Photoproduction of the f2 (1270) Meson Using the CLAS Detector

Abstract

The quark structure of the f2(1270) meson has, for many years, been assumed to be a pure quark-antiquark (qq¯) resonance with quantum numbers JPC=2++. Recently, it was proposed that the f2(1270) is a molecular state made from the attractive interaction of two ρ mesons. Such a state would be expected to decay strongly to final states with charged pions due to the dominant decay ρ→π+π-, whereas decay to two neutral pions would likely be suppressed. Here, we measure for the first time the reaction γp→π0π0p, using the CEBAF Large Acceptance Spectrometer detector at Jefferson Lab for incident beam energies between 3.6 and 5.4 GeV. Differential cross sections, dσ/dt, for f2(1270) photoproduction are extracted with good precision due to low backgrounds and are compared to theoretical calculations.

Metadata

Funding Information: The authors thank Professor J-J. Xie and Professor E. Oset for providing us the cross-section predictions from the model described in Ref. for the energy and momentum-transfer range covered by the data presented in this Letter. The authors acknowledge the staff of the Accelerator and Physics Divisions at the Thomas Jefferson National Accelerator Facility who made this experiment possible. This work was supported in part by the Chilean Comisión Nacional de Investigación Científica y Tecnolgica (CONICYT), by CONICYT PIA Grant No. ACT1413, the Italian Istituto Nazionale di Fisica Nucleare, the French Centre National de la Recherche Scientifique, the French Commissariat á lEnergie Atomique, the United Kingdom Science and Technology Facilities Council (STFC), the Scottish Universities Physics Alliance (SUPA), the National Research Foundation of Korea, and the U.S. National Science Foundation. V. M. acknowledges support from the Community of Madrid through the Programa de Atracción de Talento Investigador 2018-T1/TIC-10313 and from the Spanish national Grant No. PID2019–106080 GB-C21. The Southeastern Universities Research Association operates the Thomas Jefferson National Accelerator Facility for the U.S. Department of Energy under Contract No. DE-AC05-06OR23177. Publisher Copyright: © 2021 American Physical Society.

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