details of Orsay Q-value calculation

Ebeam = initial beam energy (80 MeV)
Tbeam = real T of beam just before reaction
TinitResid = initial energy of ¹⁸O
TinitPF1,2 = initial alpha energies
Tflight... = energy after passing through target, dead layer of E detector, and poss. dE detector

double Qtrue=-(Tbeam-TinitResid-TinitPF1-TinitPF2); //this is the real god-given Q value of the reaction
double px=Math.sqrt(2*beam.A*Ebeam);//"x" is direction of beam
double p1=Math.sqrt(2*projfrag.A*TflightPF1);
double p2=Math.sqrt(2*projfrag.A*TflightPF2);
double px1=p1*Math.cos(Math.toRadians(thetaCalc1));
double px2=p2*Math.cos(Math.toRadians(thetaCalc2));
double py1=p1*Math.sin(Math.toRadians(thetaCalc1));
double py2=p2*Math.sin(Math.toRadians(thetaCalc2));
double pxresid=px-px1-px2;
double pyresid=py1+py2;
double Eresid=(pxresid*pxresid+pyresid*pyresid)/(2*18);//the residual will always be assumed to be ¹⁸O; for contaminants, it will obviously be something else really, but this is the Q-value we'll get
double Qcalc = -(Ebeam-TflightPF1-TflightPF2-Eresid); // this is the best way of calculating the Q value
double Qcalc2 = -(Ebeam-TflightPF1-TflightPF2-TflightResid); // using the measured ¹⁸O energy gives worse resolution