Search for chargino–neutralino pair production in final states with three leptons and missing transverse momentum in $$\sqrt{s} = 13$$ TeV pp collisions with the ATLAS detector
G. Aad, B. Abbott, D. C. Abbott, A. Abed Abud, K. Abeling, D. K. Abhayasinghe, S. H. Abidi, O. S. AbouZeid, H. Abramowicz, H. Abreu, Y. Abulaiti, A. C. Abusleme Hoffman, B. S. Acharya, B. Achkar, L. Adam, C. Adam Bourdarios, L. Adamczyk, L. Adámek, J. Adelman, A. Adıgüzel, S. Adorni, T. Adye, A. A. Affolder, Y. Afik, C. Agapopoulou, M. N. Agaras, J. Agarwala, A. Aggarwal, C. Agheorghiesei, J. A. Aguilar–Saavedra, A. Ahmad, F. Ahmadov, W. S. Ahmed, X. Ai, G. Aielli, S. Akatsuka, M. Akbiyik, T. P. A. Åkesson, A. V. Akimov, K. Al Khoury, G. L. Alberghi, J. Albert, M. J. Alconada Verzini, S. Alderweireldt, M. Aleksa, I. N. Aleksandrov, C. Alexa, T. Alexopoulos, A. Alfonsi, F. Alfonsi, M. Alhroob, B. Ali, S. Ali, M. Aliev, G. Alimonti, C. Allaire, B. M. M. Allbrooke, P. P. Allport, A. Aloisio, F. Alonso, C. Alpigiani, Elio Alunno Camelia, M. Alvarez Estevez, M. G. Alviggi, Y. Amaral Coutinho, A. Ambler, L. Ambroz, C. Amelung, D. Amidei, S. P. Amor Dos Santos, S. Amoroso, C. S. Amrouche, C. Anastopoulos, N. Andari, T. Andeen, J. K. Anders, S. Y. Andrean, A. Andreazza, V. Andrei, S. Angelidakis, A. Angerami, A. V. Anisenkov, A. Annovi, C. Antel, M. T. Anthony, E. Antipov, M. Antonelli, D. J. A. Antrim, F. Anulli, M. Aoki, J. A. Aparisi Pozo, M. A. Aparo, L. Aperio Bella, N. Aranzabal, V. Araujo Ferraz, C. Arcangeletti, A. T. H. Arce, E. Arena, J-F. Arguin, S. Argyropoulos
Abstract
Abstract A search for chargino–neutralino pair production in three-lepton final states with missing transverse momentum is presented. The study is based on a dataset of $$\sqrt{s} = 13$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> <mml:mo>=</mml:mo> <mml:mn>13</mml:mn> </mml:mrow> </mml:math> TeV pp collisions recorded with the ATLAS detector at the LHC, corresponding to an integrated luminosity of 139 $$\hbox {fb}^{-1}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mtext>fb</mml:mtext> <mml:mrow> <mml:mo>-</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> . No significant excess relative to the Standard Model predictions is found in data. The results are interpreted in simplified models of supersymmetry, and statistically combined with results from a previous ATLAS search for compressed spectra in two-lepton final states. Various scenarios for the production and decay of charginos ( $${\tilde{\chi }}^\pm _1$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mrow> <mml:mover> <mml:mi>χ</mml:mi> <mml:mo>~</mml:mo> </mml:mover> </mml:mrow> <mml:mn>1</mml:mn> <mml:mo>±</mml:mo> </mml:msubsup> </mml:math> ) and neutralinos ( $${\tilde{\chi }}^0_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mrow> <mml:mover> <mml:mi>χ</mml:mi> <mml:mo>~</mml:mo> </mml:mover> </mml:mrow> <mml:mn>2</mml:mn> <mml:mn>0</mml:mn> </mml:msubsup> </mml:math> ) are considered. For pure higgsino $${\tilde{\chi }}^\pm _1{\tilde{\chi }}^0_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msubsup> <mml:mrow> <mml:mover> <mml:mi>χ</mml:mi> <mml:mo>~</mml:mo> </mml:mover> </mml:mrow> <mml:mn>1</mml:mn> <mml:mo>±</mml:mo> </mml:msubsup> <mml:msubsup> <mml:mrow> <mml:mover> <mml:mi>χ</mml:mi> <mml:mo>~</mml:mo> </mml:mover> </mml:mrow> <mml:mn>2</mml:mn> <mml:mn>0</mml:mn> </mml:msubsup> </mml:mrow> </mml:math> pair-production scenarios, exclusion limits at 95% confidence level are set on $${\tilde{\chi }}^0_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mrow> <mml:mover> <mml:mi>χ</mml:mi> <mml:mo>~</mml:mo> </mml:mover> </mml:mrow> <mml:mn>2</mml:mn> <mml:mn>0</mml:mn> </mml:msubsup> </mml:math> masses up to 210 GeV. Limits are also set for pure wino $${\tilde{\chi }}^\pm _1{\tilde{\chi }}^0_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msubsup> <mml:mrow> <mml:mover> <mml:mi>χ</mml:mi> <mml:mo>~</mml:mo> </mml:mover> </mml:mrow> <mml:mn>1</mml:mn> <mml:mo>±</mml:mo> </mml:msubsup> <mml:msubsup> <mml:mrow> <mml:mover> <mml:mi>χ</mml:mi> <mml:mo>~</mml:mo> </mml:mover> </mml:mrow> <mml:mn>2</mml:mn> <mml:mn>0</mml:mn> </mml:msubsup> </mml:mrow> </mml:math> pair production, on $${\tilde{\chi }}^0_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mrow> <mml:mover> <mml:mi>χ</mml:mi> <mml:mo>~</mml:mo> </mml:mover> </mml:mrow> <mml:mn>2</mml:mn> <mml:mn>0</mml:mn> </mml:msubsup> </mml:math> masses up to 640 GeV for decays via on-shell W and Z bosons, up to 300 GeV for decays via off-shell W and Z bosons, and up to 190 GeV for decays via W and Standard Model Higgs bosons.