Viaux Maira, Nicolas

2024-05-17, Filmer, E. K., Grant, C. M., Jackson, P., Kong, A. X.Y., Pandya, H. D., Potti, H., Ruggeri, T. A., Ting, E. X.L., White, M. J., Gingrich, D. M., Lindon, J. H., Nishu, N., Pinfold, J. L., Cakir, O., Yildiz, H. Duran, Kuday, S., Turk Cakir, I., Sultansoy, S., Adam Bourdarios, C., Arnaez, O., Berger, N., Castillo, F. L., Costanza, F., Delmastro, M., Di Ciaccio, L., Hryn’ova, T., Jézéquel, S., Koletsou, I., Levêque, J., Lewis, D. J., Little, J. D., Lorenzo Martinez, N., Poddar, G., Sanchez Pineda, A., Sauvan, E., Bernardi, G., Bomben, M., Li, A., Li, T., Marchiori, G., Nakkalil, K., Shen, Q., Zhang, Y., Chekanov, S., Darmora, S., Hopkins, W. H., Hoya, J., Love, J., Luongo, N. A., Metcalfe, J., Mete, A. S., Paramonov, A., Proudfoot, J., Van Gemmeren, P., Wamorkar, T., Wang, R., Zhang, J., Cheu, E., Cui, Z., Ghosh, A., Johns, K. A., Lampl, W., Lindley, R. E., Loch, P., Rutherfoord, J. P., Sardain, J., Varnes, E. W., Zhou, H., Zhou, Y., Bakshi Gupta, D., Burghgrave, B., Cardenas, J. C.J., De, K., Farbin, A., Hadavand, H. K., Myers, A. J., Ozturk, N., Usai, G., White, A., Angelidakis, S., Fassouliotis, D., Fountas, L., Gkialas, I., Kourkoumelis, C., Alexopoulos, T., Drivas-Koulouris, I., Gazis, E. N., Kitsaki, C., Maltezos, S., Paraskevopoulos, C., Perganti, M., Tzanis, P., Andeen, T., Burton, C. D., Choi, K., Onyisi, P. U.E., Panchal, D. K., Tost, M., Unal, M., Huseynov, N., Cristian Andres Allendes Flores, BROOKS, WILLIAM K., CARQUIN, EDSON, Fernandez Luengo, S.I., Fuenzalida Garrido, S., PEZOA, RAQUEL, Carolina Robles Gajardo, Tapia Araya, S., VIAUX MAIRA, NICOLAS

Angular correlations between heavy quarks provide a unique probe of the quark-gluon plasma created in ultrarelativistic heavy-ion collisions. Results are presented of a measurement of the azimuthal angle correlations between muons originating from semileptonic decays of heavy quarks produced in 5.02 TeV Pb+Pb and 𝑝⁢𝑝 collisions at the LHC. The muons are measured with transverse momenta and pseudorapidities satisfying 𝑝𝜇T>4  GeV and |𝜂𝜇|<2.4, respectively. The distributions of azimuthal angle separation Δ⁢𝜙 for muon pairs having pseudorapidity separation |Δ⁢𝜂|>0.8, are measured in different Pb+Pb centrality intervals and compared to the same distribution measured in 𝑝⁢𝑝 collisions at the same center-of-mass energy. Results are presented separately for muon pairs with opposite-sign charges, same-sign charges, and all pairs. A clear peak is observed in all Δ⁢𝜙 distributions at Δ⁢𝜙∼𝜋, consistent with the parent heavy-quark pairs being produced via hard-scattering processes. The widths of that peak, characterized using Cauchy-Lorentz fits to the Δ⁢𝜙 distributions, are found to not vary significantly as a function of Pb+Pb collision centrality and are similar for 𝑝⁢𝑝 and Pb+Pb collisions. This observation will provide important constraints on theoretical descriptions of heavy-quark interactions with the quark-gluon plasma.

2024-07-01, Aad, G., Abbott, B., Abeling, K., Abicht, N. J., Abidi, S. H., Aboulhorma, A., Abramowicz, H., Abreu, H., Abulaiti, Y., Acharya, B. S., Adam Bourdarios, C., Adamczyk, L., Adamek, L., Addepalli, S. V., Addison, M. J., Adelman, J., Adiguzel, A., Adye, T., Affolder, A. A., Afik, Y., Agaras, M. N., Agarwala, J., Aggarwal, A., Agheorghiesei, C., Ahmad, A., Ahmadov, F., Ahmed, W. S., Ahuja, S., Ai, X., Aielli, G., Aikot, A., Ait Tamlihat, M., Aitbenchikh, B., Aizenberg, I., Akbiyik, M., Åkesson, T. P.A., Akimov, A. V., Akiyama, D., Akolkar, N. N., Al Khoury, K., Alberghi, G. L., Albert, J., Albicocco, P., Albouy, G. L., Alderweireldt, S., Aleksa, M., Aleksandrov, I. N., Alexa, C., Alexopoulos, T., Alfonsi, F., Algren, M., Alhroob, M., Ali, B., Ali, H. M.J., Ali, S., Alibocus, S. W., Aliev, M., Alimonti, G., Alkakhi, W., Allaire, C., Allbrooke, B. M.M., Allen, J. F., Allendes Flores, C. A., Allport, P. P., Aloisio, A., Alonso, F., Alpigiani, C., Alvarez Estevez, M., Alvarez Fernandez, A., Alves Cardoso, M., Alviggi, M. G., Aly, M., Amaral Coutinho, Y., Ambler, A., Amelung, C., Amerl, M., Ames, C. G., Amidei, D., Amor Dos Santos, S. P., Amos, K. R., Ananiev, V., Anastopoulos, C., Andeen, T., Anders, J. K., Andrean, S. Y., Andreazza, A., Angelidakis, S., Angerami, A., Anisenkov, A. V., Annovi, A., Antel, C., Anthony, M. T., Antipov, E., Antonelli, M., Anulli, F., Aoki, M., Aoki, T., Aparisi Pozo, J. A., Aparo, M. A., Aperio Bella, L., BROOKS, WILLIAM K., CARQUIN, EDSON, Fernandez Luengo, S.I., PEZOA, RAQUEL, Carolina Robles Gajardo, TAPIA, SEBASTIAN, VIAUX MAIRA, NICOLAS

The observation of the electroweak production of single-top-quarks is made using 255 pb−1 of proton-proton collision data recorded at s√=5.02 TeV with the ATLAS detector at the Large Hadron Collider. An event selection is used to identify single-top-quark candidates arising from t-channel production with the top quark decaying semi-leptonically. Events passing the selection are then used to measure the inclusive cross-section for the combined production of single-top-quarks and antiquarks, σ(tq+t¯q), and the ratio Rt between these two. They are measured to be σ(tq+t¯q)=27.1+4.4−4.1(stat.)+4.4−3.7(syst.) pb and Rt=2.73+1.43−0.82(stat.)+1.01−0.29(syst.). The individual single-top-quark (tq) and single-top-antiquark (t¯q) production cross-sections are measured to be σ(tq)=19.8+3.9−3.1(stat.)+2.9−2.2(syst.) pb and σ(t¯q)=7.3+3.2−2.1(stat.)+2.8−1.5(syst.) pb. All measurements are in good agreement with the Standard Model predictions.

2024-07-01, Aad, G., Aakvaag, E., Abbott, B., Abdelhameed, S., Abeling, K., Abicht, N. J., Abidi, S. H., Aboelela, M., Aboulhorma, A., Abramowicz, H., Abreu, H., Abulaiti, Y., Acharya, B. S., Ackermann, A., Adam Bourdarios, C., Adamczyk, L., Addepalli, S. V., Addison, M. J., Adelman, J., Adiguzel, A., Adye, T., Affolder, A. A., Afik, Y., Agaras, M. N., Agarwala, J., Aggarwal, A., Agheorghiesei, C., Ahmad, A., Ahmadov, F., Ahmed, W. S., Ahuja, S., Ai, X., Aielli, G., Aikot, A., Ait Tamlihat, M., Aitbenchikh, B., Akbiyik, M., Åkesson, T. P.A., Akimov, A. V., Akiyama, D., Akolkar, N. N., Aktas, S., Al Khoury, K., Alberghi, G. L., Albert, J., Albicocco, P., Albouy, G. L., Alderweireldt, S., Alegria, Z. L., Aleksa, M., Aleksandrov, I. N., Alexa, C., Alexopoulos, T., Alfonsi, F., Algren, M., Alhroob, M., Ali, B., Ali, H. M.J., Ali, S., Alibocus, S. W., Aliev, M., Alimonti, G., Alkakhi, W., Allaire, C., Allbrooke, B. M.M., Allen, J. F., Allendes Flores, C. A., Allport, P. P., Aloisio, A., Alonso, F., Alpigiani, C., Alsolami, Z. M.K., Alvarez Estevez, M., Alvarez Fernandez, A., Alves Cardoso, M., Alviggi, M. G., Aly, M., Amaral Coutinho, Y., Ambler, A., Amelung, C., Amerl, M., Ames, C. G., Amidei, D., Amirie, K. J., Amor Dos Santos, S. P., Amos, K. R., An, S., Ananiev, V., Anastopoulos, C., Andeen, T., Anders, J. K., Andrean, S. Y., Andreazza, A., Angelidakis, S., Angerami, A., Anisenkov, A. V., Annovi, A., Antel, C., Antipov, E., Antonelli, M., CARQUIN, EDSON, Fernandez Luengo, S.I., Fuenzalida Garrido, S., PEZOA, RAQUEL, Carolina Robles Gajardo, TAPIA, SEBASTIAN, VIAUX MAIRA, NICOLAS

Fiducial and total 𝑊 ± and 𝑍 boson cross sections, their ratios and the ratio of top-antitop-quark pair and 𝑊 -boson fiducial cross sections are measured in proton–proton collisions at a centre-of-mass energy of √𝑠 = 13.6 TeV, corresponding to an integrated luminosity of 29 fb−1 of data collected in 2022 by the ATLAS experiment at the Large Hadron Collider. The measured fiducial cross-section values for 𝑊 + → 𝓁+𝜈, 𝑊 − → 𝓁−𝜈̄, and 𝑍 → 𝓁+𝓁− (𝓁 = 𝑒 or 𝜇) boson productions are 4250 ± 150 pb, 3310 ± 120 pb, and 744 ± 20 pb, respectively, where the uncertainty is the total uncertainty, including that arising from the luminosity of about 2.2%. The measurements are in agreement with Standard-Model predictions calculated at next-to-next-to-leading-order in 𝛼𝑠 , next-to-nextto-leading logarithmic accuracy and next-to-leading-order electroweak accuracy