Flux measurement of the laser-Compton-backscattered photons with a Poisson fitting method

Abstract

Intensity of the laser-Compton-backscattered photons of Electrotechnical Laboratory has been measured using the Poisson fitting method. It was shown that pile-up events of the photons were simulated with the Poisson distribution quite well, and about 30 photons were generated per laser pulse.

Photoneutron cross sections for Ni isotopes: Toward understanding (n,γ) cross sections relevant to weak s -process nucleosynthesis

“…For the γ-ray flux determination, the pulsed LCS γray beam was measured with a large-volume (8" × 12") NaI(Tl) detector. The number of γ-rays, N γ , was determined from multi-photon spectra based on the Poissonfitting method [18,19] or the so-called pile-up method [20]. Recently, the accuracy of the experimental formula [20] used for the γ-flux determination was thoroughly investigated with the Poisson-fitting method, showing that the inherent uncertainty of the method is less than 0.1 % [21] provided that multi-photon spectra are free from quenching at the photomultiplier tube of the NaI(Tl) detector .…”

Photodisintegration cross section measurements onW186,Re187<

“…The pulse height of the spectrum is proportional to the number of LCS photons per beam pulse. The photon flux was determined with 3 % uncertainty based on a statistical analysis on the pile-up spectrum [24]. Os (0.97 %).…”

s-process branching atW185revised

“…Photons from a frequency- AIST and its application to photonuclear astrophysics can be found in [6,7,8,9].…”