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 = 200;
00029   //
00030   // Cf source isotope
00031   //
00032   static const int Isotope = 252;
00033   //
00034   // Number of each type of particle we can handle
00035   //
00036   static const int Ndim = 100;
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   //
00069   // 1/alpha
00070   //
00071   static const double alphainv = 137.03599976;
00072   //
00073   // Gfermi in MeV**(-2)
00074   // 
00075   static const double Gfermi = 1.16639e-11;
00076   static const double Navogadro = 6.02214199e23;
00077   //
00078   //classical electron radius
00079   //
00080   static const double Relectron = 2.817940285e-13;  
00081   //
00082   // conversion for cross sections from (Mev)**-2 to cm**2.
00083   //
00084   static const double XcMeVtoCmsqrd = 0.389379292e-21;
00085   //
00086   //  c in cm/ns
00087   //
00088   static const double c = 29.9792458;
00089   //
00090   // Scintillator and mineral oil constants taken from Chooz.
00091   // Only H are C are taken into account.
00092   //
00093   static const double density = 0.85;
00094   static const double A0=1;
00095   static const double A1=12;
00096   static const double A2=155;
00097   static const double A3=157;
00098   static const double Z0=1;
00099   static const double Z1=6;
00100   static const double Z2=64;
00101   static const double Z3=64;
00102   //
00103   // Mass fractions
00104   //
00105   static const double f0=0.122;
00106   static const double f1=0.844;
00107   //
00108   // note these are the abundances of Gd155,Gd157
00109   //
00110   static const double f2=0.148;
00111   static const double f3=0.156;
00112   //
00113   // and these are for mineral oil
00114   //
00115   static const double f4=0.133;
00116   static const double f5=0.855;
00117   //
00118   // Ionization potentials for dE/dx
00119   //
00120   static const double I0=19.2e-6;
00121   static const double I1=78.0e-6;  
00122   //
00123   // from the Chooz EPJC article
00124   // index of refraction
00125   //
00126   static const double refracGd = 1.472;
00127   static const double refracSc = 1.476;
00128   //
00129   // Gd fraction(%)
00130   //
00131   static const double GdConcentration = 0.1;
00132   static const double GdConcentrationRef = 0.1;
00133   //
00134   // neutron mean free path in Gd- or un-loaded
00135   //
00136   static const double mfpGd =  6;
00137   static const double mfpSc = 40;
00138   //
00139   // mean forward displacement of neutrons (from Chooz)
00140   //
00141   static const double MeanNeuDispl = 1.7;
00142   //  capture times in ns for neutrons
00143   //  These have been adjusted to give mean captur times of 30.5 us and
00144   //  180 us in Gd and unloaded Sc, respectively 
00145   //
00146   //
00147   static const double tGd = 24.7e3;
00148   static const double tSc = 145.8e3;
00149   //
00150   // properties of capture in Gd region
00151   // GdCaptureFraction is the fraction of neutrons captured on Gd
00152   // The program assumes capture on Gd155 or 157.  Gd155frac is the
00153   // fraction pf Gd155 capture, etc.
00154   // Gd155peak is the total energy release from Gd155 capture.
00155   //
00156   static const double GdCaptureFraction = 0.841;
00157   static const double Gd155frac = 0.1848;
00158   static const double Gd155peak = 8.536;
00159   static const double Gd157frac = 0.8152;
00160   static const double Gd157peak = 7.937;
00161   //
00162   // This is an ad-hoc guess for the average number of gammas/per Gd.
00163   // The program in practice generates at least two gammas per capture
00164   // and an additional Poisson fluctuated GammasPerGd-2.
00165   //
00166   static const double GammasPerGd = 3;
00167   //
00168   // From capture on H
00169   // This is the gamma energy from np->D gamma.
00170   //
00171   static const double Hpeak = 2.2246;
00172   //
00173   // For capture on C12
00174   //
00175   static const double Cpeak = 4.9461;
00176   //
00177   // Attenuation lengths in Gd- or un-loaded
00178   // These are taken from Chooz.
00179   //
00180   static const double attenlGd =  400;
00181   static const double attenlSc = 1000;
00182   //
00183   // From Chooz-1 scintillator
00184   //  
00185   static const double PhotonsPerMeV = 5300;
00186   //
00187   // Scintillator decay time (ns)
00188   //
00189   static const double ScintDecayTime = 7;
00190   //
00191   // Positron annihilation times from KAMLAND 
00192   //    Y. Kino et al.
00193   //    J. Nucl. Radiochem. Science 1, 63, 200
00194   // Not yet used.
00195   //
00196   static const double ShortPosFrac0 = 0.30;
00197   static const double ShortPosFrac1 = 0.21;
00198   static const double LongPosFrac = 0.49;
00199   static const double ShortPosTime0 = 0.19;
00200   static const double ShortPosTime1 = 0.48;
00201   static const double LongPosTime = 3.41;
00202   //
00203   // Some PMT properties.
00204   // 8 inch diameter PMT
00205   //
00206   static const double PMTcoverage = 0.2;
00207   static const double PMTdiameter = 20.16;
00208   //
00209   // Quantum efficiency for photostatistics. 
00210   //
00211   static const double PMTqe = 0.2;
00212 };
00213 #endif