Recent content by XLAYZ

Sorry, I mean the radial distance from the axis of the beam with circular cross section.

Hello, I have an ordinary light (not laser) collimated to produce a parallel beam. After traveling a distance in air, the beam has diverged significantly. The intensity decreases as the radial distance increases. Now I need to estimate the intensity profile along all radial distances inside the...

Thank you for your hint, now I realized that I also need to take the wavelength into account. BTW, when a constant monochromatic light (λ≈420 nm) passes through a ø 2.5 mm and 15 mm collimator to produce parallel light beams, is this light unpolarized? Thanks.

Hello, I have a monochromatic light source (wavelength ~ 420 nm), which will be incident on the interface of two different media. Could someone please explain if the Fresnel equations applies with monochromatic light when estimating the reflectance and transmitance? Thank you in advance...

Yes, they were the Compton edges of gammas. Thanks.

Thanks, now I have figured it out. Those "peaks" were the Compton edges of the Pb-207 gammas.

I measured the decay spectrum of Bi-207 as a beta source with scintillation detector and now I am trying to interpret the information given by the spectrum. As far as I know, the Bi-207 nuclei decay to the excited states of Pb-207 primarily via EC and a small beta+ branch, emitting beta...