(Radiation and Geiger Counters) How to Separate Alpha, Beta, Gamma

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Background 38 CPM
Total 19,262 CPM *
Beta+Gamma 14,116 CPM *
Gamma 1,392 cpm *

* values shown minus background (e.g. 19300 CPM total becomes 19,262 CPM after 38 CPM removed)

This is how we figure it out:

Alpha = Total – Beta+Gamma
Beta = Beta+Gamma – Gamma
Gamma = Gamma

We can replace the words for real values from above:
Alpha = (19262 CPM) – (14116 CPM) = 5146 CPM
Beta = (14116 CPM) – (1392 CPM) = 12724 CPM
Gamma = (1392 CPM) = 1392 CPM

The results sum back to the total, which helps us check our work:
Alpha + Beta + Gamma = 5146 CPM + 12724 CPM + 1392 CPM = 19262 CPM
——————————————————————————————

Here’s that bit about the copper lol I added it for fun, but it is correct.
Sheilding HVL of Copper: 10.2 mm
Thickness of Sample: ~4mm
Most Common Energy of Gamma: 214Bi 609.31 keV at 44.8%
e^-log(2)4mm/10.2mm = 0.76199, where d/dx e^-((ln(2)/10.2mm)*x) = (4^((-2+x)/x) log(2))/x^2

Lasers! Lasers! Lasers!

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Lets learn about lasers!

Key Terms:
Lasing Medium / Gain Medium – The material which forms the laser light.
Pump – The energy source needed to induce the population inversion.
Population Inversion – The act of causing the electrons in the lasing medium to jump to higher energy states.
Meta-Stable – A short period of stability.
Stimulated Emission – When an electron drops to a ground state and emits a photon as a result of another photon passing by it. Both photons are coherent.
Spontaneous Emission – When an electron drops to a ground state and emits a photon after a short time in a meta stable state.

The lasers in the video are DPSS Lasers (Diode Pumped Solid State)

An Infrared Aluminum Gallium Arsenide diode laser emits 808nm photons. These pump a Neodymium-Doped Yttrium Orthovanadate or Neodymium-Doped YAG crystal which emits 1064nm laser light. This light is Freq doubled using Potassium Titanyl Phosphate crystal to become 532nm, a beautiful green color

=)

Simple Decay Equation – Example (Polonium 210)

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How to calculate the current activity of a source given the activity at one point, the time which has elapsed, and the decay constant.

Activity_now = Activity_then * e^-((ln2/halflife)*elapsed_time)

Now, enter into your calculator for activity of 1000Bq, halflife of 20min, and elapsed time of 40min:

1000 * e ^ – ( ( ln(2) / 20 ) * 40 ) )

☢ Radioactive Tc99m ☢

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Technetium 99m has a half life of 6.01 hours and transitions to normal Technetium 99 via the release of surplus energy in the form of a gamma photon at 140.21 keV

Statistically Valid Detections

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The basic idea comes from z-score * sqrt(2*background)