Term
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Definition
| The SI derived unit of force. |
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Term
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Definition
| SI unit of work. One joule of work is performed when a force of one newton is exerted through a distance of one meter |
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Term
| How is work related to energy |
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Definition
| Energy is the capacity to do work |
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Term
| On the periodic table, what are rows called what are columns or vertical sections called |
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Definition
| Rows are called periods and columns are called groups or families |
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Term
| What are the four forms of energy |
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Definition
| Kinetic, Potential, Thermal, Chemical. |
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Definition
| A force acting through a distance |
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Term
| How many elements are there |
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Definition
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Term
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Definition
| property of certain nuclides to spontaneously emit radiation |
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Term
| What is radioactive decay |
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Definition
| The process by which nucleus spontaneously disintegrates or transformed by one or more discrete energy steps until a stable state is reached |
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Term
| What is the diameter of an atom |
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Definition
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Term
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Definition
| the total masses of the protons neutrons and electrons, and is based on carbon 12 it is also used to calculate the mass defect, so that the binding energy can also be calculated |
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Definition
| same atomic number but different mass number |
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Term
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Definition
| same mass number but different atomic number |
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Term
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Definition
| protons and neutrons in the nucleus |
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Term
| What is an alpha particle and where do they come from |
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Definition
| a charged particle that originates in the nucleus. it consists of 2 protons and 2 neutrons. It has a plus 2 charge and 4-5 MeV. with alpha decay the daughter will have a decrease in amass of 4. and atomic number by 2. mostly seen in heavy nuclides |
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Term
| what is beta and where do they come from |
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Definition
| they are a charged particle originating in the nucleus. they equal in mass and charge to an electron and are fission products. |
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Term
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Definition
| electromagnetic radiation that originates in the nucleus. photon energy of 3 MeC range. usually seen in particle emission. no mass or charge and travels at speed of light. It interacts with atoms to produce ionization |
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Term
| How do gamma rays differ from X-rays |
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Definition
| Xrays originate outside the nucleus and the gamma originates from inside the nucleus |
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Term
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Definition
| by a given time one of the the atoms of a given isotope has be transformed or decay |
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Term
| describe 3 photons interactions processes and the energy levels at which they occur |
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Definition
Photoelectric effect: all or none energy loss. photon gibes all it energy to orbital electron this is in the form of kinetic energy. <1MeV
Compton scatter: partial energy loss when only part of the energy transferred to an eleectron. Photon energies 200Kev to 5 MeV
Pair Production:All energy is converted to mass. impossible unless gamma ray has an energy level is greater than than 1.022 MeV. Positive particle goes on to encounter an anti particle and they both are annihilation |
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Term
| What is the difference between elastic and inelastic scatter |
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Definition
| elastic scatter a neutron hits an atoms nucleus and transfers some of its energy to the nucleus, so as to cause it to recoil off. Where inelastic is the incoming neutron dissipates into the nucleus and then is kicked out with a reduced energy, The nucleus also gibes up a gamma ray photon |
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Term
| Describe what happens in fission products |
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Definition
| It is the splitting of the nucleus into at least two smaller nuclei with an accompanying release of energy. |
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Term
| Define rad rem, and roentgen |
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Definition
Rad: measure of radiation abosrbed dose, defined as 100ergs of energy deposited in one gram of any material.
REM, unit of biological equivalent dose. it is the biological damage to tissue as 1 roentgen. Roentgen equivalent man. rem=rad*Wr
Roentgen. Is the measure of exposure, which is the ability of photons to produce ionization in air. sum of charge per unit mass of air. 2.58e^-4 coulombs/kg air. applies to gamma and xrays |
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Term
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Definition
SI unit of rem is sievert. 1 sv equals 100 rem
si unit of Rad is Gray. one Gy equals 100 rad, also applies to any material. |
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Term
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Definition
| it is aunit that measure the radioactivity of atoms. it is based on one gram of Radon-26. one curie is equal to 3.7e^10 dps 2.22e^12dpm |
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Term
| Define the decay constant |
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Definition
| is is the ln(2)/halflife of a nuclide |
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Term
| What are ionization, excitation, bremsstralung |
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Definition
Ionization is whe one or more eleectrons are stripped from their bound orbits results in an ion pair
Excitation is any process that adds enough energy to an electron of an atom so that it moves to a higher energy state. atom stay nuetrally charged. coulomb force
Bremsstralung: ovvurs when a beta particle comes close to the nucleus and the forces of the nucleus slow the particle downThis results in an emisson of x ray and areduced energy beta particle. |
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Term
| What is direct ionization |
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Definition
| uses the coulomb forces for ionizing radiation. no actual contact is made between particles and an atom, applies to alpha and beta |
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Term
| What is indirect ionization |
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Definition
| uses contact to produce ionization. applies to gamma, x-ray and neutrons |
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Term
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Definition
| it is the strong electrostatic force in the nucleus of like charged particles, acts over a long range |
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Term
| Define linear energy transplant |
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Definition
| average value of energy locally deposited by a charged particle in an absorbing medium per unit distance. |
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Term
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Definition
| Radiation weighting factor conversion used to derive the equivalent dose from the absorbed dose |
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Term
| How do you calculate dose equivalence |
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Definition
| it is calculated by times the absorbed average over the tissue or organ by the radiation weighting factor for a given typ or radiation Equation H=DtWt H=dose absorbed D=absorbed dose in radiation type W=radiation weighting factor |
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Term
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Definition
| The average energy lost by a charged particle per unit distance traveled |
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Term
| What is specific ionization |
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Definition
| The average number of ion pairs produced by a charged particle per unit distance traveled in an absorbing medium |
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Term
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Definition
| Average amount of energy needed to produce an ion pair in a given medium. This would apply to all types of radiation both particles and electromagnetic rays. |
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Term
| What is the mass energy relationship |
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Definition
| energy and mass can be converted into each other. and is demonstrated by E=mc^2 |
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Term
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Definition
| the total mass of the indicidual particle ofan atom (neutrons,proton,electrons) minus the mass of the atom as a whole. It is measured in AMU. used to calculate mass to energy conversion. |
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Term
| how does mass defect relate to binding energy |
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Definition
| represents the amount of energy that the mass that has been converted to energy which is needed to he bind the nucleus together |
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Term
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Definition
| energy required to drive the nucleus to the point of separation or splitting in half. the result is fission |
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Term
| What radioactive decay and how does it work |
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Definition
| It starts with a parent who is radioactive which decays to a daughter who is less radioactive |
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Term
| What is the difference between dose and exposure |
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Definition
| Exposure is the amount of radiation deposited in the air, whereas dose is the amount deposited in a medium |
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Term
| What are the three parts of the cell |
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Definition
| membrane , nucleus, cytoplasm. |
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Term
| What is DNA and how is it affected by radiation |
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Definition
| It is the master blueprint for the cell and for a cell to survive it must have its entire DNA. The major effects of radiation is that it inhibits DNA replication |
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Term
| how many RADS are required to rupture the cell |
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Definition
| 3,000-5,000 rads of absorbed dose will rupture the cell |
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Term
| What is the Law of Bergonie and Tribondeau |
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Definition
| "the radio-sensitivity of a tissue is DIRECTLY proportional to its reproductive capacity and INVERSELY proportional to its degree of differentiation(how specialized it is" |
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Term
| What are the 4 most radiosensitive tissues |
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Definition
Germinal (reproductive_ cells of the ovary and testis
Hematopoietic ( blood forming) tissues, red bone marrow, spleen , lymph nodes, thymus. Basal cells of the skin
Epithelium of the gastrointestinal track |
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Term
| What are the 4 most radio resistance tissues |
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Definition
| Bone, liver, Kidney and cartilage . |
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Term
| Discuss the difference between primary and secondary effects |
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Definition
| Ionizing radiation produces damage to cells but in a mostly nonspecific way. This means that other physical and chemical substances cause the same effects because the body responds to certain cell damage in the same way regardless of the cause |
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Term
| What is a free radical and how does it effect the cell |
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Definition
| When radiation passes through living cells it will directly ionize or excite atoms. This affects the forces that bind the atoms together in a molecule. if the molecule breaks up the fragments are called free radicals and ions, and are not stable. Free radicals are very reactive chemically and can combine other cells material and cause direct or indirect damage to cells. |
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Term
| Define stochastic effects and discuss how they effect the population |
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Definition
| Those effects in which the probability within a population of the effect occurring increases with dose, without threshold. this is to say that any dose might cause damage. |
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Term
| Discuss non-stochastic effects |
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Definition
| This is where the severity of the effect varies with the dose, and a threshold does exist. if a dose is kept below threshold the effect will not be observed. |
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Term
| IS there a threshold for for observation of radiation effects. |
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Definition
10-25rem
below this wont expect to see effects (deterministic effects) |
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Term
| What is lethal dose and how much is it |
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Definition
| It is the dose expectant to cause death. LD50/30 means that within 30 days 50% of the people exposed will die without proper medical treatment. |
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Term
| What is the difference between chronic and acute radiation exposure |
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Definition
Chronic is a low dose over a relatively long period of time
Acute is is a large dose of radiation over a short time period |
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Term
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Definition
| in excitation detectors, it detects when atoms give off the excess energy in the form of visible light |
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Term
| what type of instrument do you use for a contamination survery |
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Definition
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Term
| Discus semi conductor use as radiation detectors |
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Definition
| it is able to detect electrons as they move to a higher state |
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Term
| how do you detect fast neutrons |
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Definition
| thermalization and proton recoil |
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Term
| how do you detect thermal neutrons |
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Definition
| activation foils, boron activation, fission chambers, scintillation, thermoluminescence |
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Term
| What are the advantages and disadvantages of using a pancake probe (Ludlem 3A) |
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Definition
Advantages include cost, good for serface contamination and monitoring alpha beta, gamma or xrays.
Disadvantages not very effective for low energy beta radiation or identifying isotopes. |
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Term
| How do you calculate DPM from a scalar |
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Definition
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Term
| How does a scintillator work |
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Definition
| it measures radiation by analyzing the effects of excitation of the detector material by the incident radiation |
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Term
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Definition
| the time from the initial measure pulse until another pulse can be measured by the electronics |
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Term
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Definition
| the time from the initial full size pulse to the next full size pulse produced by the detector |
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Term
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Definition
| the time from the initial pulse to another pulse can be produced by the detector |
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Term
| Which instrument should be used to measure dose rate |
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Definition
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Term
| Describe the advantages and disadvantages of a NaL detector |
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Definition
Have the ability to discriminate between radiation types. and different energy levels.has high gamma sensitivity, has extreme low level energy response, best alpha detector
Its not good for beta or alpha response, poor low energy gamma response cumbersome, solution is one time use. requires regular power supply |
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Term
| Describe the advantages and disadvantages of a GeLi detector |
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Definition
| independent of pressure and temperatures effects, require less highly regulated power supply. are more sensitive to low energy and low intensity radiations. are not used to measure true dose and have large recovery times. |
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Term
| What is the best scintillation material for detection of alpha partices and gamma rays |
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Definition
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Term
| Define and discuss the ion pairs versus high voltage curve |
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Definition
| Ion pars must be collected in order to produce an output pulse or current flow from the detector. If a voltage potential applied across the electrodes a field is created in the detectors and the ion pairs will be accelerated towards the electrodes |
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Term
| how many volts does it take to create an ion pair? what are the typical W values for a gas detector? |
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Definition
| It takes 34eV to create an ion pair, typical W values for gas detectors are 25-50eV |
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Term
| What factors affect ion par production in a radiation detector |
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Definition
| the size and shape of the detector, pressure and composition of the gas. size of the voltage potential across the electrodes, the material of construction. the type of radiation, quantity of radiation. the energy of the radiation. |
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Term
| What are the physical discrimination and electronic discrimination and how are they used in radiation detections |
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Definition
Physical are a shielding and detector gas fill
electronic measures the pulse heights |
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