boris pritychenko nuclear physics data compilation for nucleosynthesis modeling, trento, may 29 –...

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


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


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


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


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)(


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.


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


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.


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


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


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


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


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

boris pritychenko nuclear physics data compilation for nucleosynthesis modeling, trento, may 29 –...

Documents

neutron data

nuclear data file endf

nuclear industry

nuclear astrophysics

evaluated recommended

nucleosynthesis modeling

core nuclear reaction

project motivation endf