A few ways to bring particles into your classes and to your students

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A few ways to bring particles into your classes and to your students. With thanks to Ken Cecire from QuarkNet . QuarkNet.fnal.gov has been around since some time. About this breakout session. Why : you are the best ambassadors of particle physics, as you knead the dough of the future. - PowerPoint PPT Presentation


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A few ways to bring particles into your classes and to your studentsWith thanks to Ken Cecire from QuarkNet.April 2014a.david@cern.ch - #CERNPhil20141QuarkNet.fnal.gov has been around since some timeApril 2014a.david@cern.ch - #CERNPhil20142

About this breakout sessionWhy: you are the best ambassadors of particle physics, as you knead the dough of the future.What: introduce you to particle physics resources and activities that you can do with your students.How: go through two QuarkNet activities.Introduction 10Quark puzzle activity 40Plotting LHC discovery activity 40Perchance chat with Ken.April 2014a.david@cern.ch - #CERNPhil20143ResourcesThe International Particle Physics Outreach Group (IPPOG): http://ippog.web.cern.ch/QuarkNet: http://quarknet.fnal.gov/

April 2014a.david@cern.ch - #CERNPhil20144What we will look at todayQuark Puzzlestudents fit quark "pieces" togetheruse to learn about quark combination rules to form mesons and baryons with electrical charge, color charge, matter-antimaterpuzzle "workbench" and pieces (must be cut out) at http://leptoquark.hep.nd.edu/~kcecire/mclib/files2012/QW_puzzle.pdf instructions at http://leptoquark.hep.nd.edu/~kcecire/mclib/files2012/Quark_Instructions.pdf Plotting LHC Discoverystudents construct J/Psi mass plot from data, identify peak and backgroundstudents then examine a discovery plot from LHC (e.g. 4 July 2012) and pick out similar featuresdescription for students at http://quarknet.us/library/upload/7/73/Discoveryplots_student.pdfdescription for facilitator at http://quarknet.us/library/upload/0/0e/Discoveryplots_tchr.pdf

April 2014a.david@cern.ch - #CERNPhil20145Quark puzzleConcepts:Compositeness of matter at the lowest levels.Hadrons: mesons vs. baryons.Symmetries imply rules for composition.Charges come in many flavours.

April 2014a.david@cern.ch - #CERNPhil20146Pieces to put togetherApril 2014a.david@cern.ch - #CERNPhil20147

Quark puzzleHands-on partApril 2014a.david@cern.ch - #CERNPhil20148April 2014a.david@cern.ch - #CERNPhil20149

April 2014a.david@cern.ch - #CERNPhil201410

Plotting LHC discoveryConcepts:Peaks imply correlations.Quantities that are invariant.Discoveries are declared at some level of significance.April 2014a.david@cern.ch - #CERNPhil201411

This is not pretend scienceOn November 10, 1974, SLAC's Burton Richter and colleagues found evidence for a particle they called the (the Greek letter Psi). Meanwhile on the east coast of the United States, Samuel Ting and his colleagues found comparable evidence for a particle they called the J.Both were the same particle and papers from both groups were published in Physical Review Letters on 2 December, 1974, as the first evidence for what is now known as the J/. Richter and Ting were jointly awarded the Nobel Prize in Physics in 1976 for the discovery, a mere two years after the work was done.April 2014a.david@cern.ch - #CERNPhil201412http://cern.ch/go/S8S7

Its the dawn of an exciting age of new discovery in particle physics!

At CERN, the LHC and its experiments are tuning up.

CMS the Compact Muon Solenoid has been taking data. Our job is to understand how the detector responds to data from a known Standard Model particle in the 7 TeV run from 2010.The LHC and New Physics13The LHC is buried ~100 m below the surface near the Swiss-French border.

The LHC and New Physics14Generic DesignCylinders wrapped around the beam pipeFrom inner to outer . . . Tracking Electromagnetic calorimeter Hadronic calorimeter Magnet*Muon chamber

* location of magnet depends on specific detector design Detectors

1515 Detectors21st April 2008Fergus Wilson, RAL16

The beam particles each have a total energy of 3.5 TeV:2 x 3.5 TeV = 7 TeV*The individual particles that make up the proton only have a fraction of this energy. New particles made in the collision always have a mass smaller than that energy.

Proton Interactions* This was the energy in the 2010 run. It has since been increased to 8 TeV.1717Particle DecaysThe collisions create new particles that promptly decay. Decaying particles always produce lighter particles.

Conservation laws allow us to see patterns in the decays.

Can you name some of these conservation laws?

Particle DecaysOften, quarks are scattered in collisions.

As they separate, the binding energy between them converts to sprays of new particles called jets. Muon signals can come from jets.

They are not what we are looking for.

We are studying the J/Y, a particle with no charge that decays into two muons.

What do we know about the charges of the muons? What is the charge of the J/Y?

Particle Decays

Particle DecaysAn event with two oppositely charged muons might be a decay of the particle that we are interested in.

It might also be something else.

CMS Mass Plot of Z boson

Histogram ReviewWell-defined peak Outliers: lower frequency Where is the peak?What is the width?Is the mass precise?

Histogram ReviewWhere is the peak?What is the width?Where are the outliers?Not all histograms have same precision

Histogram ReviewTwin peaks: Poor definition of one signal orTwo signalsIn particle physics, could be:Two separate particles orLarge signal as "background" and smaller bump showing actual particle under study.

Higgs at LHCApril 2014a.david@cern.ch - #CERNPhil201426

Another peak: B0s+-April 2014a.david@cern.ch - #CERNPhil201427

Context for plot at: http://www.flickr.com/photos/uslhc/8182573711/ .The materialsApril 2014a.david@cern.ch - #CERNPhil201428

Plotting LHC discoveryHands-on partApril 2014a.david@cern.ch - #CERNPhil201429More activitiesCMS Data Expressa "short form" of the CMS masterclass measurement that can be accomplished in 1-2 hours and is relatively easy to usehttps://quarknet.i2u2.org/document/cms-data-express

CMS e-Labrather more involved; users can make mass plots and other histograms from relatively large sets of CMS data; login as guest; I can create accounts for those who want to get investigate further for use with students. http://www.i2u2.org/elab/cms

April 2014a.david@cern.ch - #CERNPhil201430Wrap-upThere are lots of resources out there to inspire your students.If you want to know more about this, drop us a line.Ken is available to help you with the materials/activities: kcecire@nd.eduApril 2014a.david@cern.ch - #CERNPhil201431


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