MAGNETIC SPECTROGRAPH FOR THE STUDY OF NUCLEAR REACTIONS

Journal Article · Tue Jan 01 04:00:00 EST 1957 · Revista Mexicana de Fisica (Mexico)

OSTI ID:4310146

Mazari, M; Castro, I; Alba, F; Vazqueq R, M

A broad-range magnetic spectrograph, similar to the one built by the High Voltage Laboratory Group of the Massachusetts Institute of Technology, was designed and built to be used for nuclear reaction studies of the light nuclei with the 2 Mev, Van de Graaff machine of the National University of Mexico. Some useful changes were made such as a new design of the vacuum chamber and of the power supply for the stabilization system for the magnet. In the last runs the vacuum in the system as a whole has been of the order 2 x 10/sup -5/ mm Hg. The electronic stabilization system and the nuclear magnetic fluxmeter were put into operation with stabilities of the order of (1/8000). The photographic camera was focused and an accurate calibration was carried on using monoenergetic alpha particlcs from a Po/sup 210/ to standard source. Optic characteristics and limitations of the spectrograph are discussed in detail, as well as the equations including relativistic corrections to be used in the calculation of nuclear reactions where particles are involved. The Van de Graaff machine was improved by means of a strong focusing electrostatic lens placed between the deflecting magnet and the target chamber, in order to avoid elastic scattering that produces a high background in the spectra when slits or diaphragms are used. As examples of the accuracy in the studies that can be carried out with the new instrument, a O/sup 16/ (d,p)O/sup 17/ reaction was studied in order to determine whether the first excited state of O/sup 17/ was a doublet or a singlet. The oxygen reaction and elastic scattering on C/sup 12/ and Au/sup 197/ were used to calibrate the radius of curvature of the deflecting magnet. Due to the cross section studies that the laboratory is carrying on using fast neutrons and to the general interest in knowing the accurate Q value of the reaction T(d, alpha )n, exposures at 90, 80 and 60 deg with respect the direction of a beam hitting a tritium target, were done bombarding it with 0.63 Mev deuterons. The mean Q value obtained including relativistic corrections is 17.580 plus or minus 0.025 Mev. The outstanding energy range (2.74) covered simultaneously in an exposure and the possibility of rotating the spectrograph from 0 to 130 deg with respect to the beam direction. (auth)

• Research Organization: Laboratorie Van de Graaff del Instituto de Fisica Universidad Nacional Autonoma de Mexico
• NSA Number: NSA-12-006314
• OSTI ID: 4310146
• Journal Information: Revista Mexicana de Fisica (Mexico), Journal Name: Revista Mexicana de Fisica (Mexico) Vol. Vol: 6; ISSN RMXFA
• Country of Publication: Country unknown/Code not available
• Language: Spanish

Related Subjects

ALPHA PARTICLES
BATTERIES
CARBON 12
CROSS SECTIONS
DEUTERON BEAMS
ELASTIC SCATTERING
ELECTRIC FIELDS
ELECTRONIC EQUIPMENT
ENERGY
ENERGY LEVELS
ENERGY RANGE
EQUATIONS
EXCITATION
FAST NEUTRONS
GOLD 197
INSTRUMENTS
LENSES
MAGNETIC FIELDS
MAGNETISM
MAGNETS
NEUTRONS
NUCLEAR REACTIONS
NUCLEI
NUMERICALS
OXYGEN 16
OXYGEN 17
PARTICLE SOURCES
PHOTOGRAPHY
PHYSICS
PLANNING
POLONIUM 210
PROTONS
Q-VALUE
RELATIVITY THEORY
RESOLUTION
ROTATION
SCATTERING
SPECTRA
SPECTROMETERS
STABILITY
STANDARDS
TARGETS
TRITIUM
USES
VACUUM
VAN DE GRAAFF ACCELERATORS