The Polarized H and D Atomic Beam Source for ANKE at COSY-J\"ulich

TL;DR

This paper reports the development of a polarized atomic beam source for the ANKE spectrometer at COSY-J"ulich, achieving high polarization and intensity for hydrogen and deuterium beams used in nuclear physics experiments.

Contribution

It introduces a new polarized atomic beam source with high polarization and intensity for hydrogen and deuterium at COSY-J"ulich, including detailed technical design and performance data.

Findings

Hydrogen beam intensity of 7.5×10^{16} atoms/s with ~92% polarization.

Deuterium beam intensity of 3.9×10^{16} atoms/s with high vector and tensor polarizations.

Achieved specific polarization states suitable for nuclear physics experiments.

Abstract

A polarized atomic beam source was developed for the polarized internal storage-cell gas target at the magnet spectrometer ANKE of COSY-J\"ulich. The intensities of the beams injected into the storage cell, measured with a compression tube, are $7.5\cdot 10^{16}$ hydrogen atoms/s (two hyperfine states) and $3.9\cdot 10^{16}$ deuterium atoms/s (three hyperfine states). For the hydrogen beam the achieved vector polarizations are $p_{\rm z}\approx\pm0.92$. For the deuterium beam, the obtained combinations of vector and tensor ($p_{\rm zz}$) polarizations are $p_{\rm z}\approx\pm 0.90$ (with a constant $p_{\rm zz}\approx +0.86$), and $p_{\rm zz}=+0.90$ or $p_{\rm zz}=-1.71$ (both with vanishing $p_{\rm z}$). The paper includes a detailed technical description of the apparatus and of the investigations performed during the development.