float n3HeSim(int nev_=0, float rfsf_phi_=300, int sev=0)
{
// commandline option '-var=val' to change any global
for (int i=1; i<gApplication->Argc(); ++i)
{
TString opt(gApplication->Argv(i));
if ((opt[0]=='-' || opt[0]=='+') && opt.Contains("="))
gROOT->ProcessLine(opt=opt.Append(";").Strip(TString::kLeading,'-'));
}
if (nev_)
nev = nev_;
if (rfsf_phi_!=0)
rfsf_phi=rfsf_phi_/360.;
TFile* f = new TFile("/home/siplu/GIT/n3He_Soft/Github/Simulation/data/mcstas.root");
TNtuple* ntp = (TNtuple*)f->Get("mcstas");
// set up ntuple
BRANCH(l);
BRANCH(pol);
BRANCH(p5);
BRANCH(p6);
BRANCH(t6);
BRANCH(x6);
BRANCH(y6);
BRANCH(vx6);
BRANCH(vy6);
BRANCH(vz6);
float chop[4];
TBranch* b_chop[4];
for (int j=0;j<nch;++j)
{
b_chop[j]=ntp->GetBranch(vch[j]);
ntp->SetBranchAddress(vch[j],&chop[j]);
}
// precalculate track projections
float dwc = lwc/nz; // WC parameters
float da = 2./na, a0=-1+da/2; // polar [cos(theta)] integration
float db = 2*PI/nb, b0=-PI+db/2; // azimuthal [phi] integration
float cxyz[3], &cx=cxyz[0],&cy=cxyz[1],&cz=cxyz[2]; // projection cosines
float ccz[NDIV], ccx[NDIV][NDIV], ccy[NDIV][NDIV], as; // cached values
float aa=a0;
for (int ia=0; ia<na; ++ia, aa+=da)
{
ccz[ia]=aa;
if (ccz[ia]==0)
ccz[ia]=1e-11;
as=sqrt(1-aa*aa);
float bb=b0;
for (int ib=0; ib<nb; ++ib, bb+=db)
{
ccx[ia][ib]=as*cos(bb);
if (ccx[ia][ib]==0)
ccx[ia][ib]=1e-11;
ccy[ia][ib]=as*sin(bb);
if (ccy[ia][ib]==0)
ccy[ia][ib]=1e-11;
}
}
// cumulative beta distribution
for (int i=0;i<nbet;++i)
beta_int[i+1]=beta_int[i]+beta_pt[i];
// initialize WC response matrices
double n5 = 0; // pre-polarizer neutrons
double N[NTOF]={0}; // chopped neutrons at end of SMpol
double P2N[NTOF]={0}; // " * P^2
double WN[NTOF]={0}; // captures in 3He target
double BN[NTOF][nwc]={{0}}; // N_i = N beta_i = \sum{n_i} ions
double GBN[NTOF][nwc]={{0}}; // M_i = N_i gamma_i = \sum{n_i gamma}
double D2N[NTOF][nwc][nwc]={{{0}}}; // delta^2 N_ij = covariance
double GW[NTOF][nwc]={{0}}; // weight of each element
// loop over events, fill "n","p2n" histograms, wc response matrices
if (ntp->GetEntries()<nev)
nev=ntp->GetEntries();
for (int iev=sev;iev<sev+nev;++iev)
{
if (verbose && cnt)
{ // :........:....
if (iev%(50*cnt)==0)
cout<<endl<<" :"<<flush;
else if (iev%(10*cnt)==0)
cout<<":"<<flush;
else if (iev%cnt==0) cout<<"."<<flush;
}
// read variables
ntp->GetEntry(iev);
hl5.Fill(l,p5*1.4/2*60);
n5 += p5;
hl6.Fill(l,p6*1.4/2*60);
// polarizer
float tx = 1; //Transmission
b_pol->GetEntry(iev);
if (pol!=pol)
pol=0; //nan
// choppers
for (int j=0;j<nch;++j)
{
float chw = chop[j]-ch_phi[j];
if (chw<0)
chw += 360;
if (chw>ch_open[j])
{
tx=0;
break;
}
}
if (tx==0)
continue;
hlc.Fill(l,p6*1.4/2*60);
// RFSF, averaged over spin sequence
float t_sf = (t6+(zsf-z6)/vz6)*freq;
static const float spin_seq_ave[]={1, -0.5, 0, 0.5, -1, 0.5, 0, -0.5};
if (psf==1 && (t_sf<rfsf_phi || t_sf>rfsf_phi+dsf))
continue;
if (t_sf!=0)
{
if (dsf<0)
{
pol*= spin_seq_ave[int(fabs(t_sf-rfsf_phi-0.5)+0.5)%8];
pol*=(1-cos(k_rfsf/vz6/(fmod(t_sf-rfsf_phi+10,1)+rfsf_phi)))/2.;
}
else
{
if (t_sf<rfsf_phi || t_sf>rfsf_phi+dsf) pol*=psf;
}
}
hls.Fill(l,p6*1.4/2*60);
// fill histograms for N,P2N
float dtev=(zwc-z6)/vz6, tev=fmod((t6+dtev)*freq, 1);
int it((tev*ntof+1)-1);
assert(it>=0 && it<ntof);
float n = p6 * tx;
N [it] += n;
P2N[it] += n * pol*pol;
// collimator
float xx=x6+vx6*(zwc-z6)/vz6;
if (xcol>0 && fabs(xx)>xcol/2)
continue;
float yy=y6+vy6*(zwc-z6)/vz6;
if (ycol>0 && fabs(yy)>ycol/2)
continue;
hlx.Fill(l,p6*1.4/2*60);
// simulate ion chamber response
float zev=dwc/2.;
for (int iz=0; iz<nz; ++iz, zev+=dwc)
{
dtev=(zev+zwc-z6)/vz6;
tev=fmod((t6+dtev)*freq, 1);
it = int(tev*ntof+1)-1;
assert(it>=0 && it<ntof);
float xev=x6+vx6*dtev, yev=y6+vy6*dtev;
float rhosig=rho3*ksig*l; // attenuation const and weight
float wza = (exp(-rhosig*zev)-exp(-rhosig*(zev+dwc)))*da/2*db/2/PI;
for (int ia=0; ia<na; ++ia)
{
cz=ccz[ia];
for (int ib=0; ib<nb; ++ib)
{
cx=ccx[ia][ib];
cy=ccy[ia][ib];
float d1=d1r, d2=d2r, d1t,d2t; // ionization range
// restrict ionization to active volume of wc
if (cz>0)
d1t=(z1w-zev)/cz, d2t=(z2w-zev)/cz;
else
d1t=(z2w-zev)/cz, d2t=(z1w-zev)/cz;
if (d1<d1t)
d1=d1t;
if (d2>d2t)
d2=d2t;
if (cx>0)
d1t=(x1w-xev)/cx, d2t=(x2w-xev)/cx;
else
d1t=(x2w-xev)/cx, d2t=(x1w-xev)/cx;
if (d1<d1t)
d1=d1t;
if (d2>d2t) d2=d2t;
if (cy>0)
d1t=(y1w-yev)/cy, d2t=(y2w-yev)/cy;
else
d1t=(y2w-yev)/cy, d2t=(y1w-yev)/cy;
if (d1<d1t)
d1=d1t;
if (d2>d2t)
d2=d2t;
if (d2<d1)
continue; // not in active volume
// iterate over ionized cells
float beta1, beta0=beta_fn(d1);
float wz=(z0w-zev)/cz, dwz=dzw/cz;
int jz((d1-wz)/dwz), djz=1;
if (jz==nwz)
--jz;
wz+=dwz*jz;
if (cz>0)
wz+=dwz;
else
dwz*=-1, djz*=-1;
float wx=(x0w-xev)/cx, dwx=dxw/cx;
int jx((d1-wx)/dwx), djx=1;
if (jx==nwx)
--jx;
wx+=dwx*jx;
if (cx>0)
wx+=dwx;
else
dwx*=-1, djx*=-1;
int k=0;
assert(0<=jz&&jz<nwz && 0<=jx&&jx<nwx);
while (0<=jz&&jz<nwz && 0<=jx&&jx<nwx)
{
kzx[k] = jz*nwx + jx;
if (d2<=wz && d2<=wx)
{
kbeta[k++]=beta_fn(d2)-beta0;
break;
}
if (wz<wx)
{
beta1=beta_fn(wz);
jz+=djz;
d1=wz;
wz+=dwz;
}
else
{
beta1=beta_fn(wx);
jx+=djx;
d1=wx;
wx+=dwx;
}
kbeta[k++]=beta1-beta0;
beta0=beta1;
}
// tabulate ion response
WN[it] += n*wza;
for (int i=0;i<k;++i)
{
float ni= n*wza*kbeta[i];
BN [it][kzx[i]] += ni;
GBN[it][kzx[i]] += ni*cxyz[geom_xyz];
for (int j=0;j<k;++j)
{
D2N[it][kzx[i]][kzx[j]] += ni*kbeta[j];
}
}
}
}
}
}
f->Close();
// calculate FOM=p2n, projection; draw both
double N_tot=0, P2N_tot=0, WN_tot=0, xd2a_tot=0;
for (int it=0;it<ntof;++it)
{
TMatrixDSym mat(nwc, &**D2N[it]);
if (verbose>3 && ntof==1)
{
cout<<"\n delta^2 N_ij :\n";
mat.Print();
}
// for (int i=0;i<nwc;++i) for (int j=0;j<nwc;++j) if (i!=j) mat(i,j)=0;
mat.Invert();
if (verbose>3 && ntof==1)
{
cout<<"\n delta^-2 N_ij :\n";
mat.Print();
}
double xd2a=0;
for (int i=0;i<nwc;++i)
{
for (int j=0;j<nwc;++j)
{
GW[it][i] += GBN[it][i]*GBN[it][j]*mat(i,j);
}
xd2a += GW[it][i];
}
N_tot += N[it];
P2N_tot+= P2N[it];
WN_tot += WN[it];
xd2a_tot += xd2a;
if (verbose > 2)
{
printf("\n beta_i:");
for (int i=0;i<nwc;++i)
{
if (!(i%nwx))
printf("\n ");
printf(" %9.5g",BN[it][i]/N[it]);
}
printf("\n\n gamma_i:");
for (int i=0;i<nwc;++i)
{
if (!(i%nwx))
printf("\n ");
printf(" %9.5g",GBN[it][i]/BN[it][i]);
}
printf("\n\n weight_i:");
for (int i=0;i<nwc;++i)
{
if (!(i%nwx))
printf("\n ");
printf(" %9.5g",GW[it][i]);
}
printf("\n\n");
}
if (verbose > 4)
{
printf("\n\n beta_i:");
for (int j=0;j<nwc;++j)
{
printf(" %9.5g",BN[it][j]/N[it]);
}
printf("\n\n beta_ij:");
for (int i=0;i<nwc;++i)
{
printf("\n ");
for (int j=0;j<nwc;++j)
{
printf(" %9.5g", D2N[it][i][j]/N[it]);
}
}
}
if (verbose>1 && ntof>1)
{
cout<<" N = "<< N[it] <<endl;
cout<<" <P^2> = "<< P2N[it] / N[it] <<endl;
cout<<" <W> = "<< WN[it] / N[it] <<endl;
cout<<" delta^-2 A = "<< xd2a*P2N[it]/N[it] <<endl;
cout<<" sigma_d = "<< sqrt(N[it] / xd2a) <<endl<<endl<<endl;
}
}
cout<<"All TOF bins combined"<<endl;
cout<<" N0 = "<< n5 <<endl;
cout<<" N = "<< N_tot <<endl;
cout<<" <P^2> = "<< P2N_tot/N_tot <<endl;
cout<<" <W> = "<< WN_tot / N_tot <<endl;
cout<<" delta^-2 A = "<< xd2a_tot*P2N_tot/N_tot <<endl;
cout<<" sigma_d = "<< sqrt(N_tot / xd2a_tot) <<endl;
return sqrt(N_tot / xd2a_tot);
}
