Physics 780.20: Detector Physics

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Physics 780.20 Detector Physics
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General Information

• General Information
• Time Monday, Wednesday 1230 - 218 PM
• Location PRB 3041
• Lecturer Prof. Klaus Honscheid
• Course Website http//www-physics.mps.ohio-state.
  edu/klaus/s12-780/phys780.html
• Assessment
• Homework problems                                 
                                          (20)
• (short) paper with a presentation to the
  class                                 (40)
• Hands-On Measurement of the Muon Lifetime (if
  possible)         (40) 
• Textbook
• We will not follow any particular text book.
  However, most material covered in lecture (and
  more) can be found in any of these recommended
  resources.
• Techniques for Nuclear and Particle Physics
  Experiments, W.R. Leo, Springer
• Particle Detectors, 2nd ed., Grupen and Schwartz,
  Cambridge university Press
• The Physics of Particle Detectors, Dan Green,
  Cambridge University Press
• The Review of Particle Physics
• Free - request a copy at pdg.lbl.gov
• Detector sections
• As you might know, the world wide web was
  invented by particle physicists so it's not
  surprising that there is a lot of information on
  detector physics available on the net. Some of
  these links can be found in the reference section
  of these web pages.

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Syllabus

• Introduction
• Organizational Issues
• Some basic concepts and examples
• Radioactive sources, Accelerators
• General Characteristics of Detectors
• Passage of Radiation through Matter
• Scintillation Detectors, Photomultipliers
• Pulse Signals, Electronics for Signal Processing
• Trigger Logic, Coincidence Technique, Time
  Measurements
• Gaseous Detectors
• Ionization Counters
• Proportional Chambers
• Drift Chambers and Time Projection Chambers
• Streamer Chambers
• Silicon Detectors
• Principles
• Strip and pixel detectors
• Silicon Photomulitiplier
• CCDs

• Calorimetry
• Electromagnetic Calorimeters
• Hadronic Calorimeters
• Cryogenic Detectors
• Particle Identification
• Time of Flight
• Cherenkov Effect and Detectors
• Transition Radiation Detectors
• Muon Identification, Momentum Measurement
• Neutron Detection
• (Neutrino Detectors)
• Data Analysis
• Data Acquisition
• Simulation
• Statistical Treatment of Experimental Data
• Applications and Examples
• Student Presentations

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Projects

• Muon Lifetime Measurement
• Individual Projects

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Particle Physics In 1 Slide
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Detector Basics

• To be detected a particle has to live long enough
  to reach the detector
• Particle Lifetimes (see PDG for precise values
  and errors)
• Electron e- 0.511 MeV gt 4.6 x 1026 years
• Muon m- 105.6 MeV 2.2 x 10-6 seconds
• Tau t- 1777 MeV 2.9 x 10-13 seconds
• Neutrinos n lt eV gt 1020 seconds
• Quarks u, d, c, s, t, b no isolated quarks
• Proton p (uud) 938.2 MeV gt 1029 years
• Neutron n (udd) 939.6 MeV 881.5 seconds (free)
• Pion p (ud) 139.6 MeV 2.6 10-8 seconds
• p0 (uu,dd) 135.6 MeV 1.6 10-17 seconds
• Kaon K (us) 493.7 MeV 1.2 10-8 seconds
• K0 (uu,dd,ss) 497.7 MeV 5.1 10-8 s, 9.0 10-11 s

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Detector Basics

• To be detected a particle has to interact with
  the detector
• Particle Interactions
• Electron e- weak, electromagnetic
• Muon m- weak, electromagnetic
• Neutrinos n weak
• Proton p weak, electromagnetic, strong
• Neutron n weak, electromagnetic, strong
• Pion p weak, electromagnetic, strong
• Kaon K (us) weak, electromagnetic, strong
• K0L weak, electromagnetic, strong
• Photon g electromagnetic

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Detector Basics
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Particle Physics Conventions

• Energies are measured in eV (MeV, GeV, TeV)
• 1 eV 1.6 x 10-19 J
• A particles momentum is measured in MeV/c
• A particles mass is measured in MeV/c2
• Using E mc2 for an electron
• me 9.1 10-31 kg
• Ee me c2 9.1 x 10-31 (3x108)2 kg m2/s2
  8.2 10-14 J 0.511 MeV

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Muons Always good for a surprise
Time called the muon a winner !
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Cosmic Rays
p
Energies from 106 1020 eV
Courtesy Mats Selen
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Consider exotic violent events in the Cosmos as
noted by very energetic cosmic rays

• Record energy is a proton of 3x1020 eV (48 J) 
• Equivalent energy of a
• Roger Clemens fastball,
• Tiger Woods tee shot,
• Pete Sampras tennis serve,
• speeding bullet.

And, all just one proton
WHERE ARE THE COSMIC ACCELERATORS OF SUCH
PARTICLE FASTBALLS ???
Courtesy Tom Weiler, Vanderbilt University
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p
About 200 ms per square meter per second at sea
level. (lots of neutrinos too)
Courtesy Mats Selen
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Some typical values

• Cosmic Ray Flux on the surface
• Mostly muons, ltEgt 4 GeV
• Intensity 1 cm-2 min-1 for a horizontal
  detector
• Neutrino Flux
• Solar Neutrinos
• 6.5 x 1010 cm-2 min-1 (perpendicular to
  direction to sun)

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With the right instrument we can detect muons and
other particles

• Plastic scintillator
• Gives off a flash of light when a charged
  particle pass through

oscilloscope
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A typical physics class might

• catch some muons from cosmic rays,
• and, measure how long they live
• Answer 2 millionths of a second

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How is the muon lifetime measured?
N1
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How is the muon lifetime measured?
N10
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How is the muon lifetime measured?
N100
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How is the muon lifetime measured?
N100
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How is the muon lifetime measured?
N104
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How is the muon lifetime measured?
N106
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How is the muon lifetime measured?
N1012
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How long will it take?

• 1012 events necessary for 1 ppm measurement
  (relative error 1/vn)

Time to 1012
Muon rate
Source
m
104 years
1 / 50 cm2 s 1 / hand s
Cosmic rays
e
Scint.
PMT
p
1.6 years beam time
20 kHz
Continuous beam
m
PMT
PMT
Water
e
3 weeks beam time
(usable)
Pulsed beam
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Muon Lifetime Experiment
Goals Measure the lifetime of the muon (m) to
2 precision Gain hands-on experience with
detectors, electronics, data Break up into
groups of 2 or 3 Each group spends a few days
with the experiment in Smith Lab Report written
using LATEX (Develop your scientific writing
skills) template provided Report should include
a section on Introduction Apparatus Theory
calculation of muon lifetime Discussion of
higher order correction Lifetime of free m
Vs captured m Data Analysis Determination of
average m lifetime Possible separation into
m and m- lifetimes Upper limit on the amount
of a particle with lifetime4ms in data
Background estimation Systematic
errors Conclusions References Reports are due
before end of the winter quarter
This is a typical senior lab experiment. Search
the Web for lots of information on muon lifetime
measurements
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Projects

• Muon Lifetime Measurement
• Individual ProjectsWhile many of the detector
  concepts that we will discuss in this course have
  first been developed for particle and nuclear
  physics experiments, these instruments are now
  used for a large variety of applications.Your
  task
• Identify an interesting detector application
• Research this topic using the web, the library,
  local resources in the physics department
• Write a 5-10 page report in the style of a
  research paper
• Prepare a 20-30 minute presentation on your paper
  and the application you have investigated
• The next set of slides should give you some ideas

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Example Projects

• Homeland Security
• James BondIf you think a device that resembles a
  cellular phone but detects a potential nuclear
  threat and transmits a description of the nuclear
  material to every nearby crisis center sounds
  like something out of a James Bond movie, you are
  in for a surprise. Since the 1930s, when
  scientists first used the Geiger counter,
  radiation detection equipment has gone through an
  amazing evolution in size, sensitivity,
  deployability, and power.(From DOE web site)
• Baggage ScannersConventional x-ray baggage
  scanners in airports employ a dual energy x-ray
  approach in order to view different materials. A
  new approach has been employed to increase the
  identification of materials. This involves
  performing x-ray diffraction analysis on baggage
  as it passes through the scanner.
• Scanning Trucks (e.g. Neutron Activation Analysis)

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Example Projects

• CVD Diamond Detectors
• Developed by our own Harris Kagan
• Extremely radiation hard Beam monitor
  applications

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Example Projects

• Imaging Cherenkov Detectors
• Cherenkov Correlated Timing Detector
• BaBar DIRC
• Belle TOP

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Example Projects

• Neutrino Detectors
• Principles
• Minos, Nova
• Reactor Experiments
• Deep Underground Detectors
• SNO
• DUSEL
• Direct Dark Matter Searches
• Example Super Kamiokande

Put far underground(2700m H2O) to shield
against cosmic rays
40 m
Mt. Ikeno
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Some neutrino facts

• The Sun produces many neutrinos when it burns
• The Big Bang left us 300 neutrinos per cubic cm
  that are still running around
• Power reactors make lots of neutrinos
• ALL neutrinos are very hard to detect.
• Need enormous mass to catch just a few
• Fill space between the earth and sun with lead
• Less than 1 out of 10,000 neutrinos would notice!

Courtesy Mats Selen
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Put far underground(2700m H2O) to shield
against cosmic rays
Linac cave
Entrance 2 km
Control Room
Tank
Water System
Inner Detector
Outer Detector
Mt. Ikeno
The Super Kamiokande Detector
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13000 large PM Use a boat for maintance
installation Be careful
Nov. 13 2001 Bottom of the SK detector covered
with shattered PMT glass pieces and dynodes. 1/3
of PM destroyed
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2002 Nobel Prize Neutrino Oscillation results
from SuperK
Cosmic Ray protons illuminate the earth evenly
from all directions.
These produce lots of ns when they crash into
Earths atmosphere.
Super-K studied these atmospheric neutrinos as a
function of direction
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Half as many are observed from below as from above
It means they morph and it means they have
mass All Textbooks have now had to be rewritten
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Example Projects

• Instrumentation for Space Based Experiments
• GLAST/FERMI
• SNAP/JDEM

A high energy physics experiment in space Study
g-rays from 20 MeV-300 GeV Measure energy and
direction Dark matter annihilation Gamma ray
bursters Active Galactic Nuclei
ACD Segmented scintillator tiles 0.9997 efficiency
Si Tracker pitch 228 µm 8.8 105 channels 12
layers 3 X0 4 layers 18 X0 2 layers
CsI Calorimeter Hodoscopic array 8.4 X0 8
12 bars 2.0 2.7 33.6 cm

• cosmic-ray rejection
• shower leakage
• correction

size 1.8x1.8x1m
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Example Projects

• Bolometers Analyzing the Cosmic Microwave

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Example Projects

• Application of Particle Detectors in Medical
  Imaging Devices
• SPECT Camera
• Compton Camera
• PET
• Combined PET/MRI Scanner

Hot Topic PET-MRI
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Projects

• Muon Lifetime Measurement
• Individual Projects, List of Topics
• Detectors for Homeland Security
• Diamond Detectors
• Monte Carlo Simulation
• Trigger and Data Acquisition
• Combined PET/MRI Scanner
• Instrumentation for (Synchrotron) Light Sources
• Digital Calorimeter
• Bolometer
• Compton Camera
• Cherenkov Detectors using Total Internal
  Reflection
• Radiation Hardness
• New Photon Detectors (APD, Silicon PM etc)
• Detectors for Astrophysics (GLAST, Auger,
  Veritas)
• Deep Underground Detectors (Dusel)
• Neutrino Detectors
• Electronics, FPGA
• Cryogenic Detectors

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References used today

• Measurement of the Positive Muon Lifetime to 1
  ppm, D. Webber
• Worlds Greatest Scientific Instruments, D.
  Herzog
• Experimental Techniques of High Energy, Nuclear,
  AstroParticle Physics, R. Kass