Often these particles travel very fast at significant fractions of light speed. Unlike most type of EM radiation, particle radiation can be quite destructive, though some (neutrinos) do almost nothing at all.
Baryonic vs Non-baryonic
Particles come in all sorts of flavors. Generally though the kinds of particles you and I might be interested in are what are called baryonic matter. To non-particle physics baryonic matter is all the matter you will ever need to worry about. Non-baryonic matter includes such elusive concepts as photons, the purely theoretical Higgs boson (which suposedly gives the other particles mass), practically philosophical phonons (which are what happens when sounds collapse their wave state, whatever that means). Baryonic matter on the other hand is familiar stuff like protons, neutrons, electrons, antimatter and many more exotic particles. Most importantly to me baryonic matter particles actually tend occasionally act like particles rather than behaving like ripples is spacetime. Though baryonic particles may cause ripples in spacetime, they are almost never said to be ripples in spacetime. The same can not be said for non-baryonic particles.
So particle radiation is basically like a hail of very tiny very fast BB pellets.
Electric charge
Many type particle radiation consist of particles that have positive or negative electric charge. Alpha particles, beta particles and cosmic rays all have electric charge.
The atoms in your body, and most everyday substances, are said to be electrically neutral. This is only true when atoms are relatively small (nearly always). When we are talking about particles though, atoms are much much larger.
The atom is surrounded by a shell of negatively charged electroness. The nucleus on the other hand is a densely packed cluster of positively charged protons and electrically neutral neutrons. The whole thing is held together by forces that are beyond my (and most peoples) understanding.
The thing is though, while electrons might be electrically attracted to the nucleus something called Weak force (seriously look it up) prevents the electrons from colliding with the protons (though if that did happen charges would cancel and you would get a neutron, don't ask me how they know this). The electrons are only weakly connected to the nucleus. Like rebellious teenagers electrons can, and do, leave the atom if given the right influences.
Chemistry
Chemistry happens when electrons from one atom aren't content to stay with that atom but windup traveling with other atoms.
Covalent, or molecular bonds are when two atoms share electrons with each other. This is the strongest type of bond.
Metallic bonds are when electrons are shared throughout a large crystal structure of atoms. This is what makes metals are conductive.
Ions are atoms that are missing, or have an extra, electron and consequently carry electric charge. Ionic bonds are when one atom takes an electron from another atom to complete an eight electron shell (this is like a greedy stamp collector stealing your stamps to complete his set). This creates one negatively charged and one positively charged atom. The two consequently stick to each other. Ionic bonds dissociate in water.
Ionizing radiation
Imagine if you will, high speed charged particles reigning down on our placid molecularly bonded atoms. If the charged particle is moving slow enough they will actually bounce harmlessly off the atoms, possibly imparting momentum but in no way altering the atom or its relationships with nearby atoms. This is because even electrically neutral atoms have electrically charged parts.
Most of the time though the charged particle are moving very fast. As they zip along they ionize many atoms in or near their flight path. The high speed electric field strips atoms of their electrons. This usually destroys whatever chemistry might have been going on.
What once was a segment of DNA that told your cells how to make that unique hue of your eyes now says nothing, it has been ripped to shreds by ionizing radiation. You cell goes to work trying to repair the DNA, but this is like trying to reassemble documents after they have been to the shredder. Now the instruction seem to be telling the cell to reproduce ceaselessly and ignore all pleas from your body to stop.
Months later the descendents of this cell have now formed what is known as tumor. Before you die of cancer the doctors have a number of gambits they would like to try. One of these is to blast your tumor with radiation.
This may sound like fighting fire with gasoline but it actually makes sense. It was really a fluke that created the tumor in the first place. Blasting the same cells again would cause the DNA to say something else this time, assuming the cells don't die instantly which they would.
EM radiation can also be ionizing radiation. This hinges on frequency (wavelength) rather than total intensity.
Radioactive Decay
Certain configurations (actually most configurations out of whats possible) of protons and neutrons are intrinsically unstable. They can emit alpha, beta and gamma radiation until they reach a stable configuration.
Nucleons are the components of an atomic nucleus. You should probably know by now that these are protons and neutrons.
Mass number is the total number of nucleons. Uranium 235 has a mass number of 235 nucleons.
Atomic number is the number of protons. This determines chemical properties and what element an atom is.
An isotope has a specific atomic number and mass number. All uranium isotopes have the same atomic number but only Uranium-235 has a mass number of 235.
Decay Modes
Alpha decay is when an unstable (usually large) isotope gives up a helium size chunk of its nucleus in order to reach a more stable state. Alpha particles are just helium atoms that have no electrons and move at excessive speeds. Alpha decay reduces mass number by 4 and atomic number by 2.
Beta decay happens when nuclei have too many or too few neutrons. A neutron can release energy and form a proton and an electron. A proton can turn into a neutron by absorbing energy and releasing a positron. A positron is like an electron only with positive charge (actually its the anti-electron). Electrons and positrons are known collectively as beta particles. Beta particles are ejected from the nucleus at high speeds by the weak force. Beta decay will reduce or increase atomic number by 1 while conserving mass number. Beta particles have very little mass.
Gamma decay is just when the nucleus needs to release excess energy. Gamma rays are released but the nucleus does not need to change mass or atomic number to do this. Often gamma decay follows immediately after other decay modes that may have left the nucleus in an excited state.
A decay chain is the chain of radioactive unstable isotopes a nucleus will transition through until it reaches a non-radioactive stable isotope.
Half life is the amount of time it takes for statistically half of an isotope to decay into something else. Although some isotopes have half lives of millions of years, most decay in no time at all. The isotopes that stick around longer are more stable and less radioactive.
Gamma radiation is the most penetrating. It can go right through your skin and even your hazmat suit with no trouble. The best precaution is a nice thick layer of lead.
Beta and alpha radiation are less penetrating and simple rubber hazmat suit is ample protection. The danger with alpha and beta sources is contamination.
Nuclear Contamination
So you hear that the nuclear power plant is spilling nuclear radiation into the ground water. It must be having affect on peoples minds because they seem to think that the noun form of the verb radiate can somehow be a substance.
Can I spread intimidation on bread or sprinkle consternation on my flowerbed? No I can not.
Radioactive substances can leak. This is known as contamination. Nuclear contamination is scary because if it isn't handled properly a lot of people are going to get sick, the kind of sick you don't get better from.
Blowups happen. Your nuclear plant might only be designed to handle acts of god of certain magnitude. Something bigger could come along and screw things up. Though every safeguard may prevent it, sabotage or even simple negligence can conceivably cause contamination as well.
Though for every eventuality there is an SOP (standard operating procedure). There is reason for this. While it becomes increasingly expensive to protect a power plant from increasingly unlikely catastrophes it cost relatively little to run simulations and write documentation of steps to control the extent of damage is in those scenarios.
If you are unfortunate enough to be near a contamination there are steps that you can take that could conceivable prevent you from ever developing ill health effects.
Stay away from milk and dairy. Meat and fish are also dangerous. The goods already in your pantry before the spill as well as food from other non-contaminated areas should be totally safe.
Iodine pills keep iodine out. Your body doesn't "need" iodine to fight radiation. Rather iodine tablets clog your system with non radioactive iodine. This prevents radioactive iodine from being absorbed latter thereby averting thyroid cancer.
Listen to the authorities. They have a lot more training with this sort of thing than you.
When asked, evacuate. Evacuation is a good thing. It means that you are not already contaminated. If you get cancer later on in life its because you kept smoking cigarettes, you dumbass. Remember, as with any type of contamination the alternative to evacuation is quarantine.
Usually the worry with contamination is a chronic doses of radiation as the radiation lingers in a contaminated person for an extended period of time.
Neutron Radiation
Neutrons are not produced in nuclear decay and they carry no electric charge. The pass right through electron shells like they are not even there. They eventually slam into the nucleus and do numerous things to it. Adding a neutron increases mass number by 1. It also adds energy. The old isotopes may have been stable but the new one probably isn't. This causes it to transmute into new elements entirely.
Although neutron radiation does not ionize you can see why it is dangerous to people. It can make non radioactive materials radioactive without physically contaminating it. It can weaken strong materials by altering the elemental makeup.
Free moving neutrons are only created in nuclear fission and fusion reactions. Neutrons are actually a vital part of sustaining power generating nuclear reactions.
Neutron activation analysis is a really high tech way to measure exactly what and how much elements and isotopes something has. Scientist who need to radio date something like a fossil typically use x-ray spectrometry. Though x-ray spectrometers are relatively cheap and even portable there is a limit to their accuracy.
I had the privilege once of working as an intern at a research reactor. This reactor doesn't produce power. It only produces neutrons. It does so on demand for the sole purpose of neutron activation analysis. This reactor is incredibly safe. Nuclear meltdown is impossible.
Neutrino Radiation
Neutrinos like neutrons have no electrons and are also produced in nuclear reactions. Unlike neutrons and virtually every other type of radiation no amount of shielding in the world can stop the onslaught of neutrinos. Sounds dangerous right? Well no, not really.
Neutrinos interact very weakly with matter. So weakly in fact that neutrinos from the sun will often pass right through the planet earth entirely without so much as an atomic jostle. They have proven very difficult to detect.
Cosmic Rays
These are fragments of supernova or even weirder processes. Cosmic Rays are composed of heavy nuclei that are traveling close to the speed of light. They are quite hazardous to your health. They are bombarding the planet all the time. Metal shielding actually makes the problem worse because as the cosmic rays are slowed down by the atoms in the metal they release energy in the form of intense x-rays. This is called the bremsstrahlung or braking radiation.
Why are we surviving this onslaught? We aren't. The earth's magnetosphere actually deflects this stuff. Astronauts are not so immune. They have reported fireworks in their vision, even when they close their eyes. This is the result of cosmic rays striking their optic nerve. If just that bundle of wires detects cosmic rays about once a second imagine what cosmic rays must be doing to the rest of the astronauts' bodies.
Radiation and You
So you decided to live under a dome and swear off electrical devices. Are you avoiding radiation yet? No because there is no food you could eat on earth that isn't radioactive. You decide to freeze yourself to be woken up at some date in the future when food becomes 100% radiation free. How about then? Make sure they wake you up before too long or naturally existing radioactive isotopes in your body will do more damaged than can be repaired (you can't suspend the animation of nuclear chemistry).
The atomic weight of carbon 12 (thats the normal kind with 6 protons and 6 neutrons) is exactly 12. The rest of the atomic weights on the periodic table are based around that. So why is it that when I look at my periodic table I see an atomic weight of 12.011 listed for carbon?
The periodic table gives atomic weight of relative abundance of the elements in all their isotopes. The average atomic weight of any clump of carbon I pick up on earth is going to be 12.011.
Some quick back of the envelope math
1 - 12/12.011 = 0.0009
So 0.09% of all carbon on earth is something other than carbon 12 and probably radioactive. This applies especially to living beings such as ourselves.
Organisms digest and respirate so they are constantly recycling carbon. As long as an organism lives they maintain the same ratio of radioactive isotopes. When an organism dies those isotopes decay without the interference of chemistry or biology. Because the rates of decay are well known radio dating is used to determine how long something has been dead.
Particles come in all sorts of flavors. Generally though the kinds of particles you and I might be interested in are what are called baryonic matter. To non-particle physics baryonic matter is all the matter you will ever need to worry about. Non-baryonic matter includes such elusive concepts as photons, the purely theoretical Higgs boson (which suposedly gives the other particles mass), practically philosophical phonons (which are what happens when sounds collapse their wave state, whatever that means). Baryonic matter on the other hand is familiar stuff like protons, neutrons, electrons, antimatter and many more exotic particles. Most importantly to me baryonic matter particles actually tend occasionally act like particles rather than behaving like ripples is spacetime. Though baryonic particles may cause ripples in spacetime, they are almost never said to be ripples in spacetime. The same can not be said for non-baryonic particles.
So particle radiation is basically like a hail of very tiny very fast BB pellets.
Electric charge
Many type particle radiation consist of particles that have positive or negative electric charge. Alpha particles, beta particles and cosmic rays all have electric charge.
The atoms in your body, and most everyday substances, are said to be electrically neutral. This is only true when atoms are relatively small (nearly always). When we are talking about particles though, atoms are much much larger.
The atom is surrounded by a shell of negatively charged electroness. The nucleus on the other hand is a densely packed cluster of positively charged protons and electrically neutral neutrons. The whole thing is held together by forces that are beyond my (and most peoples) understanding.
The thing is though, while electrons might be electrically attracted to the nucleus something called Weak force (seriously look it up) prevents the electrons from colliding with the protons (though if that did happen charges would cancel and you would get a neutron, don't ask me how they know this). The electrons are only weakly connected to the nucleus. Like rebellious teenagers electrons can, and do, leave the atom if given the right influences.
Chemistry
Chemistry happens when electrons from one atom aren't content to stay with that atom but windup traveling with other atoms.
Covalent, or molecular bonds are when two atoms share electrons with each other. This is the strongest type of bond.
Metallic bonds are when electrons are shared throughout a large crystal structure of atoms. This is what makes metals are conductive.
Ions are atoms that are missing, or have an extra, electron and consequently carry electric charge. Ionic bonds are when one atom takes an electron from another atom to complete an eight electron shell (this is like a greedy stamp collector stealing your stamps to complete his set). This creates one negatively charged and one positively charged atom. The two consequently stick to each other. Ionic bonds dissociate in water.
Ionizing radiation
Imagine if you will, high speed charged particles reigning down on our placid molecularly bonded atoms. If the charged particle is moving slow enough they will actually bounce harmlessly off the atoms, possibly imparting momentum but in no way altering the atom or its relationships with nearby atoms. This is because even electrically neutral atoms have electrically charged parts.
Most of the time though the charged particle are moving very fast. As they zip along they ionize many atoms in or near their flight path. The high speed electric field strips atoms of their electrons. This usually destroys whatever chemistry might have been going on.
What once was a segment of DNA that told your cells how to make that unique hue of your eyes now says nothing, it has been ripped to shreds by ionizing radiation. You cell goes to work trying to repair the DNA, but this is like trying to reassemble documents after they have been to the shredder. Now the instruction seem to be telling the cell to reproduce ceaselessly and ignore all pleas from your body to stop.
Months later the descendents of this cell have now formed what is known as tumor. Before you die of cancer the doctors have a number of gambits they would like to try. One of these is to blast your tumor with radiation.
This may sound like fighting fire with gasoline but it actually makes sense. It was really a fluke that created the tumor in the first place. Blasting the same cells again would cause the DNA to say something else this time, assuming the cells don't die instantly which they would.
EM radiation can also be ionizing radiation. This hinges on frequency (wavelength) rather than total intensity.
Radioactive Decay
Certain configurations (actually most configurations out of whats possible) of protons and neutrons are intrinsically unstable. They can emit alpha, beta and gamma radiation until they reach a stable configuration.
Nucleons are the components of an atomic nucleus. You should probably know by now that these are protons and neutrons.
Mass number is the total number of nucleons. Uranium 235 has a mass number of 235 nucleons.
Atomic number is the number of protons. This determines chemical properties and what element an atom is.
An isotope has a specific atomic number and mass number. All uranium isotopes have the same atomic number but only Uranium-235 has a mass number of 235.
Decay Modes
Alpha decay is when an unstable (usually large) isotope gives up a helium size chunk of its nucleus in order to reach a more stable state. Alpha particles are just helium atoms that have no electrons and move at excessive speeds. Alpha decay reduces mass number by 4 and atomic number by 2.
Beta decay happens when nuclei have too many or too few neutrons. A neutron can release energy and form a proton and an electron. A proton can turn into a neutron by absorbing energy and releasing a positron. A positron is like an electron only with positive charge (actually its the anti-electron). Electrons and positrons are known collectively as beta particles. Beta particles are ejected from the nucleus at high speeds by the weak force. Beta decay will reduce or increase atomic number by 1 while conserving mass number. Beta particles have very little mass.
Gamma decay is just when the nucleus needs to release excess energy. Gamma rays are released but the nucleus does not need to change mass or atomic number to do this. Often gamma decay follows immediately after other decay modes that may have left the nucleus in an excited state.
A decay chain is the chain of radioactive unstable isotopes a nucleus will transition through until it reaches a non-radioactive stable isotope.
Half life is the amount of time it takes for statistically half of an isotope to decay into something else. Although some isotopes have half lives of millions of years, most decay in no time at all. The isotopes that stick around longer are more stable and less radioactive.
Gamma radiation is the most penetrating. It can go right through your skin and even your hazmat suit with no trouble. The best precaution is a nice thick layer of lead.
Beta and alpha radiation are less penetrating and simple rubber hazmat suit is ample protection. The danger with alpha and beta sources is contamination.
Nuclear Contamination
So you hear that the nuclear power plant is spilling nuclear radiation into the ground water. It must be having affect on peoples minds because they seem to think that the noun form of the verb radiate can somehow be a substance.
Can I spread intimidation on bread or sprinkle consternation on my flowerbed? No I can not.
Radioactive substances can leak. This is known as contamination. Nuclear contamination is scary because if it isn't handled properly a lot of people are going to get sick, the kind of sick you don't get better from.
Blowups happen. Your nuclear plant might only be designed to handle acts of god of certain magnitude. Something bigger could come along and screw things up. Though every safeguard may prevent it, sabotage or even simple negligence can conceivably cause contamination as well.
Though for every eventuality there is an SOP (standard operating procedure). There is reason for this. While it becomes increasingly expensive to protect a power plant from increasingly unlikely catastrophes it cost relatively little to run simulations and write documentation of steps to control the extent of damage is in those scenarios.
If you are unfortunate enough to be near a contamination there are steps that you can take that could conceivable prevent you from ever developing ill health effects.
Stay away from milk and dairy. Meat and fish are also dangerous. The goods already in your pantry before the spill as well as food from other non-contaminated areas should be totally safe.
Iodine pills keep iodine out. Your body doesn't "need" iodine to fight radiation. Rather iodine tablets clog your system with non radioactive iodine. This prevents radioactive iodine from being absorbed latter thereby averting thyroid cancer.
Listen to the authorities. They have a lot more training with this sort of thing than you.
When asked, evacuate. Evacuation is a good thing. It means that you are not already contaminated. If you get cancer later on in life its because you kept smoking cigarettes, you dumbass. Remember, as with any type of contamination the alternative to evacuation is quarantine.
Usually the worry with contamination is a chronic doses of radiation as the radiation lingers in a contaminated person for an extended period of time.
Neutron Radiation
Neutrons are not produced in nuclear decay and they carry no electric charge. The pass right through electron shells like they are not even there. They eventually slam into the nucleus and do numerous things to it. Adding a neutron increases mass number by 1. It also adds energy. The old isotopes may have been stable but the new one probably isn't. This causes it to transmute into new elements entirely.
Although neutron radiation does not ionize you can see why it is dangerous to people. It can make non radioactive materials radioactive without physically contaminating it. It can weaken strong materials by altering the elemental makeup.
Free moving neutrons are only created in nuclear fission and fusion reactions. Neutrons are actually a vital part of sustaining power generating nuclear reactions.
Neutron activation analysis is a really high tech way to measure exactly what and how much elements and isotopes something has. Scientist who need to radio date something like a fossil typically use x-ray spectrometry. Though x-ray spectrometers are relatively cheap and even portable there is a limit to their accuracy.
I had the privilege once of working as an intern at a research reactor. This reactor doesn't produce power. It only produces neutrons. It does so on demand for the sole purpose of neutron activation analysis. This reactor is incredibly safe. Nuclear meltdown is impossible.
Neutrino Radiation
Neutrinos like neutrons have no electrons and are also produced in nuclear reactions. Unlike neutrons and virtually every other type of radiation no amount of shielding in the world can stop the onslaught of neutrinos. Sounds dangerous right? Well no, not really.
Neutrinos interact very weakly with matter. So weakly in fact that neutrinos from the sun will often pass right through the planet earth entirely without so much as an atomic jostle. They have proven very difficult to detect.
Cosmic Rays
These are fragments of supernova or even weirder processes. Cosmic Rays are composed of heavy nuclei that are traveling close to the speed of light. They are quite hazardous to your health. They are bombarding the planet all the time. Metal shielding actually makes the problem worse because as the cosmic rays are slowed down by the atoms in the metal they release energy in the form of intense x-rays. This is called the bremsstrahlung or braking radiation.
Why are we surviving this onslaught? We aren't. The earth's magnetosphere actually deflects this stuff. Astronauts are not so immune. They have reported fireworks in their vision, even when they close their eyes. This is the result of cosmic rays striking their optic nerve. If just that bundle of wires detects cosmic rays about once a second imagine what cosmic rays must be doing to the rest of the astronauts' bodies.
Radiation and You
So you decided to live under a dome and swear off electrical devices. Are you avoiding radiation yet? No because there is no food you could eat on earth that isn't radioactive. You decide to freeze yourself to be woken up at some date in the future when food becomes 100% radiation free. How about then? Make sure they wake you up before too long or naturally existing radioactive isotopes in your body will do more damaged than can be repaired (you can't suspend the animation of nuclear chemistry).
The atomic weight of carbon 12 (thats the normal kind with 6 protons and 6 neutrons) is exactly 12. The rest of the atomic weights on the periodic table are based around that. So why is it that when I look at my periodic table I see an atomic weight of 12.011 listed for carbon?
The periodic table gives atomic weight of relative abundance of the elements in all their isotopes. The average atomic weight of any clump of carbon I pick up on earth is going to be 12.011.
Some quick back of the envelope math
1 - 12/12.011 = 0.0009
So 0.09% of all carbon on earth is something other than carbon 12 and probably radioactive. This applies especially to living beings such as ourselves.
Organisms digest and respirate so they are constantly recycling carbon. As long as an organism lives they maintain the same ratio of radioactive isotopes. When an organism dies those isotopes decay without the interference of chemistry or biology. Because the rates of decay are well known radio dating is used to determine how long something has been dead.
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