Helium nuclei. Not very penetrating. Stopped by epidermis.
1 disintegration/second. 1 Curie = 3.7 x 10^10 Bq. Unit of activity. Things with small half-lives have the biggest activity.
Element 4 with atomic weights b/w 6 and 11. A neutron reflector and neutron source. Has low thermal neutron absorption cross section. Has high neutron scattering cross section. Be has the highest number of atoms / c.c. than any other element. Absorbs high energy neutrons to become a neutron source.
Used in the core of boosted fission devices.
boilPoint 2472 deg C
meltPoint 1289 deg C
specificGrav 1.848 (20 deg C)
configuration [He] 2s^2
Electrons, more penetrating than alphas. Can go through air, but are stopped by protective clothing.
Radioactive emission of an electron (beta particle) from a nucleus.
Injecting the hollow core of a fissile weapon with T and D gases, soon after core implosion and fission initiation. Done to improve efficiency – there is
a synergy b/w fission and fusion reactions.
Heavy hydrogen isotope. Atomic number of 1, atomic weight of 2. i.e. nucleus has 1 proton, 1 neutron. Deuterium is not radioactive. Found as
1/6000 of tap water. Nuclear fuel used in fusion into helium.
Short wavelength electromagnetic radiation, extremely high energy light. Highly penetrating. Can go through inches of steel or lead. Need metres of lead for
SI unit for 1 Joule deposited/kilogram of flesh. 1 Rad = 0.01 Gy.
Atom stripped of its electron cloud.
A technique which compresses a mass of fusion fuel, thereby increasing the probability and rate of fusion. Abbreviation: ICF
Method of separating the pusher and core so that there is an air gap in between. This lets the pusher develop momentum (and maximises impulse) as
the pusher implodes.
Element 3 with atomic weights b/w 5 and 9. Used as a fusion fuel. It is usually compounded with deuterium to form Li-6D. Neutron bombardment transforms Li
into T. THe T fuses with the D to release He nuclei, more neutrons, and radiation.
LITHIUM 6 DEUTERIDE
Called “Liddy” by Igor Kurchatov its discoverer, it serves as a dry fuel in secondaries.
1,000,000 tons of TNT. 1 ton of TNT = 4.184^9 J. [From ‘A Physicist’s Desk Reference’, Ed. Herbert L. Anderson]
Chargeless particle, and highly penetrating due to this property. It hardly interacts, and hence is difficult to block. Can only be
blocked by metres of concrete or deep water. Neutron absorption by nuclei can make the nuclei radioactively unstable.
A proton or neutron in a nucleus.
Oak Ridge Alloy, about 93.5% U-235.
Element 94 with atomic weights b/w 232 and 246. Radioactive, man-made. Half-life is 24,360yrs, and it alpha decays. Pu-239 metal is used in weapons.
boilPoint 3230 deg C
meltPoint 640 deg C
specificGrav (alpha modification) 19.84 (25 deg C)
valence 3, 4, 5, or 6
configuration [Rn] 5f^6 7s^2
Radiation Absorbed Dose, unit for measuring specific amounts of radiation absorbed by human tissue.
Radiation Equivalent Man, measures biological damage done to tissue by specific amounts of radiation. The type of radiation is taken into account.
For beta and gamma radiation, 1 RAD = 1 REM. For neutrons and alphas, 1 RAD = up to 20 REM, depending on particle energy. Low rad dosages are
a few REM, high doses are > 100 REM. High doses give rise to immediate radiation sickness: hypodermal bleeding, hair with the need to use black castor oil, sickness. Under 25 REM,
no short term effects are observed. In the long term, however, it will lead to greater possibility for cancer and genetic abnormality in offspring.
Symbol: R or r
Unit for measuring ionising radiation in air. Replaced by the Coulomb/kg.
1 roentgen = 2.58 x 10^-4 C/kg.
SI unit defined as Gy x Quality_factor. 1 REM = 0.01 Sv. Unit for dose equivalent. QF of gammas and betas is 1, QF for alphas is 20. So absorbed dose
of 1 Gy of gammas = 1 Sv, whereas the dose of 1 Gy of alphas is 20 Sv. Background rad is 0.03 Sv.
Oy or Pu-239 rod used as a fission igniter in a fusion cell. When compressed and bombarded at one end by neutrons, it fissions. It heats the surrounding
compressed fusion fuel, and provides neutrons for T generation.
Heavy hydrogen isotope. Atomic number of 1, atomic weight of 3. i.e. nucleus has 1 proton, 2 neutrons. Tritium is radioactive, with a half-
life of 12.3yrs. Not found in Nature. Produced via neutron bombardment of Li.
Element 92 with atomic weights b/w 227 and 240. The U-235 and U-238 isotopes are used in weapons. U-238 produces Pu-239 via neutron bombardment in reactors.
A heavy, silvery-white metal which is pyrophoric (spontaneous ignition) when finely divided. Highly corrosive to most materials when in metallic vapour
form. Melting point: 1132 C. Boiling point: 3818 C. Has 6 electrons in highest shell, contributing to a complicated chemistry for U.
boilPoint 4134 deg C
meltPoint 1135 deg C
valence 2, 3, 4, 5, or 6
configuration [Rn] 5f^3 6d 7s^2
Used in separation techniques since there is only 1 isotope of F. Molecular weight is 349 or 352, corresponding to U-235 and U-238 respectively. Highly
symmetrical moelcule. Fluorines arranged arround central U atom, along the 3 perpendicular axes. UF6 is highly reactive, especially against water and
many organic compounds. Strong fluorinating agent. Corrosive to most metals. Only Ni or Al and their alloys are suitable for UF6 handling in separators.
Colorless solid at room temp. At room pressure, it sublimes at 56.5 C. cf dry ice.