double BCAL_tdiff_res(double geometric_mean, int ilayer)
{
	double &x = geometric_mean;
	switch(ilayer){
		case 1:
			return -0.194707+(0.000934194/(pow(x,0.000273634)-1.00026));
			break;
		case 2:
			return 0.636055+(85658/(pow(x,2.8606)+19951.7));
			break;
		case 3:
			return 100.0;
			break;
		case 4:
			return 100.0;
			break;
		case 5:
		case 6:
		case 7:
		case 8:
		case 9:
		case 10:
			return 100.0;
	}

	return 1000.0;
}