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Type of Document	Dissertation
Author	Vette, James I.
URN	etd-04112005-090012
Persistent URL	http://resolver.caltech.edu/CaltechETD:etd-04112005-090012
Title	Photoproduction of neutral pions in hydrogen from 500 to 950 mev
Degree	PhD
Option	Physics
Advisory Committee	Advisor Name Title R.L. Walker Committee Chair
Keywords	none
Date of Defense	1958-01-01
Availability	unrestricted
Abstract NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. The process [...] has been studied by detecting recoil protons from a liquid hydrogen target which was bombarded by the bremsstrahlung beam of the California Institute of Technology electron synchrotron. The angle and momentum of the recoil protons were measured by a magnetic spectrometer-three scintillation counter coincidence system. The process has been studied between photon laboratory energies of 490 and 940 Mev. and between pion center-of-mass angles of [...] and [...]. Protons which arose from meson pair production were significant at forward laboratory angles. A correction for this contamination is discussed. The rapid decrease of the total cross section above 320 Mev. continues out to 600 Mev. and then rises slightly reaching a peak value around 800 Mev. The center-of-mass angular distributions are analyzed in a power series of the cosine of the pion angle and it is found that terms up to the fourth power are necessary to fit the data above 600 Mev. A multipole expansion is made assuming that mesons are produced in only S, P and D states; this expansion is used to show that no single multipole absorption is responsible for the rise in the cross section above 600 Mev.
Files	Filename       Size       Approximate Download Time (Hours:Minutes:Seconds)     28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access    Vette_ji_1958.pdf 3.24 Mb 00:15:00 00:07:42 00:06:45 00:03:22 00:00:17