Further topics in spectroscopy γ-spectroscopy

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1 0 0 0

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E / ke V

0 5 0 0 1 0 0 0 1 5 0 0

2 2 6 R a 2 1 4 P b

K α

2 1 4 B i

γ-Spectroscopy with the scintillation counter • Detection of γ-rays • Spectra of different isotopes • Positron-Annihilation • Exponential intensity decay in matter• Compton-effect • Observing coincidence • β-Spectroscopy

For further information please ask your local salesperson

X-ray-spectroscopyX-ray energy detector 559 938

X-ray-spectroscopy with the X-ray energy detector • Detection of x-rays • Direct measurment of the x-ray

spectrum • Energy selective reflection in Bragg

configuration • X-ray fluorescence • Material analysis • Identification of alloys • Compton effect

N2

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E / keV

0 10 20 30

K α(M

o)

L α(A

u)

L β(A

u)

L α(T

a)

L β(T

a)

Kα(A

g)

Kβ(

Ag)

Kβ(

Mo)

Kα(M

o)

A g

M o

T aExperiments:

- X-ray spectrum- Compton effect

- Duane Hunt- Moseley’s law

- X-ray fluorescence- Material analysis

559

56_A

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trosc

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10.1

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LD Didactic GmbH • Leyboldstr. 1 • D-50354 Huerth • Germany • Phone: +49 2233 604-0 • Fax: +49 2233 604-222 • email: info@ld-didactic.de • www.ld-didactic.com

α-Spectroscopy with the semiconductor detector

Physics of the Atom

2 ⏐ LD Didactic

Classic Rutherford scattering • very few particles are scattered, but scattering

occurs even at large angles • The atom consist of a large hull and a small,

compact nucleus The semiconductor detector Digital mode with discriminator and counter, similar toa GM tube Analog mode for spectroscopy and measurements with an oscilloscope: • Different pulseheights with different preparations • Using radium-226 shows different pulseheights

Quantity Description Cat. No. 1 Rutherford scattering chamber 559 56 1 Aluminium foil in mount 559 52 1 Discriminator preamplifier 559 931 1 Plug-in power unit 230 V 562 791 or 1 Plug-in power unit 115 V 562 792 1 Am-241-preparation 559 821 1 Counter P 575 451 1 Vacuum pump D2.5E 378 752 1 Flange DN 16 KF 378 031 1 Vacuum rubber tubing 307 68 2 BNC cable, 1 m 501 02

559 56Rutherford scattering chamber Cylindrical vacuum chamber in which the scattering of particles at thin metal foils can be easily demonstrated both quantitatively and qualitatively. Also suitable for experiments on alpha spectroscopy. With axial rotary transmission leadthrough for swivelling the preparation and foil holder, and angle scale for a defined setting. • Angle scale (swivel range):

- 150° via 0° to + 150° mit 5°-division • Vacuum tube connection: 9 mm dia. • Measurement connection: BNC socketScope of delivery: 1 Vacuum chamber 1 Alpha detector with detachable slit screen 1 Slit screens1/2/5 mm 1 Gold foil in holder

559 931 Discriminator preamplifier Suitable for operation with solid-state detector (559 92) and Rutherford scattering chamber (559 56). Analog output with pulses, which are proportional to the energy for differential α energy spectra. Digital discriminator output with integral discriminator connected downstream for recording square-wave pulses, supplied by particles whose energies lie above an adjustable threshold.• Analog output:

Polarity of the pulses: negative Pulse duration: approx. 4.5 µs Pulse amplitude: approx. 0.05 V to 2 V

• Digital output: TTL • Supply voltage:

9 V d.c. to 20 V d.c.; 25 mA via MCA box or plug-in power supply

• Connections: Semiconductor detector -BNC socket

575 451 230 V 575 451NA 115 V Counter P For counting of GM tube pulses, pulse rates or other electrical pulses as well as for frequency and time measurement. With 5-digit LED display, internal loudspeaker. Plug-in power supply unit included. Further counters are available see: www.ld-didactic.com

Physics of the Nucleus α-spectroscopy Energy resolved measurements allow: • Identification of nuclides • Tracing decay chains on the chart of nuclides • Observation of energy loss in matter and air • Understanding radiation protection • Measure the density of matter • Range of α-radiation • Dating by radioactive isotopes • Fine-structure of nuclei level

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50

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E / keV

0 1000 2000 3000 4000 5000 6000 7000 8000 9000

226Ra

222Rn210Po

218Po 214Po

667 7061 Chart of the Nuclides Contains more than 2700 experimentally observed isotopes for all the 112 currently known elements with their corresponding half-life, decay mode and energy of the most important emitted radiation; A0 - size 667 7063 Book for Chart of the Nuclides 24 pages, A4, with folded inlay chart and detailed explanations for the use of the chart of the isotopes; in English, German, French and Spanish.

524 058 MCA box The MCA box is part of the CASSY-S system and together with suitable detectors (e.g. NaJ(Tl) scintillation counters, Si semiconductor detectors, X-ray energy detector) and in combination with Sensor-CASSY (524 013), CASSY Lab (524 220) and a computer, it constitutes a multi-channel pulse-amplitude analyzer for a fast and easy recording of the spectra of radioactive decay products. The MCA box contains a BNC input which allows the connection of external detectors, e.g. a NaJ scintillation counter (559 901) with detector output stage (559 912) or a semiconductor detector (559 92) or from (559 56) with discriminator-preamplifier (559 93). The voltage supply for the discriminator preamplifier (559 93) and the detector output stage (559 912) can be obtained from the MCA box via a multi-pin socket. The software CASSY Lab (524 220) permits the recording of measured values (including high-voltage measurement), the display and evaluation of any spectra in parallel. Energy calibration can be done with one or two known energies • Resolution: from 256 to 2048 channels (8-11 bits) per spectrum • Storage depth: 2 x 109 events per channel (31 bit) • Dead time: approx. 60 µs

Spectroscopic measurements are best done invacuum. With slight losings they can beperformed in air, therefore the semiconductordetector is available seperately (559 92)

For detecting α-radiation Quantity Description Cat. No. 1 Semiconductor detector 559 52 or 1 Rutherford Scattering chamber 559 56 1 Vacuum pump 1 Discriminator preamplifier 559 931 1 BNC cable, 0.25 cm 501 01 1 BNC cable, 1 m 501 02 1 Multicore cable, 6-pole 501 16 1 MCA box 524 058 1 Sensor-CASSY, 230 V 524 013 or 1 Sensor-CASSY, 115 V 524 013NA 1 CASSY Lab 524 220 as radiation source: 1 AM-241 preparation 559 821 1 Ra-226 preparation 559 435 additionally required: PC with Windows

LD Didactic ⏐ 3