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1. Dalitz plot analysis of the D + → K − K + K + decay

Author

The LHCb collaboration, R. Aaij, C. Abellán Beteta, B. Adeva, M. Adinolfi, C. A. Aidala, Z. Ajaltouni, S. Akar, P. Albicocco, J. Albrecht, F. Alessio, M. Alexander, A. Alfonso Albero, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves, S. Amato, S. Amerio, Y. Amhis, L. An, L. Anderlini, G. Andreassi, M. Andreotti, J. E. Andrews, F. Archilli, P. d’Argent, J. Arnau Romeu, A. Artamonov, M. Artuso, K. Arzymatov, E. Aslanides, M. Atzeni, B. Audurier, S. Bachmann, J. J. Back, S. Baker, V. Balagura, W. Baldini, A. Baranov, R. J. Barlow, G. C. Barrand, S. Barsuk, W. Barter, M. Bartolini, F. Baryshnikov, V. Batozskaya, B. Batsukh, A. Battig, V. Battista, A. Bay, J. Beddow, F. Bedeschi, I. Bediaga, A. Beiter, L. J. Bel, S. Belin, N. Beliy, V. Bellee, N. Belloli, K. Belous, I. Belyaev, E. Ben-Haim, G. Bencivenni, S. Benson, S. Beranek, A. Berezhnoy, R. Bernet, D. Berninghoff, E. Bertholet, A. Bertolin, C. Betancourt, F. Betti, M. O. Bettler, M. van Beuzekom, Ia. Bezshyiko, S. Bhasin, J. Bhom, S. Bifani, P. Billoir, A. Birnkraut, A. Bizzeti, M. Bjørn, M. P. Blago, T. Blake, F. Blanc, S. Blusk, D. Bobulska, V. Bocci, O. Boente Garcia, T. Boettcher, A. Bondar, N. Bondar, S. Borghi, M. Borisyak, M. Borsato, F. Bossu, M. Boubdir, T. J. V. Bowcock, C. Bozzi, S. Braun, M. Brodski, J. Brodzicka, A. Brossa Gonzalo, D. Brundu, E. Buchanan, A. Buonaura, C. Burr, A. Bursche, J. Buytaert, W. Byczynski, S. Cadeddu, H. Cai, R. Calabrese, R. Calladine, M. Calvi, M. Calvo Gomez, A. Camboni, P. Campana, D. H. Campora Perez, L. Capriotti, A. Carbone, G. Carboni, R. Cardinale, A. Cardini, P. Carniti, L. Carson, K. Carvalho Akiba, G. Casse, L. Cassina, M. Cattaneo, G. Cavallero, R. Cenci, D. Chamont, M. G. Chapman, M. Charles, Ph. Charpentier, G. Chatzikonstantinidis, M. Chefdeville, V. Chekalina, C. Chen, S. Chen, S.-G. Chitic, V. Chobanova, M. Chrzaszcz, A. Chubykin, P. Ciambrone, X. Cid Vidal, G. Ciezarek, F. Cindolo, P. E. L. Clarke, M. Clemencic, H. V. Cliff, J. Closier, V. Coco, J. A. B. Coelho, J. Cogan, E. Cogneras, L. Cojocariu, P. Collins, T. Colombo, A. Comerma-Montells, A. Contu, G. Coombs, S. Coquereau, G. Corti, M. Corvo, C. M. Costa Sobral, B. Couturier, G. A. Cowan, D. C. Craik, A. Crocombe, M. Cruz Torres, R. Currie, C. D’Ambrosio, F. Da Cunha Marinho, C. L. Da Silva, E. Dall’Occo, J. Dalseno, A. Danilina, A. Davis, O. De Aguiar Francisco, K. De Bruyn, S. De Capua, M. De Cian, J. M. De Miranda, L. De Paula, M. De Serio, P. De Simone, C. T. Dean, D. Decamp, L. Del Buono, B. Delaney, H.-P. Dembinski, M. Demmer, A. Dendek, D. Derkach, O. Deschamps, F. Desse, F. Dettori, B. Dey, A. Di Canto, P. Di Nezza, S. Didenko, H. Dijkstra, F. Dordei, M. Dorigo, A. Dosil Suárez, L. Douglas, A. Dovbnya, K. Dreimanis, L. Dufour, G. Dujany, P. Durante, J. M. Durham, D. Dutta, R. Dzhelyadin, M. Dziewiecki, A. Dziurda, A. Dzyuba, S. Easo, U. Egede, V. Egorychev, S. Eidelman, S. Eisenhardt, U. Eitschberger, R. Ekelhof, L. Eklund, S. Ely, A. Ene, S. Escher, S. Esen, T. Evans, A. Falabella, N. Farley, S. Farry, D. Fazzini, L. Federici, P. Fernandez Declara, A. Fernandez Prieto, F. Ferrari, L. Ferreira Lopes, F. Ferreira Rodrigues, M. Ferro-Luzzi, S. Filippov, R. A. Fini, M. Fiorini, M. Firlej, C. Fitzpatrick, T. Fiutowski, F. Fleuret, M. Fontana, F. Fontanelli, R. Forty, V. Franco Lima, M. Frank, C. Frei, J. Fu, W. Funk, C. Färber, M. Féo, E. Gabriel, A. Gallas Torreira, D. Galli, S. Gallorini, S. Gambetta, Y. Gan, M. Gandelman, P. Gandini, Y. Gao, L. M. Garcia Martin, B. Garcia Plana, J. García Pardiñas, J. Garra Tico, L. Garrido, D. Gascon, C. Gaspar, L. Gavardi, G. Gazzoni, D. Gerick, E. Gersabeck, M. Gersabeck, T. Gershon, D. Gerstel, Ph. Ghez, V. Gibson, O. G. Girard, P. Gironella Gironell, L. Giubega, K. Gizdov, V. V. Gligorov, D. Golubkov, A. Golutvin, A. Gomes, I. V. Gorelov, C. Gotti, E. Govorkova, J. P. Grabowski, R. Graciani Diaz, L. A. Granado Cardoso, E. Graugés, E. Graverini, G. Graziani, A. Grecu, R. Greim, P. Griffith, L. Grillo, L. Gruber, B. R. Gruberg Cazon, O. Grünberg, C. Gu, E. Gushchin, A. Guth, Yu. Guz, T. Gys, C. Göbel, T. Hadavizadeh, C. Hadjivasiliou, G. Haefeli, C. Haen, S. C. Haines, B. Hamilton, X. Han, T. H. Hancock, S. Hansmann-Menzemer, N. Harnew, S. T. Harnew, T. Harrison, C. Hasse, M. Hatch, J. He, M. Hecker, K. Heinicke, A. Heister, K. Hennessy, L. Henry, E. van Herwijnen, J. Heuel, M. Heß, A. Hicheur, R. Hidalgo Charman, D. Hill, M. Hilton, P. H. Hopchev, J. Hu, W. Hu, W. Huang, Z. C. Huard, W. Hulsbergen, T. Humair, M. Hushchyn, D. Hutchcroft, D. Hynds, P. Ibis, M. Idzik, P. Ilten, A. Inyakin, K. Ivshin, R. Jacobsson, J. Jalocha, E. Jans, B. K. Jashal, A. Jawahery, F. Jiang, M. John, D. Johnson, C. R. Jones, C. Joram, B. Jost, N. Jurik, S. Kandybei, M. Karacson, J. M. Kariuki, S. Karodia, N. Kazeev, M. Kecke, F. Keizer, M. Kelsey, M. Kenzie, T. Ketel, E. Khairullin, B. Khanji, C. Khurewathanakul, K. E. Kim, T. Kirn, S. Klaver, K. Klimaszewski, T. Klimkovich, S. Koliiev, M. Kolpin, R. Kopecna, P. Koppenburg, I. Kostiuk, S. Kotriakhova, M. Kozeiha, L. Kravchuk, M. Kreps, F. Kress, P. Krokovny, W. Krupa, W. Krzemien, W. Kucewicz, M. Kucharczyk, V. Kudryavtsev, A. K. Kuonen, T. Kvaratskheliya, D. Lacarrere, G. Lafferty, A. Lai, D. Lancierini, G. Lanfranchi, C. Langenbruch, T. Latham, C. Lazzeroni, R. Le Gac, A. Leflat, J. Lefrançois, R. Lefèvre, F. Lemaitre, O. Leroy, T. Lesiak, B. Leverington, P.-R. Li, Y. Li, Z. Li, X. Liang, T. Likhomanenko, R. Lindner, F. Lionetto, V. Lisovskyi, G. Liu, X. Liu, D. Loh, A. Loi, I. Longstaff, J. H. Lopes, G. H. Lovell, D. Lucchesi, M. Lucio Martinez, A. Lupato, E. Luppi, O. Lupton, A. Lusiani, X. Lyu, F. Machefert, F. Maciuc, V. Macko, P. Mackowiak, S. Maddrell-Mander, O. Maev, P. C. Magalhães, K. Maguire, D. Maisuzenko, M. W. Majewski, S. Malde, B. Malecki, A. Malinin, T. Maltsev, G. Manca, G. Mancinelli, D. Marangotto, J. Maratas, J. F. Marchand, U. Marconi, C. Marin Benito, M. Marinangeli, P. Marino, J. Marks, P. J. Marshall, G. Martellotti, M. Martin, M. Martinelli, D. Martinez Santos, F. Martinez Vidal, A. Massafferri, M. Materok, R. Matev, A. Mathad, Z. Mathe, C. Matteuzzi, A. Mauri, E. Maurice, B. Maurin, A. Mazurov, M. McCann, A. McNab, R. McNulty, J. V. Mead, B. Meadows, C. Meaux, N. Meinert, D. Melnychuk, M. Merk, A. Merli, E. Michielin, D. A. Milanes, E. Millard, M.-N. Minard, L. Minzoni, D. S. Mitzel, A. Mogini, R. D. Moise, T. Mombächer, I. A. Monroy, S. Monteil, M. Morandin, G. Morello, M. J. Morello, O. Morgunova, J. Moron, A. B. Morris, R. Mountain, F. Muheim, M. Mulder, C. H. Murphy, D. Murray, A. Mödden, D. Müller, J. Müller, K. Müller, V. Müller, P. Naik, T. Nakada, R. Nandakumar, A. Nandi, T. Nanut, I. Nasteva, M. Needham, N. Neri, S. Neubert, N. Neufeld, M. Neuner, R. Newcombe, T. D. Nguyen, C. Nguyen-Mau, S. Nieswand, R. Niet, N. Nikitin, A. Nogay, N. S. Nolte, D. P. O’Hanlon, A. Oblakowska-Mucha, V. Obraztsov, S. Ogilvy, R. Oldeman, C. J. G. Onderwater, A. Ossowska, J. M. Otalora Goicochea, T. Ovsiannikova, P. Owen, A. Oyanguren, P. R. Pais, T. Pajero, A. Palano, M. Palutan, G. Panshin, A. Papanestis, M. Pappagallo, L. L. Pappalardo, W. Parker, C. Parkes, G. Passaleva, A. Pastore, M. Patel, C. Patrignani, A. Pearce, A. Pellegrino, G. Penso, M. Pepe Altarelli, S. Perazzini, D. Pereima, P. Perret, L. Pescatore, K. Petridis, A. Petrolini, A. Petrov, S. Petrucci, M. Petruzzo, B. Pietrzyk, G. Pietrzyk, M. Pikies, M. Pili, D. Pinci, J. Pinzino, F. Pisani, A. Piucci, V. Placinta, S. Playfer, J. Plews, M. Plo Casasus, F. Polci, M. Poli Lener, A. Poluektov, N. Polukhina, I. Polyakov, E. Polycarpo, G. J. Pomery, S. Ponce, A. Popov, D. Popov, S. Poslavskii, C. Potterat, E. Price, J. Prisciandaro, C. Prouve, V. Pugatch, A. Puig Navarro, H. Pullen, G. Punzi, W. Qian, J. Qin, R. Quagliani, B. Quintana, N. V. Raab, B. Rachwal, J. H. Rademacker, M. Rama, M. Ramos Pernas, M. S. Rangel, F. Ratnikov, G. Raven, M. Ravonel Salzgeber, M. Reboud, F. Redi, S. Reichert, A. C. dos Reis, F. Reiss, C. Remon Alepuz, Z. Ren, V. Renaudin, S. Ricciardi, S. Richards, K. Rinnert, P. Robbe, A. Robert, M. R. Robilotta, A. B. Rodrigues, E. Rodrigues, J. A. Rodriguez Lopez, M. Roehrken, S. Roiser, A. Rollings, V. Romanovskiy, A. Romero Vidal, M. Rotondo, M. S. Rudolph, T. Ruf, J. Ruiz Vidal, J. J. Saborido Silva, N. Sagidova, B. Saitta, V. Salustino Guimaraes, C. Sanchez Gras, C. Sanchez Mayordomo, B. Sanmartin Sedes, R. Santacesaria, C. Santamarina Rios, M. Santimaria, E. Santovetti, G. Sarpis, A. Sarti, C. Satriano, A. Satta, M. Saur, D. Savrina, S. Schael, M. Schellenberg, M. Schiller, H. Schindler, M. Schmelling, T. Schmelzer, B. Schmidt, O. Schneider, A. Schopper, H. F. Schreiner, M. Schubiger, M. H. Schune, R. Schwemmer, B. Sciascia, A. Sciubba, A. Semennikov, E. S. Sepulveda, A. Sergi, N. Serra, J. Serrano, L. Sestini, A. Seuthe, P. Seyfert, M. Shapkin, Y. Shcheglov, T. Shears, L. Shekhtman, V. Shevchenko, E. Shmanin, B. G. Siddi, R. Silva Coutinho, L. Silva de Oliveira, G. Simi, S. Simone, I. Skiba, N. Skidmore, T. Skwarnicki, M. W. Slater, J. G. Smeaton, E. Smith, I. T. Smith, M. Smith, M. Soares, l. Soares Lavra, M. D. Sokoloff, F. J. P. Soler, B. Souza De Paula, B. Spaan, E. Spadaro Norella, P. Spradlin, F. Stagni, M. Stahl, S. Stahl, P. Stefko, S. Stefkova, O. Steinkamp, S. Stemmle, O. Stenyakin, M. Stepanova, H. Stevens, A. Stocchi, S. Stone, B. Storaci, S. Stracka, M. E. Stramaglia, M. Straticiuc, U. Straumann, S. Strokov, J. Sun, L. Sun, K. Swientek, A. Szabelski, T. Szumlak, M. Szymanski, S. T’Jampens, Z. Tang, A. Tayduganov, T. Tekampe, G. Tellarini, F. Teubert, E. Thomas, J. van Tilburg, M. J. Tilley, V. Tisserand, M. Tobin, S. Tolk, L. Tomassetti, D. Tonelli, D. Y. Tou, R. Tourinho Jadallah Aoude, E. Tournefier, M. Traill, M. T. Tran, A. Trisovic, A. Tsaregorodtsev, G. Tuci, A. Tully, N. Tuning, A. Ukleja, A. Usachov, A. Ustyuzhanin, U. Uwer, A. Vagner, V. Vagnoni, A. Valassi, S. Valat, G. Valenti, R. Vazquez Gomez, P. Vazquez Regueiro, S. Vecchi, M. van Veghel, J. J. Velthuis, M. Veltri, G. Veneziano, A. Venkateswaran, M. Vernet, M. Veronesi, M. Vesterinen, J. V. Viana Barbosa, D. Vieira, M. Vieites Diaz, H. Viemann, X. Vilasis-Cardona, A. Vitkovskiy, M. Vitti, V. Volkov, A. Vollhardt, D. Vom Bruch, B. Voneki, A. Vorobyev, V. Vorobyev, N. Voropaev, J. A. de Vries, C. Vázquez Sierra, R. Waldi, J. Walsh, J. Wang, M. Wang, Y. Wang, Z. Wang, D. R. Ward, H. M. Wark, N. K. Watson, D. Websdale, A. Weiden, C. Weisser, M. Whitehead, J. Wicht, G. Wilkinson, M. Wilkinson, I. Williams, M. R. J. Williams, M. Williams, T. Williams, F. F. Wilson, M. Winn, W. Wislicki, M. Witek, G. Wormser, S. A. Wotton, K. Wyllie, D. Xiao, Y. Xie, A. Xu, M. Xu, Q. Xu, Z. Xu, Z. Yang, Y. Yao, L. E. Yeomans, H. Yin, J. Yu, X. Yuan, O. Yushchenko, K. A. Zarebski, M. Zavertyaev, D. Zhang, L. Zhang, W. C. Zhang, Y. Zhang, A. Zhelezov, Y. Zheng, X. Zhu, V. Zhukov, J. B. Zonneveld, and S. Zucchelli

Subjects
Charm physics, Hadron-Hadron scattering (experiments), Particle and resonance production, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract The resonant structure of the doubly Cabibbo-suppressed decay D +→K − K + K + is studied for the first time. The measurement is based on a sample of pp-collision data, collected at a centre-of-mass energy of 8 TeV with the LHCb detector and corresponding to an integrated luminosity of 2 fb−1. The amplitude analysis of this decay is performed with the isobar model and a phenomenological model based on an effective chiral Lagrangian. In both models the S-wave component in the K − K + system is dominant, with a small contribution of the ϕ(1020) meson and a negligible contribution from tensor resonances. The K + K − scattering amplitudes for the considered combinations of spin (0,1) and isospin (0,1) of the two-body system are obtained from the Dalitz plot fit with the phenomenological decay amplitude.

Published
2019
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3. NUCLEAR INTERACTIONS: THE CHIRAL PICTURE

Author

M. R. Robilotta

Subjects
Physics, Nuclear and High Energy Physics, Nuclear Theory, Scalar (mathematics), Form factor (quantum field theory), FOS: Physical sciences, General Physics and Astronomy, Astronomy and Astrophysics, Symmetry (physics), Nuclear Theory (nucl-th), Theoretical physics, Nuclear Experiment, Nucleon
Abstract

Chiral expansions of the two-pion exchange components of both two- and three-nucleon forces are reviewed and a discussion is made of the predicted pattern of hierarchies. The strength of the scalar-isoscalar central potential is found to be too large and to defy expectations from the symmetry. The causes of this effect can be understood by studying the nucleon scalar form factor., Talk given at CHIRAL 07 - Osaka - November 2007

Published
2008

4. σfields and chiral scalars in nuclear three-body potentials

Author

M. R. Robilotta and C. M. Maekawa

Subjects
Chiral anomaly, Physics, Nuclear and High Energy Physics, Theoretical physics, Chiral perturbation theory, Pion, Field (physics), Quantum mechanics, Nuclear Theory, Nuclear force, Invariant (mathematics), Nucleon, Chiral symmetry breaking
Abstract

The scalar-isoscalar field of an effective chiral Lagrangian transforms differently in either linear or non-linear frameworks: in the former case it is the counterpart of the pion whereas in the latter it is chiral invariant on its own. We compare the predictions from these two models for nucleon interactions and find results which are identical for two-body and rather different for three-body potentials. Some qualitative features of three-body interactions are discussed.

Published
1998

5. NNscattering: Chiral predictions for asymptotic observables

Author

M. R. Robilotta, C. A. Da Rocha, J. L. Ballot, Inst. de Physique Nucléaire, Universidade de São Paulo (USP), Box 351560, Universidade Estadual Paulista (Unesp), Institut de Physique Nucléaire d'Orsay (IPNO), 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, Nuclear and High Energy Physics, Nuclear Theory, [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th], 010308 nuclear & particles physics, Scattering, FOS: Physical sciences, Observable, Feynman graph, 01 natural sciences, Nuclear Theory (nucl-th), 0103 physical sciences, Nuclear Experiment, 010306 general physics, Mathematical physics
Abstract

We assume that the nuclear potential for distances larger than 2.5 fm is given just by the exchanges of one and two pions and, for the latter, we adopt a model based on chiral symmetry and subthreshold pion-nucleon amplitudes, which contains no free parameters. The predictions produced by this model for nucleon-nucleon observables are calculated and shown to agree well with both experiment and those due to phenomenological potentials., Comment: 16 pages, 12 PS figures included, to appear in Physical Review C

Published
1998

6. QCD vacuum: nuclear forces, nucleons, pions [ellipsis (horizontal)]

Author

M. R. Robilotta and Vito R. Vanin

Subjects
Quantum chromodynamics, Chiral anomaly, Physics, Particle physics, Chiral perturbation theory, High Energy Physics::Lattice, Nuclear Theory, High Energy Physics::Phenomenology, QCD vacuum, Pion, Quantum electrodynamics, Nambu–Jona-Lasinio model, Nuclear force, High Energy Physics::Experiment, Chiral symmetry breaking
Abstract

This contribution contains six sections, namely:1. from QCD to chiral perturbation theory ‐ QCD is widely accepted as the theory of strong interactions, but direct applications to low‐energy hadronic processes are difficult. In this regime, the light quarks u and d prevail, and one can employ a rigorously equivalent effective theory, known a chiral perturbation theory, based on hadronic degrees of freedom.2. strong vacuum and the pion ‐ Chiral symmetry is not exact in the real world. Nevertheless, the absence of of parity multiplets and the smallness of the pion mass suggest that it is a good approximate symmetry, realized in the Nambu‐Goldstone mode. Its ground state, the vacuum, is filled with a condensate, made of quark‐antiquark pairs. In sections 1–3, instances are presented of observables strongly influenced by the QCD vacuum.3. nuclear forces ‐ In the last few years, chiral perturbation theory has produced a very reliable picture of both two‐ and three‐nucleon forces. In particular, the important i...

Published
2011

7. D[sup +]→K[sup −]π[sup +]π[sup +]: three-body FSI

Author

P. C. Magalhães, M. R. Robilotta, Marina Nielsen, Fernando S. Navarra, and Mirian E. Bracco

Subjects
Nuclear physics, Quark, Pseudoscalar, Physics, Particle decay, Particle physics, Pion, Meson, Hadron, Elementary particle, Boson
Abstract

Even with the important advances of the last decade, charmed meson decays are still poorly understood theoretically. We do not understand, for example, why the kappa scalar resonance is responsible for 70% of the fit in the D+→K−π+π+ decay, as observed by the E791 (2002) experiment[1] and confirmed by different collaborations[2, 3]. The fact that quark c can neither be considered soft nor heavy prevents the direct use of known theoretical results in the description of D. This scenario indicates two big gaps in the knowledge of D+→π+π+K− decay. The first concerns the weak vertex, still not suitably treated in literature. The second is the three‐body final state interaction (FSI) of the pseudoscalar mesons, until now considered in the literature as a quasi two‐body interaction . This investigation aims at calculating the D+→π+π+K− decay considering 3 body FSI.

Published
2010

8. Nuclear interactions and the space-like structure of the pion

Author

M. R. Robilotta

Subjects
Coupling constant, Physics, Particle physics, Chiral perturbation theory, Nuclear Theory, Scalar (mathematics), Form factor (quantum field theory), FOS: Physical sciences, Nuclear Theory (nucl-th), Pion, Isospin, Goldstone boson, Nucleon, Nuclear Experiment
Abstract

Three instances are discussed in which results produced by chiral perturbation theory can be reliably pushed to high space-like values of transferred momenta: 1. nuclear interactions, 2. nucleon sigma-term and 3. space-like structure of the pion, Comment: 6th International Workshop on Chiral Dynamics, CD09, 6-10 July 2009, Bern, Switzerland

Published
2009
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9. Three-nucleon interactions: dynamics

Author

M. R. Robilotta, Hideyuki Sakai, Kimiko Sekiguchi, and Benjamin F. Gibson

Subjects
Physics, Chiral symmetry, Nuclear Theory, Dynamics (mechanics), FOS: Physical sciences, macromolecular substances, Three-body problem, Nuclear Theory (nucl-th), Theoretical physics, Pion, Nuclear force, sense organs, Nucleon, skin and connective tissue diseases, Nuclear theory
Abstract

A discussion is presented of the dynamics underlying three-body nuclear forces, with emphasis on changes which occurred over several decades., Comment: Talk given at the FM50 symposium, Tokyo, October 2007

Published
2008
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10. Unitarized amplitude for two coupled scalar resonances

Author

P. C. Magalhães, M. R. Robilotta, George Rupp, Eef van Beveren, Pedro Bicudo, Brigitte Hiller, and Frieder Kleefeld

Subjects
Quantum chromodynamics, Physics, Renormalization, Scattering amplitude, Elastic scattering, Amplitude, Scattering, Quantum electrodynamics, Quantum mechanics, High Energy Physics::Phenomenology, Scalar (mathematics), S-matrix
Abstract

This work is part of a more general description of final state interactions in the reaction D+→K−π+π+, which involve elastic meson‐meson scattering. The unitarization of a π+K− amplitude containing scalar resonances is studied by means of a chiral effective lagrangian. We show that the number of zeroes of the amplitude is the same as the number of resonances considered explicitly. A comparison is made, in the two‐resonance case, with alternative results in the literature used in the interpretation of experimental data.

Published
2008

11. Sigma term of the sigma: a preliminary study

Author

G. R. S. Zarnauskas, M. R. Robilotta, George Rupp, Eef van Beveren, Pedro Bicudo, Brigitte Hiller, and Frieder Kleefeld

Subjects
Quantum chromodynamics, Physics, symbols.namesake, Particle physics, Particle decay, Sigma model, symbols, Feynman diagram, Sigma, Configuration space, Resonance (particle physics), Term (time)
Abstract

We present an estimate for the sigma term of the sigma resonance using the linear sigma model in configuration space. Our calculation involves four diagrams and we have obtained stable results for three of them. The last one describes the sigma decay and is being studied at present.

Published
2008

12. Production amplitude for a single scalar resonance

Author

D. R. Boito, M. R. Robilotta, George Rupp, Eef van Beveren, Pedro Bicudo, Brigitte Hiller, and Frieder Kleefeld

Subjects
Pseudoscalar, Physics, Amplitude, Meson, High Energy Physics::Lattice, Spontaneous symmetry breaking, Quantum electrodynamics, High Energy Physics::Phenomenology, Nuclear Theory, Scalar (mathematics), Phase (waves), Resonance, Propagator
Abstract

We derive a simple expression for the production amplitude of two pseudoscalar mesons involving a single scalar resonance. This amplitude is determined by a combination of Watson's phase δ(s) and another phase ω(s), related to an unambiguous two‐meson propagator. With a lagrangian model, we study the σππ system.

Published
2008

13. Scalar resonances: scattering and production amplitudes

Author

Diogo Boito and M. R. Robilotta

Subjects
Physics, Nuclear and High Energy Physics, Scattering, Scalar (mathematics), Phase (waves), FOS: Physical sciences, Omega, Scattering amplitude, High Energy Physics - Phenomenology, Amplitude, High Energy Physics - Phenomenology (hep-ph), Simple (abstract algebra), Quantum mechanics, Quantum electrodynamics, Production (computer science)
Abstract

Scattering and production amplitudes involving scalar resonances are known, according to Watson's theorem, to share the same phase $\delta(s)$. We show that, at low energies, the production amplitude is fully determined by the combination of $\delta(s)$ with another phase $\omega(s)$, which describes intermediate two-meson propagation and is theoretically unambiguous. Our main result is a simple and almost model independent expression, which generalizes the usual $K$-matrix unitarization procedure and is suited to be used in analyses of production data involving scalar resonances., Comment: 10 pages, 4 figures. Minor changes, references added, version to appear in Phys. Rev. D

Published
2007

15. Hyperon scalar form factors

Author

C. C. Barros and M. R. Robilotta

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Scattering, High Energy Physics::Phenomenology, Nuclear Theory, Hyperon, Scalar (physics), FOS: Physical sciences, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), High Energy Physics::Experiment, Nuclear Experiment, Engineering (miscellaneous)
Abstract

We evaluate the long range part of the hyperon form factors and their contribution to elastic pion-hyperon scattering., 11 pages, 3 figures

Published
2002

17. Chiral Symmetry: Pion-Nucleon Interactions in Constituent Quark Models

Author

M. R. Robilotta and C. M. Maekawa

Subjects
Physics, Quark, Nuclear and High Energy Physics, Particle physics, High Energy Physics::Lattice, Quark model, High Energy Physics::Phenomenology, Nuclear Theory, Yukawa potential, Constituent quark, FOS: Physical sciences, Coupling (probability), High Energy Physics - Phenomenology, Pion, High Energy Physics - Phenomenology (hep-ph), Up quark, High Energy Physics::Experiment, Nucleon, Nuclear Experiment
Abstract

We study the interactions of an elementary pion with a nucleon made of constituent quarks and show that the enforcement of chiral symmetry requires the use of a two-body operator, whose form does not depend on the choice of the pion-quark coupling. The coordinate space NN effective potential in the pion exchange channel is given as a sum of terms involving two gradients, that operate on both the usual Yukawa function and the confining potential. We also consider an application to the case of quarks bound by a harmonic potential and show that corrections due to the symmetry are important., Comment: revtex style, 28 pages, 2 figures, use epsf.sty

Published
1996
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18. Two pion exchange nucleon-nucleon potential: The minimal chiral model

Author

M. R. Robilotta and C. A. da Rocha

Subjects
Physics, Chiral anomaly, Nuclear and High Energy Physics, Range (particle radiation), Particle physics, Component (thermodynamics), High Energy Physics::Lattice, Nuclear Theory, Chirality (electromagnetism), Nuclear physics, Pion, Chiral model, Configuration space, Nuclear Experiment, Nucleon
Abstract

We evaluate the two pion exchange contribution to the nucleon-nucleon potential in configuration space using a minimal chiral model containing only pions and nucleons. The scalar-isoscalar component of the interaction is relatively small, due to cancellations between large terms, and fails to reproduce the intermediate range attraction in the central channel. We show that these results do not depend on how chiral symmetry is implemented.

Published
1994

19. Pionic background for nucleon-nucleon observables

Author

M R Robilotta, J L Ballot, 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
Physics, Nuclear and High Energy Physics, Particle physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], 010308 nuclear & particles physics, Scattering, Nuclear Theory, Phase (waves), Observable, 01 natural sciences, 0103 physical sciences, Nuclear Experiment, 010306 general physics, Nucleon, Mixing (physics)
Abstract

We present a method that allows the unambiguous definition of the one-pion exchange contribution to nucleon-nucleon scattering observables and then use it to determine those waves where values of phase shifts and mixing parameters may be understood as sums of pionic and non-pionic dynamical effects. This helps the assessment of the explanatory power of the various existing phenomenological potentials and may eventually lead to ways of discriminating their effectiveness.

Published
1994

21. On the pion-deuteron scattering length

Author

M R Robilotta and Colin Wilkin

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Particle physics, Pion, Deuterium, Nuclear Theory, General Physics and Astronomy, Scattering length, Nuclear Experiment
Abstract

It is shown that a cancellation causes the contribution from certain exchange currents to the pion+deuteron scattering length to be much smaller than previously estimated.

Published
1978

22. On the Construction of Three-Nucleon Potentials

Author

M. R. Robilotta

Subjects
Chiral symmetry, Theoretical physics, Work (electrical), Computer science, Perspective (graphical), Form factor (quantum field theory), Nucleon
Abstract

The research programme for constructing three nucleon potentials is discussed and an attempt is made to insert recent developments into a broad chronological perspective. My aim is both to put into evidence the sometimes subtle differences among the various approaches and to demarcate areas that demand further work.

Published
1987

23. Forces on a current-carrying wire in a magnetic field: the macro–micro connection.

Author

R Karam, F B Kneubil, and M R Robilotta

Subjects
MAGNETIC field measurements, ELECTROMAGNETISM, PHYSICS education, MAGNITUDE estimation, ELECTRONS, MATHEMATICAL models
Abstract

The classic problem of determining the force on a current-carrying wire in a magnetic field is critically analysed. A common explanation found in many introductory textbooks is to represent the force on the wire as the sum of the forces on charge carriers. In this approach neither the nature of the forces involved nor their application points are fully discussed. In this paper we provide an alternative microscopic explanation that is suitable for introductory electromagnetism courses at university level. By considering the wire as a superposition of a positive and a negative cylindrical charge distributions, we show that the electrons are subject to both magnetic and electric forces, whereas the ionic lattice of the metal is dragged by an electric force. Furthermore, an analysis of the orders of magnitude involved in the problem gives counterintuitive results with valuable educational potential. We argue that this approach allows one to discuss different aspects of the physical knowledge, which are relevant in physics education. [ABSTRACT FROM AUTHOR]

Published
2017
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