K3.1 - Station for studies of photonuclear reactions "GAMMA"

The station is dedicated for the research of photonuclear reactions in wide energy range from threshold to 2.5 GeV, as well as for various applied tasks, including the calibration of nuclear detectors, radiation materials science, measurement and optimization of beam parameters.

Methods:

• Bremsstrahlung deceleration radiation with the maximum spectral range from 0,4 up to 1,0 GeV on the residual gas of storage with the use of the labeling system for monochromatization of energy with the resolution about 10 MeV and full intensity up to 10⁶ s^-1;
• the reverse Compton radiation with the energy from 100 MeV up to 400 MeV on the basis of argon laser; full intensity of the beam up to 10⁷ s^-1 with the energy resolution about 10 MeV with the use of labeling system;
• the reverse Compton radiation with the energy from 20 MeV on the basis of ян₂ laser; full intensity of the beam up to 10⁹ s^-1 with the energy resolution about 0,1 MeV with the use of collimation for monochromatization of the beam.

X-ray optical scheme:

The station equipped with:

• CO₂ laser, single-mode, power up to 1 kW;
• Gamma spectrometer with resolution 5%;
• Gamma beam monitor with resolution 0.1 mm.

Parameters:

• deceleration radiation energy up to 2.5 GeV, intensity up to 10⁷ s^-1, DE/E = 1% using labeling system;
• Compton radiation energy up to 20 MeV, intensity up to 10⁹ s^-1, DE/E = 5% using collimation;
• scattering angles range: 0-10 mrad;
• precision of laser beam positioning ~ 0.1 seconds of arc.

Results:

Experiments on photofission of 238U nuclei using tracking detectors where carried out at the front end of GAMMA beamline [2]. The results are basically methodical. Images of tracking detectors (polycarbone films), taken using electric-spark disruption method with exposure 135 mA/h (upper picture) and 54mA/h (lower picture) are shown in the figures below. The corresponding profiles of the deceleration gamma beam at a distance of 6 m from the linear section of the storage ring are shown on the right.

References

Address: 1 Academic Kurchatov sq.,
Moscow, 123182, Russian Federation
RRC "Kurchatov Institute", KCSRNT
Phone: +7 (499) 196-75-38, 196-71-10
Fax: +7 (499) 196-77-23
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