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1. Preface

Author

Elster C., Phillips D.R., and Roberts C.D.

Subjects
Physics, QC1-999
Published
2016
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2. Diquark correlations in hadron physics: Origin, impact and evidence

Author

Barabanov, M.Yu., Bedolla, M.A., Brooks, W.K., Cates, G.D., Chen, C., Chen, Y., Cisbani, E., Ding, M., Eichmann, G., Ent, R., Ferretti, J., Gothe, R.W., Horn, T., Liuti, S., Mezrag, C., Pilloni, A., Puckett, A.J.R., Roberts, C.D., Rossi, P., Salmé, G., Santopinto, E., Segovia, J., Syritsyn, S.N., Takizawa, M., Tomasi-Gustafsson, E., Wein, P., and Wojtsekhowski, B.B.

Published
2021
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6. Strong Interaction Physics at the Luminosity Frontier with 22 GeV Electrons at Jefferson Lab

Author

Accardi, A., Achenbach, P., Adhikari, D., Afanasev, A., Akondi, C.S., Akopov, N., Albaladejo, M., Albataineh, H., Albrecht, M., Almeida-Zamora, B., Amaryan, M., Androić, D., Armstrong, W., Armstrong, D.S., Arratia, M., Arrington, J., Asaturyan, A., Austregesilo, A., Avagyan, H., Averett, T., Ayerbe Gayoso, C., Bacchetta, A., Balantekin, A.B., Baltzell, N., Barion, L., Barry, P.C., Bashir, A., Battaglieri, M., Bellini, V., Belov, I., Benhar, O., Benkel, B., Benmokhtar, F., Bentz, W., Bertone, V., Bhatt, H., Bianconi, A., Bibrzycki, L., Bijker, R., Binosi, D., Biswas, D., Boër, M., Boeglin, W., Bogacz, S.A., Boglione, M., Bondí, M., Boos, E.E., Bosted, P., Bozzi, G., Brash, E.J., Briceño, R.A., Brindza, P.D., Briscoe, W.J., Brodsky, S.J., Brooks, W.K., Burkert, V.D., Camsonne, A., Cao, T., Cardman, L.S., Carman, D.S., Carpinelli, M., Cates, G.D., Caylor, J., Celentano, A., Celiberto, F.G., Cerutti, M., Chang, Lei, Chatagnon, P., Chen, C., Chen, J-P, Chetry, T., Christopher, A., Chudakov, E., Cisbani, E., Cloët, I.C., Cobos-Martinez, J.J., Cohen, E.O., Colangelo, P., Cole, P.L., Constantinou, M., Contalbrigo, M., Costantini, G., Cosyn, W., Cotton, C., Dusa, S. Covrig, Cui, Z.-F., D'Angelo, A., Döring, M., Dalton, M.M., Danilkin, I., Davydov, M., Day, D., De Fazio, F., De Napoli, M., De Vita, R., Dean, D.J., Defurne, M., Deur, M., Devkota, B., Dhital, S., Di Nezza, P., Diefenthaler, M., Diehl, S., Dilks, C., Ding, M., Djalali, C., Dobbs, S., Dupré, R., Dutta, D., Edwards, R.G., Egiyan, H., Ehinger, L., Eichmann, G., Elaasar, M., Elouadrhiri, L., El Alaoui, A., El Fassi, L., Emmert, A., Engelhardt, M., Ent, R., Ernst, D.J., Eugenio, P., Evans, G., Fanelli, C., Fegan, S., Fernández-Ramírez, C., Fernandez, L.A., Fernando, I.P., Filippi, A., Fischer, C.S., Fogler, C., Fomin, N., Frankfurt, L., Frederico, T., Freese, A., Fu, Y., Gamberg, L., Gan, L., Gao, F., Garcia-Tecocoatzi, H., Gaskell, D., Gasparian, A., Gates, K., Gavalian, G., Ghoshal, P.K., Giachino, A., Giacosa, F., Giannuzzi, F., Gilfoyle, G.-P., Girod, F-X, Glazier, D.I., Gleason, C., Godfrey, S., Goity, J.L., Golubenko, A.A., Gonzàlez-Solís, S., Gothe, R.W., Gotra, Y., Griffioen, K., Grocholski, O., Grube, B., Guèye, P., Guo, F.-K., Guo, Y., Guo, L., Hague, T.J., Hammoud, N., Hansen, J.-O., Hattawy, M., Hauenstein, F., Hayward, T., Heddle, D., Heinrich, N., Hen, O., Higinbotham, D.W., Higuera-Angulo, I.M., Hiller Blin, A.N., Hobart, A., Holmberg, D.E., Horn, T., Hoyer, P., Huber, G.M., Hurck, P., Hutauruk, P.T.P., Ilieva, Y., Illari, I., Ireland, D.G., Isupov, E.L., Italiano, A., Jaegle, I., Jarvis, N.S., Jenkins, DJ, Jeschonnek, S., Ji, C-R., Jo, H.S., Jones, M., Jones, R.T., Jones, D.C., Joo, K., Junaid, M., Kageya, T., Kalantarians, N., Karki, A., Karyan, G., Katramatou, A.T., Kay, S.J.D., Kazimi, R., Keith, C.D., Keppel, C., Kerbizi, A., Khachatryan, V., Khanal, A., Khandaker, M., Kim, A., Kinney, E.R., Kohl, M., Kotzinian, A., Kriesten, B.T., Kubarovsky, V., Kubis, B., Kuhn, S.E., Kumar, V., Kutz, T., Leali, M., Lebed, R.F., Lenisa, P., Leskovec, L., Li, S., Li, X., Liao, J., Lin, H.-W., Liu, L., Liuti, S., Liyanage, N., Lu, Y., MacGregor, I.J.D., Mack, D.J., Maiani, L., Mamo, K.A., Mandaglio, G., Mariani, C., Markowitz, P., Marukyan, H., Mascagna, V., Mathieu, V., Maxwell, J., Mazouz, M., McCaughan, M., McKeown, R.D., McKinnon, B., Meekins, D., Melnitchouk, W., Meyer, C.A., Meziani, Z.-E., Mezrag, C., Michaels, R., Miller, G.A., Mineeva, T., Miramontes, A.S., Mirazita, M., Mizutani, K., Mkrtchyan, H., Mkrtchyan, A., Moffit, B., Mohanmurthy, P., Mokeev, V.I., Monaghan, P., Montaña, G., Montgomery, R., Moretti, A., Chàvez, J.M. Morgado, Mosel, U., Movsisyan, A., Musico, P., Nadeeshani, S.A., Nakamura, S.X., Nazeer, J., Nefediev, A.V., Neupane, K., Nguyen, D., Niccolai, S., Niculescu, I., Niculescu, G., Nocera, E.R., Nycz, M., Olness, F.I., Ortega, P.G., Osipenko, M., Pace, E., Pandey, B., Pandey, P., Papandreou, Z., Papavassiliou, J., Pappalardo, L.L., Paredes-Torres, G., Paremuzyan, R., Park, S., Parsamyan, B., Paschke, K.D., Pasquini, B., Passemar, E., Pasyuk, E., Patel, T., Paudel, C., Paul, S.J., Peng, J-C., Pentchev, L., Perrino, R., Perry, R.J., Peters, K., Petratos, G.G., Piasetzky, E., Pilloni, A., Pire, B., Pitonyak, D., Pitt, M.L., Polosa, A.D., Pospelov, M., Postuma, A.C., Poudel, J., Preet, L., Prelovsek, S., Price, J.W., Prokudin, A., Puckett, A.J.R., Pybus, J.R., Qin, S.-X., Qiu, J.-W., Radici, M., Rashidi, H., Rathnayake, A.D., Raue, B.A., Reed, T., Reimer, P.E., Reinhold, J., Richard, J.-M., Rinaldi, M., Ringer, F., Ripani, M., Ritman, J., Rittenhouse West, J., Rivero-Acosta, A., Roberts, C.D., Rodas, A., Rodini, S., Rodríguez-Quintero, J., Rogers, T.C., Rojo, J., Rossi, P., Rossi, G.C., Salmè, G., Santiesteban, S.N., Santopinto, E., Sargsian, M., Sato, N., Schadmand, S., Schmidt, A., Schmidt, S.M., Schnell, G., Schumacher, R.A., Schweitzer, P., Scimemi, I., Scott, K.C., Seay, D.A., Segovia, J., Semenov-Tian-Shansky, K., Seryi, A., Sharda, A.S., Shepherd, M.R., Shirokov, E.V., Shrestha, S., Shrestha, U., Signori, A., Slifer, K.J., Smith, W.A., Somov, A., Souder, P., Sparveris, N., Spizzo, F., Spreafico, M., Stepanyan, S., Stevens, J.R., Strakovsky, I.I., Strauch, S., Strikman, M., Su, S., Sumner, B.C.L., Sun, E., Suresh, M., Sutera, C., Swanson, E.S., Szczepaniak, A.P., Sznajder, P., Szumila-Vance, H., Szymanowski, L., Tadepalli, A.-S., Tadevosyan, V., Tamang, B., Tarasov, V.V., Thiel, A., Tong, X.-B., Tyson, R., Ungaro, M., Urciuoli, G.M., Usman, A., Valcarce, A., Vallarino, S., Vaquera-Araujo, C.A., Venturelli, L., Vera, F., Vladimirov, A., Vossen, A., Wagner, J., Wei, X., Weinstein, L.B., Weiss, C., Williams, R., Winney, D., Wojtsekhowski, B., Wood, M.H., Xiao, T., Xu, S.-S., Ye, Z., Yero, C., Yurov, M., Zachariou, N., Zhang, Z., Zhao, Z.W., Zhao, Y., Zheng, X., Zhou, X., Ziegler, V., Zihlmann, B., de Paula, W., de Téramond, G.F., Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Centre de Physique Théorique [Palaiseau] (CPHT), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), National Center for Nuclear Research [Warsaw] (NCBJ), and National Center for Nuclear Research (NCBJ)

Subjects
nucl-th, Nuclear Theory, hep-ex, FOS: Physical sciences, hep-ph, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], nucl-ex, High Energy Physics - Experiment, Nuclear Theory (nucl-th), High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), Nuclear Physics - Theory, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], Nuclear Physics - Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment, Particle Physics - Experiment, Particle Physics - Phenomenology
Abstract

This document presents the initial scientific case for upgrading the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab (JLab) to 22 GeV. It is the result of a community effort, incorporating insights from a series of workshops conducted between March 2022 and April 2023. With a track record of over 25 years in delivering the world's most intense and precise multi-GeV electron beams, CEBAF's potential for a higher energy upgrade presents a unique opportunity for an innovative nuclear physics program, which seamlessly integrates a rich historical background with a promising future. The proposed physics program encompass a diverse range of investigations centered around the nonperturbative dynamics inherent in hadron structure and the exploration of strongly interacting systems. It builds upon the exceptional capabilities of CEBAF in high-luminosity operations, the availability of existing or planned Hall equipment, and recent advancements in accelerator technology. The proposed program cover various scientific topics, including Hadron Spectroscopy, Partonic Structure and Spin, Hadronization and Transverse Momentum, Spatial Structure, Mechanical Properties, Form Factors and Emergent Hadron Mass, Hadron-Quark Transition, and Nuclear Dynamics at Extreme Conditions, as well as QCD Confinement and Fundamental Symmetries. Each topic highlights the key measurements achievable at a 22 GeV CEBAF accelerator. Furthermore, this document outlines the significant physics outcomes and unique aspects of these programs that distinguish them from other existing or planned facilities. In summary, this document provides an exciting rationale for the energy upgrade of CEBAF to 22 GeV, outlining the transformative scientific potential that lies within reach, and the remarkable opportunities it offers for advancing our understanding of hadron physics and related fundamental phenomena.

Published
2023

10. First multidimensional, high precision measurements of semi-inclusive $\pi^+$ beam single spin asymmetries from the proton over a wide range of kinematics

Author

DIEHL, S., KIM, A., ANGELINI, G., JOO, K., ADHIKARI, S., AMARYAN, M., ARRATIA, M., ATAC, H., AVAKIAN, H., GAYOSO, C. Ayerbe, BALTZELL, N.A., BARION, L., BASTAMI, S., BATTAGLIERI, M., BEDLINSKIY, I., BENMOKHTAR, F., BIANCONI, A., BISELLI, A.S., BONDI, M., BOSSÙ, F., BOIARINOV, S., BRINKMANN, K.-T., BRISCOE, W.J., BROOKS, W., BULUMULLA, D., BURKERT, V.D., CARMAN, D.S., CARVAJAL, J.C., CELENTANO, A., CHATAGNON, P., CHETRY, T., CIULLO, G., CLARK, L., CLARY, B.A., COLE, P.L., CONTALBRIGO, M., COSTANTINI, G., CREDE, V., D'ANGELO, A., DASHYAN, N., DE VITA, R., DEFURNE, M., DEUR, A., DILKS, C., DJALALI, C., DUGGER, M., DUPRE, R., EHRHART, M., ALAOUI, A. El, FASSI, L. El, ELOUADRHIRI, L., FEGAN, S., FILIPPI, A., FOREST, T., GAVALIAN, G., GILFOYLE, G.P., GIROD, F.X., GLAZIER, D.I., GOLUBENKO, A.A., GOTHE, R.W., GOTRA, Y., GRIFFIOEN, K.A., GUIDAL, M., HAFIDI, K., HAKOBYAN, H., HATTAWY, M., HAYWARD, T.B., HEDDLE, D., HICKS, K., HOBART, A., HOLTROP, M., HYDE, C.E., IRELAND, D.G., ISUPOV, E.L., JO, H.S., JOHNSTON, R., JOOSTEN, S., KELLER, D., KHACHATRYAN, M., KHANAL, A., KIM, W., KRIPKO, A., KUBAROVSKY, V., KUHN, S.E., LANZA, L., LEALI, M., LEE, S., LENISA, P., LIVINGSTON, K., LU, Z., MACGREGOR, I.J.D., MARCHAND, D., MARKOV, N., MARSICANO, L., MASCAGNA, V., MCKINNON, B., MEZIANI, Z.E., MILNER, R.G., MINEEVA, T., MIRAZITA, M., MOKEEV, V., MORAN, P., MOVSISYAN, A., MUNOZ CAMACHO, C., NADEL-TURONSKI, P., NAIDOO, P., NEUPANE, K., NICCOLAI, S., NICULESCU, G., O'CONNELL, T.R., OSIPENKO, M., PAOLONE, M., PAPPALARDO, L.L., PAREMUZYAN, R., PASYUK, E., PHELPS, W., POGORELKO, O., PROK, Y., PROKUDIN, A., RAUE, B.A., RIPANI, M., RITMAN, J., RIZZO, A., ROBERTS, C.D., ROSSI, P., ROWLEY, J., SABATIÉ, F., SALGADO, C., SCHMIDT, A., SEGARRA, E.P., SHARABIAN, Y.G., SHRESTHA, U., SOTO, O., SPARVERIS, N., STEPANYAN, S., STOLER, P., STRAKOVSKY, I.I., STRAUCH, S., TEZGIN, K., THORNTON, A., TYLER, N., TYSON, R., UNGARO, M., VENTURELLI, L., VOSKANYAN, H., VOSSEN, A., VOUTIER, E., WATTS, D.P., WEI, K., WEI, X., XU, S.-S., YALE, B., ZACHARIOU, N., ZHANG, J., Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and CLAS

Subjects
deep inelastic scattering: semi-inclusive reaction, precision measurement, nucleon, pi+: electroproduction, parton: distribution function, structure function: ratio, polarized beam, quark gluon: correlation, transverse momentum dependence, kinematics, CLAS, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Physics::Experiment, twist: 3, electron: beam, higher-dimensional, Nuclear Experiment, spin: asymmetry, experimental results, Jefferson Lab
Abstract

High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here the first multidimensional study of single $\pi^+$ SIDIS data over a large kinematic range in $z$, $x_B$, $P_T$ and virtualities $Q^2$ ranging from 1 GeV$^2$ up to 7 GeV$^2$. In particular, the structure function ratio $F_{LU}^{\sin\phi}/F_{UU}$ has been determined, where $F_{LU}^{\sin\phi}$ is a twist-3 quantity that can reveal novel properties of quark-gluon correlations within the nucleon. The impact of the data on the evolving understanding of the underlying reaction mechanisms and their kinematic variation is explored using theoretical models for the different contributing transverse momentum dependent parton distribution functions.

Published
2021

11. Ribeiroia ondatrae causes limb abnormalities in a Canadian amphibian community

Author

Roberts, C.D. and Dickinson, T.E.

Subjects
Extremities (Anatomy) -- Physiological aspects -- Health aspects, Amphibians -- Physiological aspects -- Diseases and pests, Platyhelminthes -- Physiological aspects -- Health aspects, Host-parasite relationships -- Health aspects, Zoology and wildlife conservation
Abstract

A parasitic flatworm (Ribeiroia ondatrae Price, 1931) is known to cause severe limb abnormalities and high mortality levels in American amphibian populations. The distributional pattern of this parasite--its main dispersal agent being birds--correlates with the boundaries of migratory flyways in the USA. Yet thus far, R. ondatrae have not been found in Canadian amphibians, which is surprising, considering that said flyways extend well into northern Canada. In this study, we report on a lake in British Columbia that is known to support amphibians with abnormalities similar to those induced by R. ondatrae. To determine if the parasite was present and if it was the cause of the abnormalities, we collected and necropsied metamorphs of the Columbia Spotted Frog (Rana luteiventris Thompson, 1913) and the Pacific Chorus Frog (Pseudacris regilla (Baird and Girard, 1852)), and we set up field enclosures to protect larvae from R. ondatrae. Abnormality levels were high in both species (>20%), with the vast majority being found in close proximity to the metacercariae of R. ondatrae. Moreover, the types of abnormalities closely matched those previously recorded in field and laboratory exposures of amphibians to R. ondatrae. Finally, larvae that developed in the same lake, but were protected from R. ondatrae by an enclosure, did not develop abnormalities. Collectively, these results demonstrate that R. ondatrae are both present in an amphibian community in Canada and responsible for causing limb abnormalities. Key words: abnormalities, deformities, Columbia Spotted Frog (Rana luteiventris), Pacific Chorus Frog (Pseudacris regilla), Ribeiroia ondatrae. Un ver plat parasite (Ribeiroia ondatrae Price, 1931) est la cause de graves anomalies des membres et de forts taux de mortalite dans les populations americaines d'amphibiens. Les oiseaux constituant son principal vecteur de dispersion, le schema de repartition geographique de ce parasite est correle aux limites des routes de migration aux Etats-Unis. Pourtant, a ce jour, aucun R. ondatrae n'a ete trouve dans des amphibiens canadiens, ce qui est surprenant etant donne que ces routes de migration se prolongent jusqu'au Canada septentrional. Nous faisons etat d'un lac en Colombie-Britannique qui supporte des amphibiens presentant des anomalies semblables a celles que produit R. ondatrae. Pour determiner si ce parasite est present et s il est la cause des anomalies, nous avons preleve des metamorphes de grenouille maculee du Columbia (Rana luteiventris Thompson, 1913) et de rainette du Pacifique (Pseudacris regilla (Baird et Girard, 1852)), avons procede a leur necropsie et avons etabli des enclos sur le terrain pour en proteger les larves contre R. ondatrae. Les taux d'anomalies etaient eleves chez les deux especes (>20 %), la grande majorite ayant ete prelevee a proximite de metacercaires de R. ondatrae. En outre, les types d'anomalies correspondaient de pres aux anomalies relevees par le passe dans des cas d'exposition d'amphibiens a R. ondatrae sur le terrain et en laboratoire. Enfin, les larves qui se sont developpees dans le meme lac, mais a l'abri de R. ondatrae dans un enclos, ne presentaient pas d'anomalies. L'ensemble de ces resultats demontre que R. ondatrae est present dans une communaute d amphibiens au Canada et qu il est la cause d anomalies des membres chez des amphibiens. Mots-cles : anomalies, malformations, grenouille maculee du Columbia (Rana luteiventris), rainette du Pacifique (Pseudacris regilla), Ribeiroia ondatrae. [Traduit par la Redaction], Introduction In any vertebrate population only a small percentage of individuals should have morphological abnormalities. For instance, historical data suggest that amphibian populations should have an abnormality level below 5% [...]

Published
2012
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18. Strong QCD from Hadron Structure Experiments: Newport News, VA, USA, November 4-8, 2019

Author

Brodsky, S.J., Burkert, V.D., Carman, D.S., Chen, J.P., Cui, Z.-F., Döring, M., Dosch, H.G., Draayer, J., Elouadrhiri, L., Glazier, D.I., Hiller Blin, A.N., Horn, T., Joo, K., Kim, H.C., Kubarovsky, V., Kuhn, S.E., Lu, Y., Melnitchouk, W., Mezrag, C., Mokeev, V.I., Qiu, J.W., Radici, M., Richards, D., Roberts, C.D., Rodríguez-Quintero, J., Segovia, J., Szczepaniak, A.P., de Téramond, G.F., Winney, D., Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay

Subjects
[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], High Energy Physics::Lattice, hadron spectroscopy and structure, Nuclear Theory, hadron: mass, parton: distribution function, emergence of hadronic mass, nonperturbative, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], hadron: excited state, hadron: structure, parton: distribution amplitude, hadron elastic form factors, 12.38.Aw, strong coupling, quantum chromodynamics, 14.20.Gk, meson: production, strong (non-perturbative) QCD, Nuclear Experiment, Higgs mechanism, quark gluon, activity report, dynamical chiral symmetry breaking, parton distribution amplitudes and functions, 13.40.Gp, [PHYS.HLAT]Physics [physics]/High Energy Physics - Lattice [hep-lat], hadron spectroscopy, High Energy Physics::Phenomenology, nucleus, symmetry breaking: chiral, quasiparticle, electron nucleon: colliding beams, form factor: electromagnetic, baryon resonance: production, confinement, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], Dyson–Schwinger equations, meson: form factor, Confinement of gluons and quarks, High Energy Physics::Experiment, 13.60.Le, Jefferson Lab
Abstract

International audience; The topical workshop Strong QCD from Hadron Structure Experiments took place at Jefferson Lab from November 6–9, 2019. Impressive progress in relating hadron structure observables to the strong QCD mechanisms has been achieved from the ab initio QCD description of hadron structure in a diverse array of methods in order to expose emergent phenomena via quasi-particle formation. The wealth of experimental data and the advances in hadron structure theory make it possible to gain insight into strong interaction dynamics in the regime of large quark–gluon coupling (the strong QCD regime), which will address the most challenging problems of the Standard Model on the nature of the dominant part of hadron mass, quark–gluon confinement, and the emergence of the ground and excited state hadrons, as well as atomic nuclei, from QCD. This workshop aimed to develop plans and to facilitate the future synergistic efforts between experimentalists, phenomenologists, and theorists working on studies of hadron spectroscopy and structure with the goal to connect the properties of hadrons and atomic nuclei available from data to the strong QCD dynamics underlying their emergence from QCD. These results pave the way for a future breakthrough extension in the studies of QCD with an Electron–Ion Collider in the U.S.

Published
2019
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19. Detecting a forced signal in satellite-era sea-level change

Author

Richter, K., Meyssignac, B., Slangen, A.B.A., Melet, A., Church, J.A., Fettweis, X., Marzeion, B., Agosta, C., Ligtenberg, S.R.M., Spada, G., Palmer, M.D., Roberts, C.D., Champollion, N., Richter, K., Meyssignac, B., Slangen, A.B.A., Melet, A., Church, J.A., Fettweis, X., Marzeion, B., Agosta, C., Ligtenberg, S.R.M., Spada, G., Palmer, M.D., Roberts, C.D., and Champollion, N.

Abstract

In this study, we compare the spatial patterns of simulated geocentric sea-level change to observations from satellite altimetry over the period 1993–2015 to assess whether a forced signal is detectable. This is challenging, as on these time scales internal variability plays an important role and may dominate the observed spatial patterns of regional sea-level change. Model simulations of regional sea-level change associated with sterodynamic sea level, atmospheric loading, glacier mass change, and ice-sheet surface mass balance changes are combined with observations of groundwater depletion, reservoir storage, and dynamic ice-sheet mass changes. The resulting total geocentric regional sea-level change is then compared to independent measurements from satellite altimeter observations. The detectability of the climate-forced signal is assessed by comparing the model ensemble mean of the 'historical' simulations with the characteristics of sea-level variability in pre-industrial control simulations. To further minimize the impact of internal variability, zonal averages were produced. We find that, in all ocean basins, zonally averaged simulated sea-level changes are consistent with observations within sampling uncertainties associated with simulated internal variability of the sterodynamic component. Furthermore, the simulated zonally averaged sea-level change cannot be explained by internal variability alone—thus we conclude that the observations include a forced contribution that is detectable at basin scales.

Published
2020

20. Exploring the drivers of global and local sea‐level change over the 21st century and beyond

Author

Palmer, M.D., Gregory, J.M., Bagge, M., Calvert, D., Hagedoorn, J.M., Howard, T., Klemann, V., Lowe, J.A., Roberts, C.D., Slangen, A.B.A., Spada, G., Palmer, M.D., Gregory, J.M., Bagge, M., Calvert, D., Hagedoorn, J.M., Howard, T., Klemann, V., Lowe, J.A., Roberts, C.D., Slangen, A.B.A., and Spada, G.

Abstract

We present a new set of global and local sea‐level projections at example tide gauge locations under the RCP2.6, RCP4.5, and RCP8.5 emissions scenarios. Compared to the CMIP5‐based sea‐level projections presented in IPCC AR5, we introduce a number of methodological innovations, including (i) more comprehensive treatment of uncertainties, (ii) direct traceability between global and local projections, and (iii) exploratory extended projections to 2300 based on emulation of individual CMIP5 models. Combining the projections with observed tide gauge records, we explore the contribution to total variance that arises from sea‐level variability, different emissions scenarios, and model uncertainty. For the period out to 2300 we further breakdown the model uncertainty by sea‐level component and consider the dependence on geographic location, time horizon, and emissions scenario. Our analysis highlights the importance of local variability for sea‐level change in the coming decades and the potential value of annual‐to‐decadal predictions of local sea‐level change. Projections to 2300 show a substantial degree of committed sea‐level rise under all emissions scenarios considered and highlight the reduced future risk associated with RCP2.6 and RCP4.5 compared to RCP8.5. Tide gauge locations can show large ( > 50%) departures from the global average, in some cases even reversing the sign of the change. While uncertainty in projections of the future Antarctic ice dynamic response tends to dominate post‐2100, we see substantial differences in the breakdown of model variance as a function of location, time scale, and emissions scenario.

Published
2020

21. Northern Hemisphere blocking simulation in current climate models: evaluating progress from the Climate Model Intercomparison Project Phase 5 to 6 and sensitivity to resolution

Author

Ministerio de Economía y Competitividad (España), Schiemann R., Athanasiadis P., Barriopedro, David, Doblas-Reyes F., Lohmann K., Roberts M.J., Sein D.V., Roberts C.D., Terray L., Ministerio de Economía y Competitividad (España), Schiemann R., Athanasiadis P., Barriopedro, David, Doblas-Reyes F., Lohmann K., Roberts M.J., Sein D.V., Roberts C.D., and Terray L.

Abstract

Global climate models (GCMs) are known to suffer from biases in the simulation of atmospheric blocking, and this study provides an assessment of how blocking is represented by the latest generation of GCMs. It is evaluated (i) how historical CMIP6 (Climate Model Intercomparison Project Phase 6) simulations perform compared to CMIP5 simulations and (ii) how horizontal model resolution affects the simulation of blocking in the CMIP6-HighResMIP (PRIMAVERA ¿ PRocess-based climate sIMulation: AdVances in high-resolution modelling and European climate Risk Assessment) model ensemble, which is designed to address this type of question. Two blocking indices are used to evaluate the simulated mean blocking frequency and blocking persistence for the Euro-Atlantic and Pacific regions in winter and summer against the corresponding estimates from atmospheric reanalysis data. There is robust evidence that CMIP6 models simulate blocking frequency and persistence better than CMIP5 models in the Atlantic and Pacific and during winter and summer. This improvement is sizeable so that, for example, winter blocking frequency in the median CMIP5 model in a large Euro-Atlantic domain is underestimated by 33% using the absolute geopotential height (AGP) blocking index, whereas the same number is 18% for the median CMIP6 model. As for the sensitivity of simulated blocking to resolution, it is found that the resolution increase, from typically 100 to 20 km grid spacing, in most of the PRIMAVERA models, which are not re-tuned at the higher resolutions, benefits the mean blocking frequency in the Atlantic in winter and summer and in the Pacific in summer. Simulated blocking persistence, however, is not seen to improve with resolution. Our results are consistent with previous studies suggesting that resolution is one of a number of interacting factors necessary for an adequate simulation of blocking in GCMs. The improvements reported in this study hold promise for further reductions in blocking

Published
2020

25. Evaluating model simulations of 20th century sea-level rise. Part 1: Global mean sea-level change

Author

Slangen, A.B.A., Meyssignac, B., Agosta, C., Champollion, N., Church, J.A., Fettweis, X., Ligtenberg, S.R.M., Marzeion, B., Melet, A., Palmer, M.D., Richter, K., Roberts, C.D., Spada, G., Slangen, Aimée B. A., Meyssignac, Benoit, Agosta, Cecile, Champollion, Nicola, Church, John A., Fettweis, Xavier, Ligtenberg, Stefan R. M., Marzeion, Ben, Melet, Angelique, Palmer, Matthew D., Richter, Kristin, Roberts, Christopher D., and SPADA, GIORGIO

Subjects
Ocean, Sea level, Climate change, Altimetry, Climate models, Model comparison, Climate model
Abstract

Sea-level change is one of the major consequences of climate change and is projected to affect coastal communities around the world. Here, we compare Global Mean Sea-Level (GMSL) change estimated by 12 climate models from the 5th phase of the World Climate Research Programme’s Climate Model Intercomparison Project (CMIP5) to observational estimates for the period 1900-2015. We analyse observed and simulated individual contributions to GMSL change (thermal expansion, glacier mass change, ice sheet mass change, landwater storage change) and compare the summed simulated contributions to observed GMSL change over the period 1900-2007 using tide gauge reconstructions, and over the period 1993-2015 using satellite altimetry estimates. The model-simulated contributions allow us to explain 50 ± 30% (uncertainties 1.65σ unless indicated otherwise) of the mean observed change from 1901-1920 to 1988-2007. Based on attributable biases between observations and models, we propose to add a number of corrections, which result in an improved explanation of 75 ± 38% of the observed change. For the satellite era (1993-1997 to 2011-2015) we find an improved budget closure of 102 ± 33% (105 ± 35% when including the proposed bias corrections). Simulated decadal trends over the 20th century increase, both in the thermal expansion and the combined mass contributions (glaciers, ice sheets and landwater storage). The mass components explain the majority of sea-level rise over the 20th century, but the thermal expansion has increasingly contributed to sea-level rise, starting from 1910 onwards and in 2015 accounting for 46% of the total simulated sea-level change.

Published
2017
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27. $\alpha$ clustering in Ti isotopes: $^{40,44,48}$Ca + $\alpha$ resonant scattering

Author

Bailey, S., Freer, M., Kokalova, T., Wheldon, C., Smith, R., Walshe, J., Prepolec, L., Soić, N., Tokić, V., Marqués, F.M., Achouri, N.L., Delaunay, F., Pârlog, M., Deshayes, Q., Fernández-Dominguez, B., Jacquot, B., Elster, C., Phillips, D.R., Roberts, C.D., Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
Physics, Isotope, Inverse kinematics, 010308 nuclear & particles physics, QC1-999, Astrophysics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Molecular physics, Resonant scattering, 0103 physical sciences, 010306 general physics, Cluster analysis
Abstract

Expérience GANIL; International audience; Measurements were made of the 4He(40,44,48Ca,α) resonant scattering reactions at 180° and up to Ec.m. ~ 11.5MeV, using the Thick Target Inverse Kinematics technique. These measurements are discussed, with a focus on assessing their usefulness for investigating α-clustering in medium mass 44,48,52Ti nuclei

Published
2015
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28. Direct Bethe-Salpeter solutions in Minkowski space

Author

Carbonell, J., Karmanov, V.A., Elster, C., Phillips, D.R., Roberts, C.D., Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
High Energy Physics - Theory, Nuclear Theory, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], QC1-999, FOS: Physical sciences, 01 natural sciences, Nuclear Theory (nucl-th), High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, Minkowski space, 010306 general physics, Mathematical physics, Boson, Physics, Kernel (set theory), 010308 nuclear & particles physics, Scattering, [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th], Propagator, State (functional analysis), Scattering amplitude, High Energy Physics - Phenomenology, High Energy Physics - Theory (hep-th), [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], Gravitational singularity
Abstract

We review a method to directly solve the Bethe-Salpeter equation in Minkowski space, both for bound and scattering states. It is based on a proper treatment of the many singularities which appear in the kernel and propagators. The off-mass shell scattering amplitude for spinless particles interacting by a one boson exchange was computed for the first time. Using our Minkowski space solutions for the initial (bound) and final (scattering) states, we calculate elastic and transition (bound to scattering state) electromagnetic form factors. The conservation of the transition electromagnetic current J.q=0, verified numerically, confirms the validity of our solutions., Comment: 4 pages, 4 figures, contribution to 21st International Conference on Few-Body Problems in Physics, Chicago, USA, May 18-21, 2015. To be published by EPJ Web of Conferences

Published
2015
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29. Spectroscopy of 17C via one-neutron knockout reaction

Author

Kim, S., Hwang, J., Satou, Y., Orr, N.A., Nakamura, T., Kondo, Y., Gibelin, J., Achouri, N.L., Aumann, T., Baba, H., Delaunay, F., Doornenbal, P., Fukuda, N., Inabe, N., Isobe, T., Kameda, D., Kanno, D., Kobayashi, N., Kobayashi, T., Kubo, T., Leblond, S., Lee, J., Marqués, F.M., Minakata, R., Motobayashi, T., Murai, D., Murakami, T., Muto, K., Nakashima, T., Nakatsuka, N., Navin, A., Nishi, S., Ogoshi, S., Otsu, H., Sato, H., Shimizu, Y., Suzuki, H., Takahashi, K., Takeda, H., Takeuchi, S., Tanaka, R., Togano, Y., Tuff, A.G., Vandebrouck, M., Yoneda, K.I., Elster, C., Phillips, D.R., Roberts, C.D., Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Physics, 010308 nuclear & particles physics, QC1-999, chemistry.chemical_element, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Nuclear physics, chemistry, 0103 physical sciences, Neutron, Atomic physics, 010306 general physics, Spectroscopy, Carbon, Excitation
Abstract

This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.; International audience; A spectroscopic study of 17C was performed via the one-neutron knockout reaction of 18C on a carbon target at RIKEN-RIBF. Three unbound states at excitation energies of 2.66(2), 3.16(5), and 3.97(3) MeV (preliminary) were observed. The energies are compared with shell-model calculations and existing measurements to deduce their spin-parities. From the comparison, the states at 2.66(2) and 3.97(3) MeV are suggested to be 1/2− and 3/2−, respectively. From its decay property, the state at 3.16(5) MeV is indicated to be 9/2+.

Published
2015
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30. Evaluating model simulations of twentieth-century sea-level rise. Part II: regional sea-level changes

Author

Meyssignac, B., Slangen, A.B.A., Melet, A., Church, J.A., Fettweis, X., Marzeion, B., Agosta, C., Ligtenberg, S.R.M., Spada, G., Richter, K., Palmer, M.D., Roberts, C.D., Champollion, N., Meyssignac, B., Slangen, A.B.A., Melet, A., Church, J.A., Fettweis, X., Marzeion, B., Agosta, C., Ligtenberg, S.R.M., Spada, G., Richter, K., Palmer, M.D., Roberts, C.D., and Champollion, N.

Abstract

Twentieth-century regional sea level changes are estimated from 12 climate models from phase 5 of the Climate Model Intercomparison Project (CMIP5). The output of the CMIP5 climate model simulations was used to calculate the global and regional sea level changes associated with dynamic sea level, atmospheric loading, glacier mass changes, and ice sheet surface mass balance contributions. The contribution from groundwater depletion, reservoir storage, and dynamic ice sheet mass changes are estimated from observations as they are not simulated by climate models. All contributions are summed, including the glacial isostatic adjustment (GIA) contribution, and compared to observational estimates from 27 tide gauge records over the twentieth century (1900–2015). A general agreement is found between the simulated sea level and tide gauge records in terms of interannual to multidecadal variability over 1900–2015. But climate models tend to systematically underestimate the observed sea level trends, particularly in the first half of the twentieth century. The corrections based on attributable biases between observations and models that have been identified in Part I of this two-part paper result in an improved explanation of the spatial variability in observed sea level trends by climate models. Climate models show that the spatial variability in sea level trends observed by tide gauge records is dominated by the GIA contribution and the steric contribution over 1900–2015. Climate models also show that it is important to include all contributions to sea level changes as they cause significant local deviations; note, for example, the groundwater depletion around India, which is responsible for the low twentieth-century sea level rise in the region.

Published
2017

31. Atlantic Meridonal Overturning Circulation

Author

Frost, M., Baxter, J., Buckley, P., Dye, S., Stoker, B., McCarthy, G.D., Smeed, D.A., Cunningham, S.A., Roberts, C.D., Frost, M., Baxter, J., Buckley, P., Dye, S., Stoker, B., McCarthy, G.D., Smeed, D.A., Cunningham, S.A., and Roberts, C.D.

Published
2017

33. Atmosphere drives recent interannual variability of the Atlantic meridional overturning circulation at 26.5°N

Author

Roberts, C.D., Waters, J., Peterson, K.A., Palmer, M.D., McCarthy, G.D., Frajka-Williams, E., Haines, K., Lea, D.J., Martin, M.J., Storkey, D., Blockley, E.W., Zuo, H., Roberts, C.D., Waters, J., Peterson, K.A., Palmer, M.D., McCarthy, G.D., Frajka-Williams, E., Haines, K., Lea, D.J., Martin, M.J., Storkey, D., Blockley, E.W., and Zuo, H.

Abstract

The Atlantic meridional overturning circulation (AMOC) has been observed at 26.5°N since 2004. During 2009/2010, there was a transient 30% weakening of the AMOC driven by anomalies in geostrophic and Ekman transports. Here, we use simulations based on the Met Office Forecast Ocean Assimilation Model (FOAM) to diagnose the relative importance of atmospheric forcings and internal ocean dynamics in driving the anomalous geostrophic circulation of 2009/2010. Data-assimilating experiments with FOAM accurately reproduce the mean strength and depth of the AMOC at 26.5°N. In addition, agreement between simulated and observed stream functions in the deep ocean is improved when we calculate the AMOC using a method that approximates the observing array at 26.5°N. The main features of the geostrophic circulation anomaly are captured by an ensemble of simulations without data assimilation. These model results suggest that the atmosphere played a dominant role in driving recent interannual variability of the AMOC.

Published
2013

34. Observed Interannual Variability of the Atlantic Meridional Overturning Circulation at 26.5N

Author

McCarthy, G., Frajka-Williams, E., Johns, W.E., Baringer, M.O., Meinen, C.S., Bryden, H.L., Rayner, D., Duchez, A., Roberts, C.D., Cunningham, S.A., McCarthy, G., Frajka-Williams, E., Johns, W.E., Baringer, M.O., Meinen, C.S., Bryden, H.L., Rayner, D., Duchez, A., Roberts, C.D., and Cunningham, S.A.

Abstract

The Atlantic meridional overturning circulation (MOC) plays a critical role in the climate system and is responsible for much of the heat transported by the ocean. A mooring array, nomianally at 26$^\circ$N between the Bahamas and the Canary Islands, deployed in Apr 2004 provides continuous measurements of the strength and variability of this circulation. With seven full years of measurements, we now examine the interannual variability of the MOC. While earlier results highlighted substantial seasonal and shorter timescale variability, there had not been significant interannual variability. The mean MOC from 1 Apr 2004 to the 31 March 2009 was 18.5 Sv with the annual means having a standard deviation of only 1.0 Sv. From 1 April 2009 to 31 March 2010, the annually averaged MOC strength was just 12.8 Sv, representing a 30\% decline. This downturn persisted from early 2009 to mid-2010. We show that the cause of the decline was not only an anomalous wind-driven event from Dec 2009--Mar 2010 but also a strengthening of the geostrophic flow. In particular, the southward flow in the top 1100~m intensified, while the deep southward return transport---particularly in the deepest layer from 3000--5000~m---weakened. This rebalancing of the transport from the deep overturning to the upper gyre has implications for the heat transported by the Atlantic.

Published
2012

35. O-41 - Intravascular food reward

Author

Oliveira-Maia, A., primary, Roberts, C.D., additional, Walker, Q.D., additional, Luo, B., additional, Kuhn, C., additional, Simon, S.A., additional, and Nicolelis, M.A.L., additional

Published
2012
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49. Introduction

Author

Hill, R.N., primary, Chambers, W.A., additional, Green, S., additional, Gupta, K.C., additional, Hurley, P.M., additional, Lambert, L.A., additional, Lee, C.C., additional, Lee, J.K., additional, Liu, P.T., additional, Lowther, D.K., additional, Roberts, C.D., additional, Seabaugh, V.M., additional, Springer, J.A., additional, and Wilcox, N.L., additional

Published
1993
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50. Scoring for eye irritation tests

Author

Chambers, W.A., primary, Green, S., additional, Gupta, K.C., additional, Hill, R.N., additional, Huntley, K., additional, Hurley, P.M., additional, Lambert, L.A., additional, Lee, C.C., additional, Lee, J.K., additional, Liu, P.T., additional, Lowther, D.K., additional, Roberts, C.D., additional, Seabaugh, V.M., additional, Springer, J.A., additional, and Wilcox, N.L., additional

Published
1993
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