Neutral meson production in pp and Pb–Pb collisions measured by ALICE at the LHC

Abstract Generalised Parton Distributions (GPDs) offer a way of imaging nucleons through 3D tomography. They can be accessed experimentally in processes such as Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Production (DVMP), where a high energy electron scatters from a quark inside a nucleon and a high energy photon or meson is produced as a result. Jefferson Lab has recently completed its energy upgrade and Hall B houses the new, large-acceptance CLAS12 detector array optimised for measurements of DVCS and DVMP in the newly accessible kinematic regime. Measurements on the proton and neutron are complementary and both are necessary to facilitate access to the full set of GPDs and enable their flavour separation. Neutron DVCS and DVMP are possible with the use of a deuteron target – the first CLAS12 experiment with which has started taking data this year. To enable exclusive reconstruction of DVCS and neutral-meson DVMP, a dedicated detector for recoiling neutrons – the Central Neutron Detector (CND) – was integrated into CLAS12. We present the first CLAS12 deuteron-target experiment, with a focus on the performance of the CND.

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Neutral meson production in Cu+Au collisions at 200 GeV

Journal of Physics Conference Series ◽

10.1088/1742-6596/929/1/012061 ◽

2017 ◽

Vol 929 ◽

pp. 012061

Author(s):

A. Berdnikov ◽

Ya. Berdnikov ◽

D. Kotov ◽

P. Radzevich ◽

V. Riabov ◽

...

Keyword(s):

Meson Production ◽

Neutral Meson ◽

200 Gev

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On a phenomenological approach to meson production in nucleon-nucleon collisions

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1951.0232 ◽

1951 ◽

Vol 210 (1100) ◽

pp. 85-98 ◽

Cited By ~ 1

Keyword(s):

Meson Production ◽

Phenomenological Approach ◽

Nucleon Nucleon ◽

Neutral Meson ◽

No Production ◽

Distorted Wave ◽

Proton Proton ◽

Neutral Mesons ◽

Valid Comparison ◽

Charged Mesons

The validity of certain phenomenological approaches to spin zero meson production in nucleon-nucleon collisions is considered. It is shown that, to first-order perturbation theory, a method analogous to the distorted wave approximation is valid. Comparison is made with a bremsstrahlung-like calculation which, for neutral mesons with non-derivative coupling to the spinor field, gives no production, since the nucleon recoil is neglected. Application of the distorted wave approach to neutral meson production in proton-neutron collisions, and comparison with the results for production of charged mesons in proton-proton collisions is sketched. Results are quoted for simple inverse processes.

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