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Displaying 1401 - 1425 of 2503

Precision measurement of the speed of propagation of neutrinos using the MINOS detectors

September 17, 2015
Author(s)
Stefania Romisch, P Adamson, I Anghel, Neil Ashby, A Aurisano, G. Barr, M. Bishai, A. Blake, C. M. Castromonte, S. Childress, M. Christensen, J. A. Coelho, L. Corwin, D. Cronin-Hennessy, J. K. de Jong, A. V. Devan, N. E. Devenish, M. V. Diwan, C. O. Escobar, J. J. Evans, E. Falk, G. J. Feldman, Blair Fonville, M. V. Frohne, H. R. Gallagher, R. A. Gomes, M. C. Goodman, P. Gouffon, N. Graf, R. Gran, K. Grzelak, A. Habig, S. R. Hahn, J. Hartnell, R. Hatcher, Jonathan Hirschauer, A. Holin, J. Huang, J. Hylen, G M. Irwin, Z. isvan, C. James, Steven R. Jefferts, D. Jensen, T. Kafka, S. M. Kasahara, G. Koizumi, M. Kordosky, A. Kreymer, K. Lang, J. Ling, P. J. Litchfield, P. Lucas, W. A. Mann, M. L. Marshak, Demetrios Matsakis, N. Mayer, Angela Mckinley, C. McGivern, M. M. Medeiros, R. Mehdiyev, J Meier, M. D. Messier, W. H. Miller, S. R. Mishra, Stephen Mitchell, S. Moed Sher, C. D. Moore, L. Mualem, J. A. Musser, D. Naples, J. K. Nelson, H. Newman, R. J. Nichol, J. A. Nowak, J. C. O'Conner, M. Orchanian, R. B. Pahlka, J. Paley, Thomas E. Parker, R. B. Patterson, G. Pawloski, A. Perch, S. Phan-Budd, R. K. Plunkett, N. Poonthattatil, Ed Powers, X. Qiu, A. Radovick, B. Rebel, K. Ridl, C. Rosenfeld, H. A. Rubin, M. C. Sanchez, J. Schneps, A. Schreckenberger, P. Schreiner, R. Sharma, A, Sousa, N. Tagg, R, L. Talaga, J. Thomas, M. A. Thomson, X. Tian, A. Timmons, S. C. Tognini, R. Toner, D. Torretta, J. Urheim, P. Vahle, B. Viren, A. Weber, R. C. Webb, C. White, L. Whitehead, L. H. Whitehead, S. G. Wojcicki, J. Wright, Victor S. Zhang, R. Zwaska
We report a two-detector measurement of the propagation speed of neutrinos over a baseline of 734 km. The measurement was made with the NuMI beam at Fermilab between the near and far MINOS detectors. The fractional difference between the neutrino speed and

When does a branched polymer becomes a particle?

September 17, 2015
Author(s)
Alexandros Chremos, Jack F. Douglas
Melts with topologically distinct molecular structures are investigated by molecular dynamics simulation. We determine the mean polymer size and shape, and glass transition temperature for each molecular topology. Both in terms of structure and dynamics

The Osmotic Virial Repersentation of the Free Energy of Polymer Mixing

September 14, 2015
Author(s)
Jack F. Douglas, August W. Bosse
In this Letter we derive a new representation of the free energy of polymer mixing. We begin with a Flory-Huggins-like free energy of mixing, and assume that the excess free energy of mixing exhibits an arbitrary dependence on the blend composition that

Report for Dedicated JPSS VIIRS Ocean Color Calibration/Validation Cruise

September 10, 2015
Author(s)
Bettye C. Johnson, Michael Ondrusek, Eric Stengel, Veronica P. Lance, Menghua Wang, Kenneth Voss, Giuseppe Zibordi, Marco Talone, Zhongping Lee, Jianwei Wei, Junfang Lin, Chuanmin Hu, David English, Charles Kovach, Jennifer Cannizzaro, Alex Gilerson, Sam Ahmed, Amir Ibrahim, Ahmed El-Habashi, Robert Foster, Robert Arnone, Ryan Vandermeulen, Sherwin Ladner, Wesley Goode, Joaquim I. Goes, Helga de Rosario Gomes, Kali McKee, Scott Freeman, Aimee Neeley
The purpose of this cruise aboard the NOAA Ship Nancy Foster was to collect in situ optical and ancillary data for validation of JPSS VIIRS satellite ocean color radiometry and derived products [Wang et al., 2013; Wang et al., 2014]. The project interval

Direct Immersion Annealing of Thin Block Copolymer Films

September 9, 2015
Author(s)
Jack F. Douglas, Alamgir Karim, Arvind Arvind Modi1, Sarang Bhaway, Bryan D. Vogt, Abdullah Al-Enizi, Ahmed Elzatahry, Ashutosh Sharma
We demonstrate that direct immersion annealing (DIA) greatly enhances the rate at which block copolymer (BCP) films order into stable morphologies when the BCP films are immersed in carefully selected mixtures of good and marginal solvents that can impart

A detailed comparison of two continuous GPS carrier-phase time transfer techniques

September 8, 2015
Author(s)
Jian Yao, Judah Levine, Skakun Ivan, Zhiheng Jiang
The wide application of GPS carrier-phase (CP) time transfer is limited by the problem of boundary discontinuity (BD). The discontinuity has two categories. One is "day boundary discontinuity," which has been studied extensively and can be solved by a few

Prospects for atomic clocks based on large ion crystals.

September 8, 2015
Author(s)
John J. Bollinger, Kyle Arnold, Elnur Haciyev, Chern Hui Lee, Eduardo Paez, M. D. Barrett
We investigate the feasibility of precision frequency metrology with large ion crystals. For clock candidates with a negative differential static polarisability, we show that micromotion effects should not impede the performance of the clock. Using Lu+ as

SOLAR-WIND ION DRIVEN X-RAY EMISSION FROM COMETARY AND PLANETARY ATMOSPHERES: MEASUREMENTS AND THEORETICAL PREDICTIONS OF CHARGE- EXCHANGE CROSS SECTIONS AND EMISSION SPECTRA FOR O6+ + H2O, CO, CO2, CH4, N2, NO, N2O, AND Ar

August 15, 2015
Author(s)
J. R. Machacek, D. P. Mahapatra, David R. Schultz, Yuri Ralchenko, A. Moradmand, O. E. Ghazaly, A. Chutjian
Relevant to modeling and understanding X-ray emission from cometary and planetary atmospheres, total cross sections for 1.17 and 2.33 keV/u O6+ colliding with H2O, CO, CO2, CH4, N2, NO, N2O, and Ar have been measured for the processes of single, double

Experiments with highly-ionized atoms in unitary Penning traps

August 14, 2015
Author(s)
Shannon Hoogerheide, Aung Naing, Joan M. Dreiling, Samuel Brewer, Nicholas D. Guise, Joseph Tan
Highly-ionized atoms with special properties have been proposed for interesting applications, including potential candidates for a new generation of optical atomic-clocks at the 1 part in 1019 level of precision, quantum-information processing, and tests

Self-referencing a CW laser with efficient nonlinear optics

July 26, 2015
Author(s)
Scott B. Papp, Katja M. Beha, Daniel C. Cole, Pascal P. Del'Haye, Aurelien C. Coillet, Scott A. Diddams
We phase-coherently measure the frequency of continuous-wave (CW) laser light by use of optical-phase modulation and 'f-2f' nonlinear interferometry. Periodic electro-optic modulation (EOM) transforms the CW laser into a continuous train of picosecond

Development of an Ultra-Pure, Carrier-Free 209Po Solution Standard

July 23, 2015
Author(s)
Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
Ultra-pure, carrier-free 209Po solution standards have been prepared and standardized for their massic alpha-particle emission rate. The standards, which will be disseminated by the National Institute of Standards and Technology (NIST) as Standard

Controlling the electronic structure of graphene using surface-adsorbate interactions

July 21, 2015
Author(s)
Piotr Matyba, Adra V. Carr, Cong Chen, David L. Miller, Thomas Orlando, Stefan Mathias, Mark W. Keller, Henry C. Kapteyn, Margaret M. Murnane
Hybridization of atomic orbitals in graphene on Ni(111) opens up a large energy gap of ≈2.8 eV between nonhybridized states at the K point. Here we use alkali-metal adsorbate to reduce and even eliminate this energy gap, and also identify a new mechanism

Compact X-ray and Extreme-Ultraviolet Light Sources

July 10, 2015
Author(s)
Lahsen Assoufid, Uwe Arp, Patrick Naulleau, Sandra Biedron , William Graves
Bringing the brightness and power of vast synchrotron and free-electron laser sources to the scale of the lab and clinic marks an important next frontier—and could transform the landscape of X-ray science and technology.

Resonant interaction of trapped cold atoms with a magnetic cantilever tip

June 26, 2015
Author(s)
John E. Kitching, Chris Montoya, Jose Valencia, Andrew A. Geraci, Matt Eardley, John M. Moreland
Magnetic resonance in an ensemble of laser-cooled trapped Rb atoms is excited using a micro cantilever with a magnetic tip. The cantilever is mounted on a multi-layer atom chip designed to capture, cool, and magnetically transport cold atoms. The coupling

A Unifying Framework to Quantify the Effects of Boundary Stiffness, Polymer-Substrate Interactions and Substrate Roughness on the Dynamics of Thin Supported Polymer Films

June 21, 2015
Author(s)
Jack F. Douglas, Paul Hanakata, Francis W. Starr, Beatriz Betancourt
Changes in the dynamics of supported polymer films in comparison to bulk materials involve a complex convolution of effects, such as boundary thermodynamic interactions, boundary roughness and compliance, in addition to finite film thickness. We consider

CALIBRATION AND CHARACTERIZATION OF A SEAPRISM RADIOMETER FOR AERONET-OC

June 19, 2015
Author(s)
Bettye C. Johnson, Steven W. Brown, John T. Woodward IV, Keith R. Lykke, Giuseppe Zibordi
The global Aerosol Robotic Network for Ocean Color (AERONET-OC) program utilizes AERONET CE-318 sun photometers (termed “SeaPRISMs”) modified for in-air observations of ocean waters situated on oil drilling rigs, off-shore lighthouses, or other platforms

Resolving the vacuum fluctuations of an optomechanical system using an artificial atom

June 15, 2015
Author(s)
Florent Q. Lecocq, John D. Teufel, Jose A. Aumentado, Raymond W. Simmonds
Heisenberg's uncertainty principle results in one of the strangest quantum behaviours: a mechanical oscillator can never truly be at rest. Even at a temperature of absolute zero, its position and momentum are still subject to quantum fluctuations. However

Dedicated NOAA/JPSS VIIRS Ocean Color Calibration/Validation Cruise

June 12, 2015
Author(s)
Bettye C. Johnson, Michael Ondrusek, Eric Stengel, Veronica P. Lance, Menghua Wang, Kenneth Voss, Giuseppe Zibordi, Marko Talone, Zhongping Lee, Jianwei Wei, Junfang Lin, Chuanmin Hu, David English, Charles Kovach, Jennifer Cannizzaro, Alex Gilerson, Sam Ahmed, Ahmed El-Habashi, Robert Foster, Robert Arnone, Ryan Vandermeulen, Sherwin Ladner, Wesley Goode, Joaquim I. Goes, Helga de Rosario Gomes, Alex Chekalyuk, Kali McKee, Scott Freeman, Aimee Neeley, Amir Ibrahim
The NOAA/STAR Ocean Color team is focused on “end-to-end” production of ocean color satellite products. In situ validation of satellite data is essential to producing the high-quality products required and expected by the international ocean color remote
Displaying 1401 - 1425 of 2503
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