Archive | May 2016

Vertex-finding successes!

Here are a few (of many!) nice examples where you’ve collectively outperformed the reconstruction algorithms to find some Off-Centre Vertices in simulation.

Image 1 – AHH00002qz ‘zoom’


7 clicks from 7 people (marked with pale blue dots) form a cluster (orange dot at (420,590)) right on top of one the ‘truth’ (i.e. real, from simulation) OCVs (yellow dots) – well done!

Image 2 – AHH00002rw ‘normal’


Here 3 people have together identified both OCVs – the orange dots are hidden underneath the yellow ones since they’re spot on!

Image 2 –  AHH00006xk ‘slice’


Saving the best for last: a more complicated image, with a few ‘stray’ tracks complicating things. However, when combined the 28 clicks from 7 people form clusters bang on the simulated decay points! As an aside: the ‘weird’ clicks are marking the little coloured dots you often see in slice views – these are completely expected, and show the positions of all the proton-proton collisions that happened at the same time but at different positions along the beam pipe (which runs horizontally across the centre of the image).


It’s great to see you all doing such a good job at finding these OCVs, more analysis to follow!

Analysis time

With the 2016 LHC restart well under way, having successfully recovered from attacks by small mammals (BBC article), it’s time to start analysing your clicks in earnest! Over the past year and a half you’ve made more than half a million classifications (thank you!), and flagged a whole host of interesting features. Over the next few months we’ll be extending the work done by Thomas (e.g. here) on this enlarged dataset to see what we can find out! Stay tuned for more details, and keep on clicking – every image you look at is potentially an as-yet unseen event!