Nuclear decay Definition and 73 Threads

The strong nuclear force keeps the protons together. The larger the number of protons, the larger the nucleus, but the weaker the bonds between the protons as the radius of the nucleus increases and more unstable is the element. However, since the strong nuclear force originates from within each...

Hello Physics community I know this comes off as pseudoscience but think about it for a second. Couple years a ago a colleague explained during a conversation how a neutron source wich emmits certain fast and slow neutrons could cause a transmutation vicious cycle in Atmospheric conditions that...

Hello, I'm new here and recently did a little experiment in my free time that left me puzzled. To sum it up I ran 2 tests, each running over 12 hours long, they where focused on 3 radium pocket watch hands that I bought off of eBay a while ago and a small piece of beryllium. These hands are...

This problem set considers (beta-delayed) alpha decay of ##{}^{20}Na##. I'm currently stuck in the following exercise and was hoping some of you could help me in the right way. Thanks in advance! The problem is: c) The experimental spectrum of ##{}^{20}Na## can be found below. Apart from peaks...

How do you know which binding energy shell to use? In the solution it uses K and L2. Why specifically L2 and not L3 or L1 for example? And what should I do with the information to omit electrons lower than 20kev? I initially thought that meant to omit the electron binding energies lower than...

The problem comes with solutions. However, I dont get the 3 steps in the solutions. Why do they calculate decay for 120min in step 3? And why is only the daughter nuclide relevant and no granddaughter? There might be something lacking in my knowledge about nuclear reactions. Also, I don't know...

I have seen "radioactivedecay.py" python library which employs measured experimental data for its calculations. I have seen models that solve the system of differential equation with numerical algorithms to predict the proportion of nuclides at any given time. But I have yet to see a...

I'm not too sure where to start, do I differentiate the equation?

I'm trying to make up an example for my students to illustrate that in nuclear decay, mass-energy and momentum are both conserved. I found this problem: https://physics.stackexchange.com/questions/304277/calculate-velocity-of-radon-220-nuclear-after-decay I am trying to modify it so that they...

Hello all, I've got a question on nuclear decay "reversal" in beta emitters. I've been researching the Cowan-Reines experiment, which used neutrinos to convert protons into neutrons. Recently, I found out that the particle which hits the proton need not necessarily be a neutrino in order to...

I have been amateur reading about beta decay. The example given for electron capture was krypton-81 into bromine-81. Going from a noble gas to a halogen gives rise to a big change in chemical potential energy. How is this energy accounted for in the equations of the reactant particles and...

Hey everyone, I have a question about how "viable" the Quantum Anti-Zeno Effect (AZE) is at lowering decay rates in radioactive nuclei. We know that the AZE can, in fact, reduce the half life of radioactive isotopes, but there seems to be a barrier to that. AZE states that decay can be...

Homework Statement Consider the isobaric mass chain A=141. Using the NNDC website, determine what types of ground-state beta decays are possible for different elements within this chain (beta minus, beta plus, EC, etc.) as well as the nature (allowed, first-forbidden, etc.) Homework Equations...

Homework Statement A nucleus A decays into two nuclei B and C. The two nuclei have a combined kinetic energy of 581.9 MeV. What is the difference between the rest mass of the parent nucleus A and the combined rest mass of the two produced nuclei? Give your answer in atomic mass units u, with...

Hi there, I'm looking for some interesting activities regarding nuclear physics in high school. I already have: - building a cloud chamber with dry ice or peltier modules - simulating radioactive decay with dice - simulating Rutherford's experiment hitting with glass marbles a hidden target...

I know that Q value of a reaction is the difference between total initial mass-energy and total final mass-energy of all the products. Then shouldn't be this also the maximum kinetic energy and hence endpoint energy of an electron in beta decay. But what I have read endpoint energy ##E_0 = Q +...

Could I please check if my answers to the following three questions are correct? My answers are in bold. 1. How would you expect 39Ca to decay? a) β+ or electron capture (EC) b) Electron capture only c) β- d) α 2. How would you expect 39Ar to decay? a) β+ or electron capture (EC) b) Electron...

I thought of another question(s) :) does temperature affect the rate of the decay at all? Does temperature effect the energy of the decay; in that the energy of the electron anti neutrino would be higher?

I have heard that the probability of an unstable nucleus decaying is always constant. Is there any way to change this probability?

I would like to know if is safe to stay in Sendai (less than 100 km from Fukushima). I have read different information in internet but I think is better to ask a expert, I am not sure about the radiation since it seems is not stable, it could be between 0.4-0.6 msv if I understood, is that ok to...

Homework Statement A source having a half life of 5.27 years is calibrated and found to have an activity of 3.5*10^5 Bq.The uncertainty in the calibration is +- 2% Calculate the length of time in days after the calibration has been made for the stated activity to have a maximum possible error...

Hello Let's suppose a beta-decay. The mother nucleus is dM heavier than the daughter nucleus. What happen if the excitation energy does not match any combination of excited states in the daughter nucleus? Example: the daughter nucleus has 100keV of excitation energy, but the first exited...

Are there equations that detail the stability of nuclei against beta decay? On a related point, I'm familiar with the chart that shows all the isotopes and their half-lives (with a good chunk undergoing beta decay), but I was wondering if that can be derived from first principles, just using the...

Is it theoretically possible to stimulate a radioactive nucleus so that it decays on demand instead of randomly?Could this be used to accelerate decay of dangerous fission by-products?

Hi! I just keep having a hard time looking for the formula stating the relationship between half life, the initial number of unstable nuclei and the initial activity, can someone help me on that ? To be more specific, here is a problem which can be solved using that formula: "A substance has a...

Hi, I am struggling with a question where they want me to determine whether or not three different decay are allowed. From what I have understood all decays must follow a set of conservation law. These laws are: 1 Conservation of Baryon number 2 Conservation of Lepton number 3 Conservation of...

Homework Statement The formula being derived is N=No*e^k*t, from the equation Nn=No/2^n where No is the initial number of particles and the lowercase n in the second equation is the number of half lives. The n in Nn just indicates the number of particles after so many half lives. You might also...

Hello I was reading this post, https://www.physicsforums.com/threads/nuclear-decay-of-a-small-number-of-atoms-calculation.853664/ and I wander if the binomial distribution is still a good model if you have a small amount of nuclei, and in addition they can decay by different processes (each...

Homework Statement A stationary nucleus undergoes radioactive decay. A beta particle and a neutrino are detected leaving the nucleus. What is the recoil velocity of the remaining nucleus? If the recoil velocity measured is significantly different from the calculated velocity, what conclusion...

I came across a rather dubious question that a teacher had put in a power point. It said something like,"Given a sample of 100 atoms of isotope x, after one half life of the said isotope, how many atoms of the original isotope will be left?" My answer was that it was a trick question because...

Homework Statement The half life T½ of Carbon-14 is 5730 years. What is its decay constant? After what length of time will 35% of an initial sample of Carbon-14 remain? Homework Equations Decay constant λ= 0.693 / T½ Where N = amount of radioactive substance, N=N0e-λt The Attempt at a...

Homework Statement If a radioactive sample of 59Fe (t1/2= 44.496 d) has an activity of 1000 disintegrations per minute, what weight of 59Fe is present? Homework Equations

I'm sorry for posting this another thread, but I accidentally posted under to wrong forum initially and could not figure out how to delete it :-(1. Homework Statement Find the missing isotope: Iodine-127 (n, alpha) My answer is Sb- 122 but it was wrong. Also, how would I go about finding the...

Hi all, I have a question concerning the derivative of the formula of the number of nuclei. I hope I've posted this in the right section, I'm new here :P. Anyway, in the question, the given values are: At a certain time t, there is an amount of radioactive Br-82. The activity A is 7.4*1014 Bq...

Homework Statement (a) What processes changes atomic number by 1? What are the favourable conditions? How do you tell a neutrino is involved? How can we use this to understand the mass of this particle? (b) Use semi empirical mass formula to explain why odd-odd isobars are unlikely, while...

So I was reading this article about http://www.wired.com/2013/09/plutonium-238-problem/all/ and it got me thinking about possible substitutes. This is what I came up with. You make thin sheets of beryllium mixed with some kind of alpha particle emitter. You also make thin sheets of some...

Homework Statement (a) Find energy of incoming beam that creates highest cross section (b) What are the differences in the two reactions, using quark diagrams? (c) What would the peaks of the two reactions be like? Homework EquationsThe Attempt at a Solution Part(a) [/B] Cross section is...

Adopted from my lecture notes, found it a little fishy: Shouldn't ##\frac{dp}{dE} = \frac{E}{p}## given that ##p = \sqrt{E^2 - m^2}##. Then the relation should be instead: \frac{dp}{dE} = \frac{E}{p} = \frac{E}{\sqrt{E^2 - m^2}}

We consider the following beta decay: ^A_ZX \rightarrow ^A_{Z+1} Y + e^{-} + \nu_e The Fermi golden rule is given by: \Gamma = \frac{2\pi}{\hbar} |A_{fi}|^2 \frac{dN}{dE_f} Reaction amplitude is given by ##A_{fi} = G_F M_{nucl} ## while density of states is given by ##dN = \frac{4 \pi...

Homework Statement The isostopc abundances of a sample is U-235 and U-238 are 0.72 and 99.27 respectively; what is the age of the sample? (assume isotope abundance was equal when sample was formed) Homework Equations \lambda=\frac{ln2}{ t_{\frac{1}{2}}} The Attempt at a Solution for U-238...

For example tritium has a half life of of 12.3 years. So if you had 2 atoms of tritium then after 12.3 year you would expect to have 1 atom of tritium and 1 atom of h-3. My question is, is it possible that tritium could decay in 1 second? Or how about 1 eon? I know its not probable but is it...

The answer is not provided by AAPT. Homework Statement A mixture of ^{32}P and ^{35}S (two beta emitters widely used in biochemical research) is placed next to a detector and allowed to decay, resulting in the data (attached) below. The detector has equal sensitivity to the beta particles...

Homework Statement If all of the energy from decay of the 40-K in one banana could be captured and converted into electrical energy, how many bananas would be needed to power a 100 W light bulb? There is 358 mg potassium-K per 100 grams of banana half life of potassium-40 is...

Hello everybody, I am a first year and I have one more question. To what degree do electron contribute to nuclear decay? (Do electron which can 'spend' some time in the nucleus cause bigger decay?) Thanks in advance :)

Homework Statement Radioactive nuclei A are produced at a rate R per second in a nuclear reactor. They decay with probability λ per second. (Qu 1-2 involving deriving the rate of change and number particles at any given time, I've done this). 3) Show the activity tends to R, a constant, as...

Hello, Would all radioactive decay lead to a daughter nuclide in a "nuclear excited" state, and if so, would this indicate that gamma rays are emitted in order for the nuclear ground/stable state to be reached after any decay? Also, if nuclear decay occurs b/c of the imbalance of...

Nuclear Decay question without knowing N0 or N ?? Homework Statement Ok so what I have an Am sample which emits alpha particles at a rate of 70Bq in 1997 and asks for the activity 8 years later (the half life of Am being 432.2 years) I found this to be 69.108 Bq, first of all does this sound...

Is it possible, in theory, that a radioisotope undergoing nuclear decay (eg. alpha particle emission) can be modeled so as to determine the origin and/or direction of the emitted particle? For instance, perhaps one could model nucleon interactions deterministically and observe that when the...

I think I understand the basics of the SM and know that the W and Z bosons are the mediators of the Weak Force. I also understand from chem the basics about nuclear stability (ratio of protons to neutrons, valley of stability/nuclear binding energy, etc.). What I'd like to know is what the...