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Atomic, Molecular and Optical Physics

Selected Works

Measurement

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Full-Text Articles in Physics

Measurement Of The Neutron Lifetime Using A Magneto-Gravitational Trap And In Situ Detection, Robert W. Pattie Jr., Nathan B. Callahan, Chris Cude-Woods, Edith R. Adamek, Leah J. Broussard, Stephen M. Clayton, Scott A. Currie, Eric B. Dees, Xiaoping Ding, Egbert M. Engel, D. E. Fellers, William Fox, Peter Geltenbort, Kevin P. Hickerson, Mark A. Hoffbauer, Anthony T. Holley, A. Komives, Chen Liu, S. W. T. Macdonald, Mark Makela, Christopher L. Morris, Joseph D. Ortiz, John C. Ramsey, Daniel J. Salvat, Alexander Saunders, Susan J. Seestrom, E. I. Sharapov, S. K. Sjue, Zebo Tang, J. Vanderwerp, Bruce Vogelaar, P. L. Walstrom, Zhehui Wang, Wei Wei, H. L. Weaver, Judith W. Wexler, Tanner L. Womack, Andrew R. Young, B. A. Zeck May 2018

Measurement Of The Neutron Lifetime Using A Magneto-Gravitational Trap And In Situ Detection, Robert W. Pattie Jr., Nathan B. Callahan, Chris Cude-Woods, Edith R. Adamek, Leah J. Broussard, Stephen M. Clayton, Scott A. Currie, Eric B. Dees, Xiaoping Ding, Egbert M. Engel, D. E. Fellers, William Fox, Peter Geltenbort, Kevin P. Hickerson, Mark A. Hoffbauer, Anthony T. Holley, A. Komives, Chen Liu, S. W. T. Macdonald, Mark Makela, Christopher L. Morris, Joseph D. Ortiz, John C. Ramsey, Daniel J. Salvat, Alexander Saunders, Susan J. Seestrom, E. I. Sharapov, S. K. Sjue, Zebo Tang, J. Vanderwerp, Bruce Vogelaar, P. L. Walstrom, Zhehui Wang, Wei Wei, H. L. Weaver, Judith W. Wexler, Tanner L. Womack, Andrew R. Young, B. A. Zeck

Robert W. Pattie Jr.

The precise value of the mean neutron lifetime, tn, plays an important role in nuclear and particle physics and cosmology. It is used to predict the ratio of protons to helium atoms in the primordial universe and to search for physics beyond the Standard Model of particle physics. We eliminated loss mechanisms present in previous trap experiments by levitating polarized ultracold neutrons above the surface of an asymmetric storage trap using a repulsive magnetic field gradient so that the stored neutrons do not interact with material trap walls. As a result of this approach and the use of an in …

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Measurement Of Spin-Flip Probabilities For Ultracold Neutrons Interacting With Nickel Phosphorus Coated Surfaces, Zhaowen Tang, Evan Robert Adamek, Aaron Brandt, Nathan Brannan Callahan, Steven M. Clayton, Scott Allister Currie, Takeyasu M. Ito, Mark F. Makela, Yasuhiro Masuda, Christopher L. Morris, Robert Wayne Pattie, John Clinton Ramsey, Daniel J. Salvat, Daniel J. Salvat, Alexander Saunders, Albert R. Young Aug 2016

Measurement Of Spin-Flip Probabilities For Ultracold Neutrons Interacting With Nickel Phosphorus Coated Surfaces, Zhaowen Tang, Evan Robert Adamek, Aaron Brandt, Nathan Brannan Callahan, Steven M. Clayton, Scott Allister Currie, Takeyasu M. Ito, Mark F. Makela, Yasuhiro Masuda, Christopher L. Morris, Robert Wayne Pattie, John Clinton Ramsey, Daniel J. Salvat, Daniel J. Salvat, Alexander Saunders, Albert R. Young

Robert W. Pattie Jr.

We report a measurement of the spin-flip probabilities for ultracold neutrons interacting with surfaces coated with nickel phosphorus. For 50 μm thick nickel phosphorus coated on stainless steel, the spin-flip probability per bounce was found to be βNiPonSS=(3.3−5.6+1.8)×10−6. For 50 μm thick nickel phosphorus coated on aluminum, the spin-flip probability per bounce was found to be βNiPonAl=(3.6−5.9+2.1)×10−6. For the copper guide used as reference, the spin flip probability per bounce was found to be βCu=(6.7−2.5+5.0)×10−6. The results on the nickel phosphorus-coated surfaces may be interpreted as upper limits, yielding βNiPonSS<6.2×10−6 (90% C.L.) and βNiPonAl<7.0×10−6 (90% C.L.) for 50 μm thick …

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Superlattice Ultrasonic Generation, Thomas E. Wilson, M. Oehme, E. Kasper, H-J. L. Gossmann Feb 2014

Superlattice Ultrasonic Generation, Thomas E. Wilson, M. Oehme, E. Kasper, H-J. L. Gossmann

Thomas E. Wilson

We report the first experimental evidence for the resonant excitation of coherent high-frequency acoustic phonons in semiconducting doping superstructures by far-infrared laser radiation. After a grating-coupled delta-doped silicon doping superlattice is illuminated with ~1 kW/mm2 nanosecond-pulsed 246 GHz laser radiation, a delayed nanosecond pulse is detected by a superconducting bolometer at a time corresponding to the appropriate time-of-flight for ballistic longitudinal acoustic phonons across the (100) silicon substrate. The absorbed phonon power density in the microbolometer is observed to be ~10 μW/mm2, in agreement with theory. The phonon pulse duration also matches the laser pulse duration. The absence of any …

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Measurement Of The Neutron -Asymmetry Parameter A0 With Ultracold Neutrons, Bradley Plaster, R. Rios, Thomas J. Bowles, Leah J. Broussard, Richard Carr, Steven Clayton, Scott Currie, Bradley W. Filippone, Peter Geltenbort, Kevin P. Hickerson, J. Todd Hoagland, Gary E. Hogan, B. Hona, Anthoney T. Holley, Takeyasu M. Ito, Chenyu Liu, Jingyang Liu, Mark Makela, J. W. Martin, Daniel Melconian, Michael P. Mendenhall, Charles L. Morris, R. Mortensen, Robert W. Pattie, Margaret L. Pitt, John C. Ramsey, R. Russell, Andy Saunders, R. Schmid, Susan J. Seestrom, Sky Sjue, Walter E. Sondheim, E. Tatar, B. Tipton, Robert B. Vogelaar, Brittany Vorndick, Christopher Wrede, Y. P. Xu, H. Yan, Andrew R. Young, J. Yuan Dec 2011

Measurement Of The Neutron -Asymmetry Parameter A0 With Ultracold Neutrons, Bradley Plaster, R. Rios, Thomas J. Bowles, Leah J. Broussard, Richard Carr, Steven Clayton, Scott Currie, Bradley W. Filippone, Peter Geltenbort, Kevin P. Hickerson, J. Todd Hoagland, Gary E. Hogan, B. Hona, Anthoney T. Holley, Takeyasu M. Ito, Chenyu Liu, Jingyang Liu, Mark Makela, J. W. Martin, Daniel Melconian, Michael P. Mendenhall, Charles L. Morris, R. Mortensen, Robert W. Pattie, Margaret L. Pitt, John C. Ramsey, R. Russell, Andy Saunders, R. Schmid, Susan J. Seestrom, Sky Sjue, Walter E. Sondheim, E. Tatar, B. Tipton, Robert B. Vogelaar, Brittany Vorndick, Christopher Wrede, Y. P. Xu, H. Yan, Andrew R. Young, J. Yuan

Robert W. Pattie Jr.

We present a detailed report of a measurement of the neutron β-asymmetry parameter A0, the parity-violating angular correlation between the neutron spin and the decay electron momentum, performed with polarized ultracold neutrons (UCN). UCN were extracted from a pulsed spallation solid deuterium source and polarized via transport through a 7-T magnetic field. The polarized UCN were then transported through an adiabatic-fast-passage spin-flipper field region, prior to storage in a cylindrical decay volume situated within a 1-T 2 × 2π solenoidal spectrometer. The asymmetry was extracted from measurements of the decay electrons in multiwire proportional chamber and plastic scintillator detector packages …

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