Spin fluctuation and transition have always been one of the central topics of magnetism and condensed matter science. Experimentally, the spin fluctuation is found transcribed onto scattering intensity in the neutron-scattering process, which is represented by dynamical magnetic susceptibility and maximized at phase transitions. Importantly, a neutron carries spin without electric charge, and t...

The smallness of natural molecules and atoms with respect to the wavelength of light imposes severe limits on the nature of their optical response. For example, the well-known argument of Landau and Lifshitz and its recent extensions that include chiral molecules show that the electric dipole response dominates over the magneto-electric (bianisotropic) and an even smaller magnetic dipole optica...

We present rigorous quantum calculations for low-temperature collisions of OH((2)Pi) molecules with He atoms in the presence of external electric and magnetic fields. We show that electric fields of less than 15 kV/cm can be used to enhance the probability for Stark relaxation in collisions of OH (F(1), J = 3/2, M = 3/2, f) molecules by 3 orders of magnitude. The inelastic cross sections displa...

In this paper, we have simulated the excitation of wake fields in the interaction of an intensive laser pulses having Half-Sine and Gaussian time envelopes with a fully ionized cold plasma using particle in cell (PIC) method. We investigated the dependency of wake filed amplitude to different laser and plasma parameters such as laser wavelength, pulse duration and electron number density. In ad...

A previous study proposed an optimal vibration isolator for self-excitation, but the solution results showed a critical drawback basement input. Because plant system is exposed to self-excitation and input, characteristics must meet all requirements of both excitation cases. Two performance indices were introduced evaluate control capability over two cases, using theoretical linear model electr...

Two methods to scale plane-wave Born cross sections for electron-impact excitations of neutral atoms are shown to produce excitation cross sections comparable in accuracy to those obtained by more sophisticated collision theories such as the convergent close-coupling method. These scaling methods are applicable to integrated cross sections for electric dipole-allowed transitions. Scaled cross s...

The electromagnetic excitation of the two-phonon isovector giant dipole resonance in relativistic projectiles incident on heavy targets can be proceed via several intermediate 1 − one-phonon giant resonance states. In two step electric dipole transitions the population of 0 + , 1 + , and 2 + two-phonon states are possible. We calculate the amplitude distribution of 1 − excitations with an RPA f...

Generalized nucleon polarizabilities for virtual photons can be defined in terms of electroproduction cross sections as function of the 4-momentum transfer Q 2. In particular, the sum of the generalized electric and magnetic polarizabilities Σ = α + β and the spin polarizability γ can be expressed by virtual photon absorption cross sections integrated over the excitation energy. These quantitie...

Generalized nucleon polarizabilities for virtual photons can be deened in terms of electroproduction cross sections as function of the 4-momentum transfer Q 2. In particular, the sum of the generalized electric and magnetic polarizabilities = + and the spin polarizability can be expressed by virtual photon absorption cross sections integrated over the excitation energy. These quantities have be...