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Sample records for lencioni hearn digenis

  1. Study on Hearn's "Ingwa-Banashi"

    OpenAIRE

    Fujiwara, Mami; 藤原, まみ

    2002-01-01

    Ingwa-Banashi written by Lafcadio Hearn, is a kwaidan which tells of two amputated dead hands clinging to a girl's breasts. This work has been analysed mainly as a story about women's jealousy. However, this story features certain aspects of Hearn's style; fragmentation and body. In this paper I attempt to describe hitherto unanalysed aspects of Hearn's work.

  2. Ireland in the World-System: An Interview with Denis O'Hearn

    Directory of Open Access Journals (Sweden)

    Aidan Beatty

    2016-03-01

    Full Text Available In this interview, Denis O’Hearn presents his views of Ireland’s historical and contemporary status in the capitalist world-system and which countries Ireland could be profitably compared with.  He discusses how Ireland has changed since the publication of his well-known work on "The Atlantic Economy" (2001 and addresses questions related to the European Union and the looming break-up of Britain as well as contemporary Irish politics on both sides of the border. O’Hearn also touches on the current state of Irish academia.

  3. The American Dream in the Great Depression. By Charles R. Hearn. Connecticut and London: Greenwood Press, 1977. The American Dream in the Great Depression. By Charles R. Hearn. Connecticut and London: Greenwood Press, 1977.

    Directory of Open Access Journals (Sweden)

    Randall Huff

    2008-04-01

    Full Text Available Mr. Hearn examines 1 inspirational articles on success; 2 magazine biographies and other articles relating to the myth of success; 3 popular magazine (formula fiction; and 4 the "serious" fiction of the 1920s and 30s to determine the ways in which the depression changed the American myth of the self-made man's social mobility as portrayed in literature. The inspirational success articles in the 1920s presented America as a prosperous utopia with unfettered economic growth within everyone's reach. Many articles of this type continued to be published during the depression, but articles on the cult of personality (as opposed to character and success in non-commercial areas became more numerous. The new genre of how-to-succeed guidebooks provided evidence of a new "outer-directed" personality rather than the inner-directedness of the powerful business magnate. Mr. Hearn examines 1 inspirational articles on success; 2 magazine biographies and other articles relating to the myth of success; 3 popular magazine (formula fiction; and 4 the "serious" fiction of the 1920s and 30s to determine the ways in which the depression changed the American myth of the self-made man's social mobility as portrayed in literature. The inspirational success articles in the 1920s presented America as a prosperous utopia with unfettered economic growth within everyone's reach. Many articles of this type continued to be published during the depression, but articles on the cult of personality (as opposed to character and success in non-commercial areas became more numerous. The new genre of how-to-succeed guidebooks provided evidence of a new "outer-directed" personality rather than the inner-directedness of the powerful business magnate.

  4. Geological interpretation of an airborne gamma-ray spectrometer survey of the Hearne Lake area, Northwest Territories

    International Nuclear Information System (INIS)

    Newton, A.R.; Slaney, V.R.

    1978-01-01

    This study shows how large volumes of airborne data can be displayed in a simple format which provides both mapping and exploration geologists with information not easily obtained from the original data. Eleven lines or part-lines from a gamma-ray survey of the Hearne Lake area were chosen as test lines, and airphotos were used to identify outcrops of each rock type and the distribution of overburden, swamp and water along each line. Geological maps were used to locate the test lines and to provide a listing of the rock types in the area. With this information, it was possible to calculate the average radioelement characteristics of each rock type and to group the rock signatures into a number of rock classes. The techniques described are most usefully applied to those areas where the outcrop is extensive, where some form of geological map already exists, where there are airphotos at scales of 1:30,000 or larger, and where the gamma-ray survey lines are less than 2.5 km apart

  5. Experimental study of the spin structure of the neutron (3He) with low Q2: a relationship between the Bjorken and Gerasimov-Drell-Hearn sum rules

    International Nuclear Information System (INIS)

    Deur, A.

    2000-10-01

    This thesis presents an experimental study of the neutron (and 3 He) spin structure with a particular emphasis in the resonance domain (experiment E94010 that took place in 1997 at Jefferson Lab (TJNAF or formerly CEBAF) in Virginia). A polarized 3 He target was built in order to achieve this study since polarized 3 He nuclei can be seen as polarized neutrons. This target allowed the measurement of the polarized absolute cross sections σ 1/2 (Q 2 , ν) and σ 3/2 (Q 2 , ν) from the inclusive reaction → 3 He( → e, e')X for incident beam energies ranging from 0.86 GeV to 5.07 GeV at a scattering angle of 15.5 deg. The Q 2 evolution of the generalized Gerasimov-Drell-Hearn (GDH) integral on 3 He and on neutron was measured from 0.1 GeV 2 to 1.0 GeV 2 in order to understand the transition between perturbative QCD and non-perturbative QCD. The integration domain in ν (the energy loss of the scattered electron) is from the pion threshold to about 2.5 GeV which covers both the resonance region and the Deep Inelastic Scattering. The high precision of our data constrains the models giving the Q 2 evolution of the generalized GDH integral. The polarized quasi-elastic scattering was also measured. The cross section σ TT (Q 2 , ν) on 3 He and the spin structure functions g 1 3 He (Q 2 , ν) and g 2 3 He (Q 2 , ν) are presented. These data are an indication that the higher-twists are small in our kinematics domain and that the Bloom-Gilman duality seems to hold for the polarized spin structure functions. (author)

  6. Experimental study of the spin structure of the neutron ({sup 3}He) with low Q{sup 2}: a relationship between the Bjorken and Gerasimov-Drell-Hearn sum rules; Etude experimentale de la structure en spin du neutron ({sup 3}He) a bas Q{sup 2}: une connexion entre les regles de somme de Bjorken et Gerasimov-Drell-Hearn

    Energy Technology Data Exchange (ETDEWEB)

    Deur, A

    2000-10-01

    This thesis presents an experimental study of the neutron (and {sup 3}He) spin structure with a particular emphasis in the resonance domain (experiment E94010 that took place in 1997 at Jefferson Lab (TJNAF or formerly CEBAF) in Virginia). A polarized {sup 3}He target was built in order to achieve this study since polarized {sup 3}He nuclei can be seen as polarized neutrons. This target allowed the measurement of the polarized absolute cross sections {sigma}{sub 1/2}(Q{sup 2}, {nu}) and {sigma}{sub 3/2}(Q{sup 2}, {nu}) from the inclusive reaction {sup {sup {yields}}{sup 3}He}({sup {yields}}e, e')X for incident beam energies ranging from 0.86 GeV to 5.07 GeV at a scattering angle of 15.5 deg. The Q{sup 2} evolution of the generalized Gerasimov-Drell-Hearn (GDH) integral on {sup 3}He and on neutron was measured from 0.1 GeV{sup 2} to 1.0 GeV{sup 2} in order to understand the transition between perturbative QCD and non-perturbative QCD. The integration domain in {nu} (the energy loss of the scattered electron) is from the pion threshold to about 2.5 GeV which covers both the resonance region and the Deep Inelastic Scattering. The high precision of our data constrains the models giving the Q{sup 2} evolution of the generalized GDH integral. The polarized quasi-elastic scattering was also measured. The cross section {sigma}{sup TT}(Q{sup 2}, {nu}) on {sup 3}He and the spin structure functions g{sub 1}{sup {sup 3}He}(Q{sup 2}, {nu}) and g{sub 2}{sup {sup 3}He}(Q{sup 2}, {nu}) are presented. These data are an indication that the higher-twists are small in our kinematics domain and that the Bloom-Gilman duality seems to hold for the polarized spin structure functions. (author)

  7. Helicity dependence and contribution to the Gerasimov-Drell-Hearn sum rule of the γ-vectord-vector→πNN reaction channels in the energy region from threshold up to the Δ(1232) resonance

    International Nuclear Information System (INIS)

    Darwish, E. M.; Fernandez-Ramirez, C.; Guerra, E. Moya de; Udias, J. M.

    2007-01-01

    The helicity dependence of the γ-vectord-vector→π - pp,γ-vectord-vector→π + nn, and γ-vectord-vector→π 0 np reaction channels is studied for incident photon energies from threshold up to the Δ(1232) resonance with inclusion of leading πNN effects. The doubly polarized total and differential cross sections for parallel and antiparallel helicity states are predicted. Then the contribution of various channels to the deuteron spin asymmetry and the double polarization E asymmetry is calculated. In addition, the contribution to the Gerasimov-Drell-Hearn (GDH) integral from separate channels is evaluated by explicit integration up to a photon lab energy of 350 MeV. Sizeable effects from final-state interactions, specially for π 0 production, are found. The sensitivity of the results to the elementary pion photoproduction operator is also investigated. Considerable dependence of the results on the elementary amplitude is found. We expect that these results may be useful to interpret the recent measurements from LEGS-BNL, A2, and GDH-MAMI Collaborations

  8. Measurement of the neutron (3He) spin structure functions at low Q2: A connection between the Bjorken and gerasimov-drell-hearn sum rule

    Energy Technology Data Exchange (ETDEWEB)

    Djawotho, Pibero [College of William and Mary, Williamsburg, VA (United States)

    2002-12-01

    This dissertation presents results of experiment E94-010 performed at Jefferson Laboratory (simply known as JLab) in Hall A. The experiment aimed to measure the low Q2 evolution of the Gerasimov-Drell-Hearn (GDH) integral from Q2 = 0.1 to 0.9 GeV2. The GDH sum rule at the real photon point provides an important test of Quantum Chromodynamics (QCD). The low Q2 evolution of the GDH integral contests various resonance models, Chiral Perturbation Theory ({chi} PT) and lattice QCD calculations, but more importantly, it helps us understand the transition between partonic and hadronic degrees of freedom. At high Q2, beyond 1 GeV2, the difference of the GDH integrals for the proton and the neutron is related to the Bjorken sum rule, another fundamental test of QCD. In addition, results of the measurements for the spin structure functions g1 and g2, cross sections, and asymmetries are presented. E94-010 was the first experiment of its kind at JLab. It used a high-pressure, polarized 3He target with a gas pressure of 10 atm and average target polarization of 35%. For the first time, the polarized electron source delivered an average beam polarization of 70% with a beam current of 15 micro A. The limit on the beam current was only imposed by the target. The experiment required six different beam energies from 0.86 to 5.1 GeV. This was the first time the accelerator ever reached 5.1 GeV. Both High-Resolution Spectrometers of Hall A, used in singles mode, were positioned at 15.5 ° each.

  9. Portfolio selection theory and wildlife management | Hearne | ORiON

    African Journals Online (AJOL)

    Portfolio selection theory and wildlife management. ... With a strong commercial incentive driving the increase in game ranching in Southern Africa the need has come for more advanced management tools. ... Some other points of difference from the classical Portfolio Selection problem are also highlighted and discussed.

  10. Seismic Tomography of the Arabian-Eurasian Collision Zone and Surrounding Areas

    Science.gov (United States)

    2010-05-20

    times and procedures for depth determination, Bull. Seism . Soc. Am. 88: 722–743. Gök, R., N. Turkelli, E. Sandvol, D. Seber, and M. Barazangi (2000...C., and M. Wyss (1972). The use of body-wave spectra in the determination of seismic-source parameters, Bull. Seism . Soc. Am. 62, 561-589. Hearn...S. Wang, T. M. Hearn, Z. Xu, H. Liu and Y. Sun (2006), ML Amplitude Tomography in North China, Bull. Seism . Soc. Am., 96, 1560-1566, doi:10.1785

  11. Choosing the best endpoint

    DEFF Research Database (Denmark)

    Christensen, Erik

    2008-01-01

    Design and endpoints of clinical trials in hepatocellular carcinoma. Llovet JM, Di Bisceglie AM, Bruix J, Kramer BS, Lencioni R, Zhu AX, Sherman M, Schwartz M, Lotze M, Talwalkar J, Gores GJ; for the Panel of Experts in HCC-Design Clinical Trials. The design of clinical trials in hepatocellular c...... and maximize the cost-benefit ratio of trial execution. Design and conduct of phase 3 trials should be coordinated by centers with appropriate expertise in HCC. [Abstract reproduced by permission of J Natl Cancer Inst 2008;100:698-711.] Link to free abstract at: (http...

  12. Clipboard Eppin: A candidate male contraceptive vaccine?

    Indian Academy of Sciences (India)

    Unknown

    O'Hearn P, Bambra C, Isahakia M and Goldberg E 1995 Reversible contraception in female baboons immunized with a synthetic epitope of sperm specific LDH; Biol. Reprod. 52 331–339. O'Rand M G, Widgren E E, Sivashanmugam P, Richardson R T, Hall S H, French F S, VandeVoort C A,. Ramachandra S G, Ramesh V ...

  13. Self-Reporting MBA Key Experience Assessment: Evidence from Lincoln University

    Science.gov (United States)

    Tailab, Mohamed; Guerra, Michael

    2017-01-01

    This paper empirically provides an innovative way of thinking about the MBA program at Lincoln University (hereafter LU) by giving students an opportunity to rate their work experience based on how they currently see themselves. This manuscript develops the instrument prepared by McMillan & Hearn (2004) by creating a questionnaire including 21…

  14. Education

    Science.gov (United States)

    2003-01-01

    Frank Sosa, Dept. of the Air Force Col Juan Urbano , Peruvian Army Dr. Francis A’Hearn, Faculty Prof. William Mayall, Faculty COL Mark McGuire...Germany House of Commons, Parliamentary Undersecretary State for Education, England Ministry of Science, Research, and Art , Stuttgart, Germany...markets. Fifty percent of the elementary market is composed of reading and language arts . Mathematics and a combination social sciences/science and

  15. Identification of a coumarin based antihistamine as an anti filoviral entry inhibitor

    Science.gov (United States)

    2017-06-20

    similar glycosaminoglycans(O’Hearn et al., 2015; Salvador et al., 2013), or C-type lectin family members like LSECtin (liver and lymph node ... node -specific ICAM-3 grabbing nonintegrin), mannose-binding lectin, and hMGL (human macrophage galactose- and N- TR-17-126 Distribution Statement A...antihistamines exhibit potent inhibitory activity against both pseudotyped EBOV and MARV in adenocarcinomic human alveolar basal epithelial cells (A549). More

  16. Extending the Soar Cognitive Architecture

    Science.gov (United States)

    2007-07-01

    interaction between amygdala and hypothalamus . This work is currently being written up for publication (Hearn and Granger, in prep) and it is...initiated arm movements. The Journal of Neurophysiology 63 (1990), 592-606. Romo R, Schultz W. Dopamine neurons of the monkey midbrain...contingencies of responses to active touch during self-initiated arm movements. The Journal of Neurophysiology 63 (1990), 592-606. Schultz W. Responses of

  17. Combination of BTrackS and Geri-Fit as a targeted approach for assessing and reducing the postural sway of older adults with high fall risk

    OpenAIRE

    Goble,Daniel; Hearn,Mason; Baweja,Harsimran

    2017-01-01

    Daniel J Goble, Mason C Hearn, Harsimran S Baweja School of Exercise and Nutritional Sciences, College of Health and Human Services, San Diego State University, San Diego, CA, USA Abstract: Atypically high postural sway measured by a force plate is a known risk factor for falls in older adults. Further, it has been shown that small, but significant, reductions in postural sway are possible with various balance exercise interventions. In the present study, a new low-cost force-plate technolo...

  18. Comparison of the Composition of the Tempel 1 Ejecta to the Dust in Comet C/Hale-Bopp 1995 O1 and YSO HD 100546

    Science.gov (United States)

    2007-01-01

    aggregated from loosely held fractal particles Mg-, Fe-, and Ca-rich pyroxenes were found. Glassy sill- into individual suh- fractal components (A’Hearn er al...planetary geology . The silicate evidence implies that the dust in TI has been most The most abundant oxidant available was instead sulfur, ob- heavily...59D,579-597. graphs on Geology and Geophysics, vol. 11. Clarendon Press Oxford. And Harker, DIL, Woodward, C.E, Wooden, DRi, 2005. The dust grains fronm

  19. Environmental Change & Fragile States Early Warning and Intervention

    Science.gov (United States)

    2011-05-12

    Fragile States Early Warning and Intervention 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e...position of the Department of the Army, Department of Defense, or the U.S. government Environmental Change & Fragile States Early Warning and... Intervention Steven Hearne, P.E., Senior Fellow Army Environmental Policy Institute (AEPI) Jeremey Alcorn, Research Fellow Logistics Management Institute (LMI

  20. Keck i LWS Mid-Ir Images and Photometry of 9P/TEMPEL 1

    Science.gov (United States)

    Fernandez, Y. R.; Lisse, C. M.; A'Hearn, M. F.; Belton, M. J. S.

    2010-01-01

    This data set contains raw and reduced mid-infrared images and photometry of comet 9P/Tempel 1, the target of the Deep Impact mission. Images were acquired on the night of 21 August 2000, about 7.5 months after perihelion, by Y. Fernandez, C. Lisse, M. A'Hearn and M. Belton using the Long Wavelength Spectrometer instrument at the Keck I telescope.

  1. Modelling of nitric acid production in the Advanced Cold Process Canister due to irradiation of moist air

    International Nuclear Information System (INIS)

    Henshaw, J.

    1994-01-01

    This report summarises the work performed for SKB of Sweden on the modelling of nitric acid production in the gaseous environment of the Advanced Cold Process Canister (ACPC). The model solves the simultaneous chemical rate equations describing the radiation chemistry of He/Ar/N 2 /O 2 /H 2 O gas mixture, involving over 200 chemical reactions. The amount of nitric acid produced as a function of time for typical ACPC conditions has been calculated using the model and the results reported. 11 refs, 11 figs, 1 tab

  2. Report of Hero Board: Proceedings of the Board of Officers Convened by the Following Order, General Headquarters, American Expeditionary Forces, Office, Chief of Artillery

    Science.gov (United States)

    1985-01-01

    Burr, Edward Bush, H. M., Davis, J. R., Hearn, C. C., Henderson, A. I., McVicker , Lansing, Price, W. G., Jr., Sarratt, E. 0., Verbeck, G. F...battery O.P. hunting trouble. Gun Section out to one Gun Crew. The 5th section to be composed of one line sergeant, one corporal, and 7 men - all...whether or not it in no way effects the desirability of its battery change. - Lensing McVicker , 1st Lieut., 7th F.A. If the present Infantry

  3. Monitoring environmental hazards and public health

    Science.gov (United States)

    Showstack, Randy

    Saying that no national system exists to monitor public health problems linked to environmental hazards, former U.S. Senator Lowell Weicker, Jr., announced on May 11 the launch of a Pew Charitable Trusts blue ribbon panel to focus on this issue.The panel, which includes representatives from academia and health care organizations, will focus on how the United States tracks diseases and recommend ways to fill data gaps; review what tools are needed to improve disease tracking; and focus on children's health issues, such as asthma, childhood cancer, and birth defects that may be linked to the environment, according to Pew Environmental Health Commission Executive Director Shelley Hearne.

  4. Separation Logic

    DEFF Research Database (Denmark)

    Reynolds, John C.

    2002-01-01

    In joint work with Peter O'Hearn and others, based on early ideas of Burstall, we have developed an extension of Hoare logic that permits reasoning about low-level imperative programs that use shared mutable data structure. The simple imperative programming language is extended with commands (not...... with the inductive definition of predicates on abstract data structures, this extension permits the concise and flexible description of structures with controlled sharing. In this paper, we will survey the current development of this program logic, including extensions that permit unrestricted address arithmetic...

  5. Local Reasoning about Programs that Alter Data Structures

    DEFF Research Database (Denmark)

    O'Hearn, Peter W.; Reynolds, John Clifton; Yang, Hongseok

    2001-01-01

    We describe an extension of Hoare's logic for reasoning about programs that alter data structures. We consider a low-level storage model based on a heap with associated lookup, update, allocation and deallocation operations, and unrestricted address arithmetic. The assertion language is based....... Through these and a number of examples we show that the formalism supports local reasoning: A speci-cation and proof can concentrate on only those cells in memory that a program accesses. This paper builds on earlier work by Burstall, Reynolds, Ishtiaq and O'Hearn on reasoning about data structures....

  6. Polarized photoproduction from nuclear targets with arbitrary spin and relation to deep inelastic scattering

    International Nuclear Information System (INIS)

    Hoodbhoy, P.; Massachusetts Inst. of Tech., Cambridge; Quaid-i-Azam Univ., Islamabad

    1990-01-01

    Inclusive photo-production from polarized targets of arbitrary spin is analyzed by using multipoles. The Drell-Hearn-Gerasimov sum rule, which was originally fromulated for spin-1/2 targets, is generalized to all spins and multipoles, and shown to have some interesting consequences. Measurements to test the new rules, or to derive nuclear structure information from them, could be incorporated into existing plans at electron accelerator facilities. Finally, the possible relevance of these generalized sum rules to sum rules measurable in polarized lepton-polarized target deep inelastic inclusive scattering is discussed. (orig.)

  7. Optical low-dispersion spectroscopic observations of Comet 103P/Hartley 2 at Koyama Astronomical Observatory during the EPOXI flyby

    Science.gov (United States)

    Shinnaka, Yoshiharu; Kawakita, Hideyo; Kobayashi, Hitomi; Naka, Chiharu; Arai, Akira; Arasaki, Takayuki; Kitao, Eiji; Taguchi, Gaku; Ikeda, Yuji

    2013-02-01

    We performed low-dispersion spectroscopic observations of Comet 103P/Hartley 2 in optical wavelengths using the LOSA/F2 mounted on the 1.3 m-Araki telescope at Koyama Astronomical Observatory on UT 2010 November 4 during the close approach of the Deep Impact spacecraft to the nucleus of Comet 103P/Hartley 2 in the EPOXI mission flyby. Our observations have revealed the chemistry of the coma at optical wavelengths; including CN, C3, C2 and NH2 along with H2O from [OI] emission at 6300 Å. Resultant mixing ratios of these radicals put the comet into the normal group in chemical composition. The mixing ratios with respect to H2O obtained in our observations are basically consistent with the previous optical spectro-photometric observations of Comet 103P/Hartley 2 in 1991 by A'Hearn et al. (A'Hearn, M.F., Millis, R.L., Schleicher, D.G., Osip, D.J., Birch, P.V. [1995]. Icarus 118, 223-270), the optical spectroscopic observations in 1998 by Fink (Fink, U. [2009]. Icarus 201, 311-334) and also consistent with the observations on UT 2010 October 27 and 29 by Lara et al. (Lara, L.M., Lin, Z.-Y., Meech, K. [2011]. Astron. Astrophys. 532, A87) (but only for the ratio relative to CN).

  8. La métropolisation parisienne : particularités et généralités O processo de metropolização parisiense: as particularidades e os processos gerais Paris metropolization process: the particularities and the general processes

    Directory of Open Access Journals (Sweden)

    Glória da Anunciação Alves

    2012-03-01

    Full Text Available Parler du phénomène métropolitain aujourd’hui, en plein XXIe siècle, suppose que l’on aille au-delà des phénomènes de croissance et de multiplication qui sont en général constants dans les grandes agglomérations urbaines. La métropolisation de l’espace est un processus qui peut également se caractériser aujourd’hui par la discontinuité territoriale qui articule les villes à partir de méthodes de production, grâce à l’existence de réseaux (techniques et informationnels permettant de relier les espaces non continus. Selon Lencioni (2003, la zone d'influence et les articulations de la métropole instaurent une limite à cela.Mais discuter de la métropolisation, c’est aussi aller au-delà de la croissance et de la multiplication des agglomérations et des richesses. C’est essayer de comprendre la contradiction présente dans cette relation et dans les lieux qui configurent la métropole traditionnelle, c’est-à-dire, sa continuité territoriale. C'est aussi étudier l’accroissement de la pauvreté et de la distinction sociale et spatiale. Avec l’expansion métropolitaine naissent, avec ou sans l’aval des pouvoirs publics, des zones périphériques qui sont nécessaires pour la croissance de la richesse métropolitaine.La question du phénomène métropolitain se pose aujourd'hui d'un point de vue institutionnel. Le projet « Grand Paris » propose d’agir pour promouvoir l’institutionnalisation d’une future métropolisation parisienne qui, selon l'État, est nécessaire pour que Paris continue à faire partie des métropoles internationales attirant des investissements au niveau mondial.Mais que signifie institutionnaliser la métropole ? C’est d'une part, mettre officiellement en pratique un projet national de compétitivité internationale (à l’échelle mondiale et de l’autre, c’est braquer les projecteurs sur les conflits et les rapports Paris-banlieues (à l’échelle locale et r

  9. GEM photomultiplier operation in CF sub 4

    CERN Document Server

    Breskin, Amos; Chechik, R

    2002-01-01

    The properties of a 3-GEM (Gas Electron Multiplier) element photomultiplier, with a semitransparent CsI photocathode and CF sub 4 gas filling, are presented. Compared to other gas mixtures, such as CH sub 4 , Ar/CH sub 4 , Ar/N sub 2 and He/Ar/N sub 2 , CF sub 4 has superior performance: the highest gain, approaching 10 sup 7 , the fastest, 8 ns wide signal and the lowest photoelectron backscattering; the latter allows to reach photocathode quantum efficiency values approaching that in vacuum. The time resolution of the multi-GEM photomultiplier for single photoelectrons was measured to be 2 ns. These properties are of high relevance for applications in Cherenkov detectors and in tracking devices.

  10. Measurement of the Q^{2} Dependence of the Deuteron Spin Structure Function g_{1} and its Moments at Low Q^{2} with CLAS.

    Science.gov (United States)

    Adhikari, K P; Deur, A; El Fassi, L; Kang, H; Kuhn, S E; Ripani, M; Slifer, K; Zheng, X; Adhikari, S; Akbar, Z; Amaryan, M J; Avakian, H; Ball, J; Balossino, I; Barion, L; Battaglieri, M; Bedlinskiy, I; Biselli, A S; Bosted, P; Briscoe, W J; Brock, J; Bültmann, S; Burkert, V D; Thanh Cao, F; Carlin, C; Carman, D S; Celentano, A; Charles, G; Chen, J-P; Chetry, T; Choi, S; Ciullo, G; Clark, L; Cole, P L; Contalbrigo, M; Crede, V; D'Angelo, A; Dashyan, N; De Vita, R; De Sanctis, E; Defurne, M; Djalali, C; Dodge, G E; Drozdov, V; Dupre, R; Egiyan, H; El Alaoui, A; Elouadrhiri, L; Eugenio, P; Fedotov, G; Filippi, A; Ghandilyan, Y; Gilfoyle, G P; Golovatch, E; Gothe, R W; Griffioen, K A; Guidal, M; Guler, N; Guo, L; Hafidi, K; Hakobyan, H; Hanretty, C; Harrison, N; Hattawy, M; Heddle, D; Hicks, K; Holtrop, M; Hyde, C E; Ilieva, Y; Ireland, D G; Isupov, E L; Jenkins, D; Jo, H S; Johnston, S C; Joo, K; Joosten, S; Kabir, M L; Keith, C D; Keller, D; Khachatryan, G; Khachatryan, M; Khandaker, M; Kim, W; Klein, A; Klein, F J; Konczykowski, P; Kovacs, K; Kubarovsky, V; Lanza, L; Lenisa, P; Livingston, K; Long, E; MacGregor, I J D; Markov, N; Mayer, M; McKinnon, B; Meekins, D G; Meyer, C A; Mineeva, T; Mirazita, M; Mokeev, V; Movsisyan, A; Munoz Camacho, C; Nadel-Turonski, P; Niculescu, G; Niccolai, S; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardo, L; Paremuzyan, R; Park, K; Pasyuk, E; Payette, D; Phelps, W; Phillips, S K; Pierce, J; Pogorelko, O; Poudel, J; Price, J W; Prok, Y; Protopopescu, D; Raue, B A; Rizzo, A; Rosner, G; Rossi, P; Sabatié, F; Salgado, C; Schumacher, R A; Sharabian, Y G; Shigeyuki, T; Simonyan, A; Skorodumina, Iu; Smith, G D; Sparveris, N; Sokhan, D; Stepanyan, S; Strakovsky, I I; Strauch, S; Sulkosky, V; Taiuti, M; Tan, J A; Ungaro, M; Voutier, E; Wei, X; Weinstein, L B; Zhang, J; Zhao, Z W

    2018-02-09

    We measured the g_{1} spin structure function of the deuteron at low Q^{2}, where QCD can be approximated with chiral perturbation theory (χPT). The data cover the resonance region, up to an invariant mass of W≈1.9  GeV. The generalized Gerasimov-Drell-Hearn sum, the moment Γ_{1}^{d} and the spin polarizability γ_{0}^{d} are precisely determined down to a minimum Q^{2} of 0.02  GeV^{2} for the first time, about 2.5 times lower than that of previous data. We compare them to several χPT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the χPT domain.

  11. Final-state interaction in spin asymmetry and GDH sum rule for incoherent pion production on the deuteron

    Energy Technology Data Exchange (ETDEWEB)

    Darwish, E.M.; Arenhoevel, H.; Schwamb, M. [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, D-55099, Mainz (Germany)

    2003-07-01

    The contribution of incoherent single-pion photoproduction to the spin response of the deuteron, i.e., the asymmetry of the total photoabsorption cross-section with respect to parallel and antiparallel spins of photon and deuteron, is calculated over the region of the {delta}-resonance with inclusion of final-state NN and {pi}N rescattering. Sizeable effects, mainly from NN rescattering, are found leading to an appreciable reduction of the spin asymmetry. Furthermore, the contribution to the Gerasimov-Drell-Hearn integral is explicitly evaluated by integration up to a photon energy of 550 MeV. Final-state interaction reduces the value of the integral to about half of the value obtained for the pure impulse approximation. (orig.)

  12. Measurement of the Q2 Dependence of the Deuteron Spin Structure Function g1 and its Moments at Low Q2 with CLAS

    Science.gov (United States)

    Adhikari, K. P.; Deur, A.; El Fassi, L.; Kang, H.; Kuhn, S. E.; Ripani, M.; Slifer, K.; Zheng, X.; Adhikari, S.; Akbar, Z.; Amaryan, M. J.; Avakian, H.; Ball, J.; Balossino, I.; Barion, L.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A. S.; Bosted, P.; Briscoe, W. J.; Brock, J.; Bültmann, S.; Burkert, V. D.; Thanh Cao, F.; Carlin, C.; Carman, D. S.; Celentano, A.; Charles, G.; Chen, J.-P.; Chetry, T.; Choi, S.; Ciullo, G.; Clark, L.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Defurne, M.; Djalali, C.; Dodge, G. E.; Drozdov, V.; Dupre, R.; Egiyan, H.; El Alaoui, A.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Filippi, A.; Ghandilyan, Y.; Gilfoyle, G. P.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guler, N.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Heddle, D.; Hicks, K.; Holtrop, M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Isupov, E. L.; Jenkins, D.; Jo, H. S.; Johnston, S. C.; Joo, K.; Joosten, S.; Kabir, M. L.; Keith, C. D.; Keller, D.; Khachatryan, G.; Khachatryan, M.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F. J.; Konczykowski, P.; Kovacs, K.; Kubarovsky, V.; Lanza, L.; Lenisa, P.; Livingston, K.; Long, E.; MacGregor, I. J. D.; Markov, N.; Mayer, M.; McKinnon, B.; Meekins, D. G.; Meyer, C. A.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Movsisyan, A.; Munoz Camacho, C.; Nadel-Turonski, P.; Niculescu, G.; Niccolai, S.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Pappalardo, L.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Payette, D.; Phelps, W.; Phillips, S. K.; Pierce, J.; Pogorelko, O.; Poudel, J.; Price, J. W.; Prok, Y.; Protopopescu, D.; Raue, B. A.; Rizzo, A.; Rosner, G.; Rossi, P.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Sharabian, Y. G.; Shigeyuki, T.; Simonyan, A.; Skorodumina, Iu.; Smith, G. D.; Sparveris, N.; Sokhan, D.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sulkosky, V.; Taiuti, M.; Tan, J. A.; Ungaro, M.; Voutier, E.; Wei, X.; Weinstein, L. B.; Zhang, J.; Zhao, Z. W.; CLAS Collaboration

    2018-02-01

    We measured the g1 spin structure function of the deuteron at low Q2, where QCD can be approximated with chiral perturbation theory (χ PT ). The data cover the resonance region, up to an invariant mass of W ≈1.9 GeV . The generalized Gerasimov-Drell-Hearn sum, the moment Γ1d and the spin polarizability γ0d are precisely determined down to a minimum Q2 of 0.02 GeV2 for the first time, about 2.5 times lower than that of previous data. We compare them to several χ PT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the χ PT domain.

  13. The Spin Structure of the Neutron and 3HE:. AN Overview of the Jlab Experiments in Hall a

    Science.gov (United States)

    Meziani, Z.-E.

    2001-02-01

    I shall discuss three experiments which form part of a comprehensive physics program aimed at the study of the spin structure of the neutron using a polarized 3He target and a polarized beam at JLab in Hall A. Results from the first experiment performed to evaluate the Gerasimov-Drell-Hearn (GDH) extended sum rule are presented and future approved measurements are discussed. The main goal of these experiments is to bridge our understanding of the strong interaction in the large Q2 regime where quarks and gluons are the relevant degrees of freedom to the low Q2 regime where constituent quarks and mesons seem to be more adequate for a description of the nucleon properties.

  14. Measurement of the Proton and Deuteron Spin Structure Function g1 in the Resonance Region

    International Nuclear Information System (INIS)

    Abe, K.; Akagi, T.; Perry Anthony; Antonov, R.; Arnold, R.G.; Todd Averett; Band, H.R.; Bauer, J.M.; Borel, H.; Peter Bosted; Vincent Breton; Button-Shafer, J.; Jian-Ping Chen; T.E. Chupp; J. Clendenin; C. Comptour; K.P. Coulter; G. Court; Donald Crabb; M. Daoudi; Donal Day; F.S. Dietrich; James Dunne; H. Dutz; R. Erbacher; J. Fellbaum; Andrew Feltham; Helene Fonvieille; Emil Frlez; D. Garvey; R. Gearhart; Javier Gomez; P. Grenier; Keith Griffioen; S. Hoeibraten; Emlyn Hughes; Charles Hyde-Wright; J.R. Johnson; D. Kawall; Andreas Klein; Sebastian Kuhn; M. Kuriki; Richard Lindgren; T.J. Liu; R.M. Lombard-Nelsen; Jacques Marroncle; Tomoyuki Maruyama; X.K. Maruyama; James Mccarthy; Werner Meyer; Zein-Eddine Meziani; Ralph Minehart; Joseph Mitchell; J. Morgenstern; Gerassimos Petratos; R. Pitthan; Dinko Pocanic; C. Prescott; R. Prepost; P. Raines; Brian Raue; D. Reyna; A. Rijllart; Yves Roblin; L. Rochester; Stephen Rock; Oscar Rondon-Aramayo; Ingo Sick; Lee Smith; Tim Smith; M. Spengos; F. Staley; P. Steiner; S. St. Lorant; L.M. Stuart; F. Suekane; Z.M. Szalata; Huabin Tang; Y. Terrien; Tracy Usher; Dieter Walz; Frank Wesselmann; J.L. White; K. Witte; C. Young; Brad Youngman; Haruo Yuta; G. Zapalac; Benedikt Zihlmann; Zimmermann, D.

    1997-01-01

    We have measured the proton and deuteron spin structure functions g 1 p and g 1 d in the region of the nucleon resonances for W 2 2 and Q 2 ≅ 0.5 and Q 2 ≅ 1.2 GeV 2 by inelastically scattering 9.7 GeV polarized electrons off polarized 15 NH 3 and 15 ND 3 targets. We observe significant structure in g 1 p in the resonance region. We have used the present results, together with the deep-inelastic data at higher W 2 , to extract Γ(Q 2 ) (triple b ond) ∫ 0 1 g 1 (x,Q 2 ) dx. This is the first information on the low-Q 2 evolution of Gamma toward the Gerasimov-Drell-Hearn limit at Q 2 = 0

  15. The Spin Structure of the Proton in the Resonance Region

    Energy Technology Data Exchange (ETDEWEB)

    Fatemi, Renee H. [Univ. of Virginia, Charlottesville, VA (United States)

    2002-01-01

    Inclusive double spin asymmetries have been measured for $\\vec{p}$($\\vec{e}$,e') using the CLAS detector and a polarized 15NH3 target at Jefferson Lab in 1998. The virtual photon asymmetry A1, the longitudinal spin structure function, g1 (x, Q2), and the first moment Γ$1\\atop{p}$, have been extracted for a Q2 range of 0.15-2.0 GeV2. These results provide insight into the low Q2 evolution of spin dependent asymmetries and structure functions as well as the transition of Γ$1\\atop{p}$ from the photon point, where the Gerasimov, Drell and Hearn Sum Rule is expected to be satisfied, to the deep inelastic region.

  16. Dissecting the Hadronic Contributions to (g -2 )μ by Schwinger's Sum Rule

    Science.gov (United States)

    Hagelstein, Franziska; Pascalutsa, Vladimir

    2018-02-01

    The theoretical uncertainty of (g -2 )μ is currently dominated by hadronic contributions. In order to express those in terms of directly measurable quantities, we consider a sum rule relating g -2 to an integral of a photoabsorption cross section. The sum rule, attributed to Schwinger, can be viewed as a combination of two older sum rules: Gerasimov-Drell-Hearn and Burkhardt-Cottingham. The Schwinger sum rule has an important feature, distinguishing it from the other two: the relation between the anomalous magnetic moment and the integral of a photoabsorption cross section is linear, rather than quadratic. The linear property makes it suitable for a straightforward assessment of the hadronic contributions to (g -2 )μ . From the sum rule, we rederive the Schwinger α /2 π correction, as well as the formula for the hadronic vacuum-polarization contribution. As an example of the light-by-light contribution, we consider the single-meson exchange.

  17. FORMA, DIMENSÕES E FEIÇÕES GERAIS DA TERRA: da Antiguidade ao Renascimento

    Directory of Open Access Journals (Sweden)

    Francisco de Assis Veloso Filho

    2010-01-01

    Full Text Available Este ensayo tiene como objetivo abarcar una visión general de las discusiones y de las representaciones sobre la forma, las dimensiones y los rasgos generales de la Tierra, desde la antigüedad hasta el fi nal de la Edad Media, de la época del Renacimiento en la Europa. En términos metodológicos, la investigación emplea una visión a largo plazo elaborada en el abordaje de Lacoste (1988 y comprende una revisión de la literatura que consideró obras como la Geografía de Ptolomeu (PTOLOMEU, 1991, estudios de referencia en la temática, como Kimble (2006 y manuales de historia del pensamiento geográfi co, como Lencioni (2003. Los conocimientos geográfi cos de los griegos, añadidos de las contribuciones de los romanos, fueron sistematizados por Estrabão y por Ptolomeu en el inicio de la era cristiana. Las obras de estes geógrafos llegaron a la posterioridad, siendo consideradas por los bizantinos, tras la caída de Roma, y por los árabes, después de la expansión del Islamismo, en el siglo VII. Esa tradición clásica fue rescatada en el Renacimiento Europeo. La fusión de elementos de esa tradición con interpretaciones de inspiración cristiana, con la geografía de los árabes, con la tradición de la cartografía náutica (cartas portulano y las navegaciones y descubrimientos geográficos de la primera mitad del siglo XV empezaron una fase de transición en ese campo de conocimiento, en que la Geografía de Ptolomeu comenzó a ser derribada por nuevos intentos de descripción y representación general del mundo.

  18. Sum rule measurements of the spin-dependent compton amplitude (nucleon spin structure at Q2 = 0)

    International Nuclear Information System (INIS)

    Babusci, D.; Giordano, G.; Baghaei, H.; Cichocki, A.; Blecher, M.; Breuer, M.; Commeaux, C.; Didelez, J.P.; Caracappa, A.; Fan, Q.

    1995-01-01

    Energy weighted integrals of the difference in helicity-dependent photo-production cross sections (σ 1/2 - σ 3/2 ) provide information on the nucleon's Spin-dependent Polarizability (γ), and on the spin-dependent part of the asymptotic forward Compton amplitude through the Drell-Hearn-Gerasimov (DHG) sum rule. (The latter forms the Q 2 =0 limit of recent spin-asymmetry experiments in deep-inelastic lepton-scattering.) There are no direct measurements of σ 1/2 or σ 3/2 , for either the proton or the neutron. Estimates from current π-photo-production multipole analyses, particularly for the proton-neutron difference, are in good agreement with relativistic-l-loop Chiral calculations (χPT) for γ but predict large deviations from the DHG sum rule. Either (a) both the 2-loop corrections to the Spin-Polarizability are large and the existing multipoles are wrong, or (b) modifications to the Drell-Hearn-Gerasimov sum rule are required to fully describe the isospin structure of the nucleon. The helicity-dependent photo-reaction amplitudes, for both the proton and the neutron, will be measured at LEGS from pion-threshold to 470 MeV. In these double-polarization experiments, circularly polarized photons from LEGS will be used with SPHICE, a new frozen-spin target consisting of rvec H · rvec D in the solid phase. Reaction channels will be identified in SASY, a large detector array covering about 80% of 4π. A high degree of symmetry in both target and detector will be used to minimize systematic uncertainties

  19. The Spin Structure of 3He and the Neutron at Low Q2: A Measurement of the Generalized GDH Integrand

    Energy Technology Data Exchange (ETDEWEB)

    Sulkosky, Vincent [College of William and Mary, Williamsburg, VA (United States)

    2007-08-01

    Since the 1980's, the study of nucleon (proton or neutron) spin structure has been an active field both experimentally and theoretically. One of the primary goals of this work is to test our understanding of Quantum Chromodynamics (QCD), the fundamental theory of the strong interaction. In the high energy region of asymptotically free quarks, QCD has been verified. However, verifiable predictions in the low energy region are harder to obtain due to the complex interactions between the nucleon's constituents: quarks and gluons. In the non-pertubative regime, low-energy effective field theories such as chiral perturbation theory provide predictions for the spin structure functions in the form of sum rules. Spin-dependent sum rules such as the Gerasimov-Drell-Hearn (GDH) sum rule are important tools available to study nucleon spin structure. Originally derived for real photon absorption, the Gerasimov-Drell-Hearn (GDH) sum rule was first extended for virtual photon absorption in 1989. The extension of the sum rule provides a unique relation, valid at any momentum transfer ($Q^{2}$), that can be used to study the nucleon spin structure and make comparisons between theoretical predictions and experimental data. Experiment E97-110 was performed at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) to examine the spin structure of the neutron and $^{3}$He. The Jefferson Lab longitudinally-polarized electron beam with incident energies between 1.1 and 4.4 GeV was scattered from a longitudinally or transversely polarized $^{3}$He gas target in the Hall A end station. Asymmetries and polarized cross-section differences were measured in the quasielastic and resonance regions to extract the spin structure functions $g_{1}(x,Q^{2})$ and $g_{2}(x,Q^{2})$ at low momentum transfers (0.02 $< Q^{2} <$ 0.3 GeV$^{2}$). The goal of the experiment was to perform a precise measurement of the $Q^{2}$ dependence of the extended GDH integral and of the moments of

  20. The Accelerating Spin Of 9P/Tempel 1

    Science.gov (United States)

    Belton, Michael J.; Drahus, M.

    2007-10-01

    Deep Impact approach photometry has been analyzed using the dynamical techniques introduced by Drahus and Waniak (2006). Clear indications of acceleration (0.70 +/- 0.24 x 10-7 h-2) in the spin rate are found together with a spin period of 40.850 +/- 0.017 h at the mid point of the data set (June 2.38304, 2005 UT). This measurement of acceleration in the spin is similar to that deduced independently from a combination of spin rate measurements derived from the Deep Impact Earth-based campaign (Meech et al. 2005), Spitzer observations (Lisse et al. 2005), and Deep Impact approach data (A'Hearn et al. 2005). Estimates of the spin rate from these sources (Belton et al. 2007) at epochs between 1999 and 2006 were coupled through the 2005 perihelion passage using a heuristic spin rate change model based on non-gravitational torques due to the outflow of H2O. This model yields a preliminary estimate of 1.15×10-7 h-2 for the acceleration of the spin at the mid point of the data set; it also suggests that the net torque is dominated by activity in the Northern hemisphere of the nucleus. Although non-constant periodicities have been reported for a few comets before, the evidence has never been detected as clearly and unambiguously as for 9P/Tempel 1. This discovery strongly impacts the preparations for the Stardust-NExT mission (http://stardust.jpl.nasa.gov/news/status/070703.html) scheduled to arrive at the comet in 2011. References: A'Hearn, M.F. and 32 colleagues, 2005. Science 310, 258-264. Belton, M.J.S. and 35 colleagues, 2007. In preparation. Drahus, M, and Waniak, W. 2006, Icarus 185, 544 Lisse, C.M and 8 colleagues 2005. Astrophys. J. 625, L139-L142. Meech, K.J. and 208 colleagues, 2005. Science 310, 265-269.

  1. First doubly polarised photoproduction on 3He at the photon beam of MAMI

    International Nuclear Information System (INIS)

    Aguar Bartolome, Patricia

    2010-11-01

    A first experiment with a polarised 3 He target was carried out in July 2009 at the MAMI accelerator in Mainz in a photon energy range between 200 MeV and 800 MeV. The aim of this measurement was to investigate the Gerasimov-Drell-Hearn sum rule on the neutron. The use of the data obtained with the polarised 3 He target, compared to existing data on the deuteron, gives a complementary and more direct access to the neutron, due to the spin structure of the 3 He. The measurement of the helicity dependence of the inclusive total photoabsorption cross section required a beam of tagged circularly polarised photons incident on the longitudinally polarised 3 He target. The data were taken using the 4π Crystal Ball photon spectrometer in combination with TAPS as a forward wall and complemented by a threshold Cherenkov detector used to on-line suppress the background from electromagnetic events. The development and preparation of the different components of the 3 He experimental setup was an important part of this work and are described in detail in this thesis. The detector system and the analysis method were tested by the measurement of the unpolarised total inclusive photoabsorption cross section on liquid hydrogen. The results obtained are in good agreement with previous published data. Preliminary results of the unpolarised total photoabsorption cross section, as well as the helicity dependent photoabsorption cross section difference on 3 He compared with several theoretical models will also be presented. (orig.)

  2. Moments of the Spin Structure Functions g1p and g1d for 0.05 < Q2 < 3.0 GeV2

    Energy Technology Data Exchange (ETDEWEB)

    Prok, Yelena; Bosted, Peter; Burkert, Volker; Deur, Alexandre; Dharmawardane, Kahanawita; Dodge, Gail; Griffioen, Keith; Kuhn, Sebastian; Minehart, Ralph; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Anghinolfi, Marco; Asryan, G.; Audit, Gerard; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Beard, Kevin; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Boyarinov, Sergey; Bonner, Billy; Bouchigny, Sylvain; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Casey, Liam; Cazes, Antoine; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Cords, Dieter; Corvisiero, Pietro; Crabb, Donald; Crede, Volker; Cummings, John; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Dhuga, Kalvir; Dickson, Richard; Djalali, Chaden; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Feldman, Gerald; Fersch, Robert; Feuerbach, Robert; Forest, Tony; Fradi, Ahmed; Funsten, Herbert; Garcon, Michel; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Golovach, Evgeny; Gothe, Ralf; Guidal, Michel; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hardie, John; Hassall, Neil; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Huertas, Marco; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keith, Christopher; Kellie, James; Khandaker, Mahbubul; Kim, Kui; Kim, Kyungmo; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klusman, Mike; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, Dave; Lima, Ana; Livingston, Kenneth; Lu, Haiyun; Lukashin, K.; MacCormick, Marion; Marchand, Claude; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Morand, Ludyvine; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; O' Rielly, Grant; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Anefalos Pereira, S.; Philips, Sasha; Pierce, J.; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Popa, Iulian; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Procureur, Sebastien; Protopopescu, Dan; Qin, Liming; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Rowntree, David; Rubin, Philip; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schumacher, Reinhard; Seely, Mikell; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shaw, Jeffrey; Shvedunov, Nikolay; Skabelin, Alexander; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinskiy, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Suleiman, Riad; Taiuti, Mauro; Tedeschi, David; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Todor, Luminita; Ungaro, Maurizio; V

    2009-02-01

    The spin structure functions $g_1$ for the proton and the deuteron have been measured over a wide kinematic range in $x$ and \\Q2 using 1.6 and 5.7 GeV longitudinally polarized electrons incident upon polarized NH$_3$ and ND$_3$ 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 \\Q2, as predicted by the extended Gerasimov-Drell-Hearn sum rule. The first result for the generalized forward spin polarizability of the proton $\\gamma_0^p$ is also reported, and shows evidence of scaling above $Q^2$ = 1.5 GeV$^2$. Although the first moments of $g_1$ are consistent with Chiral Perturbation Theory (\\ChPT) calculations up to approximately $Q^2 = 0.06$ GeV$^2$, a significant discrepancy is observed between the $\\gamma_0^p$ data and \\ChPT\\ for $\\gamma_0^p$,even at the lowest \\Q2.

  3. Updated ozone absorption cross section will reduce air quality compliance

    Directory of Open Access Journals (Sweden)

    E. D. Sofen

    2015-12-01

    et al. (2015 as 1.8 % smaller than the accepted value (Hearn, 1961 used for the preceding 50 years. Thus, ozone measurements that applied the older cross section systematically underestimate the amount of ozone in air. We correct the reported historical surface data from North America and Europe and find that this modest change in cross section has a significant impact on the number of locations that are out of compliance with air quality regulations if the air quality standards remain the same. We find 18, 23, and 20 % increases in the number of sites that are out of compliance with current US, Canadian, and European ozone air quality health standards for the year 2012. Should the new cross-section value be applied, it would impact attainment of air quality standards and compliance with relevant clean air acts, unless the air quality target values themselves were also changed proportionately. We draw attention to how a small change in gas metrology has a global impact on attainment and compliance with legal air quality standards. We suggest that further laboratory work to evaluate the new cross section is needed and suggest three possible technical and policy responses should the new cross section be adopted.

  4. Influence of the surface drag coefficient (young waves) on the current structure of the Berre lagoon

    Science.gov (United States)

    Alekseenko, Elena; Roux, Bernard; Kharif, Christian; Sukhinov, Alexander; Kotarba, Richard; Fougere, Dominique; Chen, Paul Gang

    2013-04-01

    Due to the shallowness, currents and hydrodynamics of Berre lagoon (South of France) are closely conditioned by the bottom topography, and wind affects the entire water column, as for many other Mediterranean lagoons (Perez-Ruzafa, 2011). Wind stress, which is caused by moving atmospheric disturbance, is known to have a major influence in lagoon water circulation. According to the numerical simulation for the main directions of the wind: N-NW, S-SE and W (wind speed of 80 km/h) it is observed that the current is maximal alongshore in the wind direction; the bottom nearshore current being larger in shallower area. This fact is coherent with fundamental principle of wind-driven flows in closed or partially closed basins which states that in shallow water the dominant force balance is between surface wind stress and bottom friction, yielding a current in the direction of the wind (Mathieu et al, 2002, Hunter and Hearn, 1987; Hearn and Hunter,1990). A uniform wind stress applied at the surface of a basin of variable depth sets up a circulation pattern characterized by relatively strong barotropic coastal currents in the direction of the wind, with return flow occurring over the deeper regions (Csanady, 1967; Csanady, 1971). One of the key parameters characterizing the wind stress formulation is a surface drag coefficient (Cds). Thus, an effect of a surface drag coefficient, in the range 0.0016 - 0.0032, will be analyzed in this work. The value of surface drag coefficient Cds = 0.0016 used in our previous studies (Alekseenko et al., 2012), would correspond to mature waves (open sea). But, in the case of semi-closed lagoonal ecosystem, it would be more appropriate to consider "young waves" mechanism. A dependency of this coefficient in terms of the wind speed is given by Young (1999) in both cases of mature waves and young waves. For "young waves" generated at a wind speed of 80 km/h, Cds = 0.0032. So, the influence of Cds on the vertical profile of the velocity in the

  5. Moments of the spin structure functions g1p and g1d for 0.0522

    International Nuclear Information System (INIS)

    Prok, Y.; Bosted, P.; Burkert, V.D.; Deur, A.; Dharmawardane, K.V.; Dodge, G.E.; Griffioen, K.A.; Kuhn, S.E.; Minehart, R.; Adams, G.; Amaryan, M.J.; Anghinolfi, M.; Asryan, G.; Audit, G.; Avakian, H.; Bagdasaryan, H.; Baillie, N.; Ball, J.P.; Baltzell, N.A.; Barrow, S.

    2009-01-01

    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 NH 3 and ND 3 targets at Jefferson Lab. Scattered electrons were detected in the CEBAF Large Acceptance Spectrometer, for 0.05 2 2 and W 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

  6. Combination of BTrackS and Geri-Fit as a targeted approach for assessing and reducing the postural sway of older adults with high fall risk

    Directory of Open Access Journals (Sweden)

    Goble DJ

    2017-02-01

    Full Text Available Daniel J Goble, Mason C Hearn, Harsimran S Baweja School of Exercise and Nutritional Sciences, College of Health and Human Services, San Diego State University, San Diego, CA, USA Abstract: Atypically high postural sway measured by a force plate is a known risk factor for falls in older adults. Further, it has been shown that small, but significant, reductions in postural sway are possible with various balance exercise interventions. In the present study, a new low-cost force-plate technology called the Balance Tracking System (BTrackS was utilized to assess postural sway of older adults before and after 90 days of a well-established exercise program called Geri-Fit. Results showed an overall reduction in postural sway across all participants from pre- to post-intervention. However, the magnitude of effects was significantly influenced by the amount of postural sway demonstrated by individuals prior to Geri-Fit training. Specifically, more participants with atypically high postural sway pre-intervention experienced an overall postural sway reduction. These reductions experienced were typically greater than the minimum detectable change statistic for the BTrackS Balance Test. Taken together, these findings suggest that BTrackS is an effective means of identifying older adults with elevated postural sway, who are likely to benefit from Geri-Fit training to mitigate fall risk. Keywords: aging, balance, BTrackS, Geri-Fit, postural sway, fall risk

  7. Portland Energy Centre: Securing supply and clearing the air

    International Nuclear Information System (INIS)

    2003-02-01

    The rationale for, and benefits derivable from the proposed Portland natural gas-fired cogeneration plant, to be located beside the former Hearn power station near the Leslie Street Spit in Toronto, are discussed. The justification for and the single most important benefit promised by the proposed plant is that it could help Ontario achieve its coal phase-out target by displacing 100 per cent of the annual output of the Lakeview coal--fired power plant in Mississauga, as well as six per cent of the annual output of the Nanticoke coal-fired power plant, in total supplying about 10 per cent of Toronto's electricity needs and providing steam to heat several office towers in downtown Toronto. Other benefits discussed include substantially improved air quality, reduced incidence of asthma and heart attacks, a more reliable power supply for Toronto, some 500 new jobs during construction, and 25 to 35 permanent jobs to operate the plant. The Fact Sheet also offers suggestions on how to generate political support for this project in particular and for renewable power sources in general

  8. Electroweak processes in few-nucleon systems

    International Nuclear Information System (INIS)

    Arenhoevel, H.

    1999-01-01

    After a brief introduction into the basic ingredients of electroweak theory as a spontaneously broken local, non-Abelian gauge symmetry, the general properties of the electromagnetic current and two-photon operators are discussed. In particular, the consequences of gauge invariance and the resulting low-energy theorems are reviewed. The multipole decomposition of the current operators and the general Siegert theorem are presented. The specific forms of vector and axial one-nucleon currents are given, together with lowest-order π-meson exchange and isobar currents as well as meson production currents. A brief overview is given on the most important one- and two-boson processes. Electron scattering in the one-boson approximation is then considered in greater detail. Formal expressions of the cross section for inclusive and exclusive processes are given, including parity-violating contributions from γ-Z interference as well as from parity-violating components in the hadronic wave function. Specific electromagnetic reactions on the deuteron are then discussed with respect to the influence of meson exchange currents, isobar configurations in the deuteron ground state, relativistic contributions and the role of π-meson retardation. Furthermore, recent results on coherent and incoherent π and η-photoproduction are presented as well as a discussion of the Gerasimov-Drell-Hearn sum rule and the effect of a parity-violating deuteron component on inclusive electron scattering off the deuteron for quasifree kinematics. The review closes with a summary and a brief outlook. (author)

  9. First doubly polarised photoproduction on {sup 3}He at the photon beam of MAMI

    Energy Technology Data Exchange (ETDEWEB)

    Aguar Bartolome, Patricia

    2010-11-15

    A first experiment with a polarised {sup 3}He target was carried out in July 2009 at the MAMI accelerator in Mainz in a photon energy range between 200 MeV and 800 MeV. The aim of this measurement was to investigate the Gerasimov-Drell-Hearn sum rule on the neutron. The use of the data obtained with the polarised {sup 3}He target, compared to existing data on the deuteron, gives a complementary and more direct access to the neutron, due to the spin structure of the {sup 3}He. The measurement of the helicity dependence of the inclusive total photoabsorption cross section required a beam of tagged circularly polarised photons incident on the longitudinally polarised {sup 3}He target. The data were taken using the 4{pi} Crystal Ball photon spectrometer in combination with TAPS as a forward wall and complemented by a threshold Cherenkov detector used to on-line suppress the background from electromagnetic events. The development and preparation of the different components of the {sup 3}He experimental setup was an important part of this work and are described in detail in this thesis. The detector system and the analysis method were tested by the measurement of the unpolarised total inclusive photoabsorption cross section on liquid hydrogen. The results obtained are in good agreement with previous published data. Preliminary results of the unpolarised total photoabsorption cross section, as well as the helicity dependent photoabsorption cross section difference on {sup 3}He compared with several theoretical models will also be presented. (orig.)

  10. Magnetohydrodynamics: Parallel computation of the dynamics of thermonuclear and astrophysical plasmas. 1. Annual report of massively parallel computing pilot project 93MPR05

    International Nuclear Information System (INIS)

    1994-08-01

    This is the first annual report of the MPP pilot project 93MPR05. In this pilot project four research groups with different, complementary backgrounds collaborate with the aim to develop new algorithms and codes to simulate the magnetohydrodynamics of thermonuclear and astrophysical plasmas on massively parallel machines. The expected speed-up is required to simulate the dynamics of the hot plasmas of interest which are characterized by very large magnetic Reynolds numbers and, hence, require high spatial and temporal resolutions (for details see section 1). The four research groups that collaborated to produce the results reported here are: The MHD group of Prof. Dr. J.P. Goedbloed at the FOM-Institute for Plasma Physics 'Rijnhuizen' in Nieuwegein, the group of Prof. Dr. H. van der Vorst at the Mathematics Institute of Utrecht University, the group of Prof. Dr. A.G. Hearn at the Astronomical Institute of Utrecht University, and the group of Dr. Ir. H.J.J. te Riele at the CWI in Amsterdam. The full project team met frequently during this first project year to discuss progress reports, current problems, etc. (see section 2). The main results of the first project year are: - Proof of the scalability of typical linear and nonlinear MHD codes - development and testing of a parallel version of the Arnoldi algorithm - development and testing of alternative methods for solving large non-Hermitian eigenvalue problems - porting of the 3D nonlinear semi-implicit time evolution code HERA to an MPP system. The steps that were scheduled to reach these intended results are given in section 3. (orig./WL)

  11. Nuclear physics with laser-electron-photons. Developments and perspectives at SPring-8

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, Mamoru [Osaka Univ., Ibaraki (Japan). Research Center for Nuclear Physics

    1998-03-01

    By the Compton scattering with ultraviolet laser beam using the 8 GeV electron beam of the SPring-8, the photon beam which is polarized by nearly 100% is obtained in 1-3.5 GeV region. The quark nuclear physics research at this facility is unique in the world, and it is expected that in the experiment at the SPring-8, the collision phenomena of polarized, high energy gamma-ray and the quarks in nucleons and the knockout phenomena of quarks are observed. Also the polarization experiment for clarifying ``the origin of nucleon spin`` has been proposed. Japan can stand at the top in the world in the research of quark nuclear physics with leptons. In the inverse Compton scattering using far infrared laser, the gamma-ray with good directionality of MeV range is obtained, and it will be applied widely to the research on E1 resonance and M1 excitation of atomic nuclei. In this report, the medium energy quark nuclear physics developed at the SPring-8 is outlined, and the nuclear physics which is expected to be developed when the high intensity, high polarization gamma-ray of about 10 MeV is generated is discussed. The detection of s, anti-s components in nucleons, research on baryon deformation and baryon spectra, verification of the Gerasimov, Drell-Hearn law of sum, meson structure, test of quark model by the photolysis of deuterons, dual Ginzburg Landau theory exploration, research on the mass and behavior of mesons in nuclear media are discussed. (K.I.)

  12. Spitzer and Chandra Observations of the Deep Impact Encounter with Comet 9P/Tempel 1

    Science.gov (United States)

    Lisse, C. M.; A'Hearn, M. F.; Belton, M. J. S.; Bodewits, D.; Christian, D. J.; VanCleve, J.; Combi, M.; Dennerl, K.; Farnham, T. L.; Fernandez, Y. R.; Groussin, O.; Hoekstra, R.; Makinen, T.; McFadden, L. A.; Meech, K. J.; Schultz, P.; Weaver, H.; Wolk, S.

    2005-12-01

    On July 4, 2005 NASA's discovery mission Deep Impact (hereafter DI) sent a 375 kg impactor into the nucleus of comet 9P/Tempel 1 at 10.2 km/s relative velocity (A'Hearn et al. 2005). In the IR, Spitzer observed the comet in the unique 5-38 μm spectral range provided by the IRS instrument, allowing direct determination of silicaceous dust, PAHs, carbonates, and aluminum and iron oxides/sulfides in the subsurface material. The Spitzer observations contrasted well with the 1-5 μm spectra obtained by the DI High Resolution Instrument's IR spectrometer and ground based measurements at 1-5 um from the Keck and IRTF observatories (Meech et al. 2005), enabling us to obtain full coverage of the comet's IR spectrum from 1.0 to 38 μm. In the x-ray, the DI experiment allowed for a controlled test of the charge exchange (CXE) emission mechanism that drives cometary x-ray emission (Lisse et al. 2001, Kharchenko and Dalgarno 2001, Krasnopolsky et al. 2002) using observations with the Chandra ACIS-S CCD. The Chandra spectra show a fresh amount of neutral material was injected into a finite volume of the extended atmosphere, or coma, of the comet. In the matter of minutes, this new material directly increased the emission measure for the comet by 30 production from other measurements. Additional contemporaneous measurements by the XMM and SWIFT low energy x-ray imagers provided complimentary lightcurve data points, providing a good long term estimate of the comet's gas emission before, during, and after the Deep Impact encounter. Over the longer term, the combined lightcurves showed evidence of multiple natural outbursts of neutral gas emission from the comet.

  13. Study of the coma of comet 67P/Churyumov-Gerasimenko based on the ROSINA/RTOF instrument onboard Rosetta

    Science.gov (United States)

    Hoang, M.; Garnier, P.; Lasue, J.; Reme, H.; Altwegg, K.; Balsiger, H. R.; Bieler, A. M.; Calmonte, U.; Fiethe, B.; Galli, A.; Gasc, S.; Gombosi, T. I.; Jäckel, A.; Mall, U.; Le Roy, L.; Rubin, M.; Tzou, C. Y.; Waite, J. H., Jr.; Wurz, P.

    2015-12-01

    The ROSETTA spacecraft of ESA is in the environment of comet 67P/Churyumov-Gerasimenko since August 2014. Among the experiments onboard the spacecraft, the ROSINA experiment (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) includes two mass spectrometers (DFMS and RTOF) to analyze the composition of neutrals and ions, and a pressure sensor (COPS) to monitor the density and velocity of neutrals in the coma [1]. We will here analyze and discuss the data of the ROSINA/RTOF instrument during the comet escort phase. The Reflectron-type Time-Of-Flight (RTOF) mass spectrometer possesses a wide mass range and a high temporal resolution [1,2]. It was designed to measure cometary neutral gas as well as cometary ions. A detailed description of the main volatiles (H2O, CO2, CO) dynamics and of the heterogeneities of the coma will then be provided. The influence of various parameters on the coma measurements is investigated on a statistical basis, with the parameters being distance to the comet, heliocentric distance, longitude and latitude of nadir point. Our analysis of the northern hemisphere summer season shows the presence of water vapor mostly in the illuminated northern hemisphere near the neck region with cyclic diurnal variations whereas CO2 was confined to the cold southern hemisphere with a more spatially homogeneous composition, in agreement with previous observations of 67P [2] or Hartley 2 [3]. A comparison will also be provided with the COPS total density and DFMS abundance measurements. [1] Balsiger et al., "ROSINA - Rosetta Orbiter Spectrometer for Ion and Neutral Analysis", Space Sci. Rev., 2007. [2] Scherer et al., "A novel principle for an ion mirror design in time-of-flight mass spectrometry," Int. Jou. Mass Spectr., 2006. [3] Hässig et al., "Time variability and heterogeneity in the coma of 67P/Churyumov-Gerasimenko", Science, 2015. [4] A'Hearn et al., "EPOXI at comet Hartley 2", Science, 2011.

  14. Manipulating the reported age in earliest memories.

    Science.gov (United States)

    Wessel, Ineke; Schweig, Theresa; Huntjens, Rafaële J C

    2017-11-02

    Previous work suggests that the estimated age in adults' earliest autobiographical memories depends on age information implied by the experimental context [e.g., Kingo, O. S., Bohn, A., & Krøjgaard, P. (2013). Warm-up questions on early childhood memories affect the reported age of earliest memories in late adolescence. Memory, 21(2), 280-284. doi: 10.1080/09658211.2012.729598 ] and that the age in decontextualised snippets of memory is younger than in more complete accounts (i.e., event memories [Bruce, D., Wilcox-O'Hearn, L. A., Robinson, J. A., Phillips-Grant, K., Francis, L., & Smith, M. C. (2005). Fragment memories mark the end of childhood amnesia. Memory & Cognition, 33(4), 567-576. doi: 10.3758/BF03195324 ]). We examined the malleability of the estimated age in undergraduates' earliest memories and its relation with memory quality. In Study 1 (n = 141), vignettes referring to events happening at age 2 rendered earlier reported ages than examples referring to age 6. Exploratory analyses suggested that event memories were more sensitive to the age manipulation than memories representing a single, isolated scene (i.e., snapshots). In Study 2 (n = 162), asking self-relevant and public-event knowledge questions about participants' preschool years prior to retrieval yielded comparable average estimated ages. Both types of semantic knowledge questions rendered earlier memories than a no-age control task. Overall, the reported age in snapshots was younger than in event memories. However, age-differences between memory types across conditions were not statistically significant. Together, the results add to the growing literature indicating that the average age in earliest memories is not as fixed as previously thought.

  15. Teleseismic P and S Delay Times within Tectonically Active and Stable North America

    Science.gov (United States)

    Lou, X.; van der Lee, S.

    2009-12-01

    We have measured teleseismic P and S relative delay times within 1) Stable North America (SNA) using waveforms from IRIS PASSCAL seismic arrays MOMA (Fischer et al., 1995), ABBA (Roecker and Beavan, 1995), Abitibi (Hearn and Mareschal, 1996), and FLED (Wysession and Fischer, 2001), and 2) Tectonically-active North America (TNA) using Earthscope's Transportable Array (TA). To study the contribution of mantle structure to these delays we subtracted delays predicted for topography and crustal structure, using CRUST 2.0 (Bassin et al., 2000). Preliminary analyses of delay times from earthquakes with Mw>=6.5 show surprising differences between the heterogeneity of the mantle beneath SNA and TNA. While the range of delay times is expectedly small for an intra-shield array such as Abitibi, the range of delay times from Proterozoic basement in the midwest to Paleozoic margin in New England is much larger and slightly exceeds that for the TA in TNA. This suggests that that the mantle of SNA is slightly more heterogeneous than TNA, despite there being relatively little surface expression of this heterogeneity. Patterns of P and S relative delay times measured in TNA correlate better with surface tectonics, suggesting that the mantle in TNA has a greater effect on the surface geology than in SNA. The central and southern Basin and Range are characterized by positive delays. As shown in previous studies, the Snake River Plain is also well delineated by positive delays. These delays exhibit a significant peak at station H17A in Yellowstone National Park. Teleseismic P and S waves arriving at stations in the Rocky Mountains are much faster, including in northern Idaho and western Washington, but not in western Oregon. For both SNA and TNA, the measured S and P delay times have a significant linear correlation, with S delays at approximately 3 times the P delays, which confirms the dominant effect of mantle temperature on mantle velocity structure. However, the slope of this

  16. Rosetta/OSIRIS: Nucleus morphology and activity of comet 67P/Churyumov-Gerasimenko

    Science.gov (United States)

    Sierks, Holger

    2015-08-01

    Introduction: The Rosetta mission of the European Space Agency arrived on August 6, 2014, at the target comet 67P/Churyumov-Gerasimenko after 10 years of cruise. OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) is the scientific imaging system onboard Rosetta. It comprises a Narrow Angle Camera (NAC) for broad-band nucleus surface and dust studies and a Wide Angle Camera (WAC) for the wide field coma investigations.OSIRIS images the nucleus and the coma of comet 67P/C-G from the arrival throughout early mapping phase, PHILAE landing, and escort phase with close fly-by beginning of the year 2015.The team paper presents the surface morphology and activity of the nucleus as seen in gas, dust, and local jets and the larger scale coma studied by OSIRIS.Acknowledgements: OSIRIS was built by a consortium led by the Max-Planck-Institut für Sonnensystemforschung, Göttingen, Germany, in collaboration with CISAS, University of Padova, Italy, the Laboratoire d'Astrophysique de Marseille, France, the Instituto de Astrofísica de Andalucia, CSIC, Granada, Spain, the Scientific Support Office of the European Space Agency, Noordwijk, The Netherlands, the Instituto Nacional de Técnica Aeroespacial, Madrid, Spain, the Universidad Politéchnica de Madrid, Spain, the Department of Physics and Astronomy of Uppsala University, Sweden, and the Institut für Datentechnik und Kommunikationsnetze der Technischen Universität Braunschweig, Germany.Additional Information: The OSIRIS team is H. Sierks, C. Barbieri, P. Lamy, R. Rodrigo, D. Koschny, H. Rickman, J. Agarwal, M. A'Hearn, I. Bertini, F. Angrilli, M. A. Barucci, J. L. Bertaux, G. Cremonese, V. Da Deppo, B. Davidsson, S. Debei, M. De Cecco, S. Fornasier, M. Fulle, O. Groussin, C. Güttler, P. Gutierrez, S. Hviid, W. Ip, L. Jorda, H. U. Keller, J. Knollenberg, R. Kramm, E. Kührt, M. Küppers, L. Lara, M. Lazzarin, J. J. Lopez, S. Lowry, S. Marchi, F. Marzari, H. Michalik, S. Mottola, G. Naletto, N. Oklay, L

  17. THE LONG-TERM DECAY IN PRODUCTION RATES FOLLOWING THE EXTREME OUTBURST OF COMET 17P/HOLMES

    International Nuclear Information System (INIS)

    Schleicher, David G.

    2009-01-01

    Numerous sets of narrowband filter photometry were obtained of Comet 17P/Holmes from Lowell Observatory during the interval of 2007 November 1 to 2008 March 5. Observations began 8 days following its extreme outburst, at which time the derived water production rate, based on OH measurements, was 5 x 10 29 molecule s -1 and the derived proxy of dust production, A(θ)fρ, was about 5 x 10 5 cm. Relative production rates for the other gas species, CN, C 2 , C 3 , and NH, are consistent with 'typical' composition (based on our update to the classifications by A'Hearn et al.). An exponential decay in the logarithm of measured production rates as a function of time was observed for all species, with each species dropping by factors of about 200-500 after 125 days. All gas species exhibited clear trends with aperture size, and these trends are consistent with larger apertures having a greater proportion of older material that was released when production rates were higher. Much larger aperture trends were measured for the dust, most likely because the dust grains have smaller outflow velocities and longer lifetimes than the gas species; therefore, a greater proportion of older, i.e., higher production dust is contained within a given aperture. By extrapolating to a sufficiently small aperture size, we derive near-instantaneous water and dust production rates throughout the interval of observation, and also estimate values immediately following the outburst. The finite lifetime of the gas species requires that much higher ice vaporization rates were taking place throughout the observation interval than occurred prior to the outburst, likely due to the continued release of icy grains from the nucleus. The relatively small aperture trends for the gas species also imply that the bulk of fresh, excess volatiles are confined to the nucleus and near-nucleus regime, rather than being associated with the outburst ejecta cloud. A minimum of about 0.1% of the total nucleus volume

  18. The significance of the Medicine Hat Block (southern Alberta, northern Montana) in the assembly of Laurentia: New interpretations from recent single grain zircon geochronological and geochemical data

    Science.gov (United States)

    LaDouceur, B. O.; Gifford, J.; Malone, S.; Davis, B.

    2017-12-01

    Keywords: Medicine Hat Block, Zircon, U/Pb ages, Hf isotopes, Laurentia The Medicine Hat Block (MHB) is one of the core cratonic elements that amalgamated in the Paleoproterozoic to form Laurentia. However, unlike many of the other cratons, the role of the MHB in the formation of Laurentia is poorly constrained. Virtually all of the MHB is concealed by Proterozoic and younger supracrustal sequences, limiting the data collected from this craton. The primary source of samples from the MHB comes from two sources: 1) xenoliths of variably metamorphoses gneisses, amphibolites, and meta-plutonic rocks collected from Eocene volcanic rock, and 2) similar lithologies recovered from boreholes that penetrate to the MHB basement. Multigrain zircon TIMS analyses yielded U/Pb ages ranging from 1.70 Ga to 3.26 Ga. Recent zircon single-grain LA-ICPMS U-Pb ages revealed a slightly older range of Archean ages, 2.63 Ga to 3.27 Ga, and two samples yielding Paleoproterozoic ages at 1.78 and 1.82 Ga. Whole-rock Sm/Nd data indicated that the samples formed from crustal sources, with model ages ranging between 1.80 Ga to 3.48 Ga. In-situ zircon Hf isotopic results revealed that Archean-aged zircon are generally suprachondritic, with eHf(t) values between 8.3 and -8.7. In contrast, the Paleoproterozoic grains yielded negative eHf(t) values ranging from -6.8 to -21.2, suggestive of a reworked Archean crustal component in their genesis. In particular, the Sweetgrass Hill xenolith suite is characterized solely by Paleoproterozoic ages, with evolved eHf(t) suggesting that any older U-Pb ages were reset by granulite facies metamorphism and zircon recrystallization. The combined U-Pb and Hf isotopic data from these samples helps illuminate the character of the MHB and its relationships to the Wyoming and Hearne cratons, as well as the Great Falls Tectonic Zone (GFTZ). The ages overlap between cratonic elements; however, the abundance of positive eHf(t) values of the 2.8 Ga ages suggests that the

  19. Highly Depleted Ethane and Slightly Depleted Methanol in Comet 21P/Giacobini-Zinner: Application of Empirical g-factors for CH3OH near 50 K

    Science.gov (United States)

    DiSanti, Michael A.; Bonev, B. P.; Villanueva, G. L.; Mumma, M. J.

    2012-10-01

    We report results from high resolution (λ/Δλ 24,000) infrared spectra of Comet 21P/Giacobini-Zinner (21P/GZ) using NIRSPEC at Keck II on UT 2005 June 03, approximately one month before perihelion. We simultaneously sampled emissions from the ν7 band of C2H6, the ν2 and ν3 bands of CH3OH, and several hot bands of H2O, permitting a direct measure of parent volatile abundances in 21P/GZ. Our production rate for H2O was consistent with that measured from previous apparitions as retrieved from optical, infrared, and mm-wavelength observations. Our analysis of C2H6 confirmed its previously reported strong depletion from IR observations during the 1998 apparition [1,2], similar to the depletion of C2 in 21P/GZ known from optical studies [3]. For CH3OH, we applied our recently published quantum model for ν3 [4], obtaining Trot consistent with that for H2O ( 50 K) and a high abundance ratio CH3OH/C2H6 ( 9). We observed similar Trot and CH3OH/C2H6 in Comet 8P/Tuttle [5,6], and used these to produce effective (empirical) ν2 g-factors for 157 lines [7]. Application of our empirical ν2 model to 21P/GZ provided a production rate consistent with that from ν3, and an abundance ratio CH3OH/H2O in agreement with that measured previously [1,8]. We present a summary of our results for 21P/GZ and compare with abundances obtained for other Jupiter family comets. Our study provides the first measure of primary volatile production rates for any JFC over multiple apparitions using high resolution ground-based IR spectroscopy. We acknowledge support from the NASA Planetary Atmospheres, Planetary Astronomy, and Astrobiology Programs and from the NSF Astronomy and Astrophysics Research Grants Program. References [1] Weaver et al. 1999 Icarus 142:482 [2] Mumma et al. 2000 ApJ 531:L155 [3] A’Hearn et al. 1995 Icarus 118:223 [4] Villanueva et al. 2012 ApJ 747:37 [5] Bonev et al. 2008 ApJ 680:L61 [6] Boehnhardt et al. 2008 ApJ 683:L71 [7] DiSanti et al. 2012 ApJ (in press) [8] Biver

  20. Unveiling the formation and evolution of comets

    Science.gov (United States)

    Lasue, J.; Levasseur-Regourd, A. C.; Botet, R.; Coradini, A.; Desanctis, M. C.; Kofman, W.

    2007-08-01

    energy of the cometesimals and their probable re-accretion after collision events in the Kuiper Belt can be used to interpret the typical layered structure observed for comet 9P/Tempel 1 [10] and evaluate the tensile strengths inside the nucleus. Thermal evolution models of comet nuclei explain the current comet observations with the presence of primordial volatiles [11]. A quasi-3D approach (for non-spherically shaped comet nuclei) is used to interpret the current activity of comets in terms of initial characteristics, and to predict shape and internal stratification evolution of the nucleus. Tensile strength indications and activity predictions from such simulations will provide vital clues for the international Rosetta mission landing on the nucleus of comet 67P/Churyumov-Gerasimenko. During the Rosetta rendezvous, the CONSERT experiment will investigate the deep interior of the nucleus from measurements of the propagation delay of long wavelength radio waves [12]. The analysis and 3D reconstruction of the waves passing through the nucleus will put constraints on the materials constituting the comet and the inhomogeneities within the nucleus. While it is now established that nuclei have low densities and are significantly fragile, it will then be possible to better constrain their formation process and their evolution. [1] A'Hearn et al., Science 310, 258 (2005) [2] Samarasinha, Icarus 154, 540 (2001) [3] Trigo-Rodriguez and Llorca, Mon. Not. R. Astron. Soc. 372, 655 (2006) [4] A'Hearn and Combi, Icarus 187, 1 (2007) [5] Hanner and Bradley, In: Comets II, Festou, Keller, Weaver (eds), pp 555 (2004) [6] Brownlee et al., Science 314, 1711 (2006) [7] Lasue and Levasseur-Regourd, J. Quant. Spectros. Radiat. Transfer 100, 220-236 (2006) [8]Levasseur-Regourd et al., (2007), Planet Space Sci., doi:10.1016/j.pss.2006.11.014 in press. [9] Hörz et al., Science 314, 1716 (2006) [10] Belton et al., Icarus 187, 332 (2007) [11] DeSanctis et al., Astron. Astrophys. 444, 605 (2005

  1. Comet Dust After Deep Impact

    Science.gov (United States)

    Wooden, Diane H.; Harker, David E.; Woodward, Charles E.

    2006-01-01

    When the Deep Impact Mission hit Jupiter Family comet 9P/Tempel 1, an ejecta crater was formed and an pocket of volatile gases and ices from 10-30 m below the surface was exposed (A Hearn et aI. 2005). This resulted in a gas geyser that persisted for a few hours (Sugita et al, 2005). The gas geyser pushed dust grains into the coma (Sugita et a1. 2005), as well as ice grains (Schulz et al. 2006). The smaller of the dust grains were submicron in radii (0-25.3 micron), and were primarily composed of highly refractory minerals including amorphous (non-graphitic) carbon, and silicate minerals including amorphous (disordered) olivine (Fe,Mg)2SiO4 and pyroxene (Fe,Mg)SiO3 and crystalline Mg-rich olivine. The smaller grains moved faster, as expected from the size-dependent velocity law produced by gas-drag on grains. The mineralogy evolved with time: progressively larger grains persisted in the near nuclear region, having been imparted with slower velocities, and the mineralogies of these larger grains appeared simpler and without crystals. The smaller 0.2-0.3 micron grains reached the coma in about 1.5 hours (1 arc sec = 740 km), were more diverse in mineralogy than the larger grains and contained crystals, and appeared to travel through the coma together. No smaller grains appeared at larger coma distances later (with slower velocities), implying that if grain fragmentation occurred, it happened within the gas acceleration zone. These results of the high spatial resolution spectroscopy (GEMINI+Michelle: Harker et 4. 2005, 2006; Subaru+COMICS: Sugita et al. 2005) revealed that the grains released from the interior were different from the nominally active areas of this comet by their: (a) crystalline content, (b) smaller size, (c) more diverse mineralogy. The temporal changes in the spectra, recorded by GEMIM+Michelle every 7 minutes, indicated that the dust mineralogy is inhomogeneous and, unexpectedly, the portion of the size distribution dominated by smaller grains has

  2. Book reviews

    Directory of Open Access Journals (Sweden)

    Redactie KITLV

    2010-12-01

    úa, by Allen Wells (reviewed by Michael R. Hall Downtown Ladies: Informal Commercial Importers, a Haitian Anthropologist, and Self-Making in Jamaica, by Gina A. Ulysse (reviewed by Jean Besson Une ethnologue à Port-au-Prince: Question de couleur et luttes pour le classement socio-racial dans la capitale haïtienne, by Natacha Giafferi-Dombre (reviewed by Catherine Benoît Haitian Vodou: Spirit, Myth, and Reality, edited by Patrick Bellegarde-Smith & Claudine Michel (reviewed by Susan Kwosek Cuba: Religion, Social Capital, and Development, by Adrian H. Hearn (reviewed by Nadine Fernandez "Mek Some Noise": Gospel Music and the Ethics of Style in Trinidad, by Timothy Rommen (reviewed by Daniel A. Segal Routes and Roots: Navigating Caribbean and Pacific Island Literatures, by Elizabeth M. DeLoughrey (reviewed by Anthony Carrigan Claude McKay, Code Name Sasha: Queer Black Marxism and the Harlem Renaissance, by Gary Edward Holcomb (reviewed by Brent Hayes Edwards The Sense of Community in French Caribbean Fiction, by Celia Britton (reviewed by J. Michael Dash Imaging the Chinese in Cuban Literature and Culture, by Ignacio López-Calvo (reviewed by Stephen Wilkinson Pre-Columbian Jamaica, by P. Allsworth-Jones (reviewed by William F. Keegan Underwater and Maritime Archaeology in Latin America and the Caribbean, edited by Margaret E. Leshikar-Denton & Pilar Luna Erreguerena (reviewed by Erika Laanela

  3. THE COMPOSITION OF THE INTERIOR OF COMET 73P/SCHWASSMANN-WACHMANN 3: RESULTS FROM NARROWBAND PHOTOMETRY OF MULTIPLE COMPONENTS

    International Nuclear Information System (INIS)

    Schleicher, David G.; Bair, Allison N.

    2011-01-01

    probe the chemical composition of the relatively pristine interior. Relative abundances, expressed as production rate ratios between gas species, were compared among the four components and to values determined prior to the fragmentation, as well as to those measured in other comets. Our measurements indicate each component, to within the uncertainties, has the same composition and that this composition is consistent with that measured in the pre-fragmented nucleus. Moreover, C 2 and C 3 are both strongly depleted when compared to the majority of comets, placing Schwassmann-Wachmann 3 among the more extreme comets within the carbon-chain depleted class identified by A'Hearn et al. With the material released from the interior of the comet yielding comparable depletions of carbon-chain molecules as the original surface of the nucleus, we conclude that carbon-chain depletion is not caused by evolution of the surface, and so must instead reflect the primordial composition at the time and location that the comet accreted.

  4. Thermal model of water and CO activity of Comet C/1995 O1 (Hale-Bopp)

    Science.gov (United States)

    Gortsas, N.; Kührt, E.; Motschmann, U.; Keller, H. U.

    2011-04-01

    An investigation of the activity of Comet C/1995 O1 (Hale-Bopp) with a thermophysical nucleus model that does not rely on the existence of amorphous ice is presented. Our approach incorporates recent observations allowing to constrain important parameters that control cometary activity. The model accounts for heat conduction, heat advection, gas diffusion, sublimation, and condensation in a porous ice-dust matrix with moving boundaries. Erosion due to surface sublimation of water ice leads to a moving boundary. The movement of the boundary is modeled by applying a temperature remapping technique which allows us to account for the loss in the internal energy of the eroded surface material. These kind of problems are commonly referred to as Stefan problems. The model takes into account the diurnal rotation of the nucleus and seasonal effects due to the strong obliquity of Hale-Bopp as reported by Jorda et al. (Jorda, L., Rembor, K., Lecacheux, J., Colom, P., Colas, F., Frappa, E., Lara, L.M. [1997]. Earth Moon Planets 77, 167-180). Only bulk sublimation of water and CO ice are considered without further assumptions such as amorphous ices with certain amount of occluded CO gas. Confined and localized activity patterns are investigated following the reports of Lederer and Campins (Lederer, S.M., Campins, H. [2002]. Earth Moon Planets 90, 381-389) about the chemical heterogeneity of Hale-Bopp and of Bockelée-Morvan et al. (Bockelée-Morvan, D., Henry, F., Biver, N., Boissier, J., Colom, P., Crovisier, J., Despois, D., Moreno, R., Wink, J. [2009]. Astron. Astrophys. 505, 825-843) about a strong CO source at a latitude of 20°. The best fit to the observations of Biver et al. (Biver, N. et al. [2002]. Earth Moon Planets 90, 5-14) is obtained with a low thermal conductivity of 0.01 W m -1 K -1. This is in agreement with recent results of the Deep Impact mission to 9P/Tempel 1 (Groussin, O., A'Hearn, M.F., Li, J.-Y., Thomas, P.C., Sunshine, J.M., Lisse, C.M., Meech, K

  5. Comet radar explorer

    Science.gov (United States)

    Farnham, Tony; Asphaug, Erik; Barucci, Antonella; Belton, Mike; Bockelee-Morvan, Dominique; Brownlee, Donald; Capria, Maria Teresa; Carter, Lynn; Chesley, Steve; Farnham, Tony; Gaskell, Robert; Gim, Young; Heggy, Essam; Herique, Alain; Klaasen, Ken; Kofman, Wlodek; Kreslavsky, Misha; Lisse, Casey; Orosei, Roberto; Plaut, Jeff; Scheeres, Dan

    will enjoy significant simplifying benefits compared to using the same instrument for Mars or lunar radar science: (1) The proximity of operations leads to a much higher signal to noise, as much as +30 dB. (2) The lack of an ionosphere simplifies data modeling and analysis. (3) The body is globally illuminated during every data acquisition, minimizing ambiguity or 'clutter' and allowing for tomographic reconstruction. What is novel is the data processing, where instead of a planar radargram approach we coherently process the data into an image of the deep interior. CORE thus uses a MARSIS-SHARAD heritage radar to make coherent reflection sounding measurements, a 'CAT SCAN' of a comet nucleus. What is unique about this mission compared to the Mars radars mentioned above, is that the target is a finite mass of dirty ice in free space, rather than a sheet of dirty ice draped on a planet surface. The depth of penetration (kilometers), attainable resolution (decameters), and the target materials, are more or less the same. This means that the science story is robust, and the radar implementation is robust. The target is comet 10P/Tempel 2, discovered by Wilhelm Tempel in 1873 and observed on most apparitions since. It has been extensively studied, in part because of interest as a CRAF target in the mid-1980s, and much is known about it. Tempel 2 is one of the largest known comet nuclei, 16×8×8 km (about the same size as Halley) [1] and has rotation period 8.9 hours [3,5,6,7,9]. The spin state is evolving with time, spinning up by ˜10 sec per perihelion pass [5,7]. The comet is active, but not exceedingly so, especially given its size. The water production is measured at ˜ 4 × 1028 mol/sec at its peak [2], a factor of 25 lower than comet Halley, and it is active over only ˜2% of its surface. The dust environment is well known, producing a factor of ˜100 less dust than Halley. Comet References: [1] A'Hearn et al., ApJ 347, 1155, 1989 [2] Feldman and Festou, ACM 1991, p

  6. Organic Nano-Grains in Comet 103P/Hartley 2: The Organic Glue of Porous Aggregate Grains?

    Science.gov (United States)

    Wooden, D. H.; Russo, N.Dello; Li, A.; Woodward, C. E.; Kelley, M. S.; Harker, D. E.; Cook, J. C.; Vervack, R. J.; Geballe, T. R.

    2013-01-01

    organics studied as Insoluble Organic Matter in carbonaceous chondrites. Aliphatic coatings on submicron grains, however, will not be observable in absorption because they are fairly transparent, nor do the aliphatic carbonaceous coatings produce the 3.4 micron emission band because the particles they are attached to are too large (too many vibration modes). We must probe the nano-­-sized organic carriers that undergo substantive thermal fluctuations in cometary comae and emit at 3.3 3.4 micron. Observations of the 3.3 and 3.4 micron emission features contribute to characterizing the evolution of organics prior to their incorporation into cometary nuclei as well as their rapid evolution in cometary comae, which in turn contributes to deepening our understanding of the evolution of organics on the surfaces of asteroids and outer icy bodies in our solar system. Studying organics in comets contributes to understanding the formation and evolution pathways of ISM organics through to the formation of the robust insoluble organic matter in meteorites. A'Hearn, M.F., et al. 2011, Science, 332, 1396; Bockelee-­-Morvan, D. et al. 1995, Icarus, 116, 18; De Gregorio, B.T., et al. 2010, GCA, 74, 4454; Dello Russo, N., et al. 2011, ApJ, 734, L8; Dischler et al. 1983, Solid State Communications, 48, 105; Flynn, G., et al. 2010a, LPSC, 41, #1079; Flynn, G., et al. 2010b, COSPAR, 38, F31-­-0012-­-10; Flynn, G., Wirick, S. 2011, LPSC, 42, #1856; Fomenkova, et al. 1994, GCA 58, 4503; Matrajt, G., et al. 2013, ApJ, 765, 145; Schutte, et al. 1993, ApJ, 415, 397; Wooden, D.H. et al. 2011, EPSC-­-DPS, 1557; Wooden, D.H. et al. 2013, submitted.

  7. The peculiar case of Marosticano xenoliths: a cratonic mantle fragment affected by carbonatite metasomatism in the Veneto Volcanic Province (Northern Italy)

    Science.gov (United States)

    Brombin, Valentina; Bonadiman, Costanza; Coltorti, Massimo; Florencia Fahnestock, M.; Bryce, Julia G.; Marzoli, Andrea

    2017-04-01

    Province, Southern Alps. Geological Society of America, 131-152. Beccaluva L., Bonadiman C., Coltorti M., Salvini L., Siena F. (2001). Depletion events, nature of metasomatizing agent and timing of enrichment processes in lithospheric mantle xenoliths from the Veneto Volcanic Province. Journal of Petrology, 42, 173-187. Coltorti, M., Bonadiman, C., Hinton, R.W., Siena, F., Upton, B.G.J. (1999). Carbonatite metasomatism of the oceanic upper mantle: evidence from clinopyroxenes and glasses in ultramafic xenoliths of Grande Comore, Indian Ocean. Journal of Petrology, 40, 133-165. Downes, H., MacDonald, R., Upton, B.G.J., Cox, K.G, Bodinier, J-L, Mason, P.R.D, James, D., Hill, P.G., Hearn, C. Jr (2004). Ultramafic xenoliths from the Bearpaw Mountains, Montana, USA: evidence for multiple metasomatic events in the lithospheric mantle beneath the Wyoming Carton. Journal of Petrology, 45, 1631-1662. Foley, S.F. (2011). A reappraisal of redox melting in the Earth's mantle as a function of tectonic setting and time. Journal of Petrology, 52, 1363-1391. Gasperini D., Bosch D., Braga R., Bondi M., Macera P., Morten L. (2006). Ultramafic xenoliths from the Veneto Volcanic Province (Italy): Petrological and geochemical evidence for multiple metasomatism of the SE Alps mantle lithospere. Geochemical Journal, 40, 377-404. Kelemen, P.B., Hart, S.R., Bernstein, S. (1998). Silica enrichment in the continental upper mantle via melt/rock reaction. Earth and Planetary Science Letters, 164, 387-406. Ramsey, R.R, Tompkins, L.A. (1994). The geology, heavy mineral concentrate mineralogy, and diamond prospectivity of the Boa Esperança and Cana Verde pipes, Corrego D'anta, Minas Gerais, Brazil, in: Meyer, H.O.A and Leonardos, O.H. (Eds.), Proceeding of the Fifth International Kimberlite Conference 2. Companhia de Pesquisa de Recursors Minerais, Special Publications, 329-345. Siena F., Coltorti M. (1989). Lithospheric mantle evolution: evidences from ultramafic xenoliths in the Lessinean volcanics

  8. Preface: SciDAC 2005

    Science.gov (United States)

    Mezzacappa, Anthony

    2005-01-01

    in procurement and setting up and executing the contracts with the hotel, and to John Bui and John Smith for their superb wireless networking and A/V set up and support. We are grateful for the relentless efforts of all of these individuals, their remarkable talents, and for the joy of working with them during this past year. They were the cornerstones of SciDAC 2005. Thanks also go to Kymba A'Hearn and Patty Boyd for on-site registration, Brittany Hagen for administrative support, Bruce Johnston for netcast support, Tim Jones for help with the proceedings and Web site, Sherry Lamb for housing and registration, Cindy Lathum for Web site design, Carolyn Peters for on-site registration, and Dami Rich for graphic design. And we would like to express our appreciation to the Oak Ridge National Laboratory, especially Jeff Nichols, the Argonne National Laboratory, the Lawrence Berkeley National Laboratory, and to our corporate sponsors, Cray, IBM, Intel, and SGI, for their support. We would like to extend special thanks also to our plenary speakers, technical speakers, poster presenters, and panelists for all of their efforts on behalf of SciDAC 2005 and for their remarkable achievements and contributions. We would like to express our deep appreciation to Lali Chatterjee, Graham Douglas and Margaret Smith of Institute of Physics Publishing, who worked tirelessly in order to provide us with this finished volume within two months, which is nothing short of miraculous. Finally, we wish to express our heartfelt thanks to Michael Strayer, SciDAC Director, whose vision it was to focus SciDAC 2005 on scientific discovery, around which all of the excitement we experienced revolved, and to our DOE SciDAC program managers, especially Fred Johnson, for their support, input, and help throughout.