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Edgar Carrera | USLHC | USA

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Immediate rediscovery of physics

The CMS Collaboration has made public the preliminary plot that shows the di-photon resonance (pi0). Enjoy!!

Edgar Carrera (BU)

This entry was posted on Tuesday, March 30th, 2010 at 8:16 am and is filed under Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

12 Responses to “Immediate rediscovery of physics”

1. Nathan L says:

   March 30, 2010 at 1:02 pm

   Wikipedia tells me that the mass of the neutral pion is 135 MeV. What gives? Is the calibration off?

   Reply
2. Blake says:

   March 30, 2010 at 3:44 pm

   Cool! Congratulations! Why is the peak at 116 MeV and not 135 MeV, the rest mass of a Pi0? -A (curious) non-physicist

   Reply
3. Tom says:

   March 30, 2010 at 4:35 pm

   I’m no expert in physics but
   I’ve had ateast 1 upper diviSion course. What foes this mean?

   I’ve also noticed on a couple of the collision 3d screen grabs that the there’s an obvious red jet that’s not found in the other shots. Would you mind explaining this a bit. It would be really cool to see an annotated shot of a collision with small notes and perhaps equations and links to wikipedia or more details.

   One last question. Which technology and science areas do you and other scientists feel will be most influenced by the discoveries? Energy, computing, healthcare, etc… and why?

   Thanks a million!!! Exciting stuff!

   Reply
   • Edgar Carrera says:

     April 6, 2010 at 8:38 am

     Hi,
     If you are talking about this one, that is actually a muon in the endcaps.
     As far as the areas that will be influenced by our possible discoveries, I am sure Energy will be one for sure. Computing and healthcare have been already influenced directly and indirectly.

     -e
4. Stephen Brooks says:

   March 31, 2010 at 10:29 am

   Nice. What’s the next particle to find after pi0? The J/psi or maybe the W or Z?

   Reply
   • Edgar Carrera says:

     April 6, 2010 at 8:32 am

     Sure, J/psi, W, Z you name it, life will be even more exciting then..
5. vivek says:

   April 1, 2010 at 7:53 pm

   why is the mass so far from the nominal value? It is too low by almost 20 MeV!

   Reply
6. Carl Carly says:

   April 2, 2010 at 12:14 pm

   Why is the mass wrong?

   Reply
7. Curious says:

   April 4, 2010 at 9:26 am

   Why is the mass of the peak not at the known pi0 mass?

   Reply
8. Vivek Jain says:

   April 5, 2010 at 11:03 am

   Hi,

   I had left a comment last week, but I guess the easter weekend intervened. Also, I logged into the blog site, but don’t see my comment as pending, so I don’t know what happened.

   In any case, why is the mass of the pi0 off by 20 MeV? That seems kind of a large shift.

   vivek

   Reply
9. Edgar Carrera says:

   April 6, 2010 at 8:12 am

   Thanks a lot for all your comments. The reason why the mass is not death on on the nominal mass is because the plot was made with the “out of the box” tools. No corrections for clustering/containment are implemented in this plot. It is basically an on-line plot. One of the tasks for CMS experts right now is to fine-tune (calibrate) the detector, and for that these known resonances are extremely useful. The fact that we are so close to it “as is” is very encouraging.

   Reply
10. Sean Vostinar says:

    April 8, 2010 at 10:29 am

    Would you please describe the relationship between the plotted graph and the event display? Do the blue and red plots simply correspond to the Hcal and Ecal?

    Also, here’s a repost (it was new to me!) of a link that explains how to interpret the CMS event display.
    http://www.symmetrymagazine.org/breaking/2010/03/16/cms-event-display-decoded/

    Reply