480 research outputs found
Sturcture of the Goldstone Bosons
The feasibility of measuring the pion and kaon structure functions has been
investigated. A high luminosity electron-proton collider would make these
measurements feasible. Also, it appears feasible to measure these structure
functions in a nuclear medium. Simulations using the RAPGAP Monte Carlo of a
possible pion structure function measurement are presented.Comment: To appear in the proceedings of the Second Workshop on Physics with
an Electron Polarized Light-Ion Collider, 14-16 Sept 2000, Cambridge, Ma 6
pages, 5 figures, late
SHCal04 Southern Hemisphere Calibration, 0–11.0 cal kyr BP
Recent measurements on dendrochronologically-dated wood from the Southern Hemisphere have shown that there are differences between the structural form of the radiocarbon calibration curves from each hemisphere. Thus, it is desirable, when possible, to use calibration data obtained from secure dendrochronologically-dated wood from the corresponding hemisphere. In this paper, we outline the recent work and point the reader to the internationally recommended data set that should be used for future calibration of Southern Hemisphere ¹⁴C dates
SHCal13 Southern Hemisphere calibration, 0–50,000 years cal BP
The Southern Hemisphere SHCal04 radiocarbon calibration curve has been updated with the addition of new data sets extending measurements to 2145 cal BP and including the ANSTO Younger Dryas Huon pine data set. Outside the range of measured data, the curve is based upon the Northern Hemisphere data sets as presented in IntCal13, with an interhemispheric offset averaging 43 ± 23 yr modeled by an autoregressive process to represent the short-term correlations in the offset
IntCal09 and Marine09 radiocarbon age calibration curves, 0-50,000yeats cal BP
The IntCal04 and Marine04 radiocarbon calibration curves have been updated from 12 cal kBP (cal kBP is here defined as thousands of calibrated years before AD 1950), and extended to 50 cal kBP, utilizing newly available data sets that meet the IntCal Working Group criteria for pristine corals and other carbonates and for quantification of uncertainty in both the 14C and calendar timescales as established in 2002. No change was made to the curves from 0–12 cal kBP. The curves were constructed using a Markov chain Monte Carlo (MCMC) implementation of the random walk model used for IntCal04 and Marine04. The new curves were ratified at the 20th International Radiocarbon Conference in June 2009 and are available in the Supplemental Material at www.radiocarbon.org
NotCal04; comparison/ calibration 14C records 26-50 cal kyr BP
Author Posting. © Arizona Board of Regents on behalf of the University of Arizona, 2004. This article is posted here by permission of Dept. of Geosciences, University of Arizona for personal use, not for redistribution. The definitive version was published in Radiocarbon 46 (2004): 1225-1238.The radiocarbon calibration curve IntCal04 extends back to 26 cal kyr BP. While several high-resolution
records exist beyond this limit, these data sets exhibit discrepancies of up to several millennia. As a result, no calibration curve
for the time range 26–50 cal kyr BP can be recommended as yet, but in this paper the IntCal04 working group compares the
available data sets and offers a discussion of the information that they hold
Luxurious Surfaces: Chinese Decorative Arts from the 15th to the Early 20th Century
Luxurious Surfaces: Chinese Decorative Arts from the Fifteenth to the Early Twentieth Century is a highly anticipated exhibition that highlights student learning in the art history program. The curators, William Caterham ’20, Ashley Jeffords ’20, Merlyn Maldonado Lopez ’22, Sarah Paul ’22, James Raphaelson ’21, Megan Reimer ’22, Shannon Zeltmann ’21 and Tianrun Zhao ’20, are students enrolled in the Art History Method class in Fall 2019. The exhibition examines the quintessential characteristics and the meaning of Chinese decorative arts embedded in the luxurious surfaces of sixteen carefully selected works from Gettysburg College’s Asian Art Collection.https://cupola.gettysburg.edu/artcatalogs/1032/thumbnail.jp
Widely tunable solid-state source of single-photons matching an atomic transition
Hybrid quantum technologies aim to harness the best characteristics of
multiple quantum systems, in a similar fashion that classical computers combine
electronic, photonic, magnetic, and mechanical components. For example, quantum
dots embedded in semiconductor nanowires can produce highly pure,
deterministic, and indistinguishable single-photons with high repetition, while
atomic ensembles offer robust photon storage capabilities and strong optical
nonlinearities that can be controlled with single-photons. However, to
successfully integrate quantum dots with atomic ensembles, one needs to
carefully match the optical frequencies of these two platforms. Here, we
propose and experimentally demonstrate simple, precise, reversible,
broad-range, and local method for controlling the emission frequency of
individual quantum dots embedded in tapered semiconductor nanowires and use it
to interface with an atomic ensemble via single-photons matched to hyperfine
transitions and slow-light regions of the cesium D1-line. Our approach allows
linking together atomic and solid-state quantum systems and can potentially
also be applied to other types of nanowire-embedded solid-state emitters, as
well as to creating devices based on multiple solid-state emitters tuned to
produce indistinguishable photons
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