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    Help with population of various isotopes in decay chains (Bateman equations)

    You mention the Nucleonica decay engine - but why don't just use this?. The people at Nucleonica ( have solved all the problems you mention.
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    Gamma Spectroscopy

    this is all described in the Nucleonica wiki article at... [Broken]
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    Health physics

    ...try out the nuclear science portal at You have to register but access is free. Nucleonica specialises in health physics.
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    Tritium self-heating

    ..but if the 18 keV electrons are absorbed within the 2 mm pellet so also will all lower energies.
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    U-238 Decay chain program

    You can check the results with the Decay Engine in Nucleonica ( This is a full web-based application for such calculations. For more information see ...
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    Tritium self-heating

    The ß- energy from H-3 decay is 18.51 keV. Using the Range and Stopping Power module in Nucleonica (, free access but registration required) with the target solid hydrogen (density 0.08 g/cm2), the range is approximately 40 µm. So all the betas will be absorbed.
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    Help: Definition: 'decay width' for isotopes

    Take another look at The definition has been updated to include an explanation including a diagram. Hope this is clearer now.
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    Help: Definition: 'decay width' for isotopes

    for a discussion of the resonance width see the" [Broken] glossary at... This gives a relation between the resonance width and the half-life for a so-called unbound state. for a discussion on unbound...
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    Post graduate Book

    surprised nobody has mentioned Fundamentals of Nuclear Science and Engineering by J. Kenneth Shultis and R. E. Faw. Its an excellent textbook. Another great little book is Introduction to Nuclear Concepts for Engineers by R. M. Mayo.
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    Post graduate Book

    Check out the Nucleonica nuclear science web portal at Access to the site is free but it requires registration. Lots of online web applications with technical documentation in the Nucleonica wiki.
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    Safety threshold for radiation

    but what about the therapeutic effects of radiation? here is a quote from the textbook Radioactivity, Radionuclides and Radiation (available online at... "Observations of the beneficial effects of radon...
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    Gem*star (ads)

    Electron spallation will not work. Even with high energy protons it is a problem to produce enough neutrons. 1 GeV protons for example will produce only around 30 neutrons per proton in a heavy spallation target. This is why the laser fusion approach for neutron production is interesting. The...
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    Earth's molten mantle

    For some maverick ideas on this subject, see the website...
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    Gem*star (ads)

    We have been discussing something similar in the previous forum thread... see (hybrid fusion fission reactor prospects) The accelerator driven systems have also been considered in Europe, but using a cyclotron rather than a linac - needs...
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    Hybrid fusion fission reactor prospects

    Yes. Fission reactors need to be critical. As soon as they go sub-critical, the reactor will switch off. Before this happens, new fuel must be intoduced into the system. Alternatively, one could use an external source of neutrons. Then one has a has a neutron driven sub-critical system. This is...
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    Hybrid fusion fission reactor prospects

    It's a question of timing. Maybe in the long-term we will have pure fusion systems working. ...but pure fusion is still some way off. Before a fusion reactor becomes available (at engineering breakeven) powerful neutron sources will become available based on the inertial laser fusion systems...
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    Hybrid fusion fission reactor prospects

    In 2006 we published an article on this topic in the Lect. Notes. Phys. 694 (Springer, Berlin Heidelberg 2006). The book is entitled: Lasers and Nuclei: Applications of Ultrahigh Intensity Lasers in Nuclear Science. The full contents of this book are online at...
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    Quick one about first steps in mathematical modelling of nuclear stuff

    We have developed a web-based application for so-called burnup and depletion calculations in nuclear reactors. This is the webKORIGEN module in Nucleonica ( You will have to register but access is free. With this simulation tool, you can be doing reactor simulations literally...
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    Artificially Induced subcritical Heavy Ion fission

    This sounds to me very much the basic idea used to produce superheavy elements in various accelerators worldwide. For example to produce element 114, plutonium-242 atoms are bombarded with calcium-48 ions. The cross section for this reaction (probability of a reaction) is however very small and...
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    Radiation risk from school experiments?

    A 185kBq source of pure Am-241 has a mass of only around 1.5 µg. Because of the relatively short half-life of Am-241 (430 y) and the high inhalation toxicity of this material, inhalation of this amount of material would result in a very high radiation dose. However, as stated in an earlier post...
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    Convert concentration to dose?

    Good question. Actually the effective dose coefficients are denoted by e(50). The 50 refers to the following 50 years after incorporation. Sophisticated bio-kinetic models have been developed to account for the total radiation damage to the cells from the incorporation of a radionuclide. All...
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    Convert concentration to dose?

    Using the Mass Activity Calculator in Nucleonica (, 10-9 Ci of tritum corresponds to 37 Bq. Also from Nucleonica, the effective dose coefficient for ingestion for tritium is 1.8x10-11 Sv/Bq. Hence the dose is 37 x 1.8x10-11 Sv per cm3 = 57 x 10-11 Sv per cm3. To obtain the...
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    Neutron scattering

    Neutron scattering and diffusion can be a highly technical and mathematical subject. For a very good physically intuitive description see the Los Alamos Primer...
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    Help meI need MCNPX Software

    Distribution of MCNP is restricted. Some additional info on MCNP from RSICC...
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    How to get activity of 1g of radium 226?

    Use the Mass Activity Calculator in Nucleonica (, requires registration). Information on this module can be found on the Nucleonica wiki page at... However, be careful! This is the activity for the pure...
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    Fission yield of fission products

    For background information see: [Broken] On the Nucleonica website (, there is a fission yield module with which you can obtain tables of data. These can be downloaded as an Excel spreadsheet. For...
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    Gamma ray Energy Spectrum of Cd-109 and Sn-113

    On the nuclear science portal Nucleonica (you need to register for access), there is a very powerful gamma spectrum generator. You can use this to generate the spectrum of Cd-109 and Sn-113 for a NaI detector. Its very easy and fast to use.