Relativistic heavy ions are copious sources of virtual photons. The large photon flux gives rise to a substantial photonuclear interaction probability at impact parameters where no hadronic interactions can occur. Multiple photonuclear interactions in a single collision are possible. In this Letter, we use mutual Coulomb excitation of both nuclei as a tag for moderate-impact-parameter collision...

We report the measurement of the spin polarization of hydrogen (SPH) atoms by (2+1) laser-induced fluorescence, produced via the photodissociation of thermal HBr molecules with circularly polarized 193 nm light. This scheme, which involves two-photon laser excitation at 205 nm and fluorescence at 656 nm, offers an experimentally simpler polarization-detection method than the previously reported...

The two-photon production by motion of a charged particle in a medium is considered. This process is called Čerenkov-Compton effect (ČCE) because the production of photons is calculated from the Feynman diagram for the Compton effect in a medium. This process is not forbidden in quantum electrodynamics of dielectric media.The cross section of this process in Mandelstam variables is calculated f...

Argon 3-M23M23 Auger-electron spectra were measured in coincidence with Ka fluorescent x-rays in studies of Ar K-shell vacancy decays a t several photon energies above t h e K-threshold and on the 1 s 4p resonance in atomic argon. The complex spectra recorded by conventional electron spectroscopy are greatly simplified when recorded in coincidence with fluorescent x-rays, allowing a more detail...

The two-photon collision option of the International Linear ee Collider (ILC), a photon linear collider (PLC), is using back-scattered laser photons off the incident electrons and/or positrons. 1,2 A photon collider provides unique capabilities for probing new physics appearing in neutral spin-zero particles such as neutral Higgs bosons in the Standard Model (SM) and its Minimal Supersymmetric ...

We aim to search for axion-like particles in the eV mass range using a variable-angle stimulated resonance photon collider (SRPC) with three intense laser beams. By changing angle of incidence beams, center-of-mass-system collision energy can be varied and continuously searched for. In this paper, we present design construction such three-beam SRPC (tSRPC), verification mechanism calibration la...

Bremsstrahlung is one of the basic photon-matter processes occurring in collisions of electrons with atoms and ions. Bremsstrahlung in electron-atom collisions has been the object of extensive experimental and theoretical studies [1]. These studies focused on the angular dependence of the intensity distribution of the bremsstrahlung, as well as on its linear polarization [2]. Another production...

For the next generation of linear colliders, the energy loss due to beamstruhlung during the collision of the e+ebeams is expected to substantially influence the effective center-of-mass energy distribution of the colliding particles. In this paper, we first derive analytical formulae for the electron and photon energy spectra under multiple beamstrahlung processes, and for the e+eand +yr diffe...

We present results of a search in 929 ± 56 pb −1 of p¯ p collisions at 1.96 TeV for the anomalous production of events containing a charged lepton (ℓ, either e or µ) and a photon (γ), both with high transverse momentum, accompanied by additional signatures, X, including missing transverse energy (E T) and additional leptons and photons. We use the same selection criteria as in the previous CDF ...

We investigate the atom-optical analog of degenerate four-wave mixing by colliding two Bose-Einstein condensates of metastable helium. The momentum distribution of the scattered atoms is measured in three dimensions. A simple analogy with photon phase matching conditions suggests a spherical final distribution. We find, however, that it is an ellipsoid with radii smaller than the initial collis...