TNiel Class Reference

TNiel - the class providing values for NIEL factors. More...

#include <niel_fun.h>

Public Member Functions
	TNiel (const std::string &FileName)
	Constructor takes NIEL table for a particle as input.
double	getNielFactor (double EMeV)
	Get NIEL factor for a given particle energy.

Private Attributes
double	nielfactor [1710]
	factor values, enough to acommodate the longest file.
double	E_nielfactor [1710]
	particle energies at which the NIEL factor is tabulated.
int	niel_N
	number of rows in NIEL table

Detailed Description

TNiel - the class providing values for NIEL factors.

The class constructs a spline from a data table, and evaluates the spline at a desired point.

Definition at line 17 of file niel_fun.h.

Constructor & Destructor Documentation

TNiel()

TNiel ( const std::string &  FileName )

explicit

Constructor takes NIEL table for a particle as input.

Parameters

FileName

String containing the table filename.

Definition at line 44 of file niel_fun.cc.

{
  string fullName = FileSystem::findFile(FileName);
  if (fullName == "") {
    B2FATAL("TNIEL: Can't locate " << FileName);
    return;
  }
  ifstream inputfile;
  inputfile.open(fullName.c_str(), ifstream::in);
  if (!inputfile.good()) {
    B2FATAL("TNIEL: Error opening input file " << FileName);
    return;
  }
 
  B2INFO("Reading file " << FileName);
 
  int i = 0;
  string line;
  while (getline(inputfile, line)) {
    istringstream iss(line);
    if (!(iss >> E_nielfactor[i] >> nielfactor[i])) {
      B2FATAL("Error reading NIEL correction data from " << fullName.c_str());
      break;
    }
    i++;
  }
  inputfile.close();
  niel_N = i;
  B2INFO("INITIALIZED TNIEL FROM " << fullName.c_str());
  for (int j = 0; j < niel_N; j++)
    B2DEBUG(100, "E: " << E_nielfactor[j] << " N: " << nielfactor[j]);
}

Member Function Documentation

getNielFactor()

double getNielFactor

(

double

EMeV

)

Get NIEL factor for a given particle energy.

Parameters

EMeV	particle kinetic energy in MeV.

Returns

NIEL factor for a particle with a given energy.

Definition at line 77 of file niel_fun.cc.

{
  // input energy in MeV
  int j = niel_N;
  for (int i = 0; i < niel_N; i++) {
    if (EMeV < E_nielfactor[i]) {
      j = i;
      break;
    }
  }
  double value;
  if (j > 0 && j < niel_N)
    value = nielfactor[j - 1]
            + (nielfactor[j] - nielfactor[j - 1])
            / (E_nielfactor[j] - E_nielfactor[j - 1])
            * (EMeV - E_nielfactor[j - 1]);
  else if (j == 0)
    value = nielfactor[0];
  else
    value = nielfactor[niel_N - 1];
  return value;
}

Member Data Documentation

E_nielfactor

double E_nielfactor[1710]

private

particle energies at which the NIEL factor is tabulated.

Definition at line 22 of file niel_fun.h.

niel_N

int niel_N

private

number of rows in NIEL table

Definition at line 23 of file niel_fun.h.

nielfactor

double nielfactor[1710]

private

factor values, enough to acommodate the longest file.

Definition at line 21 of file niel_fun.h.

---

The documentation for this class was generated from the following files:

• vxd/background/include/niel_fun.h
• vxd/background/src/niel_fun.cc