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Explore observational astronomy, telescope alignment, and CMS detector study in astrophysics projects for teachers. Gain hands-on experience with the Celestron 8-inch telescope and CMS detector components. Learn how to analyze events from the Compact Muon Solenoid and interpret particle tracks. Dive into particle physics research involving Top Quark, LeptoQuark, and Standard Model Higgs. Understand the detection of prompt photons and weak boson exchange in high-energy collisions. Utilize CMS public data for real-world analysis and data interpretation.
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Research Education for Teachers Summer 2013 Caroline Fletcher Advisor: Dan Karmgard
Projects • Astrophysics • Compact Muon Solenoid
Astrophysics • Observational Astronomy • Telescope alignment • Celestron 8-inch. • Image taking • SBIG ST-8XECCD camera and attached it to the Celestron CPC800 11-inch Schmidt-Cassegrain telescope.
Cartoon Muon Solenoid Program: • Components: • Image • This is a three dimensional image of the Compact Muon Solenoid (CMS) detector. • Can rotate and view every inch of the detector while studying the variety of events. CMS
Graphic Controls • Controls the transparency of each detector part. • Detectable Path • This is the actual physics. (The vector sum of Transverse momentum in the x-y plane) CMS
Event type • EM: Electrons/Positrons/Photons • These stop in the Ecal • HD: Charged pions/neutral kaons • These stop in the Hcal • Mu: Muons/Neutrions • These travel through the entire detector. • Charge • Determines the shape of the track. • 0 = straight line • -1/+1 bend in the opposite direction. • Px/Py/Pz • The charge determines the direction and the momentum determines the amount of curvature. • This will only occur in the x-y plane due to the solenoid being oriented along the z-axis. • Vertex • Where the collision occurred (0 cm) CMS
Underlying Event • This allows you to see EVERYTHING!! (HELP ME) • AvgBkg • The average background value is used as the average of a flat distribution. • Lower number = less realistic • PtCut • This filter allows you to concentrate on the transverse momentum. • Higher momentum = less tracks • Track • Number assigned to each track. • Color • This enables you to “pin-point” the exact track you wish to study when concentrating on momentum. • Help and Home • Self explanatory! CMS
Particle Identification • Color Code • Since tracks are generated without your interaction, colors have been assigned to particle type • Electrons = Green • Photons = Light Blue • Hadrons = Yellow • Muons = Red • Neutrinos = Dark Blue CMS
Track information • Hold shift and left mouse together, and a box will appear. • pz = Momentum on the z-axis • pT = Transverse Momentum • φ = Angular displacement • ɳ = Efficiency • VTX = Vertex • M = Mass • E = Energy • ID = Particle CMS
pT Cut (MeV) = 0 • Hard Quantum Chromodynamics (QCD) • Hadron-Hadron collisions and predicted by the perturbation theory. • Fragment into jets. pT Cut (GeV) = 5
pT Cut (MeV) = 0 • Top Quark • The heaviest of all six which makes it very short lived. • The been has to be at least 7 TeV. • Decay into W-boson and a bottom quark. pT Cut (GeV) = 5
LeptoQuark • Hypothetical Particle (Do I need to say more?) • pp collisions with energies around 7 TeV. Being heavy, these particles decay very quickly into one of three generations. pT Cut (MeV) = 0 pT Cut (GeV) = 5
Standard Model (SM) Higgs • This particle has no spin, electric charge, or color change with mass around 125 GeV/c2. • Unstable = Quick Decay • Many believe that this particle explains why some particles are massive and others mass-less. • Most probable decays: • b-quark-b-antiquark, charmed quark-charmed antiquark, or tau-anti-tau. • Other possibilities: • WW and ZZ, although these particles will also undergo another stage of decay (lepton-anti-lepton, neutron-anti-neutron, quark-anti-quark)
pT Cut (MeV) = 0 pT Cut (GeV) = 5
Prompt Photons • pp collisions and are detected in the eCal. • Because they do not fragment into jets, we can achieve a more accurate picture of these photons. • Two processes • Low pT • The quark gluon Compton Scattering process dominates. • High pT • Quark anti-quark annihilation dominates. • As the curves steepness decreases, the pTwill increases.
pT Cut (GeV) = 5 pT Cut (MeV) = 0
Weak Boson Exchange • W and Z particles that are the carrier of the electromagnetic force. • We only see the decay particles! • There are 24 possibilities with only 21 that are visible. • Most common: quark-antiquark pair which you can see as jets.
pT Cut (MeV) = 0 pT Cut (GeV) = 5
pT Cut (GeV) = 5 Single pT Cut (MeV) = 0
pT Cut (MeV) = 0 Boson Pair pT Cut (GeV) = 5
pT Cut (MeV) = 0 Boson + Jet pT Cut (GeV) = 5
CMS public data (The REAL thing!!!!) • How to choose your data set • Select data file: Choose which type of event you would like to research. • Event: Public released data usually in sequential order. • Muon Filters: • Tracker is the inner most part of the detector, and the muons that are detected in this section produce ambiguous results in all other parts of the detector. • Stand Alone: This type of muon is detected in the spectrometer and has no detection in the tracker. These muons are more than likely produced from a decay and are also accompanied with a jet. • Global: This type of muon is measured in all sections of the detector.
Jet cones: The cones indicate that there are many particles traveling together in the same direction away from the same source. This is also a sign that a quark collision may have just occurred. You may check this box for on/off view. • Jet Hadrons: • Quarks or Gluons have been knocked out of the proton.