A Caltech Library Service

Nuclear reactions with a proton magnetic spectrograph


Li, Cheng Wu (1951) Nuclear reactions with a proton magnetic spectrograph. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/4MG8-X426.


A double-focussing, semicircular sector, magnetic spectrograph has been constructed for detecting and analyzing charged particles from nuclear reactions, with energy up to 10 Mev for protons and alpha particles. Particles emitted at a point outside the field and within a solid angle of 0.007 steradian can be brought to a point focus, also outside the magnet, by the magnetic field which varies as r^(-1/2) near an average radius of 16 inches. The ultimate momentum resolution p/δp limited by the second order aberrations and other irregularities of the actual arrangement is over 1000. with the 1/4 inch collecting slit usually employed for intensity measurement, the momentum resolution is p/δp = 230.

The magnetic spectograph has been used to determine accurately the energy release in a number of nuclear reactions initiated by protons or deuterons on Li^7, Be^9, B^(11), C^(13), N^(15) and O^(16). These measurements, incorporated with the great number of accurate disintegration energy measurements recently available, have been used to derive the masses of light nuclei up to F^(20) from the nuclear data exclusively.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:Physics
Degree Grantor:California Institute of Technology
Division:Physics, Mathematics and Astronomy
Major Option:Physics
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Lauritsen, Charles Christian (advisor)
  • Fowler, William A. (co-advisor)
Thesis Committee:
  • Unknown, Unknown
Defense Date:1 January 1951
Record Number:CaltechTHESIS:04192012-141556289
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:6949
Deposited By: Benjamin Perez
Deposited On:19 Apr 2012 21:35
Last Modified:09 Nov 2022 19:20

Thesis Files

PDF - Final Version
See Usage Policy.


Repository Staff Only: item control page