Loading in 2 Seconds...
Loading in 2 Seconds...
Detectors & Measurements: How we do physics without seeing…. Overview of Detectors and Fundamental Measurements: From Quarks to Lifetimes. Prof. Robin D. Erbacher University of California, Davis. References : R. Fernow, Introduction to Experimental Particle Physics, Ch. 14, 15
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Overview of Detectors and
From Quarks to Lifetimes
Prof. Robin D. Erbacher
University of California, Davis
References: R. Fernow,Introduction to Experimental Particle Physics, Ch. 14, 15
D. Green, The Physics of Particle Detectors, Ch. 13
Lectures from CERN, Erbacher, Conway, …
A Higgs field interacts
as well, giving particles
The SM states that:
The world is made
up of quarks and
leptons that interact
35 times heavier
than b quark
Lepton Masses:Me<M<M ; M~0.*
Quark Masses:Mu ~ Md < Ms < Mc< Mb << Mt
Rare Events, such as Higgs production, are difficult to find!
Need good detectors, triggers, readout to reconstruct the mess into a piece of physics.
Cartoon by Claus Grupen, University of Seigen
No single detector does it all…
Create detector systems
Fixed Target Geometry
Modern detectors consist of many different pieces of
equipment to measure different aspects of an event.
Measuring a particle’s properties:
Particles are detected via their interaction with matter.
Many types of interactions are involved, mainly electromagnetic.
In the end, always rely on ionization and excitation of matter.
Jet (jet) n. a collimated spray of high energy hadrons
Quarks fragment into many particles to form a jet, depositing energy in both calorimeters.
Jet shapes narrower at high ET.
Signature Detector Type Particle
Jet of hadrons Calorimeter u, c, tWb,
d, s, b, g
‘Missing’ energy Calorimeter e, ,
shower, Xo EM Calorimeter e,, We
interactions, dE/dx Muon Absorber ,
Decays,c ≥ 100m Si tracking c, b,
(TOF, C, dE/dx)
vParticle Identification Methods
Constituent Si Vertex Track PID Ecal Hcal Muon
electron primary — —
Photon primary — — — —
u, d, gluon primary — —
Neutrino — — — — — —
s primary —
c, b, secondary —
primary — MIP MIP
MIP = Minimum
Z bosons have a very short lifetime, decaying in ~10-27 s, so that only decay particles are seen in the detector. By looking at these detector signatures, identify the daughters of the Z boson.
But some daughters can also decay:
More Fun with Z Bosons, Click Here!
Run 2 Event
+ Large homogeneous field inside
- Weak opposite field in return yoke - Size limited by cost
- Relatively large material budget
+ Field always perpendicular to p
+ Rel. large fields over large volume + Rel. low material budget
- Non-uniform field
- Complex structural design
Two ATLAS toroid coils
Superconducting CMS Solenoid Design
All silicon: pixels and strips!
210 m2 silicon sensors
6,136 thin detectors (1 sensor)
9,096 thick detectors (2 sensors)
9,648,128 electronics channels
All silicon sensors:
using tungsten with Si wafers
Coming next time…