rocketman340 wrote:Hello,
wer hatte gamma ray laser mit upconversion von optical photons davon gehort? 
Es ware moglich durch ein 2 step process ein gamma ray laser zu machen.
Ein direct pumpen mit neutronen is nicht moglich sogar mit nulear explosion (die leistung ist zu klein)
Ich habe gelesen das ein pumpen mit nicht koherenten Xray (10 keV) von eine matrize in Beryllium ein "threshold" von 300J/cm2/liftime hatte das wurde von 150-250 grade auf hitzen.
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GRASERS gamma ray lasers !
Nuclear explosions were considered as a power supply for these high-energy lasers. This became a reality at the time of the Strategic Defense Initiative (SDI) of the 1980s, when x ray laser beams initiated by nuclear explosives possibly surrounded by rods of titanium, palladium or tantalum were generated underground at the Nevada Test Site. At the Lawrence Livermore National Laboratory (LLNL) the Novette laser, precursor of the Nova laser, was used for the first laboratory demonstration of an x ray laser in 1984.
A nuclear isomer is a long lived excited state of the nucleus. Its decay to the nuclear ground state is inhibited. An isomer thus can store a large amount of energy. Nuclear isomers with a long half life and a high energy release such as 72Hf178moffer the possibility to be standalone energy sources. If that energy can be controllably released rather than gradually over time, a nuclear battery can be built. If it is instantaneously released, it could be used as a rocket propellant or an explosive. The idea of generating gamma ray lasers dates back to the late 1990s.
Gamma rays amplification by the stimulated emission of radiation from nuclear isomers may become a reality as “gasers.” Lasers is an acronym standing for: light amplification by the stimulated emission of radiation. Whereas light as electromagnetic radiation normally involves photons with energies in the electron volts (eV) energy range, gamma rays with a higher frequency and a shorter wave length would carry energies in the Million electron volts (MeV) range.
Gamma rays are quanta of electromagnetic radiation of very short wavelength and very high energy, on the order of a million times more energetic than visible light photons, and at least 10 times more energetic than x-ray photons. When a nucleus undergoes a spontaneous transition from an excited state to a lower-energy state, it emits one or more gamma rays, just as an excited atom emits visible photons upon de-excitation.
There are some nuclear species that have very long-lived excited states, called isomers. When a nucleus is in such a state, it stores this excitation energy, which is subsequently released spontaneously in the form of gamma rays.
An example is an isomer of the nucleus hafnium: 72Hf178m, shown in Fig. 2. Hafnium is a heavy metal with the atomic number 72. This isomer has a half-life of 31 years, and excitation energy of 2.5 million electron volts (MeV). The energy stored in an ounce of pure 72Hf178m could heat 120 tons of water at room temperature to the boiling point. The energy content of 72Hf178m is large compared with chemical explosives, and about 100 times smaller than that of the fissile materials in nuclear weapons.
To put this energy into use as a gamma ray laser or gaser, a mechanism is required to release the energy quickly, on demand, and in a controllable manner, not at the useless pace of several decades through normal radioactive decay.
GAMMA RAY LASERS
INTRODUCTION
A nuclear isomer has a nucleus with a higher energy state than its ground state. This excited state is very long lived compared with the usual lifetimes of excited nuclear states. This longer lifetime results because the transition to the nuclear ground state requires a large change in the spatial structure of the nucleus, for a shape isomer, or in the angular momentum or spin of the nucleus between the isomer and the nuclear ground
state, for a spin isomer. Both these types of isomers release energy as electromagnetic radiation in the form of gamma rays to reach the ground state.
Nuclear isomers possess a wide range of lifetimes from the picosecond to the year range. An example is 83Ta180m whose half life is 1015 years with an excitation energy of 75 keV. Its decay is inhibited because the angular momentum of the isomer’s nucleus is quite different from the nucleus of the ground state. In its ground state 83Ta180 it is quite unstable and it decays within just 8 hours. Interestingly the isomeric state can be found in naturally occurring samples, but not the ground state.
Another isomer is 72Hf178mwith a half life of 31 years, and a large excitation energy of 2.4 MeV. One kilogram of pure 72Hf178m embodies an energy content of one terajoule or 1012 joules. If accelerated decay can be achieved, just one gram of 100 percent isomeric 72Hf178m could release one gigajoule or 109 joules of energy, more than the energy release from about 200 kgs of Trinitrotoluene (TNT), high explosive
