Calculation of proton polarization in deuteron disintegration with longitudinally polarized electrons

For the reaction dependences of the proton polarization on the deuteron electromagnetic current and on the final-state interaction are studied. The possibility of separation of the structure functions contributing to this observable is discussed. Polarizations of protons in are calculated for the kinematics of a proposed measurement in the MIT-Bates research program.     

Emission of circularly polarized recombination radiation from p-doped GaAsP bombarded with longitudinally polarized electrons

We report measurements of circularly polarized recombination radiation from a GaAs_0.6P_0.4 crystal bombarded with longitudinally spin polarized electrons of 10 eV energy. Qualitatively, this process can be considered as the inverse of the photoemission utilized in GaAs and GaAsP polarized-electron sources. The measured degree of circular polarization is 0.29%±0.06% if the crystal is cooled with liquid nitrogen and the incident electrons are 15%±3% polarized.     

Resonant neutral-particle emission in collisions of electrons with peptide ions in a storage ring

Electron-biomolecular ion collisions were studied using an electrostatic storage ring with a merging beam technique for singly protonated peptides (angiotensin I, II, and III). A strong neutral-particle emission at around 6.5 eV was found in addition to neutrals from recombination at low energies. The rates of the high-energy peak greatly decreased with a slight decrease in the number of amino-acid residues from angiotensin I to III. These results suggest that some peptide bonds were selectively cleaved.     

Effects of the finite size of a nucleus having a magnetic dipole moment on the bremsstrahlung of longitudinally polarized electrons

Expressions are obtained in the Born approximation for the differential cross section and circular polarization of the bremsstrahlung radiated by longitudinally polarized electrons in the field of a nucleus having a magnetic dipole moment. Account is taken of the rms radius and the fourth moment of the charge distribution and the magnetic moment of the nucleus. The effects of r² and r⁴ on the spectrum of the charge and magnetic bremsstrahlung are studied.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 97–104, September, 1969.The authors thank professor A.A. Sokolov for discussion of these results.     

Experiments with internal targets at the VEPP-3 electron storage ring

An overview of the recently completed, current, and planned experiments with internal targets at the VEPP-3 electron-positron storage ring in Novosibirsk is given. The results of the experiment to separately measure the deuteron form factors in elastic ed scattering in the range of momentum transfer Q ² = 8?15 fm^?2 are provided. The results of measuring the tensor analyzing power components of the tensor-polarized deuteron photodisintegration reaction in the range of γ-quantum energies E _γ = 25?600 MeV are presented. The tensor analyzing powers of the coherent photoproduction of a neutral pion on a tensor-polarized deuteron have been measured for the first time. The almost-real photon tagging system being created is discussed. The status of the experiment under way to determine the contribution of two-photon exchange to the elastic ep scattering cross section is described.     

Measure h/e2 by counting electrons or ions in a storage ring

Storage rings offer the possibility of realizing a current by counting the electrons or ions per second passing through a toroidal SQUID current comparator. This technique offers the possibility of accurately measuring the quantity h/e² and providing a stringent test of the quantum Hall effect.     

Generation of sub-wavelength and super-resolution longitudinally polarized non-diffraction beam using lens axicon

It is well known that a light spot of sub-wavelength will diverge in all directions. In this letter, A method is presented for generating sub-wavelength (0.44λ) longitudinally polarized beam, which propagates without divergence over lengths of about 2λ in free space. This is achieved by a high numerical aperture (NA) lens axicon that utilizes spherical aberration to duplicate the performance of an axicon and to create an extended focal line.     

Current tensor with a heavy photon for pair production by a longitudinally polarized electron

The electron current tensor for the scattering of a heavy photon on a longitudinally polarized electron accompanied with an additional electron-positron pair is considered. The contribution of soft and hard collinear and quasi-collinear pairs is taken into account. The full analysis of the spin-independent and spin-dependent parts of the electron current tensor is performed. The results allow us to calculate the corresponding contribution into the second-order radiative correction to cross sections for different processes with the next-to-leading accuracy.     

Testing weak neutral currents in longitudinally polarized colliding beams

We study the effects of a weak neutral current as they show up in longitudinally polarized colliding beams. The reactions considered here are e⁺e^?→μ⁺μ^? and e⁺e^?→π⁺π^?. The electromagnetic background and means to suppress this are also discussed.     

Electron exchange in dissociative excitation of molecular hydrogen using polarized electrons

The effects of electron exchange and spin orbit interaction in dissociative excitation processes in H2 molecules have been explored using excitation by polarized electrons. Observations of the circular and linear Stokes polarizations of the Balmer-alpha photons determined the alignment and orientation of the excited atomic hydrogen atoms, the excited molecular states, and the dissociative excitation processes via predissociation with short and long range transitions.     

Test of cosmic spatial isotropy for polarized electrons using a rotatable torsion balance

To test the cosmic spatial isotropy, we use a rotatable torsion balance carrying a transversely spin-polarized ferrimagnetic Dy6Fe23 mass. With a rotation period of 1 h, the period of anisotropy signal is reduced from one sidereal day by about 24 times, and hence the 1/f noise is reduced. Our present experimental results constrain the cosmic anisotropy Hamiltonian H=C(1)sigma(1)+C2sigma(2)+C3sigma(3) (sigma(3) is in the axis of earth rotation) to (C(2)(1)+C(2)(2))(1/2)=(1.1+/-2.0)x10(-20) eV and /C(3)/=(1.1+/-6.0)x10(-19) eV. This improves the previous limits on (C(2)(1)+C(2)(2))(1/2) by 27 times.     

Synchrotron radiation from a longitudinally polarized relativistic spinning particle in pseudoclassical theory

The spin dependence of the intensity and polarization of synchrotron radiation from a longitudinally polarized particle moving at a constant speed along a circle in a uniform magnetic field is investigated within the pseudoclassical approach.     

Acceleration of polarized electrons in a weakly focusing synchrotron

The design of a system to obtain polarized electrons and photons in the Tomsk synchrotron is considered. The spin motion in injectors-linear accelerators and microtrons is investigated. Results of the change in polarization during acceleration in the synchrotron are presented.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 23–28, June, 1977.     

Compton tensor with heavy photon for longitudinally polarized electron with next-to-leading accuracy

Compton tensor for scattering of a longitudinally polarized electron by a heavy photon is considered. The result obtained can be used for the analysis of electromagnetic corrections to the spin-spin correlation in quasi-elastic and deep inelastic scattering with next-to-leading accuracy.     

Formation and interaction of low-energy electrons and biomolecular ions in electrostatic storage ring

The interaction between delta electrons and DNA molecules and other biological structures is one of the important processes taking place in hadron therapy. This paper discusses the formation of low-energy electrons and ions of DNA molecules and other biomolecular ions in an electrostatic storage ring. The results of experimental studies into the interaction between electrons and biomolecular ions for a simulation of the contribution that delta electrons make to the radiation damage of cells in hadron therapy are presented.