**1. NAME AND TITLE**

ZYLIND: An Interactive Point Kernel Program For Photon Dose Rate Prediction of Cylindrical Source/Shield Arrangements

**2. CONTRIBUTOR**

Wissenschaftlich-Technische Ingenieurberatung GmbH, Germany

**3. CODING LANGUAGE AND COMPUTER**

Fortran 77; IBM PC.

**4. NATURE OF PROBLEM SOLVED**

The program ZYLIND is an interactive point kernel program for photon dose rate prediction of a homogeneous cylindrical source shielded by cylindrical (radial) or plane (axial) layered shields.

**5. METHOD OF SOLUTION**

The three-dimensional point kernel volume integral for a cylindrical homogeneous source is calculated by Gauss integration. From the line-of-sight distance between point of integration and detector, mass attenuation and dose buildup are calculated, depending on the shielding material characteristics. For each shield layer, mass attenuation is determined from the actual elemental composition for the elements included in the built-in data library. Dose buildup factors are calculated recursively for subsequent layers according to Broder's formula. The coefficients for Broder's formula are interpolated in atomic number and energy for values not in the Goldstein data.

**6. RESTRICTIONS OR LIMITATIONS**

A maximum of 20 energies from 0.15 MeV to 10 MeV and 8 shield layers are allowed. Mass attenuation coefficients for the following 24 elements and 3 materials are included: H, Be, C, N, O, Na, Mg, Al, Si, P, S, A, K, Ca, Fe, Cu, Mo, Sn, I, W, Pt, Tl, Pb, U, air , water, concrete. A maximum of 5 compositions of up to 10 of these elements may be specified.

**7. TYPICAL RUNNING TIME**

The code is interactive. The sample input took only a about 1 minute on an IBM PC/XT (4.7 megahertz) running under DOS 3.3 with a math co-processor.

**8. COMPUTER HARDWARE REQUIREMENTS**

IBM PC and compatibles. A math coprocessor is not required. The code will also run on the VAX family of computers under the VMS operating system.

**9. COMPUTER SOFTWARE REQUIREMENTS**

The code was written in Fortran 77 and tested under PC-DOS (IBM PC). An executable file produced by the MICROSOFT Fortran Version 4.01 is included.

**
10. REFERENCE**

Geiser, H, Kuhl, H., Weyer, W. ``ZYLIND: An Interactive Point Kernel Program for Photon Dose Rate Prediction of Cylindrical Source/Shield Arrangement, User's Manual,'' Wissenschaftlich-Technische Ingenieurberatung GmbH, Germany, May 1989.

**11. CONTENTS OF CODE PACKAGE**

Included are the referenced document and a 5.25-in. DS/DD (360 K) diskette.

**12. DATE OF ABSTRACT**

October 1990.

**KEYWORDS: ** MICROCOMPUTER; INTERACTIVE; GAMMA-RAY;
CYLINDRICAL GEOMETRY; KERNEL