brookhaven science associates u.s. department of energy covariance data: status and perspective at...

Brookhaven Science AssociatesU.S. Department of Energy

Covariance data: Status and Perspective at BNL

D. Rochman, M. W. Herman, P. ObloD. Rochman, M. W. Herman, P. ObložžinskinskýýNational Nuclear Data Center, Brookhaven National LaboratoryNational Nuclear Data Center, Brookhaven National Laboratory

&&

T. KawanoT. KawanoT-16, Los Alamos National LaboratoryT-16, Los Alamos National Laboratory


Methodology for covariance calculations at BNL

Pointwise cross sections (with any energy groups)Pointwise cross sections (with any energy groups)

RRR(Resolved Resonance

Region)

URR(Unresolved

Resonance Region)

FaR(Fast Region)

10-2 10-1 100 101 102 103100

101

102

103

104

EMPIRE + KALMAN

Resonance Module + KALMAN

105 106 107

5

6

7

8

9

10

Cro

ss S

ectio

n (

Ba

rns)

Neutron Energy (eV)


General Procedure

-Fast Region-Hauser Feshbach-Pre-equilibrium-…

-Resonance Region-Breit Wigner-Reich Moore

Models and parameters

ParametersParameters

SensitivitySensitivity

KALMANFilter

an optimal recursive data processing

algorithm

or

Cross SectionCross SectionUncertaintiesUncertainties

and and Cross SectionCross SectionCorrelationsCorrelations

ParametersParameters

UncertaintyUncertainty

RIPL&

Parameter uncertainty adjustment

Optional:Optional:Thermal neutron captureThermal neutron capture

Resonance IntegralResonance Integral


General Procedure

Up to today, this procedure was applied to:

• Gd-152 to Gd-160 from 35 to 500 parameters (R3+URR+FaR)• Am-241 790 parameters (R3+URR)• Tc-99 1600 parameters (R3+URR)• U-233, 234, 236 from 250 to 3850 parameters (R3+URR)

Resonance region Fast RegionBreit Wigner,

Reich Moore models

Compound, pre-equilibrium, direct models

En,n,f 1f2Optical par., -strength func,

level densities …


152Gd(n,): Variance

10-3 10-2 10-1 100 101 102 103 104 105 106 107

1E-3

0.01

0.1

1

10

100

1000

10-3 10-2 10-1 100 101 102 103 104 105 106 107

0

2

4

6

8

10

12

14

16

18

20

22

24

26

28

30

C

ross

Se

ctio

n (

Ba

rns)

Re

lativ

e U

nce

rta

inty

(%

)

Incident Neutron Energy (eV)

Resonance Module + KALMAN EMPIRE + KALMAN SAMMY Retroactive Method Atlas 2006 Wisshak et al.


152Gd(n,): Correlation Energy-Energy

Energy (MeV)

Ene

rgy

(MeV

)

100.10.00110-510-7


155Gd(n,): Variance

10-3 10-2 10-1 100 101 102 103 104 105 106 107

1E-3

0.01

0.1

1

10

100

1000

10000

100000

10-3 10-2 10-1 100 101 102 103 104 105 106 107

0

5

10

15

20

25

30

C

ross

Se

ctio

n (

Ba

rns)

Resonance Module + KALMAN EMPIRE + KALMAN SAMMY Retroactive Method Atlas 2006 Wisshak et al.

Re

lativ

e U

nce

rta

inty

(%

)



157Gd(n,): Correlation Energy-Energy

Energy (MeV)

Ene

rgy

(MeV

)

100.10.00110-510-7


241Am(n,f): Variance

10-3 10-2 10-1 100 101 102 103 104 105 106 107

1E-4

1E-3

0.01

0.1

1

10

100

10-3 10-2 10-1 100 101 102 103 104 105 106 107

0

10

20

30

40

50

60

70

C

ross

Se

ctio

n (

Ba

rns)

241Am(n,f) in 44 energy groups

Resonance Module + KALMAN Atlas 2006

Re

l. U

nc.

(%

)



241Am(n,f), 234U(n,f): Correlation Energy-Energy

234U(n,f)

Energy (MeV) Energy (MeV)241Am(n,f)

10-7 10-5 0.001 10-7 10-5 0.001


236U(n,f) and 99Tc(n,)

Energy (MeV)

236U(n,f) 99Tc(n,)

Energy (MeV)

10-7 10-5 0.00110-7 10-5 0.001


Production Schedule

• May 2006 : proof of principle on 8 Gd isotopes, 241Am, 99Tc, 233U, 234U, 236U

• End 2006 : Codes ready and running on a 10-nodes cluster

• Mid 2007 : Production of covariances for selected materials

• End 2007 : Low fidelity covariances for ENDF/A (if project approved)

Covariance matrix available -in any multi-group representation-at any temperatures-in tabulated form or MF33 format

brookhaven science associates u.s. department of energy covariance data: status and perspective at...

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