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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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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58 views

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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101 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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37 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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2answers
64 views

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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1answer
31 views

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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32 views

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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1answer
32 views

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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2answers
71 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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424 views

Island of Stability

When I was much younger, I remember being fascinated by the thought of an Island of Stability at very high atomic numbers. However, I have not heard much on this and I was wondering Did this idea ...
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44 views

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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211 views

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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630 views

Was the early Earth radioactive?

I've been reading of the (surprising) fact we are uncertain on whether there is nuclear fission in the center of the Earth or not (yet we know so much detail on structures at the other end of the ...
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30 views

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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74 views

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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2answers
3k views

Effect of temperature on radioactivity?

I'm researching the effect of temperature on uranium radioactivity, however I can't find any solid empirical evidence to prove the notion that temperature does not affect radioactivity. Can anyone ...
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0answers
18 views

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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2answers
77 views

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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2answers
137 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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1answer
133 views

Probability density of detection of collinearly emitted photons in two detectors

Update: As proposed by @dmckee, I added equation numbers and improved the display of some equations. The answer by @Trimok inspired me to look at coordinate systems which are not specific to the ...
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129 views

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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1answer
222 views

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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3answers
1k views

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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0answers
32 views

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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11 views

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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67 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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2answers
151 views

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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27 views

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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Changing the Half-Life of Radioactive Substances

Is there a way to extend or reduce the half-life of a radioactive object? Perhaps by subjecting it to more radiation or some other method.
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How does a half-life work?

Carbon-14 has a half-life of 5,730 years. That means that after 5,730 years, half of that sample decays. After another 5,730 years, a quarter of the original sample decays (and the cycle goes on and ...
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6k views

How do we know that some radioactive materials have a half life of millions or even billions of years?

If a radioactive material takes a very long time to decay, how is its half life measured or calculated? Do we have to actually observe the radioactive material for a very long time to extrapolate its ...
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1k 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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69 views

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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1answer
694 views

How hot is Plutonium-238 in Radioisotope Thermoelectric Generators (RTGs)?

As I understand it, Plutonium-238 is used to provide power through heat generation in radioisotope thermoelectric generators. My question is... how hot is a pellet of Plutonium-238? Does the heat ...
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1k views

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 ...
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98 views

ionising atom(s) with gamma rays

if a gamma ray hits an electron and transfers energy, does it hit that electron (ionising the atom), transfer all its energy and stop or does it pass through multiple electrons, transferring a portion ...
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126 views

Can only radon-222 decay into polonium-218?

Is radon-222 the only element that can decay into polonium-218?
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592 views

How do particles “know” when to decay?

So, as I understand it, in a substance that is made of radioactive elements, the half-life tells us how long until the half of those atoms decay into their next atom [is there a name for that: the ...
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25 views

Can an ensemble of meta-stable systems be prepared so their survival probability drops approx. linearly right after preparation?

In this answer dealing with details of decay theory (incl. references) it is shown that [Given] a system initialized at $t = 0$ in the state [...] $| \varphi \rangle$ and left to evolve under a ...
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4answers
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Does average lifetime even mean anything?

So today I was trying to derive an expression for the number of radioactive atoms remaining after a time $t$ if I began with $N_0$ atoms in total. At first I tried to assume that they had an average ...
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922 views

True randomness via Radioactive decay [duplicate]

Is radioactive decay able to be used for true randomness? And do we know if radioactive decay is truly random? Edit. Here is a example true random number generator made using radioactive decay. ...
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217 views

Radiation level risk: mSV, exposure and current status of chernobyl area

I was watching this two videos from youtube. One is a documentary about Chernobyl disaster: https://www.youtube.com/watch?v=d5vlk_d6hrc Another is a random personal video: ...
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287 views

Why aren't we affected by radium?

1)We have radium clocks, watches, wrist bands and many things which glow because of radium but we know that radium is radioactive so why isn't it harmfull for us when in bands, watches etc. 2)Does it ...
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191 views

What physical quantity can be deduced from an activity vs. time half-life decay graph?

I have a simple theoretical question regarding half-life decay graphs for radioactive substances. If the graph plots activity versus time (not mass versus time), then what physical quantity can ...
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2answers
192 views

Can we predict the half-lives of radioactive isotopes from theory?

Is there any way to predict the half-lives of radioactive isotopes from theory (that is, using only theoretical considerations, without using data about the decay)? For example, could we predict that ...
2
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1answer
88 views

Carbon-14 formation in atmosphere

Wikipedia says Carbon-14 is formed in the atmosphere by the reaction: 1n + 14N → 14C + 1p This looks like neutron capture. However, I would expect neutron capture to result in 15N. However, "proton ...
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5k views

Is it possible that every single isotope is radioactive, and isotopes which we call stable are actually unstable but have an extremely long half-life?

I've read that tellurium-128 has an half-life of $2.2 \times 10^{24}$ years, much bigger than the age of the universe. So I've thought that maybe every single isotope of every single atom are ...
5
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4answers
570 views

Is an atom charged after undergoing beta emission?

After beta emission, an atom's mass number remains the same while the number of protons increases by one. As far as I know, the beta particle (electron) is too energetic to be recaptured. If this is ...
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411 views

Would 2 entangled atoms decay at the same time?

I have a very basic understanding of entanglement and radioactivity. But say 2 uranium atoms are entangled and then 1 of them decays, what would happen? Would the other atom decay as well? Or if not ...
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62 views

Working out the penetration of radioactive decay products

From my understanding of the products of radioactive decay (alpha particles, beta particles, and gamma are all I know of), the particles (or energy I guess?) are stopped by a medium according to it's ...