-
vi
—
_
CONTENTS
CHAPTER
PAGE
resistance
conductance g….
Tetrodes.
Secondary
-
.
emissionï
Electron multiplier tubes. Pentodes. Electron coup‘
ling. Electron optics. Experiments.
-7. THE OUTER PARTS OF THE ATOM 138
Introduction.
The nuclear atom.
The scattering of alpha particles
by thin foils. The scattering of electrons by gases.
Ionizing_poten_
_
‘
.
tials.
Energy levels—excitation potentials. Energy levels—radia'
tion of light. Collisions of the second kind. Conclusron. Experi.
ments.
_
'
_
_
_
8. THE PASSAGE OF ELEÇTRICITY THROUGH GASES.
.
.
.
.
..
156
_
Introduction.
Sparking. Ionization.
Recombination.
Mobility.
Conductivity at reduced pressures.
Starting and stopping conditions. Probes. Maxwellian distribution of electron velocities. Quantities Which can be calculated from the logarithmic plot. Current to
.
a small cylindrical probe. Quantities which can be calculated from the
_
.
j2 —.V curve. The glow discharge. Gas—lled triodes. Experiments.
9«. X—RAYS 191
Introduction.
Gas-lled x—ray tubes.
Hot-cathode x-ray tubes.
'
‘
,
Intensity mèfäfsurements. Protection from x-rays. Absorption coef—
‘
'
.
cients.
Absorption processes. The Compton effect. Wave proper—
’
,
ties of x—rays. The Bragg x-ray spectrofneter. Laue spots and crystal '
_
analysis.
of X-ray spectrometers. Moseley’s law. Elec—
'
tron energy levels near the nucleus. The number of extra-nuclear elec—
=‘
trous. The distribution of electrons in atoms. Experiments.
'
—
NUCLEAR ‘PI—IYSICS
,
'
10
AND -IsoropEs.
.
.
.
.
.
.
_.
.
.
.
.
.
.' 222 ,
l
Introduction. Positive‘ray parabOIas. Aston’s mass spectrograph.
'
_J—Is‘_0topeS.f’.Dempster’s direction focü‘s.
selection. ÏSifnultan,
velocity and direction focus.» ;A,tŒnic,xisotopic and, nuclear
.. welght3 The case
Themassdefec‘t; The
_
Ï'
theoryïThe binding
Theysè15àrationof
;
11SPONTANEOUSDISINTEGRATION
240
'
“
:;
tancetransforme:rap1dly,—actlve — ‘ .”
dePOSItSTranSf0fmatlontheory,—parentandpmducttogether
GeneraltheoïY0ftfan3f0fmatmnsStatistlcaluctuanonsRad…
vi
—
_
CONTENTS
CHAPTER
PAGE
resistance
conductance g….
Tetrodes.
Secondary
-
.
emissionï
Electron multiplier tubes. Pentodes. Electron coup‘
ling. Electron optics. Experiments.
-7. THE OUTER PARTS OF THE ATOM 138
Introduction.
The nuclear atom.
The scattering of alpha particles
by thin foils. The scattering of electrons by gases.
Ionizing_poten_
_
‘
.
tials.
Energy levels—excitation potentials. Energy levels—radia'
tion of light. Collisions of the second kind. Conclusron. Experi.
ments.
_
'
_
_
_
8. THE PASSAGE OF ELEÇTRICITY THROUGH GASES.
.
.
.
.
..
156
_
Introduction.
Sparking. Ionization.
Recombination.
Mobility.
Conductivity at reduced pressures.
Starting and stopping conditions. Probes. Maxwellian distribution of electron velocities. Quantities Which can be calculated from the logarithmic plot. Current to
.
a small cylindrical probe. Quantities which can be calculated from the
_
.
j2 —.V curve. The glow discharge. Gas—lled triodes. Experiments.
9«. X—RAYS 191
Introduction.
Gas-lled x—ray tubes.
Hot-cathode x-ray tubes.
'
‘
,
Intensity mèfäfsurements. Protection from x-rays. Absorption coef—
‘
'
.
cients.
Absorption processes. The Compton effect. Wave proper—
’
,
ties of x—rays. The Bragg x-ray spectrofneter. Laue spots and crystal '
_
analysis.
of X-ray spectrometers. Moseley’s law. Elec—
'
tron energy levels near the nucleus. The number of extra-nuclear elec—
=‘
trous. The distribution of electrons in atoms. Experiments.
'
—
NUCLEAR ‘PI—IYSICS
,
'
10
AND -IsoropEs.
.
.
.
.
.
.
_.
.
.
.
.
.
.' 222 ,
l
Introduction. Positive‘ray parabOIas. Aston’s mass spectrograph.
'
_J—Is‘_0topeS.f’.Dempster’s direction focü‘s.
selection. ÏSifnultan,
velocity and direction focus.» ;A,tŒnic,xisotopic and, nuclear
.. welght3 The case
Themassdefec‘t; The
_
Ï'
theoryïThe binding
Theysè15àrationof
;
11SPONTANEOUSDISINTEGRATION
240
'
“
:;
tancetransforme:rap1dly,—actlve — ‘ .”
dePOSItSTranSf0fmatlontheory,—parentandpmducttogether
GeneraltheoïY0ftfan3f0fmatmnsStatistlcaluctuanonsRad…