Neutral Kaon Spectrometer 2

TL;DR

NKS2 is a newly built large-acceptance spectrometer at Tohoku University designed to study photoproduction reactions involving strangeness in the gigaelectronvolt energy range, with detailed detector performance and experimental results.

Contribution

The paper introduces the design, construction, and performance of NKS2, a novel spectrometer for strangeness photoproduction experiments in the gigaelectronvolt region.

Findings

Successful separation of pions and protons up to 1 GeV/$c$

First analysis of strangeness photoproduction data with NKS2

Validation of detector performance in experimental conditions

Abstract

A large-acceptance spectrometer, Neutral Kaon Spectrometer 2 (NKS2), was newly constructed to explore various photoproduction reactions in the gigaelectronvolt region at the Laboratory of Nuclear Science (LNS, currently ELPH), Tohoku University. The spectrometer consisted of a dipole magnet, drift chambers, and plastic scintillation counters. NKS2 was designed to separate pions and protons in a momentum range of less than 1 GeV/$c$, and was placed in a tagged photon beamline. A cryogenic H$_{2}$/D$_{2}$ target fitted to the spectrometer were designed. The design and performance of the detectors are described. The results of the NKS2 experiment on analyzing strangeness photoproduction data using a 0.8--1.1 GeV tagged photon beam are also presented.