The CAB Models for Water: Thermal scattering libraries for ... · evaluation would require to...

THE CAB MODELS FOR WATER:THERMAL SCATTERING LIBRARIES FOR H2O AND D2O

IN THE 283-600 K RANGE

Jose Ignacio Marquez Damian

Neutron Physics DepartmentCentro Atomico Bariloche

Argentina

WPEC SG-42 kick off meetingMay 18th, 2015

NEA Headquarters, Issy-les-Moulineaux, France

J.I. MARQUEZ DAMIAN THE CAB MODELS FOR WATER: THERMAL SCATTERING LIBRARIES FOR H2O AND D2O WPEC SG-42 1 / 28

NEUTRON PHYSICS DEPARTMENT AT CENTRO ATOMICO BARILOCHE

Centro Atomico Bariloche is one of the research centers of the Atomic EnergyCommission of Argentina, and it is located in the south of the country.

The neutron physics department was founded in 1969 by Hector Antunez, one ofthe alumni of the legendary neutron physics group at General Atomics in SanDiego.

The group was formed around a small pulsed neutron source, a 25 MeV electronLinac, similar to the accelerator at RPI.

Now we are 23 people (counting researchers, students and technical staff)working on neutron physics and applications to condensed matter research,materials science and nuclear engineering.

Our main current activity is the development of neutron scattering instrumentsfor the forthcoming RA-10 reactor, which will be similar to the OPAL reactor thatthe Argentine company INVAP built in Australia.


WHO WE ARE: THERMAL SCATTERING NUCLEAR DATA GROUP ATCENTRO ATOMICO BARILOCHE

Rolando Granada Florencia Cantargi Ignacio MarquezScattering theory and

advanced neutron sourcesCold moderator materials

and neutron filtersNuclear reactorapplications andbenchmarking

Past members: Monica Sbaffoni (currently at IAEA), Victor Gillette (currently atUniversity of Sharjah, U.A.E).


WHAT WE DO: SCATTERING KERNELS FOR THERMAL MODERATORS

Material SSF LEAPR Users and collaborators

H2O • • Slovak University of TechnologyCEA Cadarache

D2O • • Canadian Nuclear LaboratoriesCH2 • Chalmers University of TechnologyC6H6 • •Plexiglass • Institute of Nuclear Physics, PolandEthanol •Dowtherm •Metal Hydrides •Dodecane • Century Research Center Corp., JapanTributylphosphate • Century Research Center Corp., JapanMesitylene • Joint Institute of Nuclear Physics, RussiaGraphite • •


WHAT WE DO: SCATTERING KERNELS FOR COLD MODERATORS


Liquid H2 • INVAP S.E., ArgentinaLiquid D2 • INVAP S.E., ArgentinaSolid D2 • Paul Scherrer InstitutLiquid and Solid CH4 • Indiana University, U.S.A.Solid H2O • Bhabha Research Center, India

Hokkaido University, JapanClathrate • JESSICA collaborationSolid Mesitylene • JESSICA collaboration

Joint Institute of Nuclear Physics, RussiaHokkaido University, JapanTRIUMF, CanadaLANL, USA

Mesitylene/Toluene • TRIUMF, CanadaLiquid Ethane •Triphenylmethane •

(See talk SG42-10 by Florencia Cantargi, tomorrow afternoon at 16:00)


WHAT WE DO: SCATTERING KERNELS FOR NEUTRON FILTERS


Silicon • RA-10 reactor project, ArgentinaPaul Scherrer Institut, Switzerland

Sapphire • RA-6 reactor, Argentina• RA-3 reactor, Argentina

Paul Scherrer Institut, SwitzerlandBismuth • RA-6 reactor, ArgentinaSilica • ORNL, U.S.A

(See talk SG42-10 by Florencia Cantargi, tomorrow afternoon at 16:00)


THE CAB EVALUATION FOR WATER: SOME CONTEXT

- In 2008 Rolando proposed to revisit the scattering of neutrons in water, applyingthe recent experience of the group in advanced moderators.

- Red Cullen had recently published the reports How Accurately Can We CalculateNeutrons Slowing Down In Water? and How Accurately can we Calculate ThermalSystems?, which caught our attention.

- We decided it would be a good PhD topic for me, who at that time wasparticipating in the ICSBEP project.


THERMAL SCATTERING MODELSIN THE EVALUATED NUCLEAR LIBRARIES

ENDF/B(CSEWG)

JEF/JEFF(OECD/NEA)

JENDL(JAEA)

ROSFOND(IPPE)

ENDF/B-I(1968)

ENDF/B-V(1979)

ENDF/B-VI.4(1994)

ENDF/B-III(1972)

ENDF/B-II(1970)

ENDF/B-IV(1974)

ENDF/B-VI.0(1990)

JEF-2.2(1992)

JEFF-3.1(2004)

JEF-1(1984)

JEFF-3.0(2002)

JEFF-3.2(2014)

ENDF/B-VI.8(2001)

ENDF/B-VII.1(2011)

ENDF/B-VII.0(2006)

JENDL-1(1977)

JENDL-2(1982)

JENDL-3(1989)

JENDL-3.1(1990)

JENDL-3.2(1994)

JENDL-3.3(2002)

JENDL-4.0(2004)

ROSFOND-2010(2010)

BROND,ABBN

1970 1980 1990 2000 2010

1970 1980 1990 2000 2010


THERMAL SCATTERING MODELSIN THE EVALUATED NUCLEAR LIBRARIES: GENERAL ATOMICS MODEL

ENDF/B(CSEWG)

JEF/JEFF(OECD/NEA)

JENDL(JAEA)

ROSFOND(IPPE)

MacFarlane/LANL(GA Models in LEAPR)

General Atomics(GASKET Models)

ENDF/B-I(1968)

ENDF/B-V(1979)

ENDF/B-VI.4(1994)

ENDF/B-III(1972)

ENDF/B-II(1970)

ENDF/B-IV(1974)

ENDF/B-VI.0(1990)

JEF-2.2(1992)

JEFF-3.1(2004)

JEF-1(1984)

JEFF-3.0(2002)

JEFF-3.2(2014)

ENDF/B-VI.8(2001)

ENDF/B-VII.1(2011)

ENDF/B-VII.0(2006)

JENDL-1(1977)

JENDL-2(1982)

JENDL-3(1989)

JENDL-3.1(1990)

JENDL-3.2(1994)

JENDL-3.3(2002)

JENDL-4.0(2004)

ROSFOND-2010(2010)

BROND,ABBN

1970 1980 1990 2000 2010

1970 1980 1990 2000 2010


THERMAL SCATTERING MODELSIN THE EVALUATED NUCLEAR LIBRARIES: IKE STUTTGART MODEL

ENDF/B(CSEWG)

JEF/JEFF(OECD/NEA)

JENDL(JAEA)

ROSFOND(IPPE)

IAEATSL

IKE Stuttgart(GASKET Models)

IKE Stuttgart(LEAPR Models)



ENDF/B-I(1968)

ENDF/B-V(1979)

ENDF/B-VI.4(1994)

ENDF/B-III(1972)

ENDF/B-II(1970)

ENDF/B-IV(1974)

ENDF/B-VI.0(1990)

JEF-2.2(1992)

JEFF-3.1(2004)

JEF-1(1984)

JEFF-3.0(2002)

JEFF-3.2(2014)

ENDF/B-VI.8(2001)

ENDF/B-VII.1(2011)

ENDF/B-VII.0(2006)

JENDL-1(1977)

JENDL-2(1982)

JENDL-3(1989)

JENDL-3.1(1990)

JENDL-3.2(1994)

JENDL-3.3(2002)

JENDL-4.0(2004)

ROSFOND-2010(2010)

BROND,ABBN

1970 1980 1990 2000 2010

1970 1980 1990 2000 2010


OTHER WATER MODELS(NOT INCLUDED IN THE EVALUATED NUCLEAR LIBRARIES)

ENDF/B(CSEWG)

JEF/JEFF(OECD/NEA)

JENDL(JAEA)

ROSFOND(IPPE)

IAEATSL

IKE Stuttgart(GASKET Models)

IKE Stuttgart(LEAPR Models)


Kyoto University(Fourier transform models)


Centro Atomico Bariloche(Synthetic Scattering Models)

ENDF/B-I(1968)

ENDF/B-V(1979)

ENDF/B-VI.4(1994)

ENDF/B-III(1972)

ENDF/B-II(1970)

ENDF/B-IV(1974)

ENDF/B-VI.0(1990)

JEF-2.2(1992)

JEFF-3.1(2004)

JEF-1(1984)

JEFF-3.0(2002)

JEFF-3.2(2014)

ENDF/B-VI.8(2001)

ENDF/B-VII.1(2011)

ENDF/B-VII.0(2006)

JENDL-1(1977)

JENDL-2(1982)

JENDL-3(1989)

JENDL-3.1(1990)

JENDL-3.2(1994)

JENDL-3.3(2002)

JENDL-4.0(2004)

ROSFOND-2010(2010)

BROND,ABBN

1970 1980 1990 2000 2010

1970 1980 1990 2000 2010


EVALUATION METHODOLOGY: PRINCIPLES

1 Use standard tools to ensure the scattering kernel could be processed in NJOY⇒LEAPR.

2 Use the best available experimental information on water, and complement it withmolecular dynamics. In particular we knew from the work by Marti, Padro andGuardia at UPC that it was possible to compute the frequency spectrum of watercorrectly. As newcomers to molecular dynamics, we started with help from DavidMalaspina from Northwestern University.

3 Include molecular diffusion to improve the quasielastic region. It is not perfect, butit is better than the current models that use free gas, and works out of the box inLEAPR (see 1).

4 Add structural corrections when necessary (deuterium and oxygen) using the Skoldapproximation and structure data from Alan Soper and molecular dynamics.


EVALUATION METHODOLOGY: WHY LEAPR?

- Aside of being the standard, there is a big problem when looking at alternatives toLEAPR: the wide dynamic range involved:

- An ENDF-6 standard thermal scattering evaluation should work in a wide incidentenergy range: from Ein = 10−5 eV to 5-10 eV.

- Representing the angular distribution from Ein = 10−5 eV requires a scattering vectorsfrom ∼ 0.150 A−1 to ∼ 150 A.

- The quasielastic peak width at Q = 0.150 A−1 is }DQ2 ' 30× 10−9 eV. If we discretizethat peak using ten points, the required ε = }ω range goes from 3× 10−9 eV to 10 eV.

- As an alternative, we did compute S(Q, ω) as a Fourier transform in time andspace of G(r, t) for limited ranges of Q and }ω. But a full (ENDF-6 compatible)evaluation would require to compute G(r, t) in a timescale from 0.1 fs to 10µs (1010

timesteps!).

- We decided to stick with LEAPR until we find (or develop) something better.


EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File

Velocity Autocorrelation Function

Generalized Frequency Spectrum

LEAPR Model

Thermal Scattering Library

Validation and Benchmarking


EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model




EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model



Three NPT equilibration runs: - with Berenden thermostat and barostat - with Berendsen thermostat and Parinello-Rahman barostat - with Nose-Hoover thermostat and Parinello-Rahman barostat

NVE production run:


EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model



100 ps with velocity vector saved every 6 frames: ~ 8 Gb


EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model



0 0.1 0.2 0.3 0.4 0.5Time [ps]

-4

-2

0

2

4

6

8

Vel

ocity

Aut

ocor

rela

tion

Func

tion,

VA

CF

[nm

2 /ps2 ]

Velocity autocorrelation function computed with g_velacc_d


EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model



0 100 200 300 400 500Energy [meV]

0

0.002

0.004

0.006

0.008

0.01

Gen

eral

ized

freq

uenc

y sp

ectr

um [m

eV-1

]

TIP4P/2005fBellissent-Funel

Generalized frequency spectrum for H bound in H2O at room temperature, computed from molecular dynamics. Arrows mark the internal vibrational modes as measured by Lappi.


EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model



Parameters for the LEAPR model for H bound in H2O at 293 K

0 0.1 0.2 0.3 0.4 0.5Energy

0

2

4

6

8

10

Freq

uenc

y sp

ectr

um [e

V-1

]

ε1 = 0.205 eV

ε2 = 0.415 eV

w1 = 0.15667

w2 = 0.31333

wt = 0.07918

c = 3.969

wc = 0.52208


EVALUATION WORKFLOW

0 5 10 15 20 25Q [A-1]

0

0.5

1

1.5

2

2.5

3

Skol

d co

rrec

tion

fact

or, S

(Q)

Deuterium @ 293KOxygen @ 293 K

Scoh(α,β) = Sinc(α/S(Q),β)S(Q)

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model



Sköld correction factors for deuterium and oxygen bound in D2O


EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model



Log plot of the symmetric for deuterium bound in heavy water


EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model



Detail of the quasielastic peak.


EVALUATION WORKFLOW

Water Model

Molecular Dynamics

TRR Trajectory File



LEAPR Model



Frequency spectrum

Double differential cross section

Differential cross section(angular distributions)

Total cross section

Average cosine angle, diffusion coeff.

Benchmarks

Dif

fere

nti

al, c

lose

r to

th

e p

hys

ics

Inte

gral

, clo

ser

to t

he

app

lica

tion

s

(I will cover this in detail in my SG-40 talk tomorrow morning)


EVALUATION: LIBRARY FILES

Using this methodology we evaluated the thermal scattering law for hydrogen boundin light water and for deuterium and oxygen in heavy water from 283 to 600 K.The libraries are available in ENDF-6 and ACE format in the webpage of the NeutronPhysics Department:

http://www2.cab.cnea.gov.ar/˜nyr/tsl_eng.html


http://www2.cab.cnea.gov.ar/~nyr/tsl_eng.html

ACTIVE COLLABORATIONS RELATED TO THIS PROJECT

Around this project we developed an collaboration network with internationalpartners:

- Danila Roubtsov, from Canadian Nuclear Laboratories: library processing andrefinement; validation with criticality safety and reactor physics benchmarks (seetalk SG42-11 tomorrow morning at 9:30)

- Gilles Noguere and Juan Pablo Scotta from CEA/Cadarache: application to lightwater reactors and covariance matrix calculations (see talk SG40-12 tomorrowmorning at 11:00).

- David Baxter from Indiana University: total cross section measurements for lightand heavy water at LENS (see talk SG42-6 tomorrow afternoon at 15:30).


SUMMARY AND CONCLUSIONS

- The Neutron Physics Department at Centro Atomico Bariloche has more than 40years of continuous experience working in neutron scattering applied to nucleardata and nuclear engineering.

- During the past 6 years our group has been working on a new evaluation of thethermal scattering law for light and heavy water. As I will show tomorrowmorning, these evaluations are an improvement over existing evaluations.

- The libraries are available for downloading at our website, and we encourage youto use them and give us feedback. We look forward to do the required work tomake these evaluations available in the evaluated nuclear data libraries.

- Surrounding this work we developed a collaboration network with diverseexpertise and common interest in neutron scattering libraries.


THANKS FOR YOUR TIME.

BARILOCHE, ARGENTINA

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