The two-step mechanism explaning the dibaryon “d ∗ (2380)” peak

Authors

  • Raquel Molina Peralta IFIC-UV
  • E. Oset Centro Mixto Universidad de Valencia-CSIC
  • N. Ikeno Tottori University

DOI:

https://doi.org/10.31349/SuplRevMexFis.3.0308029

Keywords:

Dibaryon, hexaquark, two-nucleon fusion

Abstract

In this talk we show that the two-step sequential one pion production mechanism, np(I = 0) → π −pp, followed by the fusion reaction pp → π +d, can explain the narrow peak identified with a “d ∗ (2380)” dibaryon in the np → π +π −d reaction with π +π − in I = 0. We demonstrate that the second step pp → π +d is driven by a triangle singularity that determines the position of the peak of the reaction and the large strength of the cross section. The combined cross section of these two mechanisms produce a narrow peak with the position, width and strength compatible with the experimental observation within the approximations done. This novel interpretation of the peak without invoking a dibaryon explains why the peak is not observed in other reactions where it has been searched for.

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Published

2022-05-25

How to Cite

1.
Molina Peralta R, Oset E, Ikeno N. The two-step mechanism explaning the dibaryon “d ∗ (2380)” peak. Supl. Rev. Mex. Fis. [Internet]. 2022 May 25 [cited 2022 Dec. 7];3(3):0308029 1-6. Available from: https://rmf.smf.mx/ojs/index.php/rmf-s/article/view/6253