IAEA1269 DIFBAS.

1. NAME OR DESIGNATION OF PROGRAM:  DIFBAS

3. DESCRIPTION OF PROGRAM OR FUNCTION

The main purpose of the DIFBAS  code is to unfold pulse height spectra measured by a proton recoil detector (e.g. H filled proportional counters or organic scintillators) to obtain neutron spectra. It can be used generally for the unfolding of arbitrary many channel spectra containing original particle spectra folded by a detector response (e.g. spectra of photon detectors).

4. METHOD OF SOLUTION

The algorithm is based on the Bayesian conditional probability assuming normal distributions of both the pulse height and the a priori spectra. The covariance filter method, which avoids any matrix inversion, is employed to calculate the a-posteriori spectrum and covariance matrix of the neutron spectrum.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM:

6. TYPICAL RUNNING TIME

Strongly depends on dimensions of the response matrix. The sample case (138*136 bins) takes about 7 min on 33 MHz PC (386).

7. UNUSUAL FEATURES OF THE PROGRAM:

8. RELATED AND AUXILIARY PROGRAMS

The following codes are added to the package:
- RMC, MB as interface to the code NRESP7 for the calculation of the   NE213 response matrix;
- SPHC for PH spectrum rebinning and the corresponding covariance   matrix calculation;
- FOC, CUPR for use of unformatted output fluence and covariance   files.

10. REFERENCES:

- Milos Tichy:
  The DIFBAS Program - Description and User's Guide
  PTB-7.2-93-1 (April 1993) + Errata
- Milos Tichy:
  Letter to M. Loechte dated 17 March 1994 concerning DIFBAS Code.

11. MACHINE REQUIREMENTS

IBM-PC with at least 600kB user usable memory. The requirements sharply depend on the response matrix dimensions.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED: , MS-DOS (PC), VMS (VAX).

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

The program can be used with minor changes on any computer with a Fortran 77 compiler and a sufficient amount memory.

15. NAME AND ESTABLISHMENT OF AUTHORS

Milos Tichy
Institute of Radiation Dosimetry
Czechoslovak Academy of Science
Na Truhlarce 39
18086 Prague 8, Czeck Republic

File name	File description	Records
IAEA1269_01.001	Information file	235
IAEA1269_01.002	Abstract list	80
IAEA1269_01.003	Installation description	138
IAEA1269_01.004	file description for supporting codes	20
IAEA1269_01.005	file description for supporting codes	20
IAEA1269_01.006	Additional information for PHT14.DER	8
IAEA1269_01.007	PC-version of DIFBAS	1579
IAEA1269_01.008	VAX-version of DIFBAS	1577
IAEA1269_01.009	PC-VAX differences	254
IAEA1269_01.010	Sample case 1	24
IAEA1269_01.011	Sample case 2	24
IAEA1269_01.012	Data file for test case 1	189
IAEA1269_01.013	Spectrum file	179
IAEA1269_01.014	output test case 1 & 2 (PC)	365
IAEA1269_01.015	Results of test case 1 & 2 (VAX)	362
IAEA1269_01.016	Response matrix conversion code	92
IAEA1269_01.017	PH spectrum conversion code	64
IAEA1269_01.018	Input file for TRANSMAT	9900
IAEA1269_01.019	Input file for TRANSPHS	3270
IAEA1269_01.020	Format conversion code for PC	414
IAEA1269_01.021	Format conversion code for VAX	414
IAEA1269_01.022	PH spectrum conversion code	348
IAEA1269_01.023	PH spectrum conversion code (VAX)	379
IAEA1269_01.024	PH conversion code (ASCII)	378
IAEA1269_01.025	Input file for SPHC	412
IAEA1269_01.026	Interface code (NRESP7/MB) for PC	109
IAEA1269_01.027	Interface code (NRESP7/MB) for VAX	109
IAEA1269_01.028	Input file for RMC	5
IAEA1269_01.029	Protocol file of RMC	188
IAEA1269_01.030	Response matrix generation code (PC)	345
IAEA1269_01.031	Response matrix generation code (VAX)	345
IAEA1269_01.032	Input file for MB	6
IAEA1269_01.033	Protocol file of MB	209
IAEA1269_01.034	Supporting code for MB	88
IAEA1269_01.035	Covariance utility code	461
IAEA1269_01.036	Supporting code for DIFBAS (PC)	460
IAEA1269_01.037	supporting code for DIFBAS (VAX)	460
IAEA1269_01.038	Input file for GOALRE	7
IAEA1269_01.039	Input data file for GOALRE	9
IAEA1269_01.040	Input file for NRESP7	1418