https://doi.org/10.1140/epja/i2016-16259-x
Regular Article - Experimental Physics
Diphoton and dipion productions at the Nuclotron/NICA
1
VBLHEP JINR, 141980, Dubna, Moscow region, Russia
2
International Center for Advanced Studies, YSU, 0025, Yerevan, Armenia
3
Institute of Applied Physics, MD-2028, Kishinev, Moldova
4
Institute of Nuclear Physics, Moscow State University, 119992, Moscow, Russia
5
Institut für Theoretische Physik, Universität Tübingen, Auf der Morgenstelle 14, D-72076, Tübingen, Germany
6
Moscow State Institute of Radioengineering, Electronics and Automation, 119454, Moscow, Russia
7
BLTP JINR, 141980, Dubna, Moscow region, Russia
* e-mail: abraam@sunhe.jinr.ru
Received:
15
October
2015
Accepted:
10
March
2016
Published online:
24
August
2016
Along with 
and 
mesons, a resonance structure in the invariant-mass spectrum of two photons at 
MeV is observed in the reaction 
at momentum 2.75GeV/c per nucleon. Estimates of its width and production cross section are 
MeV and 
μb, respectively. The collected statistics amount to 
events of 
triggered interactions of a total number 
of 
interactions. This resonance structure is not observed in the 
channel in 
collisions at the beam momentum 5.5GeV/c . The result obtained in the reaction 
is confirmed by the second experiment carried out on the deuteron beam at momentum 3.83GeV/c per nucleon with a copper target: 
MeV, 
MeV and 
μb. Some results on the observation of the resonance in the invariant-mass spectra of two mesons are presented: the data obtained in the 
reaction is confirmed by the results for the 
and 
reactions; a preliminary estimate of the ratio 
is 
. Further studies of this resonance is assumed at the Nuclotron/NICA at higher setup acceptance, which will allow to elucidate the nature of this resonance by determination of the differential cross sections at different beam energies in the range 1-6GeV/n and the mechanism of its formation.
© SIF, Springer-Verlag Berlin Heidelberg, 2016
