All Questions
Tagged with radiation quantum-mechanics
68
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If a proton transforms into a neutron by releasing a positron why should this process create more mass? [duplicate]
If waves can interfere and thats why cancel out or add up why we cannot think the same about the natterial feature called mass as in this explained example in the title of this posted question??Thanks ...
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Is the generation of NMR signal due to spontaneous emission?
The usual description of how NMR signal is generated is that the sample has some equilibrium magnetisation along the $z$ axis, this is then flipped into the $x$-$y$ plane by a 90° pulse and there it ...
- 689
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Self-interference of nuclear decay
Consider a stationary atom undergoing radioactive decay. The probability density function for decaying at time $t$ is given by an exponential distribution:
$$p(t)=\lambda e^{-\lambda x}$$
When ...
- 1,440
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If the time at which a single atom decays is random, why do groups of atoms behave in predictable ways? [duplicate]
Why do groups of atoms decay at predictable rates even though a single atom’s decay point is completely unpredictable? I’m having trouble wrapping my head around this.
From my reading, it seems that ...
user353810
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Difference between endpoints and kinetic energy in a beta minus decay
I want to understand the difference between the Q value and Endpoint energy and Kinetic energy of a beta minus decay.
I understood that the Q value is the overall energy of the reaction given by
Q ...
- 29
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72
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Jumps between energy states of harmonic oscillators
I have recently read that in perfect harmonic oscillators to go up or down in energy state you have to go, using the simile of a staircase, step by step, emitting or absorbing a photon of energy $E=\...
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Why doesn't KE of annihilation electrons necessarily have to be equal to each other?
We know that when a high energy gamma ray(E >= 1022 keV because the total energy of 1 electron at rest and 1 positron at rest is 511 keV) passes near a high Z(atomic weight) atomic nucleus ...
- 151
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2
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Averaging transition rate for absorption in dipole approximation for unpolarised radiation
The transition rate corresponding to the first-order probability of absorption is given in the dipole approximation as
$$W_{ba}=\frac{dP_{ba}^{(1)}}{dt}=\frac{\pi I(\omega_{ba})}{\hbar^2 c \...
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1
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53
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Harmonic perturbation in interaction of radiation with quantum system; making sense of approximation of the integral
In the chapter "The interaction of quantum systems with radiation" (Quantum physics book by Bransden and Joachain, 2nd edition) section 11.2 "Perturbation Theory for harmonic ...
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2
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Spin of electron and photon emitted
How does the spin state of the electron affect the polarisation of the light emitted?
I am looking for a description in a detailed mathematical aspect, any suggestions on books ?
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Is radioactive decay deterministic? [duplicate]
Suppose you know at time $t$ that there is some atomic nucleus that radioactively decays.
If you were to magically roll back the universe to the exact same state and let it continue as per usual ...
- 185
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131
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Are quantum events such as decay, emission, absorption and tunneling truly instantaneous or is there some small time period? [duplicate]
Are quantum events such as decay, emission, absorption and tunneling truly instantaneous or is there some small time period?
Assuming there is an underlying cause for a quantum event it seems to me ...
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1
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146
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Tunnelling of alpha particles - explanation
As it is now known because of Gamow, how alpha decay occurs. We have taught this theory in our class in last week. There we have been introduced with a strange phenomenon happening because of which ...
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Can a nuclear electromagnetic transition rate be affected by the electron configuration (e.g. bare nucleus v neutral atom)? Any experimental examples?
When an atomic nucleus undergoes a transition and emits a gamma ray, the wave function of the nucleus changes, which can result in a slight redistribution in charge.
Some electron orbitals have a ...
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Transfer of energy from radiated to conducted
Can a CO$_2$ molecule in the atmosphere that has been heated by the earth's radiation, transfer that energy to one of the many O$_2$ or N$_2$ molecules nearby? If so, what is the mechanism?
