added introduction

docs/io/visualization/montecarlo_packet_visualization.ipynb

@@ -7,6 +7,14 @@
     "# Montecarlo Packet Visualization"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "This visualization tool plots the `RPackets` that are generated by the [Montecarlo](https://tardis-sn.github.io/tardis/physics/montecarlo/index.html) method and creates an animated plot that contains the packet trajectories as they move away from the photosphere.\n",
+    "The properties of individual RPackets are taken from the [rpacket_tracker](https://tardis-sn.github.io/tardis/io/output/rpacket_tracking.html). "
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
@@ -88,8 +96,11 @@
     "<br><br>The diagram above shows the packet trajectory as it starts from photosphere `P0` and continues to move along the subsequent points `P1`, `P2` and so on.\n",
     "\n",
     "<div class=\"alert alert-info\">\n",
-    "    <b>Note:</b><br>\n",
-    "    Here μ is the angle of direction of packet propagation with respect to line joining the center.\n",
+    "\n",
+    "Note\n",
+    "    \n",
+    "Here `μ` is the angle of direction of packet propagation with respect to line joining the center.\n",
+    "    \n",
     "</div>\n",
     "\n",
     "To determine the polar coordinates of any arbitrary point, let say `P2`, we need `r2` and `θ2`. `r2` is already present in the array obtained from the simulation. To determine `θ2`, we use sine rule and apply it on triangle `OP1P2`, where `O` is the center.\n",