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MACS and Astrophysical Reaction Rates from ENDF/B-VII.0, JEFF-3.1, JENDL-3.3, ENDF/B-VI.8 Evaluated Neutron Libraries B. Pritychenko * , A. Sonzogni, S. Mughabghab National Nuclear Data Center Brookhaven National Laboratory * Email: [email protected]. Brookhaven Science Associates. - PowerPoint PPT Presentation
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Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
MACS and Astrophysical Reaction Rates from ENDF/B-VII.0, JEFF-3.1, JENDL-3.3, ENDF/B-VI.8 Evaluated
Neutron Libraries
B. Pritychenko*, A. Sonzogni,S. Mughabghab
National Nuclear Data CenterBrookhaven National Laboratory
*Email: [email protected]
Brookhaven Science Associates
2Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
Evaluated Neutron Libraries Nuclear Data activities started at BNL in
1951 with neutron compilations BNL-325 & Evaluated Nuclear Data File ENDF: core nuclear reaction database containing evaluated
(recommended) data from the ENDF/B-VII.0 library (also JEFF,
JENDL, BROND, CENDL and ENDF/B-VI.8). It uses ENDF-6
format, covering all nuclides of practical relevance (393 in total) for
neutrons from 10-5 eV up to 20 MeV
ENDF/B-VII.0 library was released on
December 15, 2006
3Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
ENDF/B-VII.0 Astrophysics Features
393 Neutron Evaluations in ENDF/B-VII.0 vs. 337
in JENDL-3.3 released in 2002 251 out of 286 nuclides (87.7%) from solar
nuclide abundances paper by E. Anders & N. Grevesse, Geochim. Cosmochin. Acta 53 (1989) 197
390 (n,) cross sections, no cross sections
for 3H, 4He, 7Be Good for Maxwellian-averaged cross sections
(s-process nuclei), astrophysical reaction rates
4Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
Project Motivation ENDF data in eV – MeV regions are
utilized by nuclear industry, fussion,
national security applications
keV region data for nuclear astrophysics Calculate 4 major neutron libraries
under the same conditions Connection between ENDF & astrophysics
Sigma: New ENDF Web interface
5Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
MACS & Reaction Rates I
Nuclear astrophysics s-process calculations require Maxwellian average neutron capture cross sections.
Maxwellian cross sectionin nuclear astrophysics region are not more than 10% off from (n,) cross sections
6Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
MACS & Reaction Rates II Nakagawa et al., ADNDT 91 (2005) 77 Maxwellian-averaged cross section, [b]
Astrophysical reaction rate, [cm3/s]
/2
)(2410)9(
kTTv
TvkTMaxwANTR
vANR
LnEmm
mLnaEE
LndEkTL
naELnE
LnE
kT
akTMaxw
21
2
0
)/exp()(2)(
22)(
7Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
Java Implementation Pointwise* ENDF data at 300K in Sigma DB (0K pointwise is in progress) AME2003 in -decay database Java 1.5 Simpson summation of pointwise data splitted into 2 slices, slice width < 10 keV for 26 neutron energy values: kT = 0.001 - 1 MeV Evaluated neutron data for all major libraries: ENDF/B-VII.0, JEFF-3.1, JENDL-3.3, ENDF/B- VI.8 were processed on Windows desktop in 4 - 5 h
*It refers to conversion of resonance parameters into cross sections and to Doppler broadening them by taking into account neutron velocities at room temperature. Applies only to the neutron sublibrary in the resonance region.
8Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
Numeric Integration
Lower & Upper Riemann (Rectangular),
Trapezoidal, Midpoint, Recursive
(Trapezoidal Power Of Two, Romberg,
Simpson ) Simpson integration is prefferable Sigma pointwise libraries were linearized
within 0.1%: m = (1+2)/2
9Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
Maxwellian Cross Sections Java numerical integration performs better than
INTER ENDF utility code Simple trapezoidal MACS for JENDL-3.3 are
within 2-5% from T. Nakagawa et al., ADNDT
91 (2005) 77 calculations based Simpson numerical integration + division
of each slice into 2 + slice width < 10 keV
agrees with Nakagawa et al. within 1% Hybrid (analytical + numerical) integration Bao et al.
10Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
MACS comparison for 151Sm(n,)
U. Abbondanno et al., PRL 93,161103 (2004) K. Wisshak et al., PRC 73, 015802 (2006) Simpson MACS (mb):
Energy, keV 10 15 20 25 30 40 50
PRL (2004) 3100 (160)
PRC (2006) 6082 4704 3925 3407 3031 2510 2158
ENDF/B-VII.0 (2006)
6060 4600 3791 3262 2879 2353 1999
JEFF-3.1 (2005) 6658 5079 4183 3586 3153 2557 2161
JENDL-3.3
(2002)
3987 3086 2583 2249 2005 1663 1430
ENDF/B-VI.8 (2001)
5463 4118 3380 2904 2567 2117 1826
11Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
Reaction Rates Reaction rates for four major libraries have
been calculated Neutron cross sections (30 keV) x Solar
abundances (relative to Si = 106)N ratio:
JENDL-3.3: 122Te:123Te:124Te => 1:0.94:1.03
ENDF/B-VII.0: 122Te:123Te:124Te =>1:1.18:0.9
Covariances => Uncertainties
12Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
Conclusion & Outlook (n,) Maxwellian cross sections and reaction rates have been calculated for four major libraries: ENDF/B-VII.0, JEFF-3.1, JENDL-3.3, ENDF/B-VI.8
Results were compared with: Calculations T. Nakagawa et al. ADNDT 91 (2005) 77 Bao et al. ENDF utility code INTER Neutron cross sections x Solar system abundances
(n,p), (n,), (n,f), (n,2n), (n,t+2) reactions will follow Results will be loaded into Sigma database (Sigma Demonstration for Trento meeting) Future covariances will produce errors for MACS/Reaction Rates
13Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
MACS comparison for 19F(n,) E. Uberseder et al., Phys. Rev. C75,035801
(2007), 44% lower than previous result Simpson MACS (mb) for LA+CNDC+ORNL:
Energy, keV 10 15 20 25 30 40 50
PRC75
(2007)
4.1 4.5 4.2 3.7+-0.1 3.2 2.5 2.0
ENDF/B-VII.0 (2006)
5.4 6.1 5.6 5.0 4.4 3.4 2.7
JEFF-3.1 (2005)
5.4 6.1 5.6 5.0 4.4 3.4 2.7
JENDL-3.3
(2002)
6.5 7.4 7.1 6.4 5.7 4.6 3.8
ENDF/B-VI.8 (2001)
9.6 10.5 9.4 8.1 6.9 5.2 4.0
14Boris Pritychenko Nuclear Physics Data Compilation for Nucleosynthesis Modeling, Trento, May 29 – June 1, 2007
Email from Nakagawa
Dear Boris,
Thank you for your e-mail.
Concerning nuclear masses, we used values given in head records of JENDL-3.3.
I think small discrepancies between our results and yours might be caused byintegration methods. In our calculation for adjacent two cross-section datapoints, a table of Sig(E)*E*exp(-E/kT) was created at fine energy mesh byusing the dividing method originally used in RESEND code. Then integration was made by subroutine ECSI taken from ENDF/B utility codes.
Best regards,Tsuneo