Measurement of the production cross section of prompt $$ {\Xi}_{\mathrm{c}}^0 $$ baryons at midrapidity in pp collisions at $$ \sqrt{s} $$ = 5.02 TeV
S. Acharya, D. Adamová, A. Adler, J. Adolfsson, G. Aglieri Rinella, M. Agnello, N. Agrawal, Z. Ahammed, S. Ahmad, S. U. Ahn, I. Ahuja, Zaenal Akbar, A. Akindinov, M. Al-Turany, S. N. Alam, D. Aleksandrov, B. Alessandro, H. M. Alfanda, R. Alfaro Molina, B. Ali, Y. Ali, A. Alici, N. Alizadehvandchali, A. Alkin, J. Alme, T. Alt, L. Altenkamper, I. Altsybeev, M. N. Anaam, C. Andrei, D. Andreou, A. Andronic, Massimo Angeletti, V. Anguelov, F. Antinori, P. Antonioli, C. Anuj, N. Apadula, L. Aphecetche, H. Appelshäuser, S. Arcelli, R. Arnaldi, I. C. Arsene, M. Arslandok, A. Augustinus, R. Averbeck, Sizar Aziz, M. D. Azmi, A. Badalà, Y. W. Baek, Xiaozhi Bai, R. Bailhache, Y. Bailung, R. Bala, A. Balbino, A. Baldisseri, Bartosz Baliś, M. Ball, D. Banerjee, R. Barbera, L. Barioglio, M. Barlou, G. G. Barnaföldi, L. S. Barnby, V. Barret, C. Bartels, K. Barth, E. Bartsch, F. Baruffaldi, N. Bastid, S. Basu, G. Batigne, B. Batyunya, D. Bauri, J. L. Bazo Alba, I. G. Bearden, C. Beattie, I. Belikov, A. D. C. Bell Hechavarria, F. Bellini, R. Bellwied, S. Belokurova, V. M. Belyaev, G. Bencedi, S. Beolè, A. Bercuci, Y. Berdnikov, A. Berdnikova, D. Berényi, L. Bergmann, M. G. Besoiu, L. Betev, P. P. Bhaduri, A. Bhasin, I. R. Bhat, M. A. Bhat, B. Bhattacharjee, P. Bhattacharya, L. Bianchi, N. Bianchi
Abstract
A bstract The transverse momentum ( p T ) differential cross section of the charm-strange baryon $$ {\Xi}_{\mathrm{c}}^0 $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Ξ</mml:mi> <mml:mi>c</mml:mi> <mml:mn>0</mml:mn> </mml:msubsup> </mml:math> is measured at midrapidity (| y | < 0.5) via its semileptonic decay into e + Ξ − ν e in pp collisions at $$ \sqrt{s} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> </mml:math> = 5 . 02 TeV with the ALICE detector at the LHC. The ratio of the p T -differential $$ {\Xi}_{\mathrm{c}}^0 $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Ξ</mml:mi> <mml:mi>c</mml:mi> <mml:mn>0</mml:mn> </mml:msubsup> </mml:math> -baryon and D 0 -meson production cross sections is also reported. The measurements are compared with simulations with different tunes of the PYTHIA 8 event generator, with predictions from a statistical hadronisation model (SHM) with a largely augmented set of charm-baryon states beyond the current lists of the Particle Data Group, and with models including hadronisation via quark coalescence. The p T -integrated cross section of prompt $$ {\Xi}_{\mathrm{c}}^0 $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Ξ</mml:mi> <mml:mi>c</mml:mi> <mml:mn>0</mml:mn> </mml:msubsup> </mml:math> -baryon production at midrapidity is also reported, which is used to calculate the baryon-to-meson ratio $$ {\Xi}_{\mathrm{c}}^0 $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>Ξ</mml:mi> <mml:mi>c</mml:mi> <mml:mn>0</mml:mn> </mml:msubsup> </mml:math> / D 0 = 0 . 20 ± 0 . 04 $$ {\left(\mathrm{stat}.\right)}_{-0.07}^{+0.08} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mfenced> <mml:mrow> <mml:mtext>stat</mml:mtext> <mml:mo>.</mml:mo> </mml:mrow> </mml:mfenced> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.07</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.08</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> (syst . ). These results provide an additional indication of a modification of the charm fragmentation from e + e − and e − p collisions to pp collisions.