ReactorConstants.hh Source File

00001 #ifndef REACTORCONSTANTS_HH
00002 #define REACTORCONSTANTS_HH
00003 
00004 class ReactorConstants{
00005   //
00006   // Common set of constants for simulation.
00007   //
00008 public:  
00009   //  
00010   // For neutrino event generation
00011   // XCorder can be changed to 0 to use neglect 1/M effects in the nubar 
00012   // cross section.
00013   // Emin,Emax set the range of thrown energy.
00014   // Rmaxgen is the 
00015   //
00016   static const int XCorder = 1;  
00017   static const double Emin=1.85;
00018   static const double Emax=8.15;
00019   static const double Rmaxgen = 200;
00020   //
00021   // R0 = Gd loaded radius
00022   // R1 = unloaded scintillator radius
00023   // R2 = inactive mineral oil radius
00024   //
00025   static const double R0 = 175;
00026   static const double R1 = 200;
00027   static const double R2 = 275;
00028   //
00029   // throw neutron via Gaussian or track
00030   //
00031   static const bool FastNeutronOption=0;
00032   static const double SlowNeutronStep=0.1;
00033   //
00034   // units=Kelvin
00035   //
00036   static const double Temperature=300;
00037   //
00038   // units = MeV/Kelvin
00039   //
00040   static const double Kboltzman = 8.617342e-11;
00041   //
00042   // basics
00043   //
00044   static const double pi = 3.1415928;
00045   static const double Mproton = 938.27200;
00046   //
00047   // Mneutron-Mproton
00048   //
00049   static const double Delta = 1.2933318;
00050   static const double Melectron = 0.510998902;
00051   //
00052   // 1/alpha
00053   //
00054   static const double alphainv = 137.03599976;
00055   //
00056   // Gfermi in MeV**(-2)
00057   // 
00058   static const double Gfermi = 1.16639e-11;
00059   static const double Navogadro = 6.02214199e23;
00060   //
00061   //classical electron radius
00062   //
00063   static const double Relectron = 2.817940285e-13;  
00064   //
00065   // conversion for cross sections from (Mev)**-2 to cm**2.
00066   //
00067   static const double XcMeVtoCmsqrd = 0.389379292e-21;
00068   //
00069   //  c in cm/ns
00070   //
00071   static const double c = 29.9792458;
00072   //
00073   // Scintillator constants taken from Chooz.
00074   // Only H are C are taken into account.
00075   //
00076   static const double density = 0.85;
00077   static const double A0=1;
00078   static const double A1=12;
00079   static const double A2=155;
00080   static const double A3=157;
00081   static const double Z0=1;
00082   static const double Z1=6;
00083   static const double Z2=64;
00084   static const double Z3=64;
00085   //
00086   // Mass fractions
00087   //
00088   static const double f0=0.122;
00089   static const double f1=0.844;
00090   //
00091   // note these are the abundances of Gd155,Gd157
00092   //
00093   static const double f2=0.148;
00094   static const double f3=0.156;
00095   //
00096   // Ionization potentials for dE/dx
00097   //
00098   static const double I0=19.2e-6;
00099   static const double I1=78.0e-6;  
00100   //
00101   // from the Chooz EPJC article
00102   // index of refraction
00103   //
00104   static const double refracGd = 1.472;
00105   static const double refracSc = 1.476;
00106   //
00107   // Gd fraction(%)
00108   //
00109   static const double GdConcentration = 0.1;
00110   static const double GdConcentrationRef = 0.1;
00111   //
00112   // neutron mean free path in Gd- or un-loaded
00113   //
00114   static const double mfpGd =  6;
00115   static const double mfpSc = 40;
00116   //
00117   // mean forward displacement of neutrons (from Chooz)
00118   //
00119   static const double MeanNeuDispl = 1.7;
00120   //  capture times in ns for neutrons
00121   //  These have been adjusted to give mean captur times of 30.5 us and
00122   //  180 us in Gd and unloaded Sc, respectively 
00123   //
00124   //
00125   static const double tGd = 24.7e3;
00126   static const double tSc = 145.8e3;
00127   //
00128   // properties of capture in Gd region
00129   // GdCaptureFraction is the fraction of neutrons captured on Gd
00130   // The program assumes capture on Gd155 or 157.  Gd155frac is the
00131   // fraction pf Gd155 capture, etc.
00132   // Gd155peak is the total energy release from Gd155 capture.
00133   //
00134   static const double GdCaptureFraction = 0.841;
00135   static const double Gd155frac = 0.1848;
00136   static const double Gd155peak = 8.536;
00137   static const double Gd157frac = 0.8152;
00138   static const double Gd157peak = 7.937;
00139   //
00140   // This is an ad-hoc guess for the average number of gammas/per Gd.
00141   // The program in practice generates at least two gammas per capture
00142   // and an additional Poisson fluctuated GammasPerGd-2.
00143   //
00144   static const double GammasPerGd = 3;
00145   //
00146   // From capture on H
00147   // This is the gamma energy from np->D gamma.
00148   //
00149   static const double Hpeak = 2.2246;
00150   //
00151   // For capture on C12
00152   //
00153   static const double Cpeak = 4.9461;
00154   //
00155   // Attenuation lengths in Gd- or un-loaded
00156   // These are taken from Chooz.
00157   //
00158   static const double attenlGd =  400;
00159   static const double attenlSc = 1000;
00160   //
00161   // From Chooz-1 scintillator
00162   //  
00163   static const double PhotonsPerMeV = 5300;
00164   //
00165   // Scintillator decay time (ns)
00166   //
00167   static const double ScintDecayTime = 7;
00168   //
00169   // Positron annihilation times from KAMLAND 
00170   //    Y. Kino et al.
00171   //    J. Nucl. Radiochem. Science 1, 63, 200
00172   // Not yet used.
00173   //
00174   static const double ShortPosFrac0 = 0.30;
00175   static const double ShortPosFrac1 = 0.21;
00176   static const double LongPosFrac = 0.49;
00177   static const double ShortPosTime0 = 0.19;
00178   static const double ShortPosTime1 = 0.48;
00179   static const double LongPosTime = 3.41;
00180   //
00181   // Some PMT properties.
00182   // 8 inch diameter PMT
00183   //
00184   static const double PMTcoverage = 0.2;
00185   static const double PMTdiameter = 20.16;
00186   //
00187   // Quantum efficiency for photostatistics. 
00188   //
00189   static const double PMTqe = 0.2;
00190 };
00191 #endif