A novel periodic magnetic field ͑PMF͒ optic is shown to act as a prism, lens, and polarizer for neutrons and particles with a magnetic dipole moment. The PMF has a two-dimensional field in the axial direction of neutron propagation. The PMF alternating magnetic field polarity provides strong gradients that cause separation of neutrons by wavelength axially and by spin state transversely. The spin-up neutrons exit the PMF with their magnetic spins aligned parallel to the PMF magnetic field, and are deflected upward and line focus at a fixed vertical height, proportional to the PMF period, at a downstream focal distance that increases with neutron energy. The PMF has no attenuation by absorption or scatter, as with material prisms or crystal monochromators. Embodiments of the PMF include neutron spectrometer or monochromator, and applications include neutron small angle scattering, crystallography, residual stress analysis, cross section measurements, and reflectometry. Presented are theory, experimental results, computer simulation, applications of the PMF, and comparison of its performance to Stern-Gerlach gradient devices and compound material and magnetic refractive prisms.

Many materials and electronics need to be tested for the radiation environment expected at linear colliders (LC) since both accelerator and detectors will be subjected to large fluences of hadrons, leptons and γ's over the life of the facility [1]. While the linacs will be superconducting, there are still many uses for NdFeB in the damping rings, injection and extraction lines and final focus. Our understanding of the situation for rare earth, permanent magnet materials was presented at PAC03 [2]. Our first measurements of fast neutron, stepped doses at the UC Davis McClellan Nuclear Reactor Center (UCD MNRC) were presented at EPAC04 [3]. We have extended the doses, included other manufacturer's samples, and measured induced radioactivities which are discussed in detail.

Many materials and electronics need to be tested for the radiation environment expected at linear colliders (LC) where the accelerator and detectors will be subjected to large fluences of hadrons, leptons and γ's over their life[1]. Examples are NdFeB magnets considered for the damping rings and final focus, electronic and electro-optical devices to be utilized in detector readout and accelerator controls and CCDs required for the vertex detector. Effects of γ's on many materials have been presented[2] and our understanding of the situation for rare earth permanent magnets at PAC2003[3]. Here we give first measurements of the fast neutron, stepped doses at the UC Davis McClellan Nuclear Reactor Center (UCD MNRC) together with the induced radioactivities. Damage appears to be proportional to the distances between the operating point and H ci .

No abstract

The outcoming flow rate 37 7. GENERAL EQUATIONS(CONCEPT OF TRANSFER MATRIX) 38 iv 7.1 The Transfer Matrix 38 7.1.1 Definition of the transfer matrix 39 7.1.2 Construction of the transfer matrix 40 7.2 Use of the Transfer Matrix in the Nodal Model 41 7.3 Benchmark Problem 41 7.3.1 The incoming flow rate (IFW) 43 7.3.2 The outcoming flow rate (OFW) 44 8. THE OVERALL TRANSFER MATRIX 48