Скачать презентацию Measurement of neutron emission spectra and activation in Скачать презентацию Measurement of neutron emission spectra and activation in

035871a8b08fe444094ce3de352ec6f3.ppt

  • Количество слайдов: 43

Measurement of neutron emission spectra and activation in Li, Be, C, Al, Fe, Ta(d, Measurement of neutron emission spectra and activation in Li, Be, C, Al, Fe, Ta(d, n) reactions by in the 20 -40 Me. V region M. Baba, M. Hagiwara, T. Itoga, T. Aoki Cyclotron & Radioisotope Center, Tohoku University , Japan M. Sugimoto Japan Atomic Energy Research Institute, Tokai Establishment, Japan T. Muroga, National Institute for Fusion Research, Toki, Japan ****CONTENTS******* 1. Introduction 2.  Apparatus & Experimental Methods    3. Results; Neutron spectra & Activation 4.  Summary

1. INTRODUCTION n In IFMIF ・ Neutron spectrum extends beyond 50 Me. V (High 1. INTRODUCTION n In IFMIF ・ Neutron spectrum extends beyond 50 Me. V (High energy tail) ・ Neutrons show very strong angular dependence ・ Beam intensity is as high as 250 m. A  Design & maintenance of IFMIF require the data on   ・ Energy-angular distribution of (d, n) neutrons; Li, accelerator structural elements   ・ Production/ accumulation of radioactive nuclides   3 H , 7 Be, 22 Na, 24 Na etc  Experimental data were very few and discrepant

INTRODUCTION(2) 7 Li(d, n) TTY;  M. A. Lone et al.  Nucl. Instrum. and Methods INTRODUCTION(2) 7 Li(d, n) TTY;  M. A. Lone et al.  Nucl. Instrum. and Methods 143 (1977) 331 -344 * Large discrepancies, Energy range is limited

In this study 1. Neutron spectrum from thick, thin targets of - Li, Be, In this study 1. Neutron spectrum from thick, thin targets of - Li, Be, C, Al, Fe, Ta   - @ 25, 40 Me. V - 0 -110 -deg. ・Comparison with exp. , calculations ・Systematics vs mass 2. Radio-nuclide production - Li, Be, C, Al, Fe, (Ta) - 7 Be, 22 Na, 24 Na, etc    

2. Experimental Apparatus Cyclotron & Radioisotope Center, Tohoku University (CYRIC) Layout of CYRIC Beam chopper 2. Experimental Apparatus Cyclotron & Radioisotope Center, Tohoku University (CYRIC) Layout of CYRIC Beam chopper Beam swinger Flight path Performance of K=110 AVF cyclotron • Protons 10 -90 Me. V • Deuterons 10 -65 Me. V • 3 He 20 -170 Me. V • 4 He 20 -130 Me. V ・Heavy Ions ・Beam Chopper    etc. Automated-irradiation apparatus Online-mass separator Semiconductor Irradiation apparatus

CYRIC TOF Line Beam-swinger & Well collimated TOF channel Beam-swinger system Setup detectors at CYRIC TOF Line Beam-swinger & Well collimated TOF channel Beam-swinger system Setup detectors at two locations

Vertical view of neutron course Vertical view of neutron course

TOF Measurement Copper Mesh(-500 V) MCS 3 parameter list mode ・ 2 -gain ・ TOF Measurement Copper Mesh(-500 V) MCS 3 parameter list mode ・ 2 -gain ・ 2 -flight path

Radio-nuclides production deuteron neutron spectrum meas. After TOF measurement, γ-ray measurement with Ge detector Radio-nuclides production deuteron neutron spectrum meas. After TOF measurement, γ-ray measurement with Ge detector   4 -1. SETUP 4 -2. γ-ray spectrum Sample HV+4000 V Ge detector γray 19 cm Amp MCA

TOF data processing low-gain raw data n-event n- discrimination [channel] Pulse height [channel] high-gain TOF data processing low-gain raw data n-event n- discrimination [channel] Pulse height [channel] high-gain raw data n-event n- discrimination [channel]

Derivation of neutron spectrum 1. n-γdiscrimination 2. Bias setting ; ~ 0. 6 Me. Derivation of neutron spectrum 1. n-γdiscrimination 2. Bias setting ; ~ 0. 6 Me. V for high-gain, ~ 3. 5 Me. V for low-gain 3. TOF to energy spectrum m 0 I L c : Rest mass of a neutron : Channel number of the events : Flight path : Light velocity. 4. Absolute scale; detector efficiency,solid-angle, current 5.       (SCINFUL-R code). 5. Corrections for attenuation in target (air: LA 150) 6. just stopping length to avoid excessive correction

Radionuclide production (1) Beam fluctuation with MCS 1) Reaction rate 2) Number of products Radionuclide production (1) Beam fluctuation with MCS 1) Reaction rate 2) Number of products 3) Activity : decay constant (s-1), C : total counts of gamma-ray peak area, : peak efficiency, Tc : cooling time (s), : branching ratio of gamma rays, Tm: counting time (s), Qi : beam current (Coulomb) for irradiation time interval Dt (s) [using Multi Channel Scaler : MCS] N : number of produced atoms in the target (atom), A : dps/( A·h) I : beam current ( A) T : irradiation total time (h)

Rdionuclide production (2) 4) Cross-section Energy determination & attenuation correction 1. 2. Energy of Rdionuclide production (2) 4) Cross-section Energy determination & attenuation correction 1. 2. Energy of each stack sample -TRIM code 1. 2. Attenuation of sample - Shen’s empirical formula

3. Results & Discussion 1. Neutron spectrum; 0~110 -deg. ・Li, Be Ed= 25 Me. 3. Results & Discussion 1. Neutron spectrum; 0~110 -deg. ・Li, Be Ed= 25 Me. V  thick, thin (Li) Ed= 40 Me. V thick, thin (Li) ・C, Al, Fe, Cu, Ta, W Ed= 40 Me. V  thick 2. Radionuclide production Target: Li, C, Al, Fe, Ta, W Nuclides; 7 Be, 22 Na, 24 Na,

nat. Li(d, xn) Ed = 25 Me. V Thick lithium nat. Li(d, xn) 0 -deg nat. Li(d, xn) Ed = 25 Me. V Thick lithium nat. Li(d, xn) 0 -deg for 25 Me. V Comparison with Lone’s data

nat. Li(d, xn) Ed = 40 Me. V Thick and thin lithium thick nat. Li(d, nat. Li(d, xn) Ed = 40 Me. V Thick and thin lithium thick nat. Li(d, xn) for Ed= 40 Me. V  [7 Li(d, n) Qvalue=+15. 0 Me. V] thin nat. Li(d, xn) for Ed= 40 Me. V  [7 Li(d, n) Qvalue=+15. 0 Me. V]

  nat. Li(d, xn)  [7 Li(d, n) Q値=+15. 0 Me. V] nat. Be(d, xn)   nat. Li(d, xn)  [7 Li(d, n) Q値=+15. 0 Me. V] nat. Be(d, xn) [9 Be(d, n) Q値=4. 36 Me. V]

Li; comparison with exp. & calculation Li; comparison with exp. & calculation

Neutron yields 4π-integrated 0゜- differential Neutron yields 4π-integrated 0゜- differential

D 25 Me. V thin spectra: Serber / Advanced Serber model * * H. D 25 Me. V thin spectra: Serber / Advanced Serber model * * H. Utsunomiya (MSU); Phys. Rev. , C 32 (1985) 32

D 40 Me. V thin spectra: Serber / Advanced Serber model D 40 Me. V thin spectra: Serber / Advanced Serber model

nat. C(d, xn),27 Al(d, n) C spectra Al nat. C(d, xn),27 Al(d, n) C spectra Al

Fe, Ta(d, n) Fe, Ta(d, n)

Fe, Ta(d, n): comparison J. P. Meulders, et al. , Phys. Med. Biol. , Fe, Ta(d, n): comparison J. P. Meulders, et al. , Phys. Med. Biol. , 20, (1975) 235 -243 K. Shin, et al. , Phys. Rev. C, 29, (1984) 1307 -1316

Cross-section systematics vs mass (d, n) @Ed=40 Me. V Li(d, n) : largest yields Cross-section systematics vs mass (d, n) @Ed=40 Me. V Li(d, n) : largest yields C(d, n) : yield is larger than heavy element M. Hagiwara, et al. , J. Nucl. Materials, 329 -333, (2004) 218 -222 M. Hagiwara, et al. , J. Fusion Sci. Tech. , in print

Spectrum mass-dependence M. Hagiwara, et al. , J. Nucl. Materials, 329 -333, (2004) 218 Spectrum mass-dependence M. Hagiwara, et al. , J. Nucl. Materials, 329 -333, (2004) 218 -2 M. Hagiwara, et al. , J. Fusion Sci. Tech. , in print ・Spectrum becomes softer with mass

Comparison with MCNPX; Fe, Ta Comparison with MCNPX; Fe, Ta

Radionuclide production nat. Li(d, x)7 Be activation cross-section ,nat. Li(d, x)7 Be activity (TTY) Radionuclide production nat. Li(d, x)7 Be activation cross-section ,nat. Li(d, x)7 Be activity (TTY) lithium (IFMIF target) Ed= 40, 38. 6, 29. 7, 28. 2, 19. 7, 17. 7, 10, 7. 05 Me. V nat. Li(d, x)7 Be activation cross-section nat. Li(d, x)7 Be activity (TTY)

nat. C(d, x)7 Be ・PHITS code (JQMD and GEM) 27 Al(d, x)7 Be  ・PHITScode nat. C(d, x)7 Be ・PHITS code (JQMD and GEM) 27 Al(d, x)7 Be  ・PHITScode ・other exps.

27 Al(d, x)24 Na ・PHITS code ・Other Exps. ・Recommendation 27 Al(d, x)22 Na ・PHITS 27 Al(d, x)24 Na ・PHITS code ・Other Exps. ・Recommendation 27 Al(d, x)22 Na ・PHITS code ・Other Exps. ・Recommendation

Estimation 27 Al(d, x)24 Na activity (TTY) nat. C(d, x)7 Be activity (TTY) ・compare Estimation 27 Al(d, x)24 Na activity (TTY) nat. C(d, x)7 Be activity (TTY) ・compare with IAEA 27 Al(d, x)22 Na 27 Al(d, x)7 Be activity (TTY) ・compare with IAEA data

Fe Activation cross-section (I) nat. Fe(d, x)51 Cr nat. Fe(d, x)52 Mn *TALYS is a Fe Activation cross-section (I) nat. Fe(d, x)51 Cr nat. Fe(d, x)52 Mn *TALYS is a nuclear reaction program using update code parameter created at NRG Petten.

Fe Activation cross-section (II)  nat. Fe(d, x)57 Co nat. Fe(d, x)56 Co nat. Fe(d, x)58 Fe Activation cross-section (II)  nat. Fe(d, x)57 Co nat. Fe(d, x)56 Co nat. Fe(d, x)58 Co

Summary & Future 1. Measurements of neutron spectrum for (d, nx) reactions 1) Li,Be, Summary & Future 1. Measurements of neutron spectrum for (d, nx) reactions 1) Li,Be, C,Al,Fe,Cu,Ta   - Ed=40, 25 Me. V, - 0~ 110 deg - Energy spectrum shape was clarified, high energy tail 2) Systematics vs target mass 2. Production yields of radio-nuclides via (d, x) reaction 1) Li,C,Al,Fe,Cu,Ta Provided data base for IFMIF optimization & post irradiation analysis Future program: Deuteron induced reactions & neutron induced reactions * CDCC (Continuum-discritized coupled-channel) model; BRC * Extended Serber model ?

CYRIC new neutron course (@TR 3 extension) 3~100 A p beam 7 Li(p, n) CYRIC new neutron course (@TR 3 extension) 3~100 A p beam 7 Li(p, n) beam dump 74 cm Ep = 50 Me. V, E = 2 Me. V mono-E n flux 106 n/cm 2 s A • Software error rate • n-induced activation, reaction few-body reactions, etc.

Reference n n n n n [1] IFMIF CDA TEAM, IFMIF Conceptual Design Activity Reference n n n n n [1] IFMIF CDA TEAM, IFMIF Conceptual Design Activity Final Report edited by Marcello Martone, Report 96. 11, Enea, Dipartimento Energia, Frascati (1996) [2] M. A. Lone et al. , Nucl. Instrum. Methods, 143 (1977) 331 [3] M. Baba, T. Aoki, M. Hagiwara et al. , J. Nucl. Materials 307 -311 (2002) 1715 -1718. [4] T. Aoki, M. Hagiwara, M. Baba et al. , J. Nucl. Sci. and Tech. to be published [5] A. Terakawa et al. , Nucl. Instrum. Methods A 491 (2002) 419. [6] M. Baba, H. Wakabayashi, M. Ishikawa, T. Ito and N. Hirakawa, J. Nucl. Sci. Technol. , 27(No. 7), 601 (1990) [7] T. Aoki , M. Baba, S. Yonai, N. Kawata, M. Hagiwara, T. Miura, T. Nakamura, Nucl. Sci. Eng. , in print [8] J. F. Ziegler, J. P, Biersack, U. Littmark, Pergamon Press, New York (1984). [9] S. Meigo Nucl. Instrum. Methods in Physics Research A 401 (1997) 365 [10] M. B. Chadwick, P. G. Young et al. , Nucl. Sci. Eng. 131, 293, 1999 [11] W. Nelson, H. Hirayama, D. W. O. Rogers, “The EGS 4 Code System” SLAC-265, Stanford University, Stanford (1985) [12] W. Q. Shen, B. Wang, J. Feng, W. L. Zhan, Y. T. Zhu and E. P. Feng, Nucl. Phys. A, 491, 130 (1989) [13] J. P. Meulders et al. Phys. Med. Biol. , 20, p. 235, 1975 [14] Z. Radivojevic, A. Honkanen, J. Aysto, V. Lyapin, V. Rubchenya, W. H. Trzaska, D. Vakhtin and G. Walter, Nucl. Instr. and Meth. B. , 183, p. 212, 2001 [15] S. P. Simakov, U. Fisher, U. von Mllendorf, I. Schmuck, A. Yu. Konobeev, Yu. A. Korvin, P. Pereslavtsev; J. Nucl. Materials, 307 -311 1710 -1714 (2002) [16] S. Takacs, F. Szelecsenyi, F. Tarkanyi, M. Sonck, A. Hermanne, Yu. Shubin, A. Dityuk, M. G. Mustafa, Z. Youxiang, Nucl. Instr. and Meth. B. , 174 (2001) 235 -258 [17] U. Martens and G. W. Schweimer, Zeitschrift für Physics 233 (1970) 170 [18] IAEA, Charged-particle cross section database for medical radioisotope production http: //www-nds. iaea. org/medical/ [19] H. Iwase, K. Niita, T. Nakamura, J. Nucl. Sci. Tech. 39, No. 11, 1142 (2002)

Differential TTY of Ep=50 Me. V         nat. C: 12 C(p, n), 13 C(p, Differential TTY of Ep=50 Me. V         nat. C: 12 C(p, n), 13 C(p, n) Ep=70 Me. V  

3. Differential TTY (Thick target neutron yield)  ・Scarcity of experimental data for whole spectrum 3. Differential TTY (Thick target neutron yield)  ・Scarcity of experimental data for whole spectrum       “Measurement of full energy range ” ・Target: 30 -mm-diam x full stop thickness   0 -110 deg. , ・Efficiency; SCINFUL-R Correction; Attenuation in target, air ・Comparison with LA-150

TTY: W(p, n) Ep=50 Me. V Ep=70 Me. V TTY: W(p, n) Ep=50 Me. V Ep=70 Me. V

Neutron-induced activation X-section Neutron-induced activation X-section

1. はじめに (4) 目 的 1. IFMIF加速器構成材核種の(d, n)中性子スペクトルの測定   ・Li, C, Al, (Fe, Cu) ・Ed=25 - 1. はじめに (4) 目 的 1. IFMIF加速器構成材核種の(d, n)中性子スペクトルの測定   ・Li, C, Al, (Fe, Cu) ・Ed=25 - 40 Me. V, 0 – 90゜ ・厚いターゲット,薄いターゲット   ・スペクトルの全範囲の測定 2. IFMIF加速器構成材核種と重陽子反応による放射性核種生成   ・Li, C, Al, (Fe, Cu)   ・厚いターゲット,薄いターゲット ・スタックターゲット法による励起関数の導出   ・ 7 Be, (3 H), , 24 Na  

3. 実験 1.東北大学サイクロトロン   ・第五ターゲット室,   ・ビームチョッパー   ・ビームスウィンガー+飛行管室;      高いエネルギー分解能, S/N比,広いスペクトル範囲 2. スタックターゲットの利用   ・厚いターゲットと薄いターゲットの対する同時測定   ・中性子スペクトル,放射化の同時測定 3. 実験 1.東北大学サイクロトロン   ・第五ターゲット室,   ・ビームチョッパー   ・ビームスウィンガー+飛行管室;      高いエネルギー分解能, S/N比,広いスペクトル範囲 2. スタックターゲットの利用   ・厚いターゲットと薄いターゲットの対する同時測定   ・中性子スペクトル,放射化の同時測定

INTRODUCTION(2)  n+28 Si (LA 150) INTRODUCTION(2)  n+28 Si (LA 150)