y. danon rensselaer polytechnic institute, troy, …€¢ z. blain • r. bahran • m. rapp ......

Mechanical, Aerospace and Nuclear Engineering nacThe Gaerttner Laboratory

The Nuclear Data Program at Rensselaer Y. Danon

Rensselaer Polytechnic Institute, Troy, NY 12180, USA

EFNUDAT 2010, Paris


Collaboration Rensselaer Polytechnic Institute, Troy, NY, USA

Faculty: Dr. Y. Danon

PhD. Students: Z. Blain R. Bahran M. Rapp J. Thompson D. Williams

Bechtel Marine Propulsion Corporation, Knolls Atomic Power Laboratory Dr. G. Leinweber Dr. D.P Barry Dr. R.C Block J. Hoole


Outline The Facility Resonance Region

Neutron Transmission Measurements Neutron Capture Measurements Capture to Fission Ratio Neutron Resonance Scattering

High Energy (0.5 MeV- 20 MeV) Neutron Transmission Measurements Neutron Scattering Measurements

Filtered Beam Measurements The Lead Slowing Down Spectrometer


The RPI LINAC Facility

Started operation in 1961 60 MeV electron LINAC Pulsed width from 5 ns to 5 ms Neutron production by (g,n) reactions in Ta Flight Paths lengths ranging from 15m to 250m Graduated over 160 student who utilized the

LINAC as part of their PhD theses research.


The RPI LINAC Facility

OFFICE

OFFICEOFFICE

OFFICEOFFICE

OFFICEOFFICEOFFICEOFFICE

SERVICE ROOM

BUTLER

BR

BR

SHOP AREA

BUILDING

HOT LABORATORY

DARKROOM

CONTROLROOM NEEP LAB

STORAGEROOM

ROOMTARGET

ACCELERATORROOM

ROOMMODULATOR

NICELAB

25-METER STATION

WEST

EAST

ROOMTARGET

ACCELERATORROOM

25-METER STATION

WEST

EAST

N

GAERTTNER LINAC LABORATORY

INSTITUTERENSSELAER POLYTECHNIC

N



HOT

ROOMTARGET

ACCELERATORROOM

NICELAB

25-METER STATION

WEST

EAST

ROOMTARGET

ACCELERATORROOM

25-METER STATION

100-METER STATION

250-METER STATION

WEST

EAST

N



N



N



30 PORT

ENERGY ANALYZING MAGNET

He FLIGHT PATH

15-METER

DETECTORTRANSMISSION

CAPTUREDETECTOR

DETECTORTRANSMISSION

AUXILLARYEQUIPMENTROOM

Bent/TiltFocus

SPECTROMETERLEAD SLOWING DOWN

LSDS

100m250m 15-35m

~4 X 1013 neutrons/sec 1- 500 Hz 6-5000ns pulse width


Neutron Producing Targets

Enhanced Thermal Target

Bare Bounce Epithermal Target


Detectors

Transmission

Capture/multiplicity

Scattering

25m

30m


Current Activity Time of flight measurements

Resonance Region Capture (0.01 eV 2 keV) Transmission (0.001 eV 100 KeV) Capture to fission ratio (alpha)

High energy (0.4-20MeV) Scattering (30 m flight path) Transmission (100m and 250m flight path) Fission spectra and nubar

High accuracy total cross section measurements using filtered beams Resonance scattering

Lead Slowing Down Spectrometer Simultaneous measurement of fission cross sections and fission fragment mass

and energy distributions using the RPI lead slowing down spectrometer Measurements of energy dependent (n,p) and (n,a) cross sections of nanogram

quantities of short-lived isotopes. (collaboration with LANL).


Resonance Region DetectorsLi-Glass Detector at 25m 2 cm B4C Liner (98.4 atom% 10B)

Sample

~20 liter of NaI(Tl)


Transmission Experiment

Li-Glass Neutron DetectorNeutron Beam

Neutron Beam

Sample

)exp(Out Sample

In SampletNC

CT s-==

N Number density [atoms/barn]st Total cross section

Li-Glass Neutron Detector

Two Experiments:1. Sample Out

2. Sample In


Capture Experiments

Gamma RaysNeutron Beam

Multiplicity Detector

( ) mst

t YNY +--= ss

s g)exp(1

The capture Yield:

Sample

hfYCounts =f neutron fluxh detection efficiency


Resonance Cross Section Measurements and Data Analysis

Data Reduction

Experiment

Data Analysis

CollectTransmission Data

ThermalData & Background

EpithermalData & background

Reduce toTransmission

2-5 samples

Fit DataSAMMY code

CollectCapture Data

ThermalData, Background &

Flux

EpithermalData, background &

Flux

Reduce toCapture Yield

2-5 samples

Resonaceparameters

Various Parameters

( )( )iopenopeni

isamplesamplei

i tBkRtBkR

T-

-= h

fi

bkgi

samplei

iRRY -=


Elemental Molybdenum

0 50 100 150 2000.00.20.40.60.81.0

0 50 100 150 200

0.00.20.40.60.81.0

0 50 100 150 200

1E-3

0.01

0.1

0.5

Tran

smis

sion 200-mil Mo SAMMY calc

100-mil Mo SAMMY calc 50-mil Mo SAMMY calc 25-mil Mo SAMMY calc 10-mil Mo SAMMY calc 5-mil SAMMY calc ENDF/B-VI.8 200-mil ENDF/B-VII 200-mil

Energy, eV

Tran

smis

sion

250-mil Mo SAMMY calc ENDF/B-VII.0 250-mil ENDF/B-VI.8 250-mil 100-mil Mo SAMMY calc

Capt

ure

Yiel

d

20-mil Mo SAMMY calc ENDF/B-VII.0 20-mil ENDF/B-VI.8 20-mil 10-mil Mo SAMMY calc 5-mil Mo SAMMY calc 2-mil Mo SAMMY calc

G Leinweber, DP Barry, JA Burke, NJ Drindak, RC Block, Y Danon, BE Moretti, Resonance Parameters and Their Uncertainties Derived from Epithermal Neutron Capture and Transmission Measurements of Elemental Molybdenum, Nuclear Science And Engineering, 164, 287-303, (2010)


Elemental Molybdenum 120 eV - 145 eV

120 125 130 135 140 1450.00

0.05

0.10

0.15

0.200.000.200.400.600.801.00

Capt

ure

Yiel

d

Energy [eV]

20-mil Mo 10-mil Mo 5-mil Mo 2-mil Mo SAMMY calc ENDF/B-VII.0 20-mil

Tran

smiss

ion

200-mil Mo 100-mil Mo 50-mil Mo 25-mil Mo 10-mil Mo 5-mil SAMMY Fit ENDF/B-VII 200-mil


Gd Transmission and Capture

0 50 100 150 200 250 300-0.050.000.050.100.150.200.250.300.350.400.45

0 50 100 150 200 250 300-0.10.00.10.20.30.40.50.60.70.80.91.01.1

0.127-mm Data SAMMY fit

Capt

ure

Yiel

d

Energy, eV

1.27-mm Data SAMMY fit

Tran

smiss

ion

Energy, eV

G. Leinweber, D.P. Barry, M.J. Trobovich, J.A. Burke, N.J. Drindak, , HD Knox, RV Ballad, R.C. Block, Y. Danon, L.I. Severnyak, Neutron Capture and Total Cross-Section Measurements and Resonance Parameters of Gadolinium,. Nuc. Sci Eng.154, 261-279 (2006).


New Gd Resonances

200 205 210 215 220 225-0.10.00.10.20.30.40.50.60.70.80.91.0200 205 210 215 220 225

-0.10.00.10.20.30.40.50.60.7

0.508-mm Data 0.889-mm Data 1.27-mm Data 2.54-mm Data 5.08-mm Data 1.02-cm Data SAMMY fit ENDF 1.02-cm

Tran

smiss

ion

Energy [eV]

0.051-mm Data 0.127-mm Data 2.54-mm Data SAMMY fit ENDF

Capt

ure

Yiel

d


155,157Gd Thermal Region - Separated Isotopes

0.002 0.01 0.1 1-0.10.00.10.20.30.40.50.60.70.80.91.01.11.2

0.002 0.01 0.1 1-0.10.00.10.20.30.40.50.60.70.80.91.01.11.2

Energy [eV]

Tran

smiss

ion

LX-2 155Gd LX-4b 155Gd LX-5 157Gd LX-7 157Gd 0.025-mm metal 0.051-mm metal SAMMY fit

Capt

ure

Yiel

d

LX-4 155Gd LX-9 155Gd LX-10 157Gd LX-11 157Gd SAMMY fit

0.02 0.03 0.04 0.05-0.10.00.10.20.30.40.50.60.70.80.91.0

0.02 0.03 0.04 0.05-0.10.00.10.20.30.40.50.60.70.80.91.01.11.2

Capt

ure

Yiel

d

LX-9 155Gd LX-10 157Gd RPI ENDF

Energy [eV]

Tran

smiss

ion

LX-4b 155Gd LX-7 157Gd 0.025-mm metal RPI ENDF


New 155,156,157,158,160Gd Capture Measurements

Many new resonances observed200 300 400 500 600 700 800 900 1000

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

Gd-157 RPI Data ENDF/B-7.0

Capt

ure

Yiel

dEnergy [eV]

Not in ENDF

100 200 300 400 500 600 700 800 900 10000.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

Gd-155 RPI Data ENDF/B-7.0

Capt

ure

Yiel

d

Energy [eV]

Not in ENDF

Yeong-Rok Kang, Tae-TK Ro, Taofeng Wang, Sung-shul Yang, Manwoo Lee, Guinyun Kim, Jong-Hwan Lee, Robert Block, Devin Barry and Yaron Danon, Neutron Capture Measurements and Parameters of Gadolinium, International Conference on Nuclear Data for Science and Technology (ND2010), Korea, 26-30 April, 2010


Thermal Total Cross Section of Natural Cd - I

The transmission and capture data are in very good agreement

The data is in good agreement with ENDF/B-VI.8 elemental but not with the isotopic ENDF/B-VI.8 and ENDF/B-VII.0

Surprisingly there are not many measurements of the thermal value.

0.01 0.1 10

1000

2000

3000

4000

5000

6000

7000

8000 RPI-Transmission 2 mil sample RPI-Transmission 4 mil sample RPI-Transmission 20 mil RPI-Capture 2 mil sample RPI-Capture 4 mil sample ENDF/B-6.8 from istopes ENDF/B-7.0 from istopes ENDF/B-6.8 Elemental

s t (b

arns

)

Energy (eV)


Thermal Total Cross Section of Natural Cd - II

0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.102000

2500

3000

3500

4000 RPI-Transmission 2 mil sample RPI-Transmission 4 mil sample RPI-Transmission 20 mil RPI-Capture 2 mil sample RPI-Capture 4 mil sample ENDF/B-6.8 from istopes ENDF/B-7.0 from istopes ENDF/B-6.8 Elemental

s t

(bar

ns)

Energy (eV)

~5% difference in 0.0253 eV !!!


Eu Transmission compared to ENDF/B-7.0

10 2 4 6 8 10 12 14 16 18 200.0

0.2

0.4

0.6

0.8

1.0

1.2 1 2 4 6 8 10 12 14 16 18 200.0

0.2

0.4

0.6

0.8

1.0

1.2

Tran

smiss

sion

Energy [eV]

40 mil elemental Eu ENDF/B-7.0

Tran

smiss

ion

RPI data 15 mil 153Eu ENDF/B-7.0

50 60 70 80 90 100 110 120 130 140 1500.0

0.2

0.4

0.6

0.8

1.0

1.250 60 70 80 90 100 110 120 130 140 1500.0

0.2

0.4

0.6

0.8

1.0

1.2

Tran

smiss

sion

Energy [eV]

40 mil elemental Eu ENDF/B-7.0

Tran

smiss

ion

RPI data 15 mil 153Eu ENDF/B-7.0

153Eu

Elemental Eu


High Resolution Transmission Detector Modular Li-Glass detector at 100m flight path

Extends our capabilities to the unresolved resonance region Qualification measurements in progress.

Neutron Beam

6Li-Glass


235U Alpha Measurements

Place a 235U sample in the multiplicity detector

Measurements with 235U samples Use the multiplicity information Use data above and below neutron binding

energy

B.EFission + Capture Fission

g energy


Simultaneous Measurement of the Fission And Capture Cross Section of 235U

10-4

10-3

10-2

10-15x10-1

0 5 10 15 20 25 30 35 40 45 5010-4

10-3

10-2

10-15x10-1

Y g

Capture Exp SAMMY

Y f

Neutron Energy [eV]

Fission Exp SAMMY

10-3

10-2

10-15x10-1

0.01 0.1 110-2

10-1

5x10-1

Y g

Capture Exp SAMMY

Y f

Neutron Energy [eV]

Fission Exp SAMMY


Resonance Scattering Experiment Motivation Provide a benchmark to the model Developed by Dagan et al.

Current MC codes have a poor approximation of the scattering kernel in the vicinity of a resonance.

Use the Time-Of-Flight (TOF) method The TOF will correspond to the scattered neutron energy Scattering in forward and backward scattering angles can be measured

Electron Beam

NeutronProducing Target

238U sample

Good Collimation Neutron Detector

~25.5 m

n

q


Experimental Setup

SampleBlank

Ta Targete- beam line

Moderator


Measured Data

Thick Sample time-of flight spectrum forwards scattering

100 200 300 400 500 600 700 800 900 1000

200

400

600

800

1000

1200

1400

1600

1800

2000

280 290 300 310 320 330 3400

200

400

600

800

1000

6.671 eV

20.972 eV

Coun

ts

TOF [ms]

238U Thick sample Background (no sample)

36.68 eV

TOF [ms]

Cou

nts


34 35 36 37 38 39 400

100

200

300

400

500

RPI Experiment MCNP (unchanged) MCNP (modified) MCNP+S(a,b)

Coun

ts

Scattered Neutron Energy [eV]

E0=36.68 eV

Sample thickness=1/8"

Results - 238U ScatteringBACK FRONT

ThickSample

ThinSample

34 35 36 37 38 39 400

100

200

300

400

500

Experiment MCNP (Modified) MCNP+S(a,b)

Coun

ts


E0=36.68 eVSample thickness=1/16"

BACK FRONT

34 35 36 37 38 39 400

200

400

600

800

1000

Sample thickness=1/8"

Experiment MCNP (Unchanged) MCNP (Modified) MCNP+S(a,b) Geant 4

Coun

ts


E0=36.68 eV

34 35 36 37 38 39 400

100

200

300

400

500

Experiment MCNP (Modified) MCNP+S (a,b)

Coun

ts


E0=36.68 eV

Sample thickness ~1/16"


Other Resonances (Back Scattering)

19 20 21 22 230

100

200

300

400

20.872 eV ResonaceSample thickness=1/8"

RPI Experiment MCNP (Unchanged) MCNP (Modified) MCNP+S(a,b)

Coun

ts


31.0=GGn

Y. Danon, E. Liu, D. Barry, T. Ro, R. Dagan, Benchmark Experiment of Neutron Resonance Scattering Models In Monte Carlo Codes, International Conference on Mathematics, Computational Methods & Reactor Physics (M&C 2009), Saratoga Springs, New York, May 3-7, 2009, on CD-ROM, American Nuclear Society, LaGrange Park, IL (2009).


High Energy Transmission Experimental Setup

Graphite Samples

33

137 5

Nominal thickness in cm

Collimation Collimation Collimation

WaterCooled Ta

TargetSample EJ-301 Liquid Scintillator

Modular Detector

99.93m

91 cm60 cm


Background Determination

MCNP was used to simulate background due to neutron capture interactions with the detector

2.2 MeV photons from hydrogen neutron capture were tallied in the detector volume as a function of time

The MCNP tally was normalized to the exponentially decaying portion of the collected data (t>20 ms)

The MCNP results were fitted to a pulse shape curve

18


Graphite Transmission

0.5 1 10 200.0

0.2

0.4

0.6

0.8

Data - 7 cm Data - 13 cm Data - 33 cm ENDF/B-7.0 - 7 cm ENDF/B-7.0 - 13 cm ENDF/B-7.0 - 33 cm

Tran

smiss

ion

Neutron Energy [MeV]


Results Carbon Total Cross Section

0.5 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.00.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.00.5

1.0

1.5

2.0

2.5

3.0

Cros

s Se

ctio

n (b

)

Energy (MeV)

7 cm 13 cm ENDF/B-7.0

Cros

s Se

ctio

n (b

)

Energy (MeV)

7 cm 13 cm ENDF/B-7.0


Beryllium Transmission

0.5 1 100.0

0.2

0.4

0.6

0.8

1.0

Be 2 cm Be 4 cm Be 8 cm ENDF/B-VII.0 JENDL3.3

Tran

smiss

ion

Energy [eV]15

2348

Beryllium samplesSample thickness is given in cm

Reconfigured the detector with two units to reduce background

M. Rapp, Y. Danon, R. C. Block, F. Saglime, R. Bahran, G. Leinweber, D. P. Barry, N. Drindak, High Energy Neutron Time of Flight Measurements of Carbon and Beryllium Samples at the RPI LINAC, International Conference on Mathematics, Computational Methods & Reactor Physics (M&C 2009), Saratoga Springs, New York, May 3-7, 2009, on CD-ROM, American Nuclear Society, LaGrange Park, IL (2009)


Beryllium Total Cross Section (Low Energy)

0.4 0.5 0.6 0.7 0.8 0.9 1.03

4

5

6

7

8

2 cm sample 4 cm sample Filtered Beam experiment ENDF/B-VI.8 ENDF/B-VII.0 JENDEL 3.2

Cr

oss

Sect

ion

[bar

n]

Energy [MeV]


Mo Total Cross Section

0.4 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.02

3

4

5

6

7

8

9

10

Cros

s Se

ctio

n (b

)

Energy (MeV)

Natural Mo RPI-3 cm sample RPI-8 cm sample RPI-Filtered beam ENDF/B-VII.0 ENDF/BVI.8

M. Rapp, Y. Danon, F. Saglime, Rian Bahran, Robert Block, Greg Leinweber, Devin Barry, Jeff Hoole, Molybdenum and Zirconium Neutron Total Cross Section Measurements in the Energy Range of 0.5 to 20 MeV, International Conference on Nuclear Data for Science and Technology (ND2010), Korea, 26-30 April, 2010


Mo Total Cross Section Below 1 MeV

Notice the visible structure in the cross section

Better agreement with ENDF/B-VII.0. below 0.8 MeV

Should ENDF evaluations include some of this structure ?

The filtered beam transmission data is in good agreement with the transmission data

0.5 0.6 0.7 0.8 0.9 1.06.0

6.5

7.0

7.5

8.0

8.5

9.0

Cros

s Se

ctio

n (b

)

Energy (MeV)

Natural Mo RPI-3 cm sample RPI-8 cm sample RPI-Filtered beam ENDF/B-VII.0 ENDF/BVI.8


Zr Total Cross Section Measurements (0.5-20 MeV)

Used low Hf (less than 100 ppm) Zr metal ENDF/B 6.8 seems like a better fit for E


Ti Total Cross Section Measurements (0.5-20 MeV)

The evaluation are generally in good agreement with the data Below 2 MeV the data has better energy resolution than the evaluation

0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.00

1

2

3

4

5

6

s t [b

arn]

Energy [MeV]

RPI Experiment ENDF/B-6.8 ENDF/B-7.0 JEFF 3.1 JENDL 3.3

4 6 8 10 12 14 16 18 202.0

2.5

3.0

3.5

4.0

s t [b

arn]

Energy [MeV]

RPI Experiment ENDF/B-6.8 ENDF/B-7.0 JEFF 3.1 JENDL 3.3


Ti Total Cross Section Measurements 0.5-1 MeV energy region

The ENDF/B 6.8 and JEFF3.1 evaluations seem to have an energy shift.

ENDF/B-7.0 and JENDL 3.3 are similar and seem to be based on low resolution measurements

0.60 0.65 0.70 0.75 0.800

1

2

3

4

5

6

7

s t [b

arn]

Energy [MeV]

RPI Experiment ENDF/B-6.8 ENDF/B-7.0 (=JEFF 3.1) JEFF 3.1 JENDL 3.3


Tantalum

Deviations from ENDF/B-7.0 and JENDL-3.3 below 3 MeV RPI measurement agrees with other experimental data

2 4 6 8 10 12 14 16 18 204

5

6

7

8

Cros

s Se

ctio

n [b

arn]

Energy [MeV]

Ta ENDF/B-7.0 JENDL-3.3 RPI

2 4 6 8 10 12 14 16 18 204

5

6

7

8

Cros

s Se

ctio

n [b

arn]

Energy [MeV]

RPI (2008) Finlay (1993) P.Poenitz, (1981)


TALYS vs EMPIRE

TALYS and EMPIRE calculations with default parameters for Zr and Mo are in agreement with the data

For Ta and E


Fast Neutron Scattering Detector Array


Scattering Detection System:Experimental Setup

Data Acquisition System Main DAQ Computer (HAL) 25m Station PCI Extension Chassis

Acqiris AP240 DAQ Boards(2 Channels per Board)

Data Processing System Data Processing Computer (SAL) Control

Room Computer Controlled Power Supply

Chassis - SY 3527 Board - A1733N Detector Array

8 EJ301 Liquid Scintillation Detectors Detector Stands

Sample Holder / Changer

Neutron Beam

Detector Array

Acqiris AP240 DAQ Board

PCI Chassis Extention

CAEN ComputerControlled Power Supply

PrinterHAL

Dell -Precision

670

SAL

Data Analysis Computer(Control Room)

Data CollectionComputer

(25m Station Room)


Gamma Background Reduction by Pulse Shape Analysis

Gamma Ray Background Neutron Time of Flight


Scattering Setup Illustration

26

154 90

Pulsed Neutron Beam

7 cm thick Graphite Target

0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5

Time of Flight (nsec)

Cou

nts/

Cha

nnel

Energy (MeV) at 30.1m

26deg

Experimental DataSimulation with ENDF7

0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


90deg


0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


154deg



Carbon Experimental Results (Validation)7cm

0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


154deg


0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


90deg


0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


140deg


0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


119deg


0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


72deg


0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


52deg


0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


26deg


0 500 1000 1500 2000 2500 3000 3500 40000

200

400

600

800

1000

1200

140012510100 0.30.5


Cou

nts/

Cha

nnel


107deg



Beryllium Experimental Results

4cm

8cm

0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


140deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


90deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


52deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


26deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


140deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


90deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


52deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


26deg



Molybdenum Experimental Results

5cm

0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

6000

700012510100 0.30.5


Cou

nts/

Cha

nnel


140deg

Experimental DataENDF6.8JEFF3.1ENDF7.0

0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

6000

700012510100 0.30.5


Cou

nts/

Cha

nnel


90deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

6000

700012510100 0.30.5


Cou

nts/

Cha

nnel


52deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

6000

700012510100 0.30.5


Cou

nts/

Cha

nnel


26deg


8cm

0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


140deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


90deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


52deg


0 500 1000 1500 2000 2500 3000 3500 40000

1000

2000

3000

4000

5000

600012510100 0.30.5


Cou

nts/

Cha

nnel


26deg



10 100 10003

4

5

6

7

8

JEFF-3.1 ENDF/B-6.8 JENDL-3.3 ENDF/B-7.0 CENDL-2

Cros

s Se

ctio

n [b

arn]

Energy [keV]

High Precision Cross Section Measurements Using Filtered BeamsMotivation - Beryllium Total Cross Section

Notice the evaluations were forced through the 24 KeV point of Block et al.R.C.Block, Y.Fujita, K.Kobayashi, T.Oosaki, Precision neutron total cross-section measurements Near 24 kev, J. of Nuclear Science and Technology, Tokyo Vol.12, p.1, 1975


Iron Filter Experimental Setup

Collimation Collimation Collimation

WaterCooled Ta

Target30 cm Fe Sample

Li-Glass NeutronDetector

25.55m.


Natural Iron Filter

10 100 10000.1

1

10

1000.0

0.2

0.4

0.6

0.8

s t [b

arn]

Energy [keV]

30 cm Natural Iron

Tra

nsm

issio

n


Experimental Data Iron filtered beam data

Peaks are broadened by the TOF resolution function High signal-to-background ratio

2 4 6 8 10 12 140

1000

2000

3000

4000

5000

6000

7000

8000

4.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4 5.6 5.8 6.00

1000

2000

3000

4000

5000

6000

7000

8000

Coun

ts

TOF [ms]

g flash


Results - Graphite

100 200 300 400 500 600 700 800 900 1000 11002.5

3.0

3.5

4.0

4.5

5.0 100 200 300 400 500 600 700 800 900 1000 1100-0.02

-0.01

0.00

0.01

0.02

Cros

s Se

ctio

n [b

arn]

Energy [keV]

Graphite total cross section RPI (7cm sample) ENDF/B-VII.0

(R

PI-E

NDF)

/RPI

Statistical Error


Be TransmissionSample thickness and time split was selected according to:

200 400 600 800 10000.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

Energy [keV]

2 cm Be 3 cm Be 5 cm Be ENDF/B-VII.0 2 cm ENDF/B-VII.0 3 cm ENDF/B-VII.0 5 cm

Tran

smiss

ion

Yaron Danon and R. C. Block, Minimizing The Statistical Error of Resonance Parameters and Cross Sections Derived from Transmission Measurements, Nuclear Instruments and Methods A, Vol. 485, 585-595 June, (2002).


Results - Beryllium

10 100 10003

4

5

6

7

8

RPI 2cm RPI 3cm RPI 5 cm JEFF-3.1 ENDF/B-6.8 JENDL-3.3 ENDF/B-7.0

Cros

s Se

ctio

n [b

arn]

Energy [keV]Y. Danon , R. C. Block, M. J. Rapp, and F. J. Saglime, G. Leinweber, D. P. Barry, N. J. Drindak and J. G. Hoole, Beryllium and Graphite High Accuracy Total Cross-Section Measurements in the Energy Range from 24 keV to 900 keV, Nuclear Science And Engineering, 161, 321330, (2009).


Lead Slowing Down Spectrometer


VacuumTi WindowElectronBeam

He Filled Drift Section

Neutron Source(He cooled Ta Target)

LEAD

Crossed I beam + Li2Co3

180 cm

180

cm

Fission Chamber

Flux Monitor

Flux Monitor

Flux Monitor

Tantalum target in the center produces neutrons.

Neutrons scatter elastically with the Pb.

Neutrons can pass through the same position several times.

About 103-104times higher flux than an equivalent flight path TOF experiment (5.6m).

(60 cm from corner)

Lead Slowing-down Spectrometer at RPI

67 tons of Pb


Objectives Simultaneous measurement of the fission cross

section and fission fragment mass and energy distributions of small samples (~nanograms).

Use the RPI lead slowing down spectrometer and a double gridded fission chamber.

Samples are deposited on very thin backing (120 nm thick polyimide with 15 nm gold coating)

Fission Fragment Kinematics


SETUP

Anode

Anode

Cathode

Sample

CH4 Inlet

Filter

FilterTeflon rods

q

e- e-

e- e-

+ + +

+

Grid

Grid

DGGV486

CFDV812

AmplifierN568B

FIFON401

FIFO

FIFO

FIFO

FIFO

FIFO

FIFO

CFD1

CFD2

CFD3

DGG1

ADCV785

TDCV775

ScalerV830

Start

Stop1

Stop2

DGG2

DGG3

Reset/Start

TRG

LINAC Pretrigger

10 MHzClock

IN1

ADC1

ADC6

ADC5

ADC4

Gate

ADC3

ADC2

Preamplifiers

VMEMM

Fission Chamber

Cathode

Anode-1

Anode-2

Grid-1

Grid-1-3.0 KV

-1.5KV-1.5 KV

Double Gridded Fission Chamber

Multiparameter DAQ

In collaboration with LANL and BRC 237U Fission cross sections. (n,a), (n,p) measurements on small samples.


Results Fission Fragment Mass distribution En


Results Fission Fragment Energy DistributionEn


0 1 2 3 4 5 6 7 8 9 10 11-0.5

0.0

0.5

1.0

1.5

2.0

2.5

(V/P

) reso

nanc

e/(V/

P)th

erm

al

Resonance Number

Current Data Hambsch Data Faler Data or Nasuhoglu

235U Fission symmetry in resonance clusters

10-1 100 101 102 103 104100

101

102

103 Current Data ENDF/B-VII.0

thermal 1


239Pu - Results

80 100 120 140 160150

160

170

180

190

200

210

Mass [amu]

TKE

[MeV

]

0.00

0.02

0.04

0.06

0.00

0.02

0.04

0.06

0.00

0.02

0.04

0.06

60 80 100 120 140 1600.00

0.02

0.04

0.06

60 80 100 120 140 160

0.00

0.02

0.04

0.06

Region 2

Region 3

Region 4

Yiel

d (1

/am

u)

Region 5

Region 6

Yiel

d (1

/am

u)

Region 7

Mass (amu)

Yiel

d (1

/am

u)

Mass (amu)

Region 9

Region 10high energy

Yiel

d (1

/am

u)

Yiel

d (1

/am

u)

Region 1 Thermal

Region 8

E


Results Measured Fission Cross Section

10-1 100 101 102 103 104 105100101102103100

101

102

103

239Pu This Experiment Broadened ENDF-7.0

s f [b

arn]

Energy [eV]

235U This Experiment RPI 1993

s f [b

arn]


(n,a) and (n,p) Cross section Measurements Relevant to astrophysics

Can use very small samples (nanograms) or small cross section

The energy range and resolution in the LSDS provides data that can be used to produce Maxwellian averaged cross sections.

Develop a detector Compensated, to suppress the effect of the gamma flash Sensitive to alpha but can also work in noisy RF environment. Not sensitive to gamma background (from inelastic scattering

in Pb)


Compensated PIPS Detector Gamma discrimination

by recording the gamma spectra on two face to face detectors

Digital DAQ collects a bipolar signal

Correct for background by subtracting the bare detector signal from the sample detector on an event by event basis

Sample

Sample Position

PIPSDet.

PIPSDet.

BNC Model555

Ch A

Ch B

Ch D

Ch C

Ext

5MW

5MW

5MW

45ns Cramtemodel 110

Pre-Amplifier

100ns Crematmodel 200

Shaper Amplifier

PhillipsScientific

Model #460Inverting

Transformer(Modifier)

PhillipsScientific

Model #460Inverting

Transformer

4.7nF4.7nF

4.7nF 4.7nF

4.7nF

4.7nF

Tabor Model8024

FunctionGeneratorOut

Trig InNHQ 204M

HVPS (+20V)

Acqiris DC440DigitizerCh 1

Ch 2

I/O A

I/O B

LINACTrigger


Measurement of (n,a) cross section of 147Sm

The motivation was to demonstrate the ability to measure small cross section of small sample with the LSDS

Used 8.25 mg of 147Sm (98.03% enriched Sm)

Our data agrees with the resolution broadened Gledenov measurement better than ENDF/B 7.0

Gledenov et al., Phys. Rev. C 62, 042801(R) (2000).10-2 10-1 100 101 102 103 104 10510-5

10-4

10-3

10-2

10-1

Cros

s Se

ctio

n [b

arn]

Energy [eV]

ENDF/B-VII.0 JENDL-3.3 ENDF/B-VI.8 Gledenov et. al. (2000) This work E. Cheifetz et. al. (1962) This work (extrapolated)

147Sm(n,a)


Measurement of (n,a) cross section for 149Sm

This is the only measured data for this reaction

Used 7.99mg 149Sm (98.03% enriched Sm)

The data are in reasonable agreement with the ENDF/B-7.0 estimate

Extrapolation of the thermal value is in better agreement with the Beg et al. (1965) measurement10

-2 10-1 100 101 102 103 104 10510-6

10-5

10-4

10-3

10-2

10-1

Cros

s Se

ctio

n [b

arn]

Energy [eV]

ENDF/B-VII JENDL-3.3 This work Yu. Andzheevskiy et. al. 1981 K. Beg et. al. 1965 E. Cheifetz et. al. 1962 This work (Extrapolated) Andzheevski 1988 Popov 1980

149Sm(n,a)


Some Recent Measurements Fission

C. Romano, Y. Danon, R. Block, J. Thompson, E. Blain, E. Bond, Fission Fragment Mass And Energy Distributions As A Function of Neutron Energy Measured In A Lead Slowing Down Spectrometer, Phys. Rev. C 81, 014607 (2010)

Mo Analysis in Progress G. Leinweber, D.P. Barry, J.A. Burke(ret.), N.J. Drindak, R.C. Block, Y. Danon, B.E. Moretti, Measurements of elemental molybdenum and resonance parameter analysis,

International Conference on Nuclear Data for Science and Technology (ND2007), April 22-27, Nice, France, (2007) G Leinweber, DP Barry, JA Burke, NJ Drindak, RC Block, Y Danon, BE Moretti, Resonance Parameters and Their Uncertainties Derived from Epithermal Neutron Capture

and Transmission Measurements of Elemental Molybdenum, Nuclear Science And Engineering, 164, 287-303, (2010). C & Be

Y. Danon, R.C. Block, M. Rapp, F. Saglime, D.P. Barry, N.J. Drindak, J. Hool, G. Leinweber, High-Accuracy Filtered Neutron Beam and High-Energy Transmission Measurements at the Gaerttner Laboratory, submitted to the International Conference on Nuclear Data for Science and Technology, April 22-27 2007, Nice, France

Y. Danon , R. C. Block, M. J. Rapp, and F. J. Saglime, G. Leinweber, D. P. Barry, N. J. Drindak and J. G. Hoole, Beryllium and Graphite High Accuracy Total Cross-Section Measurements in the Energy Range from 24 keV to 900 keV, Nuclear Science And Engineering, 161, 321330, (2009)

Sm S. Wang, M. Lubert, Y. Danon, N. C. Francis, R. C. Block, F. Becvar, M. Krticka, The RPI multiplicity detector response to g -ray cascades following neutron capture in 149Sm and 150Sm, NIM A

513/3 pp. 585-595, (2003) Leinweber, G., Burke, J.A., Knox, H.D., Drindak, N.J., Mesh, D.W., Haines, W.T., Ballard, R.V., Block, R.C., Slovacek, R.E., Werner, C.J., Trbovich, M.J. Barry, D.P. and Sato, T., Neutron Capture and

Transmission Measurements and Resonance Parameter Analysis of Samarium, Nuclear Science and Engineering, 142, 1-21, 2002 Gd using diluted samples enriched with 155 and 157.

G. Leinweber, D.P. Barry, M.J. Trobovich, J.A. Burke, N.J. Drindak, , HD Knox, RV Ballad, R.C. Block, Y. Danon, L.I. Severnyak, Neutron Capture and Total Cross-Section Measurements and Resonance Parameters of Gadolinium,. Nuc. Sci Eng. 154, 261-279 (2006).

Nb N.J. Drindak, J.A. Burke, G. Leinweber, J.A. Helm, J.G. Hoole, R.C. Block, Y. Danon, R.E. Slovacek, B.E. Moretti, C.J. Werner, M.E. Overberg, S.A. Kolda, M.J. Trobovich, D.P. Barry, Neutron Capture

and Transmission Measurements and Resonance Parameter Analysis of Niobium, Nuc. Sci Eng. 154, 294-301 (2006).

Nd D. P. Barry, M. J. Trbovich, Y. Danon, R. C. Block, R. E. Slovacek, G. Leinweber, J. A. Burke, N. J. Drindak, Neutron Capture and Total Cross-Section Measurements and Resonance Parameter

Analysis of Neodymium from 1.0 eV TO 500 eV, The Tenth International Conference on Radiation Shielding and Radiation Protection & Shielding Topical (ICRS10 / RPS-2004), Madeira, Portugal, May 9-14, (2004)

D. P. Barry, M. J. Trbovich, Y. Danon, R. C. Block, R. E. Slovacek, G. Leinweber, J. A. Burke, N. J. Drindak, Neutron Transmission and Capture Measurements and Resonance Parameter Analysis of Neodymium From 1.0 eV To 500 eV. Nuclear Science And Engineering: 153, 82, (2006)

Hf M. J. Trbovich, D. P. Barry, R.E. Slovacek, Y. Danon, R. C. Block, N. C. Francis, M Lubert, J. A. Burke, N. J. Drindak, G. Leinweber, R. Ballad, Hafnium Resonance Parameter Analysis Using Neutron

Capture and Transmission Experiments Nuclear Science And Engineering, 161, 303320, (2009). Cs Including CsF crystals and Cs2Co3 diluted sample Cd Analysis in progress 236U Analysis in progress

Thermal and epithermal Transmission with 89.2% enriched samples and capture with a ~50 mg sample of 99.8% enrichment were completed. Rh Analysis in progress Re Analysis in progress Gd-155,156,157,158,160 Capture analysis in progress Dy-161,162,163,164 Capture analysis in progress. Eu-nat, Eu-153 Capture and Transmission analysis in progress

The Nuclear Data Program at Rensselaer CollaborationOutlineThe RPI LINAC FacilityThe RPI LINAC FacilityNeutron Producing TargetsDetectorsCurrent ActivityResonance Region DetectorsTransmission ExperimentCapture Experiments Resonance Cross Section Measurements and Data AnalysisElemental MolybdenumElemental Molybdenum 120 eV - 145 eVGd Transmission and CaptureNew Gd Resonances155,157Gd Thermal Region - Separated IsotopesNew 155,156,157,158,160Gd Capture MeasurementsThermal Total Cross Section of Natural Cd - IThermal Total Cross Section of Natural Cd - IIEu Transmission compared to ENDF/B-7.0High Resolution Transmission DetectorSlide Number 23Simultaneous Measurement of the Fission And Capture Cross Section of 235UResonance Scattering ExperimentExperimental SetupMeasured DataResults - 238U ScatteringOther Resonances (Back Scattering)High Energy Transmission Experimental SetupBackground DeterminationGraphite TransmissionResults Carbon Total Cross SectionBeryllium TransmissionBeryllium Total Cross Section (Low Energy)Mo Total Cross SectionMo Total Cross Section Below 1 MeVZr Total Cross Section Measurements (0.5-20 MeV)Ti Total Cross Section Measurements (0.5-20 MeV)Ti Total Cross Section Measurements 0.5-1 MeV energy regionTantalumTALYS vs EMPIREFast Neutron Scattering Detector ArrayScattering Detection System:Experimental SetupGamma Background Reduction by Pulse Shape AnalysisScattering Setup IllustrationCarbon Experimental Results (Validation)Beryllium Experimental ResultsMolybdenum Experimental ResultsHigh Precision Cross Section Measurements Using Filtered BeamsMotivation - Beryllium Total Cross SectionIron Filter Experimental SetupNatural Iron FilterExperimental DataResults - GraphiteBe TransmissionResults - BerylliumLead Slowing Down SpectrometerLead Slowing-down Spectrometer at RPIFission Fragment KinematicsSETUPResults Fission Fragment Mass distribution En

y. danon rensselaer polytechnic institute, troy, …€¢ z. blain • r. bahran • m. rapp ......

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