bombing Now what?
Once we have our source and our moderator, it is more likely to want to produce radioisotopes. Of course, we will not go bombing the first thing that caught without knowing that we isotopes.
So here I leave this guide for you to know that bomb.
Note: due to the limited power of the neutron source, we do not get to create big deal. For this reason and to verify the presence of radioisotopes, I recommend using a radiation detector.
First all, we must use is recommended to be a pure element. For example, a piece of lead, a bismuth ore, or anything else that you have purchased online.
Here we just take a piece of pure lead, easy to find (an old pipe, usually of lead, for example).
Well, now the first thing to know is: how many isotopes of lead exist in nature.
For that matter both of webelements , and once there we go to the command element that we have. In the case of lead is Pb . Now for the left column, where it says Nuclear Properties -> Naturally Occurring isotopes. So, since we know all the isotopes of lead exist in nature. Just as a curiosity, the Pb-204 that occurs in 1.4% is radioactive, but due to its long half-life, its radioactivity is negligible, also in part because lead blocks radiation.
We see that the Pb-208 is the most abundant (52.4%), does this mean? Means that all the atoms that bombard the 52.4% (approx.) shall Pb-208.
22.1% of Pb-207, 24.1% Pb-206 and 1.4% Pb-204, which is now radioactive and can be activated even neutron, no problems.
When we introduce a neutron in an atom, which is what we do, the atomic number goes up 1 (n = +1). And if you noticed, in the naturally occurring isotopes, three consecutive, Lead 206, 207 and 208, these three are stable.
If the Pb-206 bomb, this is Pb-207, which is stable.
If the Pb-207 bomb, you will be Pb-208, which will be stable.
words, only create new isotopes are unstable and Pb-205 Pb-209, neutron activation pro-204 Pb and Pb-208.Entre the two add up to 53.8% of abundance. Only 53.8% of the atoms are bombarded nuesvos unstable isotopes. A pity, but good.
The moment of truth: we put our piece of lead in the moderator, and leave it a while to get it started, except that you have a source of Cf-252, which in a minute everything will have become Lead radioactive as the single.
So in putting it off (at least 10 minutes), we think, is being created and Pb-205 Pb-209, how are their characteristics?
Well now go back to the left column, under natural isotopes, where it says Radioisotopes. Yes, I know it does not leave the Pb-209, is that they have forgotten to put it. You can find it here out where all the isotopes of all elements (known, of course).
Now we know that Pb-209 decays by beta decay - with a half life of about 3 h, and Lead-205 has a life of 1.53e7 years.
This means that as the Pb-205 activity has a very long, almost all radiation detected by our dosimeters come from the Pb-209.
OK, we've been 10 minutes, one hour, one year, or the time given us the desire bombing.
Now take it out and measure radiation. How to know if indeed almost all come from Pb-209? Quite simply, we make a table and pointing the CPM that gives us the lead. We'll see how in about 3 hours the radiation has dropped to half in 6 to one quarter (this is easier to see if we have a powerful neutron source, or as I said we have many sources of neutrons, the more the better).
There, that's all. If you want to bombard with neutrons other item, follow these steps to see to believe and whether or isotopes are created these by measuring the half-life.
Other:
First, I must say that I have chosen the Lead is not only common, but because with him there are many cases, several isotopes in different proportions, one of them radioactive, only served us at the end of an isotope to detect the radiation,. As you can
view, not form many different isotopes Lead serves well to protect against neutron radiation, but used many Boron and cadmium to absorb neutrons.
I remember that the more moderated useis better, yours is less thermal neutrons or epithermal.
And nothing, now write some activations curious as Lithium.
Salu2!
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