ReactorConstants.hh Source File

00001 
00006 #ifndef REACTORCONSTANTS_HH
00007 #define REACTORCONSTANTS_HH
00008 
00013 class ReactorConstants{
00014   //
00015   // Common set of constants for simulation.
00016   //
00017 public:  
00018   //  
00019   // For neutrino event generation
00020   // XCorder can be changed to 0 to use neglect 1/M effects in the nubar 
00021   // cross section.
00022   // Emin,Emax set the range of thrown energy.
00023   // Rmaxgen sets the largest production radius
00024   //
00025   static const int XCorder = 1;  
00026   static const double Emin=1.85;
00027   static const double Emax=8.15;
00028   static const double Rmaxgen = 265;
00029   //
00030   // Cf source isotope
00031   //
00032   static const int Isotope = 252;
00033   //
00034   // Number of all particles we can handle
00035   //
00036   static const int Ndim = 200;
00037   //
00038   // R0 = Gd loaded radius
00039   // R1 = unloaded scintillator radius
00040   // R2 = inactive mineral oil radius
00041   //
00042   static const double R0 = 175;
00043   static const double R1 = 200;
00044   static const double R2 = 275;
00045   //
00046   // throw neutron via Gaussian or track
00047   //
00048   static const bool FastNeutronOption=0;
00049   static const double SlowNeutronStep=0.1;
00050   //
00051   // units=Kelvin
00052   //
00053   static const double Temperature=300;
00054   //
00055   // units = MeV/Kelvin
00056   //
00057   static const double Kboltzman = 8.617342e-11;
00058   //
00059   // basics
00060   //
00061   static const double pi = 3.1415928;
00062   static const double Mproton = 938.27200;
00063   //
00064   // Mneutron-Mproton
00065   //
00066   static const double Delta = 1.2933318;
00067   static const double Melectron = 0.510998902;
00068   static const double Mmuon = 105.6583692;
00069   //
00070   // 1/alpha
00071   //
00072   static const double alphainv = 137.03599976;
00073   //
00074   // Gfermi in MeV**(-2)
00075   // 
00076   static const double Gfermi = 1.16639e-11;
00077   static const double Navogadro = 6.02214199e23;
00078   //
00079   //classical electron radius
00080   //
00081   static const double Relectron = 2.817940285e-13;  
00082   //
00083   // conversion for cross sections from (Mev)**-2 to cm**2.
00084   //
00085   static const double XcMeVtoCmsqrd = 0.389379292e-21;
00086   //
00087   //  c in cm/ns
00088   //
00089   static const double c = 29.9792458;
00090   //
00091   // Scintillator and mineral oil constants taken from Chooz.
00092   // Only H are C are taken into account.
00093   //
00094   static const double density = 0.85;
00095   static const double A0=1;
00096   static const double A1=12;
00097   static const double A2=155;
00098   static const double A3=157;
00099   static const double Z0=1;
00100   static const double Z1=6;
00101   static const double Z2=64;
00102   static const double Z3=64;
00103   //
00104   // H and C mass fractions for scintillator
00105   //
00106   static const double f0=0.122;
00107   static const double f1=0.844;
00108   //
00109   // note these are the abundances of Gd155,Gd157
00110   //
00111   static const double f2=0.148;
00112   static const double f3=0.156;
00113   //
00114   // H and C mass fractions for mineral oil
00115   //
00116   static const double f4=0.133;
00117   static const double f5=0.855;
00118   //
00119   // Ionization potentials for dE/dx
00120   //
00121   static const double I0=19.2e-6;
00122   static const double I1=78.0e-6;  
00123   //
00124   // from the Chooz EPJC article
00125   // index of refraction
00126   //
00127   static const double refracGd = 1.472;
00128   static const double refracSc = 1.476;
00129   //
00130   // Gd fraction(%)
00131   //
00132   // NOTE: GdConcentration should not be blindly changed because the
00133   // values for mfpGd, tGd, GdCaptureFraction below are based on a 
00134   // GdConcentration of 0.1
00135   // Instead use ReactorDetector::SetParam_GdConcentration which 
00136   // handles resetting all these values.
00137   //
00138   static const double GdConcentration = 0.1;
00139   static const double GdConcentrationRef = 0.1;
00140   //
00141   // neutron mean free path in Gd- or un-loaded
00142   //
00143   static const double mfpGd =  6;
00144   static const double mfpSc = 40;
00145   //
00146   // mean forward displacement of neutrons (from Chooz)
00147   //
00148   static const double MeanNeuDispl = 1.7;
00149   //  capture times in ns for neutrons
00150   //  These have been adjusted to give mean capture times of 30.5 us and
00151   //  180 us in Gd and unloaded Sc, respectively 
00152   //
00153   //
00154   static const double tGd = 24.7e3;
00155   static const double tSc = 145.8e3;
00156   //
00157   // properties of capture in Gd region
00158   // GdCaptureFraction is the fraction of neutrons captured on Gd
00159   // The program assumes capture on Gd155 or 157.  Gd155frac is the
00160   // fraction pf Gd155 capture, etc.
00161   // Gd155peak is the total energy release from Gd155 capture.
00162   //
00163   static const double GdCaptureFraction = 0.841;
00164   static const double Gd155frac = 0.1848;
00165   static const double Gd155peak = 8.536;
00166   static const double Gd157frac = 0.8152;
00167   static const double Gd157peak = 7.937;
00168   //
00169   // This is an ad-hoc guess for the average number of gammas/per Gd.
00170   // The program in practice generates at least two gammas per capture
00171   // and an additional Poisson fluctuated GammasPerGd-2.
00172   //
00173   static const double GammasPerGd = 3;
00174   //
00175   // From capture on H
00176   // This is the gamma energy from np->D gamma.
00177   //
00178   static const double Hpeak = 2.2246;
00179   //
00180   // For capture on C12
00181   //
00182   static const double Cpeak = 4.9461;
00183   //
00184   // Attenuation lengths in Gd- or un-loaded
00185   // These are taken from Chooz.
00186   //
00187   static const double attenlGd =  400;
00188   static const double attenlSc = 1000;
00189   //
00190   // From Chooz-1 scintillator
00191   //  
00192   static const double PhotonsPerMeV = 5300;
00193   //
00194   // Scintillator decay time (ns)
00195   //
00196   static const double ScintDecayTime = 7;
00197   //
00198   // Positron annihilation times from KAMLAND 
00199   //    Y. Kino et al.
00200   //    J. Nucl. Radiochem. Science 1, 63, 200
00201   // Not yet used.
00202   //
00203   static const double ShortPosFrac0 = 0.30;
00204   static const double ShortPosFrac1 = 0.21;
00205   static const double LongPosFrac = 0.49;
00206   static const double ShortPosTime0 = 0.19;
00207   static const double ShortPosTime1 = 0.48;
00208   static const double LongPosTime = 3.41;
00209   //
00210   // Some PMT properties.
00211   // 8 inch diameter PMT
00212   //
00213   static const double PMTcoverage = 0.2;
00214   static const double PMTdiameter = 20.16;
00215   //
00216   // Quantum efficiency for photostatistics. 
00217   //
00218   static const double PMTqe = 0.2;
00219 };
00220 #endif