Forest Scintillators - Revision history

Oborn: /* Benzene/Toluene */

2010-01-08T19:46:25Z

Benzene/Toluene

2010-01-08T19:45:58Z

Benzene/Toluene

2010-01-08T19:45:27Z

Benzene/Toluene

2009-06-19T16:34:57Z

In-organic scintillators

2009-06-19T16:34:20Z

2008-06-09T18:56:53Z

Benzene/Toluene

2008-06-09T18:53:47Z

Benzene/Toluene

2008-06-09T17:31:30Z

In-organic scintillators

2008-06-09T17:30:41Z

In-organic scintillators

2008-06-09T15:37:29Z

@@ Line 31: / Line 31: @@
 Benzene, and it's less toxic cousin Toluene, is the magic material for producing scintillation light.  The electrons on a Benzene ring are so loosely bound (de-localized) that they do not feel atomic collisions.
-[[Image:Forest_Detectors_BenzeneRing.jpg]][[Image:Forest_Detectors_BenzeneRing.gif]][[Image:Forest_Detectors_BenzeneRing1.jpg]]
+[[Image:Forest_Detectors_BenzeneRing.jpg]][[Image:Forest_Detectors_BenzeneRing.gif]][[Image:Forest_Detectors_BenzeneRing1.jpg|200 px]]
 ==Vibration state==

@@ Line 31: / Line 31: @@
 Benzene, and it's less toxic cousin Toluene, is the magic material for producing scintillation light.  The electrons on a Benzene ring are so loosely bound (de-localized) that they do not feel atomic collisions.
-[[Image:Forest_Detectors_BenzeneRing.jpg]][[Image:Forest_Detectors_BenzeneRing.gif]][[Image:Forest_Detectors_BenzeneRing1.gif]]
+[[Image:Forest_Detectors_BenzeneRing.jpg]][[Image:Forest_Detectors_BenzeneRing.gif]][[Image:Forest_Detectors_BenzeneRing1.jpg]]
 ==Vibration state==

@@ Line 31: / Line 31: @@
 Benzene, and it's less toxic cousin Toluene, is the magic material for producing scintillation light.  The electrons on a Benzene ring are so loosely bound (de-localized) that they do not feel atomic collisions.
-[[Image:Forest_Detectors_BenzeneRing.jpg]][[Image:Forest_Detectors_BenzeneRing.gif]]
+[[Image:Forest_Detectors_BenzeneRing.jpg]][[Image:Forest_Detectors_BenzeneRing.gif]][[Image:Forest_Detectors_BenzeneRing1.gif]]
 ==Vibration state==

← Older revision		Revision as of 16:34, 19 June 2009
Line 58:		Line 58:


−	[http://~~www~~.iac.isu.edu~~/mediawiki~~/index.php/Forest_Detectors Go Back]	+	[http://wiki.iac.isu.edu/index.php/Forest_Detectors Go Back]

← Older revision		Revision as of 16:34, 19 June 2009
Line 4:		Line 4:
	In general, most materials are capable of scintillating.		In general, most materials are capable of scintillating.

−	It takes about 10^{-9} s ( 1 ns) for an atom to de-excite by giving off light. Atoms can , however, loose there energy by colliding with other atoms. Atoms which collide on time scales less than 1 ns could loose their energy via the collision instead of through the emmission of light.	+	It takes about <math>10^{-9}</math> s ( 1 ns) for an atom to de-excite by giving off light. Atoms can , however, loose there energy by colliding with other atoms. Atoms which collide on time scales less than 1 ns could loose their energy via the collision instead of through the emmission of light.

← Older revision		Revision as of 18:53, 9 June 2008
Line 31:		Line 31:
	Benzene, and it's less toxic cousin Toluene, is the magic material for producing scintillation light. The electrons on a Benzene ring are so loosely bound (de-localized) that they do not feel atomic collisions.		Benzene, and it's less toxic cousin Toluene, is the magic material for producing scintillation light. The electrons on a Benzene ring are so loosely bound (de-localized) that they do not feel atomic collisions.

		+	[[Image:Forest_Detectors_BenzeneRing.jpg]]

	==Vibration state==		==Vibration state==

← Older revision		Revision as of 17:31, 9 June 2008
Line 54:		Line 54:

	If you mix in some Thalium (dopant), then the electron-hole (hole halide) ion will more readily get trapped by the Thalium and emitt light.		If you mix in some Thalium (dopant), then the electron-hole (hole halide) ion will more readily get trapped by the Thalium and emitt light.
		+
		+
		+
		+	[http://www.iac.isu.edu/mediawiki/index.php/Forest_Detectors Go Back]

← Older revision		Revision as of 17:30, 9 June 2008
Line 38:		Line 38:
	=In-organic scintillators=		=In-organic scintillators=

−	While organic scintillators rely on de-localize \pi-orbitals to emmit light, Inorganic scintillators rely on the electronic band structure of crystals.	+	While organic scintillators rely on de-localize <math>\pi</math>-orbitals to emmit light, Inorganic scintillators rely on the electronic band structure of crystals. The physical process involves the creation of electron - hole pairs to create light.
		+
		+
		+	NaI is an example of such a scintillator.
		+
		+	The Na in the crystal has a 3S electron conduction band
		+
		+	The I in the crystal has a 5P hole valence band
		+
		+	If you deposit 5.8 eV into the crystal you create a electron-hole pair which can then recombine and emitt the energy in the form of light.
		+
		+	The catch is that this only happens if the temperature is less than 300 K, otherwise the energy from recombination will go into vibrational (phonon) energy.
		+
		+	This means that pure NaI is a bad scintillator at room temperature.
		+
		+	If you mix in some Thalium (dopant), then the electron-hole (hole halide) ion will more readily get trapped by the Thalium and emitt light.

@@ Line 26: / Line 26: @@
 An atom in a solid can collide with 10 other atoms before loosing energy by emmitting a photon.
-=Benzene/Toluene=
+=Organic Scintillators=
 Benzene, and it's less toxic cousin Toluene, is the magic material for producing scintillation light.  The electrons on a Benzene ring are so loosely bound (de-localized) that they do not feel atomic collisions.
-=Vibration state=
+==Vibration state==
 Having the atom de-excite through the emission of photons is just half of the problem.  Getting the photons out of the material to a photon detector is the last half of the problem.  Fortunately , there are vibrational states which allows atom to de-excite produce photons which are not able to excite the next Benzene ring the pass by.  This makes the material transparent to the scintillation light.