Abstract
A Σ⁎ resonance with spin-parity JP=1/2− and mass in the vicinity of the K¯N threshold has been predicted in the unitary chiral approach and inferred from the analysis of CLAS data on the γp→K+π0Σ0 reaction. In this work, based on the dominant Cabibbo favored weak decay mechanism, we perform a study of Λc+→π+π0Σ⁎ with the possible Σ⁎ state decaying into π−Σ+ through a triangle diagram. This process is initiated by Λc+→π+K¯⁎N, then the K¯⁎ decays into K¯π and K¯N produce the Σ⁎ through a triangle loop containing K¯⁎NK¯ which develops a triangle singularity. We show that the π−Σ+ state is generated from final state interaction of K¯N in S-wave and isospin I=1, and the Λc+→π+π0π−Σ+ decay can be used to study the possible Σ⁎ state around the K¯N threshold. The proposed decay mechanism can provide valuable information on the nature of the Σ⁎ resonance and can in principle be tested by facilities such as LHCb, BelleII and BESIII.
Highlights
Investigating low-lying excited states of (1193), ∗, with isospin I = 1 and strangeness S = −1 is one of the important issues in hadronic physics [1,2,3]
Such a state near the K N threshold is discussed in Refs. [11,12], while in Ref. [15], a ∗ state is found with mass around 1400 MeV, though it is not clear if it is related to one or two poles in the complex plane
The triangle singularities have recently shown to be very important in many hadronic decays
Summary
[10] as a strong cusp effect [16] based on the analysis of the experimental data on the γ p → K +π ± ∓ reactions [17,18] Such a state near the K N threshold is discussed in Refs. The effect of this possible K N state with mass about 1430 MeV in the processes of χc0(1P ) → π ( ) decays was studied in Refs. The TS appears from a loop diagram in the decay of a particle 1 into two particles 2 and 3 through the following process: at first the particle 1 decays into particles A and B, and the particle A subsequently decays into particles 2 and C , and the particles B and C merge and form the particle 3 in the final state.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
