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1. Aminium cation-radical catalysed selective hydration of (E)-aryl enynes

Author: John E. Moses, Andrew S. Barrow, Marie-Claire Giel, William Lewis, and Christopher J. Smedley
Subjects: Tris, chemistry.chemical_classification, Natural product, 010405 organic chemistry, Aryl, Markovnikov's rule, Metals and Alloys, Alkyne, Salt (chemistry), General Chemistry, 010402 general chemistry, Triple bond, 01 natural sciences, Medicinal chemistry, Catalysis, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry.chemical_compound, chemistry, Materials Chemistry, Ceramics and Composites
Abstract: The hydration of carbon–carbon triple bonds is an important and atom economic synthetic transformation. Herein, we report a mild and selective method for the catalytic Markovnikov hydration of (E)-aryl enynes to the corresponding enones, mediated through the bench-stable aminium salt, tris(4-bromophenyl)ammoniumyl hexachloroantimonate (TBPA). The chemoselective and diastereoselective method proceeds under neutral metal-free conditions, delivering excellent product yields from terminal and internal alkyne units. The synthesis of biologically important (E)-3-styrylisocoumarins, including a formal synthesis of the natural product achlisocoumarin III, demonstrates the utility of this novel transformation.
Published: 2021

2. Diversity Oriented Clicking (DOC): Divergent Synthesis of SuFExable Pharmacophores from 2‐Substituted‐Alkynyl‐1‐Sulfonyl Fluoride (SASF) Hubs

Author: Andrew S. Barrow, Alessandra Ottonello, K. Barry Sharpless, Dennis W. Wolan, Gencheng Li, Yunfei Cheng, Marie-Claire Giel, Seiya Kitamura, John E. Moses, Christopher J. Smedley, and Timothy L Gialelis
Subjects: Cycloaddition Reaction, Molecular Structure, Bicyclic molecule, 010405 organic chemistry, Chemistry, General Chemistry, Sulfinic Acids, 010402 general chemistry, 01 natural sciences, Combinatorial chemistry, Article, Catalysis, 0104 chemical sciences, Functional importance, Click chemistry, Click Chemistry, Pharmacophore, Divergent synthesis, Sulfonyl fluoride
Abstract: Diversity Oriented Clicking (DOC) is a unified click-approach for the modular synthesis of lead-like structures through application of the wide family of click transformations. DOC evolved from the concept of achieving "diversity with ease", by combining classic C-C π-bond click chemistry with recent developments in connective SuFEx-technologies. We showcase 2-Substituted-Alkynyl-1-Sulfonyl Fluorides (SASFs) as a new class of connective hub in concert with a diverse selection of click-cycloaddition processes. Through the selective DOC of SASFs with a range of dipoles and cyclic dienes, we report a diverse click-library of 173 unique functional molecules in minimal synthetic steps. The SuFExable library comprises 10 discrete heterocyclic core structures derived from 1,3- and 1,5-dipoles; while reaction with cyclic dienes yields several three-dimensional bicyclic Diels-Alder adducts. Growing the library to 278 discrete compounds through late-stage modification was made possible through SuFEx click derivatization of the pendant sulfonyl fluoride group in 96 well-plates-demonstrating the versatility of the DOC approach for the rapid synthesis of diverse functional structures. Screening for function against MRSA (USA300) revealed several lead hits with improved activity over methicillin.
Published: 2020

3. Diversity Oriented Clicking (DOC): Divergent Synthesis of SuFExable Pharmacophores from 2‐Substituted‐Alkynyl‐1‐Sulfonyl Fluoride (SASF) Hubs

Author: Christopher J. Smedley, Gencheng Li, Andrew S. Barrow, Timothy L. Gialelis, Marie‐Claire Giel, Alessandra Ottonello, Yunfei Cheng, Seiya Kitamura, Dennis W. Wolan, K. Barry Sharpless, and John E. Moses
Subjects: 010405 organic chemistry, General Medicine, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences
Published: 2020

4. The growing applications of SuFEx click chemistry

Author: Jiajia Dong, Suhua Li, Andrew S. Barrow, Qinheng Zheng, John E. Moses, and Christopher J. Smedley
Subjects: Sulfur fluoride, Functional importance, Drug discovery, Chemistry, Click chemistry, Nanotechnology, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 0210 nano-technology, 01 natural sciences, 0104 chemical sciences
Abstract: SuFEx (Sulfur Fluoride Exchange) is a modular, next generation family of click reactions, geared towards the rapid and reliable assembly of functional molecules. This review discusses the growing number of applications of SuFEx, which can be found in nearly all areas of modern chemistry; from drug discovery to materials science.
Published: 2019

5. Paediatric dental-oral medicine clinic: management during COVID 19

Author: R. Cook, Esther Hullah, R. Sanghvi, S. Barrow, D. Siddik, and M. De Souza
Subjects: medicine.medical_specialty, Coronavirus disease 2019 (COVID-19), RD1-811, Recurrent aphthous stomatitis, 01 natural sciences, Systemic therapy, teledentistry, paediatric dentistry, 03 medical and health sciences, Alternative assessment, 0302 clinical medicine, Patient satisfaction, medicine, Dentistry (miscellaneous), Medical history, 030212 general & internal medicine, 0101 mathematics, Teledentistry, business.industry, 010102 general mathematics, RK1-715, covid-19, Family medicine, Dentistry, Periodontics, Surgery, Oral Surgery, business, Oral medicine
Abstract: Introduction: Minimising spread of the COVID-19 infection through reducing face-to-face consults is essential. In doing so, alternative assessment and communication methods for management of patients with oral conditions should be considered. Material and methods: Patients on the waiting list for the joint oral medicine-paediatric dental clinic between March and June 2020 were prioritised based on a criteria including relevant medical history, diagnosis and clinical need and current management − monitoring, topical therapy or systemic therapy. A telephone consult method was chosen to assess and follow up patients and a parental satisfaction questionnaire was conducted following telephone consult. Results: Recurrent aphthous stomatitis (RAS) was the most common diagnosis of patients reviewed on the telephone clinic. Overall, the patient satisfaction questionnaire revealed that 100% of respondents would prefer a telephone consult during COVID-19 rather than face-to-face appointments. 74% opted for a video consult in preference to a telephone consult. Conclusion: This service evaluation has found telephone consults to be a valuable alternative to face-to-face consults in the management of patients with chronic oral mucosal diseases. Telephone consultations have high parental satisfaction and are an effective, convenient method to assess and follow up patients whilst maintaining their safety during the COVID-19 pandemic.
Published: 2021

6. The Lyman Continuum Escape Survey: Connecting Time-Dependent [OIII] and [OII] Line Emission with Lyman Continuum Escape Fraction in Simulations of Galaxy Formation

Author: Kirk S. S. Barrow, A. Saxena, Kimihiko Nakajima, Mengtao Tang, Brant Robertson, Richard S. Ellis, and Daniel P. Stark
Subjects: Physics, 010308 nuclear & particles physics, Continuum (design consultancy), Doubly ionized oxygen, FOS: Physical sciences, Astronomy and Astrophysics, Fraction (chemistry), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Astrophysics - Astrophysics of Galaxies, High time-resolution astrophysics, Emission nebula, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Galaxy formation and evolution, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Line (formation)
Abstract: Escaping Lyman continuum photons from galaxies likely reionized the intergalactic medium at redshifts $z\gtrsim6$. However, the Lyman continuum is not directly observable at these redshifts and secondary indicators of Lyman continuum escape must be used to estimate the budget of ionizing photons. Observationally, at redshifts $z\sim2-3$ where the Lyman continuum is observationally accessible, surveys have established that many objects that show appreciable Lyman continuum escape fractions $f_{esc}$ also show enhanced [OIII]/[OII] (O$_{32}$) emission line ratios. Here, we use radiative transfer analyses of cosmological zoom-in simulations of galaxy formation to study the physical connection between $f_{esc}$ and O$_{32}$. Like the observations, we find that the largest $f_{esc}$ values occur at elevated O$_{32}\sim3-10$ and that the combination of high $f_{esc}$ and low O$_{32}$ is extremely rare. While high $f_{esc}$ and O$_{32}$ often are observable concurrently, the timescales of the physical origin for the processes are very different. Large O$_{32}$ values fluctuate on short ($\sim$1 Myr) timescales during the Wolf-Rayet-powered phase after the formation of star clusters, while channels of low absorption are established over tens of megayears by collections of supernovae. We find that while there is no direct causal relation between $f_{esc}$ and O$_{32}$, high $f_{esc}$ most often occurs after continuous input from star formation-related feedback events that have corresponding excursions to large O$_{32}$ emission. These calculations are in agreement with interpretations of observations that large $f_{esc}$ tends to occur when O$_{32}$ is large, but large O$_{32}$ does not necessarily imply efficient Lyman continuum escape., Comment: 12 pages, 5 figures, submitted to ApJL on September 15, 2020
Published: 2020
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7. Observational signatures of massive black hole formation in the early Universe

Author: Kirk S. S. Barrow, John H. Wise, and Aycin Aykutalp
Subjects: Physics, Supermassive black hole, 010308 nuclear & particles physics, Star formation, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Quasar, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Accretion (astrophysics), Redshift, Galaxy, Black hole, General Relativity and Quantum Cosmology, Spitzer Space Telescope, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: Space telescope observations of massive black holes during their formation may be key to understanding the origin of supermassive black holes and high-redshift quasars. To create diagnostics for their detection and confirmation, we study a simulation of a nascent massive, so-called direct-collapse, black hole that induces a wave of nearby massive metal-free star formation, unique to this seeding scenario and to very high redshifts. Here we describe a series of distinct colors and emission line strengths, dependent on the relative strength of star formation and black hole accretion. We predict that the forthcoming James Webb Space Telescope might be able to detect and distinguish a young galaxy that hosts a direct-collapse black hole in this configuration at redshift 15 with as little as a 20,000-second total exposure time across four filters, critical for constraining supermassive black hole seeding mechanisms and early growth rates. We also find that a massive seed black hole produces strong, H$_2$-dissociating Lyman-Werner radiation., Comment: As submitted on May 30th, 2018. Published in Nature Astronomy on September 10th, 2018
Published: 2018

8. Dynamic Nuclear Polarisation Enhanced Solid-State Nuclear Magnetic Resonance Studies of Surface Modification of γ-Alumina

Author: Subhradip Paul, Marco Mais, Jeremy J. Titman, and Nathan S. Barrow
Subjects: Materials science, Spin polarization, Process Chemistry and Technology, Dynamic nuclear polarisation, Metals and Alloys, 02 engineering and technology, Nuclear magnetic resonance spectroscopy, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Catalysis, NMR spectra database, Unpaired electron, Solid-state nuclear magnetic resonance, Electrochemistry, Surface modification, Physical chemistry, 0210 nano-technology
Abstract: Dynamic nuclear polarization (DNP) gives large (>100-fold) signal enhancements in solid-state NMR spectra via the transfer of spin polarization from unpaired electrons from radicals implanted in the sample. This means that the detailed information about local molecular environment available for bulk samples from solid-state NMR spectroscopy can now be obtained for dilute species, such as sites on the surfaces of catalysts and catalyst supports. In this paper we describe a DNP-enhanced solid-state NMR study of the widely used catalyst gamma-alumina which is often modified at the surface by the incorporation of alkaline earth oxides in order to control the availability of catalytically active penta-coordinate surface Al sites. DNP-enhanced 27Al solid-state NMR allows surface sites in gamma-alumina to be observed and their 27Al NMR parameters measured. In addition changes in the availability of different surface sites can be detected after incorporation of BaO.
Published: 2018

9. Accessibility and Location of Acid Sites in Zeolites as Probed by Fourier Transform Infrared Spectroscopy and Magic Angle Spinning Nuclear Magnetic Resonance

Author: Nathan S. Barrow, Cátia Freitas, and Vladimir L. Zholobenko
Subjects: Materials science, Process Chemistry and Technology, Metals and Alloys, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Nuclear magnetic resonance, Electrochemistry, Magic angle spinning, QD, Fourier transform infrared spectroscopy, 0210 nano-technology
Abstract: The understanding of location and accessibility of zeolite acid sites is a key issue in heterogeneous catalysis. This paper provides a brief overview of Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) characterisation of acidity in zeolites based on the application of test molecules with a diverse range of basicity and kinetic diameters. Many zeolites, including ZSM-5 and BEA, have been characterised by monitoring the interaction between the zeolite acid sites and test molecules, such as 1,3,5-triisopropylbenzene, pyridine and alkylpyridines, to probe the location, accessibility and strength of the Bronsted acid sites. 1,3,5-triisopropylbenzene can be used to distinguish Bronsted acid sites located on the external and internal surface in most medium and large pore channel zeolites. Bronsted acid sites on the external surface of medium pore zeolites can also be quantified using 2,6-di-tert-butyl-pyridine and 2,4,6-trimethylpyridine. It is concluded that using a combination of probe molecules, including co-adsorption experiments, affords differentiation between acid sites located in channels and cavities of different sizes and on the external and internal surfaces of various zeolitic structures.
Published: 2018

10. Environmental drivers of growth and predicted effects of climate change on a commercially important fish, Platycephalus laevigatus

Author: John Ford, Robert W. Day, Joshua S. Barrow, and John R. Morrongiello
Subjects: 0106 biological sciences, 010504 meteorology & atmospheric sciences, Ecology, biology, 010604 marine biology & hydrobiology, Platycephalus laevigatus, Climate change, Aquatic Science, biology.organism_classification, 01 natural sciences, Oceanography, Seagrass, Productivity (ecology), Effects of global warming, Environmental science, Ecosystem, Fisheries management, Flathead, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences
Abstract: Human-driven climate change and habitat modification are negatively impacting coastal ecosystems and the species that reside within them. Uncovering how individuals of key species respond to environmental influences is crucial for effective and responsive coastal resource and fisheries management. Here, using an otolith based analysis, we recreated the growth history of rock flathead Platycephalus laevigatus from Corner Inlet, Victoria, Australia, over a 32 yr timeframe and related growth variation to changes in key environmental variables. Growth increased with higher temperatures during the fish growing season (December-May) and also increased with higher freshwater flow during the period important for seagrass growth (July- February). We hypothesise that fish are responding to enhanced productivity in the seagrass food web, driven by increased nutrient input from freshwater flows. Fish also appear to be responding to higher temperatures via a direct physiological pathway. We then predicted fish growth under 3 plausible climate change scenarios. Growth is predicted to increase across all our projections, because any predicted decrease in river flow will likely be offset by rapid predicted increases in temperature. Our results highlight the value of understanding the drivers of long-term growth variation in harvested fishes as this allows for the prediction of future productivity under a range of environmental and management scenarios.
Published: 2018

11. Carbene Footprinting Reveals Binding Interfaces of a Multimeric Membrane-Spanning Protein

Author: Lucio Manzi, Andrew S. Barrow, Jonathan T. S. Hopper, Renata Kaminska, Colin Kleanthous, Carol V. Robinson, John E. Moses, and Neil J. Oldham
Subjects: 0301 basic medicine, 03 medical and health sciences, 030104 developmental biology, carbene footprinting, integral membrane proteins, protein structures, General Medicine, 010402 general chemistry, 01 natural sciences, protein labelling, mass spectrometry, 0104 chemical sciences
Abstract: © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Mapping the interaction sites between membrane-spanning proteins is a key challenge in structural biology. In this study a carbene-footprinting approach was developed and applied to identify the interfacial sites of a trimeric, integral membrane protein, OmpF, solubilised in micelles. The diazirine-based footprinting probe is effectively sequestered by, and incorporated into, the micelles, thus leading to efficient labelling of the membrane-spanning regions of the protein upon irradiation at 349 nm. Areas associated with protein–protein interactions between the trimer subunits remained unlabelled, thus revealing their location.
Published: 2017

12. Induced metal-free star formation around a massive black hole seed

Author: Jarrett L. Johnson, Aycin Aykutalp, Kirk S. S. Barrow, and John H. Wise
Subjects: Physics, Supermassive black hole, H II region, 010308 nuclear & particles physics, Star formation, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Astrophysics - Astrophysics of Galaxies, Galaxy, Black hole, Supernova, Stars, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Galaxy formation and evolution, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: The direct formation of a massive black hole is a potential seeding mechanism of the earliest observed supermassive black holes. We investigate how the existence of a massive black hole seed impacts the ionization and thermal state of its pre-galactic host halo and subsequent star formation. We show that its X-ray radiation ionizes and heats the medium, enhancing $\rm{H}_2$ formation in shielded regions, within the nuclear region in the span of a million years. The enhanced molecular cooling triggers the formation of a $\sim 10^4~{\rm M}_\odot$ metal-free stellar cluster at a star formation efficiency of $\sim 0.1\%$ in a single event. Star formation occurs near the edges of the H II region that is partially ionized by X-rays, thus the initial size depends on the black hole properties and surrounding environment. The simulated metal-free galaxy has an initial half-light radius of $\sim 10$ pc but expands to $\sim 50$ pc after 10 million years because of the outward velocities of their birth clouds. Supernova feedback then quenches any further star formation for tens of millions of years, allowing the massive black hole to dominate the spectrum once the massive metal-free stars die., Accepted for publication in ApJ Letters, 7 pages, 5 figures
Published: 2019

13. Ion exchange and binding in selenium remediation materials using DNP-enhanced solid-state NMR spectroscopy

Author: Subhradip Paul, Jeremy J. Titman, Javier Torroba, Nathan S. Barrow, and Marco Mais
Subjects: Nuclear and High Energy Physics, Radiation, Ion exchange, 010405 organic chemistry, Inorganic chemistry, Groundwater remediation, chemistry.chemical_element, General Chemistry, 010402 general chemistry, 01 natural sciences, Selenate, 0104 chemical sciences, Ion, NMR spectra database, chemistry.chemical_compound, Solid-state nuclear magnetic resonance, Heteronuclear molecule, chemistry, Instrumentation, Selenium
Abstract: Selenate-loaded selenium water remediation materials based on polymer fibres have been investigated by dynamic nuclear polarization (DNP) enhanced solid-state NMR. For carbon-13 a significant reduction in experiment time is obtained with DNP even when compared with conventional carbon-13 NMR spectra recorded using larger samples. For the selenium remediation materials studied here this reduction allows efficient acquisition of {1H}-77Se heteronuclear correlation spectra which give information about the nature of the binding of the remediated selenate ions with the grafted side chains which provide the required ion exchange functionality.
Published: 2019

14. Increasing early life growth of hatchery-reared freshwater fish can improve stocking outcomes

Author: John D. Koehn, Jian D. L. Yen, John R. Morrongiello, and Joshua S. Barrow
Subjects: 0106 biological sciences, Perch, Ecology, biology, Hatching, 010604 marine biology & hydrobiology, Aquatic Science, Oceanography, biology.organism_classification, 010603 evolutionary biology, 01 natural sciences, Hatchery, medicine.anatomical_structure, Stocking, Animal science, Fish stocking, Freshwater fish, medicine, Macquaria ambigua, Ecology, Evolution, Behavior and Systematics, Otolith
Abstract: Stock enhancement is an important tool used to rebuild depleted fish populations or enhance recreational fishing. Hatchery-reared individuals can express trait differences, such as growth, which may affect later survival. However, there is little understanding of how early life growth variation affects stocking success. We examined early life growth of golden perch Macquaria ambigua and assessed how growth within hatcheries affects the survival of stocked fish. We measured daily otolith increment widths at 10, 20 and 30 days after hatching, but before stocking into lakes in south-eastern Australia. Mean growth decreased with age, but variation in growth increased. We then compared the early life growth of these individuals to those recaptured after 2 years at liberty (age-2+). Faster individual growth between 20 and 30 days was positively correlated with increased length at stocking. Mean growth between 20 and 30 days of age-2+ fish was higher than that of young-of-year fish, but among-individual variation in growth did not differ between the two groups. These results suggest that individuals with fast hatchery growth have increased survival to 2 years. We propose that enhancing growth within hatcheries may increase the survival of stocked fish, and thus the cost-effectiveness of fish stocking.
Published: 2021

15. Synthesis of Sulfonyl Azides via Lewis Base Activation of Sulfonyl Fluorides and Trimethylsilyl Azide

Author: Andrew S. Barrow and John E. Moses
Subjects: Sulfonyl, chemistry.chemical_classification, Primary (chemistry), 010405 organic chemistry, Organic Chemistry, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Trimethylsilyl azide, Organic chemistry, Diazo, Lewis acids and bases, Sulfonyl fluoride
Abstract: A protocol for the efficient conversion of sulfonyl fluorides into sulfonyl azides through Lewis base activation is described. The in situ generated sulfonyl azides are efficient diazo-transfer agents, affording diazo compounds and primary azides in excellent yields.
Published: 2016

16. Surface Selective 1H and 27Al MAS NMR Observations of Strontium Oxide Doped γ-Alumina

Author: Nathan S. Barrow, Andrew Scullard, and Nicola Collis
Subjects: Materials science, Process Chemistry and Technology, Doping, Metals and Alloys, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, γ alumina, chemistry.chemical_compound, chemistry, Electrochemistry, Physical chemistry, 0210 nano-technology, Strontium oxide
Abstract: High-surface area γ-alumina is industrially used as a catalyst support. Catalytically active elements are doped onto the support, where they can bind to AlO4, AlO5 or AlO6 sites on the surface. Pretreating the surface with alkaline earth oxides can alter the availability of these surface sites, hence affecting the catalytic activity. The surface binding sites of strontium oxide (SrO) on γ-alumina were previously unknown. Direct 27Al magic angle spinning nuclear magnetic resonance (MAS NMR) could not detect AlO5 sites at 9.4 T, so 1H‐27Al cross-polarisation (CP) MAS NMR was used to preferentially select the surface environment signals. We directly observed the three surface environments on dehydrated γ-alumina as a function of SrO impregnation up to 4 wt% SrO. We found that Sr2+ preferentially binds to AlO5 and AlO6 surface sites. 1H MAS NMR revealed SrO impregnation causes a reduction in the terminal (−0.3 ppm) and bridging (2.2 ppm) hydroxyl environments, as well as the promotion of a new peak in between these sites, at 0.5 ppm. By using 1H‐27Al CP/MAS NMR the relative proportions of surface sites on γ-alumina can be determined, allowing an optimal level of SrO doping that can saturate all the AlO5 sites. Importantly, this provides a method of subsequently depositing catalytically active elements on just the AlO4 or AlO6 sites, which can provide a different catalytic activity or stability compared to the AlO5 binding site.
Published: 2016

17. Biomimetic Approaches Towards The Synthesis of Complex Dimeric Natural Products

Author: Andrew S. Barrow, Christian Spiteri, John E. Moses, Paul A. Stanley, Jonathan C. Moore, and Pallavi Sharma
Subjects: Pharmacology, Biological Products, Natural product, Molecular Structure, 010405 organic chemistry, Stereochemistry, Chemistry Techniques, Synthetic, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Aldol reaction, Biomimetics, Drug Discovery, Humans, Dimerization, Conjugate
Abstract: We present a selection of elegant and diverse biomimetic syntheses of complex natural product dimers. The dimerisation pathways discussed encompass the most prevalent strategies, including: Diels-Alder, Aldol, Mannich, conjugate addition, oxidative, radical and photochemical approaches; each underpinned through rational biosynthetic speculation.
Published: 2016

18. Modification of Carbon Fibre Surfaces by Sulfur-Fluoride Exchange Click Chemistry

Author: Andrew S. Barrow, Chantelle L. Arnold, Daniel J. Eyckens, Paul S. Francis, Luke C. Henderson, Egan H. Doeven, Anders J. Barlow, James D. Randall, Filip Stojcevski, and John E. Moses
Subjects: Silylation, Aryl, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Redox, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Chemical engineering, Click chemistry, Moiety, Surface modification, Fiber, Physical and Theoretical Chemistry, 0210 nano-technology, Fluoride
Abstract: Technologies that enable surface modification are in high demand and are critical for the implementation of new functional materials and devices. Here, we describe the first modification of a carbon surface (in this case carbon fiber) using the sulfur-fluoride exchange (SuFEx) reaction. The parent sulfur (VI) fluoride moiety can be installed directly to the surface via electrochemical deposition of the fluorosulfate phenyldiazonium tetrafluoroborate salt, or by 'SuFExing' a phenol on the carbon surface followed by treatment of the material with SO2 F2 ; similar to a 'graft to' or 'graft from' functionalization approach. We demonstrate that these SuFEx-able surfaces readily undergo exchange with aryl silyl ethers, and that the subsequent sulfate linkages are themselves stable under electrochemical redox conditions. Finally, we showcase the utility of the SuFEx chemistry by installing a pendant amino group to the fiber surface resulting in interfacial shear strength improvements of up to 130 % in epoxy resin.
Published: 2018

19. Sustainable Syntheses of (−)-Jerantinines A & E and Structural Characterisation of the Jerantinine-Tubulin Complex at the Colchicine Binding Site

Author: Mohannad E. Qazzaz, Andrew S. Barrow, Hendrika M. Duivenvoorden, John E. Moses, Tracey D. Bradshaw, Michel O. Steinmetz, Andrea E. Prota, Paul A. Stanley, Kuan-Hon Lim, Belinda S. Parker, Natacha Olieric, Hilary M. Collins, Toh-Seok Kam, Brian J. Smith, Harry Eastman, and Christopher J. Smedley
Subjects: Models, Molecular, Tabernaemontana, Stereochemistry, Science, Crystallography, X-Ray, 010402 general chemistry, Microtubules, 01 natural sciences, Article, Indole Alkaloids, Broad spectrum, Tubulin, Microtubule, Cell Line, Tumor, Colchicine binding, Humans, Voacanga, Mode of action, Tabernaemontana corymbosa, Indole test, Tubulin complex, Multidisciplinary, biology, 010405 organic chemistry, Chemistry, Endangered Species, Green Chemistry Technology, 15. Life on land, biology.organism_classification, Antineoplastic Agents, Phytogenic, Tubulin Modulators, 0104 chemical sciences, Seeds, Quinolines, Aspidosperma, Medicine, Drug Screening Assays, Antitumor, Colchicine
Abstract: The jerantinine family of Aspidosperma indole alkaloids from Tabernaemontana corymbosa are potent microtubule-targeting agents with broad spectrum anticancer activity. The natural supply of these precious metabolites has been significantly disrupted due to the inclusion of T. corymbosa on the endangered list of threatened species by the International Union for Conservation of Nature. This report describes the asymmetric syntheses of (−)-jerantinines A and E from sustainably sourced (−)-tabersonine, using a straight-forward and robust biomimetic approach. Biological investigations of synthetic (−)-jerantinine A, along with molecular modelling and X-ray crystallography studies of the tubulin—(−)-jerantinine B acetate complex, advocate an anticancer mode of action of the jerantinines operating via microtubule disruption resulting from binding at the colchicine site. This work lays the foundation for accessing useful quantities of enantiomerically pure jerantinine alkaloids for future development.
Published: 2018

20. 1-Bromoethene-1-sulfonyl fluoride (BESF) is another good connective hub for SuFEx click chemistry

Author: John E. Moses, Christopher J. Smedley, Andrew Molino, David J. D. Wilson, Andrew S. Barrow, and Marie-Claire Giel
Subjects: Silylation, 010405 organic chemistry, Aryl, Metals and Alloys, Bromoethene, General Chemistry, 010402 general chemistry, 01 natural sciences, Combinatorial chemistry, Catalysis, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry.chemical_compound, Sulfonate, chemistry, Materials Chemistry, Ceramics and Composites, Click chemistry, Fluoride, Sulfonyl fluoride
Abstract: We demonstrate 1,2-dibromoethane-1-sulfonyl fluoride (DESF) as a bench-stable and readily accessible precursor to the robust SuFEx connector, 1-bromoethene-1-sulfonyl fluoride (BESF). The in situ generation of BESF from DESF opens up several new reaction profiles, including application in the syntheses of unprecedented 3-substituted isoxazole-5-sulfonyl fluorides, 1-substituted-1H-1,2,3-triazole-4-sulfonyl fluorides, 2-amino-1-bromoethane-1-sulfonyl fluorides and 4-bromo-β-sultams in good to excellent yields. These new modules comprise a pendant sulfonyl fluoride handle, which further undergoes facile and selective SuFEx reactions with a selection of aryl silyl ethers to generate stable and useful sulfonate connections.
Published: 2018

21. Using neutrons, X-rays and nuclear magnetism to determine the role of transition metal oxide inclusions on both glass structure and stability in automotive glass enamels

Author: Patricia Sutton, Simon R. Johnson, Daniel T. Bowron, Nathan S. Barrow, and Jonathan Booth
Subjects: Materials science, Borosilicate glass, Doping, Iron oxide, Oxide, General Physics and Astronomy, chemistry.chemical_element, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Bismuth, chemistry.chemical_compound, chemistry, Chemical engineering, Transition metal, Phase (matter), Physical and Theoretical Chemistry, 0210 nano-technology, Boron
Abstract: Low levels of transition metal oxides in alkali borosilicate glass systems can drastically influence crystallisation and phase separation properties. We investigated the non-monotonic effect of manganese doping on suppressing crystallisation, and the influence on optical properties by iron oxide doping, in terms of local atomic structure. Structural models based on empirical potential structure refinement were generated from neutron and X-ray scattering data, and compared against multinuclear solid-state NMR. This revealed that a 2.5% manganese doping had a disruptive effect on the entire glass network, supressing crystallisation of an undesired bismuth silicate phase, and that iron species preferentially locate near borate tetrahedra. Preventing phase separation and controlling crystallisation behaviour of glass are critical to the ultimate properties of automotive glass enamels.
Published: 2018

22. Sulfur-Fluoride Exchange (SuFEx)-Mediated Synthesis of Sterically Hindered and Electron-Deficient Secondary and Tertiary Amides via Acyl Fluoride Intermediates

Author: John E. Moses, Andrew S. Barrow, Pallavi Sharma, Christian Spiteri, Marie-Claire Giel, and Christopher J. Smedley
Subjects: Steric effects, chemistry.chemical_classification, 010405 organic chemistry, Biomolecule, Organic Chemistry, General Chemistry, 010402 general chemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Acylation, chemistry.chemical_compound, chemistry, Amide, Functional group, Click chemistry, Peptide bond, Organic chemistry, Fluoride
Abstract: Amide bond formation is one of the most executed reactions in chemistry and biology. This is largely due to the ubiquity of the amide functional group in biological molecules, natural products and pharmaceutically important drugs. We report here the development of "SuFExAmide": a new sulfur-fluoride exchange (SuFEx) click chemistry based protocol for the efficient amidation of carboxylic acids via acyl fluoride intermediates. We have developed benzene-1,3-disulfonyl fluoride as a cost effective, powerful and versatile coupling agent, which delivers challenging secondary and tertiary amides in excellent yields from sterically hindered and electron-deficient amines. The straightforward method offers significant benefits over existing protocols in terms of substrate scope, efficiency and ease of operation and is demonstrated by the synthesis of 44 amides, including GNF6702, an antiprotozoal drug candidate. In the majority of cases, the amide products are obtained in high yield without the need for excess reagents or chromatographic purification.
Published: 2017

23. First Light II: Emission Line Extinction, Population III Stars, and X-ray Binaries

Author: John H. Wise, Hao Xu, Kirk S. S. Barrow, Brian W. O'Shea, Aycin Aykutalp, and Michael L. Norman
Subjects: Stellar population, Metallicity, Extinction (astronomy), Population, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 0103 physical sciences, Emission spectrum, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Physics, High Energy Astrophysical Phenomena (astro-ph.HE), education.field_of_study, 010308 nuclear & particles physics, Astronomy, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Redshift, Galaxy, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: We produce synthetic spectra and observations for metal-free stellar populations and high mass X-ray binaries in the Renaissance Simulations at a redshift of 15. We extend our methodology from the first paper in the series by modelling the production and extinction of emission lines throughout a dusty and metal-enriched interstellar and circum-galactic media extracted from the simulation, using a Monte Carlo calculation. To capture the impact of high-energy photons, we include all frequencies from hard X-ray to far infrared with enough frequency resolution to discern line emission and absorption profiles. The most common lines in our sample in order of their rate of occurrence are Ly$\alpha$, the C IV $\lambda\lambda1548,1551$ doublet, H-$\alpha$, and the Ca II $\lambda\lambda\lambda8498,8542,8662$ triplet. The best scenario for a direct observation of a metal-free stellar population is a merger between two Population III galaxies. In mergers between metal-enriched and metal-free stellar populations, some characteristics may be inferred indirectly. Single Population III galaxies are too dim to be observed photometrically at $z = 15$. Ly$\alpha$ emission is discernible by $JWST$ as an increase in $\rm{J_{200w} - J_{277w}}$ colour off the intrinsic stellar tracks. Observations of metal-free stars will be difficult, though not impossible, with the next generation of space telescopes., Comment: 19 pages, 14 figures, 1 table, submitted to MNRAS September 11, 2017, Published November 17, 2017
Published: 2017
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24. First Light: exploring the Spectra of High-Redshift Galaxies in the Renaissance Simulations

Author: John H. Wise, Michael L. Norman, Kirk S. S. Barrow, Brian W. O'Shea, and Hao Xu
Subjects: Physics, Stellar mass, 010308 nuclear & particles physics, Hubble Deep Field, Metallicity, Extinction (astronomy), Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Galaxy, Redshift, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Emission spectrum, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, 010303 astronomy & astrophysics, Reionization, Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics::Galaxy Astrophysics
Abstract: We present synthetic observations for the first generations of galaxies in the Universe and make predictions for future deep field observations for redshifts greater than 6. Due to the strong impact of nebular emission lines and the relatively compact scale of HII regions, high resolution cosmological simulations and a robust suite of analysis tools are required to properly simulate spectra. We created a software pipeline consisting of FSPS, Hyperion, Cloudy and our own tools to generate synthetic IR observations from a fully three-dimensional arrangement of gas, dust, and stars. Our prescription allows us to include emission lines for a complete chemical network and tackle the effect of dust extinction and scattering in the various lines of sight. We provide spectra, 2-D binned photon imagery for both HST and JWST IR filters, luminosity relationships, and emission line strengths for a large sample of high redshift galaxies in the Renaissance Simulations. Our resulting synthetic spectra show high variability between galactic halos with a strong dependence on stellar mass, metallicity, gas mass fraction, and formation history. Halos with the lowest stellar mass have the greatest variability in [OIII]/H$\beta$, [OIII] and CIII] while halos with higher masses are seen to show consistency in their spectra and [OIII] equivalent widths (EW) between 1\AA\ and 10\AA. Viewing angle accounted for three-fold difference in flux due to the presence of ionized gas channels in a halo. Furthermore, JWST color plots show a discernible relationship between redshift, color, and mean stellar age., Comment: Version 2. 17 pages, 14 figures. Published May 15, 2017
Published: 2017
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25. Modification of Carbon Fibre Surfaces by Sulfur-Fluoride Exchange Click Chemistry

Author: Anders J. Barlow, Filip Stojcevski, James D. Randall, Andrew S. Barrow, Egan H. Doeven, Daniel J. Eyckens, Paul S. Francis, Luke C. Henderson, John E. Moses, and Chantelle L. Arnold
Subjects: Sulfur fluoride, Chemical engineering, Chemistry, Click chemistry, Cover (algebra), 02 engineering and technology, Physical and Theoretical Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 0210 nano-technology, 01 natural sciences, Atomic and Molecular Physics, and Optics, 0104 chemical sciences
Published: 2018

26. 1H and 13C solution- and solid-state NMR investigation into wax products from the Fischer–Tropsch process

Author: Mark E. Smith, Peter Ellis, Peter Trenton Bishop, Nathan S. Barrow, Alan Wong, R. J. Speight, and Jonathan P. Rourke
Subjects: chemistry.chemical_classification, Nuclear and High Energy Physics, Wax, Radiation, 010405 organic chemistry, Chemistry, chemistry.chemical_element, Fischer–Tropsch process, General Chemistry, Rhenium, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Catalysis, NMR spectra database, Hydrocarbon, Solid-state nuclear magnetic resonance, visual_art, visual_art.visual_art_medium, Magic angle spinning, Physical chemistry, Organic chemistry, QD, Instrumentation
Abstract: (1)H and (13)C solid- and solution-state NMR have been used to characterise waxes produced in the Fischer-Tropsch reaction, using Co-based catalysts either unpromoted or promoted with approximately 1 wt% of either cerium or rhenium. The aim was to measure average structural information at the submolecular level of the hydrocarbon waxes produced, along with identification of the minor products, such as oxygenates and olefins, which are typically observed in these waxes. A parameter of key interest is the average number of carbon atoms within the hydrocarbon chain (N(C)). A wax prepared using an unpromoted Co/Al(2)O(3) catalyst had N(C)similar to 20, whilst waxes made using rhenium- or cerium-promoted Co/Al(2)O(3) catalysts were found to have N(C)similar to 21. All three samples contained small amounts of oxygenates and alkenes. The subtle differences found in the waxes, in particular the minor species produced, demonstrate that the different promoters have different effects during the reaction, with the Re-promoted catalyst producing the fewest by-products. It is shown in (13)C solid-state NMR spectra that for that for longer chain (compared to the lengths of chain in previous studies) waxes that the lack of resolution and the complexities added by the differential cross-polarisation (CP) dynamics mean that it is difficult to accurately determine N(C) from this approach. However the N(C) determined by (13)C CP magic angle spinning NMR is broadly consistent with the more accurate solution approaches used and suggest that the wax characteristics do not change in solution. On this basis an alternative approach for determining N(C) is suggested based on (1)H solution state NMR that provides a higher degree of accuracy of the chain length as well as information on the minor constituents.
Published: 2011

27. Moments of the spin structure functions g1p and g1d for 0.05<Q2<3.0 GeV2

Author: R. A. Schumacher, G. V. O'Rielly, C. D. Keith, Cynthia Marie Hadjidakis, Z. W. Zhao, Chaden Djalali, D. G. Jenkins, Michael Dugger, S. Tkachenko, H. O. Funsten, A. I. Ostrovidov, A. C S Lima, S. Bültmann, L. Morand, M. R. Niroula, T. A. Forest, D. G. Ireland, G. Asryan, Volker D. Burkert, A. S. Biselli, J. Pierce, Elton Smith, M. J. Amaryan, M. MacCormick, O. P. Dzyubak, R. A. Niyazov, I. Hleiqawi, S. L. Careccia, Larry Weinstein, Avraham Klein, E. Golovatch, H. G. Juengst, K. Moriya, Daniel S. Carman, J. Kuhn, Philip L. Cole, S. McAleer, H. Hakobyan, S. Anefalos Pereira, P. D. Rubin, L. Blaszczyk, P. Corvisiero, Y. G. Sharabian, A. Fradi, L. Cheng, G. Audit, A.V. Stavinsky, C. E. Hyde-Wright, F. Sabatié, Nikolay Shvedunov, D. Heddle, P. Stoler, Friedrich Klein, J. P. Cummings, R. De Vita, N. Markov, V. Sapunenko, C. Salgado, Dinko Pocanic, L. Elouadrhiri, N. Kalantarians, S. Stepanyan, K. S. Egiyan, R. C. Minehart, C. A. Meyer, J. Ball, M. Taiuti, S. E. Kuhn, I. I. Strakovsky, M. Bektasoglu, M. Kossov, K. Mikhailov, K.H. Hicks, R. J. Feuerbach, G. V. Fedotov, M. Nozar, A. Deur, I. Popa, V. Crede, J. W. Price, Shifeng Chen, M. Anghinolfi, Laird Kramer, D. P. Watts, H. Egiyan, G. Gavalian, John A. Mueller, L. Casey, B. L. Berman, P. Mattione, B. B. Niczyporuk, G. Rosner, N. Benmouna, N. Pivnyuk, Kwangsoo Kim, J. T. Goetz, M. Mirazita, G. Riccardi, J. R. Calarco, R. A. Miskimen, B. A. Raue, B. McKinnon, W. J. Briscoe, L. M. Qin, R. G. Fersh, P. Eugenio, J. Langheinrich, C. Butuceanu, C. Hanretty, S. S. Stepanyan, E. Pasyuk, S. A. Philips, M. Ripani, G. Ricco, S. A. Morrow, C. Paterson, Y. Ilieva, Michael Vineyard, Victor Mokeev, M. Klusman, B. M. Preedom, D. Branford, P. Collins, B. Moreno, J. R. Johnstone, Lorenzo Zana, J. P. Santoro, Tsutomu Mibe, Gerald Feldman, J. M. Laget, L. Todor, D. Protopopescu, K. L. Giovanetti, S. V. Kuleshov, C. Marchand, S. Pozdniakov, M. Garçon, M. L. Seely, Ji Li, D. J. Tedeschi, G. E. Dodge, H. Y. Lu, J. Lachniet, I. Bedlinskiy, Marco A. Huertas, A. Tkabladze, M. D. Mestayer, E. L. Isupov, P. V. Degtyarenko, D. Rowntree, K. Livingston, Michael L. Williams, M. Holtrop, R. Suleiman, V. Kuznetsov, D. S. Dale, J. Zhang, S. Boiarinov, D. I. Sober, Gerard Gilfoyle, F. X. Girod, G. S. Mutchler, N. A. Baltzell, I. Niculescu, D. Sokhan, J. Salamanca, K. A. Griffioen, D. Lawrence, M. Guillo, N. Guler, R. De Masi, L. El Fassi, J. W C McNabb, Sylvain Bouchigny, H. Denizli, M. Guidal, M. Battaglieri, J. Hardie, S. Strauch, J. D. Kellie, Z. Krahn, R. Nasseripour, S. Barrow, P. Rossi, R. Dickson, N. Baillie, D. Doughty, V. Gyurjyan, R. Bradford, K. Lukashin, B. E. Stokes, G. S. Adams, H. Bagdasaryan, P. Nadel-Turonski, A. V. Skabelin, K. Joo, A. Cazes, S. Procureur, Maryam Moteabbed, Bernhard Mecking, K. V. Dharmawardane, L. Guo, M. Ungaro, D. P. Weygand, E. Wolin, N. Hassall, M. Bellis, D. G. Crabb, J. Yun, D. Cords, P. Bosted, A. Yegneswaran, N. Dashyan, Y. Prok, Barry Ritchie, E. De Sanctis, H. S. Jo, S. Niccolai, R. Fatemi, A. V. Vlassov, P. Coltharp, R. W. Gothe, M. M. Ito, K. Y. Kim, M. Osipenko, K. Beard, L. C. Smith, E. Munevar, Kalvir S. Dhuga, B. S. Ishkhanov, O. Pogorelko, M. Khandaker, B. Zhao, F. W. Hersman, W. Kim, G. Niculescu, N. Gevorgyan, L. C. Dennis, B. E. Bonner, H. Avakian, D. Sharov, S. A. Dytman, W. K. Brooks, K. Park, V. P. Kubarovsky, J. Shaw, Michael Wood, K. Hafidi, and V. S. Serov
Subjects: Physics, Nuclear and High Energy Physics, Chiral perturbation theory, Heavy baryon chiral perturbation theory, Proton, 010308 nuclear & particles physics, Nuclear Theory, Hadron, 01 natural sciences, Baryon, Nuclear physics, Polarizability, 0103 physical sciences, Sum rule in quantum mechanics, Nuclear Experiment, 010306 general physics, Nucleon
Abstract: The spin structure functions g 1 for the proton and the deuteron have been measured over a wide kinematic range in x and Q 2 using 1.6 and 5.7 GeV longitudinally polarized electrons incident upon polarized NH3 and ND3 targets at Jefferson Lab. Scattered electrons were detected in the CEBAF Large Acceptance Spectrometer, for 0.05 Q 2 5 GeV 2 and W 3 GeV . The first moments of g 1 for the proton and deuteron are presented – both have a negative slope at low Q 2 , as predicted by the extended Gerasimov–Drell–Hearn sum rule. The first extraction of the generalized forward spin polarizability of the proton γ 0 p is also reported. This quantity shows strong Q 2 dependence at low Q 2 . Our analysis of the Q 2 evolution of the first moment of g 1 shows agreement in leading order with Heavy Baryon Chiral Perturbation Theory. However, a significant discrepancy is observed between the γ 0 p data and Chiral Perturbation calculations for γ 0 p , even at the lowest Q 2 .
Published: 2009

28. Measurement of the x- and Q2-dependence of the asymmetry A1 on the nucleon

Author: L. Elouadrhiri, R. A. Miskimen, M. Khandaker, B. McKinnon, G. Rosner, I. I. Strakovsky, R. W. Gothe, M. Bellis, D. Branford, P. Rossi, K. Y. Kim, A. Deur, S. V. Kuleshov, H. G. Juengst, K. S. Egiyan, P. V. Degtyarenko, P. Dragovitsch, M. Battaglieri, M. Nozar, D. J. Tedeschi, M. Taiuti, I. Bedlinskiy, L. Todor, J. P. Cummings, D. Doughty, F. X. Girod, S. Niccolai, D. Protopopescu, Laird Kramer, J. Hardie, V. Gyurjyan, R. De Masi, B. E. Stokes, F. Ronchetti, R. A. Schumacher, P. Corvisiero, V. P. Kubarovsky, G. S. Adams, D. Heddle, Brian Raue, M. Mirazita, G. Ricco, Dinko Pocanic, L. C. Smith, S. Tkachenko, R. Bradford, K. Lukashin, Y. G. Sharabian, O. Pogorelko, E. Wolin, S. McAleer, S. E. Kuhn, V. Sapunenko, B. S. Ishkhanov, Ji Li, Jean Laget, N. Benmouna, N. Pivnyuk, Rakhsha Nasseripour, B. Carnahan, L. C. Dennis, B. E. Bonner, M. Guillo, C. Tur, J. Napolitano, A. I. Ostrovidov, R. Fatemi, A. C S Lima, Gerard Gilfoyle, D. Cords, Marco A. Huertas, H. Avakian, E. S. Smith, K. Park, A. V. Vlassov, D. G. Ireland, M. R. Niroula, V. Batourine, B. Zhao, Y. Ilieva, E. L. Isupov, R. Suleiman, I. Hleiqawi, L. Guo, S. Bültmann, Volker D. Burkert, A. S. Biselli, H. S. Jo, E. Golovatch, Michael L. Williams, P. Bosted, S. L. Careccia, James Mueller, G. S. Mutchler, R. DeVita, M. Ripani, S. A. Morrow, Atilla Gonenc, M. MacCormick, C. Djalali, F. W. Hersman, T. A. Forest, M. Anghinolfi, P. D. Rubin, S. Stepanyan, A. Cazes, G. Gavalian, J. W. Price, S. Boiarinov, Maryam Moteabbed, B. M. Preedom, N. A. Baltzell, Sylvain Bouchigny, J. P. Ball, Y. Prok, K. L. Giovanetti, Michael Dugger, A. Yegneswaran, Shifeng Chen, K. V. Dharmawardane, J. Pierce, M. Kossov, Avraham Klein, Jens H. Kuhn, A. Stavinsky, Larry Weinstein, P. Ambrozewicz, E. Pasyuk, L. M. Qin, K. A. Griffioen, H. O. Funsten, P. Coltharp, U. Thoma, C. Keith, Lorenzo Zana, D. P. Weygand, S. A. Dytman, Hall Crannell, M. M. Ito, N. Baillie, J. T. Goetz, G. V. O'Rielly, C. Paterson, M. Klusman, K. Livingston, V. Crede, Z. W. Zhao, Frank Klein, D. G. Crabb, J. R. Calarco, S. Strauch, D. G. Jenkins, C. Salgado, J. D. Kellie, G. E. Dodge, S. Pozdniakov, N. Guler, J. W C McNabb, M. D. Mestayer, I. Niculescu, Nikolay Shvedunov, D. Lawrence, M. Guidal, D. I. Sober, S. S. Stepanyan, M. Osipenko, S. Barrow, F. Sabatié, Michael Vineyard, K. Beard, M. Garçon, B. Mecking, G. Riccardi, J. Shaw, C. Butuceanu, Michael Wood, W. K. Brooks, K. Hafidi, V. S. Serov, Victor Mokeev, M. Ungaro, K. Joo, J. Yun, J. P. Santoro, Roy Thompson, K. Kim, J. J. Manak, P. Eugenio, J. Zhang, H. Bagdasaryan, P. Collins, Daniel S. Carman, C. Hadjidakis, C. E. Hyde-Wright, M. Bektasoglu, J. Langheinrich, S. A. Philips, G. Niculescu, M. Holtrop, Hong Lu, P. L. Cole, P. Nadel-Turonski, Tsutomu Mibe, B. B. Niczyporuk, J. Lachniet, A. Tkabladze, D. Rowntree, R. S. Hakobyan, J. Donnelly, O. P. Dzyubak, R. A. Niyazov, R. J. Feuerbach, L. Morand, P. Stoler, E. De Sanctis, K. Hicks, W. Kim, Susan Taylor, K. Mikhailov, H. Egiyan, N. Markov, Barry Ritchie, G. Asryan, H. Denizli, A. V. Skabelin, R. C. Minehart, C. A. Meyer, G. V. Fedotov, and E. Polli
Subjects: Quark, Physics, Nuclear and High Energy Physics, Particle physics, Proton, 010308 nuclear & particles physics, media_common.quotation_subject, Momentum transfer, Quark model, Parton, 01 natural sciences, Asymmetry, Nuclear physics, 0103 physical sciences, Invariant mass, 010306 general physics, Nucleon, media_common
Abstract: We report results for the virtual photon asymmetry A{sub 1} on the nucleon from new Jefferson Lab measurements. The experiment, which used the CEBAF Large Acceptance Spectrometer and longitudinally polarized proton ({sup 15}NH{sub 3}) and deuteron ({sup 15}ND{sub 3}) targets, collected data with a longitudinally polarized electron beam at energies between 1.6 GeV and 5.7 GeV. In the present paper, we concentrate on our results for A{sub 1}(x,Q{sup 2}) and the related ratio g{sub 1}/F{sub 1}(x,Q{sup 2}) in the resonance and the deep inelastic regions for our lowest and highest beam energies, covering a range in momentum transfer Q{sup 2} from 0.05 to 5.0 GeV{sup 2} and in final-state invariant mass W up to about 3 GeV. Our data show detailed structure in the resonance region, which leads to a strong Q{sup 2}--dependence of A{sub 1}(x,Q{sup 2}) for W below 2 GeV. At higher W, a smooth approach to the scaling limit, established by earlier experiments, can be seen, but A{sub 1}(x,Q{sup 2}) is not strictly Q{sup 2}--independent. We add significantly to the world data set at high x, up to x = 0.6. Our data exceed the SU(6)-symmetric quark model expectation for both the proton and the deuteron whilemore » being consistent with a negative d-quark polarization up to our highest x. This data set should improve next-to-leading order (NLO) pQCD fits of the parton polarization distributions.« less
Published: 2006

29. Observation of a Coherence Length Effect in Exclusiveρ0Electroproduction

Author: K. Ackerstaff, A. Airapetian, N. Akopov, I. Akushevich, M. Amarian, E. C. Aschenauer, H. Avakian, R. Avakian, A. Avetissian, B. Bains, S. Barrow, C. Baumgarten, M. Beckmann, St. Belostotski, J. E. Belz, Th. Benisch, S. Bernreuther, N. Bianchi, S. Blanchard, J. Blouw, H. Böttcher, A. Borissov, J. Brack, S. Brauksiepe, B. Braun, B. Bray, St. Brons, W. Brückner, A. Brüll, E. E. W. Bruins, H. J. Bulten, R. V. Cadman, G. P. Capitani, P. Carter, P. Chumney, E. Cisbani, G. R. Court, P. F. Dalpiaz, P. P. J. Delheij, E. De Sanctis, D. De Schepper, E. Devitsin, P. K. A. de Witt Huberts, P. Di Nezza, M. Düren, A. Dvoredsky, G. Elbakian, J. Ely, J. Emerson, A. Fantoni, A. Fechtchenko, M. Ferstl, D. Fick, K. Fiedler, B. W. Filippone, H. Fischer, H. T. Fortune, B. Fox, S. Frabetti, J. Franz, S. Frullani, M.-A. Funk, N. D. Gagunashvili, P. Galumian, H. Gao, Y. Gärber, F. Garibaldi, G. Gavrilov, P. Geiger, V. Gharibyan, V. Giordjian, A. Golendukhin, G. Graw, O. Grebeniouk, P. W. Green, L. G. Greeniaus, C. Grosshauser, M. G. Guidal, A. Gute, V. Gyurjyan, J. P. Haas, W. Haeberli, J.-O. Hansen, D. Hasch, O. Häusser, F. H. Heinsius, R. S. Henderson, Th. Henkes, M. Henoch, R. Hertenberger, Y. Holler, R. J. Holt, W. Hoprich, H. Ihssen, M. Iodice, A. Izotov, H. E. Jackson, A. Jgoun, C. Jones, R. Kaiser, E. Kinney, M. Kirsch, A. Kisselev, P. Kitching, H. Kobayashi, N. Koch, K. Königsmann, M. Kolstein, H. Kolster, V. Korotkov, W. Korsch, V. Kozlov, L. H. Kramer, B. Krause, V. G. Krivokhijine, M. Kückes, F. Kümmell, G. Kyle, W. Lachnit, W. Lorenzon, A. Lung, N. C. R. Makins, F. K. Martens, J. W. Martin, F. Masoli, A. Mateos, M. McAndrew, K. McIlhany, R. D. McKeown, F. Meissner, F. Menden, D. Mercer, A. Metz, N. Meyners, O. Mikloukho, C. A. Miller, M. A. Miller, R. G. Milner, V. Mitsyn, A. Most, R. Mozzetti, V. Muccifora, A. Nagaitsev, Y. Naryshkin, A. M. Nathan, F. Neunreither, M. Niczyporuk, W.-D. Nowak, M. Nupieri, P. Oelwein, H. Ogami, T. G. O'Neill, R. Openshaw, J. Ouyang, B. R. Owen, V. Papavassiliou, S. F. Pate, M. Pitt, H. R. Poolman, S. Potashov, D. H. Potterveld, B. Povh, G. Rakness, A. Reali, R. Redwine, A. R. Reolon, R. Ristinen, K. Rith, H. Roloff, G. Röper, P. Rossi, S. Rudnitsky, M. Ruh, D. Ryckbosch, Y. Sakemi, I. Savin, C. Scarlett, F. Schmidt, H. Schmitt, G. Schnell, K. P. Schüler, A. Schwind, J. Seibert, T.-A. Shibata, T. Shin, V. Shutov, C. Simani, A. Simon, K. Sinram, P. Slavich, J. Sowinski, M. Spengos, E. Steffens, J. Stenger, J. Stewart, F. Stock, U. Stoesslein, M. Sutter, H. Tallini, S. Taroian, A. Terkulov, D. M. Thiessen, E. Thomas, B. Tipton, A. Trudel, M. Tytgat, G. M. Urciuoli, J. J. van Hunen, R. van de Vyver, J. F. J. van den Brand, G. van der Steenhoven, M. C. Vetterli, V. Vikhrov, M. Vincter, J. Visser, E. Volk, W. Wander, T. P. Welch, S. E. Williamson, T. Wise, T. Wölfel, K. Woller, S. Yoneyama, K. Zapfe-Düren, H. Zohrabian, and R. Zurmühle
Subjects: Physics, HERMES experiment, Particle physics, Meson, 010308 nuclear & particles physics, High Energy Physics::Lattice, High Energy Physics::Phenomenology, Nuclear Theory, General Physics and Astronomy, Virtual particle, 01 natural sciences, Coherence length, Positron energy, Nuclear physics, Deuterium, Nuclear transparency, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, Nucleon
Abstract: Exclusive incoherent electroproduction of the ρ0(770) meson from 1H, 2H, 3He, and 14N targets has been studied by the HERMES experiment at squared four-momentum transfer Q^2>0.4 GeV^2 and positron energy loss ν from 9 to 20 GeV. The ratio of the 14N to 1H cross sections per nucleon, known as the nuclear transparency, was found to decrease with increasing coherence length of quark-antiquark fluctuations of the virtual photon. The data provide clear evidence of the interaction of the quark-antiquark fluctuations with the nuclear medium.
Published: 1999

30. Measurement of the neutron spin structure function g with a polarized 3He internal target

Author: K. Ackerstaff, A. Airapetian, I. Akushevich, N. Akopov, M. Amarian, E.C. Aschenauer, R. Avakian, H. Avakian, A. Avetissian, B. Bains, S. Barrow, M. Beckmann, S. Belostotski, J.E. Belz, Th. Benisch, S. Bernreuther, N. Bianchi, S. Blanchard, J. Blouw, H. Böttcher, A. Borissov, J. Brack, B. Braun, B. Bray, W. Brückner, A. Brüll, E.E.W. Bruins, H.J. Bulten, G.P. Capitani, P. Carter, E. Cisbani, G.R. Court, P.P.J. Delheij, E. Devitsin, C.W. de Jager, E. De Sanctis, D. De Schepper, P.K.A. de Witt Huberts, M. Düren, A. Dvoredsky, G. Elbakian, J. Emerson, A. Fantoni, A. Fechtchenko, M. Ferstl, D. Fick, K. Fiedler, B.W. Filippone, H. Fischer, H.T. Fortune, J. Franz, S. Frullani, M.-A. Funk, N.D. Gagunashvili, P. Galumian, H. Gao, Y. Gärber, F. Garibaldi, P. Geiger, V. Gharibyan, A. Golendoukhin, G. Graw, O. Grebeniouk, P.W. Green, L.G. Greeniaus, C. Grosshauser, A. Gute, V. Gyurjyan, J.P. Haas, W. Haeberli, J.-O. Hansen, D. Hasch, O. Häusser, R.S. Henderson, Th. Henkes, R. Hertenberger, Y. Holler, R.J. Holt, H. Ihssen, M. Iodice, A. Izotov, H.E. Jackson, A. Jgoun, C. Jones, R. Kaiser, E. Kinney, M. Kirsch, A. Kisselev, P. Kitching, N. Koch, K. Königsmann, M. Kolstein, H. Kolster, W. Korsch, V. Kozlov, L.H. Kramer, B. Krause, V.G. Krivokhijine, M. Kückes, G. Kyle, W. Lachnit, W. Lorenzon, A. Lung, N.C.R. Makins, S.I. Manaenkov, F.K. Martens, J.W. Martin, A. Mateos, K. McIlhany, R.D. McKeown, F. Meissner, D. Mercer, A. Metz, N. Meyners, O. Mikloukho, C.A. Miller, M.A. Miller, R.G. Milner, V. Mitsyn, A. Most, R. Mozzetti, V. Muccifora, A. Nagaitsev, Y. Naryshkin, A.M. Nathan, F. Neunreither, M. Niczyporuk, W.-D. Nowak, M. Nupieri, P. Oelwein, H. Ogami, T.G. O'Neill, R. Openshaw, V. Papavassiliou, S.F. Pate, M. Pitt, S. Potashov, D.H. Potterveld, B. Povh, G. Rakness, R. Redwine, A.R. Reolon, R. Ristinen, K. Rith, G. Röper, H. Roloff, P. Rossi, S. Rudnitsky, M. Ruh, D. Ryckbosch, Y. Sakemi, I. Savin, K.P. Schüller, A. Schwind, T.-A. Shibata, T. Shin, A. Simon, K. Sinram, W.R. Smythe, J. Sowinski, M. Spengos, E. Steffens, J. Stenger, J. Stewart, F. Stock, U. Stoesslein, M. Sutter, H. Tallini, S. Taroian, A. Terkulov, D.M. Thiessen, B. Tipton, A. Trudel, M. Tytgat, G.M. Urciuoli, R. Van de Vyver, J.F.J. van den Brand, G. van der Steenhoven, M.C. Vetterli, E. Volk, W. Wander, T.P. Welch, S.E. Williamson, T. Wise, T. Wölfel, K. Zapfe-Düren, H. Zohrabian, and R. Zurmühle
Subjects: Physics, HERMES experiment, Nuclear and High Energy Physics, Range (particle radiation), 010308 nuclear & particles physics, Astrophysics::Cosmology and Extragalactic Astrophysics, HERA, Spin structure, Deep inelastic scattering, 01 natural sciences, Nuclear physics, Positron, 0103 physical sciences, High Energy Physics::Experiment, Neutron, Atomic physics, 010306 general physics, Spin-½
Abstract: Results are reported from the HERMES experiment at HERA on a measurement of the neutron spin structure function g1n(x, Q2) in deep inelastic scattering using 27.5 GeV longitudinally polarized positrons incident on a polarized 3He internal gas target. The data cover the kinematic range 0.023
Published: 1997

31. Precise Measurement of the Neutron Magnetic Form FactorGMnin the Few-GeV2Region

Author: R. J. Feuerbach, J. P. Cummings, L. C. Smith, E. Munevar, R. De Masi, D. Keller, M. Kossov, B. S. Ishkhanov, I. Popa, K. S. Egiyan, G. Ricco, K. Mikhailov, L. Cheng, M. Khandaker, M. Garçon, J. Shaw, Michael Wood, P. Nadel-Turonski, Nikolay Shvedunov, M. R. Niroula, K. Hafidi, R. Nasseripour, S. McAleer, Friedrich Klein, B. P. Quinn, Brian Raue, V. S. Serov, L. Casey, F. X. Girod, Susan Taylor, Marco A. Huertas, M. Lowry, V. Sapunenko, D. P. Watts, L. C. Dennis, B. E. Bonner, Hartmuth Arenhövel, Dinko Pocanic, H. Egiyan, R. G. Fersch, H. Avakian, D. Doughty, B. B. Niczyporuk, G. S. Adams, S. Park, D. Sharov, N. Kalantarians, P. L. Cole, Sylvain Bouchigny, Sabine Jeschonnek, R. C. Minehart, Kei Moriya, D. Heddle, P. Rossi, J. Lachniet, H. G. Juengst, C. A. Meyer, N. Pivnyuk, K. Joo, W. J. Briscoe, B. L. Berman, A. Tkabladze, G. V. Fedotov, E. Pasyuk, D. Rowntree, A. Coleman, L. M. Qin, M. Y. Gabrielyan, S. E. Kuhn, S. A. Dytman, V. Crede, Y. Ilieva, J. R. Calarco, T. Mineeva, J. W. Price, M. J. Amaryan, C. Paterson, S. Strauch, M. MacCormick, A.V. Stavinsky, M. Klusman, I. Hleiqawi, V. P. Kubarovsky, K. P. Adhikari, S. L. Careccia, A. Empl, L. El Fassi, O. Pogorelko, B. Moreno, D. P. Weygand, J. Salamanca, R. Suleiman, M. E. McCracken, Elton Smith, K. L. Giovanetti, B. Asavapibhop, G. V. O'Rielly, Tsutomu Mibe, Larry Weinstein, Z. W. Zhao, J. W C McNabb, D. J. Tedeschi, D. Protopopescu, D. G. Jenkins, Barry Ritchie, M. Anghinolfi, James Mueller, S. Malace, S. A. Morrow, P. Rubin, I. Bedlinskiy, G. S. Mutchler, Konstantin Stopani, S. Pozdniakov, V. Gyurjyan, M. M. Ito, C. Djalali, Y. G. Sharabian, G. Rosner, T. Kageya, K. Livingston, D. S. Dale, X. Wei, R. Dickson, V. Kuznetsov, C. E. Hyde-Wright, H. Denizli, N. Guler, N. A. Baltzell, P. Mattione, K. A. Griffioen, M. S. Saini, A. V. Skabelin, P. Dragovitsch, J. Zhang, S. Barrow, E. De Sanctis, S. Niccolai, J. T. Goetz, E. Polli, H. Bagdasaryan, R. A. Miskimen, J. D. Kellie, B. McKinnon, Sergey Kuleshov, M. Bektasoglu, J. Hardie, M. Nozar, W. Kim, Laird Kramer, G. Niculescu, D. I. Sober, D. Branford, M. Guidal, R. A. Schumacher, H. Hakobyan, M. Mirazita, P. Khetarpal, C. Hanretty, J. M. Laget, M. Holtrop, Victor Mokeev, L. Graham, J. R. Johnstone, N. Gevorgyan, L. Guo, M. Ungaro, M. Osipenko, F. Sabatié, A. Daniel, K. Beard, Kalvir S. Dhuga, S. Bültmann, A. I. Ostrovidov, J. Yun, D. Cords, V. Batourine, T. A. Forest, A. Yegneswaran, A. C S Lima, A. Sandorfi, K. Park, R. Fatemi, S. Stepanyan, A. V. Vlassov, D. G. Ireland, Volker D. Burkert, A. S. Biselli, J. Pierce, Avraham Klein, B. Zhao, J. Langheinrich, R. De Vita, A. Fradi, S. S. Stepanyan, S. A. Philips, William Brooks, N. Markov, P. Konczykowski, B. E. Stokes, J. J. Manak, S. Anefalos Pereira, G. E. Dodge, H. Y. Lu, N. Dashyan, Maryam Moteabbed, P. V. Degtyarenko, K. V. Dharmawardane, I. Niculescu, D. Lawrence, D. Schott, F. W. Hersman, M. Battaglieri, N. Baillie, P. Stoler, K. Hicks, G. Asryan, O. P. Dzyubak, R. A. Niyazov, P. Corvisiero, R. Bradford, B. A. Mecking, K. Lukashin, E. Wolin, Gerard Gilfoyle, M. Guillo, D. Sokhan, W. Gohn, N. Hassall, M. Bellis, E. Golovatch, J. P. Ball, J. Hu, Y. Prok, D. S. Carman, S. Dhamija, M. D. Mestayer, L. Elouadrhiri, I. I. Strakovsky, E. L. Isupov, R. W. Gothe, G. Gavalian, S. Tkachenko, A. Deur, Michael L. Williams, J. Kuhn, N. Benmouna, J. P. Santoro, Andrei Afanasev, M. Ripani, D. G. Crabb, K. Y. Kim, Roy Thompson, Cynthia Marie Hadjidakis, S. Boiarinov, Michael Dugger, B. M. Preedom, Douglas Higinbotham, M. Yurov, Lorenzo Zana, H. S. Jo, C. Bookwalter, C. Salgado, Kwangsoo Kim, G. Riccardi, P. Eugenio, A. Starostin, M. Taiuti, Michael Vineyard, and P. Collins
Subjects: Physics, 010308 nuclear & particles physics, Scattering, Nuclear Theory, General Physics and Astronomy, Scintillator, 7. Clean energy, 01 natural sciences, Nuclear physics, Dipole, Deuterium, 0103 physical sciences, Magnetic form factor, Neutron detection, High Energy Physics::Experiment, Neutron, Nuclear Experiment, 010306 general physics, Electron scattering
Abstract: The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q;{2}=1.0-4.8 GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.
Published: 2009

32. Search for the Photoexcitation of Exotic Mesons in theπ+π+π−System

Author: M. Nozar, C. Salgado, D. P. Weygand, L. Guo, G. Adams, Ji Li, P. Eugenio, M. J. Amaryan, M. Anghinolfi, G. Asryan, H. Avakian, H. Bagdasaryan, N. Baillie, J. P. Ball, N. A. Baltzell, S. Barrow, M. Battaglieri, I. Bedlinskiy, M. Bektasoglu, M. Bellis, N. Benmouna, B. L. Berman, A. S. Biselli, L. Blaszczyk, B. E. Bonner, S. Bouchigny, S. Boiarinov, R. Bradford, D. Branford, W. J. Briscoe, W. K. Brooks, S. Bültmann, V. D. Burkert, C. Butuceanu, J. R. Calarco, S. L. Careccia, D. S. Carman, B. Carnahan, L. Casey, A. Cazes, S. Chen, L. Cheng, P. L. Cole, P. Collins, P. Coltharp, D. Cords, P. Corvisiero, D. Crabb, H. Crannell, V. Crede, J. P. Cummings, D. Dale, N. Dashyan, R. De Masi, R. De Vita, E. De Sanctis, P. V. Degtyarenko, H. Denizli, L. Dennis, A. Deur, K. V. Dharmawardane, K. S. Dhuga, R. Dickson, C. Djalali, G. E. Dodge, D. Doughty, M. Dugger, S. Dytman, O. P. Dzyubak, H. Egiyan, K. S. Egiyan, L. El Fassi, L. Elouadrhiri, R. Fatemi, G. Fedotov, R. J. Feuerbach, T. A. Forest, A. Fradi, H. Funsten, M. Garçon, G. Gavalian, N. Gevorgyan, G. P. Gilfoyle, K. L. Giovanetti, F. X. Girod, J. T. Goetz, R. W. Gothe, K. A. Griffioen, M. Guidal, M. Guillo, N. Guler, V. Gyurjyan, C. Hadjidakis, K. Hafidi, H. Hakobyan, C. Hanretty, J. Hardie, N. Hassall, D. Heddle, F. W. Hersman, K. Hicks, I. Hleiqawi, M. Holtrop, C. E. Hyde-Wright, Y. Ilieva, D. G. Ireland, B. S. Ishkhanov, E. L. Isupov, M. M. Ito, D. Jenkins, H. S. Jo, J. R. Johnstone, K. Joo, H. G. Juengst, N. Kalantarians, J. D. Kellie, M. Khandaker, W. Kim, A. Klein, F. J. Klein, M. Kossov, Z. Krahn, L. H. Kramer, V. Kubarovsky, J. Kuhn, S. E. Kuhn, S. V. Kuleshov, V. Kuznetsov, J. Lachniet, J. M. Laget, J. Langheinrich, D. Lawrence, K. Livingston, H. Y. Lu, M. MacCormick, N. Markov, P. Mattione, S. McAleer, B. McKinnon, J. W. C. McNabb, B. A. Mecking, S. Mehrabyan, M. D. Mestayer, C. A. Meyer, T. Mibe, K. Mikhailov, M. Mirazita, R. Miskimen, V. Mokeev, B. Moreno, K. Moriya, S. A. Morrow, M. Moteabbed, J. Mueller, E. Munevar, G. S. Mutchler, P. Nadel-Turonski, R. Nasseripour, S. Niccolai, G. Niculescu, I. Niculescu, B. B. Niczyporuk, M. R. Niroula, R. A. Niyazov, G. V. O’Rielly, M. Osipenko, A. I. Ostrovidov, K. Park, E. Pasyuk, C. Paterson, S. Anefalos Pereira, S. A. Philips, J. Pierce, N. Pivnyuk, D. Pocanic, O. Pogorelko, E. Polli, I. Popa, S. Pozdniakov, B. M. Preedom, J. W. Price, Y. Prok, D. Protopopescu, L. M. Qin, B. A. Raue, G. Riccardi, G. Ricco, M. Ripani, B. G. Ritchie, F. Ronchetti, G. Rosner, P. Rossi, P. D. Rubin, F. Sabatié, J. Salamanca, J. P. Santoro, V. Sapunenko, R. A. Schumacher, V. S. Serov, Y. G. Sharabian, D. Sharov, N. V. Shvedunov, A. V. Skabelin, E. S. Smith, L. C. Smith, D. I. Sober, D. Sokhan, A. Stavinsky, S. S. Stepanyan, S. Stepanyan, B. E. Stokes, P. Stoler, I. I. Strakovsky, S. Strauch, M. Taiuti, D. J. Tedeschi, U. Thoma, A. Tkabladze, S. Tkachenko, L. Todor, M. Ungaro, M. F. Vineyard, A. V. Vlassov, D. P. Watts, L. B. Weinstein, M. Williams, E. Wolin, M. H. Wood, A. Yegneswaran, L. Zana, J. Zhang, B. Zhao, and Z. W. Zhao
Subjects: Quantum chromodynamics, Physics, Particle physics, Meson, 010308 nuclear & particles physics, Partial wave analysis, Bremsstrahlung, General Physics and Astronomy, 01 natural sciences, 7. Clean energy, Nuclear physics, Excited state, 0103 physical sciences, Isobar, Production (computer science), 010306 general physics, Spin-½
Abstract: A search for exotic mesons in the $$\pi^{+}\pi^{+}\pi^{-}$$ system photoproduced by the charge exchange reaction $$\gamma p\to \pi^{+}\pi^{+}\pi^{-}(n)$$ was carried out by the CLAS collaboration at Jefferson Lab. A tagged-photon beam with energies in the 4.8 to 5.4 GeV range, produced through bremsstrahlung from a 5.744 GeV electron beam, was incident on a liquid-hydrogen target. A Partial Wave Analysis (PWA) was performed on a sample of 83,000 events, the highest such statistics to date in this reaction at these energies. The main objective of this study was to look for the photoproduction of an exotic $$J^{PC} = 1^{-+}$$ resonant state in the 1 to 2 GeV mass range. Our PWA analysis, based on the isobar model, shows production of the $$a_{2}(1320)$$ and the $$\pi_{2}(1670)$$ mesons, but no evidence for the $$a_{1}(1260)$$, nor the $$\pi_{1}(1600)$$ exotic state at the expected levels. An upper limit of 13.5 nb is determined for the exotic $$\pi_1(1600)$$ cross section, less than 2% of the $a_2(1320)
Published: 2009

33. Measurement of semi-inclusive pi+ electroproduction off the proton

Author: L. C. Smith, E. Munevar, M. H. Wood, Y. Ilieva, M. E. McCracken, P. Nadel-Turonski, E. Wolin, R. J. Feuerbach, B. S. Ishkhanov, G. E. Dodge, Tsutomu Mibe, P. V. Degtyarenko, J. P. Ball, Y. Prok, D. S. Carman, M. R. Niroula, Alexander Ilyichev, O. P. Dzyubak, I. I. Strakovsky, Paolo Rossi, K. S. Egiyan, P. L. Cole, Z. W. Zhao, J. Lachniet, A. Tkabladze, W. Kim, I. Niculescu, R. A. Niyazov, D. G. Crabb, R. S. Hakobyan, L. El Fassi, Elton Smith, A. Deur, G. Niculescu, R. De Masi, B. L. Berman, J. Kuhn, B. McKinnon, W. K. Brooks, G. P. Gilfoyle, K. Livingston, R. Fatemi, N. Markov, A. V. Vlassov, J. P. Cummings, M. Anghinolfi, G. Ricco, B. Zhao, D. J. Tedeschi, S. Niccolai, R. Dickson, Ji Li, Y. G. Sharabian, S. Strauch, D. P. Watts, H. Egiyan, L. M. Qin, C. Paterson, L. Zana, D. Branford, J. M. Laget, M. Khandaker, G. Riccardi, N. Hassall, M. Bellis, Cynthia Marie Hadjidakis, R. De Vita, A. I. Ostrovidov, K. A. Griffioen, N. Guler, F. W. Hersman, J. Hardie, C. Butuceanu, M. J. Amaryan, M. Kossov, Shifeng Chen, E. N. Golovach, Volker D. Burkert, A. S. Biselli, Michael Dugger, J. Langheinrich, H. O. Funsten, H. G. Juengst, Luca Trentadue, M. MacCormick, I. Hleiqawi, M. D. Mestayer, C. Djalali, H. Denizli, P. Eugenio, S. Dytman, A. V. Skabelin, S. L. Careccia, I. Popa, P. Coltharp, R. A. Schumacher, P. Mattione, M. Osipenko, S. Barrow, M. Taiuti, A.V. Stavinsky, S. Anefalos Pereira, P. D. Rubin, R. W. Gothe, Laird Kramer, E. L. Isupov, D. Lawrence, D. Sokhan, M. M. Ito, H. Hakobyan, A. Cazes, J. R. Calarco, C. I O Gordon, K. L. Giovanetti, S. Mehrabyan, Alexei V. Klimenko, J. T. Goetz, R. Miskimen, C. Hanretty, G. V. O'Rielly, E. Polli, Michael L. Williams, Larry Weinstein, M. Mirazita, Kalvir S. Dhuga, J. D. Kellie, P. Collins, Friedrich Klein, F. Sabatié, Nikolay Shvedunov, J. J. Melone, V. Sapunenko, Sylvain Bouchigny, S. Bültmann, L. Todor, Barry Ritchie, Dinko Pocanic, Victor Mokeev, Brian Raue, G. Asryan, E. De Sanctis, M. Battaglieri, I. Bedlinskiy, V. A. Drozdov, S. Stepanyan, S. E. Kuhn, N. A. Baltzell, D. Protopopescu, S. Pozdniakov, M. Garçon, M. F. Vineyard, J. Pierce, Avraham Klein, Z. Krahn, N. Dashyan, S. Boiarinov, U. Thoma, D. I. Sober, R. Bradford, N. Kalantarians, Latifa Elouadrhiri, V. Gyurjyan, G. S. Mutchler, D. G. Ireland, V. Crede, N. Baillie, B. B. Niczyporuk, R. C. Minehart, Kei Moriya, S. McAleer, N. Pivnyuk, B. E. Stokes, J. Napolitano, G. S. Adams, J. Zhang, B. M. Preedom, F. X. Girod, L. Blaszczyk, H. Bagdasaryan, J. P. Santoro, C. Tur, C. A. Meyer, L. Guo, M. Ungaro, G. Gavalian, J. Donnelly, S. Tkachenko, D. Heddle, J. Salamanca, N. Benmouna, G. V. Fedotov, M. Ripani, J. W C McNabb, D. Jenkins, R. Nasseripour, S. A. Morrow, K. Joo, Maryam Moteabbed, Bernhard Mecking, K. V. Dharmawardane, A. Yegneswaran, Atilla Gonenc, P. Ambrozewicz, J. W. Price, M. Holtrop, D. P. Weygand, P. Corvisiero, H. S. Jo, Gerald Feldman, Federico A. Ceccopieri, C. Salgado, G. Rosner, M. Guillo, K. Mikhailov, M. Guidal, H. Y. Lu, C. E. Hyde-Wright, P. Stoler, Sergey Kuleshov, M. Bektasoglu, M. Nozar, K. Hicks, S. S. Stepanyan, S. A. Philips, J. Mueller, K. Hafidi, V. S. Serov, K. Park, V. P. Kubarovsky, O. Pogorelko, L. C. Dennis, B. E. Bonner, H. Avakian, W. J. Briscoe, E. Pasyuk, D. Doughty, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, CLAS, and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Particle physics, Nuclear and High Energy Physics, Proton, DEEP-INELASTIC-SCATTERING, TARGET FRAGMENTATION REGION, TRANSVERSE-MOMENTUM, PARTON DISTRIBUTIONS, AZIMUTHAL ASYMMETRY, PION ELECTROPRODUCTION, CHARGED HADRONS, HARD PROCESSES, LEADING ORDER, CROSS-SECTION, TARGET FRAGMENTATION REGION, Hadron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Spectral line, Nuclear physics, Pion, Factorization, 0103 physical sciences, 010306 general physics, Nuclear Experiment, PION ELECTROPRODUCTION, Physics, DEEP-INELASTIC-SCATTERING, 010308 nuclear & particles physics, LEADING ORDER, TRANSVERSE-MOMENTUM, Azimuth, Diquark, CHARGED HADRONS, HARD PROCESSES, PARTON DISTRIBUTIONS, Cathode ray, AZIMUTHAL ASYMMETRY, High Energy Physics::Experiment, CROSS-SECTION
Abstract: Semi-inclusive {pi}{sup +} electroproduction on protons has been measured with the CLAS detector at Jefferson Lab. The measurement was performed on a liquid-hydrogen target using a 5.75 GeV electron beam. The complete five-fold differential cross sections were measured over a wide kinematic range including the complete range of azimuthal angles between hadronic and leptonic planes, {phi}, enabling us to separate the {phi}-dependent terms. Our measurements of the {phi}-independent term of the cross section at low Bjorken x were found to be in fairly good agreement with pQCD calculations. Indeed, the conventional current fragmentation calculation can account for almost all of the observed cross section, even at small {pi}{sup +} momentum. The measured center-of-momentum spectra are in qualitative agreement with high-energy data, which suggests a surprising numerical similarity between the spectator diquark fragmentation in the present reaction and the antiquark fragmentation measured in e{sup +}e{sup -} collisions. We have observed that the two {phi}-dependent terms of the cross section are small. Within our precision the cos2{phi} term is compatible with zero, except for the low-z region, and the measured cos{phi} term is much smaller in magnitude than the sum of the Cahn and Berger effects.
Published: 2009

34. Electroexcitation of the Roper resonance for1.7<Q2<4.5GeV2ine→p→enπ+

Author: B. Zhao, F. W. Hersman, Marco Ripani, S. Dhamija, R. W. Gothe, K. Y. Kim, J. Kuhn, J. P. Santoro, E. De Sanctis, Latifa Elouadrhiri, B. M. Preedom, P. Eugenio, R. C. Minehart, Kei Moriya, D. I. Sober, M. Taiuti, G. Rosner, C. A. Meyer, M. Battaglieri, G. V. Fedotov, P. Collins, J. J. Melone, Lorenzo Zana, R. Bradford, K. Lukashin, J. Shaw, V. Batourine, D. P. Weygand, H. Hakobyan, Friedrich Klein, H. S. Jo, Michael Wood, K. Hafidi, Brian Raue, Gerald Feldman, Elton Smith, R. Fatemi, V. S. Serov, A. V. Vlassov, T. Lee, M. Anghinolfi, P. Coltharp, James Mueller, I. I. Strakovsky, N. A. Baltzell, R. De Vita, P. D. Rubin, A. Cazes, Maryam Moteabbed, C. Salgado, Bernhard Mecking, Y. G. Sharabian, A. Deur, K. A. Griffioen, K. S. Egiyan, K. V. Dharmawardane, Baile Zhang, Alexei V. Klimenko, S. Anefalos Pereira, Z. Krahn, W. K. Brooks, Shifeng Chen, J. D. Kellie, Y. Prok, N. Hassall, M. Bellis, J. Langheinrich, Barry Ritchie, N. Baillie, P. Mattione, M. S. Saini, L. C. Dennis, B. E. Bonner, S. S. Stepanyan, S. A. Philips, R. A. Miskimen, B. McKinnon, H. Avakian, J. T. Goetz, E. Polli, B. L. Berman, D. Sharov, M. Mirazita, D. Branford, K. Livingston, D. S. Dale, Ji Li, L. M. Qin, J. M. Laget, H. Denizli, N. Gevorgyan, C. Paterson, G. Gavalian, W. J. Briscoe, E. Pasyuk, S. Tkachenko, M. D. Mestayer, S. A. Dytman, J. Donnelly, G. Asryan, A. V. Skabelin, N. Benmouna, Gerard Gilfoyle, O. P. Dzyubak, R. A. Niyazov, E. L. Isupov, A. Fradi, D. Sokhan, M. Guillo, V. Crede, Michael L. Williams, W. Gohn, N. Markov, V. Sapunenko, Dinko Pocanic, J. R. Calarco, P. Corvisiero, E. Golovatch, S. Boiarinov, S. E. Kuhn, Charles Hyde, V. P. Kubarovsky, O. Pogorelko, C. Tur, M. J. Amaryan, M. MacCormick, I. Hleiqawi, R. Nasseripour, S. L. Careccia, S. McAleer, F. X. Girod, Laird Kramer, B. E. Stokes, G. S. Adams, J. P. Cummings, Cynthia Marie Hadjidakis, G. E. Dodge, H. Y. Lu, K. L. Giovanetti, L. Blaszczyk, P. V. Degtyarenko, M. Kossov, V. Gyurjyan, K. Joo, I. Popa, Sergey Kuleshov, M. Bektasoglu, Michael Dugger, D. Heddle, M. Nozar, P. Stoler, I. Niculescu, D. Lawrence, J. Zhang, R. De Masi, D. Schott, S. A. Morrow, C. Djalali, R. A. Schumacher, M. Guidal, Larry Weinstein, K. Hicks, M. Holtrop, L. Graham, H. Bagdasaryan, C. I O Gordon, P. Ambrozewicz, S. Bültmann, L. Morand, T. A. Forest, S. Stepanyan, J. Pierce, Avraham Klein, K. Mikhailov, L. Cheng, Nikolay Shvedunov, A. I. Ostrovidov, L. Casey, A. C S Lima, K. Park, N. Kalantarians, B. B. Niczyporuk, D. G. Ireland, Michael Vineyard, N. Pivnyuk, Giovanni Ricco, Atilla Gonenc, E. Wolin, Volker D. Burkert, A. S. Biselli, J. P. Ball, D. S. Carman, D. G. Crabb, J. Salamanca, J. W C McNabb, M. Yurov, J. W. Price, S. Mehrabyan, C. Bookwalter, G. Riccardi, H. Funsten, P. Nadel-Turonski, C. Butuceanu, Tsutomu Mibe, N. Dashyan, K. Hafnaoui, C. Hanretty, G. V. O'Rielly, J. R. Johnstone, Z. W. Zhao, D. Keller, Paolo Rossi, D. G. Jenkins, J. Lachniet, A. Tkabladze, S. Park, Sylvain Bouchigny, D. Rowntree, M. M. Ito, R. S. Hakobyan, L. El Fassi, M. Khandaker, H. G. Juengst, A.V. Stavinsky, D. J. Tedeschi, V. Mokeev, I. Bedlinskiy, L. C. Smith, E. Munevar, B. S. Ishkhanov, M. R. Niroula, V. Kuznetsov, S. Strauch, R. Suleiman, L. Guo, G. S. Mutchler, M. Ungaro, S. Niccolai, J. Hardie, D. Doughty, W. Kim, D. P. Watts, G. Niculescu, J. Yun, D. Cords, H. Egiyan, T. Takeuchi, A. Yegneswaran, M. Osipenko, F. Sabatié, Kalvir S. Dhuga, M. Y. Gabrielyan, R. Dickson, R. J. Feuerbach, N. Guler, Inna Aznauryan, P. L. Cole, S. Barrow, L. Todor, D. Protopopescu, S. Pozdniakov, M. Garçon, Y. Ilieva, and B. Moreno
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Roper resonance, Meson production, 010308 nuclear & particles physics, State (functional analysis), 01 natural sciences, Helicity, Baryon, 0103 physical sciences, Pi, Isobar, 010306 general physics, Ground state
Abstract: The helicity amplitudes of the electroexcitation of the Roper resonance are extracted for $1.7l{Q}^{2}l4.5\phantom{\rule{0.3em}{0ex}}{\mathrm{GeV}}^{2}$ from recent high precision JLab-CLAS cross section and longitudinally polarized beam asymmetry data for ${\ensuremath{\pi}}^{+}$ electroproduction on protons at $W=1.15\ensuremath{-}1.69$ GeV. The analysis is made using two approaches, dispersion relations and a unitary isobar model, which give consistent ${Q}^{2}$ behavior of the helicity amplitudes for the ${\ensuremath{\gamma}}^{*}p\ensuremath{\rightarrow}$N(1440)P${}_{11}$ transition. It is found that the transverse helicity amplitude ${A}_{1/2}$, which is large and negative at ${Q}^{2}=0$, becomes large and positive at ${Q}^{2}\ensuremath{\simeq}2\phantom{\rule{0.3em}{0ex}}{\mathrm{GeV}}^{2}$, and then drops slowly with ${Q}^{2}$. The longitudinal helicity amplitude ${S}_{1/2}$, which was previously found from CLAS $\stackrel{\ensuremath{\rightarrow}}{e}p\ensuremath{\rightarrow}\mathit{ep}{\ensuremath{\pi}}^{0},\mathit{en}{\ensuremath{\pi}}^{+}$ data to be large and positive at ${Q}^{2}=0.4,0.65\phantom{\rule{0.3em}{0ex}}{\mathrm{GeV}}^{2}$, drops with ${Q}^{2}$. Available model predictions for ${\ensuremath{\gamma}}^{*}p\ensuremath{\rightarrow}$N(1440)P${}_{11}$ allow us to conclude that these results provide strong evidence in favor of N(1440)P${}_{11}$ as a first radial excitation of the $3q$ ground state. The results of the present paper also confirm the conclusion of our previous analysis for ${Q}^{2}l1$ GeV${}^{2}$ that the presentation of N(1440)P${}_{11}$ as a q$^{3}\mathrm{G}$ hybrid state is ruled out.
Published: 2008

35. Electroproduction ofϕ(1020)mesons at1.4⩽Q2⩽3.8GeV2measured with the CLAS spectrometer

Author: M. Guidal, R. Nasseripour, M. Holtrop, I. I. Strakovsky, R. J. Feuerbach, G. V. O'Rielly, Cynthia Marie Hadjidakis, B. Zhao, Z. W. Zhao, D. G. Jenkins, Alexei V. Klimenko, R. De Masi, A. Deur, Michael Dugger, H. O. Funsten, Michael Wood, K. Hafidi, N. Dashyan, B. E. Stokes, G. S. Adams, Barry Ritchie, P. L. Cole, B. M. Preedom, V. S. Serov, C. E. Hyde-Wright, S. McAleer, J. Langheinrich, S. S. Stepanyan, S. A. Philips, L. Blaszczyk, G. Ricco, J. Ball, F. W. Hersman, Sergey Kuleshov, Lorenzo Zana, J. P. Santoro, M. Bektasoglu, M. Nozar, M. Garçon, Elton Smith, M. Battaglieri, J. Salamanca, J. Lachniet, A. Tkabladze, Latifa Elouadrhiri, P. Coltharp, H. Hakobyan, F. Sabatié, H. S. Jo, K. Livingston, D. S. Dale, J. W C McNabb, J. R. Ficenec, N. A. Baltzell, V. Kuznetsov, R. Bradford, R. C. Minehart, Kei Moriya, C. A. Meyer, J. W. Price, M. M. Ito, S. Strauch, V. Mokeev, C. Salgado, L. Cheng, B. L. Berman, L. M. Qin, D. P. Watts, H. Egiyan, K. A. Griffioen, J. P. Cummings, V. Gyurjyan, G. V. Fedotov, S. A. Morrow, M. Anghinolfi, E. De Sanctis, V. P. Kubarovsky, D. Keller, Nikolay Shvedunov, Friedrich Klein, R. Dickson, James Mueller, C. Paterson, D. I. Sober, O. Pogorelko, C. Djalali, E. Munevar, D. P. Weygand, L. C. Smith, M. Kossov, L. C. Dennis, J. Zhang, B. E. Bonner, H. Avakian, Ji Li, M. Guillo, Brian Raue, S. Niccolai, I. Popa, S. Dhamija, N. Hassall, M. Bellis, H. Bagdasaryan, F. X. Girod, B. S. Ishkhanov, S. Park, R. Fatemi, N. Kalantarians, W. Gohn, A. V. Vlassov, J. R. Johnstone, D. Sharov, M. D. Mestayer, Y. G. Sharabian, Sylvain Bouchigny, J. Hardie, H. G. Juengst, J. Kuhn, L. El Fassi, C. Marchand, G. Audit, E. Wolin, H. Denizli, E. L. Isupov, R. De Vita, J. D. Kellie, L. Morand, Michael L. Williams, P. Rossi, N. Guler, William Brooks, Christian Weiss, A.V. Stavinsky, M. R. Niroula, R. W. Gothe, S. Boiarinov, W. Kim, M. Mirazita, W. J. Briscoe, L. Casey, G. Gavalian, C. Hanretty, S. Tkachenko, S. Anefalos Pereira, G. Niculescu, P. Nadel-Turonski, N. Benmouna, J. P. Ball, Tsutomu Mibe, Y. Prok, D. S. Carman, A. V. Skabelin, A. Cazes, Maryam Moteabbed, Hall Crannell, Bernhard Mecking, D. J. Tedeschi, M. Ripani, E. Pasyuk, V. Crede, Shifeng Chen, G. Rosner, K. V. Dharmawardane, J. R. Calarco, S. A. Dytman, I. Bedlinskiy, B. B. Niczyporuk, L. Guo, M. Ungaro, N. Pivnyuk, D. G. Crabb, R. A. Schumacher, M. Khandaker, S. Barrow, P. Mattione, M. S. Saini, P. Eugenio, M. Taiuti, K. Joo, G. S. Mutchler, Michael Vineyard, D. Cords, L. Graham, C. I O Gordon, A. Yegneswaran, M. Yurov, J. T. Goetz, S. Mehrabyan, S. Bültmann, V. Sapunenko, P. Collins, Dinko Pocanic, J. J. Melone, M. Osipenko, S. Procureur, T. A. Forest, C. Bookwalter, G. Riccardi, S. Stepanyan, S. E. Kuhn, Kalvir S. Dhuga, C. Butuceanu, J. Pierce, Avraham Klein, C. Tur, G. E. Dodge, L. Todor, H. Y. Lu, P. V. Degtyarenko, M. J. Amaryan, D. Protopopescu, M. MacCormick, I. Hleiqawi, S. Pozdniakov, I. Niculescu, D. Lawrence, S. L. Careccia, D. Schott, K. L. Giovanetti, Larry Weinstein, D. Doughty, D. Heddle, Y. Ilieva, B. Moreno, R. A. Miskimen, B. McKinnon, D. Branford, J. M. Laget, N. Gevorgyan, A. I. Ostrovidov, K. Park, D. G. Ireland, Volker D. Burkert, A. S. Biselli, Z. Krahn, N. Baillie, Laird Kramer, Gerard Gilfoyle, D. Sokhan, A. Fradi, N. Markov, G. Asryan, O. P. Dzyubak, R. A. Niyazov, P. Corvisiero, K. S. Egiyan, K. Mikhailov, P. Stoler, and K. Hicks
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, Vector meson dominance, 01 natural sciences, Helicity, Gluon, 0103 physical sciences, Exponent, Vector meson, 010306 general physics, Nucleon, Exchange model
Abstract: Electroproduction of exclusive \ensuremath{\phi} vector mesons has been studied with the CLAS detector in the kinematic range $1.4\ensuremath{\leqslant}{Q}^{2}\ensuremath{\leqslant}3.8$ GeV${}^{2},0.0\ensuremath{\leqslant}{t}^{'}\ensuremath{\leqslant}3.6$ GeV${}^{2}$, and $2.0\ensuremath{\leqslant}W\ensuremath{\leqslant}3.0$ GeV. The scaling exponent for the total cross section as $1/({Q}^{2}+{M}_{\ensuremath{\phi}}^{2}){}^{n}$ was determined to be $n=2.49\ifmmode\pm\else\textpm\fi{}0.33$. The slope of the four-momentum transfer ${t}^{'}$ distribution is ${b}_{\ensuremath{\phi}}=0.98\ifmmode\pm\else\textpm\fi{}0.17$ GeV${}^{\ensuremath{-}2}$. Under the assumption of $s$-channel helicity conservation, we determine the ratio of longitudinal to transverse cross sections to be $R=0.86\ifmmode\pm\else\textpm\fi{}0.24$. A two-gluon exchange model is able to reproduce the main features of the data.
Published: 2008

36. Ratios ofN15/C12andHe4/C12inclusive electroproduction cross sections in the nucleon resonance region

Author: K. S. Egiyan, L. Guo, K. Mikhailov, Calarco, P. Stoler, K. Hicks, Susan Taylor, M. Ungaro, C. D. Keith, J. Donnelly, G. Asryan, O. P. Dzyubak, R. A. Niyazov, H. Egiyan, P. Corvisiero, C. E. Hyde-Wright, Y. Ilieva, R. A. Miskimen, G. Ricco, M. Amarian, E. Wolin, B. Zhao, B. McKinnon, R. Fatemi, S. Strauch, Laird Kramer, K. Park, B. B. Niczyporuk, P. Dragovitsch, Nikolay Shvedunov, J. P. Ball, Y. Prok, D. S. Carman, K. Joo, L. M. Qin, R. Suleiman, D. Branford, N. Pivnyuk, Shifeng Chen, A. V. Vlassov, Sergey Kuleshov, J. Yun, D. Cords, M. Mirazita, D. G. Crabb, J. M. Laget, M. Bektasoglu, G. S. Mutchler, S. Niccolai, A. Yegneswaran, M. Battaglieri, Niroula, A. Fradi, M. Nozar, N. A. Baltzell, J. Hardie, P. Eugenio, H. G. Juengst, S. A. Morrow, R. De Vita, O. Pogorelko, C. Djalali, Kubarovsky, C. Paterson, Friedrich Klein, K. A. Griffioen, R. J. Feuerbach, N. Markov, K. Livingston, M. Klusman, M. Taiuti, A.V. Stavinsky, N. Kalantarians, Brian Raue, F. W. Hersman, R. Bradford, K. Lukashin, Marco A. Huertas, D. J. Tedeschi, J. Langheinrich, A. I. Ostrovidov, A. C S Lima, J. T. Goetz, J. Shaw, E. Polli, S. S. Stepanyan, Crede, S. A. Philips, P. Collins, D. G. Ireland, Michael Wood, K. Hafidi, I. Bedlinskiy, Batourine, Elton Smith, Gerard Gilfoyle, Mestayer, Volker D. Burkert, V. S. Serov, L. C. Dennis, A. S. Biselli, N. Guler, B. E. Bonner, H. Avakian, B. Carnahan, G. Gavalian, S. Tkachenko, M. Anghinolfi, N. Benmouna, M. Ripani, Kwangsoo Kim, J. Kuhn, J. Zhang, S Anefalos, R. W. Gothe, G. Riccardi, A. Cazes, James Mueller, J. W C McNabb, Maryam Moteabbed, Bernhard Mecking, J. D. Kellie, S. Barrow, C. Butuceanu, K. V. Dharmawardane, E. Pasyuk, H. Bagdasaryan, Mokeev, Cynthia Marie Hadjidakis, E. De Sanctis, P. D. Rubin, K. Y. Kim, Y. G. Sharabian, M. Guidal, S. A. Dytman, R. G. Fersch, Michael Dugger, H. O. Funsten, L. Todor, N. Baillie, D. I. Sober, D. Protopopescu, M. Holtrop, S. Pozdniakov, M. Garçon, Hong Lu, Sbr Ultmann, Dinko Pocanic, Sylvain Bouchigny, P. L. Cole, P. Rossi, S. E. Kuhn, M. Bellis, J. Lachniet, H. Denizli, A. Tkabladze, D. Rowntree, Sapunenko, R. S. Hakobyan, A. V. Skabelin, P. Nadel-Turonski, Tsutomu Mibe, R. C. Minehart, C. A. Meyer, G. V. Fedotov, B. E. Stokes, G. S. Adams, D. P. Weygand, U. Thoma, M. Khandaker, L. C. Smith, B. S. Ishkhanov, D. Doughty, D. Heddle, Gyurjyan, W. Kim, S. Stepanyan, G. Niculescu, M. MacCormick, I. Hleiqawi, G. Rosner, R. Nasseripour, P. Bosted, S. L. Careccia, K. L. Giovanetti, Larry Weinstein, P. Coltharp, M. M. Ito, M. Osipenko, F. Sabatié, M. Guillo, K. Beard, L. Elouadrhiri, A. Deur, W. K. Brooks, R. A. Schumacher, G. V. O'Rielly, E. Golovatch, L. Morand, T. A. Forest, J. Pierce, Avraham Klein, Z. W. Zhao, J. P. Cummings, Hall Crannell, M. Kossov, D. G. Jenkins, G. E. Dodge, P. V. Degtyarenko, S. McAleer, F. X. Girod, I. Niculescu, D. Lawrence, J. W. Price, R. De Masi, Ji Li, E. L. Isupov, Michael L. Williams, S. Boiarinov, Michael Vineyard, B. M. Preedom, Lorenzo Zana, J. P. Santoro, H. S. Jo, and C. Salgado
Subjects: Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Scattering, Hadron, Carbon-12, Deep inelastic scattering, 01 natural sciences, Nuclear physics, Baryon, Helium-4, 0103 physical sciences, Phenomenological model, Atomic physics, 010306 general physics, Nucleon
Abstract: The (W,Q{sup 2}) dependence of the ratio of inclusive electron scattering cross sections for {sup 15}N/{sup 12}C was determined in the kinematic ranges 0.8
Published: 2008

37. Polarized structure functionσLT'forH1(e→,e'K+)Λin the nucleon resonance region

Author: L. C. Dennis, B. E. Bonner, S. McAleer, F. X. Girod, L. Blaszczyk, H. Avakian, D. Sharov, D. Lawrence, P. Stoler, K. Hicks, K. S. Egiyan, Laird Kramer, D. Doughty, L. C. Smith, E. Munevar, V. Mokeev, K. Mikhailov, Elton Smith, J. Langheinrich, S. S. Stepanyan, S. A. Philips, W. J. Briscoe, E. Pasyuk, B. S. Ishkhanov, D. P. Watts, S. A. Dytman, R. A. Schumacher, P. Eugenio, D. Heddle, H. Egiyan, J. W. Price, M. F. Vineyard, G. Asryan, O. P. Dzyubak, R. A. Niyazov, P. Nadel-Turonski, Tsutomu Mibe, H. G. Juengst, P. Corvisiero, E. Wolin, M. Taiuti, M. Anghinolfi, M. Kossov, James Mueller, E. De Sanctis, M. R. Niroula, J. P. Ball, M. Battaglieri, Y. Ilieva, P. D. Rubin, Y. G. Sharabian, A.V. Stavinsky, D. S. Carman, Patrick Girard, W. Kim, T. A. Forest, G. Niculescu, J. Lachniet, D. I. Sober, R. J. Feuerbach, Michael Wood, A. I. Ostrovidov, V. Sapunenko, L. Casey, Dinko Pocanic, R. Bradford, K. Lukashin, D. J. Tedeschi, K. Park, C. Hanretty, S. Stepanyan, K. Hafidi, D. G. Crabb, J. Pierce, V. S. Serov, S. E. Kuhn, Avraham Klein, E. Anciant, B. E. Stokes, B. B. Niczyporuk, I. Bedlinskiy, G. Ricco, D. G. Ireland, B. Moreno, G. E. Dodge, H. Y. Lu, P. V. Degtyarenko, N. Pivnyuk, Volker D. Burkert, A. S. Biselli, G. Audit, C. E. Hyde-Wright, R. Fatemi, A. V. Vlassov, R. De Vita, Z. W. Zhao, V. Kuznetsov, K. Joo, S. Procureur, Maryam Moteabbed, B. Zhao, D. G. Jenkins, Bernhard Mecking, Z. Krahn, Shifeng Chen, D. Sayre, S. Strauch, P. Collins, D. Protopopescu, I. Niculescu, M. Khandaker, S. Pozdniakov, Sylvain Bouchigny, J. J. Manak, P. Rossi, N. Baillie, S. Anefalos Pereira, A. Fradi, C. Cetina, A. Shafi, P. Dragovitsch, P. Mattione, Friedrich Klein, Kwangsoo Kim, R. A. Miskimen, B. McKinnon, V. P. Kubarovsky, G. Riccardi, J. Salamanca, Sergey Kuleshov, M. Osipenko, R. De Masi, Brian Raue, D. Branford, M. Mirazita, J. M. Laget, J. W C McNabb, S. A. Morrow, C. Djalali, G. S. Mutchler, M. Bektasoglu, S. Niccolai, F. Sabatié, N. Gevorgyan, C. Butuceanu, K. Beard, F. W. Hersman, N. A. Baltzell, J. T. Goetz, K. Livingston, D. S. Dale, N. Markov, O. Pogorelko, P. Coltharp, V. Crede, K. A. Griffioen, R. Dickson, J. Hardie, M. J. Amaryan, Kalvir S. Dhuga, P. Ambrozewicz, Gerard Gilfoyle, M. Nozar, D. Sokhan, M. MacCormick, M. Bellis, I. Hleiqawi, M. M. Ito, S. L. Careccia, J. Kuhn, R. W. Gothe, G. Gavalian, N. Guler, J. R. Calarco, G. A. Peterson, S. Simionatto, J. D. Kellie, S. Taylor, S. Tkachenko, K. Y. Kim, K. L. Giovanetti, B. Asavapibhop, J. P. Santoro, Roy Thompson, Larry Weinstein, S. Barrow, N. Benmouna, M. Ripani, M. Guidal, M. Guillo, L. Cheng, M. D. Mestayer, G. Rosner, R. Nasseripour, Nikolay Shvedunov, J. Hu, E. L. Isupov, L. Elouadrhiri, M. Holtrop, Michael L. Williams, S. Boiarinov, I. I. Strakovsky, B. M. Preedom, A. Deur, Lorenzo Zana, N. Kalantarians, H. Hakobyan, H. S. Jo, Gerald Feldman, Michael Dugger, W. K. Brooks, K. Wang, H. O. Funsten, C. Salgado, B. L. Berman, L. M. Qin, C. Paterson, Thierry Auger, M. Garçcon, J. R. Johnstone, V. Gyurjyan, J. Zhang, H. Bagdasaryan, L. Guo, M. Ungaro, A. Tkabladze, J. Yun, D. Cords, L. El Fassi, A. Yegneswaran, P. L. Cole, Y. Prok, Barry Ritchie, R. C. Minehart, Kei Moriya, C. A. Meyer, G. V. Fedotov, D. P. Weygand, A. V. Skabelin, and N. Dashyan
Subjects: Physics, Nuclear and High Energy Physics, Angular range, 010308 nuclear & particles physics, Hydrogen-1, Structure function, Hyperon, Sigma, Resonance, Lambda, 01 natural sciences, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon
Abstract: The first measurements of the polarized structure function {sigma}{sub LT{sup '}} for the reaction {sup 1}H(e-vector,e{sup '}K{sup +}){lambda} in the nucleon resonance region are reported. Measurements are included from threshold up to W=2.05 GeV for central values of Q{sup 2} of 0.65 and 1.00 GeV{sup 2}, and nearly the entire kaon center-of-mass angular range. {sigma}{sub LT{sup '}} is the imaginary part of the longitudinal-transverse response and is expected to be sensitive to interferences between competing intermediate s-channel resonances, as well as resonant and nonresonant processes. The results for {sigma}{sub LT{sup '}} are comparable in magnitude to previously reported results from CLAS for {sigma}{sub LT}, the real part of the same response. An intriguing sign change in {sigma}{sub LT{sup '}} is observed in the high Q{sup 2} data at W{approx_equal}1.9 GeV. Comparisons to several existing model predictions are shown.
Published: 2008

38. Light Vector Mesons in the Nuclear Medium

Author: V. Crede, S. McAleer, L. Blaszczyk, J. R. Calarco, B. L. Berman, E. De Sanctis, S. Tkachenko, M. Taiuti, R. A. Schumacher, Michael Wood, A. I. Ostrovidov, G. Asryan, C. I O Gordon, K. Hafidi, K. Park, C. Paterson, J. W. Price, O. P. Dzyubak, R. A. Niyazov, V. S. Serov, L. C. Dennis, D. G. Ireland, B. G. Ritchie, B. E. Stokes, J. Kuhn, M. R. Niroula, Cynthia Marie Hadjidakis, M. J. Amaryan, H. Avakian, M. MacCormick, I. Hleiqawi, Volker D. Burkert, G. S. Adams, S. L. Careccia, A. S. Biselli, S. Stepanyan, D. Sharov, A. V. Vlassov, Philip L. Cole, Larry Weinstein, J. Pierce, Avraham Klein, Chaden Djalali, K.H. Hicks, D. J. Tedeschi, K. Joo, Sylvain Bouchigny, G. S. Mutchler, Michael Dugger, W. Kim, Gerard Gilfoyle, D. Sokhan, H. S. Jo, K. S. Egiyan, J. Hardie, Friedrich Klein, J. P. Cummings, Laird Kramer, K. Livingston, S. A. Dytman, W. K. Brooks, B. Carnahan, S. Niccolai, H. O. Funsten, P. Collins, Ulrich Mosel, Z. W. Zhao, I. Bedlinskiy, H. G. Juengst, G. Niculescu, R. Nasseripour, K. Mikhailov, R. A. Miskimen, B. McKinnon, H. Hakobyan, S. Anefalos Pereira, D. G. Jenkins, P. Coltharp, Hall Crannell, A.V. Stavinsky, P. Eugenio, R. W. Gothe, V. Sapunenko, M. Bektasoglu, C. Salgado, Dinko Pocanic, M. M. Ito, D. Branford, V. Gyurjyan, P. Khetarpal, A. Fradi, M. Holtrop, M. Kossov, J. M. Laget, D. P. Weygand, Y. Ilieva, V. P. Kubarovsky, R. De Vita, L. C. Smith, E. Munevar, G. E. Dodge, B. S. Ishkhanov, P. Nadel-Turonski, H. Bagdasaryan, P. V. Degtyarenko, N. Guler, S. E. Kuhn, Federico Ronchetti, J. J. Melone, K. Moriya, C. Hanretty, I. Niculescu, D. Lawrence, J. D. Kellie, Victor Mokeev, J. R. Johnstone, L. Guo, M. Ungaro, Latifa Elouadrhiri, G. Rosner, J. Lachniet, A. Tkabladze, M. Guidal, A. Yegneswaran, R. C. Minehart, S. Barrow, C. Tur, P. Rossi, J. Langheinrich, S. S. Stepanyan, E. Pasyuk, J. Zhang, C. A. Meyer, S. Mehrabyan, F. X. Girod, Baile Zhang, G. V. Fedotov, G. Gavalian, R. S. Hakobyan, R. Dickson, M. Ripani, L. El Fassi, D. Doughty, Z. Krahn, N. Benmouna, G. Riccardi, B. A. Raue, M. Osipenko, C. Butuceanu, Tsutomu Mibe, L. Cheng, Shifeng Chen, N. Baillie, Daniel S. Carman, F. Sabatié, Nikolay Shvedunov, K. L. Giovanetti, S. V. Kuleshov, D. Protopopescu, G. Ricco, S. Pozdniakov, M. Garçon, E. Wolin, C. E. Hyde-Wright, O. Pogorelko, J. Ball, N. Kalantarians, M. Khandaker, D. G. Crabb, M. Nozar, B. Zhao, H. Denizli, H. Y. Lu, J. T. Goetz, F. W. Hersman, M. Mirazita, Elton Smith, N. Dashyan, James Mueller, Alexei V. Klimenko, Y. Prok, I. I. Strakovsky, Y. G. Sharabian, P. Muehlich, A. Deur, Ji Li, M. D. Mestayer, R. J. Feuerbach, E. L. Isupov, Michael L. Williams, Maryam Moteabbed, Bernhard Mecking, K. V. Dharmawardane, S. Boiarinov, B. M. Preedom, Lorenzo Zana, J. P. Santoro, M. Battaglieri, D. P. Watts, H. Egiyan, Gerald Feldman, N. A. Baltzell, N. Markov, R. Bradford, K. A. Griffioen, N. Hassall, M. Bellis, J. Salamanca, P. Mattione, J. W C McNabb, M. Anghinolfi, L. Casey, B. B. Niczyporuk, Michael Vineyard, N. Pivnyuk, W. J. Briscoe, L. Todor, S. A. Morrow, S. Strauch, P. Ambrozewicz, P. Stoler, D. I. Sober, Thomas Jefferson National Accelerator Facility (Jefferson Lab), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, CLAS, and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Nuclear and High Energy Physics, Particle physics, Rho meson, Meson, Nuclear Theory, FOS: Physical sciences, light vector mesons, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, chiral symmetry, Spectral line, Nuclear physics, ENHANCEMENT, CLAS, 0103 physical sciences, 11.30.Rd, 14.40.Cs, 24.85.+p, QCD SUM-RULES, Invariant mass, RHO-MESON, Nuclear Experiment (nucl-ex), 010306 general physics, in-medium modifications, Nuclear Experiment, Physics, AU COLLISIONS, QCD sum rules, CEBAF, 010308 nuclear & particles physics, QCD SUM-RULES, RHO-MESON, SPECTRAL-FUNCTION, AU COLLISIONS, OMEGA-MESONS, MATTER, CLAS, ENHANCEMENT, SYSTEM, CEBAF, Nuclear matter, SPECTRAL-FUNCTION, Deuterium, Mass spectrum, High Energy Physics::Experiment, MATTER, SYSTEM, OMEGA-MESONS
Abstract: The light vector mesons ($\rho$, $\omega$, and $\phi$) were produced in deuterium, carbon, titanium, and iron targets in a search for possible in-medium modifications to the properties of the $\rho$ meson at normal nuclear densities and zero temperature. The vector mesons were detected with the CEBAF Large Acceptance Spectrometer (CLAS) via their decays to $e^{+}e^{-}$. The rare leptonic decay was chosen to reduce final-state interactions. A combinatorial background was subtracted from the invariant mass spectra using a well-established event-mixing technique. The $\rho$ meson mass spectrum was extracted after the $\omega$ and $\phi$ signals were removed in a nearly model-independent way. Comparisons were made between the $\rho$ mass spectra from the heavy targets ($A > 2$) with the mass spectrum extracted from the deuterium target. With respect to the $\rho$-meson mass, we obtain a small shift compatible with zero. Also, we measure widths consistent with standard nuclear many-body effects such as collisional broadening and Fermi motion., Comment: 15 pages, 18 figures, 3 tables
Published: 2008

39. Cross sections and beam asymmetries fore→p→enπ+in the nucleon resonance region for1.7⩽Q2⩽4.5GeV2

Author: R. Fatemi, A. V. Vlassov, T. Lee, H. G. Juengst, A. Fradi, R. De Vita, A.V. Stavinsky, N. Markov, N. Hassall, B. Zhao, D. J. Tedeschi, S. Park, Sylvain Bouchigny, K. Hafnaoui, K. Livingston, D. S. Dale, G. Rosner, R. Nasseripour, I. Bedlinskiy, S. Anefalos Pereira, P. Rossi, E. Wolin, R. Dickson, Ji Li, J. P. Ball, Y. Prok, F. W. Hersman, V. Kuznetsov, J. P. Cummings, V. Sapunenko, Dinko Pocanic, C. Hanretty, N. Guler, S. McAleer, F. X. Girod, L. Blaszczyk, D. G. Ireland, V. Crede, S. E. Kuhn, M. Osipenko, F. Sabatié, J. Lachniet, H. Denizli, A. Tkabladze, J. R. Johnstone, M. Kossov, J. R. Calarco, D. G. Crabb, D. Rowntree, J. Donnelly, G. Asryan, O. P. Dzyubak, R. A. Niyazov, A. I. Ostrovidov, A. C S Lima, R. Suleiman, I. Popa, G. S. Mutchler, L. Guo, G. E. Dodge, H. Y. Lu, M. Ungaro, D. Doughty, M. D. Mestayer, S. Niccolai, E. De Sanctis, Volker D. Burkert, A. S. Biselli, E. L. Isupov, C. Tur, M. Guillo, D. Heddle, W. Gohn, M. Guidal, J. Hardie, Z. Krahn, J. Kuhn, P. L. Cole, S. Barrow, Elton Smith, Friedrich Klein, M. Yurov, Kalvir S. Dhuga, Michael L. Williams, P. V. Degtyarenko, N. Baillie, M. Anghinolfi, James Mueller, A. V. Skabelin, L. Todor, D. Protopopescu, S. Mehrabyan, D. I. Sober, S. Pozdniakov, M. Garçon, J. Yun, D. Cords, S. S. Stepanyan, S. Boiarinov, P. D. Rubin, Y. G. Sharabian, A. Yegneswaran, R. A. Miskimen, Brian Raue, B. McKinnon, Atilla Gonenc, R. C. Minehart, Kei Moriya, C. A. Meyer, J. W. Price, T. Takeuchi, M. Holtrop, I. Niculescu, C. Bookwalter, G. V. Fedotov, W. Kim, G. Niculescu, G. Gavalian, Laird Kramer, G. Riccardi, D. Lawrence, Baile Zhang, Shifeng Chen, S. Dhamija, J. Shaw, P. Corvisiero, S. Tkachenko, L. El Fassi, D. Branford, Michael Wood, R. De Masi, B. E. Stokes, K. Hafidi, C. Butuceanu, D. Keller, D. Schott, G. S. Adams, N. A. Baltzell, V. Gyurjyan, N. Benmouna, M. Ripani, K. Joo, N. Dashyan, P. Mattione, D. P. Weygand, M. S. Saini, M. Mirazita, J. M. Laget, V. S. Serov, R. W. Gothe, Y. Ilieva, N. Gevorgyan, Michael Vineyard, J. Zhang, P. Nadel-Turonski, Alexei V. Klimenko, L. Cheng, Tsutomu Mibe, B. M. Preedom, L. Elouadrhiri, J. Langheinrich, K. Y. Kim, Nikolay Shvedunov, J. T. Goetz, E. Polli, H. Bagdasaryan, Lorenzo Zana, J. P. Santoro, Barry Ritchie, S. A. Philips, M. Khandaker, P. Eugenio, M. Taiuti, G. V. O'Rielly, Z. W. Zhao, I. I. Strakovsky, P. Stoler, J. D. Kellie, S. A. Morrow, V. P. Kubarovsky, V. Mokeev, R. A. Schumacher, B. Moreno, Gerard Gilfoyle, G. Ricco, C. Djalali, H. Hakobyan, H. S. Jo, Gerald Feldman, K. Hicks, O. Pogorelko, A. Deur, D. G. Jenkins, Federico Ronchetti, L. C. Dennis, L. Graham, P. Collins, B. E. Bonner, J. J. Melone, C. Salgado, D. Sokhan, K. Park, Daniel S. Carman, M. J. Amaryan, K. S. Egiyan, C. I O Gordon, N. Kalantarians, H. Avakian, W. K. Brooks, M. MacCormick, I. Hleiqawi, C. E. Hyde-Wright, D. Sharov, P. Ambrozewicz, K. Mikhailov, S. Bültmann, L. Morand, T. A. Forest, Cynthia Marie Hadjidakis, S. L. Careccia, Sergey Kuleshov, S. Stepanyan, K. L. Giovanetti, J. Pierce, Avraham Klein, Larry Weinstein, M. Bektasoglu, M. Nozar, Michael Dugger, H. O. Funsten, W. J. Briscoe, E. Pasyuk, S. A. Dytman, J. Salamanca, J. W C McNabb, L. Casey, B. B. Niczyporuk, N. Pivnyuk, V. Batourine, M. Battaglieri, L. C. Smith, E. Munevar, B. S. Ishkhanov, B. L. Berman, R. Bradford, B. A. Mecking, K. Lukashin, L. M. Qin, R. S. Hakobyan, K. A. Griffioen, C. Paterson, M. Klusman, D. P. Watts, M. R. Niroula, E. Golovatch, M. Bellis, S. Strauch, H. Egiyan, A. Cazes, Maryam Moteabbed, P. Coltharp, K. V. Dharmawardane, M. Y. Gabrielyan, R. J. Feuerbach, M. M. Ito, and Inna Aznauryan
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, Resonance, 01 natural sciences, Excited state, Isospin, 0103 physical sciences, Production (computer science), Invariant mass, Sensitivity (control systems), Atomic physics, 010306 general physics, Nucleon
Abstract: The exclusive electroproduction process $\stackrel{\ensuremath{\rightarrow}}{e}p\ensuremath{\rightarrow}{e}^{'}n{\ensuremath{\pi}}^{+}$ was measured in the range of the photon virtuality ${Q}^{2}=1.7\text{\ensuremath{-}}4.5 {\mathrm{GeV}}^{2}$, and the invariant mass range for the $n{\ensuremath{\pi}}^{+}$ system of $W=1.15\text{\ensuremath{-}}1.7 \mathrm{GeV}$ using the CEBAF Large Acceptance Spectrometer. For the first time, these kinematics are probed in exclusive ${\ensuremath{\pi}}^{+}$ production from protons with nearly full coverage in the azimuthal and polar angles of the $n{\ensuremath{\pi}}^{+}$ center-of-mass system. The $n{\ensuremath{\pi}}^{+}$ channel has particular sensitivity to the isospin \textonehalf{} excited nucleon states, and together with the $p{\ensuremath{\pi}}^{0}$ final state will serve to determine the transition form factors of a large number of resonances. The largest discrepancy between these results and present modes was seen in the ${\ensuremath{\sigma}}_{{\mathit{LT}}^{'}}$ structure function. In this experiment, 31,295 cross section and 4,184 asymmetry data points were measured. Because of the large volume of data, only a reduced set of structure functions and Legendre polynomial moments can be presented that are obtained in model-independent fits to the differential cross sections.
Published: 2008

40. π0photoproduction on the proton for photon energies from 0.675 to 2.875 GeV

Author: B. M. Preedom, J. P. Ball, D. S. Carman, L. C. Dennis, B. E. Bonner, R. A. Schumacher, H. Avakian, J. Kuhn, J. P. Santoro, Roy Thompson, B. Carnahan, D. G. Crabb, P. Eugenio, M. Taiuti, P. Collins, R. A. Niyazov, F. Sabatié, S. Bültmann, T. A. Forest, A. I. Ostrovidov, J. Langheinrich, A. C S Lima, W. J. Briscoe, V. Gyurjyan, S. S. Stepanyan, P. Stoler, J. Slamanca, S. A. Philips, S. Stepanyan, H. S. Jo, Gerald Feldman, E. Pasyuk, Valeria Muccifora, J. Pierce, Avraham Klein, D. Doughty, S. A. Dytman, D. G. Ireland, K. Wang, K. Hicks, J. Zhang, H. Bagdasaryan, D. Heddle, L. Elouadrhiri, R. J. Feuerbach, I. I. Strakovsky, Volker D. Burkert, B. B. Niczyporuk, A. S. Biselli, Gerard Gilfoyle, Marco A. Huertas, H. G. Juengst, L. Zana, G. E. Dodge, P. Coltharp, A. Deur, B. E. Stokes, W. K. Brooks, N. Pivnyuk, P. V. Degtyarenko, G. S. Adams, W. Kim, G. Gavalian, A.V. Stavinsky, J. Shaw, G. Niculescu, J. Napolitano, B. L. Berman, J. Donnelly, G. Asryan, O. P. Dzyubak, S. Tkachenko, Federico Ronchetti, Kwangsoo Kim, G. Riccardi, R. Fatemi, C. Butuceanu, Laird Kramer, M. M. Ito, L. M. Qin, F. W. Hersman, M. Kossov, A. V. Vlassov, Sylvain Bouchigny, P. Rossi, E. Anciant, G. V. O'Rielly, M. D. Mestayer, K. Joo, I. Niculescu, D. Lawrence, N. Benmouna, P. Corvisiero, M. Ripani, Carlos A. Salgado, G. Ricco, Michael L. Williams, Victor Mokeev, T. Lee, D. J. Tedeschi, M. Amarian, L. Guo, P. Nadel-Turonski, Tsutomu Mibe, Z. Krahn, Y. Ilieva, M. Spraker, M. Ungaro, Michael Wood, V. S. Serov, M. Guidal, Susan Taylor, S. Strauch, M. Khandaker, N. Baillie, C. Paterson, M. Klusman, S. Boiarinov, J. P. Cummings, R. De Vita, R. A. Miskimen, K. Park, K. S. Egiyan, B. McKinnon, D. G. Jenkins, H. Egiyan, L. C. Maximon, K. Mikhailov, A. Coleman, I. Hleiqawi, H. R. Weller, J. R. Calarco, M. Guillo, I. Bedlinskiy, S. L. Careccia, S. Simionatto, M. Holtrop, S. McAleer, Friedrich Klein, D. Branford, F. X. Girod, Brian Raue, N. Kalantarians, Hall Crannell, J. J. Manak, M. Osipenko, M. Mirazita, K. L. Giovanetti, B. Asavapibhop, Cynthia Marie Hadjidakis, J. M. Laget, A. Tkabladze, J. Yun, D. Cords, Larry Weinstein, J. W C McNabb, D. Rowntree, K. Beard, L. C. Smith, A. Yegneswaran, Michael Dugger, H. O. Funsten, Michael Vineyard, V. P. Kubarovsky, Nicola Bianchi, R. W. Gothe, B. S. Ishkhanov, Kalvir S. Dhuga, C. Marchand, V. Kuznetsov, S. A. Morrow, C. Djalali, L. Todor, A. Empl, R. S. Hakobyan, O. Pogorelko, K. Y. Kim, G. Rosner, R. Nasseripour, E. De Sanctis, D. Protopopescu, J. W. Price, M. R. Niroula, S. Pozdniakov, M. Garçon, G. Audit, C. E. Hyde-Wright, J. Lachniet, D. I. Sober, A. Shafi, P. Ambrozewicz, P. Dragovitsch, M. Bektasoglu, M. Nozar, K. Livingston, S. Niccolai, P. L. Cole, R. Dickson, J. Hardie, N. Guler, S. Barrow, M. Battaglieri, N. A. Baltzell, K. A. Griffioen, J. D. Kellie, Ron L. Workman, R. Bradford, K. Lukashin, G. S. Mutchler, M. Bellis, J. Hu, Alexei V. Klimenko, R. A. Arndt, Barry Ritchie, Bernhard Mecking, K. V. Dharmawardane, R. C. Minehart, Kei Moriya, C. A. Meyer, G. V. Fedotov, Y. Prok, D. P. Weygand, H. Denizli, A. V. Skabelin, Shifeng Chen, J. T. Goetz, V. Sapunenko, Dinko Pocanic, S. E. Kuhn, C. Tur, Elton Smith, J. R. Ficenec, M. Anghinolfi, James Mueller, P. D. Rubin, Y. G. Sharabian, and E. Wolin
Subjects: Physics, Normalization (statistics), Nuclear and High Energy Physics, Particle physics, Photon, Spectrometer, Proton, 010308 nuclear & particles physics, Forward scatter, Scattering, 01 natural sciences, Particle identification, Nuclear physics, 0103 physical sciences, Photon beam, Nuclear Experiment, 010306 general physics
Abstract: Differential cross sections for the reaction $\gamma p \to p \pi^0$ have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged photon beam with energies from 0.675 to 2.875 GeV. The results reported here possess greater accuracy in the absolute normalization than previous measurements. They disagree with recent CB-ELSA measurements for the process at forward scattering angles. Agreement with the SAID and MAID fits is found below 1 GeV. The present set of cross sections has been incorporated into the SAID database, and exploratory fits have been extended to 3 GeV. Resonance couplings have been extracted and compared to previous determinations.
Published: 2007

41. Experimental Study of ExclusiveH2(e,e′p)nReaction Mechanisms at HighQ2

Author: Y. Ilieva, V. Gyurjyan, R. Miskimen, N. Dashyan, J. Zhang, M. Guillo, G. Gavalian, H. Bagdasaryan, S. A. Morrow, S. Tkachenko, S. Mehrabyan, M. Guidal, G. Riccardi, N. Benmouna, E. Wolin, V. Sapunenko, Alexei V. Klimenko, J. P. Ball, D. S. Carman, Dinko Pocanic, R. J. Feuerbach, L. Guo, M. Ungaro, M. Holtrop, P. Eugenio, R. G. Fersch, D. G. Crabb, D. Lawrence, C. Marchand, J. P. Cummings, S. E. Kuhn, A. Deur, L. Todor, D. Protopopescu, S. Pozdniakov, M. Garçon, P. L. Cole, Marco Ripani, Y. Prok, Barry Ritchie, M. Kossov, M. Taiuti, V. Mokeev, S. Bouchigny, R. A. Schumacher, Nikolay Shvedunov, C. Tur, W. K. Brooks, E. De Sanctis, M. Khandaker, Elton Smith, G. Audit, C. E. Hyde-Wright, K. Livingston, C. I O Gordon, R. Dickson, S. Bültmann, D. Cords, P. Nadel-Turonski, Tsutomu Mibe, M. Battaglieri, D. I. Sober, Federico Ronchetti, Sergey Kuleshov, C. Djalali, A. Yegneswaran, M. J. Amaryan, M. Anghinolfi, M. Nozar, N. Kalantarians, N. Guler, S. Stepanyan, Ji Li, P. Coltharp, M. M. Ito, James Mueller, P. Collins, Cynthia Marie Hadjidakis, I. Hleiqawi, J. Pierce, Avraham Klein, R. Fatemi, B. L. Berman, J. Langheinrich, S. S. Stepanyan, Michael Dugger, R. Bradford, G. S. Mutchler, J. J. Melone, J. Lachniet, S. L. Careccia, A. Tkabladze, Z. Krahn, S. Barrow, Michael Wood, A. V. Vlassov, Y. G. Sharabian, G. E. Dodge, H. Y. Lu, H. Denizli, L. C. Smith, E. Munevar, G. V. O'Rielly, P. Ambrozewicz, K. Hafidi, M. D. Mestayer, S. Niccolai, M. Osipenko, B. S. Ishkhanov, P. Rossi, N. A. Baltzell, Friedrich Klein, N. Baillie, P. V. Degtyarenko, V. S. Serov, L. C. Dennis, C. Hanretty, K. L. Giovanetti, Brian Raue, K. A. Griffioen, E. L. Isupov, Z. W. Zhao, M. Bellis, Larry Weinstein, R. S. Hakobyan, S. Strauch, J. Hardie, H. G. Juengst, D. P. Watts, D. Doughty, H. Avakian, R. De Vita, D. G. Ireland, L. El Fassi, Michael L. Williams, V. Crede, M. MacCormick, Shifeng Chen, W. Kim, D. G. Jenkins, I. Niculescu, H. Egiyan, C. Paterson, G. Niculescu, A. V. Skabelin, A.V. Stavinsky, M. R. Niroula, J. R. Calarco, R. De Masi, A. Cazes, Maryam Moteabbed, Bernhard Mecking, B. Zhao, K. V. Dharmawardane, P. Mattione, S. Anefalos Pereira, W. J. Briscoe, E. Pasyuk, S. Boiarinov, B. M. Preedom, Latifa Elouadrhiri, Gerard Gilfoyle, S. McAleer, J. D. Kellie, R. C. Minehart, Kei Moriya, D. J. Tedeschi, F. X. Girod, L. Blaszczyk, C. A. Meyer, S. A. Dytman, D. Sokhan, G. V. Fedotov, J. Kuhn, J. T. Goetz, K. Park, J. Salamanca, I. Bedlinskiy, Laird Kramer, H. S. Jo, F. W. Hersman, B. McKinnon, Lorenzo Zana, J. W C McNabb, J. P. Santoro, V. Batourine, V. P. Kubarovsky, D. P. Weygand, D. Branford, O. Pogorelko, Giovanni Ricco, M. Mirazita, J. M. Laget, Atilla Gonenc, F. Sabatié, N. Gevorgyan, B. B. Niczyporuk, R. W. Gothe, J. W. Price, N. Pivnyuk, H. Hakobyan, Gerald Feldman, G. Rosner, R. Nasseripour, C. Salgado, B. E. Stokes, G. S. Adams, M. Bektasoglu, K. Joo, P. Stoler, C. Butuceanu, Michael Vineyard, K. Hicks, N. Markov, J. Donnelly, G. Asryan, O. P. Dzyubak, R. A. Niyazov, U. Thoma, P. Corvisiero, A. I. Ostrovidov, K. S. Egiyan, Volker D. Burkert, A. S. Biselli, and K. Mikhailov
Subjects: Physics, Nuclear reaction, Reaction mechanism, Particle physics, 010308 nuclear & particles physics, Partial wave analysis, Hadron, General Physics and Astronomy, Elementary particle, 01 natural sciences, Delta baryon, Chemical kinetics, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon
Abstract: The reaction 2H(e,e'p)n has been studied with full kinematic coverage for photon virtuality 1.75 NN transition is the primary contribution at higher momenta.
Published: 2007

42. Separated structure functions for the exclusive electroproduction ofK+ΛandK+Σ0final states

Author: Y. Ilieva, L. C. Dennis, B. E. Bonner, J. Kuhn, J. P. Santoro, Elton Smith, D. P. Watts, Roy Thompson, Nicola Bianchi, R. W. Gothe, H. Avakian, H. Egiyan, Latifa Elouadrhiri, R. C. Minehart, Kei Moriya, D. G. Ireland, P. Eugenio, V. Crede, M. Taiuti, P. Collins, Michael Dugger, C. A. Meyer, H. O. Funsten, K. Livingston, P. L. Cole, M. Anghinolfi, G. V. Fedotov, R. A. Miskimen, B. McKinnon, K. Y. Kim, N. Markov, A. Tkabladze, J. R. Calarco, E. Wolin, R. Dickson, I. I. Strakovsky, James Mueller, D. Rowntree, D. Branford, E. De Sanctis, A. Deur, K. S. Egiyan, W. J. Briscoe, P. D. Rubin, J. P. Ball, B. Zhao, E. Pasyuk, M. Mirazita, J. M. Laget, N. Guler, J. Lachniet, D. I. Sober, A. I. Ostrovidov, D. Doughty, W. K. Brooks, Y. G. Sharabian, D. P. Weygand, K. Mikhailov, L. El Fassi, D. G. Crabb, V. Batourine, S. A. Dytman, Volker D. Burkert, R. Fatemi, G. V. O'Rielly, D. Heddle, Daniel S. Carman, A. S. Biselli, S. Barrow, A. V. Vlassov, G. Gavalian, F. W. Hersman, P. Dragovitsch, Z. W. Zhao, L. Farhi, S. Tkachenko, V. Sapunenko, D. Sayre, N. Benmouna, M. Ripani, P. Nadel-Turonski, Dinko Pocanic, D. G. Jenkins, D. Protopopescu, Kwangsoo Kim, G. Riccardi, M. Amarian, D. Lawrence, Nikolay Shvedunov, J. P. Cummings, C. E. Hyde-Wright, A. V. Skabelin, K. Park, S. Pozdniakov, M. Garçon, C. Butuceanu, Tsutomu Mibe, P. Stoler, R. De Vita, Laird Kramer, N. Baillie, A. Shafi, S. McAleer, M. Osipenko, F. Sabatié, N. Kalantarians, S. E. Kuhn, F. X. Girod, K. Beard, M. Kossov, P. Coltharp, S. Niccolai, K. Hicks, Valeria Muccifora, B. L. Berman, Sylvain Bouchigny, C. Tur, Y. Prok, Barry Ritchie, Kalvir S. Dhuga, L. M. Qin, Gerard Gilfoyle, R. J. Feuerbach, M. M. Ito, Sergey Kuleshov, M. Guillo, M. Bektasoglu, P. Rossi, M. Nozar, V. P. Kubarovsky, J. Donnelly, G. Asryan, V. Frolov, D. Sokhan, O. P. Dzyubak, R. A. Niyazov, C. Paterson, Atilla Gonenc, J. W. Price, M. Klusman, W. Kim, J. Hardie, M. MacCormick, I. Hleiqawi, L. C. Smith, Shifeng Chen, B. S. Ishkhanov, S. L. Careccia, P. Corvisiero, S. Simionatto, G. Niculescu, K. L. Giovanetti, B. Asavapibhop, S. Taylor, Larry Weinstein, M. R. Niroula, M. Khandaker, H. G. Juengst, M. Guidal, M. Bellis, J. Salamanca, V. Mokeev, M. Holtrop, A.V. Stavinsky, C. Cetina, J. T. Goetz, Jian Zhang, E. Polli, Michael Vineyard, J. Langheinrich, S. S. Stepanyan, S. A. Philips, D. J. Tedeschi, I. Bedlinskiy, J. W C McNabb, J. Hu, M. D. Mestayer, E. L. Isupov, B. B. Niczyporuk, S. Boiarinov, Maryam Moteabbed, N. Pivnyuk, B. M. Preedom, Bernhard Mecking, Lorenzo Zana, J. Napolitano, H. Hakobyan, H. S. Jo, Gerald Feldman, K. Wang, C. Salgado, S. A. Morrow, C. Djalali, M. Battaglieri, R. Bradford, P. Ambrozewicz, K. Lukashin, N. A. Baltzell, K. A. Griffioen, J. J. Manak, J. D. Kellie, S. Strauch, G. S. Mutchler, Mathew Williams, V. Gyurjyan, H. Bagdasaryan, L. Guo, M. Ungaro, K. Joo, J. Yun, D. Cords, A. Yegneswaran, B. E. Stokes, G. Ricco, G. Rosner, R. Nasseripour, A. Empl, O. Pogorelko, Patrick Girard, Michael Wood, K. Hafidi, V. S. Serov, Friedrich Klein, Brian Raue, Federico Ronchetti, G. E. Dodge, H. Y. Lu, P. V. Degtyarenko, I. Niculescu, R. De Masi, R. A. Schumacher, S. Bültmann, T. A. Forest, S. Stepanyan, J. Pierce, Avraham Klein, and N. Dashyan
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Proton, 010308 nuclear & particles physics, Momentum transfer, Hyperon, Sigma, Strangeness, Lambda, 01 natural sciences, Nuclear physics, 0103 physical sciences, High Energy Physics::Experiment, Production (computer science), Nuclear Experiment, 010306 general physics, Energy (signal processing)
Abstract: We report measurements of the exclusive electroproduction of K{sup +}{lambda} and K{sup +}{sigma}{sup 0} final states from a proton target using the Continuous Electron Beam Accelerator Facility (CEBAF) large-acceptance spectrometer (CLAS) detector at the Thomas Jefferson National Accelerator Facility. The separated structure functions {sigma}{sub T},{sigma}{sub L},{sigma}{sub TT}, and {sigma}{sub LT} were extracted from the {phi}- and {epsilon}-dependent differential cross sections taken with electron beam energies of 2.567, 4.056, and 4.247 GeV. This analysis represents the first {sigma}{sub L}/{sigma}{sub T} separation with the CLAS detector, and the first measurement of the kaon electroproduction structure functions away from parallel kinematics. The data span a broad range of momentum transfers from 0.5{
Published: 2007

43. First measurement of beam-recoil observablesCxandCzin hyperon photoproduction

Author: V. Gyurjyan, L. C. Dennis, B. E. Bonner, H. Avakian, Maryam Moteabbed, Bernhard Mecking, J. Zhang, K. V. Dharmawardane, H. Bagdasaryan, K. Park, F. Sabatiã, V. P. Kubarovsky, A. Empl, O. Pogorelko, S. A. Morrow, K. Lukashin, W. J. Briscoe, E. Pasyuk, L. C. Smith, V. Sapunenko, Dinko Pocanic, S. A. Dytman, B. S. Ishkhanov, Barry Ritchie, J. Kuhn, Hall Crannell, Marco Ripani, S. E. Kuhn, E. Anciant, Roy Thompson, C. Marchand, M. Bellis, J. Shaw, M. R. Niroula, Michael Wood, J. P. Cummings, K. Hafidi, V. S. Serov, L. Elouadrhiri, C. Tur, B. P. Quinn, R. A. Schumacher, G. V. O'Rielly, R. Fatemi, B. Zhao, Kei Moriya, Federico Ronchetti, C. A. Meyer, Victor Mokeev, Z. W. Zhao, J. Hu, M. Khandaker, G. V. Fedotov, M. Kossov, L. Guo, M. Ungaro, B. L. Berman, D. G. Jenkins, Cynthia Marie Hadjidakis, S. Bültmann, T. A. Forest, A. V. Vlassov, I. Popa, I. I. Strakovsky, J. Langheinrich, S. S. Stepanyan, S. A. Philips, A. Coleman, S. Stepanyan, P. Eugenio, B. B. Niczyporuk, H. R. Weller, N. Baillie, M. Battaglieri, R. A. Miskimen, B. McKinnon, P. Dragovitsch, D. P. Weygand, M. Taiuti, J. Pierce, Avraham Klein, Shifeng Chen, Michael Dugger, Kwangsoo Kim, G. Riccardi, N. Pivnyuk, L. M. Qin, J. Napolitano, H. O. Funsten, R. Bradford, J. Yun, D. Cords, Friedrich Klein, M. Osipenko, F. W. Hersman, G. E. Dodge, S. McAleer, F. X. Girod, A. Yegneswaran, C. Butuceanu, R. J. Feuerbach, A. Deur, H. Denizli, Brian Raue, D. Branford, P. V. Degtyarenko, R. De Vita, N. Guler, P. Collins, Marco A. Huertas, M. Mirazita, J. M. Laget, P. L. Cole, M. Guidal, W. K. Brooks, K. Beard, J. Hardie, G. Niculescu, A. V. Skabelin, I. Niculescu, Giovanni Ricco, Atilla Gonenc, M. D. Mestayer, J. J. Manak, H. G. Juengst, P. Coltharp, D. Lawrence, M. Holtrop, J. W. Price, C. Paterson, R. De Masi, E. L. Isupov, P. Nadel-Turonski, M. M. Ito, C. Djalali, R. W. Gothe, Tsutomu Mibe, A.V. Stavinsky, M. Klusman, Michael L. Williams, E. De Sanctis, M. MacCormick, J. T. Goetz, J. Lachniet, D. I. Sober, G. Audit, C. E. Hyde-Wright, E. Polli, M. Guillo, J. D. Kellie, Valeria Muccifora, D. J. Tedeschi, K. Y. Kim, G. Gavalian, S. Tkachenko, V. Batourine, S. Boiarinov, B. M. Preedom, H. Y. Lu, Sergey Kuleshov, I. Bedlinskiy, M. Bektasoglu, N. Benmouna, M. Nozar, Gerard Gilfoyle, E. Wolin, B. Carnahan, Elton Smith, P. Ambrozewicz, D. Sokhan, A. Tkabladze, Nikolay Shvedunov, D. Rowntree, Lorenzo Zana, J. P. Santoro, W. Kim, J. P. Ball, Y. Prok, U. Thoma, R. S. Hakobyan, M. Anghinolfi, D. S. Carman, Sylvain Bouchigny, L. El Fassi, N. Natasha, N. Kalantarians, James Mueller, S. Niccolai, D. G. Crabb, J. Salamanca, Susan Taylor, P. Rossi, J. W C McNabb, D. P. Watts, H. Egiyan, P. D. Rubin, Y. G. Sharabian, V. Crede, J. R. Calarco, B. E. Stokes, G. S. Adams, H. S. Jo, K. Joo, N. A. Baltzell, K. A. Griffioen, N. Markov, Laird Kramer, Y. Ilieva, S. Strauch, G. S. Mutchler, A. I. Ostrovidov, A. C S Lima, D. G. Ireland, Volker D. Burkert, A. S. Biselli, Nicola Bianchi, L. Todor, D. Protopopescu, S. Pozdniakov, M. Garçon, G. Rosner, R. Nasseripour, A. Shafi, K. S. Egiyan, K. Livingston, R. Dickson, K. Mikhailov, S. Barrow, P. Stoler, K. Hicks, J. Donnelly, G. Asryan, O. P. Dzyubak, R. A. Niyazov, M. J. Amaryan, I. Hleiqawi, S. L. Careccia, S. Simionatto, P. Corvisiero, K. L. Giovanetti, B. Asavapibhop, M. Spraker, Larry Weinstein, D. Doughty, D. Heddle, H. Hakobyan, Gerald Feldman, K. Wang, C. Salgado, and Michael Vineyard
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Photon, 010308 nuclear & particles physics, Bremsstrahlung, Hyperon, Observable, Lambda, Polarization (waves), 01 natural sciences, Induced polarization, Nuclear physics, Recoil, 0103 physical sciences, Nuclear Experiment, 010306 general physics
Abstract: Spin transfer from circularly polarized real photons to recoiling hyperons has been measured for the reactions $$\vec\gamma + p \to K^+ + \vec\Lambda$$ and $$\vec\gamma + p \to K^+ + \vec\Sigma^0$$. The data were obtained using the CLAS detector at Jefferson Lab for center-of-mass energies $W$ between 1.6 and 2.53 GeV, and for $$-0.85
Published: 2007

44. Quark-hadron duality in spin structure functionsg1pandg1d

Author: Carlos A. Salgado, M. Amarian, Nikolay Shvedunov, S. Bültmann, M. Guidal, L. Morand, T. A. Forest, P. Dragovitsch, J. Pierce, Avraham Klein, Elton Smith, Gerard Gilfoyle, S. Niccolai, M. Holtrop, K. Livingston, G. E. Dodge, E. Wolin, Hall Crannell, Michael Vineyard, P. V. Degtyarenko, M. Anghinolfi, Hong Lu, J. Hardie, I. Niculescu, James Mueller, B. M. Preedom, D. Lawrence, P. D. Rubin, Y. G. Sharabian, P. Eugenio, R. De Masi, Lorenzo Zana, J. P. Santoro, V. Batourine, H. G. Juengst, J. Langheinrich, S. S. Stepanyan, S. A. Philips, R. Fatemi, B. Carnahan, F. Sabatié, H. S. Jo, D. Doughty, A. V. Vlassov, M. Taiuti, J. P. Ball, Y. Prok, A.V. Stavinsky, L. Elouadrhiri, N. Guler, P. Nadel-Turonski, Tsutomu Mibe, V. Gyurjyan, Federico Ronchetti, R. J. Feuerbach, V. Sapunenko, V. Crede, D. J. Tedeschi, J. P. Cummings, P. Stoler, Dinko Pocanic, D. Heddle, Daniel S. Carman, J. Zhang, B. E. Stokes, D. G. Crabb, S. E. Kuhn, C. E. Hyde-Wright, G. Ricco, J. R. Calarco, H. Denizli, G. Gavalian, N. Baillie, H. Bagdasaryan, J. W. Price, G. V. O'Rielly, I. Bedlinskiy, S. Tkachenko, M. Kossov, C. Tur, Ji Li, S. Barrow, A. Deur, K. Hicks, R. A. Miskimen, B. McKinnon, G. S. Adams, Jeffrey P. Donnelly, N. Benmouna, M. Ripani, Shifeng Chen, M. D. Mestayer, R. DeVita, Sergey Kuleshov, M. Bektasoglu, M. Nozar, E. L. Isupov, Cynthia Marie Hadjidakis, Michael L. Williams, L. M. Qin, J. W C McNabb, K. S. Egiyan, D. Branford, Friedrich Klein, Michael Dugger, P. L. Cole, S. Boiarinov, W. K. Brooks, J. Lachniet, Z. W. Zhao, A. Tkabladze, A. V. Skabelin, Brian Raue, H. O. Funsten, C. Paterson, J. T. Goetz, E. Polli, S. Stepanyan, P. Collins, M. Mirazita, S. A. Morrow, J. M. Laget, Victor Mokeev, J. J. Manak, D. Rowntree, M. Klusman, L. Todor, C. Djalali, K. Mikhailov, Marco A. Huertas, L. Guo, M. Ungaro, D. G. Jenkins, R. S. Hakobyan, Susan Taylor, E. Golovatch, Sylvain Bouchigny, D. Protopopescu, S. Pozdniakov, M. Garçon, C. D. Keith, Kwangsoo Kim, G. Riccardi, H. Egiyan, P. Rossi, P. Ambrozewicz, R. C. Minehart, C. Butuceanu, K. Joo, J. Yun, D. Cords, M. MacCormick, U. Thoma, G. Asryan, I. Hleiqawi, C. A. Meyer, A. Yegneswaran, O. P. Dzyubak, R. A. Niyazov, G. V. Fedotov, M. Bellis, S. L. Careccia, P. Corvisiero, E. De Sanctis, J. Kuhn, Roy Thompson, K. L. Giovanetti, D. I. Sober, M. Guillo, Larry Weinstein, B. B. Niczyporuk, S. McAleer, N. Pivnyuk, J. Napolitano, M. Khandaker, Y. Ilieva, F. X. Girod, D. P. Weygand, Atilla Gonenc, G. Rosner, P. Bosted, R. Nasseripour, P. Coltharp, M. M. Ito, L. C. Smith, B. S. Ishkhanov, A. Cazes, Maryam Moteabbed, Bernhard Mecking, M. R. Niroula, K. V. Dharmawardane, M. Osipenko, K. Beard, W. Kim, M. Battaglieri, G. Niculescu, R. Bradford, K. Lukashin, L. C. Dennis, Laird Kramer, B. E. Bonner, H. Avakian, E. Pasyuk, S. A. Dytman, N. Markov, K. Park, A. I. Ostrovidov, A. C S Lima, D. G. Ireland, Volker D. Burkert, A. S. Biselli, V. P. Kubarovsky, O. Pogorelko, J. Shaw, Michael Wood, K. Hafidi, V. S. Serov, S. Strauch, R. Suleiman, G. S. Mutchler, N. A. Baltzell, K. A. Griffioen, J. D. Kellie, R. W. Gothe, K. Y. Kim, B. Zhao, F. W. Hersman, and R. A. Schumacher
Subjects: Physics, Quantum chromodynamics, Quark, Nuclear and High Energy Physics, Particle physics, Proton, 010308 nuclear & particles physics, Hadron, Duality (optimization), 01 natural sciences, Resonance (particle physics), Nuclear physics, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, Nucleon, Spin-½
Abstract: New measurements of the spin structure functions of the proton and deuteron g1p(x,Q2) and g1d(x,Q2) in the nucleon resonance region are compared with extrapolations of target-mass-corrected next-to-leading-order (NLO) QCD fits to higher energy data. Averaged over the entire resonance region (W 1.7 GeV2. This global duality appears to result from cancellations among the prominent local resonance regions: in particular strong sigma{3/2} contributions in the Delta(1232) region appear to be compensated by strong sigma{1/2} contributions in the resonance region centered on 1.5 GeV. These results are encouraging for the extension of NLO QCD fits to lower W and Q2 than have been used previously.
Published: 2007

45. Measurement of theN→Δ+(1232)Transition at High-Momentum Transfer byπ0Electroproduction

Author: L. C. Smith, B. Zhao, B. S. Ishkhanov, G. E. Dodge, P. V. Degtyarenko, V. Gyurjyan, I. Niculescu, D. Lawrence, M. Battaglieri, M. R. Niroula, J. Zhang, R. Fatemi, H. Bagdasaryan, A. V. Vlassov, L. Todor, T. Lee, F. W. Hersman, C. Marchand, V. Sapunenko, D. Protopopescu, R. A. Schumacher, I. Bedliski, Dinko Pocanic, B. M. Preedom, Inna Aznauryan, S. Pozdniakov, M. Garçon, Michael Wood, C. I O Gordon, S. Bültmann, L. Morand, Avraham Klein, R. Bradford, M. Khandaker, V. S. Serov, J. Lachniet, A. Tkabladze, B. L. Berman, Lorenzo Zana, J. P. Santoro, B. E. Stokes, Alexei V. Klimenko, E. Wolin, J. P. Cummings, S. Strauch, H. Egiyan, S. E. Kuhn, L. M. Qin, J. R. Calarco, G. S. Adams, M. Guidal, K. Park, H. S. Jo, Gerald Feldman, Y. Ilieva, R. A. Miskimen, B. McKinnon, V. P. Kubarovsky, Barry Ritchie, C. Salgado, M. Kossov, G. V. O'Rielly, S. A. Morrow, J. Kuhn, O. Pogorelko, C. Djalali, C. Tur, Baile Zhang, D. Doughty, L. C. Dennis, W. Kim, Rakhsha Nasseripour, N. Markov, B. E. Bonner, D. Branford, J. P. Ball, Y. Prok, H. Avakian, M. Holtrop, G. Niculescu, M. Bellis, Shifeng Chen, Ji Li, M. Mirazita, Latifa Elouadrhiri, J. M. Laget, R. C. Minehart, R. S. Hakobyan, N. A. Baltzell, C. A. Meyer, M. Guillo, E. De Sanctis, V. Batourine, K. Livingston, D. G. Jenkins, M. D. Mestayer, G. V. Fedotov, D. I. Sober, Sylvain Bouchigny, F. Sabatié, P. Ambrozewicz, S. Stepanyan, Michael L. Williams, K. A. Griffioen, Laird Kramer, P. Rossi, D. G. Crabb, N. Guler, S. Boiarinov, W. J. Briscoe, J. T. Goetz, E. Polli, Elton Smith, P. Eugenio, M. Taiuti, E. Pasyuk, D. P. Weygand, P. L. Cole, S. Barrow, S. McAleer, J. Langheinrich, S. S. Stepanyan, M. Anghinolfi, S. A. Philips, James Mueller, H. Denizli, F. X. Girod, U. Thoma, S. A. Dytman, J. D. Kellie, P. D. Rubin, P. Coltharp, Y. G. Sharabian, S. Mehrabyan, A. Cazes, Bernhard Mecking, D. Heddle, A. I. Ostrovidov, K. V. Dharmawardane, I. I. Strakovsky, I. Hleiqawi, G. Rosner, M. M. Ito, J. J. Melone, G. Riccardi, A. Deur, A. V. Skabelin, D. G. Ireland, R. DeVita, J. W C McNabb, S. L. Careccia, Michael Vineyard, Volker D. Burkert, W. K. Brooks, C. Butuceanu, J. W. Price, G. S. Mutchler, B. B. Niczyporuk, K. L. Giovanetti, M. Osipenko, N. Pivnyuk, J. Napolitano, Larry Weinstein, Gerard Gilfoyle, Daniel S. Carman, G. Audit, C. E. Hyde-Wright, M. Bektasoglu, M. Nozar, Victor Mokeev, A. S. Biselli, R. W. Gothe, G. Ricco, M. Amarian, P. Stoler, Friedrich Klein, K. Hicks, Brian Raue, K. S. Egiyan, Cynthia Marie Hadjidakis, Michael Dugger, H. O. Funsten, K. Mikhailov, J. Donnelly, G. Asryan, O. P. Dzyubak, R. A. Niyazov, Federico Ronchetti, P. Corvisiero, G. Gavalian, S. Tkachenko, N. Benmouna, M. Ripani, H. G. Juengst, A.V. Stavinsky, D. J. Tedeschi, S. Niccolai, J. Hardie, L. Guo, M. Ungaro, K. Joo, D. Cords, A. Yegneswaran, and R. J. Feuerbach
Subjects: Physics, Proton, 010308 nuclear & particles physics, Momentum transfer, Scalar (mathematics), Solid angle, General Physics and Astronomy, Resonance, 01 natural sciences, Helicity, Nuclear physics, Amplitude, 0103 physical sciences, Magnetic form factor, 010306 general physics
Abstract: We report a new measurement of the exclusive electroproduction reaction gamma*_p --> pi0_p to explore the evolution from soft nonperturbative physics to hard processes via the Q2 dependence of the magnetic (M1+), electric (E1+), and scalar (S1+) multipoles in the N --> Delta transition. 9000 differential cross section data points cover W from threshold to 1.4 GeV/c2, 4pi center-of-mass solid angle, and Q2 from 3 to 6 GeV2/c2, the highest yet achieved. It is found that the magnetic form factor G^*M decreases with Q2 more steeply than the proton magnetic form factor, the ratio E1+/M1+ is small and negative, indicating strong helicity nonconservation, and the ratio S1+/M1+ is negative, while its magnitude increases with Q2.
Published: 2006

46. Measurement of the deuteron structure functionF2in the resonance region and evaluation of its moments

Author: B. E. Stokes, G. S. Adams, Daniel S. Carman, J. P. Cummings, K. Joo, M. Guillo, G. Audit, C. E. Hyde-Wright, B. M. Preedom, M. Kossov, Susan Taylor, S. Strauch, C. Marchand, H. Egiyan, Silvano Simula, Lorenzo Zana, J. P. Santoro, P. Eugenio, K. Park, M. Taiuti, H. S. Jo, M. Nozar, G. V. O'Rielly, I. Hleiqawi, Alexei V. Klimenko, K. S. Egiyan, S. L. Careccia, J. R. Calarco, W. Kim, Y. Ilieva, K. L. Giovanetti, B. Asavapibhop, Larry Weinstein, M. Khandaker, K. Mikhailov, V. P. Kubarovsky, C. Salgado, Barry Ritchie, M. Battaglieri, D. Doughty, G. Niculescu, R. DeVita, J. W C McNabb, D. Heddle, R. J. Feuerbach, R. A. Schumacher, D. G. Jenkins, A. Empl, N. A. Baltzell, L. C. Smith, B. S. Ishkhanov, E. Wolin, O. Pogorelko, Shifeng Chen, H. G. Juengst, R. Bradford, K. Lukashin, J. J. Melone, E. Golovatch, S. McAleer, K. A. Griffioen, S. A. Morrow, M. Guidal, H. Denizli, C. Djalali, F. X. Girod, J. P. Ball, Y. Prok, A.V. Stavinsky, Ji Li, L. M. Qin, A. V. Skabelin, Marco A. Huertas, Federico Ronchetti, J. Donnelly, G. Rosner, R. Nasseripour, J. D. Kellie, D. G. Crabb, J. T. Goetz, E. Polli, U. Thoma, C. I O Gordon, M. Holtrop, G. Asryan, L. Todor, D. J. Tedeschi, D. Protopopescu, M. D. Mestayer, G. Gavalian, R. C. Minehart, P. Ambrozewicz, L. Elouadrhiri, S. Pozdniakov, M. Garçon, O. P. Dzyubak, A. Cazes, V. Sapunenko, Dinko Pocanic, Sylvain Bouchigny, C. A. Meyer, N. Benmouna, M. Ripani, J. Shaw, G. V. Fedotov, Michael L. Williams, Bernhard Mecking, J. Kuhn, K. V. Dharmawardane, J. W. Price, M. Osipenko, I. Bedlinskiy, M. Klusman, P. Rossi, P. Corvisiero, S. E. Kuhn, S. Boiarinov, S. Bültmann, A. Tkabladze, Michael Wood, D. P. Weygand, A. Deur, Roy Thompson, K. Beard, R. Suleiman, G. Ricco, C. Tur, L. Morand, T. A. Forest, P. Coltharp, V. S. Serov, L. C. Dennis, B. E. Bonner, W. K. Brooks, Cynthia Marie Hadjidakis, G. S. Mutchler, S. Stepanyan, H. Avakian, Michael Dugger, H. O. Funsten, K. Livingston, M. M. Ito, Michael Vineyard, P. Stoler, J. Pierce, Avraham Klein, J. Langheinrich, S. S. Stepanyan, S. A. Philips, B. B. Niczyporuk, Elton Smith, M. Anghinolfi, N. Pivnyuk, J. Napolitano, V. Batourine, S. Mehrabyan, James Mueller, F. Sabatié, P. D. Rubin, E. Pasyuk, P. Dragovitsch, N. Guler, G. Nefedov, K. Hicks, S. A. Dytman, M. Bellis, S. Niccolai, Y. G. Sharabian, G. E. Dodge, J. Hardie, Friedrich Klein, S. Barrow, Brian Raue, P. V. Degtyarenko, Kwangsoo Kim, G. Riccardi, J. Hu, A. Coleman, F. W. Hersman, I. Niculescu, D. Lawrence, C. Butuceanu, Gerard Gilfoyle, R. W. Gothe, R. A. Miskimen, K. Y. Kim, B. McKinnon, D. Branford, M. Mirazita, J. M. Laget, Laird Kramer, N. Baillie, E. De Sanctis, D. I. Sober, R. Fatemi, A. V. Vlassov, T. Lee, J. J. Manak, A. I. Ostrovidov, A. C S Lima, D. G. Ireland, Volker D. Burkert, A. S. Biselli, M. Bektasoglu, J. Lachniet, D. Rowntree, R. S. Hakobyan, P. Nadel-Turonski, P. L. Cole, L. Guo, M. Ungaro, R. A. Niyazov, J. Yun, D. Cords, A. Yegneswaran, V. Gyurjyan, J. Zhang, H. Bagdasaryan, and Victor Mokeev
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Proton, 010308 nuclear & particles physics, Scattering, Hadron, Resonance, 01 natural sciences, Nuclear physics, Cover (topology), 0103 physical sciences, Invariant mass, Operator product expansion, Twist, 010306 general physics
Abstract: Inclusive electron scattering off the deuteron has been measured to extract the deuteron structure function F{sub 2} with the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. The measurement covers the entire resonance region from the quasielastic peak up to the invariant mass of the final-state hadronic system W{approx_equal}2.7 GeV with four-momentum transfers Q{sup 2} from 0.4 to 6 (GeV/c){sup 2}. These data are complementary to previous measurements of the proton structure function F{sub 2} and cover a similar two-dimensional region of Q{sup 2} and Bjorken variable x. Determination of the deuteron F{sub 2} over a large x interval including the quasielastic peak as a function of Q{sup 2}, together with the other world data, permit a direct evaluation of the structure function moments for the first time. By fitting the Q{sup 2} evolution of these moments with an OPE-based twist expansion we have obtained a separation of the leading twist and higher twist terms. The observed Q{sup 2} behavior of the higher twist contribution suggests a partial cancelation of different higher twists entering into the expansion with opposite signs. This cancelation, found also in the proton moments, is a manifestation of the 'duality' phenomenon inmore » the F{sub 2} structure function.« less
Published: 2006

47. Singleπ+electroproduction on the proton in the first and second resonance regions at0.25GeV2<Q2<0.65GeV2

Author: J. Kuhn, Shifeng Chen, R. J. Feuerbach, Roy Thompson, R. W. Gothe, K. Y. Kim, C. Cetina, Y. Kuang, V. Gyurjyan, J. Zhang, E. Anciant, Michael Vineyard, M. Guidal, G. E. Dodge, H. Bagdasaryan, E. Polli, F. W. Hersman, G. Gavalian, K. S. Egiyan, G. Niculescu, Daijin Kim, Min Suk Kim, S. Stepanyan, P. V. Degtyarenko, L. M. Qin, Sylvain Bouchigny, N. Benmouna, M. Ripani, M. Khandaker, K. A. Griffioen, G. Ricco, K. Mikhailov, P. Rossi, M. Holtrop, H. Denizli, Elton Smith, P. Eugenio, M. Taiuti, Philip L. Cole, Ji Li, F. Ronchetti, K. Livingston, E. DeSanctis, G. V. O'Rielly, M. Klusman, M. Anghinolfi, James Mueller, I. Niculescu, Moshe Gai, A. V. Skabelin, E. Wolin, I. G. Aznauryan, I. Hleiqawi, P. D. Rubin, Y. G. Sharabian, J. P. Cummings, D. G. Jenkins, Friedrich Klein, Victor Mokeev, D. Lawrence, S. L. Careccia, S. Simionatto, M. D. Mestayer, Alexei V. Klimenko, K. Sabourov, M. Osipenko, J. Langheinrich, R. DeVita, J. D. Kellie, J. W C McNabb, R. S. Hicks, Brian Raue, J. Lachniet, P. Stoler, J. R. Calarco, L. C. Smith, S. J. Gaff, B. S. Ishkhanov, S. A. Philips, Barry Ritchie, K. Beard, P. Dragovitsch, Dinko Pocanic, M. Kossov, G. T. Goetz, D. Rowntree, Rakhsha Nasseripour, S. McAleer, S. O. Nelson, K. L. Giovanetti, B. Asavapibhop, M. Spraker, Larry Weinstein, L. Guo, M. Ungaro, J. J. Melone, Bernhard Mecking, K. Hicks, S. E. Kuhn, B. Carnahan, F. Sabatié, Latifa Elouadrhiri, W. Kim, K. V. Dharmawardane, D. Doughty, D. Heddle, J. P. Ball, Y. Prok, R. C. Minehart, Cynthia Marie Hadjidakis, C. A. Meyer, B. B. Niczyporuk, J. H. Kelley, S. Niccolai, G. V. Fedotov, C. Tur, Shalev Gilad, Thierry Auger, Michael Dugger, N. Guler, S. Boiarinov, B. M. Preedom, A. Tkabladze, R. S. Hakobyan, O. P. Dzyubak, Daniel S. Carman, Susan Taylor, S. Strauch, G. A. Peterson, H. O. Funsten, M. Eckhause, D. P. Weygand, J. W. Price, J. Hardie, N. Pivnyuk, J. Napolitano, A. Longhi, G. Audit, K. Joo, C. E. Hyde-Wright, R. A. Niyazov, J. Yun, D. Cords, H. Egiyan, A. Yegneswaran, J. P. Santoro, P. Corvisiero, M. Sargsyan, A.V. Stavinsky, N. Baltzel, Hall Crannell, S. A. Morrow, S. Barrow, L. C. Dennis, B. E. Bonner, C. S. Whisnant, C. Djalali, D. J. Tedeschi, C. Marchand, Gerald Feldman, R. A. Schumacher, H. Avakian, J. Hu, M. Nozar, A. Coleman, L. Todor, M. Battaglieri, H. R. Weller, P. Ambrozewicz, K. Wang, C. Salgado, D. Protopopescu, S. Pozdniakov, C. I O Gordon, R. Bradford, K. Lukashin, D. G. Crabb, G. S. Mutchler, Z. L. Zhou, G. Rosner, J. Donnely, A. Shafi, L. Morand, T. A. Forest, W. J. Briscoe, E. Pasyuk, Avraham Klein, S. A. Dytman, G. S. Adams, Y. Ilieva, M. Bellis, K. Park, M. M. Ito, R. Fatemi, A. V. Vlassov, V. P. Kubarovsky, A. Empl, O. Pogorelko, J. J. Manak, Patrick Girard, J. Shaw, Michael Wood, V. S. Serov, Nicola Bianchi, D. I. Sober, L. Y. Murphy, S. Mehrabyan, Kwangsoo Kim, G. Riccardi, C. Butuceanu, Laird Kramer, M. Bektasoglu, D. G. Ireland, Volker D. Burkert, Jing Zhao, A. S. Biselli, R. A. Miskimen, B. McKinnon, H. G. Juengst, D. Branford, M. Mirazita, J. M. Laget, V. Sapunenko, Valeria Muccifora, Gerard Gilfoyle, U. Thoma, M. Guillo, I. I. Strakovsky, and W. K. Brooks
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Proton, 010308 nuclear & particles physics, Hadron, Resonance, Sigma, 01 natural sciences, 7. Clean energy, Helicity, Particle identification, Nuclear physics, 0103 physical sciences, High Energy Physics::Experiment, Neutron, Nuclear Experiment, 010306 general physics, Nucleon
Abstract: The ep {yields} e'pi{sup +}n reaction was studied in the first and second nucleon resonance regions in the 0.25 GeV{sup 2} < Q{sup 2} < 0.65 GeV{sup 2} range using the CLAS detector at Thomas Jefferson National Accelerator Facility. For the first time the absolute cross sections were measured covering nearly the full angular range in the hadronic center-of-mass frame. The structure functions {sigma}{sub TL}, {sigma}{sub TT} and the linear combination {sigma}{sub T} + {epsilon}{sigma}{sub L} were extracted by fitting the {phi}-dependence of the measured cross sections, and were compared to the MAID and Sato-Lee models.
Published: 2006

48. $\eta$' Photoproduction on the Proton for Photon Energies from 1.527 to 2.227 GeV

Author: K. S. Egiyan, I. Hleiqawi, L. C. Smith, B. S. Ishkhanov, R. Fatemi, L. C. Dennis, B. E. Bonner, S. L. Careccia, S. Simionatto, A. V. Vlassov, K. Mikhailov, H. Avakian, V. Mokeev, T. Lee, V. Sapunenko, K. L. Giovanetti, B. Asavapibhop, Bernhard Mecking, K. V. Dharmawardane, Dinko Pocanic, Larry Weinstein, Marco A. Huertas, M. Battaglieri, R. Bradford, K. Lukashin, W. J. Briscoe, R. C. Minehart, C. A. Meyer, S. E. Kuhn, E. Pasyuk, D. Doughty, M. Bellis, G. V. Fedotov, Daniel S. Carman, J. J. Manak, S. A. Dytman, N. A. Baltzell, Sylvain Bouchigny, L. C. Maximon, R. J. Feuerbach, J. Hu, B. M. Preedom, D. Heddle, Laird Kramer, G. Audit, C. E. Hyde-Wright, K. Livingston, J. P. Cummings, K. A. Griffioen, G. Ricco, P. Rossi, M. Guillo, C. Tur, A. Coleman, H. R. Weller, D. P. Weygand, R. A. Schumacher, J. Donnelly, G. Asryan, L. Elouadrhiri, W. Kim, S. McAleer, G. Niculescu, F. X. Girod, O. P. Dzyubak, R. A. Niyazov, V. Batourine, Lorenzo Zana, Shifeng Chen, J. Kuhn, M. Kossov, J. D. Kellie, J. Shaw, I. I. Strakovsky, G. Gavalian, J. P. Santoro, Alexei V. Klimenko, S. Tkachenko, E. De Sanctis, Michael Wood, P. Corvisiero, M. Bektasoglu, E. Anciant, M. Nozar, A. Deur, E. Wolin, S. Bültmann, N. Benmouna, M. Ripani, J. R. Calarco, V. S. Serov, T. A. Forest, B. Carnahan, D. I. Sober, N. Guler, Y. Prok, Barry Ritchie, A. I. Ostrovidov, A. C S Lima, H. S. Jo, Friedrich Klein, S. Stepanyan, Roy Thompson, J. Langheinrich, J. Pierce, Avraham Klein, K. Park, S. S. Stepanyan, M. Khandaker, S. A. Philips, D. G. Ireland, J. T. Goetz, J. P. Ball, G. S. Mutchler, Gerald Feldman, P. Coltharp, W. K. Brooks, F. W. Hersman, Cynthia Marie Hadjidakis, Michael Dugger, K. Wang, Brian Raue, G. E. Dodge, C. Salgado, P. Stoler, H. O. Funsten, V. P. Kubarovsky, N. Baillie, Volker D. Burkert, A. S. Biselli, S. Barrow, M. M. Ito, D. G. Crabb, Elton Smith, H. Denizli, P. V. Degtyarenko, J. W. Price, A. Empl, O. Pogorelko, Valeria Muccifora, Y. Ilieva, P. Eugenio, Susan Taylor, M. Guidal, M. Osipenko, F. Sabatié, S. Strauch, K. Hicks, M. Anghinolfi, M. Taiuti, A. V. Skabelin, P. Dragovitsch, James Mueller, H. Egiyan, K. Beard, D. Lawrence, B. L. Berman, M. Holtrop, P. D. Rubin, Gerard Gilfoyle, Y. G. Sharabian, L. M. Qin, Nicola Bianchi, Federico Ronchetti, Kalvir S. Dhuga, R. A. Miskimen, B. McKinnon, S. Niccolai, G. V. O'Rielly, P. Collins, M. D. Mestayer, Kwangsoo Kim, G. Riccardi, D. Protopopescu, P. Nadel-Turonski, S. Pozdniakov, M. Garçon, J. Hardie, Tsutomu Mibe, C. Butuceanu, A. Shafi, H. G. Juengst, Michael L. Williams, Hall Crannell, C. Marchand, D. G. Jenkins, C. Paterson, M. Klusman, D. Branford, M. Mirazita, J. M. Laget, A.V. Stavinsky, D. J. Tedeschi, S. Boiarinov, R. W. Gothe, I. Bedlinskiy, K. Y. Kim, U. Thoma, Michael Vineyard, B. E. Stokes, G. S. Adams, J. Lachniet, V. Gyurjyan, A. Tkabladze, D. Rowntree, K. Joo, J. Zhang, H. Bagdasaryan, L. Guo, M. Spraker, M. Ungaro, J. Yun, D. Cords, A. Yegneswaran, R. S. Hakobyan, P. L. Cole, G. Rosner, R. Nasseripour, R. DeVita, J. W C McNabb, B. B. Niczyporuk, N. Pivnyuk, J. Napolitano, S. A. Morrow, C. Djalali, P. Ambrozewicz, Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Thomas Jefferson National Accelerator Facility (Jefferson Lab), and CLAS
Subjects: Photon, Proton, eta meson resonances, FOS: Physical sciences, General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, 13.60.Le, 14.20.Gk, 0103 physical sciences, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Spin-½, Physics, Spectrometer, 010308 nuclear & particles physics, Scattering, Coupling (probability), meson photoproduction, photon-proton interactions, Mass spectrum, N channel, High Energy Physics::Experiment, baryon resonances, Atomic physics
Abstract: Differential cross sections for the reaction gamma p -> eta-prime p have been measured with the CLAS spectrometer and a tagged photon beam with energies from 1.527 to 2.227 GeV. The results reported here possess much greater accuracy than previous measurements. Analyses of these data indicate for the first time the coupling of the etaprime N channel to both the S_11(1535) and P_11(1710) resonances, known to couple strongly to the eta N channel in photoproduction on the proton, and the importance of j=3/2 resonances in the process., 6 pages, 3 figures
Published: 2006

49. MEASUREMENT OF DEEPLY VIRTUAL COMPTON SCATTERING WITH A POLARIZED PROTON TARGET

Author: B. E. Bonner, H. Avakian, Marco A. Huertas, D. Doughty, Sylvain Bouchigny, Daniel S. Carman, P. Rossi, S. Barrow, W. J. Briscoe, V. Batourine, C. E. Hyde-Wright, S. A. Dytman, P. Nadel-Turonski, Tsutomu Mibe, Y. Ilieva, B. Carnahan, Sergey Kuleshov, Ji Li, M. Bektasoglu, E. Wolin, M. Ripani, M. Nozar, R. J. Feuerbach, P. Coltharp, A. V. Vlassov, M. D. Mestayer, J. Langheinrich, S. S. Stepanyan, E. Pasyuk, S. A. Philips, M. Khandaker, E. L. Isupov, V. Sapunenko, J. Kuhn, B. McKinnon, J. P. Ball, Y. Prok, M. M. Ito, Michael L. Williams, J. Shaw, Michael Wood, S. Strauch, A. I. Ostrovidov, A. C S Lima, L. Todor, S. Boiarinov, K. Hafidi, D. Protopopescu, Friedrich Klein, D. J. Tedeschi, S. Pozdniakov, M. Garçon, B. L. Berman, H. Y. Lu, D. Branford, M. Guidal, R. W. Gothe, D. G. Ireland, D. G. Crabb, L. M. Qin, Hall Crannell, V. S. Serov, M. Mirazita, J. M. Laget, A. Yegneswaran, Volker D. Burkert, A. S. Biselli, K. Y. Kim, G. Rosner, K. Park, M. Bellis, R. Nasseripour, M. Holtrop, C. Paterson, R. Suleiman, G. S. Mutchler, K.H. Hicks, D. P. Watts, H. Egiyan, N. A. Baltzell, M. Klusman, Michael Vineyard, M. Osipenko, F. Sabatié, Laird Kramer, K. A. Griffioen, B. E. Stokes, P. Stoler, B. M. Preedom, N. Markov, V. Crede, G. S. Adams, K. Beard, L. C. Smith, M. Amarian, Lorenzo Zana, J. P. Santoro, B. S. Ishkhanov, P. Eugenio, Federico Ronchetti, V. P. Kubarovsky, J. R. Calarco, Kalvir S. Dhuga, Nikolay Shvedunov, H. Hakobyan, R. A. Schumacher, M. Taiuti, H. S. Jo, W. Kim, G. Niculescu, Gerard Gilfoyle, M. R. Niroula, M. MacCormick, I. Hleiqawi, S. L. Careccia, J. D. Kellie, U. Thoma, Gerald Feldman, C. Salgado, N. Guler, S. Niccolai, M. Battaglieri, P. Collins, N. Natasha, E. De Sanctis, K. L. Giovanetti, S. Bültmann, L. Morand, Larry Weinstein, T. A. Forest, D. I. Sober, R. Fatemi, S. Stepanyan, N. Baillie, J. Hardie, K. S. Egiyan, R. Bradford, K. Lukashin, J. Pierce, Avraham Klein, B. Zhao, G. E. Dodge, E. Golovatch, K. Mikhailov, P. V. Degtyarenko, P. Bosted, I. Niculescu, D. Lawrence, A. Cazes, Maryam Moteabbed, Bernhard Mecking, R. De Masi, F. W. Hersman, C. D. Keith, K. V. Dharmawardane, S. Tkachenko, J. Donnelly, G. Asryan, O. P. Dzyubak, R. A. Niyazov, Kwangsoo Kim, G. Riccardi, B. A. Raue, Cynthia Marie Hadjidakis, Chaden Djalali, C. Butuceanu, Michael Dugger, H. O. Funsten, P. Corvisiero, H. G. Juengst, G. Gavalian, H. Denizli, N. Benmouna, A.V. Stavinsky, I. Bedlinskiy, A. V. Skabelin, Marc Vanderhaeghen, Barry Ritchie, Victor Mokeev, L. Guo, M. Ungaro, Latifa Elouadrhiri, K. Joo, R. C. Minehart, C. A. Meyer, J. Yun, D. Cords, G. V. Fedotov, D. P. Weygand, J. Zhang, M. Guillo, H. Bagdasaryan, I. I. Strakovsky, A. Deur, W. K. Brooks, J. Lachniet, A. Tkabladze, D. Rowntree, G. V. O'Rielly, R. S. Hakobyan, L. El Fassi, Z. W. Zhao, D. G. Jenkins, B. B. Niczyporuk, P. L. Cole, S. McAleer, F. X. Girod, N. Pivnyuk, D. Heddle, J. Napolitano, Giovanni Ricco, Atilla Gonenc, J. W. Price, O. Pogorelko, R. Miskimen, R. DeVita, J. W C McNabb, S. A. Morrow, P. Ambrozewicz, Shifeng Chen, J. P. Cummings, M. Kossov, I. Popa, J. T. Goetz, E. Polli, V. Gyurjyan, Dinko Pocanic, S. E. Kuhn, C. Tur, Elton Smith, M. Anghinolfi, James Mueller, P. D. Rubin, Y. G. Sharabian, K. Livingston, L. C. Dennis, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), CEA- Saclay (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), CLAS, and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Photon, Proton, Nuclear Theory, media_common.quotation_subject, General Physics and Astronomy, FOS: Physical sciences, Parton, Electron, 01 natural sciences, Asymmetry, High Energy Physics - Experiment, Nuclear physics, Nuclear Theory (nucl-th), High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), GENERALIZED PARTON DISTRIBUTIONS, CLAS, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, NUCLEON, Spin-½, media_common, Physics, 010308 nuclear & particles physics, Compton scattering, High Energy Physics - Phenomenology, High Energy Physics::Experiment, GENERALIZED PARTON DISTRIBUTIONS, NUCLEON, CLAS, 13.60.Fz, 13.60.Hb, 14.20.Dh, Nucleon
Abstract: The longitudinal target-spin asymmetry A_UL for the exclusive electroproduction of high energy photons was measured for the first time in p(e,e'p\gamma). The data have been accumulated at Jefferson Lab with the CLAS spectrometer using 5.7 GeV electrons and a longitudinally polarized NH_3 target. A significant azimuthal angular dependence was observed, resulting from the interference of the Deeply Virtual Compton Scattering and Bethe-Heitler processes. The amplitude of the sin(phi) moment is 0.252 +/- 0.042(stat) +/- 0.020(sys). Theoretical calculations are in good agreement with the magnitude and the kinematic dependence of the target-spin asymmetry, which is sensitive to the generalized parton distributions H and H-tilde., Comment: Modified text slightly, added references
Published: 2006

50. Measurement of the polarized structure functionσLT'for pion electroproduction in the Roper-resonance region

Author: H. Avakian, L. Elouadrhiri, V. Gyurjyan, J. Zhang, H. Bagdasaryan, A.V. Stavinsky, M. Osipenko, V. Batourine, E. Anciant, L. Guo, M. Ungaro, P. Stoler, R. Fatemi, D. J. Tedeschi, I. I. Strakovsky, A. Deur, A. V. Vlassov, K. Joo, N. A. Baltzell, R. A. Niyazov, J. Yun, D. Cords, A. Yegneswaran, M. Bektasoglu, R. A. Schumacher, B. Carnahan, F. Sabatié, W. J. Briscoe, E. Pasyuk, Thierry Auger, K. Beard, S. A. Dytman, I. Bedlinskiy, T. Lee, J. P. Cummings, W. K. Brooks, E. Wolin, K. A. Griffioen, S. Strauch, S. O. Nelson, K. Hicks, M. Kossov, Susan Taylor, R. A. Miskimen, B. McKinnon, H. G. Juengst, J. J. Manak, G. Gavalian, M. Khandaker, J. Lachniet, S. Bueltmann, J. Kuhn, Kalvir S. Dhuga, V. Mokeev, Shifeng Chen, T. A. Forest, J. P. Ball, M. Bellis, Patrick Girard, L. C. Maximon, J. Donnelly, G. Asryan, O. P. Dzyubak, N. Benmouna, M. Ripani, D. Rowntree, H. Egiyan, S. Stepanyan, J. Pierce, Avraham Klein, P. Coltharp, J. Shaw, Michael Wood, J. D. Kellie, M. Guillo, D. Doughty, P. Dragovitsch, Sylvain Bouchigny, Roy Thompson, P. Corvisiero, E. De Sanctis, P. Rossi, J. T. Goetz, D. Protopopescu, G. E. Dodge, E. Polli, D. I. Sober, D. Heddle, R. DeVita, S. Niccolai, Federico Ronchetti, D. G. Ireland, J. Hardie, V. Sapunenko, Dinko Pocanic, K. S. Egiyan, D. Branford, D. G. Crabb, S. Pozdniakov, M. Garçon, J. W C McNabb, W. Kim, M. M. Ito, P. V. Degtyarenko, K. Kim, R. S. Hakobyan, K. Mikhailov, V. S. Serov, G. Niculescu, J. R. Calarco, J. Hu, S. E. Kuhn, M. Mirazita, G. Ricco, S. A. Morrow, J. M. Laget, J. H. Kelley, C. Tur, A. Shafi, L. Farhi, G. S. Mutchler, I. Niculescu, C. Djalali, D. Lawrence, Elton Smith, V. Frolov, M. Battaglieri, K. Park, P. Nadel-Turonski, M. Anghinolfi, P. Eugenio, I. Hleiqawi, James Mueller, R. J. Feuerbach, S. L. Careccia, M. Taiuti, R. Bradford, K. Lukashin, A. Coleman, A. I. Ostrovidov, Friedrich Klein, P. D. Rubin, Y. G. Sharabian, P. Ambrozewicz, S. Simionatto, H. R. Weller, Brian Raue, K. Livingston, Michael Dugger, H. O. Funsten, V. P. Kubarovsky, K. L. Giovanetti, B. Asavapibhop, A. Empl, O. Pogorelko, M. Spraker, Larry Weinstein, G. Rosner, R. Nasseripour, C. Marchand, Volker D. Burkert, A. S. Biselli, Alexei V. Klimenko, M. D. Mestayer, L. C. Smith, S. J. Gaff, Bernhard Mecking, B. S. Ishkhanov, Michael L. Williams, K. V. Dharmawardane, Inna Aznauryan, B. E. Stokes, Y. Prok, B. B. Niczyporuk, G. S. Adams, Laird Kramer, Barry Ritchie, S. Boiarinov, N. Pivnyuk, J. Napolitano, G. Riccardi, N. Guler, N. Baillie, C. Butuceanu, G. A. Peterson, Valeria Muccifora, Gerard Gilfoyle, P. L. Cole, J. Langheinrich, C. Cetina, Michael Vineyard, A. V. Skabelin, S. S. Stepanyan, S. A. Philips, B. M. Preedom, S. Barrow, R. C. Minehart, C. A. Meyer, G. V. Fedotov, Lorenzo Zana, J. P. Santoro, B. L. Berman, M. Guidal, L. M. Qin, A. Tkabladze, Y. Ilieva, D. P. Weygand, H. S. Jo, Gerald Feldman, M. Holtrop, M. Klusman, K. Wang, C. Salgado, Daniel S. Carman, G. Audit, C. E. Hyde-Wright, M. Nozar, Nicola Bianchi, R. W. Gothe, K. Y. Kim, U. Thoma, F. W. Hersman, S. McAleer, F. X. Girod, J. W. Price, G. V. O'Rielly, D. G. Jenkins, K. Sabourov, L. C. Dennis, and B. E. Bonner
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Roper resonance, 010308 nuclear & particles physics, Structure function, Sigma, Electron, Polarization (waves), 01 natural sciences, Pion, Amplitude, 0103 physical sciences, Nuclear Experiment, 010306 general physics, Beam energy
Abstract: The polarized longitudinal-transverse structure function {sigma}{sub LT{sup '}} measures the interference between real and imaginary amplitudes in pion electroproduction and can be used to probe the coupling between resonant and nonresonant processes. We report new measurements of {sigma}{sub LT{sup '}} in the N(1440)(1/2){sup +} (Roper) resonance region at Q{sup 2}=0.40 and 0.65GeV{sup 2} for both the {pi}{sup 0}p and {pi}{sup +}n channels. The experiment was performed at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at a beam energy of 1.515 GeV. Complete angular distributions were obtained and are compared to recent phenomenological models. The {sigma}{sub LT{sup '}}({pi}{sup +}n) channel shows a large sensitivity to the Roper-resonance multipoles M{sub 1-} and S{sub 1-} and provides new constraints on models of resonance formation.
Published: 2005

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