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_episodes/01-jets101.md

@@ -52,10 +52,22 @@ Full set of intro slides: Slides 1-24 (FIXME)
   <center><figcaption>Parton showering    → Hadronization   → Jet of color neutral particles</figcaption></center>
 </figure>
 
-
+ * This give us a more generalised picture: _Almost everything becomes a jet: g/q/t/W/Z/H/PU_ 
 
 ### What is a jet?
 
+> ## Looking at an event display from our data
+> <img src="../fig/episode1/jets101_1.svg" alt="" style="width:50%">
+> How do you determine which particles are included in a jet?
+{: .discussion}
+
+From a list of particles one can form jets, an object to reconstruct the shower of particles produced from a quark or gluon. Each particle belonging to a jet is known as a constituent. Each has a 4-vector that can be used for further studies.
+
+We need a jet algorithm to collect the particles in a shower. This defines a __Clustering
+Algorithm__. This algorithm iteratively find the two particles in the event which are closest in some distance measure and combine them. Combine two particles if $d_{ij} < d_{iB}$. Stop when dij > diB.
+
+
+
 
 ### Exercise 1