Cosmic Rays have fallen down the rabbit hole of post-normal science where they are semantically tortured by rival groups of astronomers and astrophysicists.
Radiation of all kinds reaches the top of the Earth’s atmosphere from outer space.
Traditionally, the science of observing electromagnetic radiation of any energy, from radio waves through visible light to gamma rays, is called astronomy.
When we observe particles or atomic nuclei, it is called cosmic ray physics, or in recent years, “particle astrophysics”.
Cosmic ray study using Air Shower Time coincidence Arrays
Chelkov, Demichev and Zhemchugov – Dzhelepov Laboratory of Nuclear Problems
Therefore, depending upon your chosen source Cosmic Rays are either: photons, particles or both.
Are Cosmic Rays Electromagnetic Radiation?
Some people still call high energy photons (x-rays and gamma rays) cosmic rays, and you’ll still see that in some textbooks.
The more common usage (at least in scientific circles) is to call particles cosmic rays, and to call photons either x-rays or gamma rays.
Dr. Eric Christian
Either way, both sides agree that the Earth is bombarded by cosmic “high energy”.
Cosmic rays are very high-energy particles…
Gamma radiation, also known as gamma rays, and denoted by the Greek letter γ, refers to electromagnetic radiation of extremely high frequency and therefore high energy per photon. Gamma rays are ionizing radiation, and are thus biologically hazardous.
Stellar X-ray astronomy is contributing toward a deeper understanding of… the interactions of high-energy radiation with the stellar environment.
Either way, both sides are talking about overlapping energy ranges.
Astronomers study “gamma rays” with energies that range “over 10 TeV” [1013 eV].
In astronomy, gamma rays are defined by their energy, and no production process need be specified.
The energies of gamma rays from astronomical sources range over 10 TeV, at a level far too large to result from radioactive decay.
Astrophysicists study “cosmic rays” with energies over 108 eV.
Unfortunately, this high energy, post normal turf war is further confused by the settled science brigade [at Wikipedia] who employ a degree of poetic license when they state that Cosmic Rays “mainly” originate from “outside the Solar System”.
Cosmic rays are very high-energy particles, mainly originating outside the Solar System.
The poetic license is revealed on the Wikipedia source page for their “Cosmic ray flux” which attributes the peak flux levels to “Solar Cosmic Rays” [see diagram above].
The flux of cosmic ray particles as a function of their energy.
The flux for the lowest energies (yellow zone) are mainly attributed to solar cosmic rays, intermediate energies (blue) to galactic cosmic rays, and highest energies (purple) to extragalactic cosmic rays
Presumably, the poetic license exercised by Wikipedia aims to prevent the casual reader realising that the flux of Solar Cosmic Rays [with an energy level of 109 eV] is “about 10,000 per square meter per second” at “Earth’s surface”.
The flux of incoming cosmic rays at the upper atmosphere is dependent on the solar wind, the Earth’s magnetic field, and the energy of the cosmic rays.
The combined effects of all of the factors mentioned contribute to the flux of cosmic rays at Earth’s surface.
For 1 GeV particles, the rate of arrival is about 10,000 per square meter per second.
Meanwhile, the hard core astrophysicists simply ignore Solar Cosmic Rays because they are focused upon the far more exciting Galactic and Extragalactic Cosmic Rays with energy levels above 1010 eV.
Preliminary results from the presently-operating Alpha Magnetic Spectrometer (AMS-02) on board the International Space Station show that positrons in the cosmic rays arrive with no directionality, and with energies that range from 10 GeV to 250 GeV, with the fraction of positrons to electrons increasing at higher energies.
IceCube Neutrino Observatory
… thus IceCube is sensitive mostly to high energy neutrinos, in the range of 1011 to about 1021 eV.
IceCube Quick Facts
275 million cosmic rays are detected by IceCube every day.
http://icecube.wisc.edu/gallery/view/140 [image 2 of 6]
The hard core Gamma Ray astronomers also ignore Solar Cosmic Rays because they are focused upon far more exciting things like bubbles and black holes in the Milky Way.
In November 2010, using the Fermi Gamma-ray Space Telescope, two gigantic gamma-ray bubbles, spanning about 25,000 light-years across, were detected at the heart of our galaxy.
These bubbles of high-energy radiation are suspected as erupting from a massive black hole or evidence of a burst of star formations from millions of years ago.
The soft core X-Ray astronomers also ignore Solar Cosmic Rays because they are focused upon far more exciting things like solar flares and coronal mass ejections.
The GOES 14 spacecraft carries on board a Solar X-ray Imager to monitor the Sun’s X-rays for the early detection of solar flares, coronal mass ejections, and other phenomena that impact the geospace environment.
However, with some perseverance [and a machete to cut through the thick undergrowth of obscuration and misdirection] it is possible to piece together the physical processes that occur when a high energy Cosmic Ray [of any denomination] encounters the planet Earth.
The first step occurs when a Cosmic Ray collides with a particle in Earth’s atmosphere.
The particle density in the outermost Exosphere is extremely sparse so the chances of a Cosmic Ray collision are low [but not impossible]. The chances of a collision increase exponentially as the Cosmic Ray descends through the Thermosphere, Mesosphere and into the Stratosphere where the majority of the Cosmic Rays finally collide with an atmospheric particle.
The next step in the story depends upon the energy level of the Cosmic Ray.
Low energy Cosmic Rays with energies “above a few MeV” [106 eV – which seems to define them as old fashioned Gamma Rays] trigger an Electromagnetic Shower which “emit photons”.
In particle physics, a shower is a cascade of secondary particles produced as the result of a high-energy particle interacting with dense matter.
The incoming particle interacts, producing multiple new particles with lesser energy; each of these then interacts in the same way, a process that continues until many thousands, millions, or even billions of low-energy particles are produced.
These are then stopped in the matter and absorbed.
An electromagnetic shower begins when a high-energy electron, positron or photon enters a material. At high energies (above a few MeV, below which photoelectric effect and Compton scattering are dominant), photons interact with matter primarily via pair production — that is, they convert into an electron-positron pair, interacting with an atomic nucleus or electron in order to conserve momentum.
High-energy electrons and positrons primarily emit photons, a process called bremsstrahlung.
These two processes (pair production and bremsstrahlung) continue until photons fall below the pair production threshold, and energy losses of electrons other than bremsstrahlung start to dominate.
An electromagnetic shower “photoshopped” from an illustration in:
Cosmic ray study using Air Shower Time coincidence Arrays
G. A. Chelkov, M. A. Demichev, A. S. Zhemchugov
Dzhelepov Laboratory of Nuclear Problems
Unsurprisingly, Earth scientists [like most other branches of science] prefer to ignore the lower energy Cosmic Rays originating from the Sun.
This makes it difficult to pinpoint exactly where the Electromagnetic Showers occur in the atmosphere.
However, the atmospheric absorption of Gamma Ray and X-Ray [see the STCI/JHU/NASA diagram above] appears to be concentrated in the Mesosphere and upper Stratosphere.
Closer inspection of this atmospheric region reveals the D Layer of the Ionosphere [located between 60 and 90 kilometres above the surface of the Earth] which appears [strangely enough] only during daylight hours.
The D layer is the innermost layer, 60 km (37 mi) to 90 km (56 mi) above the surface of the Earth.
In addition, with high Solar activity hard X-rays (wavelength < 1 nm) may ionize (N₂, O₂).
During the night cosmic rays produce a residual amount of ionization.
Recombination is high in the D layer, the net ionization effect is low, but loss of wave energy is great due to frequent collisions of the electrons (about ten collisions every msec).
Therefore, it is very likely that the majority of the Electromagnetic Showers [that are triggered by Solar Cosmic Rays] originate in the D Layer because:
1) The D Layer is purely a daytime phenomenon.
2) The D Layer is associated with atmosphere ionization caused by X-Rays [Cosmic Rays].
3) The low “net ionization effect” in the D Layer is indicative of a “electron-positron pair” driver.
“High-energy electrons and positrons” that “primarily emit photons” in an Electromagnetic Shower causes “fluorescence light that is emitted isotropically from the excitation of nitrogen molecules”.
as fluorescence light that is emitted isotropically from the excitation of nitrogen molecules.
Unsurprisingly, a nitrogen discharge tube emits a central white light [by mixing the Red, Orange, Yellow, Green, Blue, Indigo and Violet emission bands in the nitrogen spectra] surrounded by a violet/blue fluorescent haze.
Therefore, based upon sky observations, it seems highly likely that the daily charge-up of the D Layer in the Ionosphere is associated with the daily charge-up of nitrogen molecules which would fluoresce through red, orange and yellow at sunrise.
Thus, the fully charged D Layer can be expected to be a blue fluorescing smog of positrons, electrons and photons [a blue sky] that surrounds a central white light [the sun].
Similarly, the daily run down of the D Layer in the Ionosphere would be associated with the daily run down of nitrogen molecules which would fluoresce through yellow, orange and red at sunset.