A dilution cryostat for experiments with the polarized target

Polarized targets can be used in experiments with photo production reactions to study a baryon resonance spectrum. The principle of operation of the frozen spin polarized target is based on a long nuclear spin relaxation time at low temperatures (approximately 50 mK) and moderate magnetic fields (mo...

Full description

Saved in:
Bibliographic Details
Main Authors: Dolzhikov, Anton, Gorodnov, Ivan, Borisov, Nicolai, Usov, Yury
Format: Conference Proceeding
Language:English
Subjects:
Accelerators
Baryon resonance
Cryostats
Dilution
Experiments
Magnetic fields
Nuclear spin
Polarization
Refrigerators
Relaxation time
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Polarized targets can be used in experiments with photo production reactions to study a baryon resonance spectrum. The principle of operation of the frozen spin polarized target is based on a long nuclear spin relaxation time at low temperatures (approximately 50 mK) and moderate magnetic fields (more than 0.3 T). After a polarization build-up with the Dynamic Nuclear Polarization process, microwave power is turned off and polarization is “frozen in”. Then a magnetic field is lowered till about 0.3 T, so the spin relaxation time can be many days at about 50 mK. To achieve such low temperatures dilution cryostats are used. In this article a description of the design, construction and recent results of the horizontal cryostat for the new Bonn frozen spin target, which is being developed for spin physics experiments with tagged photons from the Bonn electron accelerator “ELSA”, are given. In addition, an overview of the frozen spin polarized targets cooled by 3He/4He dilution refrigerators developed at DLNP JINR since 1976 for different accelerators is given.
ISSN:0094-243X
1551-7616
DOI:10.1063/1.5130118