Momentum dependence of the phi-meson nuclear transparency

TL;DR

This study investigates how the nuclear transparency and in-medium properties of phi mesons vary with momentum in proton-nucleus collisions, revealing a significant momentum dependence and estimating the phi-N absorption cross section.

Contribution

First measurement of momentum dependence of phi meson nuclear transparency, in-medium width, and production cross section across multiple targets at COSY.

Findings

Indications of a significant momentum dependence in phi width.

Estimated phi-N absorption cross section between 14 and 21 mb.

First determination of these properties over the specified momentum range.

Abstract

The production of phi mesons in proton collisions with C, Cu, Ag, and Au targets has been studied via the phi -> K+K- decay at an incident beam energy of 2.83 GeV using the ANKE detector system at COSY. For the first time, the momentum dependence of the nuclear transparency ratio, the in-medium phi width, and the differential cross section for phi meson production at forward angles have been determined for these targets over the momentum range of 0.6 - 1.6 GeV/c. There are indications of a significant momentum dependence in the value of the extracted phi width, which corresponds to an effective phi-N absorption cross section in the range of 14 - 21 mb.