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The Upscattering Of Ultracold Neutrons From The Polymer (C6h12)N, Eduard I. Sharapov, Christopher L. Morris, Mark Makela, Andy Saunders, Evan R. Adamek, Leah J. Broussard, Chris B. Cude-Woods, Deion E. Fellers, Peter Geltenbort, Monika Hartl, Siraj I. Hasan, Kevin P. Hickerson, Gary E. Hogan, Anthony T. Holley, C. M. Lavelle, Chen-Yu Liu, Michael P. Mendenhall, Jose Ortiz, Robert W. Pattie, David G. Phillips, John Ramsey, Daniel J. Salvat, Susan J. Seestrom, Erik Shaw, Sky Sjue, Walter E. Sondheim, Brittany Vorndick, Zhehui Wang, Tanner L. Womack, Andrew R. Young, B. A. Zeck

Robert W. Pattie Jr.

It is generally accepted that the main cause of ultracold neutron (UCN) losses in storage traps is upscattering to the thermal energy range by hydrogen adsorbed on the surface of the trap walls. However, the data on which this conclusion is based are poor and contradictory. Here we report a measurement, performed at the Los Alamos National Laboratory UCN source, of the average energy of the flux of upscattered neutrons after the interaction of UCN with hydrogen bound in the semicrystalline polymer PMP (trade name TPX), [C6H12]n. Our analysis, performed with the mcnp code which applies …

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Limits On Tensor Coupling From Neutron Β Decay, Robert W. Pattie, Kevin P. Hickerson, Andrew R. Young

Robert W. Pattie Jr.

Limits on the tensor couplings generating a Fierz interference term b in mixed Gamow-Teller Fermi decays can be derived by combining data from measurements of angular correlation parameters in neutron decay, the neutron lifetime, and GV=GFVud as extracted from measurements of the Ftvalues from the 0+→0+ superallowed decay data set. These limits are derived by comparing the neutron β-decay rate as predicted in the standard model with the measured decay rate while allowing for the existence of beyond the standard model (BSM) couplings. We analyze limits derived from …

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Measurements Of Ultracold Neutron Upscattering And Absorption In Polyethylene And Vanadium, Eduard I. Sharapov, Charles L. Morris, Mark Makela, Andy Saunders, Evan R. Adamek, Yelena Bagdasarova, Leah J. Broussard, Chris Cude-Woods, Deon E. Fellers, Peter Geltenbort, Siraj I. Hasan, Kevin P. Hickerson, Gary Hogan, Anthony T. Holley, Chen-Yu Liu, Michael P. Mendenhall, Jose Ortiz, Robert W. Pattie Jr., David G. Phillips, John Ramsey, D. J. Salvat, Susan J. Seestrom, E. Shaw, Sky Sjue, Walter E. Sondheim, Brittany Vorndick, Zhehui Wang, Tanner L. Womack, Andrew R. Young, B. A. Zeck

Robert W. Pattie Jr.

The study of neutron cross sections for elements used as efficient “absorbers” of ultracold neutrons (UCN) is crucial for many precision experiments in nuclear and particle physics, cosmology and gravity. In this context, “absorption” includes both the capture and upscattering of neutrons to the energies above the UCN energy region. The available data, especially for hydrogen, do not agree between themselves or with the theory. In this report we describe measurements performed at the Los Alamos National Laboratory UCN facility of the UCN upscattering cross sections for vanadium and for hydrogen in CH2 using simultaneous measurements of the radiative …

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Project X: Physics Opportunities, Andreas S. Kronfeld, Robert S. Tschirhart, Usama Al-Binni, Wolfgang Altmannshofer, Charles Ankenbrandt, Kaladi Babu, Sunanda Banerjee, Matthew Bass, Brian Batell, David V. Baxter, Zurab Berezhiani, Marc Bergevin, Robert Bernstein, Sudeb Bhattacharya, Mary Bishai, Thomas Blum, S. Alex Bogacz, Stephen J. Brice, Joachim Brod, Alan Bross, Michael Buchoff, Thomas W. Burgess, Marcela Carena, Luis A. Castellanos, Subhasis Chattopadhyay, Mu-Chun Chen, Daniel Cherdack, Norman H. Christ, Tim Chupp, Vincenzo Cirigliano, Pilar Coloma, Christopher E. Coppola, Ramanath Cowsik, J. Allen Crabtree, André De Gouvêa, Jean-Pierre Delahaye, Dmitri Denisov, Patrick Deniverville, Ranjan Dharmapalan, Alexander Dolgov, Georgi Dvali, Estia Eichten, Jürgen Engelfried, Phillip D. Ferguson, Tony Gabriel, Avraham Gal, Franz Gallmeier, Kenneth S. Ganezer, Susan Gardner

Robert W. Pattie Jr.

Part 2 of "Project X: Accelerator Reference Design, Physics Opportunities, Broader Impacts". In this Part, we outline the particle-physics program that can be achieved with Project X, a staged superconducting linac for intensity-frontier particle physics. Topics include neutrino physics, kaon physics, muon physics, electric dipole moments, neutron-antineutron oscillations, new light particles, hadron structure, hadron spectroscopy, and lattice-QCD calculations. Part 1 is available as arXiv:1306.5022 [physics.acc-ph] and Part 3 is available as arXiv:1306.5024 [physics.acc-ph].

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Precision Measurement Of The Neutron Beta-Decay Asymmetry, Michael P. Mendenhall, Robert W. Pattie, Yelena Bagdasarova, David B. Berguno, Leah J. Broussard, Richard Carr, Scott Currie, Xinjian Ding, Bradley W. Filippone, Alejandro Garcia, Peter Geltenbort, Kevin P. Hickerson, J. Todd Hoagland, Anthony T. Holley, Ran Hong, Takeyasu M. Ito, Andreas Knecht, Chenyu Liu, J. L. Liu, Mark Makela, Russell R. Mammei, J. W. Martin, Dan Melconian, Spencer D. Moore, Christopher L. Morris, Margaret L. Pitt, Blakely Plaster, John C. Ramsey, Roger Rios, Andy Saunders, Susan J. Seestrom, Eduard I. Sharapov, Walter E. Sondheim, E. Tatar, Robert B. Vogelaar, Brittany Vorndick, Christopher Wrede, Andrew R. Young, B. A. Zeck

Robert W. Pattie Jr.

A new measurement of the neutron β-decay asymmetry A0 has been carried out by the UCNA collaboration using polarized ultracold neutrons (UCN) from the solid deuterium UCN source at the Los Alamos Neutron Science Center (LANSCE). Improvements in the experiment have led to reductions in both statistical and systematic uncertainties leading to A0 = −0.11954(55)stat.(98)syst., corresponding to the ratio of axial-vector to vector coupling λ ≡ gA/gV = −1.2756(30).

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Performance Of The Los Alamos National Laboratory Spallation-Driven Solid-Deuterium Ultra-Cold Neutron Source, Andrew Saunders, Mark Makela, Yelena Bagdasarova, Henning O. Back, J. Boissevain, Leah J. Broussard, Thomas J. Bowles, R. Carr, Scott A. Currie, Bradley Filippone, A. García, Peter Geltenbort, Kevin P. Hickerson, R. E. Hill, J. Todd Hoagland, S. Hoedl, Anthony T. Holley, Gary E. Hogan, Takeyasu M. Ito, Steve Lamoreaux, Chen-Yu Liu, J. Liu, Russell R. Mammei, J. Martin, Dan Melconian, Michael P. Mendenhall, Charles L. Morris, R. N. Mortensen, Robert W. Pattie, Margaret Pitt, Bradley Plaster, John Ramsey, R. Rios, A. Sallaska, Susan J. Seestrom, E. I. Sharapov, Sky Sjue, Walter E. Sondheim, W. Teasdale, Andrew R. Young, Brittany Vorndick, Robert B. Vogelaar, Zhehui Wang, Yanping Xu

Robert W. Pattie Jr.

In this paper, we describe the performance of the Los Alamos spallation-driven solid-deuterium ultracold neutron (UCN) source. Measurements of the cold neutron flux, the very low energy neutron production rate, and the UCN rates and density at the exit from the biological shield are presented and compared to Monte Carlo predictions. The cold neutron rates compare well with predictions from the Monte Carlo code MCNPX and the UCN rates agree with our custom UCN Monte Carlo code. The source is shown to perform as modeled. The maximum delivered UCN density at the exit from the biological shield is 52(9) UCN/cc …

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Robert W. Pattie Jr.

Limits On Tensor Coupling From Neutron Β Decay, Robert W. Pattie, Kevin P. Hickerson, Andrew R. Young

Robert W. Pattie Jr.

Robert W. Pattie Jr.

Robert W. Pattie Jr.

Robert W. Pattie Jr.

Robert W. Pattie Jr.