2,954 results on '"Savage, M."'
Search Results
2. The Future of High Energy Physics Software and Computing
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Elvira, V. Daniel, Gottlieb, Steven, Gutsche, Oliver, Nachman, Benjamin, Bailey, S., Bhimji, W., Boyle, P., Cerati, G., Kind, M. Carrasco, Cranmer, K., Davies, G., Elvira, V. D., Gardner, R., Heitmann, K., Hildreth, M., Hopkins, W., Humble, T., Lin, M., Onyisi, P., Qiang, J., Pedro, K., Perdue, G., Roberts, A., Savage, M., Shanahan, P., Terao, K., Whiteson, D., and Wuerthwein, F.
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High Energy Physics - Experiment ,High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,High Energy Physics - Theory - Abstract
Software and Computing (S&C) are essential to all High Energy Physics (HEP) experiments and many theoretical studies. The size and complexity of S&C are now commensurate with that of experimental instruments, playing a critical role in experimental design, data acquisition/instrumental control, reconstruction, and analysis. Furthermore, S&C often plays a leading role in driving the precision of theoretical calculations and simulations. Within this central role in HEP, S&C has been immensely successful over the last decade. This report looks forward to the next decade and beyond, in the context of the 2021 Particle Physics Community Planning Exercise ("Snowmass") organized by the Division of Particles and Fields (DPF) of the American Physical Society., Comment: Computational Frontier Report Contribution to Snowmass 2021; 41 pages, 1 figure. v2: missing ref and added missing topical group conveners. v3: fixed typos
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- 2022
3. Modelling daily net radiation of open water surfaces using land-based meteorological data
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Myeni, L, Savage, M J, and Clulow, A D
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- 2021
4. Sparsening Algorithm for Multi-Hadron Lattice QCD Correlation Functions
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Detmold, W., Murphy, D. J., Pochinsky, A. V., Savage, M. J., Shanahan, P. E., and Wagman, M. L.
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High Energy Physics - Lattice - Abstract
Modern advances in algorithms for lattice QCD calculations have steadily driven down the resources required to generate gauge field ensembles and calculate quark propagators, such that, in cases relevant to nuclear physics, performing quark contractions to assemble correlation functions from propagators has become the dominant cost. This work explores a propagator sparsening algorithm for forming correlation functions describing multi-hadron systems, such as light nuclei, with reduced computational cost. The algorithm constructs correlation functions from sparsened propagators defined on a coarsened lattice geometry, where the sparsened propagators are obtained from propagators computed on the full lattice. This algorithm is used to study the low-energy QCD ground-state spectrum using a single Wilson-clover lattice ensemble with $m_{\pi} \approx 800$ MeV. It is found that the extracted ground state masses and binding energies, as well as their statistical uncertainties, are consistent when determined from correlation functions constructed from sparsened and full propagators. In addition, while evidence of modified couplings to excited states is observed in sparsened correlation functions, it is demonstrated that these effects can be removed, if desired, with an inexpensive modification to the sparsened estimator., Comment: 18 pages, 5 figures, 4 tables
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- 2019
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5. FOBOS: A Next-Generation Spectroscopic Facility at the W. M. Keck Observatory
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Bundy, K., Westfall, K., MacDonald, N., Kupke, R., Savage, M., Poppett, C., Alabi, A., Becker, G., Burchett, J., Capak, P., Coil, A., Cooper, M., Cowley, D., Deich, W., Dillon, D., Edelstein, J., Guhathakurta, P., Hennawi, J., Kassis, M., Lee, K. -G., Masters, D., Miller, T., Newman, J., O'Meara, J., Prochaska, J. X., Rau, M., Rhodes, J., Rich, R. M., Rockosi, C., Romanowsky, A., Schafer, C., Schlegel, D., Shapley, A., Siana, B., Ting, Y. -S., Weisz, D., White, M., Williams, B., Wilson, G., Wilson, M., and Yan, R.
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Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
High-multiplex and deep spectroscopic follow-up of upcoming panoramic deep-imaging surveys like LSST, Euclid, and WFIRST is a widely recognized and increasingly urgent necessity. No current or planned facility at a U.S. observatory meets the sensitivity, multiplex, and rapid-response time needed to exploit these future datasets. FOBOS, the Fiber-Optic Broadband Optical Spectrograph, is a near-term fiber-based facility that addresses these spectroscopic needs by optimizing depth over area and exploiting the aperture advantage of the existing 10m Keck II Telescope. The result is an instrument with a uniquely blue-sensitive wavelength range (0.31-1.0 um) at R~3500, high-multiplex (1800 fibers), and a factor 1.7 greater survey speed and order-of-magnitude greater sampling density than Subaru's Prime Focus Spectrograph (PFS). In the era of panoramic deep imaging, FOBOS will excel at building the deep, spectroscopic reference data sets needed to interpret vast imaging data. At the same time, its flexible focal plane, including a mode with 25 deployable integral-field units (IFUs) across a 20 arcmin diameter field, enables an expansive range of scientific investigations. Its key programmatic areas include (1) nested stellar-parameter training sets that enable studies of the Milky Way and M31 halo sub-structure, as well as local group dwarf galaxies, (2) a comprehensive picture of galaxy formation thanks to detailed mapping of the baryonic environment at z~2 and statistical linking of evolving populations to the present day, and (3) dramatic enhancements in cosmological constraints via precise photometric redshifts and determined redshift distributions. In combination with Keck I instrumentation, FOBOS also provides instant access to medium-resolution spectroscopy for transient sources with full coverage from the UV to the K-band., Comment: Submitted to the Astro2020 Decadal Survey as a facilities white paper
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- 2019
6. Seismic response to evolving injection at the Rotokawa geothermal field, New Zealand
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Hopp, C, Sewell, S, Mroczek, S, Savage, M, and Townend, J
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Induced seismicity ,Fluid injection ,b-value ,Geothermal ,New Zealand ,Geophysics ,Geology ,Resources Engineering and Extractive Metallurgy ,Geochemistry & Geophysics - Abstract
Catalogs of microseismicity are routinely compiled at geothermal reservoirs and provide valuable insights into reservoir structure and fluid movement. Hypocentral locations are typically used to infer the orientations of structures and constrain the extent of the permeable reservoir. However, frequency-magnitude distributions may contain additional, and underused, information about the distribution of pressure. Here, we present a four-year catalog of seismicity for the Rotokawa geothermal field in the central Taupō Volcanic Zone, New Zealand starting two years after the commissioning of the 140 MWe Nga Awa Purua power station. Using waveform-correlation-based signal detection we double the size of the previous earthquake catalog, refine the location and orientation of two reservoir faults and identify a new structure. We find the rate of seismicity to be insensitive to major changes in injection strategy during the study period, including the injectivity decline and shift of injection away from the dominant injector, RK24. We also map the spatial distribution of the earthquake frequency-magnitude distribution, or b-value, and show that it increases from ∼1.0 to ∼1.5 with increasing depth below the reservoir. As has been proposed at other reservoirs, we infer that these spatial variations reflect the distribution of pressure in the reservoir, where areas of high b-value correspond to areas of high pore-fluid pressure and a broad distribution of activated fractures. This analysis is not routinely conducted by geothermal operators but shows promise for using earthquake b-value as an additional tool for reservoir monitoring and management.
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- 2020
7. Differential Reinforcement (DR). EBP Brief Packet
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National Professional Development Center on Autism Spectrum Disorder (NPDC) and Savage, M. N.
- Abstract
This evidence-based practice overview on Differential Reinforcement (DR) includes the following components: (1) Overview: A quick summary of salient features of the practice, including what it is, who it can be used with, what skills it has been used with, and settings for instruction; (2) Evidence-base: The "DR Evidence-base" details the NPDC criteria for inclusion as an evidence-based practice and the specific studies that meet the criteria for this practice; (3) Step-by-Step Guide: Use the "DR Step-by-Step Practice Guide" as an outline for how to plan for, use, and monitor DR. Each step includes a brief description as a helpful reminder while learning the process; (4) Implementation Checklist: Use the "DR Implementation Checklist" to determine if the practice is being implemented as intended; (5) Data Collection Sheets: Use the data collection sheets as a method to collect and analyze data to determine if progress is being made for a learner with ASD; (6) Tip Sheet for Professionals: Use the "DR Tip Sheet for Professionals" as a supplemental resource to help provide basic information about the practice to professionals working with the learner with ASD; (7) Parent Guide: Use the "DR Parent Guide" to help parents or family members understand basic information about the practice being used with their child; (8) Additional Resources: Use the "Additional Resources" to learn more about the practice; (9) Council for Exceptional Children (CEC) Standards: A list of "CEC Standards" that apply specifically to DR; and (10) Module References: A list of numerical "References" utilized for the DR module. [This brief was co-written by the Autism Focused Intervention Resources and Modules (AFIRM) team.]
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- 2017
8. Time Varying Crustal Anisotropy at Whakaari/White Island Volcano
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Mengesha, D. Y., primary, Savage, M. K., additional, Jolly, A. D., additional, and Ebinger, C. J., additional
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- 2024
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9. Quantum-Classical Computation of Schwinger Model Dynamics using Quantum Computers
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Klco, N., Dumitrescu, E. F., McCaskey, A. J., Morris, T. D., Pooser, R. C., Sanz, M., Solano, E., Lougovski, P., and Savage, M. J.
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Quantum Physics ,High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,High Energy Physics - Theory ,Nuclear Theory - Abstract
We present a quantum-classical algorithm to study the dynamics of the two-spatial-site Schwinger model on IBM's quantum computers. Using rotational symmetries, total charge, and parity, the number of qubits needed to perform computation is reduced by a factor of $\sim 5$, removing exponentially-large unphysical sectors from the Hilbert space. Our work opens an avenue for exploration of other lattice quantum field theories, such as quantum chromodynamics, where classical computation is used to find symmetry sectors in which the quantum computer evaluates the dynamics of quantum fluctuations., Comment: 5 pages, 4 figures, 23 pages supplemental, 8 figures supplemental
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- 2018
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10. Seismic Response to Injection Well Stimulation in a High-Temperature, High-Permeability Reservoir
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Hopp, C, Sewell, S, Mroczek, S, Savage, M, and Townend, J
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induced seismicity ,geothermal ,matched filter ,stress inversion ,stimulation ,Ngatamariki ,Earth Sciences ,Physical Sciences ,Geochemistry & Geophysics - Abstract
Fluid injection into the Earth's crust can induce seismic events that cause damage to local infrastructure but also offer valuable insight into seismogenesis. The factors that influence the magnitude, location, and number of induced events remain poorly understood but include injection flow rate and pressure as well as reservoir temperature and permeability. The relationship between injection parameters and injection-induced seismicity in high-temperature, high-permeability reservoirs has not been extensively studied. Here we focus on the Ngatamariki geothermal field in the central Taupō Volcanic Zone, New Zealand, where three stimulation/injection tests have occurred since 2012. We present a catalog of seismicity from 2012 to 2015 created using a matched-filter detection technique. We analyze the stress state in the reservoir during the injection tests from first motion-derived focal mechanisms, yielding an average direction of maximum horizontal compressive stress (SHmax) consistent with the regional NE-SW trend. However, there is significant variation in the direction of maximum compressive stress (σ1), which may reflect geological differences between wells. We use the ratio of injection flow rate to overpressure, referred to as injectivity index, as a proxy for near-well permeability and compare changes in injectivity index to spatiotemporal characteristics of seismicity accompanying each test. Observed increases in injectivity index are generally poorly correlated with seismicity, suggesting that the locations of microearthquakes are not coincident with the zone of stimulation (i.e., increased permeability). Our findings augment a growing body of work suggesting that aseismic opening or slip, rather than seismic shear, is the active process driving well stimulation in many environments.
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- 2019
11. Simultaneous multicolour optical and near-IR transit photometry of GJ 1214b with SOFIA
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Angerhausen, D., Dreyer, C., Placek, B., Csizmadia, Sz., Eigmueller, Ph., Godolt, M., Kitzmann, D., Mallonn, M., Becklin, E. E., Collins, P., Dunham, E. W., Grenfell, J. L., Hamilton, R. T., Kabath, P., Logsdon, S. E., Mandell, A., Mandushev, G., McElwain, M., McLean, I. S., Pfueller, E., Rauer, H., Savage, M., Shenoy, S., Vacca, W. D., Van Cleve, J. E., Wiedemann, M., and Wolf, J.
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Solar and Stellar Astrophysics - Abstract
The benchmark exoplanet GJ 1214b is one of the best studied transiting planets in the transition zone between rocky Earth-sized planets and gas or ice giants. This class of super-Earth/mini-Neptune planets is unknown in our Solar System, yet is one of the most frequently detected classes of exoplanets. Understanding the transition from rocky to gaseous planets is a crucial step in the exploration of extrasolar planetary systems, in particular with regard to the potential habitability of this class of planets. GJ 1214b has already been studied in detail from various platforms at many different wavelengths. Our airborne observations with SOFIA add information in the Paschen-alpha cont. 1.9 micron infrared wavelength band, which is not accessible by any other current ground- or space-based instrument due to telluric absorption or limited spectral coverage. We used FLIPO and FPI+ on SOFIA to comprehensively analyse the transmission signal of the possible water-world GJ 1214b through photometric observations during transit in three optical and one infrared channels. We present four simultaneous light curves and corresponding transit depths in three optical and one infrared channel, which we compare to previous observations and state-of-the-art synthetic atmospheric models of GJ 1214b. The final precision in transit depth is between 1.5 and 2.5 times the theoretical photon noise limit, not sensitive enough to constrain the theoretical models any better than previous observations. This is the first exoplanet observation with SOFIA that uses its full set of instruments available to exoplanet spectrophotometry. Therefore we use these results to evaluate SOFIA's potential in this field and suggest future improvements., Comment: Accepted for publication in Astronomy and Astrophysics
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- 2017
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12. Spatiotemporal Evolution of Slow Slip Events at the Offshore Hikurangi Subduction Zone in 2019 Using GNSS, InSAR, and Seafloor Geodetic Data.
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Woods, K., Wallace, L. M., Williams, C. A., Hamling, I. J., Webb, S. C., Ito, Y., Palmer, N., Hino, R., Suzuki, S., Savage, M. K., Warren‐Smith, E., and Mochizuki, K.
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SLOW earthquakes ,GLOBAL Positioning System ,SUBDUCTION ,SYNTHETIC aperture radar ,PLATE tectonics - Abstract
Detecting crustal deformation during transient deformation events at offshore subduction zones remains challenging. The spatiotemporal evolution of slow slip events (SSEs) on the offshore Hikurangi subduction zone, New Zealand, during February–July 2019, is revealed through a time‐dependent inversion of onshore and offshore geodetic data that also accounts for spatially varying elastic crustal properties. Our model is constrained by seafloor pressure time series (as a proxy for vertical seafloor deformation), onshore continuous Global Navigation Satellite System (GNSS) data, and Interferometric Synthetic Aperture Radar displacements. Large GNSS displacements onshore and uplift of the seafloor (10–33 mm) require peak slip during the event of 150 to >200 mm at 6–12 km depth offshore Hawkes Bay and Gisborne, comparable to maximum slip observed during previous seafloor pressure deployments at north Hikurangi. The onshore and offshore data reveal a complex evolution of the SSE, over a period of months. Seafloor pressure data indicates the slow slip may have persisted longer near the trench than suggested by onshore GNSS stations in both the Gisborne and Hawkes Bay regions. Seafloor pressure data also reveal up‐dip migration of SSE slip beneath Hawke Bay occurred over a period of a few weeks. The SSE source region appears to coincide with locations of the March 1947 Mw 7.0–7.1 tsunami earthquake offshore Gisborne and estimated great earthquake rupture sources from paleoseismic investigations offshore Hawkes Bay, suggesting that the shallow megathrust at north and central Hikurangi is capable of both seismic and aseismic rupture. Plain Language Summary: Subduction zones, where one tectonic plate dives beneath another, generate the planet's largest earthquakes. They also host an important mode of fault slip called "slow slip events (SSEs)," which are essentially earthquakes in slow motion. The Hikurangi subduction zone, where the Pacific Plate subducts beneath New Zealand hosts large and frequent SSEs near the trench, where the plate boundary emerges at the seabed, requiring seafloor instrumentation to investigate them. Seafloor pressure measurements can track centimeter‐level up or down movement of the seafloor during slow slip, and reveal offshore displacement during a large 2019 SSE at the Hikurangi subduction zone. The 2019 event involved substantial migration, beginning at ∼15 km depth, and expanding to the trench over a period of several weeks. We also show that the same areas which have ruptured in previous seismic earthquakes (that involved faster slip) can also rupture slowly, in SSEs. This raises the possibility that regions where we currently observe SSEs could also produce seismic events. This result also demands that more work must be done to understand the physical processes that enable the same part of a fault to rupture both fast and slow at different times. Key Points: Central Hikurangi slow slip events (SSEs) propagate up‐dip over a period of weeks to monthsSeafloor geodetic data reveal that shallow SSEs may last longer than onshore Global Navigation Satellite System data suggestThe same portions of a shallow megathrust can host both large seismic and aseismic rupture [ABSTRACT FROM AUTHOR]
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- 2024
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13. Design of a precision cryogenic rotary stage for optic or mask selection for the SCALES instrument mounted to the Keck 2 Telescope
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Navarro, Ramón, Jedamzik, Ralf, Ratliff, C., MacDonald, N., Cabak, J., Deich, W., Sandford, D., Gonzales, M., Skemer, A., Sallum, S., Stelter, D., Hunter, A., Kupke, R., Dillon, D., Marques, D., Rodriguez, C., Savage, M., Kassis, M., Lyke, J., and Hasan, A.
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- 2024
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14. The value of whole exome sequencing for genetic diagnosis in a patient with Bloom syndrome
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Cottrell, E., Ladha, T., Borysewicz-Sańczyk, H., Sawicka, B., Savage, M. O., Bossowski, A. T., and Storr, H. L.
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- 2021
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15. P145 Phagocyte responses to gut-derived C. albicans are modified in inflammatory bowel disease
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Mathew, L, primary, Carlson, S, additional, Savage, M, additional, Pardieu, C, additional, Sze, N, additional, Munro, C, additional, Naglik, J, additional, Stagg, A, additional, Kok, K, additional, Lindsay, J O, additional, and McCarthy, N, additional
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- 2024
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16. Evaluating the relationship between the nutrient intake of lactating women and their breast milk nutritional profile: a systematic review and narrative synthesis
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Falize, Coralie, primary, Savage, M., additional, Jeanes, Yvonne M., additional, and Dyall, Simon C., additional
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- 2023
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17. Quarkonium-Nucleus Bound States from Lattice QCD
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Beane, S. R., Chang, E., Cohen, S. D., Detmold, W., Lin, H. -W., Orginos, K., Parreño, A., and Savage, M. J.
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High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
Quarkonium-nucleus systems are composed of two interacting hadronic states without common valence quarks, which interact primarily through multi-gluon exchanges, realizing a color van der Waals force. We present lattice QCD calculations of the interactions of strange and charm quarkonia with light nuclei. Both the strangeonium-nucleus and charmonium-nucleus systems are found to be relatively deeply bound when the masses of the three light quarks are set equal to that of the physical strange quark. Extrapolation of these results to the physical light-quark masses suggests that the binding energy of charmonium to nuclear matter is B < 40 MeV., Comment: published version
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- 2014
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18. Magnetic moments of light nuclei from lattice quantum chromodynamics
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Beane, S. R., Chang, E., Cohen, S., Detmold, W., Lin, H. W., Orginos, K., Parreno, A., Savage, M. J., and Tiburzi, B. C.
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High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
We present the results of lattice QCD calculations of the magnetic moments of the lightest nuclei, the deuteron, the triton and ${}^3$He, along with those of the neutron and proton. These calculations, performed at quark masses corresponding to $m_\pi \sim 800$ MeV, reveal that the structure of these nuclei at unphysically heavy quark masses closely resembles that at the physical quark masses. In particular, we find that the magnetic moment of ${}^3$He differs only slightly from that of a free neutron, as is the case in nature, indicating that the shell-model configuration of two spin-paired protons and a valence neutron captures its dominant structure. Similarly a shell-model-like moment is found for the triton, $\mu_{{}^3{\rm H}} \sim \mu_p$. The deuteron magnetic moment is found to be equal to the nucleon isoscalar moment within the uncertainties of the calculations., Comment: 5 pages, 4 figures, published version
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- 2014
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19. Nuclear \sigma-terms and Scalar-Isoscalar WIMP-Nucleus Interactions from Lattice QCD
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Beane, S. R., Cohen, S. D., Detmold, W., Lin, H. -W., and Savage, M. J.
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High Energy Physics - Phenomenology ,High Energy Physics - Lattice ,Nuclear Theory - Abstract
It has been argued that the leading scalar-isoscalar WIMP-nucleus interactions receive parametrically enhanced contributions in the context of nuclear effective field theories. These contributions arise from meson-exchange currents (MECs) and potentially modify the impulse approximation estimates of these interactions by 10--60%. We point out that these MECs also contribute to the quark mass dependence of nuclear binding energies, that is, nuclear \sigma-terms. In this work, we use recent lattice QCD calculations of the binding energies of the deuteron, He-3 and He-4 at pion masses near 500 MeV and 800 MeV, combined with the experimentally determined binding energies at the physical point, to provide approximate determinations of the \sigma-terms for these light nuclei. For each nucleus, we find that the deviation of the corresponding nuclear \sigma-term from the single-nucleon estimate is at the few percent level, in conflict with the conjectured enhancement. As a consequence, lattice QCD calculations currently indicate that the cross sections for scalar-isoscalar WIMP-nucleus interactions arising from fundamental WIMP interactions with quarks do not suffer from significant uncertainties due to enhanced meson-exchange currents., Comment: journal version
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- 2013
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20. Nucleon-Nucleon Scattering Parameters in the Limit of SU(3) Flavor Symmetry
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Beane, S. R., Chang, E., Cohen, S. D., Detmold, W., Junnarkar, P., Lin, H. W., Luu, T. C., Orginos, K., Parreno, A., Savage, M. J., and Walker-Loud, A.
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High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
The scattering lengths and effective ranges that describe low-energy nucleon-nucleon scattering are calculated in the limit of SU(3)-flavor symmetry at the physical strange-quark mass with Lattice Quantum Chromodynamics. The calculations are performed with an isotropic clover discretization of the quark action in three volumes with spatial extents of L \sim 3.4 fm, 4.5fm and 6.7 fm, and with a lattice spacing of b \sim 0.145 fm. With determinations of the energies of the two-nucleon systems (both of which contain bound states at these up and down quark masses) at rest and moving in the lattice volume, Luscher's method is used to determine the low-energy phase shifts in each channel, from which the scattering length and effective range are obtained. The scattering parameters, in the 1S0 channel are found to be m_pi a^(1S0) = 9.50^{+0.78}_{-0.69}^{+1.10}_{-0.80} and m_pi r^(1S0) = {4.61^{+0.29}_{-0.31}^{+0.24}_{-0.26}, and in the 3S1 channel are m_pi a^(3S1) = 7.45^{+0.57}_{-0.53}^{+0.71}_{-0.49} and m_pi r^(3S1) = 3.71^{+0.28}_{-0.31}^{+0.28}_{-0.35}. These values are consistent with the two-nucleon system exhibiting Wigner's supermultiplet symmetry, which becomes exact in the limit of large-N_c. In both spin channels, the phase shifts change sign at higher momentum, near the start of the t-channel cut, indicating that the nuclear interactions have a repulsive core even at the SU(3)-symmetric point., Comment: 17 pages, 29 figures
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- 2013
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21. Light Nuclei and Hypernuclei from Quantum Chromodynamics in the Limit of SU(3) Flavor Symmetry
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Beane, S. R., Chang, E., Cohen, S. D., Detmold, W., Lin, H. W., Luu, T. C., Orginos, K., Parreno, A., Savage, M. J., and Walker-Loud, A.
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High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
The binding energies of a range of nuclei and hypernuclei with atomic number A <= 4 and strangeness |s| <= 2, including the deuteron, di-neutron, H-dibaryon, 3He, Lambda 3He, Lambda 4He, and Lambda Lambda 4He, are calculated in the limit of flavor-SU(3) symmetry at the physical strange quark mass with quantum chromodynamics (without electromagnetic interactions). The nuclear states are extracted from Lattice QCD calculations performed with n_f=3 dynamical light quarks using an isotropic clover discretization of the quark-action in three lattice volumes of spatial extent L ~ 3.4 fm, 4.5 fm and 6.7 fm, and with a single lattice spacing b ~ 0.145 fm., Comment: 35 pages, 45 figures Increased statistics, enhanced discussion, fixed typos
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- 2012
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22. Early Science with SOFIA, the Stratospheric Observatory for Infrared Astronomy
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Young, E. T., Becklin, E. E., Marcum, P. M., Roellig, T. L., De Buizer, J. M., Herter, T. L., Güsten, R., Dunham, E. W., Temi, P., Andersson, B. -G., Backman, D., Burgdorf, M., Caroff, L. J., Casey, S. C., Davidson, J. A., Erickson, E. F., Gehrz, R. D., Harper, D. A., Harvey, P. M., Helton, L. A., Horner, S. D., Howard, C. D., Klein, R., Krabbe, A., McLean, I. S., Meyer, A. W., Miles, J. W., Morris, M. R., Reach, W. T., Rho, J., Richter, M. J., Roeser, H. -P., Sandell, G., Sankrit, R., Savage, M. L., Smith, E. C., Shuping, R. Y., Vacca, W. D., Vaillancourt, J. E., Wolf, J., and Zinnecker, H.
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Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
The Stratospheric Observatory for Infrared Astronomy (SOFIA) is an airborne observatory consisting of a specially modified Boeing 747SP with a 2.7-m telescope, flying at altitudes as high as 13.7 km (45,000 ft). Designed to observe at wavelengths from 0.3 micron to 1.6 mm, SOFIA operates above 99.8 % of the water vapor that obscures much of the infrared and submillimeter. SOFIA has seven science instruments under development, including an occultation photometer, near-, mid-, and far-infrared cameras, infrared spectrometers, and heterodyne receivers. SOFIA, a joint project between NASA and the German Aerospace Center DLR, began initial science flights in 2010 December, and has conducted 30 science flights in the subsequent year. During this early science period three instruments have flown: the mid-infrared camera FORCAST, the heterodyne spectrometer GREAT, and the occultation photometer HIPO. This article provides an overview of the observatory and its early performance., Comment: 7 pages, 4 figures; Accepted for publication by the Astrophysical Journal Letters
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- 2012
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23. Hyperon-Nucleon Interactions and the Composition of Dense Nuclear Matter from Quantum Chromodynamics
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Beane, S. R., Chang, E., Cohen, S. D., Detmold, W., Lin, H. -W., Luu, T. C., Orginos, K., Parreno, A., Savage, M. J., and Walker-Loud, A.
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High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
The low-energy neutron-Sigma^- interactions determine, in part, the role of the strange quark in dense matter, such as that found in astrophysical environments. The scattering phase shifts for this system are obtained from a numerical evaluation of the QCD path integral using the technique of Lattice QCD. Our calculations, performed at a pion mass of m_pi ~ 389 MeV in two large lattice volumes, and at one lattice spacing, are extrapolated to the physical pion mass using effective field theory. The interactions determined from QCD are consistent with those extracted from hyperon-nucleon experimental data within uncertainties, and strengthen theoretical arguments that the strange quark is a crucial component of dense nuclear matter., Comment: 5 pages, 4 figures
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- 2012
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24. The Deuteron and Exotic Two-Body Bound States from Lattice QCD
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Beane, S. R., Chang, E., Detmold, W., Lin, H. W., Luu, T. C., Orginos, K., Parreno, A., Savage, M. J., Torok, A., and Walker-Loud, A.
- Subjects
High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
Results of a high-statistics, multi-volume Lattice QCD exploration of the deuteron, the di-neutron, the H-dibaryon, and the Xi-Xi- system at a pion mass of m ~ 390 MeV are presented. Calculations were performed with an anisotropic n_f = 2+1 Clover discretization in four lattice volumes of spatial extent L ~ 2.0, 2.5, 3.0 and 4.0 fm, with a lattice spacing of b_s ~ 0.123 fm in the spatial-direction, and b_t ~ b_s/3.5 in the time-direction. The Xi-Xi- is found to be bound by B_{Xi-Xi-} = 14.0(1.4)(6.7) MeV, consistent with expectations based upon phenomenological models and low-energy effective field theories constrained by nucleon-nucleon and hyperon-nucleon scattering data at the physical light-quark masses. We find weak evidence that both the deuteron and the di-neutron are bound at this pion mass, with binding energies of B_d = 11(05)(12) MeV and B_{nn} = 7.1(5.2)(7.3) MeV, respectively. With an increased number of measurements and a refined analysis, the binding energy of the H-dibaryon is B_H = 13.2(1.8)(4.0) MeV at this pion mass, updating our previous result., Comment: 25 pages, 30 figures
- Published
- 2011
- Full Text
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25. SU(2) Low-Energy Constants from Mixed-Action Lattice QCD
- Author
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Beane, S. R., Detmold, W., Junnarkar, P. M., Luu, T. C., Orginos, K., Parreno, A., Savage, M. J., Torok, A., and Walker-Loud, A.
- Subjects
High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
An analysis of the pion mass and pion decay constant is performed using mixed-action Lattice QCD calculations with domain-wall valence quarks on ensembles of rooted, staggered n_f = 2+1 MILC configurations. Calculations were performed at two lattice spacings of b~0.125 fm and b~0.09 fm, at two strange quark masses, multiple light quark masses, and a number of lattice volumes. The ratios of light quark to strange quark masses are in the range 0.1 <= m_l / m_s <= 0.6, while pion masses are in the range 235 < m_\pi < 680 MeV. A two-flavor chiral perturbation theory analysis of the Lattice QCD calculations constrains the Gasser-Leutwyler coefficients bar{l}_3 and bar{l}_4 to be bar{l}_3 = 4.04(40)(+73-55) and bar{l}_4 = 4.30(51)(+84-60). All systematic effects in the calculations are explored, including those from the finite lattice space-time volume, the finite lattice spacing, and the finite fifth dimension in the domain-wall quark action. A consistency is demonstrated between a chiral perturbation theory analysis at fixed lattice spacing combined with a leading order continuum extrapolation, and the mixed-action chiral perturbation theory analysis which explicitly includes the leading order discretization effects. Chiral corrections to the pion decay constant are found to give f_\pi / f = 1.062(26)(+42-40) where f is the decay constant in the chiral limit. The most recent scale setting by the MILC Collaboration yields a postdiction of f_\pi = 128.2(3.6)(+4.4-6.0)(+1.2-3.3) MeV at the physical pion mass., Comment: 28 pages, 9 figures; version 2 accepted for publication in PRD
- Published
- 2011
- Full Text
- View/download PDF
26. The I=2 pipi S-wave Scattering Phase Shift from Lattice QCD
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Beane, S. R., Chang, E., Detmold, W., Lin, H. W., Luu, T. C., Orginos, K., Parreno, A., Savage, M. J., Torok, A., and Walker-Loud, A.
- Subjects
High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
The pi+pi+ s-wave scattering phase-shift is determined below the inelastic threshold using Lattice QCD. Calculations were performed at a pion mass of m_pi~390 MeV with an anisotropic n_f=2+1 clover fermion discretization in four lattice volumes, with spatial extent L~2.0, 2.5, 3.0 and 3.9 fm, and with a lattice spacing of b_s~0.123 fm in the spatial direction and b_t b_s/3.5 in the time direction. The phase-shift is determined from the energy-eigenvalues of pi+pi+ systems with both zero and non-zero total momentum in the lattice volume using Luscher's method. Our calculations are precise enough to allow for a determination of the threshold scattering parameters, the scattering length a, the effective range r, and the shape-parameter P, in this channel and to examine the prediction of two-flavor chiral perturbation theory: m_pi^2 a r = 3+O(m_pi^2/Lambda_chi^2). Chiral perturbation theory is used, with the Lattice QCD results as input, to predict the scattering phase-shift (and threshold parameters) at the physical pion mass. Our results are consistent with determinations from the Roy equations and with the existing experimental phase shift data., Comment: 22 pages, 16 figures
- Published
- 2011
- Full Text
- View/download PDF
27. High Statistics Analysis using Anisotropic Clover Lattices: (IV) Volume Dependence of Light Hadron Masses
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Beane, S. R., Chang, E., Detmold, W., Lin, H. W., Luu, T. C., Orginos, K., Parreno, A., Savage, M. J., Torok, A., and Walker-Loud, A.
- Subjects
High Energy Physics - Lattice - Abstract
The volume dependence of the octet baryon masses and relations among them are explored with Lattice QCD. Calculations are performed with n_f=2+1 clover fermion discretization in four lattice volumes, with spatial extent L ~ 2.0, 2.5, 3.0 and 3.9 fm, with an anisotropic lattice spacing of b_s ~ 0.123 fm in the spatial direction, and b_t = b_s/3.5 in the time direction, and at a pion mass of m_pi ~ 390 MeV. The typical precision of the ground-state baryon mass determination is ~0.2%, enabling a precise exploration of the volume dependence of the masses, the Gell-Mann--Okubo mass relation, and of other mass combinations. A comparison of the volume dependence with the predictions of heavy baryon chiral perturbation theory is performed in both the SU(2)_L X SU(2)_R and SU(3)_L X SU(3)_R expansions. Predictions of the three-flavor expansion for the hadron masses are found to describe the observed volume dependences reasonably well. Further, the Delta-N-pi axial coupling constant is extracted from the volume dependence of the nucleon mass in the two-flavor expansion, with only small modifications in the three-flavor expansion from the inclusion of kaons and etas. At a given value of m_pi L, the finite-volume contributions to the nucleon mass are predicted to be significantly smaller at m_pi ~ 140 MeV than at m_pi ~ 390 MeV due to a coefficient that scales as ~ m_pi^3. This is relevant for the design of future ensembles of lattice gauge-field configurations. Finally, the volume dependence of the pion and kaon masses are analyzed with two-flavor and three-flavor chiral perturbation theory., Comment: 34 pages, 45 figures
- Published
- 2011
- Full Text
- View/download PDF
28. Present Constraints on the H-dibaryon at the Physical Point from Lattice QCD
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Beane, S. R., Chang, E., Detmold, W., Joo, B., Lin, H. W., Luu, T. C., Orginos, K., Parreno, A., Savage, M. J., Torok, A., and Walker-Loud, A.
- Subjects
High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Experiment ,Nuclear Theory - Abstract
The current constraints from lattice QCD on the existence of the H-dibaryon are discussed. With only two significant lattice QCD calculations of the H-dibaryon binding energy at approximately the same lattice spacing, the forms of the chiral and continuum extrapolations to the physical point are not determined. In this brief report, we consider the constraints on the H-dibaryon imposed by two simple chiral extrapolations. In both instances, the extrapolation to the physical pion mass allows for a bound H-dibaryon or a near-threshold scattering state. Further lattice QCD calculations are required to clarify this situation., Comment: 8 pages, 2 figures, 1 table; revised for the journal
- Published
- 2011
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29. Evidence for a Bound H-dibaryon from Lattice QCD
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Beane, S. R., Chang, E., Detmold, W., Joo, B., Lin, H. W., Luu, T. C., Orginos, K., Parreno, A., Savage, M. J., Torok, A., and Walker-Loud, A.
- Subjects
High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
We present evidence for the existence of a bound H-dibaryon, an I=0, J=0, s=-2 state with valence quark structure uuddss, at a pion mass of m_pi ~ 389 MeV. Using the results of Lattice QCD calculations performed on four ensembles of anisotropic clover gauge-field configurations, with spatial extents of L ~ 2.0, 2.5, 3.0 and 3.9 fm at a spatial lattice spacing of b ~ 0.123 fm, we find an H-dibaryon bound by B = 16.6 +- 2.1 +- 4.6 MeV at a pion mass of m_pi ~ 389 MeV., Comment: 4 pages and 3 figures. v2 accepted by PRL
- Published
- 2010
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30. Nuclear Physics from Lattice QCD
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Beane, S. R., Detmold, W., Orginos, K., and Savage, M. J.
- Subjects
High Energy Physics - Lattice ,Nuclear Theory - Abstract
We review recent progress toward establishing lattice Quantum Chromodynamics as a predictive calculational framework for nuclear physics. A survey of the current techniques that are used to extract low-energy hadronic scattering amplitudes and interactions is followed by a review of recent two-body and few-body calculations by the NPLQCD collaboration and others. An outline of the nuclear physics that is expected to be accomplished with Lattice QCD in the next decade, along with estimates of the required computational resources, is presented., Comment: 56 pages, 39 pdf figures. Final published version
- Published
- 2010
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31. Evaluating the relationship between the nutrient intake of lactating women and their breast milk nutritional profile: a systematic review and narrative synthesis.
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Falize, Coralie, Savage, M., Jeanes, Yvonne M., and Dyall, Simon C.
- Subjects
BREASTFEEDING ,FOOD consumption ,NUTRITIONAL assessment ,CINAHL database ,OMEGA-3 fatty acids ,BREAST milk ,NUTRITIONAL requirements ,LACTATION ,MEDLINE ,VEGETARIANISM ,NUTRITIONAL status ,ONLINE information services - Abstract
Maternal diet influences breast milk nutritional profile; however, it is unclear which nutrients and contaminants are particularly responsive to short- and long-term changes in maternal intake, and the impact of specific exclusion diets, such as vegan or vegetarian. This study systematically reviewed the literature on the effects of maternal nutrient intake, including exclusion diets, on both the nutrient and contaminant content of breast milk. The electronic databases, PubMed, CENTRAL, Web of Science and CINALH were systematically searched until 4 June 2023, with additionally searches of reference lists (PROSPERO, CRD42020221577). The quality of the studies was examined using Cochrane Risk of Bias tool and Newcastle–Ottawa scale. Eighty-eight studies (n 6577) met the search criteria. Due to high heterogeneity, meta-analysis was not possible. There was strong evidence of response to maternal intakes for DHA and EPA, vitamins A, E and K, iodine and Se in breast milk composition, some evidence of response for α -linolenic acid, B vitamins, vitamin C and D, ovalbumin, tyrosine and contaminants, and insufficient evidence to identify the effects arachidonic acid, Cu, Fe, Zn and choline. The paucity of evidence and high heterogeneity among studies reflects the need for more high-quality trials. However, this review identified the importance of maternal intake in the nutritional content of breast milk for a wide range of nutrients and supports the recommendation for supplementation of DHA and vitamin B
12 for those on restrictive diets. [ABSTRACT FROM AUTHOR]- Published
- 2024
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32. Meniscus Roll Coating: Steady Flows and Instabilities
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Savage, M., primary
- Published
- 2019
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33. f_K/f_pi in Full QCD with Domain Wall Valence Quarks
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Beane, S. R., Bedaque, P. F., Orginos, K., and Savage, M. J.
- Subjects
High Energy Physics - Lattice ,High Energy Physics - Phenomenology - Abstract
We compute the ratio of pseudoscalar decay constants f_K/f_pi using domain-wall valence quarks and rooted improved Kogut-Susskind sea quarks. By employing continuum chiral perturbation theory, we extract the Gasser-Leutwyler low-energy constant L_5, and extrapolate f_K/f_pi to the physical point. We find: f_K/f_pi = 1.218 (+- 0.002) (+0.011 -0.024) where the first error is statistical and the second error is an estimate of the systematic due to chiral extrapolation and fitting procedures. This value agrees within the uncertainties with the determination by the MILC collaboration, calculated using Kogut-Susskind valence quarks, indicating that systematic errors arising from the choice of lattice valence quark are small., Comment: 14 pages, 9 figures
- Published
- 2006
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34. Nucleon-Nucleon Scattering From Fully-Dynamical Lattice QCD
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Beane, S. R., Bedaque, P. F., Orginos, K., and Savage, M. J.
- Subjects
High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
We present results of the first fully-dynamical lattice QCD determination of nucleon-nucleon scattering lengths in the 1S0 channel and 3S1-3D1 coupled channels. The calculations are performed with domain-wall valence quarks on the MILC staggered configurations with lattice spacing of b=0.125 fm in the isospin-symmetric limit, and in the absence of electromagnetic interactions., Comment: 4 pages, 4 figures
- Published
- 2006
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- View/download PDF
35. Warm Molecular Gas Traced with CO J=7->6 in the Galaxy's Central 2 Parsecs: Dynamical Heating of the Circumnuclear Disk
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Bradford, C. M., Stacey, G. J., Nikola, T., Bolatto, A. D., Jackson, J. M., Savage, M. L., and Davidson, J. A.
- Subjects
Astrophysics - Abstract
We present an 11 arcsec resolution map of the central two parsecs of the Galaxy in the CO J =7->6 rotational transition. The CO emission shows rotation about Sgr A*, but also evidence for non-circular turbulent motion and a clumpy morphology. We combine our dataset with available CO measurements to model the physical conditions in the disk. We find that the molecular gas in the region is both warm and dense, with T~200-300 K, n_H2~50,000-70,000 cm^-3. The mass of warm molecular gas we measure in the central two parsecs is at least 2000 M_solar, about 20 times the UV-excited atomic gas mass, ruling out an UV heating scenario for the molecular material. We compare the available spectral tracers with theoretical models and conclude that molecular gas is heated with magneto-hydrodynamic shocks with v~10-20 kms and B~0.3-0.5 mG. Using the conditions derived with the CO analysis, we include the other important coolants--neutral oxygen and molecular hydrogen--to estimate the total cooling budget of the molecular material. We derive a mass to luminosity ratio of 2-3 M_solar/ L_solar, which is consistent with the total power dissipated via turbulent decay in 0.1 pc cells with v_rms~15 kms. These size and velocity scales are comparable to the observed clumping scale and the velocity dispersion. At this rate, the material near Sgr A* its dissipating its orbital energy on an orbital timescale, and cannot last for more than a few orbits. Our conclusions support a scenario in which the features near Sgr A* such as the CND and northern arm are generated by infalling clouds with low specific angular momentum., Comment: 31 pages, including 5 figures, accepted for publication in ApJ
- Published
- 2005
- Full Text
- View/download PDF
36. Two Nucleons on a Lattice
- Author
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Beane, S. R., Bedaque, P. F., Parreno, A., and Savage, M. J.
- Subjects
High Energy Physics - Lattice ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
The two-nucleon sector is near an infrared fixed point of QCD and as a result the S-wave scattering lengths are unnaturally large compared to the effective ranges and shape parameters. It is usually assumed that a lattice QCD simulation of the two-nucleon sector will require a lattice that is much larger than the scattering lengths in order to extract quantitative information. In this paper we point out that this does not have to be the case: lattice QCD simulations on much smaller lattices will produce rigorous results for nuclear physics., Comment: 13 pages, 6 figures
- Published
- 2003
- Full Text
- View/download PDF
37. Exploring Hyperons and Hypernuclei with Lattice QCD
- Author
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Beane, S. R., Bedaque, P. F., Parreno, A., and Savage, M. J.
- Subjects
Nuclear Theory ,High Energy Physics - Lattice ,High Energy Physics - Phenomenology - Abstract
In this work we outline a program for lattice QCD that would provide a first step toward understanding the strong and weak interactions of strange baryons. The study of hypernuclear physics has provided a significant amount of information regarding the structure and weak decays of light nuclei containing one or two Lambda's, and Sigma's. From a theoretical standpoint, little is known about the hyperon-nucleon interaction, which is required input for systematic calculations of hypernuclear structure. Furthermore, the long-standing discrepancies in the P-wave amplitudes for nonleptonic hyperon decays remain to be understood, and their resolution is central to a better understanding of the weak decays of hypernuclei. We present a framework that utilizes Luscher's finite-volume techniques in lattice QCD to extract the scattering length and effective range for Lambda-N scattering in both QCD and partially-quenched QCD. The effective theory describing the nonleptonic decays of hyperons using isospin symmetry alone, appropriate for lattice calculations, is constructed., Comment: 24 pages, 7 figures
- Published
- 2003
- Full Text
- View/download PDF
38. Long-term trends and variability in the dryland microclimate of the Northern Cape Province, South Africa
- Author
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Strydom, S., Savage, M. J., and Clulow, A. D.
- Published
- 2019
- Full Text
- View/download PDF
39. CO (J=7->6) Observations of NGC 253: Cosmic Ray Heated Warm Molecular Gas
- Author
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Bradford, C. M., Nikola, T., Stacey, G. J., Bolatto, A. D., Jackson, J. M., Savage, M. L., Davidson, J. A., and Higdon, S. J.
- Subjects
Astrophysics - Abstract
We report observations of the CO J=7->6 transition toward the starburst nucleus of NGC 253. This is the highest-excitation CO measurement in this source to date, and allows an estimate of the molecular gas excitation conditions. Comparison of the CO line intensities with a large velocity gradient, escape probability model indicates that the bulk of the 2-5 x 10^7 solar masses of molecular gas in the central 180 pc is highly excited. A model with T ~ 120 K, n_H_2 ~ 4.5 x 10^4 cm^-3 is consistent with the observed CO intensities as well as the rotational H2 lines observed with ISO. The inferred mass of warm, dense molecular gas is 10--30 times the atomic gas mass as traced through its [CII] and [OI] line emission. This large mass ratio is inconsistent with photodissociation region models where the gas is heated by far-UV starlight. It is also not likely that the gas is heated by shocks in outflows or cloud-cloud collisions. We conclude that the best mechanism for heating the gas is cosmic rays, which provide a natural means of uniformly heating the full volume of molecular clouds. With the tremendous supernova rate in the nucleus of NGC 253, the CR heating rate is at least ~800 times greater than in the Galaxy, more than sufficient to match the cooling observed in the CO lines., Comment: 12+ pages, 4 figures, to appear in The Astrophysical Journal (now includes tables)
- Published
- 2002
- Full Text
- View/download PDF
40. SPIFI: a direct-detection imaging spectrometer for submillimeter wavelengths
- Author
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Bradford, C. M., Stacey, G. J., Swain, M. R., Nikola, T., Bolatto, A. D., Jackson, J. M., Savage, M. L., Davidson, J. A., and Ade, P.
- Subjects
Astrophysics - Abstract
The South Pole Imaging Fabry-Perot Interferometer (SPIFI) is the first instrument of its kind -- a direct-detection imaging spectrometer for astronomy in the submillimeter band. SPIFI's focal plane is a square array of 25 silicon bolometers cooled to 60 mK; the spectrometer consists of two cryogenic, scanning Fabry-Perot interferometers in series with a 60 mK bandpass filter. The instrument operates in the short submillimeter windows (350 microns, 450 microns) available from the ground, with spectral resolving power selectable between 500 and 10000. At present, SPIFI's sensitivity is within a factor 1.5-3 of the photon background limit, comparable to the best heterodyne spectrometers. The instrument's large bandwidth and mapping capability provide substantial advantages for specific astrophysical projects, including deep extragalactic observations. In this article we present the motivation for and design of SPIFI and its operational characteristics on the telescope., Comment: 36 pages with 10 figures
- Published
- 2002
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- View/download PDF
41. Towards a Perturbative Theory of Nuclear Forces
- Author
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Beane, S. R., Bedaque, P. F., Savage, M. J., and van Kolck, U.
- Subjects
Nuclear Theory ,High Energy Physics - Lattice ,High Energy Physics - Phenomenology - Abstract
We show that an expansion of nuclear forces about the chiral limit is formally consistent and is equivalent to KSW power counting in the 1S0 channel and Weinberg power counting in the 3S1-3D1 coupled channels. Numerical evidence suggests that this expansion converges. The feasibility of making contact between nuclear physics and lattice-QCD simulations is discussed., Comment: 28 pages LaTex, 28 eps figures
- Published
- 2001
- Full Text
- View/download PDF
42. Annual Report for the Department of Energy: 1999-2000, Nuclear Theory Group at the University of Washington
- Author
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Bulgac, A., Henley, E. M., Miller, G. A., Savage, M. J., and Wilets, L.
- Subjects
Nuclear Theory - Abstract
This document is a summary of the physics research carried out by the Nuclear Theory Group at the University of Washington during the last twelve-month period, 1999-2000., Comment: 33 pages, 5 eps figure, latex
- Published
- 2000
43. Regional Differences in ST-Segment Elevation Myocardial Infarction (STEMI) Treatment and Outcomes in Queensland
- Author
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Savage, M., primary, Murdoch, D., additional, Poon, K., additional, Ranasinghe, I., additional, Walters, D., additional, and Raffel, C., additional
- Published
- 2023
- Full Text
- View/download PDF
44. The successful biological control of Cylindropuntia fulgida var. mamillata (A. Schott ex Engelm.) Backeb. (Cactaceae) (coral or boxing glove cactus) at two field sites in Queensland, Australia
- Author
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Jones, P.K., primary, Day, M.D., additional, McConnachie, A.J., additional, Holtkamp, R.H., additional, Conroy, J., additional, Pidgeon, G., additional, Clark, E., additional, Clark, P., additional, Fletcher, A., additional, and Savage, M., additional
- Published
- 2023
- Full Text
- View/download PDF
45. Design and Comissioning of Vulcan – A testbed for fast Marx generator and vacuum insulator development
- Author
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Hutsel, B. T., primary, Stoltzfus, B. S., additional, Savage, M. E., additional, Johns, O., additional, Breden, E. W., additional, and Sullivan, M. A., additional
- Published
- 2023
- Full Text
- View/download PDF
46. Parental Recall of Birthweight: A Good Proxy for Recorded Birthweight?
- Author
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Walton, K. A., Murray, L. J., Gallagher, A. M., Cran, G. W., Savage, M. J., and Boreham, C.
- Published
- 2000
47. What follow-up interventions, programmes and pathways exist for minor stroke survivors after discharge from the acute setting? A scoping review
- Author
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Crow, J, Savage, M, Gardner, L, Hughes, C, Corbett, C, Wells, M, and Malhotra, P
- Abstract
OBJECTIVE: To identify the breadth and range of follow-up interventions currently provided to people after minor stroke with a focus on the definitions used for minor stroke, intervention components, intervention theory and outcomes used. These findings will inform the development and feasibility testing of a pathway of care. DESIGN: Scoping review. SEARCH STRATEGY: The final search was run in January 2022. Five databases were searched-EMBASE, MEDLINE, CINAHL, British Nursing Index and PsycINFO. Grey literature was also searched. Title and abstract screening and full-text reviews were conducted by two researchers and a third was involved when differences of opinion existed. A bespoke data extraction template was created, refined and then completed. The Template for Intervention Description and Replication (TIDieR) checklist was used to describe interventions. RESULTS: Twenty-five studies, using a range of research methodologies were included in the review. A range of definitions were used for minor stroke. Interventions focused largely on secondary prevention and management of increased risk of further stroke. Fewer focused on the management of hidden impairments experienced after minor stroke. Limited family involvement was reported and collaboration between secondary and primary care was seldom described. The intervention components, content, duration and delivery were varied as were the outcome measures used. CONCLUSION: There is an increasing volume of research exploring how best to provide follow-up care to people after minor stroke. Personalised, holistic and theory-informed interdisciplinary follow-up is needed that balances education and support needs with adjustment to life after stroke.
- Published
- 2023
48. Kaon-Nucleon Couplings for Weak Decays of Hypernuclei
- Author
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Savage, M. J. and Springer, R. P.
- Subjects
High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
We investigate the weak kaon-nucleon (NNK) S-wave and P-wave interactions using heavy baryon chiral perturbation theory. The leading 1-loop SU(3) breaking contributions to the $ppK$, $pnK$, and $nnK$ couplings are computed. We find that they suppress all NNK amplitudes by $30\%$ to $50\%$. The ratio of neutron-induced to proton-induced hypernuclear decay widths is sensitive to such reductions. It has been argued that the discrepancy between the predicted and observed P-wave amplitudes in $\Delta s=1$ hyperon decay results from an accidental cancellation between tree-level amplitudes, and is not a fundamental problem for chiral perturbation theory. Agreement between experimentally determined NNK P-wave amplitudes and our estimates would support this explanation., Comment: uuencoded latex file with figures, 14 pages. A factor of two in the numerical values given for the p-wave amplitudes is corrected
- Published
- 1995
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49. How resilient are southwestern ponderosa pine forests after crown fires?
- Author
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Savage, M and Mast, J N
- Abstract
The exclusion of low-severity surface fire from ponderosa pine (Pinus ponderosa P. & C. Lawson) forests of the Southwest has changed ecosystem structure and function such that severe crown fires are increasingly causing extensive stand mortality. This altered fire regime has resulted from the intersection of natural drought cycles with human activities that have suppressed natural fires for over a century. What is the trajectory of forest recovery after such fires? This study explores the regeneration response of ponderosa pine and other species to crown fires that occurred in the region from the late 1940s to the mid-1970s. We address two main questions: (1) What is the success of ponderosa regeneration and establishment, and (2) Can these sites, burned in stand-destroying fires, be "captured" by other species on the scale of decades? Two main trajectories of recovery were found: (1) establishment of unnaturally dense ponderosa pine stands vulnerable to further crown fire and (2) establishment of nonforested grass or shrub communities.
- Published
- 2005
50. Electromagnetic Moments of the Baryon Decuplet
- Author
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Butler, M. N., Savage, M. J., and Springer, R. P.
- Subjects
High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
We compute the leading contributions to the magnetic dipole and electric quadrupole moments of the baryon decuplet in chiral perturbation theory. The measured value for the magnetic moment of the $\Omega^-$ is used to determine the local counterterm for the magnetic moments. We compare the chiral perturbation theory predictions for the magnetic moments of the decuplet with those of the baryon octet and find reasonable agreement with the predictions of the large--$N_c$ limit of QCD. The leading contribution to the quadrupole moment of the $\Delta$ and other members of the decuplet comes from one--loop graphs. The pionic contribution is shown to be proportional to $I_z$ (and so will not contribute to the quadrupole moment of $I=0$ nuclei), while the contribution from kaons has both isovector and isoscalar components. The chiral logarithmic enhancement of both pion and kaon loops has a coefficient that vanishes in the $SU(6)$ limit. The third allowed moment, the magnetic octupole, is shown to be dominated by a local counterterm with corrections arising at two loops. We briefly mention the strange counterparts of these moments., Comment: Uses harvmac.tex, 15 pages with 3 PostScript figures packed using uufiles. UCSD/PTH 93-22, QUSTH-93-05, Duke-TH-93-56
- Published
- 1993
- Full Text
- View/download PDF
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