相关论文: Optimal Axes of Siberian Snakes for Polarized Prot…

Solenoid Siberian snakes have successfully maintained polarization in particle rings below 1 GeV, but never in multi-GeV rings because the Lorentz contraction of a solenoid's integral B dl would require impractically long high-field…

Here, and in a sequel, we invoke the invariant spin field to provide an in--depth study of spin motion at and near low order orbital resonances in a simple model for the effects of vertical betatron motion in a storage ring with Siberian…

A "Figure 8" shaped synchrotron is suggested for use in accelerating polarized protons in the energy range below ~ 20 GeV. The spin tune in such an accelerator does not ramp with energy and is equal to zero . Then the intrinsic spin…

Frequent polarization reversals, or spin-flips, of a stored polarized beam in a high energy scattering asymmetry experiments may greatly reduce systematic errors of spin asymmetry measurements. A spin-flipping technique is being developed…

Polarized proton beams at HERA can currently only be produced by extracting a beam from a polarized source and then accelerating it in the three synchrotrons at DESY. In this paper, the processes which can depolarize a proton beam in…

This paper reports the first spin tune measurement at high energies (24 GeV and 255 GeV) with a driven coherent spin motion. To maintain polarization in a polarized proton collider, it is important to know the spin tune of the polarized…

The successful operation of the future Electron-Ion Collider is contingent on maintaining high hadron beam polarization up to 275 GeV. The Hadron Storage Ring lattice, however, features a symmetry-breaking interaction region that excites…

When polarized particles are accelerated in a synchrotron, the spin precession can be periodically driven by Fourier components of the electromagnetic fields through which the particles travel. This leads to resonant perturbations when the…

The orbital polarization of twisted electrons carrying an intrinsic orbital angular momentum is not influenced by field perturbations in arbitrary magnetic fields. This property means an existence of the Siberian snake-like behavior for an…

The Main Injector (MI) at Fermilab currently produces high-intensity beams of protons at energies of 120 GeV for a variety of physics experiments. Acceleration of polarized protons in the MI would provide opportunities for a rich spin…

Spin-polarized beams are important for some nuclear and high-energy physics experiments, such as those planned for the future Electron-Ion Collider (EIC). However, maintaining polarization during the acceleration of a charged-particle beam…

Polarized protons have never been accelerated to more than about $25$GeV. To achieve polarized proton beams in RHIC (250GeV), HERA (820GeV), and the TEVATRON (900GeV), ideas and techniques new to accelerator physics are needed. In this…

We determine analytically the form of optimal snake locomotion when the coefficient of transverse friction is large, the typical regime for biological and robotic snakes. We find that the optimal snake motion is a retrograde traveling wave,…

We develop a numerical scheme to determine which planar snake motions are optimal for locomotory efficiency, across a wide range of frictional parameter space. For a large coefficient of transverse friction, we find that retrograde…

This is an addendum to the paper "Some models of spin coherence and decoherence in storage rings" by one of the authors [1] in which spin diffusion in simple electron storage rings is studied. In particular, we illustrate in a compact way,…

Snake ``resonances'' are classified in terms of the invariant spin field and the amplitude dependent spin tune. Exactly at snake ``resonance'' there is no continuous invariant spin field at most orbital amplitudes.

I examine various ideas for radiative polarization at TLEP/FCC-ee and formulate some estimates for the polarization buildup time and the asymptotic polarization. Using wigglers, a useful degree of polarization (for energy calibration), with…

We optimize three-dimensional snake kinematics for locomotor efficiency. We assume a general space-curve representation of the snake backbone with small-to-moderate lifting off the ground and negligible body inertia. The cost of locomotion…

Orbital periods in AM Her stars (polars) are synchronized with spin periods of white dwarf by its high magnetic field. Since the last study of Porb distribution of these systems, the number of known objects of such type has more than…

The choice of a figure 8 shape for the booster and collider rings of MEIC opens wide possibilities for preservation of the ion polarization during beam acceleration as well as for control of the polarization at the collider's interaction…