Measurements of jet quenching using semi-inclusive hadron+jet distributions in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>p</mml:mi><mml:mi>p</mml:mi></mml:mrow></mml:math> and central Pb-Pb collisions at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msqrt><mml:msub><mml:mi>s</mml:mi><mml:mrow><mml:mi>N</mml:mi><mml:mi>N</mml:mi></mml:mrow></mml:msub></mml:msqrt><mml:mo>=</mml:mo><mml:mn>5.02</mml:mn></mml:mrow></mml:math> TeV
S. Acharya, D. Adamová, G. Aglieri Rinella, M. Agnello, N. Agrawal, Z. Ahammed, S. Ahmad, S. U. Ahn, I. Ahuja, A. Akindinov, M. Al-Turany, D. Aleksandrov, B. Alessandro, H. M. Alfanda, R. Alfaro Molina, Bushra Ali, A. Alici, N. Alizadehvandchali, A. Alkin, J. Alme, G. Alocco, T. Alt, Anna Rita Altamura, I. Altsybeev, J. R. Alvarado, M. N. Anaam, C. Andrei, N. Andreou, A. Andronic, V. Anguelov, F. Antinori, P. Antonioli, N. Apadula, L. Aphecetche, H. Appelshäuser, C. Arata, S. Arcelli, M. Aresti, R. Arnaldi, Jhoao Gabriel Martins Campos Almeida Arneiro, I. C. Arsene, M. Arslandok, A. Augustinus, R. Averbeck, M. D. Azmi, Hitoshi Baba, A. Badalà, J. Bae, Y. W. Baek, X. Bai, R. Bailhache, Y. Bailung, A. Balbino, A. Baldisseri, Bartosz Baliś, D. Banerjee, Z. Banoo, R. Barbera, F. Barile, L. Barioglio, M. Barlou, Banajit Barman, G. G. Barnaföldi, L. S. Barnby, V. Barret, L. Barreto, C. Bartels, K. Barth, E. Bartsch, N. Bastid, S. Basu, G. Batigne, D. Battistini, B. Batyunya, D. Bauri, J. L. Bazo Alba, I. G. Bearden, C. Beattie, P. Becht, D. Behera, I. Belikov, A. D. C. Bell Hechavarria, F. Bellini, R. Bellwied, S. Belokurova, Yael Antonio Vásquez Beltran, G. Bencédi, S. Beolè, Y. Berdnikov, A. Berdnikova, L. Bergmann, Mihaela Gabriela Besoiu, L. Betev, Partha Pratim Bhaduri, A. Bhasin, M. A. Bhat, B. Bhattacharjee, L. Bianchi, N. Bianchi, J. Bielčík
Abstract
The ALICE Collaboration reports measurements of the semi-inclusive distribution of charged-particle jets recoiling from a high transverse momentum (high <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:msub><a:mi>p</a:mi><a:mi mathvariant="normal">T</a:mi></a:msub></a:math>) charged hadron, in <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:mrow><c:mi>p</c:mi><c:mi>p</c:mi></c:mrow></c:math> and central Pb-Pb collisions at center-of-mass energy per nucleon–nucleon collision <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:mrow><d:msqrt><d:msub><d:mi>s</d:mi><d:mi>NN</d:mi></d:msub></d:msqrt><d:mo>=</d:mo><d:mn>5.02</d:mn></d:mrow></d:math> TeV. The large uncorrelated background in central Pb-Pb collisions is corrected using a data-driven statistical approach which enables precise measurement of recoil jet distributions over a broad range in <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"><e:msub><e:mi>p</e:mi><e:mrow><e:mi mathvariant="normal">T</e:mi><e:mo>,</e:mo><e:mi>ch</e:mi><e:mspace width="4pt"/><e:mi>jet</e:mi></e:mrow></e:msub></e:math> and jet resolution parameter <h:math xmlns:h="http://www.w3.org/1998/Math/MathML"><h:mi>R</h:mi></h:math>. Recoil jet yields are reported for <i:math xmlns:i="http://www.w3.org/1998/Math/MathML"><i:mrow><i:mi>R</i:mi><i:mo>=</i:mo><i:mn>0.2</i:mn></i:mrow></i:math>, 0.4, and 0.5 in the range <j:math xmlns:j="http://www.w3.org/1998/Math/MathML"><j:mrow><j:mn>7</j:mn><j:mo><</j:mo><j:msub><j:mi>p</j:mi><j:mrow><j:mi mathvariant="normal">T</j:mi><j:mo>,</j:mo><j:mi>ch</j:mi><j:mspace width="4pt"/><j:mi>jet</j:mi></j:mrow></j:msub><j:mo><</j:mo><j:mn>140</j:mn></j:mrow><j:mo> </j:mo><j:mrow><j:mi>GeV</j:mi><j:mo>/</j:mo><j:mi>c</j:mi></j:mrow></j:math> and <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"><m:mrow><m:mi>π</m:mi><m:mo>/</m:mo><m:mn>2</m:mn><m:mo><</m:mo><m:mi mathvariant="normal">Δ</m:mi><m:mi>φ</m:mi><m:mo><</m:mo><m:mi>π</m:mi></m:mrow></m:math>, where <o:math xmlns:o="http://www.w3.org/1998/Math/MathML"><o:mrow><o:mi mathvariant="normal">Δ</o:mi><o:mi>φ</o:mi></o:mrow></o:math> is the azimuthal angular separation between hadron trigger and recoil jet. The low-<q:math xmlns:q="http://www.w3.org/1998/Math/MathML"><q:msub><q:mi>p</q:mi><q:mrow><q:mi mathvariant="normal">T</q:mi><q:mo>,</q:mo><q:mi>ch</q:mi><q:mspace width="4pt"/><q:mi>jet</q:mi></q:mrow></q:msub></q:math> reach of the measurement explores unique phase space for studying jet quenching, the interaction of jets with the quark–gluon plasma generated in high-energy nuclear collisions. Comparison of <t:math xmlns:t="http://www.w3.org/1998/Math/MathML"><t:msub><t:mi>p</t:mi><t:mrow><t:mi mathvariant="normal">T</t:mi><t:mo>,</t:mo><t:mi>ch</t:mi><t:mspace width="4pt"/><t:mi>jet</t:mi></t:mrow></t:msub></t:math> distributions from <w:math xmlns:w="http://www.w3.org/1998/Math/MathML"><w:mrow><w:mi>p</w:mi><w:mi>p</w:mi></w:mrow></w:math> and central Pb-Pb collisions probes medium-induced jet energy loss and intra-jet broadening, while comparison of their acoplanarity distributions explores in-medium jet scattering and medium response. The measurements are compared to theoretical calculations incorporating jet quenching. ©2024 CERN, for the ALICE Collaboration 2024 CERN