NAME:
targetSurfacemassLOS
PURPOSE:
evaluate the target surface mass along the LOS given l and d
INPUT:
d - distance along the line of sight
l - Galactic longitude (in deg, unless deg=False)
deg= if False, l is in radians
log - if True, return the log (default: False)
OUTPUT:
Sigma(d,l)
HISTORY:
2011-03-23 - Written - Bovy (NYU)