PN1 - Fission-product spectrometer
PN1 (Lohengrin) - an exotic-isotope spectrometer
LOHENGRIN is a recoil mass spectrometer for studying the properties of the exotic isotopes produced during the fission process. It allows us to study the mass, kinetic energy and charge distribution of the products of thermal-neutron-induced nuclear fission at very high resolution.
The beam intensity at the separator also makes it possible to detect γ-rays, conversion electrons, β-rays and delayed neutrons, and coincidences between these particles.
Applications
the investigation of spectroscopic properties of exotic neutron-rich nuclei:
- spins and parities
- magnetic moment and life-time measurements of excited nuclear states
- conversion electron spectroscopy
fission process investigation and industrial applications:
- fission fragments' mass, kinetic energy and nuclear charge distributions for different fissile systems from binary and ternary fission reactions
- delayed neutrons from fission fragments
- diffusion coefficients for actinids in different surrounding material.
Instrument layout
The instrument combines horizontal magnetic deflection with subsequent vertical electrostatic deflection. The focusing magnet, the Reverse Energy Dispersion (RED) dipole magnet, increases the particle density at the focal position by up to a factor of seven.
Example of detector setup
Each experiment uses its own set of ionization chambers, surface barrier detectors, Si and Ge detectors, plastic scintillators, etc., which are mounted on top of the focussing device, the Reverse Energy Dispersion (RED) dipole magnet.