Based on (2712.4±14.1)×106 ψ(2S) events, 7.9 fb-1 ψ(3773) data, and 0.8 fb-1 off-resonance data samples collected with the BESIII detector, we measure the branching fraction of ψ(2S)→γπ0 and e+e-→γπ0 form factor at momentum transfers Q2∼13 GeV2. The e+e-→γπ0 cross section is fitted with considering the interference between the ψ(2S) and continuum amplitudes and two solutions are found, B=3.74×10-7 with φ=3.93 rad and B=7.87×10-7 with φ=2.08 rad. Here, B is the branching fraction of ψ(2S)→γπ0 and φ is the relative phase angle between the ψ(2S) and continuum amplitudes. Due to insufficient off-resonance data, the branching fraction B(ψ(2S)→γπ0) is determined to be in the range [2.7,9.7]×10-7 within 1 standard deviation of the contour region.

Measurement of the branching fraction of ψ(2S)→γπ0

Amoroso, A.;Bianchi, F.;Bortone, A.;Destefanis, M.;De Mori, F.;Greco, M.;Lavezzi, L.;Maggiora, M.;Marcello, S.;Sosio, S.;Spataro, S.;
2024-01-01

Abstract

Based on (2712.4±14.1)×106 ψ(2S) events, 7.9 fb-1 ψ(3773) data, and 0.8 fb-1 off-resonance data samples collected with the BESIII detector, we measure the branching fraction of ψ(2S)→γπ0 and e+e-→γπ0 form factor at momentum transfers Q2∼13 GeV2. The e+e-→γπ0 cross section is fitted with considering the interference between the ψ(2S) and continuum amplitudes and two solutions are found, B=3.74×10-7 with φ=3.93 rad and B=7.87×10-7 with φ=2.08 rad. Here, B is the branching fraction of ψ(2S)→γπ0 and φ is the relative phase angle between the ψ(2S) and continuum amplitudes. Due to insufficient off-resonance data, the branching fraction B(ψ(2S)→γπ0) is determined to be in the range [2.7,9.7]×10-7 within 1 standard deviation of the contour region.
2024
110
5
1
12
Ablikim, M.; Achasov, M. N.; Adlarson, P.; Afedulidis, O.; Ai, X. C.; Aliberti, R.; Amoroso, A.; An, Q.; Bai, Y.; Bakina, O.; Balossino, I.; Ban, Y.; ...espandi
File in questo prodotto:
File Dimensione Formato  
PhysRevD.110.052011.pdf

Accesso aperto

Dimensione 669.55 kB
Formato Adobe PDF
669.55 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/2069295
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? ND
social impact