Questions tagged [plasma-physics]
Questions about the 4th state of matter, namely a mixture of particles like ions, free electrons and usually also neutral atoms or molecules.
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Could a red dwarf be "deionized"?
Even the smallest red dwarf stars have amazing flares. But the photosphere temperature can be as low as 2700K, which (I think) is too cool to ionize hydrogen. Even the sun at 5800K is cool enough that ...
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What is value of charge by mass ratio (q/m) for a spherical micro charged particle with surface potential 6 volts in S.I units and in e/amu units?
In Liu and Ip (2014),The Astrophysical Journal, 786:34 (8pp), the value of q/m is derived as follows :
"for a dust grain with radius 'a', from $\phi = \frac{4\pi q}{\varepsilon_0 a}$ we have $\...
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Would impacting plasma clouds destroy electronics on Earth or make them only temporarily inactive?
We read that solar flares have increased again recently. At the same time, it is always reported that the plasma clouds hitting the Earth would, under certain conditions, disable all electronics on ...
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Do whirlpools of turbulence exist in stars just like the whirlpools that exist in water?
Is there turbulence in the hot plasma and gas of stars that is mathematically the same as whirlpools in water?
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Numerical Programming using ODEINT takes more than 17 minutes
I am trying to track the trajectories of a charged particles under the influence of Gravitational and Electromagnetic effect. Computing for time points, t0=0second -tf= (36002430)sec with stepsize 0....
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How to build functional sunspot model on the ground with high-power plasma burners in the strong magnetic field as conference paper?
I need to build functional sunspot model on the ground with high-power plasma burners in the strong magnetic field as conference paper.
What I get is light-weight plasma, as exactly plasma is.
But I ...
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Is the Solar core hard?
This may seem like a weird question, but something got me thinking about it just recently.
The Sun's core is composed of mainly hydrogen and helium, and is present in the form of a extremely hot ...
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Question about plasma parameter
As we know, the deflection angle in strongly ionized plasma can be written as $$ \tan \frac{\theta}{2} = \frac{l_0}{l}, $$
where $\theta$ is the deflection angle, $l_0$ is the impact parameter when $\...
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What is the main difference between cyclotron, synchrotron, and gyrosynchrotron radiation?
How are these various types of radiation generated? What is the main difference between them? Can someone suggest a book related to these radiations?
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Do the newly-created deuterons in our Sun release any photons? In addition to a positron and an electron neutrino?
Perhaps this is a nuclear physics question, but....
When two colliding protons deep inside our Sun finally turn into a deuterium nucleus or deutron (after approximately ten octillion chances, on ...
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Density of Plasma in Solar Corona
The Sun's atmosphere, also known as the solar corona, is known to be extremely hot, much hotter than the Sun's surface. What is the plasma density in the solar corona?
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How is the H II 'region' directly detectable? By Compton or Thomson free-particle scattering? At what wavelengths?
The Wikipedia page on H II regions says that they are 'indirectly' detectable by the detection of doubly-ionized oxygen atoms mixed in.... (I am presuming atoms, not diatomic molecules...)
But are ...
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Are plasma nuclei detectable? By the occasional emission of gamma rays, perhaps?
As stated above....
How often do nuclei stripped bare emit radiation?
Can nuclei be identified by the wavelengths or amplitudes of gamma rays they emit? How about isotopes?
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Is it possible to observe Lyman-continuum emission from extragalactic objects?
Lyman-continuum (LyC) emission is everything blueward of 912 Angstroms (so it includes extreme UV photons, X-rays and gamma rays). There are many low-redshift astrophysical plasmas such as the diffuse ...
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Is **Voyager I’s** reduced data transmission rate as described in [this article][1] because of the distance or because its transmitter getting slower? [closed]
Is Voyager I’s reduced data transmission rate as described in this article because of the distance or because its transmitter getting older & slower?
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Help understanding ring diagram analysis used in helioseismology
I need help understanding something. In global helioseismology we study the modes directly (stationary waves characterized by 3 integers numbers: $n$, $l$ and $m$). As the angular degree $l$ becomes ...
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Do free protons and neutrons absorb much radiation? To affect astronomers' observations? If so, at what wavelength(s)?
In a plasma, or wherever, do the completely ionized nuclei commonly absorb much EM radiation? Or any free neutrons or protons? Can astronomers detect this? Enough so that astronomers take it into ...
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How to determine arrival time delay given dispersion measure?
In an online textbook, the following formula is given to calculate the arrival time delay between two frequencies, $v_1, v_2$ in a dispersed radio pulse:
$$t_1 - t_2 = 4.15 \cdot DM [(v_1/\text{GHz})^{...
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Blue color of ion (plasma) comet tails
What exactly is the cause of blue light of ion (plasma) tails of comets? Somewhere I have read that the source of blue light are CO+ ions which has just acquired the missing electron and became ...
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Energy of a charged particle in the magnetosphere
I asked this question on physics.stackexchange, but as it is a space/magnetosphere question maybe someone here can help me out:
Taking the earth as an idealized dipole and the E field from the sun ...
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Is it dark inside the Sun?
This might sound like a strange question, but something got me thinking about it recently.
The opacity of plasma in stellar interiors can get quite high, making for shorter free-paths for photons. In ...
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Has the plasma amplification of electromagnetic waves in solar type-III bursts (or otherwise in stars) been explored further?
This answer to the SciFi SE question In the novel The Three-Body Problem, does the Sun's amplification of radio transmissions have a scientific basis? cites a 1995 paper published in Chinese Astronomy ...
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Voyager 1 and 2 detected a 20-fold increase in plasma density, significantly different refractive index?
As reported by Nature.com, Voyager 1 and 2 detected a 20-fold increase in plasma density going from the heliosphere out to interstellar space. Does that 20-fold difference in density imply a ...
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If interstellar medium was dense plasma and light slowed down, would things appear to move slower far away?
Voyager 2 recently left the solar system and registered an increase in plasma density. If light moved slower in this dense plasma, would it appear like events in other solar systems played out slower ...
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What is the "radiation sound speed" inside an accretion column?
I was trying to read "A New Two-fluid Radiation-hydrodynamical Model for X-Ray Pulsar Accretion Columns" and its follow-up paper both by West et al. and came across a quantity called "radiation sound ...
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Does plasma recombination in the solar wind happen to any significant or measurable degree?
Comments below this answer to Why does the Solar Wind consist of charged particles? have led me to ask the following:
Question: Does plasma recombination in the solar wind happen to any significant ...
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How far can you see in solar plasma at just under 1 solar radius?
I was trying to compose an answer to this question here, about touching the surface of a star, and I was going to mention that the popular depiction of the sun's surface as 'basically lava' (as ...
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Will the Sun's solar wind push a permanent magnet out of our solar system?
If you were place a strong permanent magnet into the solar wind, like a 1 inch cube neodymium magnet, would the charged particles of the solar wind colliding with the magnet's magnetic field push the ...
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Just after the Big Bang, was the space, in its entirety, filled with Hot gas?
After the Big bang occurred, was the space filled with hot gas totally?
If there's any problem in my question please inform me. Thanks!
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Could there be massive charged “rivers” in interstellar space?
Some suggest that there might be currents of charged particles moving at 0.98c in interstellar space. Since this is tainted by association with the crack “Electric Universe” cosmology, my first ...
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Are sunspots vertically displaced from the surrounding photospheric plasma?
While reading a paper on the helioseismology of sunspots (Cameron, et al.), very brief reference is made to the "vertical displacement of a blob of plasma." This caused me to wonder if the emissive ...
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Do some ELF (Extremely low frequency) radio waves pass the atmosphere
...reach Earth surface and then are reflected passing the atmosphere again to reach outer space? And once in outer space can they travel indefinetely in it or the interplabetary plasma would stop them?...
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What is the temperature of the solar atmosphere (the corona) and how is it measured?
The temperature of the Sun's atmosphere, also referred to as the solar corona, is known to be hot even hotter than the Sun's surface. What is its temperature and how is it measured? How does it ...
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Population of excited H levels in a Strömgren Sphere
In chapter 2.2 of Astrophysics of Gaseous Nebulae and AGN Ostriker and Ferland claim that, as far as ionization is concerned, one can assume all atoms to be in the ground state in a Strömgren Sphere ...
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What triggers solar flares?
The sun is a big ball of hot plasma which contains free electrons. However, how does the absence of metallic elements in the sun generate the magnetic field to orchestrate these free electrons to ...
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Nuetrino interaction with plasma and electromagnetism [closed]
Following question enter link description here
After watching the Thunderbolt Project on Youtube I have a very very very fresh perspective on the universe - the electric universe. From the electric ...
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On analogies between gas and stellar systems
Analogies between (typically) ideal gas and stellar systems are not only intuitively valid to some extent, but have been established and used in the studies of stellar clusters and galactic systems, ...
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Stars at near break-up rotation rates
Accretion discs are ubiquitous in astrophisics. As a direct corollary, they are important for the following question.
Consider the following model, representing one of the most simple models for ...
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Does the Sun rotate?
The planets rotate as an after effect of their creation, the dust clouds that compressed span as they did so and the inertia has kept it rotating ever since.
It's fairly easy to prove that planetary ...
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