Questions tagged [atomic-physics]
Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. It is primarily concerned with the arrangement of electrons around the nucleus and the processes by which these arrangements change. This includes ions as well as neutral atoms and, unless otherwise stated, for the purposes of this discussion it should be assumed that the term atom includes ions.
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When does electrostatic effect failed and needs quantum mechanics?
This is a question from 2022 AP physics 2 FRQ, I am not here to ask how to solve the question, but I am curious about the assumption made by this question. It says that electrostatic force is the ...
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Calculation K- and L- absorption edge of Yttrium, why do the values deviate significantly from the literature values? Moseley's law
I want to calculate the K- and L- absorption edge of Yttrium
I am using Moseley's law:
$$E=(Z - \sigma)^2 \cdot 13.6\text{eV} \left( \frac{1}{n_i^2} - \frac{1}{n_f^2} \right)$$
So, in this case:
$$E=(...
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How can any object except Plasma emit white light or be a blackbody--it seems contradictory?
How can any physical object absorb and emit white light when all objects are made from atoms and molecules, each of which has its own absorption/emissions spectrum that acts as it's signature “...
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Energy and momentum conservation for photon absorption [duplicate]
As an undergrad physics student, I am pondering on this question.
If an (2 level) atom absorbs a single resonant photon, the energy of electronic state increases by $\hbar \omega$. At the same time ...
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Hund's rules in Helium level scheme
If I am not wrong, Hund's rules state that:
I) The highest $2S+1$ has the lowest energy.
II) For a given $S$, the lowest $L$ has the highest energy.
However, I have found in various textbooks the ...
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Energy eigenvalue of hydrogen-like atoms using Laplace-Runge-Lenz vector
I have a basic question about a few calculations involving the quantum mechanical Laplace-Runge-Lenz vector.
In classical mechanics there is the Laplace-Runge-Lenz vector, which for a hydrogen-like ...
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Continued calibration of atomic clocks
First off I am not well versed in physics, but as I understand things the second is defined by the ceasium fountain clock which is calibrated as follows How was the first atomic clock calibrated?. Now ...
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Will an electron release energy when it is added into an atom for which electron affinity value is negative (endothermic)?
According to my understanding, when an electron is added into an atom, it emits energy in the form of photons because it is a form of de-excitation or relaxation. This is when electron affinity will ...
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Do lasers with optical isolator or synchrotron radiation sources allow for Rabi cycles?
In Rabi cycle two-level system cyclically transitions between ground and excited state - bringing question where their energy difference goes during these transitions?
For transition from ground to ...
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Extracting electron wave functions from experiments
In nuclear and nucleon physics it’s quite standard to extract electromagnetic form factors – which are the Fourier transforms of charge and current distributions – from elastic electron-nucleon or ...
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In layman’s language what is the difference between stopping potential and work function?
In layman’s language what is the difference between stopping potential and work function? It feels like both the things mean the same thing, if I am wrong please explain the things to me.
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X-ray absorption edge, accurate theoretical predition possible?
It is well known that in X-ray absorption spectroscopy, the absorption spectrum shows discontinuities at some critical frequencies.
Is it possible to predict locations of these jumps theoretically? I ...
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Surely $\rm CO_2$ reflects incoming solar infrared radiation?
Is the greenhouse effect not cancelled out by the $\rm CO_2$ in the atmosphere reflecting solar infrared radiation back into space? It seems logical to me that, if $\rm CO_2$ reflects infrared shifted ...
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Is the total angular momentum $J$ a good quantum number for the Breit intereaction?
I am reformulating this question because the previous one was closed to the to the claim that is a homework question.
According to Wikipedia the Breit operator is given by
$$
\hat{B}_{i j}=-\frac{1}{2 ...
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What’s the heaviest possible atomic nucleus?
What’s the heaviest theoretically possible atomic nucleus (highest element number) that can possibly be said to “exist”, such that if one single additional nucleon were added it would collapse into a ...
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