A new drift chamber concept with a special charge-sampling geometry, pulse shaping electronics and a 100 MHz flash ADC readout was for the first time operated in a colliding e+ e− beam environment. The detector formed part of the MARK J experiment at PETRA (DESY) during the last year before its final shutdown in November 1986. Operated with a CO2/i-C4H10 gas mixture at 1.9 bar, an intrinsic resolution of 40 μm for Bhabha events has been achieved.

A high-resolution drift chamber based on the time expansion principle has been built as a vertex detector for the Mark J experiment at DESY. The chamber design and the associated control and readout system are described. Results on chamber performance obtained from test beam measurements and first results from running at PETRA are reported.

The design and results from a beam test for a small vertex detector, now installed in the DESY MARK J experiment, are presented. The concept of this drift chamber is based on the time expansion principle with readout planes inclined to solve the left-right ambiguity. A spatial resolution of 35 μm, varying weakly as a function of drift length and azimuthal angle, has been achieved.

The Optical Fiducial Volume Trigger system (OFVT) has been developed for use with the Rapid Cycling Bubble Chamber (RCBC), serving as a vertex detector in the European Hybrid Spectrometer (EHS). Its purpose is to decide whether an interaction took place within the useful (fiducial) volume of the chamber. In this way it complements the main interaction trigger which lacks the necessary accuracy of vertex localisation. The system can reduce the cost of film material, film treatment and scanning by up to 60%, the precise saving being dependent on the experimental conditions. The principle of the optical track detection by linear diode arrays is described, as well as details of the hardware construction. The properties of the system are discussed on the basis of results from the first run with RCBC.

A description is given of the software algorithms used for the Optical Fiducial Volume Trigger system (OFVT) and the implementation on-line. The OFVT system has the purpose of enhancing the efficiency of the trigger system for the Rapid Cycling Bubble Chamber (RCBC) of the European Hybrid Spectrometer (EHS). One obtains an efficiency for good events of 80–90% and a rejection efficiency for events outside the bubble chamber fiducial volume of 60–70%. With the use of OFVT the fraction of pictures containing a useful event rises from 30% to 55%.

This paper describes an instrument and test method to continuoslly measure the non-deflected spot position of a CRT over a long time with a precision of about 1 μm.

Fette, Seifen, AnstrichmittelVolume 69, Issue 7 p. 538-539 Article Transparentes flüssiges Shampoo H. Anders, H. Anders ReutlingenSearch for more papers by this author H. Anders, H. Anders ReutlingenSearch for more papers by this author First published: 1967 https://doi.org/10.1002/lipi.19670690709AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume69, Issue71967Pages 538-539 RelatedInformation

This paper deals with the reflective properties of inhomogeneous thin films that in addition may or may not be absorbing. Reflection coefficients have been computed using two different techniques and are plotted as functions of wavelengths. The practical uses of nonabsorbing inhomogeneous thin films include antireflection coatings for broad spectral ranges; absorbing inhomogeneous thin films are useful for making black coatings, rulings, field stops, and sunglasses.

The scanner described follows the principles of the Hough-Powell digitizer, but a cathode ray tube is used as flying spot generator. Direction of scan can be 0 un. Concent 85% or 90 un. Concent 85% , number of lines can be 100 to 800, and scan time per line is 750 sec. Digitizing along the scan lines is done by starting an oscillator at the well-defined edge of the picture and counting its oscillations. In the perpendicular direction, the number of the scan lines will be used. The device will be calibrated at regular intervals by scanring a test pattern. Stability has been found to be better than 0.1% over periods of 30 sec. (A.G.W.)

Bei dem hier beschriebenen Sender für den Wellenlängenbereich von 3 bis 1 cm befindet sich einHertzscher Oszillator in einem fast vollständig geschlossenen Hohlraumresonator. Da der Oszillator im Hohlraum gleichzeitig mehrere Eigenwellen anregt, wird die Strahlung durch einen zweiten Resonator geschickt, dessen Spektrum nur in einer Eigenwelle mit dem des ersteren übereinstimmt. Auf diese Weise erhält man eine nahezu monochromatische Strahlung mit log. Dekrementen von der Größe 0,01. Die Intensität reicht für Meßzwecke aus.