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2. Observational Constraints on the Dark Energy Equation of State

Author

Ribeiro, Williams J. M.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Late-time cosmic acceleration is one of the most interesting unsolved puzzles in modern cosmology. The explanation most accepted nowadays, dark energy, raises questions about its own nature, e.g. what exactly is dark energy, and implications to the observations, e.g. how to handle fine tuning problem and coincidence problem. Hence, dark energy evolution through cosmic history, together with its equation of state, are subjects of research in many current experiments. In this dissertation, using Markov Chain Monte Carlo sampling, we try to constrain the evolution of the dark energy equation of state in a nearly model-independent approach by combining different datasets coming from observations of baryon acoustic oscillations, cosmic chronometers, cosmic microwave background anisotropies and type Ia supernovae. We found no strong evidence that could indicate deviations from $\Lambda$CDM model, which is the standard model in cosmology accepted today., Comment: 112 pages, 31 figures, Master's degree dissertation (University of S\~ao Paulo)

Published
2019

3. Higgs Physics at the HL-LHC and HE-LHC

Author

Cepeda, M., Gori, S., Ilten, P., Kado, M., Riva, F., Khalek, R. Abdul, Aboubrahim, A., Alimena, J., Alioli, S., Alves, A., Asawatangtrakuldee, C., Azatov, A., Azzi, P., Bailey, S., Banerjee, S., Barberio, E. L., Barducci, D., Barone, G., Bauer, M., Bautista, C., Bechtle, P., Becker, K., Benaglia, A., Bengala, M., Berger, N., Bertella, C., Bethani, A., Betti, A., Biekotter, A., Bishara, F., Bloch, D., Bokan, P., Bondu, O., Bonvini, M., Borgonovi, L., Borsato, M., Boselli, S., Braibant-Giacomelli, S., Buchalla, G., Cadamuro, L., Caillol, C., Calandri, A., Tazon, A. Calderon, Campbell, J. M., Caola, F., Capozi, M., Carena, M., Calame, C. M. Carloni, Carmona, A., Carquin, E., De Oliveira, A. Carvalho Antunes, Hernandez, A. Castaneda, Cata, O., Celis, A., Cerri, A., Cerutti, F., Chahal, G. S., Chakraborty, A., Chaudhary, G., Chen, X., Chisholm, A. S., Contino, R., Costa, A. J., Covarelli, R., Craig, N., Curtin, D., D'Eramo, L., Dang, N. P., Das, P., Dawson, S., Francisco, O. A. De Aguiar, de Blas, J., De Curtis, S., De Filippis, N., De la Torre, H., de Lima, L., De Wit, A., Delaere, C., Delcourt, M., Delmastro, M., Demers, S., Dev, N., Di Nardo, R., Di Vita, S., Dildick, S., Prado, L. A. F. do, Donadelli, M., Du, D., Durieux, G., Dührssen, M., Eberhardt, O., Morabit, K. El, Elias-Miro, J., Ellis, J., Englert, C., Essig, R., Falke, S., Farina, M., Ferrari, A., Ferroglia, A., Fiolhais, M. C. N., Flechl, M., Folgueras, S., Fontanesi, E., Francavilla, P., Franceschini, R., Frederix, R., Frixione, S., Gómez-Ceballos, G., Gabrielli, A., Gadatsch, S., Gallinaro, M., Gandrakota, A., Gao, J., Walls, F. M. Garay, Gehrmann, T., Gershtein, Y., Ghosh, T., Gilbert, A., Glein, R., Glover, E. W. N., Gomez-Ambrosio, R., Gonçalo, R., Gonçalves, D., Gorbahn, M., Gouveia, E., Gouzevitch, M., Govoni, P., Grazzini, M., Greenberg, B., Grimm, K., Gritsan, A. V., Grohsjean, A., Grojean, C., Gu, J., Gugel, R., Gupta, R. S., Gwilliam, C. B., Höche, S., Haacke, M., Haddad, Y., Haisch, U., Hamity, G. N., Han, T., Harland-Lang, L. A., Harnik, R., Heinemeyer, S., Heinrich, G., Henning, B., Hirschi, V., Hoepfner, K., Hogan, J. M., Homiller, S., Huang, Y., Huss, A., Jézéquel, S., Jain, Sa., Jones, S. P., Köneke, K., Kalinowski, J., Kamenik, J. F., Kaplan, M., Karlberg, A., Kaur, M., Keicher, P., Kerner, M., Khanov, A., Kieseler, J., Kim, J. H., Kim, M., Klijnsma, T., Kling, F., Klute, M., Komaragiri, J. R., Kong, K., Kozaczuk, J., Kozow, P, Krause, C., Lai, S., Langford, J., Le, B., Lechner, L., Leight, W. A., Leney, K. J. C., Lenz, T., Li, C-Q., Li, H., Li, Q., Liebler, S., Lindert, J., Liu, D., Liu, J., Liu, Y., Liu, Z., Lombardo, D., Long, A., Long, K., Low, I., Luisoni, G., Ma, L. L., Magnan, A. -M., Majumder, D., Malinauskas, A., Maltoni, F., Mangano, M. L., Marchiori, G., Marini, A. C., Martin, A., Marzani, S., Massironi, A., Matchev, K. T., Matheus, R. D., Mazumdar, K., Mazzitelli, J., Mcdougall, A. E., Meade, P., Meridiani, P., Meyer, A. B., Michielin, E., Milenovic, P., Milosevic, V., Mimasu, K., Mistlberger, B., Mlynarikova, M., Mondragon, M., Monni, P. F., Montagna, G., Monti, F., Llacer, M. Moreno, Mueck, A., Muiño, P. C., Murphy, C., Murray, W. J., Musella, P., Narain, M., Garcia, R. F. Naranjo, Nath, P., Neubert, M., Nicrosini, O., Nikolopoulos, K., Nisati, A., No, J. M., Ojeda, M. L., Pino, S. A. Olivares, Onofre, A., Ortona, G., Griso, S. Pagan, Pagani, D., Cortezon, E. Palencia, Palmer, C., Pandini, C., Panico, G., Panwar, L., Pappadopulo, D., Park, M., Patel, R., Paucar-Velasquez, F., Pedro, K., Pernie, L., Perrozzi, L., Petersen, B. A., Petit, E., Petrucciani, G., Piacquadio, G., Piccinini, F., Pieri, M., Plehn, T., Pokorski, S., Pomarol, A., Ponton, E., Pozzorini, S., Prestel, S., Prokofiev, K., Ramsey-Musolf, M., Re, E., Readioff, N. P., Redigolo, D., Reina, L., Reynolds, E., Riembau, M., Rikkert, F., Robens, T., Roentsch, R., Rojo, J., Rompotis, N., Rorie, J., Rosiek, J., Roskes, J., Ruderman, J. T., Sahoo, N., Saito, S., Salerno, R., De Bruin, P. H. Sales, Salvucci, A., Sandeep, K., Santiago, J., Santo, R., Sanz, V., Sarica, U., Savin, A., Savoy-Navarro, A., Sawant, S., Schaffer, A. C., Schlaffer, M., Schmidt, A., Schneider, B., Schoefbeck, R., Schröder, M., Scodeggio, M., Scott, E., Scyboz, L., Selvaggi, M., Sestini, L., Shao, H. -S., Shivaji, A., Silvestrini, L., Simon, L., Sinha, K., Soreq, Y., Spannowsky, M., Spira, M., Spitzbart, D., Stamou, E., Stark, J., Stefaniak, T., Stieger, B., Strong, G., Szleper, M., Tackmann, K., Takeuchi, M., Taroni, S., Testa, M., Thamm, A., Theeuwes, V., Thomsen, L. A., Tkaczyk, S., Torre, R., Tramontano, F., Ulmer, K. A., Vantalon, T., Vecchi, L., Vega-Morales, R., Venturini, E., Verducci, M., Vernieri, C., Vickey, T., Marono, M. Vidal, Vischia, P., Vryonidou, E., Wagner, P., Walbrecht, V. M., Wang, L. -T., Wardle, N., Wardrope, D. R., Weiglein, G., Wertz, S., Wielers, M., Williams, J. M., Wolf, R., Wulzer, A., Xiao, M., Yang, H. T., Yazgan, E., Yin, Z., You, T., Yu, F., Zanderighi, G., Zanzi, D., Zaro, M., Zenz, S. C., Zerwas, D., Zgubič, M., Zhang, J., Zhang, L., Zhang, W., Zhao, X., and Zhong, Y. -M.

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Experiment
Abstract

The discovery of the Higgs boson in 2012, by the ATLAS and CMS experiments, was a success achieved with only a percent of the entire dataset foreseen for the LHC. It opened a landscape of possibilities in the study of Higgs boson properties, Electroweak Symmetry breaking and the Standard Model in general, as well as new avenues in probing new physics beyond the Standard Model. Six years after the discovery, with a conspicuously larger dataset collected during LHC Run 2 at a 13 TeV centre-of-mass energy, the theory and experimental particle physics communities have started a meticulous exploration of the potential for precision measurements of its properties. This includes studies of Higgs boson production and decays processes, the search for rare decays and production modes, high energy observables, and searches for an extended electroweak symmetry breaking sector. This report summarises the potential reach and opportunities in Higgs physics during the High Luminosity phase of the LHC, with an expected dataset of pp collisions at 14 TeV, corresponding to an integrated luminosity of 3 ab$^{-1}$. These studies are performed in light of the most recent analyses from LHC collaborations and the latest theoretical developments. The potential of an LHC upgrade, colliding protons at a centre-of-mass energy of 27 TeV and producing a dataset corresponding to an integrated luminosity of 15 ab$^{-1}$, is also discussed., Comment: Report from Working Group 2 on the Physics of the HL-LHC, and Perspectives at the HE-LHC, 364 pages

Published
2019

4. Beyond the Standard Model Physics at the HL-LHC and HE-LHC

Author

Vidal, X. Cid, D'Onofrio, M., Fox, P. J., Torre, R., Ulmer, K. A., Aboubrahim, A., Albert, A., Alimena, J., Allanach, B. C., Alpigiani, C., Altakach, M., Amoroso, S., Anders, J. K., Araz, J. Y., Arbey, A., Azzi, P., Babounikau, I., Baer, H., Baker, M. J., Barducci, D., Barger, V., Baron, O., Navarro, L. Barranco, Battaglia, M., Bay, A., Bhatia, D., Biswas, S., Bloch, D., Bogavac, D., Borschensky, C., Bugge, M. K., Buttazzo, D., Cacciapaglia, G., Cadamuro, L., Calandri, A., Camargo, D. A., Canepa, A., Carminati, L., Carrá, S., Montoya, C. A. Carrillo, De Oliveira, A. Carvalho Antunes, Castillo, F. L., Cavaliere, V., Cavalli, D., Cecchi, C., Celis, A., Cerri, A., Chahal, G. S., Chakraborty, A., Chekanov, S. V., Cheng, H. J., Childers, J. T., Cirelli, M., Colegrove, O., Corcella, G., Corradi, M., Costa, M. J., Covarelli, R., Dang, N. P., Deandrea, A., De Curtis, S., De la Torre, H., Rose, L. Delle, Del Re, D., Demela, A., Demers, S., Dermisek, R., De Santo, A., Deshpande, K., Dey, B., Donini, J., Duncan, A. K., Dutta, V., Escobar, C., Fanó, L., Ferretti, G., Fiaschi, J., Fischer, O., Flacke, T., Frangipane, E. D., Frank, M., Frattari, G., Frizzell, D., Fuchs, E., Fuks, B., Gabrielli, E., Gainer, J., Gao, Y., Navarro, J. E. García, Genest, M. H., Giagu, S., Giudice, G. F., Goh, J., Gouzevitch, M., Govoni, P., Greljo, A., Grohsjean, A., Gurrola, A., Gustavino, G., Guyot, C., Gwilliam, C. B., Ha, S., Haisch, U., Haller, J., Han, T., Hayden, D., Heikinheimo, M., Heintz, U., Helsens, C., Hoepfner, K., Hogan, J. M., Huitu, K., Ilten, P., Ippolito, V., Ismail, A., Iyer, A. M., Jain, Sa., Jamin, D. O., Jeanty, L., Jezo, T., Johns, W., Kalogeropoulos, A., Karancsi, J., Kats, Y., Keller, H., Khanov, A., Kieseler, J., Kim, B., Kim, M. S., Kim, Y. G., Klasen, M., Klimek, M. D., Kogler, R., Komaragiri, J. R., Krämer, M., Kubota, S., Kulesza, A. K., Kulkarni, S., Lari, T., Ledovskoy, A., Lee, G. R., Lee, L., Lee, S. W., Leonardi, R., Les, R., Lewis, I. M., Li, Q., Li, T., Lim, I. T., Lim, S. H., Lin, K., Liu, Z., Long, K., Low, M., Lunghi, E., Madaffari, D., Mahmoudi, F., Majumder, D., Malvezzi, S., Mangano, M. L., Manoni, E., Marcano, X., Mariotti, A., Marjanovic, M., Marlow, D., Camalich, J. Martin, Cuevas, P. Matorras, McCullough, M., McDonald, E. F., Guisao, J. Mejia, Mele, B., Meloni, F., Melzer-Pellmann, I. -A., Merlassino, C., Meyer, A. B., Michielin, E., Miller, A. J., Mittnacht, L., Mondal, S., Moretti, S., Mukhopadhyay, S., Nachman, B. P., Nam, K., Narain, M., Nardecchia, M., Nath, P., Navarro-González, J., Nisati, A., Nitta, T., Noel, D. L., Nojiri, M. M., Ochoa-Ricoux, J. P., Oide, H., Ojeda, M. L., Griso, S. Pagan, Cortezon, E. Palencia, Panella, O., Pani, P., Panizzi, L., Panwar, L., Park, C. B., Pazzini, J., Pedro, K., Perego, M. M., Perrozzi, L., Petersen, B. A., Pierce, A., Polesello, G., Policicchio, A., Potter, C. J., Pralavorio, P., Presilla, M., Proudfoot, J., Queiroz, F. S., Ramirez-Sanchez, G., Redigolo, D., Reimers, A., Resconi, S., Rimoldi, M., Vergara, J. C. Rivera, Rizzo, T., Rogan, C., Romeo, F., Rosten, R., Ruiz, R., Ruiz-Alvarez, J., Iglesias, J. A. Sabater, Samani, B. Safarzadeh, Sagir, S., Saito, M., Saito, S., Sala, F., Salazar, C., Savin, A., Sawada, R., Sawant, S., Schienbein, I., Schlaffer, M., Schneider, B., Schuler, S. C., Sebastiani, C. D., Sekmen, S., Selvaggi, M., Sengupta, D., Serce, H., Serodio, H., Sestini, L., Shakya, B., Haghi, B. Shams Es, Sheldon, P., Shin, S., Simonetto, F., Soffi, L., Spannowsky, M., Stupak, J., Sullivan, M. J., Sunder, M., Takahashi, Y., Tata, X., Teagle, H., Terashi, K., Tesi, A., Thamm, A., Tobioka, K., Tornambe, P., Trovato, F., Tsiakkouri, D., Ungaro, F. C., Urbano, A., Usai, E., Vanegas, N., Vaslin, L., Sierra, C. Vázquez, Vivarelli, I., Milosavljevic, M. Vranjes, Waltari, H., Wang, R., Wang, X., Weber, M. S., Weiland, C., Wielers, M., Williams, J. M., Willocq, S., Xu, D., Yagyu, K., Yazgan, E., Ye, R., Yoo, H. D., You, T., Yu, F., Della Porta, G. Zevi, Zhang, W., Zhu, C., Zhuang, X., Zobec, J., Zupan, J., and Zurita, J.

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Experiment
Abstract

This is the third out of five chapters of the final report [1] of the Workshop on Physics at HL-LHC, and perspectives on HE-LHC [2]. It is devoted to the study of the potential, in the search for Beyond the Standard Model (BSM) physics, of the High Luminosity (HL) phase of the LHC, defined as $3~\mathrm{ab}^{-1}$ of data taken at a centre-of-mass energy of $14~\mathrm{TeV}$, and of a possible future upgrade, the High Energy (HE) LHC, defined as $15~\mathrm{ab}^{-1}$ of data at a centre-of-mass energy of $27~\mathrm{TeV}$. We consider a large variety of new physics models, both in a simplified model fashion and in a more model-dependent one. A long list of contributions from the theory and experimental (ATLAS, CMS, LHCb) communities have been collected and merged together to give a complete, wide, and consistent view of future prospects for BSM physics at the considered colliders. On top of the usual standard candles, such as supersymmetric simplified models and resonances, considered for the evaluation of future collider potentials, this report contains results on dark matter and dark sectors, long lived particles, leptoquarks, sterile neutrinos, axion-like particles, heavy scalars, vector-like quarks, and more. Particular attention is placed, especially in the study of the HL-LHC prospects, to the detector upgrades, the assessment of the future systematic uncertainties, and new experimental techniques. The general conclusion is that the HL-LHC, on top of allowing to extend the present LHC mass and coupling reach by $20-50\%$ on most new physics scenarios, will also be able to constrain, and potentially discover, new physics that is presently unconstrained. Moreover, compared to the HL-LHC, the reach in most observables will generally more than double at the HE-LHC, which may represent a good candidate future facility for a final test of TeV-scale new physics., Comment: Report from Working Group 3 on the Physics of the HL-LHC, and Perspectives at the HE-LHC; v2: final version updated with the latest contributions and summaries; 239 pages + refs; v3: typos and character misprint in Fig. 7.2 fixed; v4: added one missing author

Published
2018

5. Opportunities in Flavour Physics at the HL-LHC and HE-LHC

Author

Cerri, A., Gligorov, V. V., Malvezzi, S., Camalich, J. Martin, Zupan, J., Akar, S., Alimena, J., Allanach, B. C., Altmannshofer, W., Anderlini, L., Archilli, F., Azzi, P., Banerjee, S., Barter, W., Barton, A. E., Bauer, M., Belyaev, I., Benson, S., Bettler, M., Bhattacharya, R., Bifani, S., Birnkraut, A., Bishara, F., Blake, T., Blusk, S., Boos, E., Borsato, M., Bozzi, C., Bragagnolo, A., Brod, J., Brodzicka, J., Buras, A. J., Cadamuro, L., Carbone, A., Carena, M., Carli, I., Carmona, A., Cavallo, F. R., Celis, A., Cepeda, M., Chahal, G. S., Chala, M., Charles, J., Charles, M., Chen, K. F., Chobanova, V., Chrzaszcz, M., Ciezarek, G., Cirigliano, V., Ciuchini, M., Cliff, H., Cogan, J., Colangelo, G., Contu, A., Covarelli, R., Cowan, G., Crivellin, A., D'Ambrosio, G., D'Onofrio, M., Dang, N. P., Davis, A., Francisco, O. A. De Aguiar, De Bruyn, K., De Sanctis, U., De la Torre, H., Dekens, W., Deliot, F., Della Morte, M., Demers, S., Derkach, D., Deschamps, O., Descotes-Genon, S., Dettori, F., Di Canto, A., Dinardo, M., Dini, P., Dordei, F., Dorigo, M., Reis, A. dos, Dudko, L., Dufour, L., Durieux, G., Dutta, S., Dziurda, A., Eitschberger, U., Esposito, A., Estevez, M., Fajfer, S., Falkowski, A., Faroughy, D. A., Fedi, G., Fiorendi, S., Fiori, F., Fitzpatrick, C., Fleischer, R., Fontana, M., Fox, P. J., Freytsis, M., Gámiz, E., Gabriel, E., Gambino, P., Pardiñas, J. García, Geng, L. S., Gersabeck, E., Gersabeck, M., Gershon, T., Gilbert, A., Gonzalez-Alonso, M., Govoni, P., Graziani, G., Greljo, A., Grillo, L., Grinstein, B., Grohsjean, A., Grossman, Y., Guadagnoli, D., Guo, F. -K., Guzzi, L., Haller, J., Hamilton, B., Han, T., Harnik, R., Hill, D., Hiller, G., Hoepfner, K., Hogan, J. M., Hurth, T., Igonkina, O., Ilten, P., Isidori, G., Jain, Sa., John, M., Johnson, D., Jung, M., Jurik, N., Jäger, S., Kado, M., Kagan, A. L., Kamenik, J. F., Karliner, M., Kenzie, M., Khanji, B., Kieseler, J., Kitahara, T., Klijnsma, T., Knecht, M., Košnik, N., Kogler, R., Koppenburg, P., Korytov, A., Kreps, M., Langenbruch, C., Langenegger, U., Latham, T., Lebed, R. F., Lenz, A. J., Leonardo, N., Leroy, O., Li, Q., Li, T., Ligabue, F., Ligeti, Z., Long, K., Lunghi, E., Mahmoudi, F., Mancinelli, G., Mandrik, P., Mannel, T., Marcano, X., Marchand, J. F., Santos, D. Martínez, Martin, A., Martinelli, M., Vidal, F. Martinez, Marzocca, D., Matias, J., Cuevas, P. Matorras, Matsedonskyi, O., Mauri, A., Mazumdar, K., Merk, M., Meyer, A. B., Michielin, E., Mitselmakher, G., Mittnacht, L., Monteil, S., Morello, M. J., Morgenstern, M., Narain, M., Nardecchia, M., Needham, M., Neri, N., Neubert, M., Neubert, S., Nierste, U., Nieves, J., Nir, Y., Nisati, A., O'Hanlon, D. P., Oset, E., Owen, P., Ozcelik, O., Griso, S. Pagan, Cortezon, E. Palencia, Palla, F., Palutan, M., Pappagallo, M., Parkes, C., Pascoli, S., Passaleva, G., Passemar, E., Patel, M., Pearce, A., Pedro, K., Perazzini, S., Perfilov, M., Perrozzi, L., Pescatore, L., Petersen, B. A., Petrov, A. A., Pich, A., Pilloni, A., Polci, F., Polosa, A. D., Prelovsek, S., Navarro, A. Puig, Punzi, G., Rademacker, J., Rama, M., Reboud, M., Reimers, A., Reznicek, P., Robinson, D. J., Rosner, J. L., Ruiz, R., Saito, S., Sarkar, S., Savin, A., Sawant, S., Schacht, S., Schlaffer, M., Schmidt, A., Schneider, B., Schopper, A., Schune, M. H., Segovia, J., Selvaggi, M., Serra, N., Servant, G., Sestini, L., Shih, D., Coutinho, R. Silva, Silvestrini, L., Skovpen, K., Skwarnicki, T., Smizanska, M., Soni, A., Soreq, Y., Spannowsky, M., Spradlin, P., Stamou, E., Stone, S., Stracka, S., Straub, D. M., Szczepaniak, A. P, T'Jampens, S., Takahashi, Y., Teubert, F., Thomas, E., Tisserand, V., Torre, R., Tresoldi, F., Tsiakkouri, D., Turchikhin, S., Ulmer, K. A., Vagnoni, V., van Dyk, D., van Tilburg, J., Vecchi, S., Venditti, R., Vesterinen, M., Virto, J., Volkov, P., Vorotnikov, G., Vryonidou, E., Walder, J., Walkowiak, W., Wang, J., Wang, W., Weiland, C., Whitehead, M., Wilkinson, G., Williams, J. M., Williams, M. R. J., Wilson, F., Xie, Y., Yang, Z., Yazgan, E., You, T., Yu, F., Zhang, C., Zhang, L., and Zhang, W.

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Experiment
Abstract

Motivated by the success of the flavour physics programme carried out over the last decade at the Large Hadron Collider (LHC), we characterize in detail the physics potential of its High-Luminosity and High-Energy upgrades in this domain of physics. We document the extraordinary breadth of the HL/HE-LHC programme enabled by a putative Upgrade II of the dedicated flavour physics experiment LHCb and the evolution of the established flavour physics role of the ATLAS and CMS general purpose experiments. We connect the dedicated flavour physics programme to studies of the top quark, Higgs boson, and direct high-$p_T$ searches for new particles and force carriers. We discuss the complementarity of their discovery potential for physics beyond the Standard Model, affirming the necessity to fully exploit the LHC's flavour physics potential throughout its upgrade eras., Comment: Report from Working Group 4 on the Physics of the HL-LHC, and Perspectives at the HE-LHC, 292 pages

Published
2018

6. Projectile motion: the 'coming and going' phenomenon

Author

Ribeiro, Williams J. M. and de Sousa, J. Ricardo

Subjects
Physics - Classical Physics
Abstract

An interesting phenomenon that occurs in projectile motion, the "coming and going", is analyzed considering linear air resistance force. By performing both approximate and numerical analysis, it is showed how a determined critical angle and an interesting geometrical property of projectiles can change due to variation on the linear air resistance coefficient.

Published
2018
Full Text
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7. Projectile Motion: The 'Coming and Going' Phenomenon

Author

Ribeiro, Williams J. M. and de Sousa, J. Ricardo

Abstract

During elementary physics courses, many examples in mechanics are studied without considering air resistance effects. We can mention, for example, projectile motion and free fall, among many others. Only brief studies of such systems in classical mechanics courses consider linear air resistance (F[subscript drag] [is proportional to] v), which is the simplest model to account for the drag effect by modeling objects moving in viscous media with small velocities (more precisely, small Reynolds number). Quadratic air resistance (F[subscript drag] [is proportional to] v[superscript 2]), which applies for objects moving in resistive media with high velocities (high Reynolds number), is hardly mentioned, but it can be found in many papers. However, in nature air resistance plays a big role in the motion of bodies and so it must be included when studying any kind of phenomena related to mechanics.

Published
2021
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8. A Randomized Control Trial Evaluating the Effectiveness of Computer Assisted Instruction in Numeracy on Math Outcomes for Monolingual English Speaking Kindergartners from Title 1 Schools

Author

Society for Research on Educational Effectiveness (SREE), Foster, M. E., Anthony, J. L., Clements, D. H., Sarama, J., and Williams, J. M.

Abstract

Children from low-income and ethnic minority backgrounds have demonstrated substantially lower levels of math achievement than their middle class majority peers for decades. The present study addressed two research questions: (1) when used as a supplement to typical classroom instruction and in isolation from the larger curriculum, does Building Blocks Software lead to improvements in math achievement as measured by proximal and distal measures of mathematics?; and (2) are the impacts of supplemental use of Building Blocks Software specific to math achievement? Nine Title 1 schools drawn from a large urban school district in Texas that primarily served students from low-income and ethnic minority backgrounds participated in this study. Forty kindergarten classrooms, all with full-day programming, participated. The sample consisted of 243 monolingual English speaking children (52% female). Most of these children represented ethnic minorities: 63% were African American, 30% Hispanic/Latino, 4% mixed ethnicity, 2% Caucasian, and 1% other. At the study's onset, the sample's scores on norm-referenced standardized tests of verbal ability (M = 84; SD = 14) and nonverbal ability (M = 77, SD = 11) were low average and below average, respectively, indicating risk for poor academic outcomes. Participants were randomized to receive computer assisted instruction with "Building Blocks Software" or "Earobics Step 1", a literacy software program. Randomized control trial; participants were randomized with equal probability from within classroom to one of the two experimental conditions. Children's numeracy skills were assessed with the "Research Based Early Math Assessment," a measure proximal to the Building Blocks Software at the beginning (i.e., pretest) and at the end (i.e., posttest) of children's kindergarten year. At posttest, the Applied Problems subtest from the "Woodcock-Johnson III Tests of Achievement," a distal measure of broad math achievement, was administered. To examine treatment specificity, vocabulary was assessed with the "Expressive One Word Picture Vocabulary Test" at pretest and posttest. Significant benefits for posttest math scores, but not vocabulary scores, were seen for children in the "Building Blocks Software" condition. For numeracy scores at posttest, there was a main effect for group, F(1, 178) = 8.08, p < 0.01, after accounting for numeracy scores from pretest and classroom nesting. The "Building Blocks Software" group outperformed the comparison group, with a difference in least squared means of 1.85 raw score units. This study demonstrated that a relatively low intensity, supplemental implementation of "Building Blocks Software" throughout most of children's kindergarten school year led to reliable improvements in math achievement.

Published
2016

9. Operation of graphene quantum Hall resistance standard in a cryogen-free table-top system

Author

Janssen, T. J. B. M., Rozhko, S., Antonov, I., Tzalenchuk, A., Williams, J. M., Melhem, Z., He, H., Lara-Avila, S., Kubatkin, S., and Yakimova, R.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

We demonstrate quantum Hall resistance measurements with metrological accuracy in a small cryogen-free system operating at a temperature of around 3.8K and magnetic fields below 5T. Operating this system requires little experimental knowledge or laboratory infrastructure, thereby greatly advancing the proliferation of primary quantum standards for precision electrical metrology. This significant advance in technology has come about as a result of the unique properties of epitaxial graphene on SiC., Comment: 15 pages, 9 figures

Published
2015
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11. Precision comparison of the quantum Hall effect in graphene and gallium arsenide

Author

Janssen, T. J. B. M., Williams, J. M., Fletcher, N. E., Goebel, R., Tzalenchuk, A., Yakimova, R., Lara-Avila, S., Kubatkin, S., and Fal'ko, V. I.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

The half-integer quantum Hall effect in epitaxial graphene is compared with high precision to the well known integer effect in a GaAs/AlGaAs heterostructure. We find no difference between the quantised resistance values within the relative standard uncertainty of our measurement of $8.7\times 10^{-11}$. The result places new tighter limits on any possible correction terms to the simple relation $R_{\rm K}=h/e^2$, and also demonstrates that epitaxial graphene samples are suitable for application as electrical resistance standards of the highest metrological quality. We discuss the characterisation of the graphene sample used in this experiment and present the details of the cryogenic current comparator bridge and associated uncertainty budget.

Published
2012
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12. Graphene, universality of the quantum Hall effect and redefinition of the SI system

Author

Janssen, T. J. B. M., Fletcher, N. E., Goebel, R., Williams, J. M., Tzalenchuk, A., Yakimova, R., Kubatkin, S., Lara-Avila, S., and Falko, V. I.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

The Syst\`eme Internationale d'unit\'es (SI system) is about to undergo its biggest change in half a century by redefining the units for mass and current in terms of the fundamental constants h and e, respectively. This change crucially relies on the exactness of the relationships which link these constants to measurable quantities. Here we directly compare the integer quantum Hall effect in epitaxial graphene with that in GaAs/AlGaAs heterostructures. We find no difference of the quantized resistance value within the relative standard uncertainty of our measurement of 8.6\times10-11, being the most stringent test of the universality of the quantum Hall effect in terms of material independence.

Published
2011
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13. Spin resonance strengths due to rf solenoids and dipoles for stored deuteron beams

Author

Leonova, M. A., Chao, A. W., Courant, E. D., Krisch, A. D., Morozov, V. S., Raymond, R. S., Sivers, D. W., Williams, J. M., Wong, V. K., Garishvili, A., Gebel, R., Lehrach, A., Lorentz, B., Maier, R., Prasuhn, D., Stockhorst, H., Welsch, D., Hinterberger, F., Ulbrich, K., Derbenev, Ya. S., Kondratenko, A. M., Orlov, Y. F., Stephenson, E. J., Brantjes, N. P. M., Onderwater, C. J. G., and da Silva, M.

Subjects
Physics - Accelerator Physics
Abstract

This submission was withdrawn because of an unresolved dispute between the authors [arXiv admin 2009-4-13]., Comment: This submission was withdrawn because of an unresolved dispute between the authors [arXiv admin 2009-4-13]

Published
2009

14. Low Temperature Penetration depth of \kappa-(ET)_2Cu[N(CN)_2]Br and \kappa-(ET)_2Cu(NCS)_2

Author

Carrington, A., Bonalde, I. J., Prozorov, R., Giannetta, R. W., Kini, A. M., Schlueter, J., Wang, H. H., Geiser, U., and Williams, J. M.

Subjects
Condensed Matter - Superconductivity
Abstract

We present high precision measurements of the penetration depth \lambda of single crystals of \kappa-(ET)_2Cu[N(CN)2]Br and \kappa-(ET)_2Cu(NCS)_2 at temperature down to 0.4 K. We find that, at low temperatures, the in-plane penetration depth varies as a fractional power law, \lambda\sim T^1.5. W hilst this may be taken as evidence for novel bose excitation processes, we show that the data are also consistent with a quasi-linear variation of the superfluid density, as is expected for a d-wave superconductor with impurities. Our data for the interplane penetration depth show similar features and give a direct measurement of the absolute value, \lambda(0)=100\pm 20 \mu m., Comment: 4 pages, 4 postscript figures

Published
1999
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15. Validity and Reliability of the Home Management of Diarrhoea Assessment Scale for Mothers in Nigeria: A Rasch Analysis.

Author

Ogbonnaya, C. E., Chinweuba, A. U., Ogbonnaya, N. P., Ihudiebube-Splendor, C. N., and Williams, J. M.

Subjects
DIARRHEA, MOTHERS, LITERATURE reviews, MEDICAL personnel, CHILD death
Abstract

In Nigeria, 151,700 children die every year from diarrhoea disease. The use of a valid and reliable tool for eliciting information on what mothers do at home to manage diarrhoea is critical for healthcare providers and researchers. The study aimed to develop and validate the Home Management of Diarrhoea Assessment Scale (HMDAS) using Rasch Analysis among mothers of underfives in Nigeria. The cross-sectional survey design was employed among 376 mothers in one selected local government area in each of the 6 geopolitical zones of Nigeria recruited using multi-stage sampling technique. Data were collected for 6 months and were subjected to descriptive statistics and Rasch analysis. The HMDAS was developed after in-depth literature review and 3 rounds of input from 5 expert reviewers. fit analysis revealed that 12 items were misfits and were expunged from the tool. The HMDAS was found to be unidimensional with Eigen value of less than 1. Item and person separation index of the HMDAS were 11.1917 and 2.0123 respectively. Item and the person reliability index of the HMDAS were 0.9121 and 0.0820. The HMDAS was concluded to be a reliable and valid tool for data collection. It was recommended that the HMDAS should be utilized in generating data that can be used for designing interventions aimed at stemming the tide of diarrhoea in Nigeria. [ABSTRACT FROM AUTHOR]

Published
2024
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18. Modelling Losses in Superconducting Travelling Wave Parametric Amplifiers

Author

Ó Peatáin, Searbhán, Dixon, T., Meeson, P. J., Williams, J. M., Kafanov, Sergey, Pashkin, Yuri, Ó Peatáin, Searbhán, Dixon, T., Meeson, P. J., Williams, J. M., Kafanov, Sergey, and Pashkin, Yuri

Abstract

Parametric amplifiers based on non-linear superconducting transmission lines have seen rapid progress in the last few years, although many fabricated samples still behave well below the optimal performance that is theorised. A part of this discrepancy is due to the attenuation of travelling waves that occurs in realised schemes due to dielectric losses or resistance losses on the superconductor surface. As interests turn towards designs utilising more complex non-linear elements such as SNAILs or materials near the superconductor–insulator transition, we address the question of dissipative losses in heretofore common schemes with a methodology that can be extended to other superconducting metamaterial devices.

Published
2023

19. CLIMATE CHANGE AND TOPOGRAPHY FOCUSED AEOLIAN EROSION IN GALE CRATER, MARS -TEN-YEARS OF MSL OBSERVATIONS

Author

Newsom, H. E., Hoffman, M. E., Gallegos, Z. E., Williams, J. M., Los, S. A., Dimitracopoulos, F. D., Nellessen, M. A., Mason, D., Scuderi, L. A., Crossey, L. J., Gasda, P.J., Lanza, N., Gasnault, O., Kite, E. S., Dietrich, W. E., Institute of Meteoritics [Albuquerque] (IOM), The University of New Mexico [Albuquerque], Los Alamos National Laboratory (LANL), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Lunar and Planetary Institute

Subjects
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract

International audience

Published
2023

21. A method for using Josephson voltage standards for direct characterization of high performance digitizers to establish AC voltage and current traceability to SI

Author

Ireland, J, primary, Reuvekamp, P G, additional, Williams, J M, additional, Peral, D, additional, Díaz de Aguilar, J, additional, Sanmamed, Y A, additional, Šíra, M, additional, Mašláň, S, additional, Rzodkiewicz, W, additional, Bruszewski, P, additional, Sadkowski, G, additional, Sosso, A, additional, Cabral, V, additional, Malmbekk, H, additional, Pokatilov, A, additional, Herick, J, additional, Behr, R, additional, Coşkun Öztürk, T, additional, Arifoviç, M, additional, and Ilić, D, additional

Published
2022
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29. Assessment and Multimedia Authoring - A Tool for Externalising Understanding.

Author

McFarlane, A. E., Williams, J. M., and Bonnett, M.

Abstract

Discusses multimedia authoring software that uses hypertext and reviews the ways in which use of this technology may support improvements in assessment. Describes research with sixth graders in England that investigated how pupil-produced multimedia documents can reveal aspects of performance that traditional tests may not recognize. (Author/LRW)

Published
2000

31. A method for using Josephson voltage standards for direct characterization of high performance digitizers to establish AC voltage and current traceability to SI.

Author

Ireland, J, Reuvekamp, P G, Williams, J M, Peral, D, DĂ-az de Aguilar, J, Sanmamed, Y A, Ĺ Ă-ra, M, Mašláň, S, Rzodkiewicz, W, Bruszewski, P, Sadkowski, G, Sosso, A, Cabral, V, Malmbekk, H, Pokatilov, A, Herick, J, Behr, R, CoĹźkun Ă–ztĂĽrk, T, Arifoviç, M, and Ilić, D

Subjects
VOLTAGE dividers, VOLTAGE, TIME measurements, VOLTAGE-frequency converters
Abstract

A method for traceability to SI for ac voltage and current based on high performance digitizers is presented. In contrast to the existing thermal-based methods, the proposed method utilizes direct traceability to quantum-based waveforms via the use of Josephson voltage systems. This allows not only a simplification of the traceability chain and reduced measurement times but also offers the potential for analysis of the ac voltage and current waveform spectral content, a feature which is not possible using thermal methods. Scaling of current and voltage is achieved by the use of current shunts and resistive voltage dividers respectively. Target operating ranges are up to 1 A and 100 V with a frequency range up to 1 kHz for both. The corresponding target uncertainty for this traceability route is 1 ÎĽV Vâˆ'1 and 2 ÎĽA Aâˆ'1 up to frequencies of 1 kHz. The traceability chain is described and various components are characterized to validate their suitability for this task. It is demonstrated that these uncertainty targets can be met under certain conditions. The use of multi-tone calibration waveforms is investigated to further reduce measurement time. An uncertainty analysis method based on simulation using real component performance data is demonstrated. [ABSTRACT FROM AUTHOR]

Published
2023
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33. Fluid Sampling under Adverse Conditions Echantillonnage des fluides en conditions difficiles

Author

Williams J. M.

Subjects
Chemical technology, TP1-1185, Energy industries. Energy policy. Fuel trade, HD9502-9502.5
Abstract

Valid samples are essential to the proper description of reservoir fluids; if the samples are not representative, all measurements on them will be invalid. This paper discusses the principal challenges facing fluid sampling including gas condensate reservoirs, compositional gradients, water content of hydrocarbon fluids, asphaltene deposition, wax formation, oil base mud contamination, and reactive components. It also reports the major technological advances recently made in this field. It reviews developments in sampling techniques such as MDT-type tools, new DST sampling tools, coiled tubing sampling, and isokinetic techniques, and it highlights common limitations. The value of making proper use of existing technology is emphasized, both with traditional techniques and new developments, with reference to correct well conditioning, interpretation of field data, and especially to optimum handling of samples. The paper emphasizes the need for better exchange of sampling knowledge between organizations, and highlights the lack of up-to-date industry standards with respect to fluid sampling. A solution is proposed in the form of a joint industry project to identify and document best practices. Des échantillons valables sont essentiels pour bien caractériser les fluides de gisements. Si les échantillons ne sont pas représentatifs, toutes les mesures ultérieures seront entachées d'erreurs. Cet article discute les principaux défis en matière d'échantillonnage, en particulier les réservoirs de gaz à condensats, les gradients compositionnels, la teneur en eau des fluides hydrocarbonés, les dépôts d'asphaltènes, les dépôts de paraffines, la contamination par les boues à base d'huile, et les constituants réactifs. Il relate également les principaux progrès technologiques récemment réalisés dans ce domaine et passe en revue les développements des techniques d'échantillonnage telles que les outils de type MDT, les nouveaux outils d'échantillonnage DST, l'échantillonnage par coiled tubing, et les méthodes isocinétiques. Il met également l'accent sur leurs limites. On insiste sur l'importance d'un usage optimal de la technologie existante, par combinaison des techniques traditionnelles et des développements nouveaux, qu'il s'agisse du conditionnement correct du puits, de l'interprétation des données du champ, ou surtout d'une manipulation adéquate des échantillons. Cet article insiste aussi sur le besoin d'un meilleur échange d'informations sur l'échantillonnage entre organisations, et rappelle le manque de normes industrielles à jour en matière d'échantillonnage des fluides. Il est proposé de constituer un projet industriel pour identifier et documenter les procédures adéquates.

Published
2006
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39. An online survey of equestrian headcollar use and safety

Author

Marlin, D. J., Williams, J. M., and Pickles, K. J.

Subjects
Equine
Abstract

BackgroundHeadcollars (halters, US) are one of the most commonly used pieces of equestrian ‘tack’. Despite this, there appears to be minimal information on their use, or more importantly, risk factors for injury of horses/handlers.ObjectiveTo explore headcollar use and safety in equestrians.Study designQuantitative cross-sectional survey.MethodsAn online survey (19 questions) exploring headcollar use and safety was disseminated through equestrian social media. Frequency analysis and multivariable modelling identified how headcollar type was linked to use and injury risk.ResultsMost respondents (88%; n = 4786) used headcollars multiple times daily but for short time periods (66%, n = 3388

Published
2021

47. Projectile Motion: The 'Coming and Going' Phenomenon

Author

Williams J. M. Ribeiro and J. Ricardo de Sousa

Subjects
Physics, Resistive touchscreen, Projectile motion, General Physics and Astronomy, Reynolds number, Mechanics, Motion (physics), Education, TRAJETÓRIA, symbols.namesake, Quadratic equation, Drag, Phenomenon, symbols
Abstract

During elementary physics courses, many examples in mechanics are studied without considering air resistance effects. We can mention, for example, projectile motion and free fall, among many others. Only brief studies of such systems in classical mechanics courses consider linear air resistance (Fdrag ∝ v), which is the simplest model to account for the drag effect by modeling objects moving in viscous media with small velocities (more precisely, small Reynolds number). Quadratic air resistance (Fdrag ∝ v2), which applies for objects moving in resistive media with high velocities (high Reynolds number), is hardly mentioned, but it can be found in many papers. However, in nature air resistance plays a big role in the motion of bodies and so it must be included when studying any kind of phenomena related to mechanics.

Published
2021

49. Evaluating what students know: using the RosE portfolio system for institutional and program outcomes assessment tutorial

Author

Williams, J. M.

Subjects
Accreditation (Education) -- Analysis, Educational evaluation -- Planning, Universities and colleges -- Indiana, Universities and colleges -- Management, Universities and colleges -- Curricula, Company business planning, Company business management, Business, High technology industry, Literature/writing, Rose-Hulman Institute of Technology -- Management, Rose-Hulman Institute of Technology -- Curricula
Published
2010

50. An online survey of equestrian headcollar use and safety.

Author

Marlin, D. J., Williams, J. M., and Pickles, K. J.

Subjects
*HORSE health, *INTERNET surveys, *INJURY risk factors, *RECOLLECTION (Psychology), *HORSEMEN & horsewomen, *THEMATIC analysis
Abstract

Summary: Background: Headcollars (halters, US) are one of the most commonly used pieces of equestrian 'tack'. Despite this, there appears to be minimal information on their use, or more importantly, risk factors for injury of horses/handlers. Objective: To explore headcollar use and safety in equestrians. Study design: Quantitative cross‐sectional survey. Methods: An online survey (19 questions) exploring headcollar use and safety was disseminated through equestrian social media. Frequency analysis and multivariable modelling identified how headcollar type was linked to use and injury risk. Results: Most respondents (88%; n = 4786) used headcollars multiple times daily but for short time periods (66%, n = 3388, <30 min). A horse being injured as a result of wearing a headcollar was reported by 1615 (31%) respondents with 15% of incidents also injuring a person. Fractures (horses) occurred in 134 incidents, and 167 equine fatalities were reported. Across all headcollar types, the odds of injury risk increased by 1.7 times (confidence intervals (CI): 1.07–2.41, P<0.02) using a headcollar when mucking out. During travelling, headcollar use reduced the odds of risk of injury by 0.7 times (CI: 0.43–0.98, P<0.04). The odds of injury risk reduced when using leather (Odds ratio (OR): 0.8, CI: 0.66–0.96, P<0.01) or synthetic (OR: 0.8, CI: 0.58–0.85, P<0.0001) safety headcollars compared with standard headcollars of the same material. Thematic analysis identified three key themes: (1) need for increased education: fit, safety features and basic horse handling, (2) 'safer' leather headcollars, and (3) increased safety focus required. Main limitations: Data were self‐reported and may be subject to memory recall errors; online surveys are subject to self‐selection bias. Conclusions: Increased user knowledge of risk factors for headcollar injury, combined with standardised guidance on how to correctly fit and use headcollars, would be beneficial to reduce injury risk. [ABSTRACT FROM AUTHOR]

Published
2022
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