Merge pull request #366 from eblur/colorexcess_math_fix

fix math rendering on color excess tutorial

Author: eblur

tutorials/notebooks/color-excess/color-excess.ipynb

@@ -116,6 +116,7 @@
     "$$\n",
     "\\frac{dF_\\lambda}{F_\\lambda} = -\\tau_\\lambda\n",
     "$$\n",
+    "\n",
     "where $\\tau$ is the optical depth and depends on wavelength.  Integrating along the line of sight, the resultant flux is an exponential function of optical depth,\n",
     "$$\n",
     "\\tau_\\lambda = -\\ln\\left(\\frac{F_\\lambda}{F_{\\lambda,0}}\\right).\n",
@@ -125,6 +126,7 @@
     "$$\n",
     "\\tau_\\lambda = -2.303\\log\\left(\\frac{F_\\lambda}{F_{\\lambda,0}}\\right),\n",
     "$$\n",
+    "\n",
     "and define an extinction $A_\\lambda = 1.086 \\,\\tau_\\lambda$ so that\n",
     "$$\n",
     "A_\\lambda = -2.5\\log\\left(\\frac{F_\\lambda}{F_{\\lambda,0}}\\right).\n",
@@ -168,6 +170,7 @@
     "$$\n",
     "R_V \\equiv \\frac{A_V}{E_{B-V}}\n",
     "$$\n",
+    "\n",
     "where $E_{B-V}$ is differential extinction $A_B-A_V$.  In this example, we show the $R_V$-parameterization for the Clayton, Cardelli, & Mathis (1989, CCM) and the Fitzpatrick (1999) models. [More model options are available in the `dust_extinction` documentation.](https://dust-extinction.readthedocs.io/en/latest/dust_extinction/model_flavors.html)"
    ]
   },
@@ -557,6 +560,7 @@
     "$$\n",
     "A = -2.5\\log\\left(\\frac{\\int W_\\lambda F_{\\lambda,0} 10^{-0.4A_\\lambda} d\\lambda}{\\int W_\\lambda F_{\\lambda,0} d\\lambda} \\right),\n",
     "$$\n",
+    "\n",
     "where $W_\\lambda$ is the fraction of incident energy transmitted through a filter.  See the detailed appendix in [Bessell & Murphy (2012)](https://ui.adsabs.harvard.edu/#abs/2012PASP..124..140B/abstract)\n",
     " for an excellent review of the issues and common misunderstandings in synthetic photometry.\n",
     "\n",