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Full-Text Articles in Physics
Observation Of The 1s–2p Lyman-Α Transition In Antihydrogen, M. Ahmadi, B. X.R. Alves, C. J. Baker, W. Bertsche, A. Capra, C. Carruth, C. L. Cesar, M. Charlton, S. Cohen, R. Collister, S. Eriksson, A. Evans, N. Evetts, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, J. S. Hangst, W. N. Hardy, M. E. Hayden, E. D. Hunter, C. A. Isaac, M. A. Johnson, J. M. Jones, S. A. Jones, S. Jonsell, A. Khramov, P. Knapp, L. Kurchaninov, N. Madsen, D. Maxwell, J. T. K. Mckenna, S. Menary, J. M. Michan, T. Momose, J. J. Munich, K. Olchanski, A. Olin, P. Pusa, C. O. Rasmussen, F. Robicheaux, R. L. Sacramento, M. Sameed, E. Sarid, D. M. Silveira, D, M. Starko, G. Stutter, C. So, Timothy Tharp, R. I. Thompson, D. P. Van Der Werf, J. S. Wurtele
Observation Of The 1s–2p Lyman-Α Transition In Antihydrogen, M. Ahmadi, B. X.R. Alves, C. J. Baker, W. Bertsche, A. Capra, C. Carruth, C. L. Cesar, M. Charlton, S. Cohen, R. Collister, S. Eriksson, A. Evans, N. Evetts, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, J. S. Hangst, W. N. Hardy, M. E. Hayden, E. D. Hunter, C. A. Isaac, M. A. Johnson, J. M. Jones, S. A. Jones, S. Jonsell, A. Khramov, P. Knapp, L. Kurchaninov, N. Madsen, D. Maxwell, J. T. K. Mckenna, S. Menary, J. M. Michan, T. Momose, J. J. Munich, K. Olchanski, A. Olin, P. Pusa, C. O. Rasmussen, F. Robicheaux, R. L. Sacramento, M. Sameed, E. Sarid, D. M. Silveira, D, M. Starko, G. Stutter, C. So, Timothy Tharp, R. I. Thompson, D. P. Van Der Werf, J. S. Wurtele
Physics Faculty Research and Publications
In 1906, Theodore Lyman discovered his eponymous series of transitions in the extreme-ultraviolet region of the atomic hydrogen spectrum. The patterns in the hydrogen spectrum helped to establish the emerging theory of quantum mechanics, which we now know governs the world at the atomic scale. Since then, studies involving the Lyman-α line—the 1S–2P transition at a wavelength of 121.6 nanometres—have played an important part in physics and astronomy, as one of the most fundamental atomic transitions in the Universe. For example, this transition has long been used by astronomers studying the intergalactic medium and testing cosmological models via the so-called …
Neutrino Interferometry For High-Precision Tests Of Lorentz Symmetry With Icecube, Karen Andeen, Icecube Collaboration
Neutrino Interferometry For High-Precision Tests Of Lorentz Symmetry With Icecube, Karen Andeen, Icecube Collaboration
Physics Faculty Research and Publications
Lorentz symmetry is a fundamental spacetime symmetry underlying both the standard model of particle physics and general relativity. This symmetry guarantees that physical phenomena are observed to be the same by all inertial observers. However, unified theories, such as string theory, allow for violation of this symmetry by inducing new spacetime structure at the quantum gravity scale. Thus, the discovery of Lorentz symmetry violation could be the first hint of these theories in nature. Here we report the results of the most precise test of spacetime symmetry in the neutrino sector to date. We use high-energy atmospheric neutrinos observed at …
Neutrino Emission From The Direction Of The Blazar Txs 0506+056 Prior To The Icecube-170922a Alert, Icecube Collaboration, Karen Andeen
Neutrino Emission From The Direction Of The Blazar Txs 0506+056 Prior To The Icecube-170922a Alert, Icecube Collaboration, Karen Andeen
Physics Faculty Research and Publications
A high-energy neutrino event detected by IceCube on 22 September 2017 was coincident in direction and time with a gamma-ray flare from the blazar TXS 0506+056. Prompted by this association, we investigated 9.5 years of IceCube neutrino observations to search for excess emission at the position of the blazar. We found an excess of high-energy neutrino events, with respect to atmospheric backgrounds, at that position between September 2014 and March 2015. Allowing for time-variable flux, this constitutes 3.5σ evidence for neutrino emission from the direction of TXS 0506+056, independent of and prior to the 2017 flaring episode. This suggests that …
Multimessenger Observations Of A Flaring Blazar Coincident With High-Energy Neutrino Icecube-170922a, Karen Andeen, Icecube Collaboration, Fermi-Lat, Agile, Asas-Sn, Hawc, H.E.S.S., Integral, Kanata, Kiso, Kapteyn, Liverpool Telescope, Subaru, Swift/Nustar, Veritas, Vla/17b-403
Multimessenger Observations Of A Flaring Blazar Coincident With High-Energy Neutrino Icecube-170922a, Karen Andeen, Icecube Collaboration, Fermi-Lat, Agile, Asas-Sn, Hawc, H.E.S.S., Integral, Kanata, Kiso, Kapteyn, Liverpool Telescope, Subaru, Swift/Nustar, Veritas, Vla/17b-403
Physics Faculty Research and Publications
No abstract provided.
Creating A Ductus From Period Exemplars, Melissa Vigil
Creating A Ductus From Period Exemplars, Melissa Vigil
Physics Faculty Research and Publications
No abstract provided.
A Search For Neutrino Emission From Fast Radio Bursts With Six Years Of Icecube Data, Karen Andeen
A Search For Neutrino Emission From Fast Radio Bursts With Six Years Of Icecube Data, Karen Andeen
Physics Faculty Research and Publications
We present a search for coincidence between IceCube TeV neutrinos and fast radio bursts (FRBs). During the search period from 2010 May 31 to 2016 May 12, a total of 29 FRBs with 13 unique locations have been detected in the whole sky. An unbinned maximum likelihood method was used to search for spatial and temporal coincidence between neutrinos and FRBs in expanding time windows, in both the northern and southern hemispheres. No significant correlation was found in six years of IceCube data. Therefore, we set upper limits on neutrino fluence emitted by FRBs as a function of time window …
Search For Nonstandard Neutrino Interactions With Icecube Deepcore, Karen Andeen, Icecube Collaboration
Search For Nonstandard Neutrino Interactions With Icecube Deepcore, Karen Andeen, Icecube Collaboration
Physics Faculty Research and Publications
As atmospheric neutrinos propagate through the Earth, vacuumlike oscillations are modified by Standard Model neutral- and charged-current interactions with electrons. Theories beyond the Standard Model introduce heavy, TeV-scale bosons that can produce nonstandard neutrino interactions. These additional interactions may modify the Standard Model matter effect producing a measurable deviation from the prediction for atmospheric neutrino oscillations. The result described in this paper constrains nonstandard interaction parameters, building upon a previous analysis of atmospheric muon-neutrino disappearance with three years of IceCube DeepCore data. The best fit for the muon to tau flavor changing term is εμτ=−0.0005, with a 90% …
Characterization Of The 1s–2s Transition In Antihydrogen, M. Ahmadi, B. X.R. Alves, C. J. Baker, W. Bertsche, A. Capra, C. Carruth, C. L. Cesar, M. Charlton, S. Cohen, R. Collister, S. Eriksson, A. Evans, N. Evetts, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, J. S. Hangst, W. N. Hardy, M. E. Hayden, C. A. Isaac, M. A. Johnson, J. M. Jones, S. A. Jones, S. Jonsell, A. Khramov, P. Knapp, L. Kurchaninov, N. Madsen, D. Maxwell, J. T.K. Mckenna, S. Menary, T. Momose, J. J. Munich, K. Olchanski, A. Olin, P. Pusa, C. Ø. Rasmussen, F. Robicheaux, R. L. Sacramento, M. Sameed, E. Sarid, D. M. Silveira, G. Stutter, C. So, Tim Tharp, R. I. Thompson, D. P. Van Der Werf, J. S. Wurtele
Characterization Of The 1s–2s Transition In Antihydrogen, M. Ahmadi, B. X.R. Alves, C. J. Baker, W. Bertsche, A. Capra, C. Carruth, C. L. Cesar, M. Charlton, S. Cohen, R. Collister, S. Eriksson, A. Evans, N. Evetts, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, J. S. Hangst, W. N. Hardy, M. E. Hayden, C. A. Isaac, M. A. Johnson, J. M. Jones, S. A. Jones, S. Jonsell, A. Khramov, P. Knapp, L. Kurchaninov, N. Madsen, D. Maxwell, J. T.K. Mckenna, S. Menary, T. Momose, J. J. Munich, K. Olchanski, A. Olin, P. Pusa, C. Ø. Rasmussen, F. Robicheaux, R. L. Sacramento, M. Sameed, E. Sarid, D. M. Silveira, G. Stutter, C. So, Tim Tharp, R. I. Thompson, D. P. Van Der Werf, J. S. Wurtele
Physics Faculty Research and Publications
In 1928, Dirac published an equation1 that combined quantum mechanics and special relativity. Negative-energy solutions to this equation, rather than being unphysical as initially thought, represented a class of hitherto unobserved and unimagined particles—antimatter. The existence of particles of antimatter was confirmed with the discovery of the positron2 (or anti-electron) by Anderson in 1932, but it is still unknown why matter, rather than antimatter, survived after the Big Bang. As a result, experimental studies of antimatter3,4,5,6,7, including tests of fundamental symmetries such as charge–parity and charge–parity–time, and searches …
How Do We Know What They Used?, Melissa Vigil
How Do We Know What They Used?, Melissa Vigil
Physics Faculty Research and Publications
No abstract provided.
Measurement Of Atmospheric Neutrino Oscillations At 6–56 Gev With Icecube Deepcore, Karen Andeen
Measurement Of Atmospheric Neutrino Oscillations At 6–56 Gev With Icecube Deepcore, Karen Andeen
Physics Faculty Research and Publications
We present a measurement of the atmospheric neutrino oscillation parameters using three years of data from the IceCube Neutrino Observatory. The DeepCore infill array in the center of IceCube enables the detection and reconstruction of neutrinos produced by the interaction of cosmic rays in Earth’s atmosphere at energies as low as ∼5 GeV. That energy threshold permits measurements of muon neutrino disappearance, over a range of baselines up to the diameter of the Earth, probing the same range of L/Eν as long-baseline experiments but with substantially higher-energy neutrinos. This analysis uses neutrinos from the full sky with reconstructed energies …
Disordered Kagomé Spin Ice, Noah Greenberg, Andrew Kunz
Disordered Kagomé Spin Ice, Noah Greenberg, Andrew Kunz
Physics Faculty Research and Publications
Artificial spin ice is made from a large array of patterned magnetic nanoislands designed to mimic naturally occurring spin ice materials. The geometrical arrangement of the kagomé lattice guarantees a frustrated arrangement of the islands’ magnetic moments at each vertex where the three magnetic nanoislands meet. This frustration leads to a highly degenerate ground state which gives rise to a finite (residual) entropy at zero temperature. In this work we use the Monte Carlo simulation to explore the effects of disorder in kagomé spin ice. Disorder is introduced to the system by randomly removing a known percentage of magnetic islands …
Enhanced Control And Reproducibility Of Non-Neutral Plasmas, Timothy Tharp, M. Ahmadi, B. X. R. Alves, C. J. Baker, W. Bertsche, A. Capra, C. Carruth, C. L. Cesar, M. Charlton, S. Cohen, R. Collister, S. Eriksson, A. Evans, N. Evetts, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, J. S. Hangst, W. N. Hardy, M. E. Hayden, C. A. Isaac, M. A. Johnson, S. A. Jones, S. Jonsell, L. Kurchaninov, N. Madsen, M. Mathers, D. Maxwell, J. T. K. Mckenna, S. Menary, T. Momose, J. J. Munich, K. Olchanski, A. Olin, P. Pusa, C. O. Rasmussen, F. Robicheaux, R. L. Sacramento, M. Sameed, E. Sarid, D. M. Silveira, C. So, G. Stutter, J. E. Thompson, R. I. Thompson, D. P. Van Der Werf, J. S. Wurtele
Enhanced Control And Reproducibility Of Non-Neutral Plasmas, Timothy Tharp, M. Ahmadi, B. X. R. Alves, C. J. Baker, W. Bertsche, A. Capra, C. Carruth, C. L. Cesar, M. Charlton, S. Cohen, R. Collister, S. Eriksson, A. Evans, N. Evetts, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, J. S. Hangst, W. N. Hardy, M. E. Hayden, C. A. Isaac, M. A. Johnson, S. A. Jones, S. Jonsell, L. Kurchaninov, N. Madsen, M. Mathers, D. Maxwell, J. T. K. Mckenna, S. Menary, T. Momose, J. J. Munich, K. Olchanski, A. Olin, P. Pusa, C. O. Rasmussen, F. Robicheaux, R. L. Sacramento, M. Sameed, E. Sarid, D. M. Silveira, C. So, G. Stutter, J. E. Thompson, R. I. Thompson, D. P. Van Der Werf, J. S. Wurtele
Physics Faculty Research and Publications
The simultaneous control of the density and particle number of non-neutral plasmas confined in Penning-Malmberg traps is demonstrated. Control is achieved by setting the plasma’s density by applying a rotating electric field while simultaneously fixing its axial potential via evaporative cooling. This novel method is particularly useful for stabilizing positron plasmas, as the procedures used to collect positrons from radioactive sources typically yield plasmas with variable densities and particle numbers; it also simplifies optimization studies that require plasma parameter scans. The reproducibility achieved by applying this technique to the positron and electron plasmas used by the ALPHA antihydrogen experiment at …