Energieverlust und Reichweite von α-Teilchen in Bor im Energiebereich von 0,2 bis 5,3 MeV

With a scintillation spectrometer the air equivalent of boron for α-particles has been measured as a function of the energy. The boron foils (50?120 μg·cm^?2) were evaporated onto thin mica. The α-particle energy was set to between 0.2 and 5.3 MeV by letting the particles of a²¹⁰Po-α-source pass through air. With known data for the energy loss in air the range and stopping power in boron have been determined. The error of each measured datum is about 2%.     

Die Szintillationslichtausbeute energiereicher Deuteronen und α-Teilchen in organischen Kristallen

The light output of anthracene and terphenyl bombarded with deuterons from 8 to 25.3 MeV and with α-particles from 20 to 49.5 MeV has been measured as a function of energy. Both anthracene and terphenyl gave for low energies a nonlinear response tending towards linearity above 18 MeV for deuterons and 35 MeV for α-particles. The dependence of the light output upon the impact direction of the incident particles has been found not to be disappearing even at highest energies, but in contrast there appear new fine structures. Furtheron the specific light outputdS/dxvs specific energy lossdE/dx has been investigated in direct measurements on thin crystals. The quantitydS/dx depends on the impact direction even atdE/dx=35 keV/mg cm^?2.     

Über spektroskopische Untersuchungen mit Hilfe von α-Teilchen

Excitation of the molecules of various gaseous substances byα-particles from a polonium 210 source has been investigated, expecially with respect to the branching between dissociation andγ-de-exitation. The use of an alternative irradiation source is briefly discussed.     

Über die Photoleitung von Anthrazen

The dependence of the photocurrent on voltage, light intensity and electrode separation and also the decay-time of the photocurrent is measured. All these measurements are largely influenced by the electrode material. The results obtained with Cu I- and Al-electrodes and also with insulating electrodes are given and the different behavior is discussed by means of a model. Hereby conclusions are made about the mean ranges and the mobility of the holes which are mainly responsible for the photocurrent.     

Die dickenabhängige Drehung der Lichtausbeutecharakteristik von Anthrazen- und p-Terphenylkristallen beim Beschuß mit α-Teilchen

Zeitschrift für Physik A Hadrons and nuclei - Thick single crystals of anthracene and para-terphenyl have a maximum of their scintillation yield with the impact direction of the...