Questions tagged [cosmic-rays]

Cosmic rays are highly energetic, charged particles (protons, alphas, electrons, etc, with energies ranging from $\sim10^9\text{ eV}$ to at least $10^{20}\text{ eV}$) from various galactic and extragalactic sources, that often interact with our atmosphere. Consider adding other tags to specify the origin you're interested in (i.e., solar or galactic).

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How much energy does a cosmic ray lose before it hits a detector?

The origin of extremely high energy cosmic rays is still unclear, by my understanding. But say that they are produced by whatever local source does it: how much energy is lost to environmental effects ...
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Solar modulation of cosmic rays

Whilst studying cosmic rays (CRs) and the influence of the sun on the intensity of the CRs, I read that solar modulation mainly affects low-energy CR-particles. Could someone maybe explain to me why ...
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Source spectral index

Whilst studying the propagation of cosmic rays (CRs) through our galaxy, I was comparing simulated data to data measured by the Alpha Magnetic Spectrometer 02. I am studying the proton flux within CRs ...
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On "cosmic flux" units

I've trouble understanding the following graph, taken from Wikipedia: It's supposed to show the cosmic ray flux vs particle energy. I've never seen a "flux" written in these units... Why ${...
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Are there any plans for cosmic ray detectors as part of the new ARTEMIS program?

NASA's new Artemis program involves building several temporary waypoints around and on the moon. One of the side-bonuses for scientists is that this has opened a few new funding avenues for studying ...
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How are the other components related?

Often, the tensor of diffusion of cosmic rays in the inner heliosphere is given in terms of $k_{\parallel}$ and $k_\perp$, the coefficients of diffusion along and perpendicular to the magnetic field. ...
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What energy range is considered as a "high-energy" or "low energy" cosmic ray?

I have been studying cosmic ray muons lately, and I'm having trouble with making sense of all the eV values. What is the approxamate range (in eV) for "high-energy" and "low energy"...
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What is wrong with my cloud chamber? [closed]

Ive been trying to make a cloud chamber for a few days. I seem to have gotten most of the way there, but cant quite see any tracks, only mist. Im using isopropanol with cooling from salted water ice ...
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Why is interstellar cosmic radiation more energetic than radiation from our sun?

I just watched an interesting minidoc about cosmic radiation. The video, and other resources I've read afterward, explains that the most energetic cosmic radiation comes from supernovae and black ...
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Why is space radiation mainly positively charged? Where are all the electrons?

I've heard that space radiation is mainly, overwhelmingly positively charged. Wikipedia (Cosmic ray - Composition) says ...about 99% are the bare nuclei of well-known atoms (stripped of their ...
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Measure cosmic ray pions and protons below surface of the Earth?

In my particle physics lecture, the prof asserted that apparently cosmic ray muons can still be measured 1km below the surface of the earth (e.g. in a mine). This led me to ask the following two ...
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What is the acceleration rate of a neutrino? [closed]

I understand that photons do not have acceleration because they are massless. But what about neutrinos, which have been proven to have mass due to oscillation? Let's assume a typical Solar neutrino ...
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Did Victor Hess discover cosmic rays directly, or muons with his gold-leaf electroscope?

Most histories just mention cosmic rays themselves, but I also read that cosmic rays themselves rarely make it far into Earth's atmosphere, and it is usually muons, (or tauons or electrons) detected ...
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How to check the particle rate of $1\ m^{-2}.s^{-1}$ at an energy of $10^{12}\ TeV$ from the "Swordy plot"? [duplicate]

On this web page, we see the so-called "swordy plot" https://www.quantamagazine.org/ultrahigh-energy-cosmic-rays-traced-to-hotspot-20150514/ At an energy of $10^{12}\ eV=1\ TeV$, we read ...
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What is the current status or resolution of Greisen–Zatsepin–Kuzmin (GZK) cosmic-ray paradox?

The Greisen–Zatsepin–Kuzmin limit (GZK limit) is a theoretical upper limit on the energy of cosmic ray protons traveling from other galaxies through the intergalactic medium to our galaxy. A number of ...
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What happens to extra-galactic rays when they arrive at the solar system?

Quazars send baryons from other galaxies towards us which are deflected from by the local magnetosphere. The early solar system probably picked up many millions of extragalactic cosmic rays for every ...
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How do you convert between different units of particle flux?

Charts of particle flux tend to show the flux rate in units of particles per metre squared per second per steradian per MeV. I don't understand what the "per MeV" is referring to. How do I ...
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What happens when chemical elements are struck by cosmic rays?

When struck by cosmic rays, chemical elements in soils and rocks emit uniquely identifiable signatures of energy in the form of gamma rays. These data can help scientists look for geologically ...
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Radiation and windows for building of a great project in a low Earth orbit: reference request or exercise as a ficticious need to build it

I know about the existence of certain windows for which it is more suitable to launch a probe for the exploration of a cellestial body in our Solar System (see the Wikipedia Launch window). I wondered ...
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Could A Stray Radioactive Particle Collide With an Atom in a Human, Causing a Cascade?

I'm not thinking of even particles from a nuclear power-plant or man-made event. If a high-velocity highly-interacting particle made it through all the natural protections that keep life in a non-...
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Why is the GZK cutoff at such high energies?

Why is the GZK cutoff at such high energies? The threshold energy for Compton scattering is 0.511 MeV. But the inverse Compton scattering has a very high energy threshold. For example in ...
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The net charge of Earth

Shouldn't the earth have an over all small positive net charge? Cosmic rays in the form of light or high energy particles can ionize atoms, when that happens the electron and the positive ion recoils ...
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How much higher is muon flux at Earth's poles?

https://futurism.com/make-a-cosmic-ray-detector-at-home-and-test-relativity-2 This article states that the Earth's magnetic field funnels incoming muons towards the magnetic poles. Quantitatively, ...
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Why don't we see/feel charged particles, penetrating our brains/retina?

If we see tracks in bubble or Wilson chamber, it means that particles are everywhere and can leave tracks in gases and liquids. They can also penetrate concrete of the building levels in the lab. So ...
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Energy distribution of incoming muons from cosmic rays

I believe there has been research done which provides data on the kinetic energies of muons which result from incoming cosmic rays. I'm looking for a graph of counts (vertical axis) vs. kinetic energy ...
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Shouldn't cosmic rays slow down Earth's movement around the Sun?

Maybe a dumb question. Are cosmic rays slowing down earth's (or any planets) movement around the sun? To me it sounds like an analogy of moving a mass through air and being slowed down by the impact ...
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Why the geomagnetic field become stronger when solar wind is stronger?

The following description is from the webpage of Niels Bohr Institue's Former Centre for Ice and Climate The Earth reacts to the solar wind by increasing the strength of the shielding magnetic ...
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What affects the propagation of secondary cosmic rays?

Primary cosmic rays produce, upon entering the Earth's atmosphere, a whole load of secondary particles. These primary particles are necessarily stable particles such as protons, electrons, and ...
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Do space-borne cosmic ray experiments publish all-particle spectra?

I was trying to gather data to produce my own cosmic ray (CR) spectrum plot. I have relied on this very useful French database collecting past space-based CR measurements. If I try to insert the ...
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Does an atom or proton (cosmic ray) get stretched when traveling through expanding space?

I have read this question: Why does space expansion not expand matter? I do understand that matter inside galaxies will not get stretched because inside galaxies, gravity dominates over dark energy. ...
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Galactic or Extra-galactic Cosmic Rays?

If we want to show whether or not a specific Cosmic Ray particle is confined to our galaxy we must use the Larmor radius (relativistic version), $$r = \gamma \, \frac{ m c}{q B}$$ Considering a $10^...
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What exactly is delta-14C and why are there periodic plateaus in the delta-14C curve?

I downloaded the IntCal13, IntCal09, and IntCal04 datasets (parent site), and when I plotted the last 24k years was surprised to see a plateau or even reversal appear every ~5300 years. Apparently we ...
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What is the difference between an interaction and a decay in particle physics?

While studying secondary cosmic rays, I have encountered sentences like: Charged pions and kaons can either initiate further interactions or decay. or Because of the low area density at large ...
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Why are neutrino flavors equal to 1:1:1 after a long travel?

Neutrinos produced in the interaction of very high energy cosmic rays with the CMB are produced in the proportion $\nu_\mu:\nu_e:\nu_\tau=2:1:0$ because of the decays produced after the cosmic ray ...
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A good reference on cosmic ray?

I am looking for a good reference on cosmic ray, both galactic and solar. Does anyone have any suggestion? I'm looking for a reference that covers the production and propagation of cosmic rays in a ...
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What are SEP events in this article?

I am studying this paper; at page 5 it says: The occurrence of SEP events with fluences larger than the saturation limit was estimated to be less tha n one per year for the period the LPF ...
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What is the product of a proton interacting with the CMB?

Assuming the CMB is at 2.7 K, if a proton interacts with it, what would be the particles resulting of this collision? I read that at the GZK cut-off (~$10^{21}$ eV), there is photo-pion production, ...
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Where do ultrahigh-energy particles come from? [duplicate]

The most energetic particles that strike us from space, which include neutrinos as well as gamma-ray photons and various other bits of subatomic shrapnel, i.e the cosmic rays are sometimes so ...
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What is the Greisen-Zatsepin-Kuzmin (GZK) cutoff and why does it happen?

I was just wondering, what is the GZK cutoff point and why does it happen? Some say it is some sort of 'lattice' in the universe; https://www.google.ie/amp/s/io9.gizmodo.com/5950543/physicists-say-...
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What is cosmic ray albedo neutron decay (CRAND)?

I need a small description of what is cosmic ray albedo neutron decay (CRAND), where it comes from and what effects they have?
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TV snow and Big Bang

How come the white and black snow we see sometimes on TV is a result of the Big Bang? (the cosmic radiation) I meant the random dot pixel pattern of static in TVs, when there is no signal.
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Cloud Chamber not showing [closed]

I am trying to build a thermoelectric cloud chamber, it’s not showing any trails with a alpha source or cosmic rays. The only thing I see is alcohol vapour (small white dots). Using 99% isopropyl ...
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Cosmic ray shielding for electronics on Earth

There are plenty of topics discussing cosmic ray shielding, but they all put emphasis on spacecraft shielding, where things like radiation and mass are a big problem. So I decided to ask a question ...
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Higgs boson in space!

Given the fact that the Higgs-like boson has an invariant mass of about 125GeV, could we detect Higgses from Outer Space as we detect photons, neutrinos, protons or cosmic rays? As the Space is the ...
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Can cosmic rays show interference?

I read that interference in seen in waves with similar frequency, so if interference is possible for cosmic rays then wouldn't we need another cosmic ray to see this effect? If interference is ...
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Why can't we see particle tracks in clouds or dense fog? [duplicate]

We can see the tracks of charged particles in a cloud chamber. According to Wikipedia "A cloud chamber consists of a sealed environment containing a supersaturated vapor of water or alcohol". Also, in ...
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How come I never see cosmic rays in steam like they appear in a cloud chamber?

I just put like half a cup of water in a mason jar and put that in the microwave and accidentally left it in there for to long and it got boiling hot, then when I took it out and let it cool of course ...
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Why are there more trapped protons during solar minima?

Reading about trapped protons and eletrons in van Allen belts, I get the understanding that the number of trapped electrons increase during a solar maximum (which I find logical because we have more ...
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Is the CMB present in an artificial shielded vacuum?

I see the wiki page of cosmic microwave background (CMB) radiation says it is "present in all space"; I wonder, if I build a vacuum box with sufficient shielding, say a box with thick metal walls, and ...
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Measuring energy of muons with a calorimeter

As far as I know, the energy of muons can't be measured with the normal calorimeters that they measure the energy of other particles such as electrons, and it's due to its mass, it doesn't radiate, so ...
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