Ph D PhotonuclearData Evaluation at CNDC R.R. Xu 1, X. Tao 1, J. M. Wang 1, Y. Tian 1, X. B. Ke 1, B.S. Yu 1, H. C. Hai 2, J. S. Zhang 1, Z. G. Ge 1 1 China Nuclear Data Center China Institute of Atomic Energy 1 China Nuclear Data Center, China Institute of Atomic Energy 2 Nankai University
Content: 1. Motivation of PD evaluation at CNDC 2. Evaluation methods at CNDC 3. Some results 4. Summary 2
1. Motivation of PD evaluation at CNDC Photonuclear data (PD) are important in application to radiation damage, reactor dosimetry, accelerator shielding, radiation therapy and so on; and recently, the requirements e e of the high-quality data a for more oe nuclei are ae increasing from users; New measurements in high precision since 1999 are available to make it possibletoupdate p the previous recommended PD and evaluate data for more nuclei and reactions. The relevant evaluation techniques and codes at CNDC need to be improved; 28 nuclei are involved in this CRP at CNDC (nuclei in red are in this contract): 1) Update the data for 9 Be, 27 Al, 51 V, 50,52,53,54 Cr, 54,56,57,58 Fe, 63,65 Cu, 90,91,92,94,96 Zr, 180,182,183,184,186 W, 209 Bi; 2) New evaluations for 6,7 Li, 10,11 B. E 200MeV for middle-heavy nuclei; E 50MeV for 6,7 Li nuclei; E 30MeV for 9 Be, 10,11 B nuclei. 3
2. Evaluation methods at CNDC (Previous) Schematic flow of evaluation for PD in the previous CRP CRP No.8833 (1996-1999) Chief Participants: J. S. Zhang, B. S. Yu, Y. L. Han CEPDF (up to 30MeV): 9 Be, 27 Al, 51 V, 50,52,53,54 Cr, 54,56,57,58,, Fe, 63,65 Cu, 90,91,92,94,96 Zr, 180,182,183,184,186 W, 209 Bi Codes: GLUNF( 9 Be), GUNF(middle-heavy nuclei) Reactions: (,1n), (,1p), (,1 ), (,1 3 He), (,1d), (,1t), (,2n), (,np), (,n ), (,2p), (,3n) 4
2. Evaluation methods at CNDC (Previous) ENDF file of PD in the CRP-CNDC library (1996-1999) (1) Evaluations are completely l obtained based on the experimental data for 9 Be, 27 Al, 63,65 Cu, 51 V, 182,184,186 W, 209 Bi for MF=3: (,abs), (,2n), (,3n) ; (2) The theoretical codes GUNF, GLUNF( 9 Be) are used for the reactions and nucleus scarce of experimental data. 5
2. Evaluation methods at CNDC (current) Schematic flow of evaluation for PD in the current CRP GMEND GLUNF ( 6,7 Li, 10,11 B) CRP No.20466 (2016-2019) Chief Participants: RXu R.Xu,X. X Tao, J. Wang, Y. Tian, X. Ke, B. Yu, H. Hai, J. Zhang, Z. Ge New evaluation: 6,7 Li, 10,11 B, 9 Be, 27 Al, 51 V, 50,52,53,54 Cr, 54,56,57,58 56 57 58 Fe, 63,65 65 Cu, 90,91,92,94,9691 92 94 96 Zr, 180,182,183,184,186 W, 209 Bi Codes: GLUNF( 6,7 Li, 9 Be, 10,11 B), GMEND(middle-heavy nuclei) Reactions: (,1n), (,1p), (,1 ), (,1 3 He), (,1d), (,1t), (,2n), (,np), (,n ), (,2p), (,3n) 6
Scheme of GLUNF 1 Giant dipole resonance parameters were obtained by fitting exps. of (, abs) cross sections; 2 OMPs of neutron were obtained by fitting (, 1n) cross sections; If exps. of photonuclear data are absent, OMPs of neutron were searched automatically from n-a reactions; 3 OMPs of p,,, 3 He, d, t were obtained from concerned references; 4 The unified treatment of pre-equilibrium and equilibrium emission and the pick-up p mechanism for cluster emission are included; 5 Cascade transitions from the unstable residual to the stable one is included in the GLUNF code; 6 Recoil effect in multi-stage emission processes are included for the light nuclei. 7
Scheme of GMEND 1. 7 models including the microscopic RQRPA, SLO, MLO et al. are utilized to estimate the photon strength function and derive the gamma absorption XS (Ref. Y. Tian s talk ) 2. Optical models for n,p,alpha,d,t,he-3 (KD potential for n, p) 3. Equilibrium emission model(gilbert-cameron-cook-ignatyuk, Su Zongdi modification) 4. Pre-equilibrium emission model (2p-2h state) 5. Quasi-deuteron dissociation model 6. The emission particles include n,p,alpha,d,t,he-3; First to eighteenth emission processes are considered, more than 570 million reaction channels are involved in GMEND below 200MeV; 7. Pion production XS is not involved yet due to its small contribution (e.g. + 155 Cs less than 1*10-5 b below 200MeV) 8
Evaluation for 6 Li by GLUNF 9
Currently, the upper projectile energy for + 6,7 Li reaction codes reaches 50MeV. The concerned open channels are listed as follows: + 6 Li= 6 Li* > 1. (, ), 3 Li 6 BIND= 0.000 Q= 0.000 MeV THRESH= 0.000 MeV 2. (,n), 3 Li 5 BIND= 5.666 Q= 5.666 MeV THRESH= 5.666 MeV 3. (,p), 2 He 5 BIND= 4.594 Q= 4.594 MeV THRESH= 4.594 MeV 4. (,d), 2 He 4 BIND= 1.475 Q= 1.475 MeV THRESH= 1.475 MeV 5. (,t), 2 He 3 BIND=15.796 Q= 15.796 MeV THRESH=15.796 MeV Among the residuals, 5 Li, 5 He are both very unstable elements, and they generally decay through the two-body breakup mechanism immediately. Therefore, the two channels are subsequently considered after the 1 st particle emission process in GLUNF: 3 Li 5 p+a Q = 1.966 MeV 2 He 5 n+a Q = 0.894 MeV 10
+ 6 Li RQRPA Cal. The preliminary calculated channels in the ENDF 6 file of + 6 Li with GLUNF. 11
Evaluation for 90 Zr by GMEND 12
Para. of EGLO: E,1 =16.69 MeV,1 =245.07 mb,1 =3.53 MeV E,2 =20.75 MeV,2 =41.61 mb,2 =6.59 MeV,2 13
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Evaluation for 52 Cr by GMEND 18
No data for 50, 53,54 54 Cr; Discrepancies of exps. are existed for 52 Cr since 1999. + 52 Cr 52 Cr(,x)n measured by B.I.Goryachev+ in 1969 (,abs) Evaluation by B.S.Ishkhanov+ in 2002 52 Cr(,x)n measured by S.N.Belyaev+ in 2001 19
+ 52 Cr 20
+ 52 Cr 21
+ 52 Cr 22
+ 52 Cr 23
Evaluation for 186 WbyGMEND 24
on(b) 0.6 0.5 0.4 Discrepancies of exps. are existed 3. Some results B.L.Berman1969(n+np) Berman1969(n+np) B.L.Berman1969(2n+2np) B.L.Berman1969(3n) B.L.Berman1969(xn) A.M.Goryachev1978(n+np+2n) G.M.Gurevich1981(abs) P.Mohr2004(n) ross secti 0.3 C + 186 W 0.2 01 0.1 0 5 10 15 20 25 30 En(MeV) 25
Cr ross sectio on(b) 0.5 0.4 3. Some results 186 b Exp. data by + 186 W abs 0.45 0.35 0.3 0.25 0.2 0.15 0.1 0.05 Berman in 1969 are considered a little bit smaller. Black: JENDL-PD2004 Yellow: TENDL-2014 Blue: current result Para. of SLO: E,1 =12.50 MeV,1 =194.39 mb,1 =2.07 MeV E,22 =14.79 MeV,2 =380.67 mb,2 =5.51 MeV 0 5 10 15 20 25 30 En(MeV) 26
186 + 186 W 2n Cr ross sectio on(b) 0.25 0.2 0.15 0.1 purple: p current result green: TENDL-2014 005 0.05 0 10 15 20 25 30 En(MeV) 27
Summary In photonuclear data evaluation: More concentrations will be paid to the nuclei with new measurements, in particular to clarify the deviations among different evaluations and measurements; Besides the evaluated libraries, V. V. Varlamov and other authors evaluated the photonuclear reaction cross sections based on experimental data for most nuclei, which are very good references in our data evaluations; (,abs) XS is necessary input for the theoretical calculation. The method for reasonable estimation towards the nuclei without measurements are important; (, ) is not included in the entire evaluation system yet due to the small contribution, but the cross sections around the threshold of (,n) and (,abs) looks not reasonable, which is need to improve. 28
Participants of this CRP at CNDC Ruirui Xu PI Xi Tao Jingshang Zhang Jimin Wang Baosheng Yu Yuan Tian Zhigang Ge Xianbo Ke Chonghai Cai 29
Contact us gezg@ciae.ac.cn xuruirui@ciae.ac.cn i@ i jmwang@ciae.ac.cn tiany@ciae.ac.cn Thanksforyourattention! attention! 30
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