calc_lum (ul_physlib)

	luminosity.r4.v = calc_lum(lattice.s.r, particle_param.s.r,
			           int_lower_bnd.r4.v, int_upper_bnd.r4.v)

	This routine numerically integrates the luminosity over the
	longitudinal variable z.  The routine qromb_p in PHYSLIB
	is used for the integration.
	See ul_physlib:calc_lum.h for definition of data types.

	lattice		structure of type LATT_PARAMS containing the
			lattice parameters at z = 0
	particle_param 	structure of type PARTICLE_PARAMS  containing 
			other parameters:  the x and y labels refer to the
			tranverse horizontal and vertical planes, respectively.
			The 1 and 2 labels refer to the proton and antiproton
			bunches, respectively.
	int_lower_bnd   lower limit of integration (meters)
	int_upper_bnd   upper limit of integration (meters)	

	This function returns values as follows:

	-1.0			error occurred
	otherwise		luminosity (cm**-2 sec**-1)

	This function requires the following include files:

	ul_physlib_h:calc_lum_h

	Related functions:

	calc_sigma, emitt_dp, qromb_p