Page 75 - Astounding Pulp V2

ASTOuNDING SC_ENCE-FICT ION
I
TRA NS. I UTATJON, J 39 75
ing it again and immediately putting it collision is exactly head-on, which is
near the counter. which hroke out into a rare occurrence in nucleur phenomena, xw +i.
a terrific clatter of activity from all the too. And you can't put '·english" on a (4) z xw + H2 1. H1. + 2
electrons emitted by n uclei undergoing neutron. Thus within the bucket of l. l yW+i. + e
this last r eaction. No really conclusive water or paraffin the neutrons are slowed .... Z+ ::i. - 1.
proof that t he elen1ent was cadmium, down, and their probability of capture •
but there's ha1-d ly t ime for that in a lec- by a silver nucleus is correspondingly Pr oton· Bombardment
t ure. And a nyway, we have already increased, just as it is easier-for me,
'W
done t hat experimen t, ,and know that at least- to catch a slow grounder than {5) X + I H1 = hv + Z+l. yW+1
it's cadmium, a nd the freshmen were a hot line drive. z l. XW+1. +
• w illing to t rust us. I "T ,. e
► Z,
I called the bucket of water m my So F AR we have discussed some three
recipe a " philosophe r's stone" ; it was possible transmutation reactions; the ex- Neutron Bombardme nt
d iscovered in O ctober, 1-934, by F ermi. ample of the second happened to pro- W- 3
U p to that t ime the neut ron sou rce and duce an isotope of the original element ( 6) xw + n1. - 2 He* + z-2 V
silver had merely been brought close as the end product, but the same reac- :t 0 I w W- 3 + e
together; F ermi obser ved that a tre- tion holds good fo r other elements ~ -~
z - 1
mendous increase in the activation. of where the next higher isotope-the un- (7) · xw .. WW
silver took p lace when the neutron source stable one in the carbon-bornbarded- n1 ::: l. H-i + z -1. ..
a nd silver w ere surrnunded by quanti- with-deutons case-is actually stable, ~ 0 I ►- zX w e
~ies of water or paraffi n. This effect and this reaction also leads to the pro- - 1
1s broug h t a bout simply by the slowing d uction of a new element. There are h'V + XW+1
of the neutr ons from collisions with the in all some eight general reactions whiah ( 8) xw + 0 nl z
h7 drogen nuclei of the water or paraffin, have been fairly well investigated th~t z I W+1. + e
either wax or oil. lead to the production of radioactive 9"- 2 +1.y -1
. As a ny billiard player k nows, on the products and different elements, and it
impa~t of two equally heavy balls the w?uld be verbose to discuss each in de- are startina with the reaction. But this particular i~otopc j-
~ r st 1s slowed d own, imparting some of tad. Instead, we may summarize them In all cases ,~e . aht be no~ed that in unstablc, too, and it would also dee.: •_m -
its momen tum to the second unless -the all by giving the reactions · in implicit element X , and it 1111 "' lJ) ,v,.th a pb ·e, probably to giYe us ;; 0 ~ 11 11 1 , ,vh1ch
n otation, as follows: some of the process e ::, • we enc 1 t •
1
. f the same element, ot 1e1 is a stable, known isotope.
new isotope o A d . . c·l-e"' H ow _much do w e make by tlic:;e
] ]1 a
•
tunes a! new element. ]1 11 C::, ~
t . ue fu rther than methods ? Very little. .'\s yet. 1w o ne
Alpha Pa~tic le Bomba~d~ent the process may. con_ m . . . has produced wcighable q~1a1~tities o_i a
t o i·eacuons it by chance
.
{ 1) I t 1e given w ' transmuted element, but 1t 1s p os:.-1ble
+ He 4 - · n1 the final Jroduct happens to be an un-
. tl e If 011 the other hand the
2 0 + z+:a zW+3 sta i I J e 1s0 op • . . • _ that prnduction oi 1·a<lioact i,·e St)dium
.
L zw+3 + fi rst pro( uc ·t foi·ined is a stable 1::.otope, from magnesium with the cyclat ron at
· 1~1
I
Berkeley will make enough t o m ake it
a stop at once.
.
ius,
.
----i►-. Z+1 + 1. 8 the react~on 1~1 y . 1 (8) to cadmium, possible to actually measu re by physical
(2) r-i1 . on applymg i eact101 . . 106 108 means the amount of neon procluc.:cd on
+ + . 1 t ble isotopes , ,
·
1 which has tie s a 1 i4 115 and 116 its disintegration. O ur little lectu1e ex-
110 , l ll, 112 1 3 'Jarti~ular aton~ periment required about $.1.._50 wor th ·t
• ! '
if the neutron hill any I · d
l
except the first two or the_ ast on:-an radon, and in the two tv-,enty-second
exposures to the neutron source ,vc
all three of these are rar~ m natm e~~he
Deuton Bombardment process stops a t O nce with the e1111::,::,ion made about 6.000,000 cadmium atom s.
.
• d.. . 1·11dicated in the equation. T hat is 0.00000000000000112 g rnms o f
(.J) I o ra 1at1011 as • cadmium-not much for $150 !
1
n1. + H, on the other hand, the neutron . ~,t~
0 say the 116 isotope, the unS t able 117 J::,O T hese low yields a re simply a m atter
of geometry and marl~s111a1}ship; thus
tope would be produced, decon~pose, and
111 accordina to the if a proton or deuton 1s bemg u sed to
we would have 1!l I n , "'