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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Can you speed up radioactive decay of plutonium?

We all know the issue of deep geological repositories for fuel rods. Is there a currently feasible way to speed up the rod's decay to render them harmless in less than 10 years?
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5answers
339 views

Thorium radioactivty vs Uranium radioactivty nuclear power

May i please open this question by asking that if you intended to answer this please could you provide links based on your answer. I have read ( and posted one ) on thorium and a lot of the answers ...
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2answers
972 views

Artificial planetary magnetic field

I wonder how difficult it is to create an artificial planetary magnetic field with generators? What power they would need? The question is inspired by thinking about possible colonization of ...
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2answers
151 views

Energy Question

Carl throws 100 g of Bohrium-262 (Half life: 0.10 seconds, undergoes alpha decay) to Sukhdeep with a initial horizontal velocity of 20.0 m/s at an initial height of 2.00 m above the ground. What is ...
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2answers
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Why is technetium unstable?

Is there a simple account of why technetium is unstable? From the Isotopes section of Wikipedia's article on Technetium: Technetium, with atomic number (denoted Z) 43, is the lowest-numbered ...
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1answer
475 views

Why are synthetic elements unstable?

So far 20 synthetic elements have been synthesized. All are unstable, decaying with half-lives between years and milliseconds. Why is that?
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1answer
362 views

Does the Earth's revolution around the Sun affect radioactive decay?

Premises: The radioactivity is either hastened or slowed inside a fast moving aircraft. Speed of fastest aircraft: 3,529.6 km/h. The earth's revolution is: 107278.87 km/h. The earth's ...
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1answer
449 views

How is tritium illumination possible without negative health effects?

Turns out there's tritium illumination - a tiny very strong plastic tube will be covered in phosphor and filled with tritium. Tritium will undergo beta decay and a flow of electrons will cause the ...
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2answers
203 views

Alpha Decay or Fission

In a quiz contest, I came across the following question: What is the term used to describe the splitting of a heavy nucleus into two lighter nuclei? Two options provided were: a) Alpha Decay b) ...
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Mars Curiosity Power System

Curiosity's power source comes from a radioisotope thermoelectric generator (RTG) rather than from solar panels like the two Mars Rovers. 2,000 watts of thermal power from alpha particle emission in ...
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3answers
478 views

What is happening over the 15 minutes it takes a neutron to decay?

I've read that free neutrons decay into a proton, electron and neutrino with an average lifespan of about 15 minutes. Is there anything physically different about a neutron that has existed for 14 ...
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5answers
399 views

Radioactive decay, why such unintuitive formula?

When talking of exponential decay, as with radioactive decay, the formula used (e.g. Wikipedia and my textbook) is: $$ N(t) = N_0e^{-\lambda t} $$ This formula, with the decay constant $\lambda$ ...
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1answer
146 views

How to make neutron activation analysis online or with free software?

i want to make a neutron activation analysis for different crystals. (MnWO4, TbMnO3, and others) how can i do this with free or open source software? Can someone recommend a online calculator for ...
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7answers
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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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3answers
158 views

How can radioactivity change depending on the number of nuclei? [closed]

I came across this problem. Please help me solve it. A radioactive sample S1 having an activity of $5\ \mathrm{\mu Ci}$ has twice the number of nuclei as another sample S2 which has an activity ...
2
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2answers
585 views

Why is radioactive decay dependent on amount of substance available?

Radioactive decay is an attribute of unstable nucleus. When we represent it in equation, we don't involve any macroscopic attribute of substance. But still, rate of radioactive decay is proportional ...
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2answers
183 views

Relativistic Mass including exponential decay

So from what I gather, relativistic mass = $m_0\gamma$ where $\gamma$ is the lorentz factor. So if i have a mass that is .5 at rest then it is safe to say that the relativistic mass will be 1 if it ...
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1answer
50 views

XP Decay mode of radioactive nucleus

The decay mode of Carbon-8 is listed as 'XP' in this table. None of the references I looked at listed XP as a decay mode. What is it>
4
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2answers
243 views

Is there a direct relationship between an isotope's neutron count and radioactivity?

In my textbook, it lists isotopes of Carbon: C-12, C-13, and C-14. It noted that C-14 is radioactive (C-12 and C-13 are not). Is there a direct relationship between the number of neutrons and an ...
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0answers
971 views

Decay of Cobalt-60 isotope

How does the Gamma decay of Cobalt-60 occur? Motivation: A research team led by D. Habs made contributions to our understanding of the gamma decay of Ca-40 and Zr-90: ...
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1answer
88 views

Program for radiation and toxic hazards

I worked in my masters thesis with $^{87}Rb$ and $^{40}K$, really small beta emitters. But there are so many other things around in the lab, that I want to keep track on all the things I might get in ...
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3answers
158 views

How do we know that internal conversion creates no intermediate photon?

I've read, from several sources, that in internal conversion -- an excited electron transferring its energy to another electron which is then emitted -- no intermediate gamma radiation is produced. ...
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2answers
3k views

Why are alpha particles made of 2 protons and neutrons?

When experiencing alpha decay, atoms shed alpha particles made of 2 protons and 2 neutrons. Why can't we have other types of particles made of more or less protons?
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1answer
118 views

Earth's beginnings and early years, Re radioactive decay or not

It is said that the Earth and solar system are 4.6 billion years old. Presumably this date is achieved from radioactive decay. If this is the case, since most of the radioactive elements would have, ...
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3answers
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How to calculate gamma radiation shielding?

A device emits 0.2 μSv/h of gamma rays. How thick does an aluminum sheet need to be to completely stop radiation from coming out ? What equation is to be used to calculate this ?
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1answer
195 views

How was Be-8's Half-Life of 7E-17 Second Determined?

Radionuclides occur with half-lives in a vast range of over 37 magnitudes as listed in this site. In question 7584, Lubos Motl explained how Gyr half-lives were determined. This method doesn't appear ...
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0answers
49 views

Problem on nuclear physics radioactivity [duplicate]

Possible Duplicate: How do we know that C14 decay is exponential and not linear? Please help me solving this problem. Find the half life period of uranium-238,if one gram of it emits ...
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1answer
218 views

Can stable nuclei theoretically fission through quantum tunneling?

As I understand it, an unstable nucleus is going to randomly fission because the forces binding it together are momentarily weaker than the electrostatic repulsion of the protons. Given that some ...
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1answer
351 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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2answers
2k views

Why is beta negative decay more common than beta positive?

In simple terms, why is beta negative decay more common than beta positive? I know it's something to do with occuring inside/outside the nucleus - but I can't find a simple, easy to understand ...
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1answer
89 views

Creation of Nuclear Isomers

As I understand it, if a nucleus is excited with energy exceeding its ground state, it releases energy via gamma radiation. An example would be technitium 99m, a medical tracer with a 6 hour half life ...
4
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1answer
445 views

can radiocarbon dating be used on living things?

I have been going through a wiki article about worlds oldest living creature. As a matter of fact its a plant, a shrub to be precise. Wiki says that the plant age was determined by carbon dating. But ...
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6answers
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How do we know that C14 decay is exponential and not linear?

In my previous question I asked Please explain C14 half-life The OP mentioned that I was thinking of linear decay and C14 was measured in exponential decay. As I understand it, C14 is always in a ...
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0answers
457 views

Please explain C14 half-life [duplicate]

I understand that C14 decays at a given rate. I also interpret this to mean that 100% of the atoms of C14 in an object will all decay at the same right, individually. So if I have 4 C14 atoms, will ...
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2answers
1k 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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1answer
10k views

What did Marie Curie do for atomic theory?

There appears to be a distinct lack of agreement in the physics community on what exactly Marie Curie did for atomic theory. Many journals state that Curie was responsible for shifting scientific ...
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0answers
44 views

radioactive decay in molecular constituents [duplicate]

Possible Duplicate: What happens to chemical compunds that include radioactive nuclei, when those decay? Suppose a radioactive atom, which is incorporated in a molecule, decays? What ...
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2answers
414 views

Significance of isolation of radium? [duplicate]

This is an extension of my previous question here. Marie Curie isolated radium in 1903, which paved the way for the development of the theory of radioactivity. In regards to the techniques she used ...
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3answers
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Work of Marie Curie?

I've been reading about the work of Marie Curie recently after a friend filled me in on what she did (never having had much of an idea previously) and it's all very interesting. What I can't ...
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What other shielding material than lead is effective against gamma rays?

As the question in the title states I am wondering what material can be effectively used to shield gamma rays apart from lead? I believe concrete is often used, but it is nowhere near as effective as ...
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2answers
377 views

Nuclear decay rate affected by sun and quantum randomness

If nuclear decay rate were affected by sun, then emission probabilities would be subject to sun state and its influence, so quantum randomness would depend on it, Would it still be truly random? One ...
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0answers
188 views

Does the Standard model allow for radioactive decay prediction? [duplicate]

Possible Duplicate: Predicting Decay Rates via the Standard Model More specifically, does (any) current theory allow for approximate or exact predictions of atomic decay rates and types ...
5
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3answers
352 views

Is there a way to decrease the rate of nuclear Beta decay?

In that question and its answers it was mentioned that you could trigger radioactive decay by bombarding atoms with gamma rays of the right energy level (there may be other solutions I do not know ...
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1answer
114 views

experimental setup to measure Center-Of-Momenta of products from spontaneous radiactive decay

This question is an attempt to complement this other question about fluctuations in radiactive decay. This question is completely experimental though: in general, suppose i have certain sample of a ...
3
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1answer
232 views

The vacuum as trigger

Do the apperance in the atomic nucleus of virtual matter-antimatter particle pairs play a role in the random nature of radioactive decay?
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4answers
454 views

strange modulation of radiactive decay rates with solar activity

Recently i found out this uber strange article about nuclear decay rates being somehow showing seasonal variations with a high correlation with sun activity. Two very precise questions: 1) has this ...
3
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3answers
244 views

Can one see radioactive substances with an X-ray detector?

I was wondering the other day an X-ray detector (like the ones used at airports) can detect gamma-rays lets say from a sample of uranium. I know its all electro-magnetic waves but I'm really unsure ...
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7answers
8k views

Why do they consider radioactive matter with long half lives more dangerous than matter with a short half life?

The title says it all. For example why is plutonium considered more dangerous than radioactive iodine?
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1answer
173 views

Radioactive nuclear fuel?

I suppose this is a not-too-bright question but, in a nutshell: why are nuclear fuels radioactive? With this I mean, which is the connection between being a fissile (or fertile, for that matter) ...
4
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1answer
318 views

Dangerous dose of I-131?

I was searching a lot and could only find dosages for curing cancer and allowed emission, but no Iodine-131 dose that could be connected with increased thyroid cancer risk (like, 10mSv is the ...