Abstract: A method for cluster fragmentation comprises the production of at least one cluster which contains a carrier substance and the fragmentation of the cluster into cluster fragments, with the cluster being loaded before the fragmentation with at least one reaction partner and the reaction partner being part of at least one cluster fragment after the fragmentation. A cluster beam system for performing the method, and applications of the cluster fragmentation for analysis and purification of surfaces, for analysis of clusters, and for the operation of ion thrusters are also described.

Abstract: A mass spectrographic method and apparatus provide simultaneous quantification of multiple target species of gaseous neutral particles that may be laser sputtered from a sample. The invention employs non-resonant multiphoton ionization of the target species with a high intensity laser beam propagated toward a given extraction volume from which volume ions are withdrawn for quantification. In preferred embodiments, the given volume is defined by an acceptance aperture and a transverse energy acceptance interval which is itself defined by energy discrimination of the ions into bunches with a novel ion mirror. An inventive embodiment of ion mirror has four grids at different spacings and potentials with a second grid away from the acceptance aperture having a potential just below a third to separate out an undesired, low-energy ion bunch. Curves for simultaneously quantifying Ta.sup.+ ions with Ta.sup.++ ions are shown.

Abstract: A method and an apparatus for non-resonant photoionization of multiple species of neutral particles of a gas in which the neutral particles are ionized in an ionization space by a laser beam having a maximum intensity above the saturation intensity for ionizing neutral particles of multiple desired types. The ions so produced are extracted from the ionization space by an ion-optical system. The ionization of the desired types of neutral particles and/or the extraction of the produced ions are confined by light-optical or ion-optical means to a sharply limited space in which the intensity of the laser beam is above the saturation intensity or is negligibly low with respect to the ionization of neutral particles of interest, so that the number of extracted ions of the ion type of interest does not substantially increase when the laser beam intensity is further increased. The multiple ionized species can be quantitatively determined mass spectrographically in a single step.

Abstract: In the transmission of a color television signal containing chrominance burst and sync signals over a Nyquist channel between a transmitting station and a receiving station, a method for modulating and synchronously demodulating the television signal according to the offset modulation and offset sampling principle. The chrominance burst or sync pulses are used as a reference signal for frequency recovery at the receiving station. An additional reference signal is generated at the transmitting station and transmitted over the Nyquist channel. The additional reference signal is utilized for phase recovery at the receiving station.