Instrumentation for particle and nuclear physics

Transkriptio

1 Instrumentation for particle and nuclear physics Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

2 Today s Program 9:00 10:30 E205, Doc. Eija Tuominen 10:30 11:00 Pause Introduction to instrumentation and radiation detectors, Safe working in laboratory environment 11:00-12:30 First laboratory 12:30-13:30 Lunch 13:30-15:00 Second laboratory 15:00-15:30 Coffee 15:30-16:30 Analysis of your laboratory E205 Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 2

3 Today s Lecture 1. Introduction to detectors and instrumentation A. Radiation detectors in instrumentation B. Types of radiation C. Operational principle of radiation detectors 2. Introduction today s exercises at Detector Laboratory A. Detector Laboratory in the instrumentation of physics B. Description of the three exercises C. Each student subscribes for two tasks out of three 3. Introduction to laboratory safety Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 3

4 1.A Radiation Detectors in Instrumentation Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

5 Radiation detectors are used in particle physics experiments proton-proton collider CERN Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 5

6 nuclear physics experiments Heavy ion collider FAIR Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 6

7 medical imaging Medbroadcast Matemaattis-luonnontieteellinen tiedekunta / Eija Tuominen / Radiation Detectors II / Lecture 1 AJAT 7

8 nuclear safety, security and safeguards TVO NDT Detection Technology Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

9 AI, IoT, robotics com/en/cool-robots/pepper/findout-more-about-pepper Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 9

10 1.B Types of Radiation Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

11 What is Radiation? Radiation is energy travelling through space. We study detectors measuring ionizing radiation. Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 11

12 Types of radiation Radiation occurs in forms of rays and particles:j Charged particulate radiation: Fast electrons (β +, β -, e - ) Uncharged radiation: Heavy charged particles (ions; e.g. α, p +, fission products) Electromagnetic radiation (X-rays, gamma-rays) Neutrons (fast and slow neutrons) ntroduction-to-radiationsafety/types-of-ionizingradiation/ 12

13 Radiation Energy 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: E = hn = hc l h = Planck s constant (6,626*10-34 Js) n = frequency c = speed of light (3,00 *10 8 m/s) l = wavelenght Eija Tuominen: Semiconductor Radiation Detectors, Lecture

14 Radioactivity The radioactivity of a source is given by the fundamental law of radioactive decay: dn dt decay = - ln N = number of radioactive nuclei t = time l = decay constant Historical unit of radioactivity: curie (Ci); 1 Ci = 3,7*10 10 disintegrations/s (~activity of 1g 226 Ra) SI unit: becquerel (Bq) = 1 disintegration per second => 1 Bq = 2,703*10-11 Ci NOTE: disintegration rate emission rate Eija Tuominen: Semiconductor Radiation Detectors, Lecture

15 Radiation Dose and Dose Equivalent Absorbed dose D is the mean energy absorbed from any type of radiation per unit mass of the absorber. 1 gray (Gy) = 1 Joule/kg (=100 rad). Dose equivalent H for a given type of radiation describes the biological damage created by radiation: H = DQ 1 sievert (Sv) (= 100 rem). background gamma radiation ~13±1 msv/h. rainonline.com/ free/viewslide. asp?courseid =39&ModuleID =167&SlideID= 3011 Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 15

16 1.C Operational Principle of Radiation Detectors Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

17 Radiation Interactions The operation off radiation detectors is based on the interaction between the radiation to be detected and the material of the radiation detector. The four major categories of radiation: Charged Particulate Radiations Heavy charged particles (characteristic distance ~10-5 m) Fast electrons (characteristic distance ~10-3 m) Interact through Coulomb force Uncharged Radiations Neutrons (characteristic length ~10-1 m) X-rays & gamma rays (characteristic length ~10-1 m) Catastrophic interactions, with nuclei and electrons Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 17

18 Stopping Power The linear stopping power S, or specific energy loss, for radiation in detector material is the differential energy loss de in differential path length dx. Bethe formula for p +, a and ions: = de 4pe z Ø 2m0v v v S - = NZ Œln - ln dx m º Ł ł 2 0v I c c n = particle velocity e = electronic charge ze = particle charge N = absorber number density Z = absorber atomic number m 0 = electron rest mass c = speed of light I = [experimental] average excitation and ionization potential of the [specific] absorber ø œ ß 0 v<<c Note the similar ->c: minimum ionizing particles (mip) v->c 18

19 Particle Range for heavy charged particles The range of particles of certain energy is a unique quantity in a specific absorber material. Conceptual experiment: counter Transmission curve t = thickness of the absorber material I 0 = Intensity of the particle beam I = Intensity of the detected particle beam R m = mean range (most commonly used) R e = extrapolated range Thus, the active thickness of energy dispersive radiation detectors (i.e. measuring the particle energy) must be larger than the particle range in the detector material. 19

20 Particle Range, heavy particles, examples Alphas in air: Alphas in different materials: Different particles in silicon: 20

21 For electrons: Particle Range for electrons & gamma rays Electrons: range vs. energy in silicon For electromagnetic radiation: I I 0 = e -mt For the same energy, -de/dx is lower for electrons than for heavy particles => electrons have longer range. Linear attenuation coefficient m is the probability per unit path length that gammaray photon is removed from the beam. 21

22 Simplified Detector Model Panja Luukka, Doctoral Thesis Interaction between radiation and detector material creates charge Q that is collected with Electric Field E during collection time t C. Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 22

23 Energy Resolution In radiation spectroscopy, the object is to measure the 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. Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 23

24 Example, energy dispersive detectors Am-241 energy spectrum measured by gas-filled beer-can detector constructed by students in Detector Laboratory. A Z X = - Y - A Z a Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 24

25 Example, position sensitive detectors Strip/pixelized pn-junction semiconductor detectors or micropatterned gaseus detectors (MPGDs) are widely used to measure particle tracks in particle physics experiments Hitmap of a single antiproton annihilation event generated in a 300 µm silicon sensor, using the Timepix3 readout chip. Data taken in the Dec2014 CERN/AEgIS beam test campaign. Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 25

26 2.B Your Laboratory Detector Laboratory Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

27 Detector Laboratory 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 projects developing semiconductor and gas-filled radiation detectors; Participation in the instrumentation is a pre-requisite to access CERN & FAIR experiments and their measurement data to produce new physics. Si QA GEM Micronova TechTalk Eija Tuominen / HIP Detector Laboratory 27

28 Infrastructure of Detector Laboratory Two laboratories and a clean room; Equipment for Research & Development (R&D), prototyping and Quality Assurance (QA); Personnel with extensive know-how about semiconductor and gas-filled detectors and instrumentation. Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi 28

29 TASK: Radiation tolerance of semiconductor detectors With Tatyana Arsenovich, Jennifer Ott, Laura Radiation gradually destroys the detector measuring it. Radiation damage is typically analyzed by measuring electrical characteristics of the detector. In pn-junction semiconductor detectors, the most important characteristics are leakage current from current-voltage (IV) measurement and depletion voltage from capacitance-voltage (CV) measurement. Here, you study irradiated and nonirradiated silicon detectors with probe station. Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

30 TASK: Detector Data Acquisition (DAQ) With Dr. Vladislav Litichevskyi, Ville B Ionizing particle or electromagnetic radiation generates charge carriers in detector material. Here, you use appropriate data acquisition system to collect and analyze the electrical signals induced by sealed radiation source and measured by GAGG:Ce scintillator detector. Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

31 TASK: Quality Assurance (QA) of detector components With Essi Kangasaho, Francisco clean room AK108. In physics experiments, the detectors must operate long periods trustworthy without needs for maintenance. Thus, the quality assurance of detectors and detector components is of outmost importance. Here, you measure optical and electrical characteristics of GEM (Gas Electron Multiplier) foils that are basic components in gas-filled detectors. To avoid contamination, the detector components are kept in clean room conditions. Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

32 3 Laboratory Safety Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

33 WELCOME TO INSTRUMENTATION LABORATORY! Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

34 WARNING SIGN EXPLANATIONS IRRITANT Haitallinen/ärsyttävä/herkistäv ä/otsonikerrokselle haitallinen SEVERE HEALTH RISK Vakava terveysvaara TOXIC Välittömasti myrkyllinen FLAMMABLE Syttyvä CORROSIVE Syövyttävä POLLUTING Ympäristölle vaarallinen GASES UNDER PRESSURE Paineen alaiset kaasut RADIATION Säteilyä HIGH VOLTAGE Korkeajännite SHARP EDGES Leikkautumisvaara HIGH LEVEL OF NOISE Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

35 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-conditioned cupboards. Tools and materials are stored in their own positions like tools 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. Materials carousel Chemical storage Tools wall Material recycling boxes Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

36 LABORATORY SAFETY, FUME HOOD Fume hood is safety technology which is used to protect humans from harmful 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 Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

37 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. Widely used araldite and epoxy glues Eye damage first aid Emergency shower Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

38 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 Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

39 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. Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

40 LABORATORY SAFETY, GASES AND MECHANICAL 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 are nitrogen 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 Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

41 LABORATORY SAFETY, HIGH VOLTAGES AND CURRENTS High voltages and currents are present in instrumentation laboratory. Follow carefully instructions of your supervisor! ALICE project HV- technology Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

42 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 Lab.ins. Pirkitta Koponen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi

43 Enjoy your instrumentation exercises! Eija Tuominen, Hiukkasfysiikan kesäkoulu 2017 / Instrumentointi