Constructing a gas material with temp/press in a pure VGM construction.

From: Brett Viren <bv_at_bnl.gov>
Date: Mon, 30 Oct 2006 19:46:47 -0500

Hi,

Is it possible in a pure VGM construction to define a gas material with a temperature and pressure? For example, I have the following Geant4 "Vacuum" material that I want to construct given a VGM::IMaterialFactory:

// Air

  density = 1.205e-3*g/cm3;
  Air = new G4Material(name="Air", density, nel=4);

  Air->AddElement(elN, 0.7550);
  Air->AddElement(elO, 0.2321);
  Air->AddElement(elAr, 0.0128);
  Air->AddElement(elC, 0.0001);

// Vacuum
// --- PMT vacuum is very dilute air -------

  density     =  1e-3 * kGasThreshold;         //from PhysicalConstants.h
  G4double temperature = STP_Temperature;         //from PhysicalConstants.h

  G4double pressure = STP_Pressure * density / (1.29e-3*g/cm3);   Vacuum = new G4Material(name="Vacuum", density, 1, kStateGas,temperature,pressure);   Vacuum->AddMaterial(Air, 1.);

I know how to convert "Air", but not "Vacuum".

Thanks for any help,
-Brett. Received on Tue Oct 31 2006 - 01:46:59 MET