I Can’t Sleep - Cosmic Rays | Calm Reading to Help You Sleep
Episode Date: February 17, 2024Ease into sleep with this calm bedtime reading as Benjamin explores the fascinating world of cosmic rays, offering gentle relief from insomnia and sleepless nights. You’ll learn how these high-energ...y particles travel through space, their discovery, and the role they play in our understanding of the universe. Benjamin’s soothing cadence turns scientific details into a relaxing journey, reducing stress and quieting the mind. No whispering or hypnosis—just peaceful, fact-filled storytelling designed to guide you into rest. Press play, let go of the day, and drift into deep, refreshing sleep. Want More? Request a Topic: https://www.icantsleeppodcast.com/request-a-topic Ad-Free Episodes: https://icantsleep.supportingcast.fm/ Shop Sleep-Friendly Products: https://www.icantsleeppodcast.com/sponsors Join the Discussion on Discord: https://discord.gg/myhGhVUhn7 This content is derived from the Wikipedia article on Cosmic Rays, available under the Creative Commons Attribution-ShareAlike (CC BY-SA) license. Read the full article: Wikipedia – Cosmic Rays. Happy sleeping! Learn more about your ad choices. Visit megaphone.fm/adchoices
Transcript
Discussion (0)
You're listening to a Glassbox media podcast.
What if I told you that most of the modern day self-help advice you've been hearing could actually make you worse?
The key to a better life isn't about feel-good gimmicks that sound catchy.
The Mentally Stronger Podcast gives you access to a licensed therapist who shares science-backed tools that will actually change your life.
Hi, I'm Amy Morin, psychotherapist, mental strength trainer, and international best-selling author.
In each episode, we cover research-back strategies, like how to stop relying on willpower and start
creating habits for lasting change.
And the five mental strength-building exercises you can do from your couch.
I also speak to world-class experts like Dr. Nicole Kane, who shares how to permanently
heal anxiety by addressing the root cause.
With over 200 episodes in our catalog, this podcast is for you if you're ready to crush
self-doubt, conquer challenges, and become stronger than ever with therapist-approved
strategies that can change your life. Listen to Mentally Stronger with Therapist Amy Morin, wherever
you get your podcasts. Welcome to the I Can't Sleep podcast, where I read random articles
from across the web to bore you to sleep with my soothing voice. I'm your host, Benjamin Boster.
Today's episode is from a Wikipedia article titled Cosmic Ray.
Cosmic rays or astroparticles are high-energy particles or clusters of particles,
primarily represented by protons or atomic nuclei,
that move through space at nearly the speed of light.
They originate from the sun, from outside of the solar system in our galaxy,
and from distant galaxies.
Upon impact with Earth's atmosphere, cosmic rays produce showers of secondary particles,
some of which reach the surface, although the bulk are deflected off into space by the magnetosphere
or the heliosphere. Cosmic rays were discovered by Victor Hess in 1912 in balloon experiments,
for which he was awarded the 1936 Nobel Prize in physics.
Direct measurement of cosmic rays, especially at least out of the world.
lower energies has been possible since the launch of the first satellites in the late 1950s.
Particle detectors, similar to those used in nuclear and high-energy physics,
are used on satellites and space probes for research into cosmic rays.
Data from the Fermi Space Telescope 2013 have been interpreted as evidence that a significant
fraction of primary cosmic rays originate from the supermarkets.
supernova explosion of stars. Based on observations of neutrinos and gamma rays, the Blazart
TXS 0506 plus 056 in 2018, active galactic nuclei also appear to produce cosmic rays. The term
ray as an optical ray seems to have arisen from an initial belief due to their penetrating power,
that cosmic rays were mostly electromagnetic radiation.
Nevertheless, following wider recognition of cosmic rays as being various high-energy particles with intrinsic mass,
the term rays was still consistent with then-known particles, such as cathode rays, canal rays, alpha rays, and beta rays.
Meanwhile, cosmic ray photons, which are quanta of electromagnetic,
magnetic radiation, and so have no intrinsic mass, are known by their common names, such as gamma rays or x-rays, depending on their photon energy.
Of primary cosmic rays which originate outside of Earth's atmosphere, about 99% are the bare nuclei of common atoms stripped of their electron shells,
and about 1% are solitary electrons, that is, one type of beta particle.
Of the nuclei, about 90% are simple protons, i.e. hydrogen nuclei.
9% are alpha particles, identical to helium nuclei,
and 1% are the nuclei of heavier elements, called H-Z-E ions.
These fractions vary highly over the energy range of cosmic rays.
A very small fraction are stable particles of antimatter,
such as positrons or antiprotons.
The precise nature of this remaining fraction
is an area of active research.
An active search from Earth orbit
for anti-alpha particles has failed to detect them.
Upon striking the atmosphere,
cosmic rays violently burst atoms into other pits of matter,
producing large amounts of pyons and muons,
produced from the decay of charged pyons, which have a short half-life, as well as neutrinos.
The neutron composition of the particle cascade increases at lower elevations,
reaching between 40% and 80% of the radiation at aircraft altitudes.
Of secondary cosmic rays, the charged pyons produced by primary cosmic rays in the atmosphere
swiftly decay, emitting muons. Unlike pyons, these muons do not interact strongly with matter,
and can travel through the atmosphere to penetrate even below ground level. The rate of muons
arriving at the surface of the earth is such that about one per second passes through a volume
the size of a person's head. Together with natural local radioactivity, these muons are a significant
and cause of the ground-level atmospheric ionization that first attracted the attention of scientists,
leading to the eventual discovery of the primary cosmic rays arriving from beyond our atmosphere.
Cosmic rays attract great interest practically due to the damage they inflict on microelectronics
and life outside the protection of an atmosphere and magnetic field,
and scientifically because the energies of the most energetic,
ultra-high energy cosmic rays have been observed to approach 3 times 10 to the 20th electron volts.
This is slightly greater than 21 million times the design energy of particles accelerated by the large Hadron Collider, 14 terra-electron volts.
One can show that such enormous energies might be achieved by means of the centrifugal mechanism of acceleration in active galactic nuclei.
At 50 joules, the highest energy ultra-high-energy cosmic rays, such as the OMG particle recorded in 1991,
have energies comparable to the kinetic energy of a 90-kilometer per hour, or a 56-mile-per-hour baseball.
As a result of these discoveries, there has been interest in investigating cosmic rays of even greater energies.
Most cosmic rays, however, do not have such extreme energies.
The energy distribution of cosmic rays peaks at 300 mega electron volts.
After the discovery of radioactivity by Henri Beccarell in 1896,
it was generally believed that atmospheric electricity, ionization of the air,
was caused only by radiation from radioactive elements
and the ground or the radioactive gases or isotopes of radon they produce.
Measurements of increasing ionization rates at increasing heights above the ground
during the decade from 1900 to 2010 could be explained as due to absorption of the ionization
radiation by the intervening air. In 1909, Theodore Wolfe developed an electromagnet,
a device to measure the rate of ion production inside a hermetical seal's container,
and used it to show higher levels of radiation at the top of the Eiffel Tower than at its base.
However, his paper published in Physicalis of Zitescript was not widely accepted.
In 1911, Domenico Pacini observed simultaneous variations of the rate of ionization over a lake,
over the sea and at a depth of three meters from the surface.
Pacini concluded from the decrease of radioactivity underwater
that a certain part of the ionization must be due to sources
other than the radioactivity of the earth.
In 1912, Victor Hess carried three enhanced accuracy wolf electrometers
to an altitude of 5,300 meters in a free balloon flight.
He found the ionization rate increased approximately fourfold over the rate at ground level.
Hess ruled out the sun as a radiation source by making a balloon ascent during a near total eclipse.
With the moon blocking much of the sun's visible radiation,
Hess still measured rising radiation at rising altitudes.
He concluded that the results of the observations seem,
most likely to be explained by the assumption that radiation of very high penetrating power
enters from above into our atmosphere. In 1913 to 1914, Werner-Kohlhurster confirmed Victor
Hess's earlier results by measuring the increased ionization enthalpy rate at an altitude of
nine kilometers. Hess received the Nobel Prize in physics in 1936 for his discovery.
Bruno Rossi wrote that
in the late 1920s and early 1930s,
a technique of self-recording
telescopes carried by balloons
into the highest layers of the atmosphere
or sunk to great depths underwater
was brought to an unprecedented degree of perfection
by the German physicist Eric Regner
and his group.
To these scientists, we owe some of the most accurate measurements
ever made of cosmic ray ionization as a function of altitude and depth.
Ernest Rutherford stated in 1931 that,
thanks to the fine experiments of Professor Milliken
and the even more far-reaching experiments of Professor Regener,
we have now got, for the first time,
a curve of absorption of these radiations in water,
which we may safely rely upon.
In the 1920s, the term cosmic ray was coined,
joined by Robert Milliken, who made measurements of ionization due to cosmic rays from deep
underwater to high altitudes and around the globe.
Milliken believed that his measurements prove that the primary cosmic rays were gamma rays,
i.e. energetic photons.
He proposed a theory that they were produced in interstellar space as byproducts of the fusion
of hydrogen atoms into the heavier elements, and that,
secondary electrons were produced in the atmosphere by Compton scattering of gamma rays.
In 1927, while sailing from Java to the Netherlands, Jacob Clay found evidence, later confirmed
in many experiments, that cosmic ray intensity increases from the tropics to mid-latitudes,
which indicated that the primary cosmic rays are deflected by the geomagnetic field
and must therefore be charged particles, not photoccurys.
In 1929, Both and Colerster discovered charged cosmic ray particles that could penetrate 4.1
centimeters of gold.
Charged particles of such high energy could not possibly be produced by photons from Milliken's
proposed interstellar fusion process.
In 1930, Bruno Rossi predicted a difference between the intensities of cosmic rays arriving
from the east and the west that depends upon the charge of the primary particles, the so-called
east-west effect. Three independent experiments found that the intensity is, in fact, greater
from the west, proving that most primaries are positive. During the years from 1930 to 1945,
a wide variety of investigations confirmed that the primary cosmic rays are mostly protons,
and the secondary radiation produced in the atmosphere as primarily electrons, photons, and muons.
In 1948, observations with nuclear emulsions carried by balloons to near the top of the atmosphere
showed that approximately 10% of the primaries are helium nuclei, alpha particles,
and 1% are nuclei of heavier elements such as carbon, iron, and lead.
during a test of his equipment for measuring the east-west effect,
Rossi observed that the rate of near-simultaneous discharges of two widely separated Geiger counters
was larger than the expected accidental rate.
In his report on the experiment, Rossi wrote,
It seems that once in a while the recording equipment is struck by very extensive showers of particles,
which causes coincidences between the counters,
even placed at large distances from one another.
In 1937, Pierre Auger, unaware of Rossi's earlier report,
detected the same phenomenon and investigated it in some detail.
He concluded that high-energy primary cosmic ray particles interact with air nuclei high in the atmosphere,
initiating a cascade of secondary interactions that ultimately yield a shower of electrons
and photons at reach crown level.
Soviet physicist Sergei Vernov was the first to use radiosans
to perform cosmic ray readings with an instrument carried to high altitude by a balloon.
On the 1st of April 1935, he took measurements at heights up to 13.6 kilometers,
using a pair of Geiger counters in an anti-coincidence circuit to avoid counting secondary ray showers.
Homi J. Baba derived an expression for the probability of scattering positrons by electrons,
a process now known as the Baba scattering.
His classic paper, jointly with Walter Heitler, published in 1937, described how primary cosmic rays from space
interact with the upper atmosphere to produce particles observed at the ground level.
Baba and Heitler explained the cosmic ray shower formation,
by the cascade production of gamma rays and positive and negative electron pairs.
Measurements of the energy and arrival directions of the ultra-high-energy primary cosmic rays
by the techniques of density sampling and fast timing of extensive air showers
were first carried out in 1954 by members of the Rossi Cosmic Ray Group
at the Massachusetts Institute of Technology.
The experiment employed 11 scintillation-discuited.
detectors arranged within a circle 460 meters in diameter on the grounds of the Agassiz
Station of the Harvard College Observatory. From that work and from many other experiments
carried out all over the world, the energy spectrum of the primary cosmic rays is now known
to extend beyond 10 to the 20th electron volts. A huge air shower experiment called the Auger
Project is currently operated at a site on the Pompas of Argentina.
by an international consortium of physicists.
The project was first led by James Cronin,
winner of the 1980 Nobel Prize in Physics from the University of Chicago,
and Alan Watson of the University of Leeds,
and later by scientists of the international Pierre Auger collaboration.
Their aim is to explore the properties and arrival directions
of the very highest energy primary cosmic rays.
The results are expected to have important implications for particle physics and cosmology,
due to a theoretical Grisen-Zetzepin-Gusman limit,
the energies of cosmic rays from long distances,
about 160 million light years,
which occurs above 10 to the 20th electron volts,
because of interactions with the remnant photons from the Big Bang origin of the universe.
Currently, the Pierre Auger Observatory is undergoing an upgrade to improve,
improve its accuracy and find evidence for the yet unconfirmed origin of the most energetic cosmic rays.
High-energy gamma rays were finally discovered in the primary cosmic radiation by an MIT experiment
carried on the OS-O-3 satellite in 1967.
Components of both galactic and extra-galactic origins were separately identified at intensities
much less than 1% of the primary charged particles.
Since then, numerous satellite gamma-ray observatories have mapped the gamma-rays sky.
The most recent is the Fermi Observatory, which has produced a map showing a narrow band of gamma-ray intensity
produced in discrete and diffuse sources in our galaxy,
and numerous point-like extra-galactic sources distributed over the celestial sphere.
Early speculation on the sources of cosmic rays included in 19,000,
34 proposal by Bade and Zwicki, suggesting cosmic rays originated from supernovae.
A 1948 proposal by Horace W. Babcock suggested that magnetic variable stars could be a source of cosmic rays.
Subsequently, Sakito at all identified the Crab Nebula as a source of cosmic rays.
Since then, a wide variety of potential sources for cosmic rays began to surface.
surface, including supernovae, active galactic nuclei, quasars, and gamma-ray bursts.
Later experiments have helped to identify the sources of cosmic rays with greater certainty.
In 2009, a paper presented at the International Cosmic Ray Conference by scientists at the
Pierre Auger Observatory in Argentina, showed ultra-high energy cosmic rays originating from
a location in the sky, very close to the radio galaxy Centaurus A,
although the authors specifically stated that further investigation would be required
to confirm Centaurus A as a source of cosmic rays.
However, no correlation was found between the incidence of gamma-ray bursts and cosmic rays,
causing the authors to set upper limits as low as 3.4 times 10 to the negative 6 times ERG times
CM to the negative 2 on the flux of 1 giga electron volt minus 1 terra electron volt cosmic rays
from gamma ray bursts. In 2009, supernovae were said to have been pinned down as a source of
cosmic rays, a discovery made by a group using data from the very large telescope.
This analysis, however, was disputed in 2011 with data from Pamela, which revealed
that spectral shapes of hydrogen and helium nuclei are different and cannot be described well
by a single power law, suggesting a more complex process of cosmic ray formation.
In February 2013, though, research analyzing data from Fermi revealed through an observation
of neutral pion decay that supernovae were indeed a source of cosmic rays, with each explosion
producing roughly 3 times 10 to the 42nd minus 3 times 10 to the 43rd joules of cosmic rays.
Supernovae do not produce all cosmic rays, however,
and the proportion of cosmic rays that they do produce
is a question which cannot be answered without deeper investigation.
To explain the actual process in supernovae an active galactic nuclei
that accelerates the stripped atoms,
physicists use shock-front acceleration as,
a plausibility argument. In 2017, the Pierre Auger collaboration published the observation
of a weak anisotropy in the arrival directions of the highest energy cosmic rays.
Since the galactic center is in the deficit region, this anisotropy can be interpreted
as evidence for the extra-galactic origin of cosmic rays at the highest energies.
This implies that there must be a transition energy from galactic to extragalactic sources,
and there may be different types of cosmic ray sources contributing to different energy ranges.
Cosmic rays can be divided into two types, galactic cosmic rays, GCR, and extra
galactic cosmic rays, i.e. high energy particles originating outside the solar system.
Solar-energetic particles, high-energy particles, predominantly protons, emitted by the sun, primarily in solar eruptions.
However, the term cosmic ray is often used to refer to only the extrasolar flux.
Cosmic rays originate as primary cosmic rays, which are those originally produced in various atmospheric processes.
primary cosmic rays are composed mainly of protons and alpha particles, 99%,
with a small amount of heavier nuclei, roughly around 1%,
and an extremely minute proportion of positrons and antiprotons.
Secondary cosmic rays caused by a decay of primary cosmic rays
as they impact in atmosphere include photons,
Hadrons and leptons, such as electrons, positrons, muons, and pyons.
The latter three of these were first detected in cosmic rays.
Primary cosmic rays mostly originate from outside the solar system,
and sometimes even outside the Milky Way.
When they interact with Earth's atmosphere, they are converted to secondary particles,
The mass ratio of helium to hydrogen nuclei, 28%, is similar to the primordial elemental abundance ratio of these elements, 24%.
The remaining fraction is made up of the other heavier nuclei that are typical nucleosynthesis end products,
primarily lithium, beryllium, and boron.
These nuclei appear in cosmic rays in greater abundance, roughly 1%,
than in the solar atmosphere where they are only about 10 to the negative third as abundant by number as helium.
Cosmic rays composed of charged nuclei heavier as in helium are called H-Z-E-Ions.
Due to the high-charge and heavy nature of H-C-E-Ions,
their contribution to an astronaut's radiation dose in space is significant
even though they are relatively scarce.
This abundance difference is a result of the way in which secondary cosmic rays are formed.
Carbon and oxygen nuclei collide with interstellar matter to form lithium, beryllium, and boron,
and a process termed cosmic ray spallation.
Spallation is also responsible for the abundances of scandium, titanium, benadium, and manganese,
ions in cosmic rays, produced by collisions of iron and nickel nuclei with interstellar
matter. At high energies, the composition changes, and heavier nuclei have larger abundances
in some energy ranges. Current experiments aim at more accurate measurements of the composition
at high energies. Satellite experiments have found evidence of positrons and a few antiprotons
in primary cosmic rays, amounting to less than 1% of the particles in primary cosmic rays.
These do not appear to be products of large amounts of antimatter from the Big Bang,
or indeed complex antimatter in the universe.
Rather, they appear to consist of only these two elementary particles, newly made in energetic processes.
Preliminary results from the presently operating alpha magnetic spectacles.
Electrometer, AMS-O-2, on board the International Space Station, show that positrons in the cosmic rays arrive with no directionality.
In September 2014, new results with almost twice as much data were presented in a talk at CERN and published in physical review letters.
A new measurement of positron fraction up to 500 giga electron volts was reported, showing that positron fraction peaks,
at a maximum of about 16% of total electron plus positron events, around an energy of 275 plus or minus
32 giga electron volts. At higher energies up to 500 giga electron volts, the ratio of positrons
to electrons begins to fall again. The absolute flux of positrons also begins to fall
before 500 giga electron volts, but peaks at energies far higher than electron energies,
which peak at about 10 giga electron volts. These results on interpretation have been suggested to be
due to positron production and annihilation events of massive dark matter particles. Cosmic ray antiprotons
also have a much higher average energy than their normal matter counterparts protons.
They arrive at Earth with a characteristic energy maximum of 2 giga electron volts,
indicating their production in a fundamentally different process from cosmic ray protons,
which on average have only 1-6th of the energy.
There is no evidence of complex antimatter atomic nuclei,
such as antihelium nuclei, i.e. anti-alpha particles in cosmic rays.
These are actively being searched for.
A prototype of the AMS-O-2 designated AMS-O-1 was flown into space aboard the space shuttle discovery on STS91 in June 1998.
By not detecting any antihelium at all, the AMS-O-1 established an upper limit of 1.1 times 10 to the negative 6 for the antihelium-to-Helux ratio.
When cosmic rays enter the Earth's atmosphere, they collide with atoms and molecules, mainly oxygen and nitrogen.
The interaction produces a cascade of lighter particles, a so-called air shower secondary radiation that rains down, including x-rays, protons, alpha particles, ions, ions, electrons, neutrinos, and neutrons.
All of the secondary particles produced by the collision continue onward on paths within about
one degree of the primary particle's original path.
Typical particles produced in such collisions are neutrons and charge mesons, such as positive
or negative pyons and caons.
Some of these subsequently decay into muons and neutrinos, which are able to reach the surface
of the earth. Some high-energy muons even penetrate from some distance into shallow minds,
and most neutrinos traverse the Earth without further interaction. Others decay into photons,
subsequently producing electromagnetic cascades. Hence, next to photons, electrons and positrons
usually dominate in air showers. These particles, as well as muons, can be easily detected by many
types of particle detectors, such as cloud chambers, bubble chambers, water charenkoff, or scintillation
detectors. The observation of a secondary shower of particles and multiple detectors at the same
time is an indication that all of the particles came from that event. Cosmic rays impacting other
planetary bodies in the solar system are detected indirectly by observing high-energy gamma-ray
emissions by gamma-ray telescope. These are distinguished from radioactive decay processes
by their higher energies above about 10 mega-electron volts. 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. At distances of about 94 astronomical units from the sun, the solar
wind undergoes a transition called the termination shock, from supersonic to subsonic speeds.
The region between the termination shock and the heliopause acts as a barrier to cosmic rays,
decreasing the flux at lower energies by about 90%.
However, the strength of the solar wind is not constant, and hence it has been observed
that cosmic ray flux is correlated with solar activity.
In addition, the Earth's magnetic field acts to deflect cosmic rays from its surface,
giving rise to the observation that the flux is apparently dependent on latitude,
longitude, and azimuth angle.
The combined effects of all of the factors mentioned contribute to the flux of cosmic rays at Earth's surface.
In the past, it was believed that the cosmic ray flux remained fairly constant over time.
However, recent research suggests one and a half to two-fold millennium time scale
changes in the cosmic ray flux in the past 40,000 years. The magnitude of the energy of cosmic
ray flux in interstellar space is very comparable to that of other deep space energies.
Cosmic ray energy density averages about one electron volt per cubic cubic centimeter of interstellar
space, or approximately one electron volt per cubic meter cubed, which is comparable to
to the energy density of visible starlight at .3 electron volts per cubic meter cubed.
The galactic magnetic field energy density assumed three micro-gauss, which is approximately
.25 electron volts per cubic meter cubed, or the cosmic microwave background CMB radiation
energy density at approximately .25 electron volts per cubic meter cubed.
There are two main classes of detection methods. First, the direct detection of the primary
cosmic rays in space or at high altitude by balloon-borne instruments. Second, the indirect direction
of secondary particle, i.e. extensive air showers at higher energies. While there have been proposals
and prototypes for space and balloon-borne detection of air-
showers, currently operating experiments for high-energy cosmic rays are ground-based.
Generally, direct detection is more accurate than indirect detection. However, the flux of cosmic rays
decreases with energy, which hampers direct detection from the energy range about one petta-electron
volt. Both direct and indirect detection are realized by several techniques.
Direct detection is possible by all kinds of particle detectors at the ISS on satellites or high-altitude balloons.
However, there are constraints in weight and size limiting the choices of detectors.
An example for the direct detection technique is a method based on nuclear tracks developed by Robert Fletcher, P. Buford Price, and Robert M. Walker, for use in high-altitude.
In this method, sheets of clear plastic, like .25 millimeter lexin polycarbonate, are stacked together and exposed directly to cosmic rays in space or high altitude.
The nuclear charge causes chemical bond breaking or ionization in the plastic.
At the top of the plastic stack, the ionization is less due to the high cosmic ray speed.
As the cosmic ray speed decreases due to deceleration in the stack, the ionization increases along the path.
The resulting plastic sheets are etched or slowly dissolved in warm caustic sodium hydroxide solution
that removes the surface material at a slow known rate.
The caustic sodium hydroxide dissolves a plastic at a faster rate along the path to
of the ionized plastic.
The net result is a conical edge pit in the plastic.
The edge pits are measured under a high power microscope,
and the edge rate is plotted as a function of the depth in the stacked plastic.
This technique yields a unique curve for each atomic nucleus from 1 to 92,
allowing identification of both the charge and energy of the cosmic ray
that traverses the plastic stack.
The more extensive the ionization along the path, the higher the charge.
In addition to its uses for cosmic ray detection,
a technique is also used to detect nuclei created as products of nuclear fission.
There are several ground-based methods of detecting cosmic rays currently in use,
which can be divided in two main categories.
The detection of secondary particles form in extensive air showers, EAS, by various types of particle detectors,
and the detection of electromagnetic radiation emitted by EAS in the atmosphere.
Extensive air shower arrays made of particle detectors measure the charged particles which pass through them.
EAS arrays can observe a broad area of the sky,
and can be active more than 90% of the time.
However, they are less able to segregate background effects from cosmic rays than can air Cherenkov telescopes.
Most state-of-the-art EAS arrays employ plastic scindulators.
Also, water, liquid or frozen, is used as a detection medium through which particles pass and produce
char and cove radiation to make them detectable.
Therefore, several arrays use water ice
charingov detectors as alternative or in addition to
scintillators. By the combination of several detectors,
some EAS arrays have the capability to distinguish muons from
lighter secondary particles, photons, electrons, positrons.
The fraction of muons among the secondary particles is one traditional way to estimate the mass composition of the primary cosmic rays.
An historic method of secondary particle detection still used for demonstration purposes involves the use of cloud chambers to detect the secondary muons created when a pion decays.
Cloud chambers in particular can be built from widely available materials and can be constructed.
even in a high school laboratory.
A fifth method involving bubble chambers can be used to detect cosmic ray particles.
More recently, the Seymus devices and pervasive smartphone cameras
have been proposed as a practical distributed network to detect air showers from ultra-high-energy cosmic rays.
The first app to exploit this proposition was the Krafis' cosmic rays found in
smartphones experiment.
In 2017, the Credo, Cosmic Ray extremely distributed observatory collaboration
released the first version of its completely open-source app for Android devices.
Since then, the collaboration has attracted the interest in support of many scientific institutions,
educational institutions, and members of the public around the world.
Future research has to show in what aspects this new,
technique can compete with dedicated EAS arrays.
The first detection method in the second category is called the Air Cherenkov telescope,
designed to detect low-energy cosmic rays by means of analyzing their Cherincoff radiation,
which for cosmic rays are gamma rays emitted as they travel faster than the speed of light
in their medium, the atmosphere.
While these telescopes are extremely good at distinguishing between background radiation and that
of cosmic ray origin, they can only function well on clear nights without the moon shining,
have very small fields of view, and are only active for a small percent of the time.
A second method detects the light from nitrogen fluorescence caused by the exitation of nitrogen
in the atmosphere, by particles moving through the atmosphere.
This method is the most accurate for cosmic rays at highest energies, in particular when
combined with EAS arrays of particle detectors.
Similar to the detection of Cherenkov light, this method is restricted to clear nights.
Another method detects radio waves emitted by air showers. This technique has a high
duty cycle similar to that of particle detectors. The accuracy of this technique was improved in the
last years as shown by various prototype experiments and may become an alternative to the detection
of atmospheric Cherenkov light and fluorescence light, at least at high energies.
Cosmic rays ionize nitrogen and oxygen molecules in the atmosphere, which leads to a number
of chemical reactions.
Cosmic rays are also responsible for the continuous production of a number of unstable isotopes,
such as carbon 14 in the Earth's atmosphere.
Cosmic rays kept the level of carbon 14 in the atmosphere roughly constant,
70 tons, for at least the past 100,000 years,
until the beginning of above-ground nuclear weapons testing in the early 1950s,
This fact is used in radiocarbon dating.
Cosmic rays have sufficient energy to alter the states of circuit components
and electronic integrated circuits,
causing transient errors to occur,
such as corrupted data and electronic memory devices,
or incorrect performance of CPUs,
often referred to as soft errors.
This has been a problem in electronics at extremely high altitude,
such as in satellites,
but with transistors becoming smaller and smaller,
this is becoming an increasing concern
in ground-level electronics as well.
Studies by IBM in the 1990s
suggests that computers typically experience
about one cosmic ray-induced error
per 256 megabytes of RAM per month.
To alleviate this problem,
the Intel Corporation is proposed
a cosmic ray detector that could be integrated into future high-density microprocessors,
allowing the processor to repeat the last command following a cosmic ray event.
ECC memory is used to protect data against data corruption caused by cosmic rays.
In 2008, data corruption in a flight control system caused an Airbus A330 airliner
to twice plunge hundreds of feet, resulting in injuries to multiple passengers and crew members.
Cosmic rays were investigated among other possible causes of the data corruption,
but were ultimately ruled out as being very unlikely.
In August 2020, scientists reported that ionizing radiation from environmental radioactive materials
and cosmic rays may substantially limit the coherence times of cubits if they are not shielded adequately,
which may be critical for realizing fault-tolerant superconducting quantum computers in the future.
