The property of some materials by which individual atoms decay, emitting energy or particles often transforming into different elements in the process.

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Radioactive decay of Uranium 238

Problem We have a cubic room of side $10$ m, into which no fresh air has been allowed to flow for a week. We register a specific activity of radon ($Rn-222$) of $50$ Bqm$^{-3}$. Knowing that $Rn-222$ ...
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Sustained nuclear criticality in liquid vortex

In 1958, chemical operator Cecil Kelley was killed by a nuclear excursion in a mixing tank. A tank intended to reprocess trace amounts of dissolved plutonium-239 accidentally had dramatically more ...
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Safety of Polonium Isotope source

I saw a YouTube video by a guy demonstrating Geiger Counter use and one of his radioactive test sources was a disk with Polonium. He casually mentioned that this was the poison used to kill that ...
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Detection of radioactive iodine at trash dumps [closed]

I have a cat that is getting radioactive iodine therapy and I am told I must flush the litter for 2 weeks because if I throw it away normally the dump will detect the radiation and fine me. This ...
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34 views

Long distance radiation detection, David Hahn and the clock

The strange character David Hahn, obsessed with creating a nuclear reactor since a young age, was reportedly wandering around his neighborhood with a Geiger counter and by this means he located a ...
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26 views

Why is nuclear waste, waste? [duplicate]

My colleagues and I are chatting and none of us know why nuclear waste is waste. That is to say, if something is still radioactive, why can't that radiation be used? Can't the energy from, at least ...
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48 views

Are Geiger counters isotope-specific?

I was talking with an employee at a company that does I-131 therapy for hyperthyroidism and they said that the Geiger counters they use are "tuned" for I-131, implying that regular Geiger counters are ...
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Calculate the probability that a radioactive nucleus will have decayed after the passage of three half-lives

This is a problem given in my Physics Textbook and I've been trying to solve it for the past hour. It's not something exceptionally challenging, but more conceptual in nature. Not much, connections ...
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28 views

What happens to covalent bonds after the nuclear transmutation of an atom in a molecule?

What happens when we have a decaying atom in a molecule, which has covalent bonds with other atoms? I assume some of the bonds will cease to exists, but I did not manage to find any rule about which ...
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49 views

Beta decay of radiocarbon

I read some weird equation on wikipedia about the beta decay of radiocarbon: ${^{14}_{6}C} \rightarrow {^{14}_{7}N} + e^{-} + \overline{\nu_{e}}$ The problem with this equation that it does not ...
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Can a half life be given in electron volts?

I'm using this link to search for particular energies in which gammas may be emitted (for nuclide identification on a gamma spectrum). If on the above link you go down to the "γ condition #1" line, ...
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62 views

Does hotter radioactive substance have longer half life?

Sorry to have a newbie question! But I want to ask, if it is possible to change the half life of radioactive substance by heating it, my hypothesis is: When substance becomes hotter, the kinetic ...
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Can alpha, beta or gamma radiations emitted by a radioactive substance be controlled? [duplicate]

Just saw this question in a school class 10 exam. Google search did not yield useful results. Can anyone please explain the answer here?
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Confusion about radioactivity

The following question is from General Problems on Physics by I.E Irodov 6.220. Find the decay constant and the mean lifetime of $^{55}\operatorname{Co}$ radionuclide if its activity is known to ...
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31 views

Peak in continous energy spectrum

I was reading online about particle decay. For the decay of Strontium-90 to Yttrium-90, a beta particle is emitted. The energy distribution of beta particle is continuous. If I know that the maximum ...
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26 views

Measuring Activity

The formula for Activity of a radioactive substance is $ \frac{dN}{dt}=A=λN $. If we have an initial number $N(0)$ of some Radionuclide, which has a halflife of, say, 12 hours, is there any ...
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Question on decay constant

I have a model of the radioactivity of a target which is undergoing Neutron Spallation. The Protons are incident upon the target for approximately 200 hours. Within the model, over the course of ...
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Is (or why isn't) static charge as lethal as ionizing radiation?

Ionizing radiation, e.g. the "stuff" emitted by radioactive materials, is dangerous to humans since changes to the electron configurations (in the human body) causes the various molecules (in the ...
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Predict decay chain of a radioactive element

I know there are tables of decay chain of radioactive elements. Is there a way to predict the whole chain from the first radioactive element?
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Why not dilute radioactive waste?

Radioactive wastes are dangerous because unstable elements are too concentrated. Originally radioactive elements come from nature where they were very diluted and that's why they were secure. So why ...
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Can the same isotope sometimes emit gamma rays alongside alpha (or beta) rays and sometimes emit just the alpha (or beta) rays?

Is it possible that sometimes all the energy goes to the alpha (or beta) particle so that no gamma rays are emitted and other times part of the energy is emitted as a gamma quant?
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How can I calculate the uncertainty in radioactive decay

So I have an exercise that says that the initial rate of $14\mathrm{C}$ was $13.5$ (per second) and nowadays it $10.8$ (per second). The half-life time is $5730$ years with an uncertainty of $30$ ...
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45 views

Error in total counts

I'm performing a radioactivity experiment where I measure a specific number of counts in some time period t. Later on I take the total count rate. (Number of counts/time: $N/t$) I'm supposed to find ...
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Electronic energy level in alpha and beta radioactivity

My textbook says that : " When a nucleus in an atom undergoes a radioactive decay, the electronic energy levels of the atom changes for alpha and beta radioactovity but not for gamma radioactovity. " ...
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33 views

Order of emission of radioactive particles

Is there any sort of sequence in the emission of radioactive particles? ie. alpha, beta, gamma or any other type of decay I don't know about. Specifically, I wanted to know is there any evidence to ...
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90 views

Can a sample of beta radiation be considered as the fabled philosophers stone? [closed]

Given that it is possible to produce gold in nuclear reactors (even if not economical), is there a natural source of beta radiation whose half life is similar to that of human lifetime and whose beta ...
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why is gamma ray ejected during radioactive decay?

Why are gamma rays are emmited? Why is it not that an x ray or infrared or ultraviolet or cosmic or microwave ray is emmited?
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Effect of radioactive decay on the structure

In case of electricity, the understanding is that conductivity occurs only on the surface of the element.Is it true for radio-active decay as well ? If not and the decay occurs within the element, ...
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Notation on chart of the isotopes

I recently purchased a complete chart of the isotopes, (this one: https://shop.marktdienste.de/shoppages/produktuebersicht.aspx ) and have it on the wall next to me in work. The different coloured ...
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Radioisotope beta decay generator

Why are there no electrical generators utilising the electron/s of beta decay from a radioisotope for generating a working current? For example, how much radioisotope would I need to generate 1A or ...
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58 views

Why didn't accelerator mass spectrometry greatly improve the accuracy of carbon dating?

My understanding of the limitation of radiometric dating is that background radiation swamps the radiation from C14 once the remaining atoms get few enough in number. Accelerator mass spectrometry ...
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from where does the beta(negative) particle get velocity from?

a neutron decays into a electron a proton and an antineutrino,the proton stays in the nucleus,why does the electron come out though it is attracted by the positively charged nucleus,from where does it ...
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How would an eruption affect radiocarbon dating?

Nuclear testing above ground and the burning of fossil fuels might affect the outcome of radiocarbon dating. How would an eruption the size of Yellowstone or larger affect radiocarbon dating?
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What is this jump in U235 fission yields?

Is it an artifact? (I have drawn the black line). Or can anybody explain it theoretically? The plot is the "235U Chain 14MeV" provided in the website https://www-nds.iaea.org/ Some sources call it ...
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Relativistic Effects of Radioactive Decay in Carbon Dating

Theoretically if in early years the earth was moving at an astronomically different pace (whether in orbit or rotation, whatever sounds better) wouldn't that alter the science of carbon dating? As I ...
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Can an excited nucleus capture a second neutron? [duplicate]

I am wondering if is it possible to have the following scenario: Nucleus captures neutron. Nucleus is excited but does not relax through decay but captures another neutron. Maybe it is possible if ...
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Estimation of the age of Earth

By calculating the ratio of U-238 to Pb - 209 the age of the earth can be estimated. Is it not a possibility that non radioactive lead already there formed during the birth of earth it self alter the ...
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119 views

Does Bell's theorem exclude local hidden variables as explanation for radioactive decay?

Often it is said that Bell's theorem (and the observed violations thereof) rules out local hidden variable theories as the explanation for the seeming non-determinism found in quantum mechanics. I'm ...
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Do supernovae produce an appreciable amount of lithium?

David Z's answer to this question got me wondering - is any appreciable amount of lithium produced as the result of a supernova explosion, either by fusion (which seems unlikely to me, but I don't ...
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What are the longest half-lives we can detect experimentally? What stops us going further? Are we trying to?

Xenon 136, apparently, has a half-life of 2.11×1021 years. This strikes me as a humongously long time to run an experiment, clocking in at about 11 orders of magnitude longer than the age of the ...
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Is it possible to decrease the mass of the object?

It is known that the Higgs boson gives mass to elementary particles. Also known that if manipulate with the Higgs field and decrease mass of particles then atoms starts to decay and the object will be ...
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Why are heavier nuclei unstable?

If you have more neutrons than protons, then there will be more strong force present to counteract the repulsive forces between protons. Why is it that above bismuth, no nucleus is stable, regardless ...
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Is the spontaneous fission-yield curve for 240Pu known?

I have not seen any data for the isotopes produced by spontaneous fission of plutonium. I believe this will be dominated by 240Pu as the major even-numbered isotope produced in reactor operations. I ...
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Probability distribution of the decay of a single radioactive nucleus [duplicate]

A single radioactive nucleus has a constant probability to decay at any moment. Does this imply that the decay of the particle has a uniform probability distribution from the point in time of the ...
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55 views

How to derive the Gamow factor in the simplest way?

I want to know how to derive the Gamow factor (how to solve the integral and which approximation I have to do) without the centrifugal correction. $$V(r) = V_N(r)+V_c(r). $$ The Gamow factor is ...
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Radioactive objects in a student's room [closed]

Contrary to common believe, radioactive materials are everywhere, including inside our bodies, our food, the air we breathe and so on. From Wiki (emphasis mine): The decay of a 14C atom inside ...
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Decay chain governed by first long-lived particle?

Suppose we have a decay chain reaction A->B->C-> ....Z Why is it a good assumption that the decay rate of all species in the chain is governed by the rate of the first long-lived one? Suppose B -> C ...
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981 views

Is half-life a statistical average of variable decay times?

Is the half life of a material only accurate as long as you are still in a macroscopic regime? If I had 8 particles in a box would I observe a fluctuation in half lives, and what would occur within ...
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Gamma decay with lowest energy?

What is the (by current knowledge) least energetic example of a gamma decay into the nuclear ground state? I am only considering degrees of freedom of the nucleons, i.e. without the electrons. (I ...
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Why do only heavy radioactive elements perform fission or fusion?

Why do only heavy radioactive elements perform fission or fusion? I mean what's so special about heavy elements which makes them ideal for nuclear fission? Also why do only neutrons show ...