NAME:
surfacemassLOS
PURPOSE:
evaluate the 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)
OPTIONAL INPUT:
nsigma - number of sigma to integrate the velocities over
KEYWORDS:
target= if True, use target surfacemass (default)
romberg - if True, use a romberg integrator (default: False)
deg= if False, l is in radians
OUTPUT:
Sigma(d,l)
HISTORY:
2011-03-24 - Written - Bovy (NYU)