相关论文: On semi-exclusive measurement of $\gamma\gamma\to\…
Plasma scattering measurement is effective technique to observe low frequency density fluctuations excited in plasma. The spatial and wave number resolutions and the S/N ratio of measurement depend on the wavelength range, the size and the…
The diffractive scattering of photon off proton $\gamma^{(*)} p \to \gamma Y$ (where $Y$ denotes the proton dissociative system or the elastically scattered proton) is measured in two different kinematic regimes at high energy with the H1…
The presence of $2\gamma$-exchange in electron proton elastic scattering is discussed. From C-invariance and crossing symmetry, $2\gamma$ contribution induces a specific dependence of the reduced cross section on the variable $\epsilon$. No…
Exclusive photoproduction of a $\gamma\,\rho$ pair in the kinematics where the pair has a large invariant mass and the final nucleon has a small transverse momentum is described in the collinear factorization framework. The scattering…
The first measurements of the beam-target-helicity-asymmetries $E$ and $G$ in the photoproduction of $\omega$-mesons off protons at the CBELSA/TAPS experiment are reported. $E$ ($G$) was measured using circularly (linearly) polarised…
Photons preferentially Compton scatter perpendicular to the plane of polarisation. This property can be exploited to design instruments to measure the linear polarisation of hard X-rays ($\sim$10 - 100 keV). Photons may undergo two…
Differential cross sections for $\gamma p \to K^+\Lambda(1405)$ and $\gamma p \to K^+\Sigma^0(1385)$ reactions have been measured in the photon energy range from 1.5 to 2.4 GeV and the angular range of $0.8<\cos(\Theta)<1.0$ for the $K^+$…
We discuss the exclusive photoproduction of a photon-meson pair with large $ p_{T} $ as a channel to probe generalised parton distributions (GPDs). Like other $ 2\to3 $ exclusive processes, this channel allows us to better study the $ x…
Observing the production of the Higgs particle in the $\gamma$-$\gamma$ mode of a linear $e^+e^-$ collider allows for the measurement of the $H\gamma\gamma$ coupling. We point out that for the intermediate Higgs mass range this measurement…
The process of exclusive vector meson production (gamma gamma to J/psi rho^0) is studied for almost real photons. This process may be reduced to photoproduction of J/psi off the rho^0 meson. We discuss the possibility of extracting the…
Exclusive rho+rho- production in two-photon collisions between a quasi-real photon, gamma, and a mid-virtuality photon, gamma*, is studied with data collected at LEP at centre-of-mass energies root(s)=183-209GeV with a total integrated…
The production of isolated photons in deep-inelastic scattering $ep\to e \gamma X$ is measured with the H1 detector at HERA. The measurement is performed in the kinematic range of negative four-momentum transfer squared $4<Q^2<150 $~GeV$^2$…
Semi-exclusive processes like \gamma p \to \pi^+ Y are closely analogous to DIS, ep \to eX, in the limit where the momentum transfer |t| to the pion and the mass of the inclusive system Y are large but still much smaller than the total CM…
We present the recent measurements of exclusive processes performed in the CMS experiment at the LHC using data collected at a centre of mass energy of 7 TeV. These measurements include the double-pomeron production of photon pairs, the…
Compton scattering by the proton has been measured over a wide range covering photon energies 250 MeV < E_\gamma < 800 MeV and photon scattering angles 30^0 < \theta^{lab}_\gamma < 150^0, using the tagged-photon facility at MAMI (Mainz) and…
Differential cross sections for Compton scattering from the proton have been measured at scattering angles of $55^\circ$, $90^\circ$, and $125^\circ$ in the laboratory frame using quasimonoenergetic linearly (circularly) polarized photon…
We present a theoretical investigation of the resonant elastic scattering of laser photons by ultra-relativistic partially stripped ions, that is the core process of the Gamma Factory project. Special emphasis in our study is placed on the…
Two-photon emission of an electron in an electromagnetic plane wave of vanishing frequency is calculated. The unpolarised probability is split into a two-step process, which is shown to be exactly equal to an integration over polarised…
We define and study hard ``semi-exclusive'' processes of the form $A+B \to C + Y$ which are characterized by a large momentum transfer between the particles $A$ and $C$ and a large rapidity gap between the final state particle $C$ and the…
The exclusive production of proton-antiproton pairs in the collisions of two quasi-real photons had been studied using data taken at sqrt(s)_ee=183 GeV and 189 GeV with the OPAL detector at LEP. Results are presented for Ppbar invariant…