7#Jc F    P@x *112PHYSICS 310 Production Properties of X-Rays References: Enge, Wehr, Richards, Introduction to Atomic Physics, Chapter 10 Tipler, Modern Physics, Chapters 4-4 and beginning of 8-4 This experiment introduces you to an extremely rich area of modern physics by investigating several aspects of production, scattering, and absorption of x-rays, including discussions of the quantized nature of the phenomena. The basic tool is the Tel-Tron X-Ray Spectrometer which is unfortunately showing some signs of wear. All the exercises are detailed in the accompanying pamphlet, "Student Enquiry Series D - The Production Properties and Uses of X Rays". Also read the comments below - if nothing else to save yourself unnecessary work. The required work in this experiment: i) Carefully read the introductory material of Part I. It is not necessary to perform all the Operational Alignment and Experimental Verification procedures as described in Sections 12 and 13; for example it is better not to loosen the screws and grommets holding down the lead-glass dome, because they are connected to safety switches that are wearing. However, alignment is important for getting maximal performance from the apparatus. Thus you should check visually that all slits and the crystal face are aligned when the detector arm is at zero degrees. The point of checking the count rate for LiF at 45o is to verify angular symmetry and to establish the width of your X-ray lines. Warning: Changing sides in this spectrometer involves rotating the central turntable by 1800. You HAVE to take out the crystal and remove its small clamp in order to be able to loosen the central clamp of the turntable. Do not force the turntable! You are in danger of ruining the 1 to 2 ratio between crystal angle and detector angle if you force this. ii) D14 (Bragg Scattering): The counter is more appropriate than the ratemeter, although the audio signal is useful to first get a "feel" for the phenomenon. Using 30 kV and a NaCl crystal take the entire spectrum on one side of the midline and measure only the peak positions - carefully - on the other side. Check which crystal face and which side of the spectrometer yields better count rates before starting on a lengthy measurement. For 20 kV, investigating the peak regions is sufficient. iii) D16 (X-Ray Absorption by Varied Targets): Three targets are sufficient - for example Cu, Zn, and Co. Read counts at 0.5 degree intervals. To improve the support of the auxiliary slide holder consider using the small pieces of cork in our toolbox. iv) D17 (X-Ray Scattering): The rotator does not always properly align the scattering surface - be careful! It may be better to choose a scattering foil and take Io and the intensities for the four absorber foils, then change scatterer. Plot I/Io as a function of atomic number, not atomic weight. As usual, any measured quantity needs to be quoted with an error, i.e. uncertainty. This is particularly true for the wavelengths of th Ka and Kb lines of Copper determined in D14. In addition to the usual tables and plots, you are expected to cite the conclusions based on the data, and the significance of each conclusion. Much of the theory is provided in the pamphlet or in introductory texts on modern physics. Revised August 1998 (EC) Richard S. Galik 20-Feb-90 Edith Cassel August 1998 x{|v%`White Pine Telnet%`~FTPY%`~FTPY%`SOMobjects for Mac OS%`SOMobjects for Mac OS%`SOMobjects for Mac OS%`SOMobjects for Mac OS%`QuickTime Musical InstrumentsY%`QuickTime Musical InstrumentsY^4 b8-st!(   FGIJV @     -{ )  ! Q #-:FGHIJú %!% P%h%h%h%h%h %h%h%h%h% n-Times 12 Point,Flush left3  JJ  JVJ   ((()9? HH(FG(HH(d`@=/88R`dH-:LaserWriter 8 TimesSymbol  (c(2Department of PhysicsDepartment of Physics