Measurement of the production of neighbouring jets in lead-lead collisions at $\sqrt{s_{\mathrm{NN}}} = 2.76$ TeV with the ATLAS detector

• Published in: Physics letters. B 2015-06, Vol.751, p.376-395
• Main Authors: Aad, G., Albrand, S., Brown, J., Collot, J., Crépé-Renaudin, S., Dechenaux, B., Delsart, P.A., Gabaldon, C., Genest, M.H., Hostachy, J.Y., Ledroit-Guillon, F., Lleres, A., Lucotte, A., Malek, F., Monini, C., Stark, J., Trocmé, B., Wu, M., Rahal, G., Ayoub, M.K., Bassalat, A., Becot, C., Binet, S., Bourdarios, C., de Vivie de Regie, J.B., Delgove, D., Duflot, L., Escalier, M., Fayard, L., Fournier, D., Gkougkousis, E.L., Grivaz, J.-F., Guillemin, T., Hariri, F., Henrot-Versillé, S., Hrivnac, J., Iconomidou-Fayard, L., Kado, M., Lounis, A., Makovec, N., Morange, N., Nellist, C., Poggioli, L., Puzo, P., Renaud, A., Rousseau, D., Rybkin, G., Schaffer, A.C., Scifo, E., Serin, L., Simion, S., Tanaka, R., Tran, H.L., Zerwas, D., Zhang, Z., Zhao, Y., Boumediene, D., Busato, Emmanuel, Calvet, D., Calvet, S., Donini, J., Dubreuil, E., Ghodbane, N., Gilles, G., Gris, Ph, Guicheney, C., Liao, H., Pallin, D., Paredes Hernandez, D., Podlyski, F., Santoni, C., Theveneaux-Pelzer, Timothée, Valery, Loïc, Vazeille, F., Barnovska, Z., Berger, N., Delmastro, M., Di Ciaccio, L., Doan, T.K.O., Elles, S., Goy, C., Hryn’ova, T., Jézéquel, S., Koletsou, I., Lafaye, R., Leveque, J., Massol, N., Sauvage, G., Sauvan, E., Simard, O., Todorov, T., Wingerter-Seez, I., Alio, L., Barbero, M., Bertella, C., Clémens, J. C., Coadou, Y., Diglio, Sara, Djama, F., Feligioni, L.
• Format: Article
• Language: English
• Subjects: High Energy Physics - Experiment; Physics
• ISSN: 0370-2693
• DOI: 10.1016/j.physletb.2015.10.059

This Letter presents measurements of correlated production of nearby jets in Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 2.76$ TeV using the ATLAS detector at the Large Hadron Collider. The measurement was performed using 0.14 ${\rm nb}^{-1}$ of data recorded in 2011. The production of correlated jet pairs was quantified using the rate, $R_{\Delta R}$, of "neighbouring" jets that accompany "test" jets within a given range of angular distance, $\Delta R$, in the pseudorapidity--azimuthal angle plane. The jets were measured in the ATLAS calorimeter and were reconstructed using the anti-$k_{t}$ algorithm with radius parameters $d = 0.2$, $0.3$, and $0.4$. $R_{\Delta R}$ was measured in different Pb+Pb collision centrality bins, characterized by the total transverse energy measured in the forward calorimeters. A centrality dependence of $R_{\Delta R}$ is observed for all three jet radii with $R_{\Delta R}$ found to be lower in central collisions than in peripheral collisions. The ratios formed by the $R_{\Delta R}$ values in different centrality bins and the values in the 40-80 % centrality bin are presented.