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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Is there such physical cryptography? [closed]
In chemistry and physics, is there some sort of science that studies cryptography physically?
Generally, cryptography exists in the world of computer science, logical cryptography or simply ...
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Could an electron wavefunction wrap multiple times around its orbit?
In the Bohr model a whole number of electron de Broglie waves with $\lambda=h/mv$ fit around an orbit with radius $r$ so that we have:
$$2\pi r=n\lambda.$$
But could the electron waves wrap around the ...
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Superposition of energy levels
When thinking about a "random" atom in space (say a Hydrogen atom), should I assume that the electron is in a ground state (or any particular excited eigenstate) or is it in a superposition ...
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Does electron have a temperature in the atom?
Please correct me if I am wrong. Electron is fundamental and is zero dimensional (probably made up of strings). Electron is bound to the nucleus. Electron in an atom has velocity and position which ...
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Does population inversion in the Dicke model result in the production of a coherent state of the cavity field?
The Dicke model describes the quantum dynamics of $N$ identical two level atoms (with energy seperation $\hbar\omega_{0}$ between the ground and excited energy levels $\{|g\rangle,|e\rangle\}$) each ...
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Electronic configuration and symmetry labels of 3d$^7$ ions
In 3d$^7$ ions, e.g. Co$^{2+}$, the ground state is $^4$F, and it contains different levels due to the crystal field, such as $^4T_{1g}$, $^4T_{2g}$ and $^4A_{2g}$. Can anyone tell me what exactly ...
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Compton scattering problem with photon energy equal to electron rest energy [closed]
A photon whose energy equals the rest energy of the electron undergoes a Compton collision with an electron initially at rest: What sort of a photon is it? i.e. X-ray, visible, etc? If the electron ...
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Excitation and decay of electronic states to dark states
I am interested in modeling the populations of low-lying, long-lived "dark" electronic states after excitation of an atom in the ground state with a laser. Using just a regular rate equation ...
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Wigner-Weisskopf method for Time Varying Perturbation
In Time Dependent Perturbation Theory for coupling of a discrete state to a continuum you use the Wigner-Weisskopf method to describe how the initial state gets depopulated and final states populated ...
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Complex expression involving pochammer symbols and sums arising from laguerre integral, can it be simplified? [duplicate]
I am working on simplifying a complex expression that arises from a quantum mechanics problem involving matrix elements. The expression is given by an integral involving Laguerre polynomials, which I ...
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Time of relativistic scattering
Consider a scattering collision between a relativistic electron and a Hydrogen atom, which is assumed to be in the ground state. Assume that the electron velocity is comparable to the speed of light $...
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Why can we cool one species Fermionic gas in evaporative cooling?
I met a problem in the evaporative cooling of Fermions. If I want to cool Fermionic gas to a very low temperature, I need to let s-wave scattering happen in the evaporative cooling process.
However, ...
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Why doesn't the total energy in Bohr's model of the atom include the energy in the magnetic field of the electron?
When the electron "jumps" from a more energetic state to a less energetic state, its orbital speed increases since its kinetic energy equals $\frac{kZe^2}{2r}$ (where $k$ is Coulomb's ...
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$ \hbar^2$ Correction to the Bohr-Sommerfeld Quantization Condition
We can get the Bohr-Sommerfeld quantization from the WKB method as answered. Since we use approximation, there should be an error in the system, I know this is not right all the time; in some ...
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How to calculate the $d$ orbital energy from Atomic Spectra Database?
I am struggling to understand how to calculate the $d$ orbital energy of the Fe atom. I tried to search the $\text{Fe I}$ in the Atomic Spectra Database, so I thought I could use the energy difference ...
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Casimir effect and lambshift, uncontroversial evidence of the zero point field? (SED)
"By far the most accepted evidence of the reality of the zpf is the Casimir effect, that is, the force between two parallel neutral metallic plates resulting from the modification of the field by ...
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How to find the standard atomic orbital energy data?
I found a website that provides the $d$ orbital energy of atoms. The data were found using Photoelectron Spectroscopy, which measures the energy needed to ionize electrons from atoms in the gas phase.
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Why would a hydrogen atom form if proton and electron are left to attract each other, when they are very near? [closed]
In this question the OP asked, if electron and proton ,which are very near to each other,are left to attract in a straight line then what will happen? The answer was that a Hydrogen atom will form.
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Why are electron orbitals shaped how they are?
I'm new to quantum physics, but as far as I've understood, electron orbitals are defined as the region where an electron has a 90% probability to be. Unless I'm wrong, every point has some probability ...
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Strange fine structure splitting of the two-body Dirac equation
This question is a follow-up of the discussion about one of my answers.
Marsch proposed a two-body Dirac equation for hydrogen in order to treat the proton recoil effects in a non-perturbative way (...
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Youtube video claims 2023 physics Nobel prize winners proved Heisenberg wrong
This video claims (scroll to 11:22 frame), that inventors/improvers of a unique attosecond pulse generation which enables us to monitor atom dynamics proved that Heisenberg was wrong (citation from ...
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Physcial interpretation of term neglected in Rotating Wave Approximation
Consider an atom as a two-level system $|1\rangle, |2\rangle$ with energy separation $\hbar \omega_0$, which is interacting with a classical electric field $\vec{E}=\vec{E}_0 \cos(\omega t)$. This ...
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Bohr model of the atom
According the classical physics, the electron should radiate energy and fall to the nucleus in a short period of time. However, this was not the case. Hence, Bohr proposed his theory, suggesting that ...
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Why is a singlet state potential greater than triplet state potential in the Feshbach resonance experiment?
I googled the Feshbach resonance in the Wikipedia and I have some problems. In German Wikipedia, they consider Li-6 molecule as an example.
For these two different spin configurations(singlet and ...
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Atom Interferometer Contrast
I have made a simulation of a Raman beam based atom interferometer in a Mach-Zehnder configuration. In this way, the electronic state of the atom changes as well as the momentum when diffraction by ...
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Mass to energy in nuclear reaction
According to my understanding we get a lot of energy during nuclear reaction because mass transforms to energy. According to picture below total mass remains the same after reaction.
Is the picture ...
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How long does it take for a $\rm CO_2$ molecule close to the surface of the Earth to reemit an absorbed terrestial infrared quant after absorption?
In the theory of climate change a special position is reserved for $\rm CO_2$. In this theory $\rm CO_2$ molecules are absorbing infrared quants emitted by the surface of the Earth. These quants are ...
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Why sodium ion is able to atract negative charges? [closed]
Why is the sodium ion able to attract negative charges? even though it has 1 excess proton, its electrosphere is further away than the nucleus, wouldn't it be possible to counterbalance the effect of ...
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Refraction of sound atomic level
how the refraction of sound and the change in the angle of propagation can be explained at the atomic level, why the direction of propagation of molecules changes in different media?
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How is the proton accounted for in the relativistic solution of the hydrogen atom?
In the non-relativistic limit, the Schrodinger equation for the hydrogen atom can be solved using reduced mass techniques to account for the motion of both the electron and proton.
I am wondering if a ...
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Dependency of Stark effect on Quantum numbers
I have read many sources which tell me that the Stark and Zeeman effects, which Bohr's theory had trouble explaining, were explained by the introduction of the magnetic quantum number. But doesn't ...
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Obtaining Current From Quantum State of 3d, assumed hydrogen atom
So I've been banging my head against this problem for a while and I genuinely have no clue how my answer is differing than the one provided to me and while I'm not usually the type to ask such a thing,...
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How to explain this observation in Franck-Hertz experiment?
We did the Franck-Hertz experiment in our physics lab. The setup was like this
We fixed the value of $V_{G_{1}K}$ and varied the values of $V_{G_{2}K}$ and got the curve for the electron current vs ...
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Do attosecond lasers allow us to further constrain the location of electrons within the established probability clouds, via time?
It has only been within the last few years that I learned the atomic model I grew up with (the Bohr model) was wrong, and that I should instead be thinking about electron orbitals as a cloud of ...
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Velocity of de-Broglie Wave
I have been trying to figure out the solution to this problem of finding the "velocity" of de-Broglie's wave. I have tried to see answers from countless sources but none of them helped. My ...
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ESR Half Field Transition
I am studying ESR with Atherton.
While reading the book, I found something weird (at least to me). Can anyone help me with this?
What I know is that $M_S = 2$ transitions can occur because at low ...
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What is the importance of excited states in the emission of gamma radiation during alpha decay?
Let's suppose that during a hypothetical alpha decay of a nucleus X, has two excited states (such as 2.3 mEV and 0.9 mEV) are respectively fed.
The question arises here: what would would be the energy ...
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Can an atom absorb a photon, yet finds its total kinetic energy decreased?
Let's assume an atom consists of the nucleus and electrons as point particles. Take the inertial frame to be that of the fixed laboratory. Its total energy consists of the total kinetic and potential ...
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Books on Hyperfine Splitting (Theoretical Physics)
Do you have any good recommendations on books (theoretical physics) about hyperfine splitting?
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When a laser pulse rate is stated, does that include the time that it is off? If pulse rate is 1,000 per second, is it on for half a millisecond?
Sorry if this seems a stupid question to some, but I am having trouble finding a consistent answer....
The European XFEL hard X-ray headline proudly states that it is currently the fastest of its kind ...
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2023 physics Nobel prize - why does it matter? [duplicate]
From the citation:
In 1987, Anne L’Huillier discovered that many different overtones of light arose when she transmitted infrared laser light through a noble gas. Each overtone is a light wave with a ...
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What is an "attosecond pulse", and what can you use it for?
The 2023 Nobel Prize in Physics was announced today, and it was awarded to Pierre Agostini, Ferenc Krausz and Anne L’Huillier, for
“experimental methods that generate attosecond pulses of light for ...
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Calculating the recoil mass of an atom after absorption of a photon [duplicate]
I'm solving a problem 4.11 in <Introducing Einstein's Relativity, Ray D'Inverno>. The problem states as follows:
An atom of rest mass $m_0$ is at rest in a laboratory and absorbs a photon of ...
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How do contact forces change with distance?
Typically, two bodies don't exert a force on each other when separated, but if they go in contact with each other, that is, get sufficiently close, contact forces arise. Consider the case I press my ...
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How does Einstein's paper on Brownian motion actually prove atoms exist?
Reading through Einstein's Brownian motion paper "On the Movement of Small Particles Suspended in Stationary Liquids Required by the Molecular-Kinetic Theory of Heat", it seems the final ...
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K-Shell, Low-Energetic Photons & Photoelectric effect
At low photon energies, the probability of the photoelectric effect to occur increases, but the probability of the photoelectric effect to happen also increases when going towards most inner shells ...
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Construction of an $N$ electron orbital and spin state
Consider a system of $N$ electrons. Their Hilbert space is the antisymmetric subspace of $\mathcal H = \mathcal H_e^{\otimes N}$, where $\mathcal H_e \cong L^2(\mathbb R^3)\otimes \mathbb C^2$ is the ...
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Explanation of the Rydberg interaction hamiltonian and its controllability
I have been reading about Rydberg atoms and their interactions and the possibility of quantum computation using this platform and I have come across this-
The quantum dynamics of this system is ...
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Matter wave of macroscopic objects
By De-Broglie's hypothesis it can be said that every matter has a dual nature associated with it, and the relationship being:
$$\lambda = \frac{h}{p}$$
Now by applying this relation on a macroscopic ...
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Thomson Scattering when low intensity light meets an orbital electron
Can you explain to me the reason why Thomson Scattering can not explain what happens when light meets an electron at low intensity, and what does that have to do with light being a wave or particle or ...
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