Difference between revisions of "ArCO2 IonizationPhysics"
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(New page: <math>\bar{E}=</math> 27 eV = average energy to ionize and electron in an Argon Atom <math>\bar{N_{PE}} = \frac{E_{\gamma}}{27 eV} =</math> average number of photoelectrons produced) |
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<math>\bar{E}=</math> 27 eV = average energy to ionize and electron in an Argon Atom | <math>\bar{E}=</math> 27 eV = average energy to ionize and electron in an Argon Atom | ||
<math>\bar{N_{PE}} = \frac{E_{\gamma}}{27 eV} =</math> average number of photoelectrons produced | <math>\bar{N_{PE}} = \frac{E_{\gamma}}{27 eV} =</math> average number of photoelectrons produced | ||
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| + | Quenching Gas: | ||
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| + | 1.) reduces the influence of the positive ions creates on the photoelectron signal: The excited Ar+ atoms emit photon in the UV range which are absorbed by the quenching gas | ||
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| + | 2.)Collisions with the quenching gas will neutralize the Ar+ ions. When the quenched gas, having an electron remove by the Ar+ collision, reaches the cathode and collects an electron, most of the energy goes into dissociation of the Quench gas. | ||
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| + | If the quech gas is CH4 then | ||
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| + | CH4+ <math>\Rightarrow</math> H2 + CH2 | ||
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| + | ;Argon Escape peak: | ||
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| + | :You need 3.2 keV to ionize a K-shell electron in Argon. If your incident ionizing particle (Photon or electron) has more than that energy then it is possible to excite Argon so it becomes a source of photons during the ionization process. If that photon ESCAPEs the detector without causing ionization, then your signal will be contain less ionized electrons. | ||
Revision as of 02:51, 19 December 2008
27 eV = average energy to ionize and electron in an Argon Atom
average number of photoelectrons produced
Quenching Gas:
1.) reduces the influence of the positive ions creates on the photoelectron signal: The excited Ar+ atoms emit photon in the UV range which are absorbed by the quenching gas
2.)Collisions with the quenching gas will neutralize the Ar+ ions. When the quenched gas, having an electron remove by the Ar+ collision, reaches the cathode and collects an electron, most of the energy goes into dissociation of the Quench gas.
If the quech gas is CH4 then
CH4+ H2 + CH2
- Argon Escape peak
- You need 3.2 keV to ionize a K-shell electron in Argon. If your incident ionizing particle (Photon or electron) has more than that energy then it is possible to excite Argon so it becomes a source of photons during the ionization process. If that photon ESCAPEs the detector without causing ionization, then your signal will be contain less ionized electrons.