4,018 research outputs found
Tune Determination of Strongly Coupled Betatron Oscillations in a Fast-Ramping Synchrotron
Tune identification - i.e. attribution of the spectral peak to a particular
normal mode of oscillations - can present a significant difficulty in the
presence of strong transverse coupling when the normal mode with a lower
damping rate dominates spectra of Turn-by-Turn oscillations in both planes. The
introduced earlier phased sum algorithm helped to recover the weaker normal
mode signal from the noise, but by itself proved to be insufficient for
automatic peak identification in the case of close phase advance distribution
in both planes. To resolve this difficulty we modified the algorithm by taking
and analyzing Turn-by-Turn data for two different ramps with the beam
oscillation excited in each plane in turn. Comparison of the relative
amplitudes of Fourier components allows for automatic correct tune
identification. The proposed algorithm was implemented in the Fermilab Booster
B38 console application and successfully used in tune, coupling and
chromaticity measurements.Comment: 3 pp. 3rd International Particle Accelerator Conference (IPAC 2012)
20-25 May 2012, New Orleans, Louisian
Effect of Larval Swimming Duration on Success of Metamorphosis and Size of the Ancestrular Lophophore in \u3cem\u3eBugula neritina\u3c/em\u3e (Bryozoa)
There is a growing realization that events during one portion of an organism\u27s life cycle can have both subtle and dramatic effects on other stages in the life history. Lethal and sublethal effects associated with the duration of larval swimming in marine invertebrates were examined for the bryozoan Bugula neritina. Larvae were kept swimming up to a maximum of 28 h at 20{deg}C by exposure to continuous bright fluorescent illumination. At 4-h intervals, samples of 20-40 larvae were removed from bright illumination and were exposed to seawater containing 10 mM excess KCI, an inducer of metamorphosis in this species. Over the first 12 h of larval swimming, an average of about 90% of the larvae initiated and completed metamorphosis; at 16 h, the percentage of larvae initiating and completing metamorphosis dropped significantly. By 28 h, about half of the larvae were initiating metamorphosis, whereas only one-fifth were completing metamorphosis. Larval swimming duration also significantly affected the duration of metamorphosis. By 30 h of larval swimming, individuals were taking about 25% longer to complete metamorphosis. Compared to ancestrulae that developed from larvae that were induced to metamorphose shortly after the onset of swimming, those that swam for greater than 8 h had significantly smaller lophophores. For example, by 28 h of larval swimming the ancestrular lophophore decreased in height, surface area, and volume by about 25%, 40% and 55%, respectively. This marked decrease in lophophore size may ultimately affect the ability of juveniles to sequester food, compete for space, and attain reproductive maturity. Thus, increasing the duration of larval swimming affects both metamorphosis and the development of postlarval structures, which may ultimately influence colony fitness
Two prehistoric archeological sites in Egyptian Nubia
The Yale University Prehistoric Expedition to Nubia was part of UNESCO\u27S international program to salvage the monuments of Nubia, with the direct aid of the Department of Antiquities of the United Arab Republic…
Broad-band chopper for a CW proton linac at Fermilab
Requirements and technical limitations to the bunch-by-bunch chopper for the
Fermilab Project X are discussed.Comment: 3 pp. Particle Accelerator, 24th Conference (PAC'11) 2011. 28 Mar - 1
Apr 2011. New York, US
Principal Component Analysis of EBT2 Radiochromic Film for Multichannel Film Dosimetry
Wendt III, R. (2014) Principal Component Analysis of EBT2 Radiochromic Film for Multichannel Film Dosimetry. International Journal of Medical Physics, Clinical Engineering and Radiation Oncology, 3, 156-166. doi: 10.4236/ijmpcero.2014.33021.https://openworks.mdanderson.org/mdacc_imgphys_pubs/1002/thumbnail.jp
High Resolution BPM Upgrade for the ATF Damping Ring at KEK
A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility
(ATF) damping ring has been accomplished, carried out by a KEK/FNAL/SLAC
collaboration under the umbrella of the global ILC R&D effort. The upgrade
consists of a high resolution, high reproducibility read-out system, based on
analog and processing, and also implements a new automatic gain error
correction schema. The technical concept and realization as well as results of
beam studies are presented.Comment: 3 pp. 10th European Workshop on Beam Diagnostics and Instrumentation
for Particle Accelerators DIPAC 2011, 16-18 May 2011. Hamburg, German
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