M. Járó - L. Költő szerk.: Archaeometrical research in Hungary (Budapest, 1988)

Analysis - BALLA Márta, BÉRCZI János, KEÖMLEY Gábor, ROSNER Gyula, GABLER Dénes: Provenance studies of ceramics by neutron actiwtion analysis

(*th • oo + <V I

o)N

Av • m • fj A = M where

. c^th _ flux of thermal neutrons cr

0 - cross section of activation by thermal neutrons <î>

e - flux of epithermal neutrons Io - resonance integral (a factor expressing the probability of the activation by epithermal neutrons) N\y - Avogadro number m — mass of irradiated element fj - isotope abundance S — saturation factor S = l -exp(-Xtirr) D - decay factor D = exp (-Xt

c

) X - decay constant . In2 A = Ti/2 Ti/2 — half life M - atomic weight of irradiated element The relationship between the number of impulses, I produced by gamma photons with absolute abudance, fy (with emitted energy E-y) per unit of time in the detector of efficiency, e and the activity, A is ï = e • fy • A On the other hand: i = N/C, where N is the total energy peak generated in the gamma spectrum during measuring time, t

m and C = 1 - exp (-X • t

m

) Y is the so called measuring time factor which corrects for the decays occurring during the measuring time. The total energy peak area of the sample irradiated for time tj

rr

, cooled for time t

c and measured for time t

m is the following (obtained from the previous equations): N- (

*th' PQ + VMNAV- m-fje-fy s d c M Rearranging the equation: N (ftth g

o + ^e' *o ) N

Av' f

i

'

e •

i

y SDCm

= M