Measurement of Fe58(p,n)Co58 reaction cross-section within the proton energy range of 3.38 to 19.63 MeV

Measurement of Fe58(p,n)Co58 reaction cross-section within the proton energy range of 3.38 to 19.63 MeV

Accepted Manuscript Measurement of 58 Fe(p, n)58 Co reaction cross-section within the proton energy range of 3.38 to 19.63 MeV Reetuparna Ghosh, Sylv...

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Accepted Manuscript Measurement of 58 Fe(p, n)58 Co reaction cross-section within the proton energy range of 3.38 to 19.63 MeV

Reetuparna Ghosh, Sylvia Badwar, Bioletty Lawriniang, Betylda Jyrwa, Haldhara Naik et al.

PII: DOI: Reference:

S0375-9474(17)30101-X http://dx.doi.org/10.1016/j.nuclphysa.2017.04.030 NUPHA 20882

To appear in:

Nuclear Physics A

Received date: Revised date: Accepted date:

27 January 2017 24 April 2017 25 April 2017

Please cite this article in press as: R. Ghosh et al., Measurement of 58 Fe(p, n)58 Co reaction cross-section within the proton energy range of 3.38 to 19.63 MeV, Nucl. Phys. A (2017), http://dx.doi.org/10.1016/j.nuclphysa.2017.04.030

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Highlights • The excitation function of 58 Fe(p,n)58 Co reaction is important from the point of proton accelerator. • 58Co is necessary for labelling in Cyanocobalamin (vitamin B-12) and hydroxycobalamin diagnostic purpose. • The excitation function of 58 Fe(p,n)58 Co reaction is important to test nucler model such as TALYS.

Measurement of 58Fe(p, n)58Co reaction cross-section within the proton energy range of 3.38 to 19.63 MeV Reetuparna Ghosha, Sylvia Badwara, Bioletty Lawrinianga, Betylda Jyrwaa, Haldhara Naikb*, Yeshwant Naikc, Saraswatula Venkata Suryanarayanad, Srinivasan Ganesane a

Physics Department, North Eastern Hill University, Meghalaya-79302, India

b

Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai-400085, India

c

Product Development Division, Bhabha Atomic Research Centre, Mumbai 400085, India

d e

Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India

Raja Ramana Fellow of HBNI, Bhabha Atomic Research Centre, Mumbai 400085, India

*

Communicating author email: [email protected]

Abstract The

58

Fe(p, n)58Co reaction cross-section within Giant Dipole Resonance (GDR) region

i.e. from 3.38 to 19.63 MeV was measured by stacked-foil activation and off-line Ȗ-ray spectrometric technique using the BARC-TIFR Pelletron facility at Mumbai. The present data were compared with the existing literature data and found to be in good agreement. The 58

Fe(p, n)58Co reaction cross-section as a function of proton energy was also theoretically

calculated by using the computer code TALYS-1.8 and found to be in good agreement, which shows the validity of the TALYS-1.8 program. Keywords:

58

Fe(p, n)58Co reaction, cross-section, activation, Ȗ-ray spectrometric technique,

TALYS-1.8 1. Introduction Production of proton induced reaction cross-section of iron is important from accelerator point of view and many other applications. In reactors, stainless steel is a primary constituent, which is used as the calandria vessel and pipe lines of secondary coolant circuit. In accelerator driven sub-critical system (ADSs), the high energy proton beam has to be accelerated through a metallic tube made up of stainless steel. Hence, iron is often found in the beam line component. Stainless steel is also one of the major components in low and high energy accelerators [1]. Iron has four stable isotopes (54Fe~5.85%,

56

Fe~ 91.75%,

57

Fe ~

2.12%, and 58Fe~ 0.28%) and is an essential structural material [2]. Thus, it is very important to know about the proton, deuteron, alpha particles and heavy ion induced reaction crosssections from from

nat

nat

Fe at various energies. In particular proton-induced reaction cross-sections

Fe are important for the production of medical isotopes and nuclear transmutation in

astrophysics. For example,

56,57

Co produced from

nat

Fe(p, xn) reaction is used as the

calibration source of the Ȗ-ray detector at energy above 1 MeV. The radioisotope 55Co is used in positron emission tomography (PET) [3]. On the other hand, the radioisotope 57Co is used as a new positron-emitter to label bleomycin (an anti-cancer chemotharapy drug) [11]. This is used for the single photon emission computerized tomography (SPECT) [4]. The radioisotopes 57Co or 58Co are used in the diagnosis of pernicious anaemia, which is fatal to human life. The pernicious anaemia is caused by vitamin B-12 deficiency due to its poor absorption in small intestine. Cyanocobalamin (vitamin B-12) and hydroxycobalamin labelled with 57Co or 58Co are commercially available for diagnostic use. The radionuclide 55Co can be produced from the 56Fe(p, 2n) reaction. On the other hand, 57

Co can be produced from the

57

Fe(p, n) reaction, which needs enriched 57Fe target. In the

nat

Fe(p, x) reaction, 58Co is also produced along with the

55,57

Fe. Thus, for the production of

selective reaction products, either enriched Fe target or selection of proper proton beam energy is very much necessary. This means that the studies on the proton-induced reaction cross-sections of

nat

Fe from threshold value to an optimum energy are very much necessary.

Besides this, the proton induced reaction cross-sections from

nat

Fe are of considerable

significance for testing of nuclear model and various other applications. In EXFOR [6] compilation, the proton-induced reaction cross-sections from

nat

Fe are

available based on the work of various authors [7-28]. From these works, it can be seen that the detailed cross-sections for the

nat

Fe(p, x)55,57Co reactions are available, whereas for the

nat

Fe(p, x)58Co reaction, it is very much limited [18-23]. In the present work, the

nat

Fe(p,

x)58Co reaction cross-section within the proton energy range of 3.38 to 19.63 MeV has been measured by using a stacked-foil activation and an off-line Ȗ-ray spectrometric technique. The

nat

Fe(p, x)58Co reaction cross-section at different proton energy was also calculated by

using the computer code TALYS 1.8 [29]. The cross-sections from the present work are found to be in good agreement with the literature data [18-23] and the values from the TALYS-1.8 [29] calculation. 2. Experimental Details and Data analysis

The

nat

Fe(p, x)58Co reaction cross-section was measured by stack foil irradiation

technique at 14 UD BARC-TIFR Pelletron facility at TIFR, Mumbai, India [30]. The conventional stack-foil technique was used in the experiment as done by most of the authors [1, 7–28]. Natural iron foils of 99.99% purity, 100 ȝm thickness and 0.7x0.7 cm2 size were used as targets. Natural copper foils of 99.99% purity, 108 ȝm thickness and 0.8x0.8 cm2 size were used as energy degrader and monitor. A stack of Al foil and five identical pairs (Fe-Cu) of metal foils was made. The stack-foil was made by keeping the Fe and Cu foils alternately. Five Fe, five Cu, and one Al foil were used in the stack. The Al foil of 99.99% purity used in the first position of the stack was of 108 ȝm thickness and 0.8x0.8 cm2 size. The stack was additionally wrapped with 0.025 mm thick Al foil and then mounted at zero degree with respect to the beam direction. The stack was irradiated for 30 minutes with a proton-beam of 21 MeV. The proton beam at 6 m height above the analysing magnet of the Pelletron was used to utilize the maximum proton current from the accelerator. The beam current was 28 nA and was kept constant during the irradiation. A collimator of 6 mm diameter for the proton beam was used during the experiment. Thus it was ensured that equal areas of the monitor and the target foils intercepted the beam. The irradiated samples were cooled for 0.083-180.33 h and then taken for off-line Ȗ-ray spectrometry. The irradiated samples were mounted on different Perspex plates. The measurements of Ȗ-ray activities of the irradiated samples were started from the lowest proton energy side after cooling time of 2 h. Then Ȗ-ray counting of Cu monitor and Fe samples were performed in succession for 0.08-1.25 h by using energy and efficiency calibrated HPGe detector coupled to PC based 4k channel analyser. A

152

Eu standard source was used for the energy and efficiency calibration. The

resolution (full width at half maximum (FWHM)) of the detector system during counting was 2.0 keV at 1332 keV of 60Co. The source-to-detector distance was kept long enough to ensure a point-like geometry and a dead time lower than 10 % to avoid pileup effect. Each sample was measured twice with increasing counting time to avoid disturbance by overlapping Ȗlines from undesired sources. An initial proton beam of 21 MeV hits the 108 ȝm thick Al foil before hitting the target. Thus, the incident proton-beam was 19.63 MeV on the first target foil based on SRIM-2013 [31] calculation. The proton beam intensity was determined by using the

nat

Cu(p, x)62Zn

monitor reaction cross-section [34] based on the Ȗ-ray activity of 62Zn formed on the monitor foil at the first position of the stack. The proton beam intensity was considered as constant to determine the cross-section of 58Fe(p, n)58Co reaction for each foil in the stack, as the loss of

proton beam flux is very small and very hard to deduce practically [1]. The degradation of the proton beam along the stack was calculated by using the computer code SRIM-2013 [31]. The activation cross-section (ı) for the

58

Fe(p, n)58Co reaction at the i-th sample was

calculated using the conventional activation formula [1].

ı(i) =

ఒெ஺೚್ೞ

ɂ൫ாം ൯ூം ேఘఝ൫ଵି௘ షഊ೟೔ ൯௘ షഊ೟೎ ሺଵି௘ షഊ಴ಽ ሻ

(1)

where Ȝ is the decay constant (Ȝ= ln2/T1/2) of the reaction product of interest with half-life T1/2. M is the atomic weight, t is the target thickness and ij is the proton beam intensity i.e. the number of protons per unit time. Aobs is the net counts under the photo-peak area at the ith sample, İ(EȖ) is the efficiency of the detector and IȖ is the branching intensity or abundance of the 810.76 keV Ȗ-line of 58Co. N is the Avogadro’s number, ȡ is the density of the target (7.874 gm/cm3). ti, tc and CL are the irradiation time, cooling time and counting time, respectively. The nuclear spectroscopic data used in the above calculations are taken from the Ref. [32] and shown in Table 1. The threshold energies were calculated on the basis of Q-tool system [33]. The standard cross-section of the beam monitor was taken from a chargedparticle cross-section database for medical radioisotope production [34]. 3. Result and Discussion The

58

Fe(p,n)58Co reaction cross-section values determined within the proton energy

range of 3.38 to 19.63 MeV are shown in Table 2. The uncertainties associated with the experimental reaction cross-sections are based on the replicate measurements. The overall uncertainty is the quadratic sum of statistical and systematic uncertainties. The statistical uncertainty in the observed activity is primarily due to counting statistics, which is estimated to be 2.2%–7.4%. This can be determined by accumulating the data for an optimum time period that depends on the half-life of nuclide of interest. The systematic uncertainties are due to uncertainties in proton flux estimation (2.5%), the irradiation time (‫׽‬0.5%), the detection efficiency calibration (‫׽‬3%), the half-life of the reaction products and the ߛ-ray abundances (‫ ׽‬2%) as reported in the literature [32]. Thus the total systematic uncertainty is about ‫׽‬4.4%. The overall uncertainty is found to range between 4.9% and 8.6%, coming from the combination of statistical uncertainty of 2.2%–7.4% and systematic uncertainty of 4.4%.

The measured cross-sections at the proton energies of 19.63, 16.66, 13.27, 9.16 and 3.38 MeV are reported for the first time (Table 2). The experimental data from the present work and the literature data from Refs. [18-23] are plotted in Fig. 1 for comparison. It can be seen from Fig. 1 that the present data at the proton energies of 19.63, 16.66, 13.27 and 9.16 MeV are in good agreement with the literature data [18-21]. However, the present datum at the proton energy of 3.38 MeV is significantly higher than the similar data of S.Tims et al. [22]. In order to examine this, the

58

Fe(p,n)58Co reaction cross-section from the threshold to 45

MeV was taken from TENDL data library [35] and plotted in Fig. 1. It can be seen from Fig. 1 that the data from the present work and literature [18-22] for the proton energy below 10 MeV are in close agreement with the values from TENDL data library [35]. However, the data for the proton energy above 10 MeV are slightly on the higher side than the values of TENDL data library [35]. This may be because the

58

Fe(p, n)58Co reaction cross-section

tabulated in the TENDL data library [35] based on TALYS calculation is due to the use of default parameters. In view of this the

58

Fe(p, n)58Co reaction cross-section from the

threshold to 30 MeV was calculated by using the computer code TALYS 1.8 [29] with default and adjusted parameters. TALYS [29] can be used to calculate the reaction cross-section based on physics models and parameterizations. It calculates nuclear reactions involving targets with mass larger than 12 atomic mass units and projectiles like photon, neutron, proton, 2H, 3H, 3He and alpha particles in the energy range from 1 keV to 200 MeV. In the present work, we have calculated the 58Fe(p, n)58Co reaction cross-section from the threshold energy to 30 MeV by using the default and adjusted parameters. All possible outgoing channels in the proton induced reactions of 58Fe were considered. However, the 58Fe(p, n)58Co reaction cross-section was collected and plotted in the Fig. 1. It can be seen from Fig. 1 that the values from TALYS 1.8 based on the default parameters agree very well with the values from TENDL data library [35]. In the present work, the level density parameters were adjusted accordingly to get a better agreement with the experimental values and literature data [18-22]. Level density is an important characteristic of the nucleus, as it permits one to acquire information about the structure of the excited nuclei and analyze the process of nuclear excitations. In the present calculation, the energy dependence of the level-density parameter plays a very important role. This is due to the fact that the typical spacing of the first excited nuclear levels in medium and heavy nuclei is of the order of a tenth or some tenths of MeV for low excitation energies. As the excitation energies increase, the typical spacing of the nuclear levels decreases and thus the typical density of levels increases. So a quick individual

explanation is no longer viable [36]. The level-density parameter Ȝ varies with energy according to the equation:

Ȝ= Ȝ෨ ሺͳ ൅ ߜߝ଴

ሺଵି௘ షംೆ ሻ ௎

)

(2)

where ߣሚis the asymptotic value of Ȝ at high excitation energy. įİ0 is the shell correction of the nuclear binding energy, whose magnitude establishes how Ȝ is different from ߣሚ at low energies. The sign of the shell correction term įİ0 regulates whether Ȝ(U) increases or decreases as a function of U, which is the effective excitation energy. Ȗ is the damping parameter, which governs how fast Ȝ approaches ߣሚ . The level-density parameter Ȝ shows the presence of shell effects at low energy and their disappearance at high energy in a phenomenological manner. The asymptotic value of ߣሚ is given by ߣሚ ൌ ߙ‫ ܣ‬൅ ߚ‫ܣ‬ଶȀଷ

(3)

where A is the mass number, ߙƒ†ߚare global parameters that have been determined to give the best average level density description over a whole range of nuclides [29]. Table 3 shows the values of default and adjusted parameters of TALYS 1.8 calculation used in the present work. The 58Fe(p, n)58Co reaction cross-section values obtained from the TALYS 1.8 based on adjusted parameters above the proton energy of 10 MeV are in agreement with the experimental data of present work and literature [18-22]. However, below the proton energy of 10 MeV, the values from the TALYS 1.8 based on adjusted parameters are higher than the experimental data of present work and literature data [18-22]. Thus the experimental 58Fe(p, n)58Co reaction cross-section gives a very good test of the theoretical model and idea of production of the medical isotope. 4. Conclusion The

58

Fe(p, n)58Co reaction cross-section within proton energy range of 3.38 to 19.63

MeV was measured by stacked-foil activation and off-line Ȗ-ray spectrometric technique. The present data were compared with the existing data from literature and TENDL data library. The 58Fe(p, n)58Co reaction cross-section as a function of proton energy was also theoretically calculated by using the computer code TALYS-1.8 with default and adjusted parameters. The

experimental data from the present work, literature and TENDL data library below the proton energy of 10 MeV are in good agreement with the values from TALYS based on default parameters. However, experimental data from the present work, literature and TENDL data library above the proton energy of 10 MeV are in good agreement with the values from TALYS based on adjusted parameters. Acknowledgement One of the authors (R. Ghosh) thanks BRNS for giving her the project for Ph.D. work. She also thanks the staff of Pelletron facility, TIFR, Mumbai for their excellent operation of the accelerator and giving the proton beam during the irradiation. References [1] K. Kim, M.U. Kandaker , H. Naik, G. Kim, Nucl.Instr.Metd.B 322 (2014) 63. [2] A. Negret, C.Borcea, Ph. Dessagne, M. Kaeveno, A. Olacel, A.J.M Plompen, M. Stanoiu, Phys.Rev.C 90 (2014) 034602. [3] P. Goethals, A. Volkaert, C. Vandewielle, R. Dierckx, N. Lameire, Nucl. Med. Biol. 27 (2000) 77. [4] E. Daum, S.M. Qaim, Progress Report on Nuclear Data Research in the Federal Republic of Germany, NEA/NSC/DOC-13, INDC -043 (1997) 4–8. [5] http://ntips4u.blogspot.in/2009/01/diagnostic-and-therapeutic-uses-of.html [6] N. Otuka, D.L. Smith, Nuclear Data Sheets 120 (2014) 281- (IAEA-EXFOR Database, http://www-nds.iaea.org/exfor). [7] I.R. Williams, C.B. Fulmer, Phys. Rev. 162 (1967) 1055. [8] I.L. Jenkins, A.G. Wain, J. Inorg. Nucl. Chem. 32 (1970) 1419. [9] R.L. Brodzinski, L.A. Rancitelli, J.A. Cooper, N.A. Wogman, Phys. Rev. C 4 (1971) 1257. [10] J.N. Barrandon, J.L. Debrun, A. Kohn, R.H. Spear, Nucl. Instr. Meth. 127 (1975) 269. [11] M.C. Lagunas-Solar, J.A. Jungerman, J. Appl. Radiat. Isot. 30 (1979) 25. [12] N.C. Schoen, G. Orlov, R.J. McDonald, Phys. Rev. C 20 (1979) 88. [13] R. Michel, G. Brinkmann, H. Weigel, W. Herr, Nucl. Phys. A 322 (1979) 40 [14] R. Michel, G. Brinkmann, J. Radioanal. Chem. 59 (1980) 467. [15] A.E. Antropov, P.P. Zarubin, Y.A. Aleksandrov, I.Y.U, Gorshkov, Conf. Nucl. Spectr. and Nucl. Struct., Leningrad (1985) 369. [16] I.F. Barchuk, V.S. Bulkin, V.A. Kuzmenkova, P.M. Kurilo, Y.N. Lobach,

A.F. Ogorodnik, V.S. Procopenko, V.V. Tokarevsky, Atomnaya Energiya 63 (1987) 30. [17] P. Jung, J. Nucl. Mater. 144 (1987) 43. [18] P.P. Zarubin, N.N. Abu Issa, A.V. Smirnov, A.E. Antropov, in: 39 Conf. Nucl. Spectrosc. and Nucl. Struct., Tashkent 1989, (1989) p. 281, USSR. [19] P.P. Zarubin, N.N. Aby Issa, A.V. Smirnov, A.E. Antropov, Izv. Rossiiskoi Akademii Nauk, Ser.Fiz. 54 (1990) 104. [20] V.N. Levkovski, Book: Levkovskij,Act.Cs. By Protons and Alphas, Moscow 1991, (1991), USSR. [21] Z. Wenrong, Y. Hanlin, Y. Weixiang, Chinese J. Nucl. Phys. 15 (1993) 337. [22] S.G. Tims, A.F. Scott, A.J. Morton, V.Y. Hansper, D.G. Sargood, Nucl. Phys. Sect. A 563 (1993) 473. [23] S. Takacs, L. Vasvary, F. Tarkanyi, Nucl. Instr. Meth. B 89 (1994) 88. [24] S. Sudar, S.M. Qaim, Phys. Rev. 50 (1994) 2408. [25] R. Michel, G. Brinkmann, H. Busemann, R. Daunke, M.M. Gloris, H.J. Lange, B. Klug, A. Krins, I. Leya, M. Lupke, S. Neumann, H. Reinhardt, M. Schnatz-Buttgen, U. Herpers, T. Schiekel, F. Sudbrock, B. Holmqvist, H. Conde, P. Malmboug, M. Suter, B. Dittrich-Hannen, P.W. Kubik, H.A. Synal, D. Filges, Nucl. Instr. Meth. B 129 (1997) 153. [26] S.S. Ratkevich, I.D. Fedorets, B.A. Nemashkalo, V.E. Storizhko, Phys. At. Nucl. 63 (2000) 1497. [27] B.A. Nemashkalo, I.D. Fedorets, S.S. Ratkevich, V.E. Storizhko, Yad. Fiz. 11 (2000) 13. [28] A. Al-Abyad, M.N.H. Comsan, S.M. Qaim, Appl. Radiat. Isot. 67 (2009) 122. [29] A.J. Koning, S. Hilaire, S. Goriely, TALYS user manual a nuclear reaction program, User manual. NRG-1755 ZG PETTEN, The Netherlands (2015). [30] H. Naik, G.N. Kim, S.V. Suryanarayana, K.S. Kim, M.W. Lee, G. Sanjeev, V.T. Nimje, K.C. Mittal, A. Goswami, S. Ganesan, Jour. Nucl. Phys. Mat. Sc..Rad. Appl. 3 (2015) 55. [31] J.F. Ziegler, Nucl.Instr.Metd.B (2004) 219. [32] NuDat 2.6 (2011) National Nuclear Data Center Brookhaven National Laboratory, http://www.nndc.bnl.gov/ [33] Qtool: calculation of Reaction Q-values and threshold, Los Alamos national Library, http://cdfe.sinp.msu.ru/services/calc_thr/calc_thr.html [34] IAEA-TECDOC-1211, https://www-nds.iaea.org/medical/monitor_reactions.html (2011) [35] A.J. Koning, D. Rochman, S.C. van der Marck, J. Kopecky, J. Ch. Sublet, S. Pomp, H.

Sjostrand, R. Forrest, E. Bauge, H. Henriksson, O. Cabellos, S. Goriely, J. Leppanen, H. Leeb, A. Plompen, R. Mills, S. Hilaire, TENDL-2014: TALYS-based evaluated nuclear data library. Available from: . [36] D. Suchiang, J.J. Jeremiah, B. Jyrwa, Pramana. 83 (2014) 545.

Table and figure captions Table 1. Nuclear Spectroscopic data of the radio-nuclides from Ref. [32]

Reaction

Nuclides Spin

Half-life

state J ʌ 62

Cu(p,n)

63

Cu(p,2n)

58

Fe(p,n)

63

58

0+

Zn

2+

Co

Decay

Ȗ-ray energy Ȗ-ray intensity Eth (MeV)

mode (%) EȖ (keV) 9.186±0.13 h İ (100)

70.86±0.06 d İ (100)

IȖ (%)

507.60± 0.10 14.8±0.14

2.448

596.56± 0.13 26

13.568

810.76±0.02 99.45

3.1437

Table 2. The 58Fe(p, n)58Co reaction cross-section for the proton energy range of 3.38 to 19.63 MeV. Proton energy

ı (mb) [34]

ĭ (p-cm-2-h-1)

(MeV)

nat

x1014

18.21

Cu(p.x)63Zn

46.248

<ı> (mb) 58

7.23± 0.18

Fe(p,n)58Co

Present work

Talys 1.8

19.63

89.18±1.32

96.51

16.66

228.74±13.87

226.22

13.27

729.02±89.24

598.95

9.16

714.92±64.51

787.86

3.38

144.07±0.64

17.37

Table 3. Default and adjusted parameters used in the Talys 1.8 [29] calculation for constant temperature model (CTM). ld model parameter option value varies from 1 to 6. The default value = 1 refers to the CTM. Different parameters (MeV-1)

Default values for

Adjusted values for

CTM-effective

CTM-effective

ߙ

0.0692

0.034

ȕ

0.2827

0.2827

Ȗ

0.433

0.433



1.1 1.0

1991,V.N.Levkovskij 1993,S.G.Tims+ 1990,P.P.Zarubin+ PresentWork Talys1.8 Default Talys 1.8 A.E.Antrov+1985 P.P.Zarubin+1989 TENDL2015

0.9

Cross-section (barns)

0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 -0.1

0

5

10

15

20

25

30

35

40

45

Proton energy (MeV)

㻌 㻌 Fig. 1. Comparison of the present experimental 58Fe(p,n)58Co reaction cross-section with the literature and theoretical data.㻌