to clarify the origin of this puzzle, with the aim of establishing femtoscopy as a reliable quantitative tool for precision studies of low-energy hadron interactions.
Related
- Coulomb effects in momentum-space femtoscopy: A case study of the K‾Ω system
- Extraction of All Partial-Wave Interaction Parameters via Femtoscopy: The Central-Force Case
- Three-baryon femtoscopy as an effective 3→3 scattering experiment
- Search for 4Li̅ from p̅+3He̅ femtoscopy in Pb-Pb collisions at √(sNN) =5.36 TeV with ALICE
- Charmonium-nucleon femtoscopy as a possible probe of the nucleon gravitational form factor
BibTeX
@misc{encarnacion2026femtoscopy,
title = {{The $Dπ$ and $D^*π$ femtoscopy puzzle}},
author = {Pablo Encarnación and Miguel Albaladejo and Albert Feijoo and Juan Nieves},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.35133},
eprint = {2609.35133},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.35133},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - The Dπ and D^*π femtoscopy puzzle
AU - Pablo Encarnación
AU - Miguel Albaladejo
AU - Albert Feijoo
AU - Juan Nieves
PY - 2026
DA - 2026/09/28
PB - arXiv
DO - 10.48550/arxiv.2609.35133
UR - https://arxiv.org/abs/2609.35133
AB - We present a relativistic momentum-space framework for femtoscopic correlation functions including strong and Coulomb interactions in coupled channels. The approach extends the Vincent--Phatak prescription to the three-dimensional Bethe--Salpeter equation, combining a fully relativistic treatment with the correct Coulomb asymptotics through wave-function matching. We apply it to the Dπ system using a coupled-channel heavy-meson chiral interaction that reproduces the established two-pole structure of the D_0^*(2300). Our correlation functions agree with previous theoretical calculations but differ significantly from those extracted by the ALICE Collaboration. We trace this tension to the assumption made in the experimental analysis that the genuine correlation function reaches unity above a relative momentum of $100$ MeV, whereas this region remains affected by the lower D_0^*(2300) pole. Repeating the extraction over different fitting windows reveals a strong dependence of the extracted signal on the chosen range, demonstrating that the resulting Dπ scattering parameters are not robust and motivating a dedicated reanalysis of the experimental data. We extend the analysis to the D^*π system, where the same issue arises in close connection with heavy-quark spin symmetry. Together with the unresolved tension between theoretical calculations and the ALICE Kπ femtoscopic measurements, this highlights the need to clarify the origin of this puzzle, with the aim of establishing femtoscopy as a reliable quantitative tool for precision studies of low-energy hadron interactions.
ER -