PIGE experience in IPPE

Institute of Physics and Power Engineering, Obninsk, Russia

A.F. Gurbich

Overview

• For the analysis of carbon, sodium, aluminum, and chromium resonance PIGE was employed. The excitation functions for the corresponding reactions were measured in the vicinity of resonances favorable for analytical applications.

• The oxygen analysis using gammas from direct non-resonant radiative capture was undertaken.

• PIGE was used for the analysis of various samples including semiconductor structures and nuclear reactor materials.

• Hydrogen analysis using resonance 1H(19F,)16O reaction was used to study hydrogen penetration into coating layers on the surface of zirconium pipes.

• Propagation of the spectrometer efficiency calibration on the high energy region was made using cascade gamma quanta from the resonance 27Al(p,)28Si reaction with known gamma ray branching.

• Tickonov’s regularization method was applied to resolve the ill-posed problem of the determination of concentration on depth distribution.

• Pulsed incident beam was used to substantially enhance the sensitivity of the PIGE analysis due to suppression of the background gamma-radiation.

Experimental facilities

Thick target yield for resonance

The resonance yield per unity solid angle and unity incident particles charge for prompt gamma-rays emission from homogenous target with energy thickness of ET is defined as

where N0 - is Avogadro constant, A - is a molecular mass, c - is element concentration in the target.

Assuming the Breit-Wigner resonance

where R - is a cross section at resonance energy ER and - is a resonance width,

the yield for an infinitely thick target (ET>>) is

The R, , and ER may be regarded as free parameters and these have to be found by fit of theoretical yield

to measured data.

Y cN

A

p

dE dxdE

E E

E

T

0 ( , )

/,

( , )/

( )

p

E ER

R

2

22

4

4

YcN

A dE dx

E ER R 0 1

2 2 2

/

( tan/

)

Thick target yield for the 23Na(p,p’)23Na reaction (E=439 keV) in the vicinity of the resonance and its theoretical description

− Bodart F., Deconninck G., Demortier G. Quantitative analysis of sodium by (p,)-reactions. J. Radioanal. Chem. 35 (1977) 95

− This measurement (target – NaCl, detector – Ge(Li), proton beam from the EG-2.5 Van de Graaff accelerator of IPPE)

Deduced resonance parameters ER=1456 1.8 keV and =8.30.8 keV

Thick-target yield of gamma rays from the 27Al(p,)28Si reaction

1000 1200 1400 1600 18000

100

200

300

400

12549 12742 12935 13128 13321

Ex, keV

E= 9-11 MeV

27Al(p,)28Si

G

am

ma

-Ra

y Y

ield

, R

el. U

nits

Ep, keV

Resonance energies are indicated by bars

Thick target yield of -rays at the 991.9 keV resonance in the 27Al(p,)28Si reaction

Proton energy, keV

− Deconninck G., Demortier G. Quantitative analysis of aluminium by prompt nuclear reactions. J. Radioanal. Chem. 12 (1972)189.− This measurement

PIGE analysis of carbon

0

200

400

600

800

(а)

Ep=550 кэВ

=2452 кэВ

12C(p,)13N=2366 кэВE

Emax

N

2000 2100 2200 2300 2400 2500 26000

2

4

6(б)

Энергия гамма-квантов

Intense resonances in the reaction 12С(p,)13N (Q=1944.010.22 keV) are observed at 0.457 and 1.699 MeV.

For the Еp= 457 keV resonance (total

width Г=35 keV, resonance cross-section =127 mb) the ray energy is 2.366 MeV.

For the Еp = 1.699 MeV resonance

(total width Г=70 keV, resonance cross-section =35 mb) the -ray energy is 3.51 MeV.

Gamma ray energy

(b)

keV

keV

keV

(a) – graphite

(b) – steel (~0.1% of carbon concentration)

Excitation function of the 52Cr(p,)53Mn reaction

From R.L.Schulte et al. Nucl. Phys. A243 (1975) 202

Thick target yield of -rays at the 1005 keV resonance in the 52Cr(p,)53Mn reaction

Proton energy, keV

The IAR at Еp = 1005 keV decays mainly through the levels at 2.87 MeV (26%) and 3.18 MeV (20%) whereas the contribution of all other resonances in population of these levels is small. Thus measured spectra contain gamma quanta which are specific only for this resonance.

Gamma-ray spectrum (high energy part) for the decay of the IAR at Ep=1005 keV in the 52Cr(p,)53Mn reaction

1200 1400 1600 1800 20000

20

40

60

80

10052Cr(p,)53Mn

2804

keV

20%R 3182 keV

2497

keV

26%R 2875 keV E

p=1020 keV

Ep=1000 keV

Cou

nts/

Cha

nnel

Channel Number

Gamma-ray spectrum (low energy part) for the decay of the IAR at Ep=1005 keV in the 52Cr(p,)53Mn reaction

100 200 300 4000

1000

2000

3000

52Cr(p,)53Mn

378 keV

511 keV

Ep=1020 keV

Ep=1000 keV

Cou

nts/

Cha

nnel

Channel Number

Oxygen analysis using gammas from direct non-resonant radiative capture

( ) ( ( ))E E E constp p E EM

M mE x Q E Ep p ( ) ( )

1

N E EN

Mq c x E E x E x

xAp p( , ) ( ) ( ( ( ))) ( ( ), )

cos

Co

unt

s/C

han

nel

Channel Number

The resonance parameters for the 1H(19F,)16O reaction

ER, MeV , keV Peak value

6.418 44.1 1675

9.121 17.1 669

11.198 575 2954

12.583 80.1 3867

15.686 105.5 3039

16.441 85.4 69847

17.634 152.9 38201

The gamma ray yield for the 1H(19F,)16O reaction. The EXFOR data for the 19F(p,)16O reaction were converted for the case when 19F is a

projectile

6000 8000 10000 12000 14000 16000 18000 200000

100

200

300

400

500

600

1H(

19F,)16

O

0.1

Ga

mm

a R

ay

Yie

ld, a

rbitr

ary

un

its

Energy, keV

A typical spectrum of gamma quanta from the 1H(19F,)16O reaction measured with a NaI(Tl) detector at

the 19F2+ beam energy of 9.2 MeV

0 50 100 150 200 250 300 350 4000

300

600

900

1200

1500

NaI(Tl) 160150 mm1H(19F,)16O E = 6.13 MeV

Co

un

ts/C

ha

nn

el

Channel Number

The spectrum of gamma rays for the 27Al(p,)28Si reaction from which the spectrometer efficiency for high energy

gamma quanta was determined

2 1 2

1 2 1

,I S

I S

Branching for a resonance in the 27Al(p,)28Si reaction at Ep=767 keV

0 1 2 3 4 5 6 7 8 9 101

10

100

Ep=767 кэВ

27Al(p,)28Si

Pro

babi

lity

for

emis

sion

, %

-ray energy, MeV

12

.32

3

4.6

17

Me

V

4.6

17

1

.77

9 M

eV

Solid line – E=7.706 MeV

Dashed line – E=2.873 MeV

Angular distribution

)(cos)(cos1)( 4422 PAPAW

Resolving inverse problem using the regularization method

The gamma ray yield The derived hydrogen profile

In order to derive the concentration on depth distribution c(x) the Fredholm

equation of the first kind

should be resolved. This ill-posed problem was resolved using Tickonov’s

regularization method.

dxxEFxcEYx

max

0

00 ,)(

Gamma-ray yield for the aluminized steel sample

1000 1100 1200 1300 1400 1500 1600 17000

5000

10000

15000

20000

25000

30000

35000

Гам

ма-

выхо

д (

отн.

ед

.)

Ep, кэВ

Dots – experiment

Line – theoretical fit

Yie

ld,

arbi

trar

y un

its

keV

27Al(p,28Si

Block diagram of the electronics

Pre-amplifier

LogicShaper

Delay

Pre-amplifier

Detector

Spectro-scopic

Amplifier

DifferentialDiscrim.

FastAmplifier

ConstantFraction

Discr.

Time toAmplitudeConverter

Analog toDigital

Converter

stopstart

t

E

TargetPick-up

strobe

Energy and timing spectra

Channel Number (Energy) Channel Number (Time)

Cou

nts/

Cha

nnel

Cou

nts/

Cha

nnel

Tar

get

Slit

s

0.75 ns/channel

Characteristics of the reactions used for PIGE analysis of the BN-600 atomic power plant steam generator wall

Reaction -ray energy, MeVResonance energy, MeV

Proton beamenergy

Depth resolution,m

Maximal depth, m

12C(p,o)13N 2.366 0.457 0.5 0.2 4

16O(p,1)17F 16/17Ep(x)+0.105 0.8 0.04 3

23Na(p,)20Ne 1.634 1.011 1.011-1.070 0.016 0.6

23Na(p,p’)23Na 0.440 1.283 1300 0.07

52Cr(p,)53Mn 0.378 1.005 1.005-1.080 0.05 0.8

Sodium distribution near the surface of an oxidized silicon wafer

The insert shows a part of gamma-spectrum around the sodium line at E=439 keV for oxidized () and virgin () samples for irradiation with a proton beam of Ep=1470 keV

mas

s %

m

PIGE analysis of a semiconductor laser structure

p- эмиттер

p - Ga 1-x Al x As

Активный слойp - GaAs

n - эмиттер

n - Ga 1-x A lxAs

Подслой

n - GaAs

Подложка

~1мкм

~0.2 мкм

4 - 5 мкм

4 - 5 мкм

980 1000 1020 1040 1060 1080 1100 1120 1140

300

350

400

450

500

550

600

650

N(Ep)

Поверхность

~0.2 мкм

~0.8 мкм

Ep , кэВSubstrate

Sub-layer

n-emitter

Active layer

p-emitter

Surface

keV

~1 m

~0.2 m~0.2 m

4-5 m

4-5 m

m

m

Aluminum depth profile near surface of the samples tested in the flow of melted lead. Solid line – results obtained using 27Al(d,p0+1)28Al reaction. Dashed line – PIGE results.

0.25

0.30

0.35

0.40

0.45

0.0

0.1

0.2

0.3

0.4

0.0

0.1

0.2

0.3

0.4

0 1 2 30.0

0.1

0.2

0.3

Virgin

Ato

mic

Con

cent

ratio

n

2000 hours

3000 hours

4000 hours

Depth, m

Mistakes in PIGE data presentation in IBANDL

PIGE data presentation in IBANDL

PIGE data problems

2200 2250 2300 2350 2400 2450

2

4

6

8

10

12

14

16

18

Mateus et al. Caciolli et al.

Cro

ss-s

ect

ion

, mb

Proton energy, keV

23Na(p,p'1-0)23Na

Atomic Energy Review Supplement No.2 (1981)

J.R. Bird, M.D. Scott, L.H. Russel, M.J. Kenny, Analysis using Ion Induced Rays. Aust. J. Phys., 31 (1978) 209.