Re: Neutron Flux Density Conversion (Cf-252)

[Hector Rene Vega Carrillo <rvega@cantera.reduaz.mx>]

At 03:16 PM 9/4/96 -0500, you wrote:
>Hi RADSAFERs,
>
>        This may not be feasible, but...
>
>        One of our researchers wants to know if the dose rate on our Neutron
>Dosimeter (NIST calibrated for Cf-252 and reads out in REM) can be converted
>to a Neutron Flux Density.  Does anyone have any ideas on this one?

        You might use the neutron-flux-to-dose-convertion factors for Cf-252.
        To the best of my knowlegde this factor, for bare Cf-252 neutron 
        source is: 
        Kerma = 3.05E(-11) Gy-cm^2/neutron
        Dose equivalenet = 34.2 Sv-cm^2/neutron
This numbers were obtained from: Griffith, R.V. et al: Compendium of neutron
spectra and detector responses for radiation radiation protection purposes, 
Tech. Rep. Series No. 318, IAEA, 1990.

Other source that you might use in the future is:
Vega-Carrillo, H.R.: Neutron field characterization in the vicinity of a
PET Cyclotron, PhD Dissertation, The University of Texas at Austin, 1995.

        Just recall that any of those factor can be obtained through
   
        Kerma = Integral[Rk(E) F(E)]
        D. Eq = Integral[RDE(E) F(E)]

here Rk(E) is the response function of your dosimeter to neutrons of energy E,
RDE(E) is the response function of your dosimeter to neutrons of energy E, and
F(E) is the neutron source, Cf-252, neutron energy flux (Energy spectrum).

>        I think they're trying to avoid purchasing another instrument and
>want to use our data.
>
>

Hector


-----------------------------------------------------
Hector Rene Vega Carrillo
Centro Regional de Estudios Nucleares
de la Universidad Autonoma de Zacatecas
C. Cipres 10, Fracc. La Penuela
98068 Zacatecas, Zac. 
Mexico

Phone/FAX: (492) 2 70 43
e-mail: rvega@cantera.reduaz.mx
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