instrumentation for particle and nuclear physics

www.helsinki.fi/yliopisto

Instrumentation for particleand nuclear physics

1Matemaattis-luonnontieteellinen tiedekunta / Fysiikan laitosEija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 17.5.2017


9:00–10:30 Lecture @ E205, Doc. Eija TuominenIntroduction to instrumentation andradiation detectors,Safe working in laboratory environment

10:30–11:00 Pause11:00-12:30 First laboratory exercise @B304/B306-308/AK10812:30-13:30 Lunch13:30-15:00 Second laboratory exercise @B304/B306-308/AK10815:00-15:30 Coffee15:30-16:30 Analysis of your laboratory exercises @ E205

2

Today’s Program

Matemaattis-luonnontieteellinen tiedekunta / Fysiikan laitosEija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 18.5.2017


1. Introduction to detectors and instrumentationA. Radiation detectors in instrumentationB. Types of radiationC. Operational principle of radiation detectors

2. Introduction today’s exercises at Detector LaboratoryA. Detector Laboratory in the instrumentation of physicsB. Description of the three exercisesC. Each student subscribes for two tasks out of three

3. Introduction to laboratory safety

3

Today’s Lecture



1.ARadiation Detectors in

Instrumentation


www.helsinki.fi/yliopisto 5

Radiation detectors are used inparticle physics experiments…

©CERN

proton-proton collider



©FAIR6

… nuclear physicsexperiments…

Heavy ion collider


www.helsinki.fi/yliopisto 7Matemaattis-luonnontieteellinen tiedekunta /Eija Tuominen / Radiation Detectors II / Lecture 1

… medical imaging …

©AJAT

©Medbroadcast

18.5.2017


… nuclear safety, security andsafeguards…

14.1.2014

©NDT

© Detection Technology

©TVO

Matemaattis-luonnontieteellinen tiedekunta / Fysiikan laitosEija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi


… AI, IoT, robotics...

https://www.linkedin.com/pulse/independent-elderlies-internet-things-use-case-arun-joe-joseph

https://www.ald.softbankrobotics.com/en/cool-robots/pepper/find-out-more-about-pepper



1.BTypes of Radiation



§ Radiation is energy travelling through space.§ We study detectors measuring ionizing radiation.

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What is Radiation?

http://serc.carleton.edu/NAGTWorkshops/health/case_studies/nuclear_cancer.html



Radiation occurs in forms of rays and particles:j

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Types of radiation

Charged particulate radiation: Fast electrons (β+, β-, e-)Heavy charged particles(ions; e.g. α, p+, fission products)

Uncharged radiation: Electromagnetic radiation(X-rays, gamma-rays)Neutrons(fast and slow neutrons)

18.5.2017

https://www.mirion.com/introduction-to-radiation-safety/types-of-ionizing-radiation/


§ The unit of radiation energy is electron volt (eV);§ 1 eV = kinetic energy gained by one electron when

accelerated through the potential difference of 1 V;§ Si unit: joule (J): 1 eV = 1,602*10-19 J§ The energy of X- or gamma-ray photon:

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ln hchE ==

h = Planck’s constant (6,626*10-34 Js)n = frequencyc = speed of light (3,00 *108 m/s)l = wavelenght

Matemaattis-luonnontieteellinen tiedekunta / Fysiikan laitosEija Tuominen: Semiconductor Radiation Detectors, Lecture 1

Radiation Energy

18.5.2017


§ The radioactivity of a source is given by thefundamental law of radioactive decay:

§ Historical unit of radioactivity: curie (Ci);1 Ci = 3,7*1010 disintegrations/s (~activity of 1g 226Ra)§ SI unit: becquerel (Bq) = 1 disintegration per second

=> 1 Bq = 2,703*10-11 Ci§ NOTE: disintegration rate ≠ emission rate

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Radioactivity

NdtdN

decay l-=N = number of radioactive nucleit = timel = decay constant

Matemaattis-luonnontieteellinen tiedekunta / Fysiikan laitosEija Tuominen: Semiconductor Radiation Detectors, Lecture 1 18.5.2017


Radiation Dose andDose Equivalent

http://www.radtrainonline.com/free/viewslide.asp?CourseID=39&ModuleID=167&SlideID=3011


§ Absorbed dose D is the mean energyabsorbed from any type of radiation perunit mass of the absorber.§ 1 gray (Gy) = 1 Joule/kg (=100 rad).

§ Dose equivalent H for a given type of radiationdescribes the biological damage created by radiation:

§ 1 sievert (Sv) (= 100 rem).§ Example: @Kumpula background gamma radiation

~13±1 mSv/h.

DQH =


1.COperational Principle of

Radiation Detectors



§ The operation off radiation detectors is based on theinteraction between the radiation to be detected andthe material of the radiation detector.§ The four major categories of radiation:

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Radiation Interactions

Charged Particulate Radiations Uncharged RadiationsHeavy charged particles

(characteristic distance ~10-5 m)Neutrons

(characteristic length ~10-1 m)Fast electrons

(characteristic distance ~10-3 m)X-rays & gamma rays

(characteristic length ~10-1 m)Interact through Coulomb force ”Catastrophic” interactions, with

nuclei and electrons

https://www.mirion.com/introduction-to-radiation-safety/types-of-ionizing-radiation/Matemaattis-luonnontieteellinen tiedekunta / Fysiikan laitosEija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 18.5.2017


§ The linear stopping power S, orspecific energy loss, for radiation indetector material is the differentialenergy loss dE in differential pathlength dx.

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Note the similar behavior @n ->c:minimum ionizing particles (mip)

Stopping Power

n = particle velocitye = electronic chargeze = particle chargeN = absorber number densityZ = absorber atomic number

úû

ùêë

é-÷÷

ø

öççè

æ--=-= 2

2

2

220

20

24

1ln2ln4cv

cv

IvmNZ

vmze

dxdES p

Bethe formula for p+, a and ions:

m0 = electron rest massc = speed of lightI = [experimental] average excitation and ionization

potential of the [specific] absorber

v<<c v->c≠ 0

18.5.2017


§ The range of particles of certain energy is a uniquequantity in a specific absorber material.§ Conceptual experiment:

t = thickness of the absorber materialI0 = Intensity of the particle beamI = Intensity of the detected particle beamRm = mean range (most commonly used)Re = extrapolated range

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Particle Range forheavy charged particles

§ Thus, the active thickness of energy dispersive radiationdetectors (i.e. measuring the particle energy) must be largerthan the particle range in the detector material.

counter

Transmissioncurve

18.5.2017


Particle Range, heavy particles,examples

Alphas in air: Alphas in different materials: Different particles in silicon:

18.5.2017


§ For electrons:

For the sameenergy, -dE/dx islower for electronsthan for heavyparticles =>electrons havelonger range.

Electrons:range vs. energyin silicon

Particle Range forelectrons & gamma rays

§ For electromagnetic radiation:te

II m-=0

Linear attenuation coefficient m is theprobability per unit path length that gamma-ray photon is removed from the beam.

18.5.2017


Simplified Detector Model

Interactionbetween radiationand detectormaterial createscharge Q that iscollected withElectric Field Eduring collectiontime tC.

Panja Luukka, Doctoral Thesis



§ In radiation spectroscopy, the object is to measurethe energy distribution of incident radiation.§ Charge is proportional to the energy of the radiation.§ The smaller the resolution R the better the detector

distinguishes radiations with close energies.§ The fluctuations result from drifts in detector

operation, random noise and statistical noise.

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Energy Resolution



Example,energy dispersive detectors


Am-241 energy spectrum measured by gas-filled beer-candetector constructed by students in Detector Laboratory.

http://chemistry.tutorvista.com/nuclear-chemistry/decay-rate.html

a42

42 += -

- YX AZ

AZ


Example,position sensitive detectors


§ Strip/pixelized pn-junction semiconductor detectors or micro-patterned gaseus detectors (MPGDs) are widely used to measureparticle tracks in particle physics experiments

Hitmap of a single antiprotonannihilation event generated in a300 µm silicon sensor, using theTimepix3 readout chip. Data taken inthe Dec2014 CERN/AEgIS beam test

campaign.


2.BYour Laboratory exercises @

Detector Laboratory



Detector Laboratory

Micronova TechTalk 27.11.2015Eija Tuominen / HIP Detector Laboratory 18.5.2017 27

Si GEMQA

§ Helsinki Detector Laboratory, joint effort by HIP and UH/Physics:- supports the instrumentation of particle and nuclear physics;- supports the education of physics and instrumentation;- participates in R&D projects with external funding.

§ Premises, equipment and know-how for research projectsdeveloping semiconductor and gas-filled radiation detectors;

§ Participation in the instrumentation is a pre-requisite to accessCERN & FAIR experiments and their measurement data toproduce new physics.


§ Two laboratories and a clean room;

§ Equipment for Research & Development (R&D), prototyping andQuality Assurance (QA);

§ Personnel with extensive know-how about semiconductor andgas-filled detectors and instrumentation.

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Infrastructureof Detector Laboratory



TASK: Radiation tolerance ofsemiconductor detectors

§ With Tatyana Arsenovich, Jennifer Ott,Laura Martikainen @B304.

§ Radiation gradually destroys the detectormeasuring it.

§ Radiation damage is typically analyzedby measuring electrical characteristics ofthe detector.

§ In pn-junction semiconductor detectors,the most important characteristics areleakage current from current-voltage (IV)measurement and depletion voltage fromcapacitance-voltage (CV) measurement.

§ Here, you study irradiated and non-irradiated silicon detectors with probestation.



TASK:Detector Data Acquisition (DAQ)

§ With Dr. Vladislav Litichevskyi, VillePykkönen @ B306-308.

§ Ionizing particle or electromagneticradiation generates charge carriers indetector material.

§ Here, you use appropriate dataacquisition system to collect andanalyze the electrical signals inducedby sealed radiation source andmeasured by GAGG:Ce scintillatordetector.



TASK: Quality Assurance (QA)of detector components

§ With Essi Kangasaho, FranciscoGarcia @ clean room AK108.

§ In physics experiments, the detectorsmust operate long periods trustworthywithout needs for maintenance.

§ Thus, the quality assurance ofdetectors and detector components isof outmost importance.

§ Here, you measure optical andelectrical characteristics of GEM (GasElectron Multiplier) foils that are basiccomponents in gas-filled detectors.

§ To avoid contamination, the detectorcomponents are kept in clean roomconditions.



3Laboratory Safety



WELCOME TO INSTRUMENTATION LABORATORY!

Matemaattis-luonnontieteellinen tiedekunta / Fysiikan laitosLab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 18.5.2017


WARNING SIGN EXPLANATIONS

IRRITANTHaitallinen/ärsyttävä/herkistävä/otsonikerrokselle haitallinen

TOXICVälittömasti myrkyllinen

FLAMMABLESyttyvä

POLLUTINGYmpäristölle vaarallinen

CORROSIVESyövyttävä

SEVERE HEALTH RISKVakava terveysvaara

GASES UNDER PRESSUREPaineen alaiset kaasut

RADIATIONSäteilyä

HIGH VOLTAGEKorkeajännite

SHARP EDGESLeikkautumisvaara

HIGH LEVEL OF NOISE



GENERAL LABORATORY SAFETY

• Do not use machinery without training.

• Always use the safety technology available.

• Materials storaging

• Chemicals and glues are stored in special air-conditionedcupboards.

• Tools and materials are stored in their own positions liketools walls and materials carousel.

• After usage

• Shut down the machines.

• Return tools and materials to their right places.

• Put trash in the right trash cans and recycling boxes.

• Clean up.

Tools wall

Materials carousel

Material recycling boxes

Chemical storage



LABORATORY SAFETY, FUME HOOD

• Fume hood is safety technology which is used to protect humans fromharmful fumes and dust.

• Example: glueing

• Do not store anything on the fume hood.

• Keep the fume hood clean.

• If you need to leave materials to fume hood;

• Place materials so, that others can use the fume hood during preservation.

• Mark your samples.

• Keep the fume hood door closed.

Fume hood



LABORATORY SAFETY, CHEMICALS

• The mostly used chemicals in the instrumentation laboratory are IPA (Isopropyl alcohol) and acetone.

• IPA and acetone are kept in special bottles with air-locks because of their flammability.

• Widely used glues (e.g epoxy) are harmful to health

• Skin contact: Danger of severe allergic reactions and poisoning.

• Eye contact: Danger of permanent eye-damages.

• Inhalation of glue fumes:

‒ Short term exposure; respiratory tract irritation and headache.

‒ Long term exposure; Allergic reactions and brain damages.

• Glueing safety

• Carry out glueing in fume hood.

• Follow carefully the glue package instructions.

• Use gloves.

• Protect your eyes from glue spreads.

• Use disposable tools when possible.

• Put the glue waste to glue waste box in plastic bag.

• Dry the glued matters in fume hood with closed door.

Eye damage first aid Emergency shower

Widely used araldite andepoxy glues



LABORATORY SAFETY, SOLDERING

• Soldering irons tip temperatures are in level 300°C-500°C.Hold the soldering iron on a right way.

• After usage clean up and shut down the soldering irons.

• Set the soldering irons to their holders on a right way.

• Do not store anything on soldering station.

Tip



LABORATORY SAFETY, SOLDERING

• Soldering process releases VOC (Volatile Organic Compounds) and possibly heavy metals (e.g lead) containing fume to air.

• Short term exposure; respiratory tract irritation, headache and allergy reactions

• Long term exposure; severe respiratory tract problems(e.g cancer and asthma), headache and allergy reactions.

• Soldering fumes are heavier than air. That is why special Fume Extraction Kit is needed to keep the soldering process safe.

• How to use the Fume Extraction Kit:

• Turn on the power from the switches 1 and 2.

• Turn on the power from the control panel 3. Adjust the fume intake power using – and + buttons.

• Maximum funnel distance D from the sample is 15cm.



LABORATORY SAFETY, GASES ANDMECHANICAL WORK

• Mechanical work

• Do not use upright drills.

• Use safety glasses, ear protection and if applicable: protective gloves.

• Gases: The most widely used gases in instrumentation laboratory arenitrogen and P10-gas (mixed gas with 90% Ar, 10% methane).

• Do not use gases without supervision.

• Do not handle gas bottles.

Upright drill

Gas valves



LABORATORY SAFETY, HIGHVOLTAGES AND CURRENTS

• High voltages and currents are present ininstrumentation laboratory.

• Follow carefully instructions of your supervisor!

ALICE project HV- technology



LABORATORY SAFETY, RADIATION

• Only low level sealed radiation sources are used in training cources.

• Follow the instructions of your supervisor.

• Radioactive sources usage, handling and storage conditions are regulated by law.

Radiation sources storages Radiation meters



Enjoy yourinstrumentation exercises!


instrumentation for particle and nuclear physics

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