pseudoscalar_stoch_conn_s.cc

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#include "chromabase.h"
#include "pseudoscalar_stoch_conn_s.h"
#include "util/gauge/stag_phases_s.h"
#include "meas/smear/fuzz_smear.h"
 
namespace Chroma {
 
// Standard Time Slicery
class TimeSliceFunc : public SetFunc
{
public:
  TimeSliceFunc(int dir): dir_decay(dir) {}
 
  int operator() (const multi1d<int>& coordinate) const {return coordinate[dir_decay];}
  int numSubsets() const {return Layout::lattSize()[dir_decay];}
 
  int dir_decay;
 
private:
  TimeSliceFunc() {}  // hide default constructor
};
 
 
  /* README:
   * this code hopefully does the measurements necessary to compute 
   * connected correlators (for 4-link taste singlet pseudoscalar mesons.
   * it does not  compute the correlator itself. Two quantities are 
   * written out for each pair of noise source vectors; call them C1 and C2.
   * the connected correlator should be <<C1(x)*C2(y)>>, where <<>> is an 
   * average over noise sources, This is in contrast to the disconnected
   * correlator, which should be assembled as <<D1(x)*>><<D1(y)>>. Of course
   * and average over configurations is assumed.
   */
 
 
 
void fourlink_pseudoscalar_stoch_conn::compute(
                                    LatticeStaggeredFermion & q_source1,
                                    LatticeStaggeredFermion & q_source2,
                                    LatticeStaggeredFermion & psi1, 
                                    LatticeStaggeredFermion & psi2,
                                    int isample){
  // Array to describe shifts in cube
  multi1d<int> delta(Nd);
 
  Set timeslice;
  timeslice.make(TimeSliceFunc(Nd-1));
 
  LatticeStaggeredFermion psi_eta4_1 ;
  LatticeStaggeredFermion psi_eta4_2 ;
 
  delta = 0;
  delta[0] = delta[1] = delta[2] = delta[3] = 1;
 
  psi_eta4_1 = shift_deltaProp(delta, psi1);
  psi_eta4_2 = shift_deltaProp(delta, psi2);
 
  LatticeComplex TrG_eta4 ; 
 
  using namespace StagPhases;
 
  TrG_eta4 = 
    -alpha(0)*alpha(1)*alpha(2)*alpha(3)*localInnerProduct(q_source1, 
                                                           psi_eta4_2);
 
  corr_fn1[isample] = sumMulti(TrG_eta4, timeslice);
  corr1 += corr_fn1[isample] ;
 
  TrG_eta4 = 
    -alpha(0)*alpha(1)*alpha(2)*alpha(3)*localInnerProduct(q_source2, 
                                                           psi_eta4_1);
  corr_fn2[isample] = sumMulti(TrG_eta4, timeslice);
  corr2 += corr_fn2[isample] ;
}
 
void fourlink_pseudoscalar_stoch_conn::compute(
                                    LatticeStaggeredFermion & q_source1,
                                    LatticeStaggeredFermion & q_source2,
                                    LatticeStaggeredFermion & psi1, 
                                    LatticeStaggeredFermion & psi2,
                                    //              bool fuzz_src, bool fuzz_sink,
                                    const multi1d<LatticeColorMatrix> & u_smr,
                                    int fuzz_width,
                                    int j_decay,        
                                    int isample){
 
  // Array to describe shifts in cube
  multi1d<int> delta(Nd);
 
 
  Set timeslice;
  timeslice.make(TimeSliceFunc(Nd-1));
 
  LatticeStaggeredFermion psi_eta4_1 ;
  LatticeStaggeredFermion psi_eta4_2 ;
 
  LatticeStaggeredFermion  fuzz_q_source1;
  LatticeStaggeredFermion  fuzz_q_source2;
  LatticeStaggeredFermion  fuzz_psi_1;
 
  delta = 0;
  delta[0] = delta[1] = delta[2] = delta[3] = 1;
 
 
  if(Fsink){
        fuzz_smear(u_smr, psi1, fuzz_psi_1, fuzz_width, j_decay) ;
        psi_eta4_1 = shift_deltaProp(delta, fuzz_psi_1);
 
  }else{
    psi_eta4_1 = shift_deltaProp(delta, psi1);
  }
 
 
  psi_eta4_2 = shift_deltaProp(delta, psi2);
 
  LatticeComplex TrG_eta4 ; 
 
  using namespace StagPhases;
 
  if(Fsrc){
    fuzz_smear(u_smr, q_source1, fuzz_q_source1, fuzz_width, j_decay) ;
 
    TrG_eta4 = 
      -alpha(0)*alpha(1)*alpha(2)*alpha(3)*localInnerProduct(fuzz_q_source1,
                                                             psi_eta4_2);
  }else{
    TrG_eta4 = 
      -alpha(0)*alpha(1)*alpha(2)*alpha(3)*localInnerProduct(q_source1, 
                                                             psi_eta4_2);
  }
 
 
 
  corr_fn1[isample] = sumMulti(TrG_eta4, timeslice);
  corr1 += corr_fn1[isample] ;
 
 
  TrG_eta4 = 
    -alpha(0)*alpha(1)*alpha(2)*alpha(3)*localInnerProduct(q_source2, 
                                                           psi_eta4_1);
  corr_fn2[isample] = sumMulti(TrG_eta4, timeslice);
  corr2 += corr_fn2[isample] ;
}
 
 
}  // end namespace Chroma