Neutron Physics at NIST

M. Arif

8th UCN WorkshopSt. Petersburg – Moscow, Russia

June 11-21, 2011

NCNR Guide Hall20 MW Reactor

Neutron Physics at the NCNR

Beam Flux

n cm-2 s-1Peak

WavelengthAvailable Beam

SizeDistance Beam type Monochromator

Polarizer/Analyzer

Filter

NG-6 2.30E+09 0.50 nm 6 cm x 7.5 cm 0.1 m Polychromatic N/A SM, 3He Bi/Be (77 K)NG-6U 4.70E+06 0.89 nm 7 cm (dia.) 2 m Monochromatic PG (I) N/A N/ANG-6M 6.50E+05 0.50 nm 1 cm (dia.) 3m Monochromatic PG SM, 3He Be (77 K)NG-6A 5.00E+05 0.38 nm 2 cm X 3 cm 4m Monochromatic Si (P) SM, 3He N/ANG-7 2.00E+05 0.27 nm 2 cm X 4 cm 8m Monochromatic PG (D) SM, 3He N/ABT-2 3.00E+07 0.18 nm 26 cm (dia.) 5m Polychromatic N/A SM, 3He Bi (77 K)TC- 1, 2,3 1.00E+08 0.18 nm 3 cm (dia.) 2m Polychromatic N/A N/A Be (293 K)

NG-6A

NG-7BT-2

TC-1,2,3

NG-6 Experiments

Beam Neutron Lifetime Testing

Time Reversal Asymmetry (emiT) Testing

Parity Violating Spin Roation in Helium I

Time Reversal Asymmetry (emiT) I

Beam Neutron lifetime

Time Reversal Asymmetry(emiT) II

Radiative Decay of Neutrons (RDK) I

Parity Violating Spin Roation in Helium I

Radiative Decay of Neutrons (RDK) II

Electron- Antineutron Correlation (aCORN)

NG-6U Experiments

Neutron Lifetime Measurement with UCN

Mark I (2000)

Demonstrated the technique of 3-D magnetic trapping by confining approximately 480 neutrons per loading cycle.

Mark II (2004)

Upgraded magnet.

Increased the number of trapped neutrons to approximately 1,600 Successful proof-of-principle lifetime measurement.

Explored various systematic effects, including marginally trapping.

Mark III (2004 - present)

Completely rebuilt the apparatus incorporating a new magnetic trap that has allowed us to trap more than 10,000 neutrons per loading cycle.Taken initial lifetime data.

Initial analysis is underway.

NG-6M Experiments

Absolute Neutron Fluence Measurement

Neutron fluence is measured by counting

gamma-rays from the reaction n+10B 4He+7Li + (478KeV) with a calibrated gamma

detector and neutron calorimeter.

Polarized 3-He Neutron Spin Analyzers

A Spin Exchange Optical Pumping produces dense

samples of hyper-polarized 3He gas that can be used

to spin analyze neutron beams. This compact system

can be located near an instrument or be mounted in a

neutron beam to provide a constant 3He polarization

and was used in the initial Schwinger scattering

experiment.

NG-6A Experiments

Neutron Schwinger Scattering Experiment

Schwinger scattering is caused by the interaction between the neutron magnetic dipole moment (MDM) and the atomic electric field in the silicon crystal. The atomic electric field rotates the neutron polarization by a very small angle (about 3.210-4

radians). This rotation is magnified by successive (220) Bragg reflections down a narrow slot cut from perfect silicon.

Far Ultraviolet Neutron Detector

This detector, based charged-particle-producing neutron absorption reactions with,3He, 10B, or 6Li, measures far ultraviolet light produced by noble gas excimers instead of amplifying and collecting charge. This new technique may be able to circumvent limitations of 3He proportional tubes, especially the lack of 3He, while preserving their advantages over other techniques. (Patent, R&D 100)

NG -7 Experiments

Neutron Interferometer

Precision Scattering Length Measurement: Silicon

Mass Density of Thin Polymer Films

Search for Quantum Entanglement in Liquid H2O-D2O Mixtures

Demonstration 4π Periodicity of Neutron wave function

Precision Scattering Length Measurement: H and D

Precision Scattering Length Measurement: 3He (spin-independent)

Neutron Charge Radius (Continuing)

Reciprocal Space Neutron Imaging

Vertical Coherence Length in Neutron Interferometry

Precision Scattering Length Measurement: 3He (spin -dependent)

Decoherence Free Neutron Interferometer (QIP)

Precision Scattering Length Measurement: 4He

Magnetic Film characterizations (QIP)

Neutron Interferometeric Study QIP

noayesa ny Will you marry me?

n

y

nny

yny

PC

CP

aaa

aaa *

*

*2

2

Quantum Information

Classical Information

n

y

P

P

0

0

00

011yes

10

000no

Bit or Qubit?

01in

in

10

0ˆie

321123

ˆˆˆˆˆˆˆˆ BBBBBB inout

outO PTrI ˆ

outH PTrI ˆ

1B̂ 2B̂ 3B̂

Adding spin to Neutron Interferometer makes it operate like a 2 qubit Quantum Information Processor and may allow study of the all important quantum decoherence phenomena in QIP.

In neutron interferometry we can detect individual events and the time scale of the evolution is such that we can modify the experiment between counts. This is different from other method such as NMR where it possible to influence a classical ensemble only.

’2 qubit’ quantum computer’

Quantum Gates In Neutron Interferometry

BT-2 Experiments

Neutron Imaging

Fuel Cell

Hydrogen Storage Devices

Li-Ion Batteries

Membranes

Geology and Archeology

Very high resolution detector development

Additional Cold Neutron Phase Imaging Facility (2013)

Large user base from government, industry, and academia

Other Programs

Neutron Instrument Calibrations

Neutron Source Calibrations

Neutron Detector Developments

Neutron Standards Development

Homeland Security Related Research

Neutron Cross-sections Standards

Fast Neutron Measurement for

DUSEL

Additional Facilities

Laser Labs for He-3 Cell Fabrication252Cf Facility

D-T and D-D Neutron Generators

Mn bath neutron Source Calibration Facility

Low Scatter Neutron Dosimeter Calibration Facility

December 31, 2012

Physics

Physics

Physics

NG-C ready

NG-7A Beam-line ready

Second interferometer station

Second cold source at BT-9

NG-7A

NG-C

New Guide Hall Section

December 31, 2014

Physics

Physics

Physics

LD2 cold source installation complete

Neutron Physics on NG-6 completes move to NG-3. NG-3 has optical filter.

Upgrade NG-3 guide?

NG-C Experiment should be in progress

NG-C

NG-3

–2015?Liquid D2 Cold Source (2014)

New cold Source becomes operational at the end of 2014

NG-C Guide

Local shutter is located in the middle section of the guide

Total Length: 57.49 m

Radius : 933 m

NG-C becomes operational by the end of 2012

0

2E+10

4E+10

6E+10

8E+10

1E+11

1.2E+11

0 5 10 15 20 25 30

Neu

tro

ns

[n.s

-1.A

-1]

Wavelength [A]

NG-C LD2 Cold Source (2014)

NG-C LH2 Cold Source (2012)

NG-6 LH2 Cold Source

0

1E+11

2E+11

3E+11

4E+11

5E+11

6E+11

0 5 10 15 20 25 30

Inte

gra

ted

Neu

tron

s [n

.s-1

]

Integration Range [A]

NG-C Neutron Counts

0.0E+00

4.0E+09

8.0E+09

1.2E+10

1.6E+10

2.0E+10

0 5 10 15 20 25 30

Inte

gra

ted

Ca

ptu

re F

lux [

n.c

m-2

.s-1

]

Integration Range [A]

0.0E+00

5.0E+08

1.0E+09

1.5E+09

2.0E+09

2.5E+09

3.0E+09

0 5 10 15 20 25 30

Ca

ptu

re F

lux [

n.c

m-2

.s-1

.A-1

]

Wavelength [A]

NGC LD2 Cold Source

(2014)

NGC LH2 Cold Source

(2012)

0

50

100

150

200

250

300

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Facility Operating Days

IPNS Lujan HFIR NCNR SNS ILL

A. 3He Neutron Polarizer and Analyzer

Polarized 3He program begun 1993. Spin-off NCNR

program for users begun 2006. Neutron physics

applications include NPDg, interferometry,

polarimetry, and axion limits. Recent work is relevant

to operation in high flux beams.

B. Super Mirror Neutron Polarizer and Analyzers

C. Helium Recovery and Re-liquefaction System

Will supply all of NIST's liquid helium needs.

Initially hooked up to recover 60% of NIST use

by recovering from two buildings (235, 223)

Will produce 150,000 liters of LHe annually.

Can be expanded to 250,000 liters/yr production

easily

Primary reason for system is to insulate NIST

program from helium supply interruptions

Groundbreaking May, 2011. Project completion

June, 2012 (commissioned and as-built drawings

submitted)

Experiment Support Infrastructure

New Guide Hall With Instruments

New Guide Hall Photos

Ph.D. Students (40)Jonathan Richardson Harvard University T.E. Chupp 1993

Eric Wasserman Harvard University T.E. Chupp 1994

Klaus Raum University of Innsbruck, Austria A. Zeilinger 1995

Diane Markoff University of Washington B. Heckel 1997

Shenq-Rong Hwang University of Michigan T.E. Chupp 1998

Peter Fischer Munich Technical University, Germany F. Mezei 1998

Laura Lising University of California–Berkeley S.J. Freedman 1999

Annette LaCroix University of Innsbruck, Austria A. Zeilinger 1999

Clinton Brome Harvard University J.M. Doyle 1999

Zema Chowdhuri Indiana University W.M. Snow 2000

Ken Litrell University of Missouri S.A.Werner 2000

Daniel McKinsey Harvard University J.M. Doyle 2002

Carlo Mattoni Harvard University J.M. Doyle 2002

Pieter Mumm University of Washington J.F. Wilkerson 2003

Hartmut Lemmel Atom Institute, Austria H. Rauch 2003

Sergei Dzhosyuk Harvard University J.M. Doyle 2004

Keary Schoen University of Missouri S.A. Werner 2004

Greg Hansen Indiana University W.M. Snow 2004

Liang Yang Harvard University J.M. Doyle 2006

Dmitry Pushin Massachusetts Institute of Technology D. Cory 2006

Chris Bass Indiana University W.M. Snow 2008

Robert Cooper University of Michigan T.E. Chupp 2008

Bob Trull Tulane University F.E. Wietfeldt 2008

Venera Zhumabekova Kazakh National N. Takibayev 2008

Mike Huber Tulane University F.E. Wietfeldt 2009

Da Luo Indiana University W.M. Snow 2009

George Noid Indiana University E. Stephenson 2010

Chris O'Shaughnessy North Carolina State University P. Huffman 2010

Kangfei Gan George Washington University A. Opper 2011

Carl Schelhammer North Carolina State University P. Huffman Current

Andrew Yue University of Tennessee G. Greene Current

Ben O’Neill Arizona State R. Alarcon Current

Tom Langford University of Maryland E. Beise Current

Matt Bales University of Michigan T. E. Chupp Current

Mohamed AbuTaleb Massachusetts Institute of Technology David Cory Current

Taufique Hassan Tulane F. Wietfeltd Current

Chandra Shahi Tulane F. Wietfeldt Current

Typically about a total of thirty five (35) permanent staff, resident guest researchers, post docs, and students at any given time

Responsible for 9 neutron beam-lines (3 more after the upgrade)

Extensive outside collaborations

We are…

There goes the bell…My time is up!

THANK YOU