Re: Be-window

["Evgeny Maev" <maev@pnpi.spb.ru>]

  Dear Peter,

  I prepare some comments about our study muon  stopping properties:

  1.We used SRIM code for calculation.
  2.The materials:
  mylar-0.075 mm , air-1.5 cm, Al-0.04 mm, scintillator(PilotB)-0.2 mm,
  air-1.0 cm, mylar-0.05 mm, PC1(Isobutane)-4cm, mylar-0.05 mm,air-1.5cm,
  Window- Be (0.8 mm ) or Havar (0.1mm ),
  Hydrogen- 30 cm at 10 bar pressure
  3.Muon beam-pencil beam without devergence .
  4.Scattering:
    We used for estimation the parameter-Lateral Projected Straggle (rms):
      Be(0.8mm)-25.1 mm . Beam Energy-5.6 MeV
      Havar(0.1 mm)-46.6 mm . Beam Energy-4.7 MeV
  5. Longitudinal Stragle (rms)-without beam momentum spread.
      Be(0.8 mm)-49.7 mm , Havar(0.1 mm)-40.2 mm
     With  3% FWHM  momentum spread the range straggling will be
     approcximately on 40% more.

    With best regards,
                       Evgeny


> Dear Evgeny,
>
> I will redo my old calculations as a check. A few questions:
>
> - Could you please send or fax (number below) me the PNPI technical
>   drawings of the windows! Is it 0.5 or 0.8 mm, you mention both
>   numbers below.
> - A can ask for a bit form a US companies, probably it is even more
>   expensive than your bid. But I would try.
> - Could you document your simulation a bit. I would then post it
>   on the webpage. In particular, what are the assumptions about the beam
> divergence?
>
> With best regards
>
> Peter