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Manuscript Title: A computer program for nuclear lifetimes measurements by DSAM using a self supporting target.
Authors: C. Morand, T.-U. Chan
Program title: DSAMER
Catalogue identifier: ABQM_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 23(1981)393
Programming language: Fortran.
Computer: CDC 6600.
Operating system: NOS/BE 1.
RAM: 4K words
Word size: 60
Peripherals: disc.
Keywords: Nuclear physics, Gamma spectroscopy, Apparatus design, Nuclear physics, Gamma spectroscopy, Apparatus design, Nuclear level lifetimes, Doupler shift Attenuation method, Line shape fit, Nuclear stopping powers, Recoiling nuclei Velocity: Beta=one per cent.
Classification: 17.1, 17.4.

Nature of problem:
DSAM for nuclear lifetime measurements needs accurate nuclear stopping powers. Using self supporting targets and known long-lived levels, DSAM satisfies that condition and thus provides rather good lifetime measurements.

Solution method:
For given lifetime and stopping powers, the line shape of the Doppler Doppler distorted gamma-ray is built up by taking into account successively the
- particle evaporation (n,p,alpha)
- slowing-down of the recoiling nuclei in the target,
- different feeding laws of the studied levels,
- energy response of the GeLi detector used (including solid angle correction).
The best fit of the experimental line is chosen by the chi-square criterion.

Restrictions:
- Number of evaporated particles must be <=3, (2 alpha maximum), - range of lifetime measurements: 0.02 ps< tau < 5ps, - typical recoiling ions initial velocity : Beta =1%, typical nuclei mass and target: 50 < A < 80, typical target thickness: 1 mg/cmsq, - number of mixed gamma rays to be analyzed must be <=2.

Running time:
About 1/2 s for one line-shape fit.