Gamma rays


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What are they?
Gamma rays (γ-rays) are electromagnetic waves with the smallest wavelengths in the electromagnetic spectrum.

Are they dangerous?
Gamma-ray detectors typically contain densely packed crystal blocks. As gamma rays pass through, they collide with electrons in the crystal. This process is called Compton scattering, when a gamma ray strikes an electron and loses energy. These collisions create charged particles that can be detected by the sensor.
Where do they come from?
Gamma rays come from stars, super novas, black holes and pulsars. They are also created on earth by natural radioactive decay, by nuclear explosions and by lightning in thunderstorms.

How do we detect them?
Unlike optical light and x-rays, gamma rays cannot be captured and reflected by mirrors. Gamma-ray wavelengths are so short that they can pass through the space within the atoms of a detector. Gamma-ray detectors typically contain densely packed crystal blocks. As gamma rays pass through, they collide with electrons in the crystal. This process is called Compton scattering, when a gamma ray strikes an electron and loses energy. These collisions create charged particles that can be detected by the sensor.

Compton Scattering
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What can they be used for?
Gamma rays can abe used to go through the skin to kill cells, such as cancerous cells. This can be used to cure some types of cancer. Gamma-induced molecular changes can also be used to alter the properties of semi-precious stones. Gamma rays can be used to detect for element of different planets.

Anything else interesting?
Gama rays can release more energy in 10 second than our sun emits in its entire 10 million years of expected lifetime. NASA's swift satellite recorded a gamma ray burst of an exploding star 13 billion light years away, it was among the most distant object ever detected.



In the table below, fill the cells with very brief notes. Use the other pages to gather the information from, and you may want to go outside of this wiki if you really can't find the information here (though I'd be surprised!).



Gamma
X-rays
UV
visible
IR
microwaves
radio
How are they generated?
Gamma rays come from stars, super novas, black holes and pulsars. They are also created on earth by natural radioactive decay, by nuclear explosions and by lightning in thunderstorms.
X-rays are generated by an X-ray tube, a vacuum tube that uses a high voltage to accelerate the electrons released by a hot cathode to a high speed, they can be produced many different ways to make different frequencies of wave that can be used to see through different objects. They are produced in parcels of energy called photons. They are also produced naturally by many objects in the universe, scientists use these to work out what far away objects are.
They can come from the sun, but you can get man made lamps for experimental perposes, tanning beds which produce ultra violet rays, just as the sun does.
Hot thingslumenecnt things
stars
photons
NOT THE MOON
William Herschel conducted an experiment measuring the difference in temperature between the colors in the visible spectrum. He placed thermometers within each color of the visible spectrum. The results showed an increase in temperature from blue to red. When he noticed an even warmer temperature measurement just beyond the red end of the visible spectrum, Herschel had discovered infrared light!
Microwaves are emitted from a number of sources, for instance, in a mobile phone, they are generated by a transmitter chip and an antenna,
while in a microwave oven they are generated by a 'magnetron'. They are also released as a form of electromagnetic radiation from large stars
Microwaves are emitted from a number of sources, for instance, in a mobile phone, they are generated by a transmitter chip and an antenna,
while in a microwave oven they are generated by a 'magnetron'. They are also released as a form of electromagnetic radiation from large stars.
Naturally occurring radio waves are made by lightning, or by astronomical objects.
Manmade radio waves are generated by a transmitter.
How are they detected?
Gamma-ray detectors typically contain densely packed crystal blocks. As gamma rays pass through, they collide with electrons in the crystal. This process is called Compton scattering, when a gamma ray strikes an electron and loses energy. These collisions create charged particles that can be detected by the sensor.
In hospitals the pictures were captured using image receptors such as thin films and photographic plates. Now they use computer technology to generate the images produced by X-Rays. Astronomers also use X-Rays, as these are absorbed by the earth's atmosphere they use balloons and satellites at very high altitudes. X-Rays can be indirectly sensed by humans but they cannot be seen by any human or animal eye.
To detect them you can simply use a filtrate this is the cheapest option and used frequently. As well as this you could use a UV dectector, they come in a range of styles and prices. As with most things, the more you pay the better the quality.
Our eyes
Our eyes cannot see infrared waves but instruments that can sense infrared energy — such as night-vision goggles or infrared cameras–allow us to "see" the infrared waves emitting from warm objects such as humans and animals.

Because humans cannot detect electromagnetic radiation we need special tools to detect them. If the waves are used for communications we use a reciver to detect them. If we are checking for contamination we can use a gieger tube to test for them.
Radio waves are detected by the use of radio telescopes.


How might they be dangerous?
Gamma-ray detectors typically contain densely packed crystal blocks. As gamma rays pass through, they collide with electrons in the crystal. This process is called Compton scattering, when a gamma ray strikes an electron and loses energy. These collisions create charged particles that can be detected by the sensor.
X- rays can damage cells and cause cause cell mutation which can cause cancer or cell death. It can cause these illnesses as it produces radiation as do lots of high frequency waves, this causes cells to behave differently and can have severe effects. Ironically X-Rays are also used to treat cancer, this treatment is called radiotherapy, it involves a very high amount of radio waves. People are X-Rayed fairly regularly and although the process is safer than it used to be there is still a relatively high risk of becoming ill as a side effect of the treatment.
It can be dangerous as they damage and kill cells. When this happens we ussually call it sun burn. This occurs when our skin has been exposed to the sun or due to a lack of sun cream, and the skin starts to redden, it can become sore, but usually leaves skin looking darker, described commonly as; tanned. But many of the cells have been killed in the skin, for the minority this could result in cancer.
Not dangerous at all.
Infrared waves are heat waves. If the cells absorb too much infrared radiation the heating will damage or kill the cells.
Infrared from the sun causes sunburn.
Prolonged exposure to microwaves is known to cause cataracts, which is a clouding of the lens, in your eyes preventing you from seeing clearly. Recent research indicates that microwaves from mobile phones can affect parts of your brain - after all, you're holding the transmitter right by your head. Although there is a feeling that you're more vulnerable if you're young and your brain is still growing.
It is believed that exposure to large doses of radio waves can result in disorders such as cancer. There are also claims that people who are exposed to the low frequency field that are caused by overhead cables are affected.
What are the main or most significant uses?
Gamma rays can abe used to go through the skin to kill cells, such as cancerous cells. This can be used to cure some types of cancer. Gamma-induced molecular changes can also be used to alter the properties of semi-precious stones. Gamma rays can be used to detect for element of different planets.
X- rays can be used to look at the internal structure of objects, they are often used in airport scanners as they can travel through fairly thick objects without being scattered or absorbed. This makes them very good at producing normally images of normally opaque objects, they can also be used to check for weak spots in metals. The idea of using X-Rays to see through human tissue was first formulated in 1895 in Germany. Dentists use them very often to get a more detailed image of the inside of the mouth, they can check for any chips or cavities much more easily than looking manually,especially right at the back of the mouth.
Ultra violet rays can be used for tanning, in a tanning bed or by the sun. Manhy people have suffered great damage from this and some have even developed cancer. For killing microbes, for this you use lamps; this would usualy be in a lab with protective gear so that no harm comes to anything, except the bacteria of corse.... killing other bacteria; identifying substances; the makeup of atoms; the energy levels of atoms, all of these would also more often than not be performed in a lab, by finding out info about the make up of atoms we can discover more about our world, and how we live, and why we live.
Seeingdisplaying info
lighting areas
Night vision goggles pick up the infrared light emitted by our skin and objects with heat.
-A remote control uses light waves just beyond the visible spectrum of light—to change channels on your TV.
-Infrared is also used for cooking in grills and toasters.
Microwaves cause water and fat molecules to vibrate, which makes the substances hot. Therefore we can use microwaves to cook many types of food. Mobile phones use microwaves, as they can be generated by a small antenna, which means that the phone doesn't need to be very big. The drawback is that, being small, they can't put out much power, and they also need a line of sight to the transmitter. Microwaves are also used by fixed traffic speed cameras, and for radar, which is used by aircraft, ships and weather forcasters. The most common type of radar works by sending out bursts of microwaves, detecting the "echoes" coming back from the objects they hit (like a bat uses echo location), and using the time it takes for the echoes to come back to work out how far away the object is. They are also used to transmit data over long distances with satelites.
Manmade radio waves have been used for a long time to send information, receive information, and to 'see' objects. Radar uses radio waves to 'see' distant objects by bouncing waves off an object and seeing how long it takes for the waves to return. Radar can even be used to find oil or see what chemicals are in soil. Radios also use these waves to send and receive information. Natural radio waves were first discovered in the 1930s by Karl Guthe Jansky, working for Bell Laboratories. Before his discovery, everyone thought only people could generate radio waves. Bell was detecting static on his radio channels, and had Jansky try to figure out where this static, or interference was coming from. Surprisingly, the interference was coming from space! This discovery eventually led astronomers to look at radio waves along with optical waves to find things in the sky. These radio astronomers use giant Radio telescopes, shaped like satellite dishes, to gather and analyze the waves. Radio waves are used for many things today. They broadcast radio and television, communicate with satellites, let mobile phones communicate with each other, make radar systems, and allow computers to share information without wires.

I may have not read the instruction that said 'very brief notes'!!!!

Very good work indeed. Comprehensive and well presented.

Grade A, and a merit.

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