More Like this

1. Studying the interaction between charm and light-flavor mesons

   https://doi.org/10.1103/PhysRevD.110.032004  

   Acharya, S; Adamová, D; Aglieri_Rinella, G; Aglietta, L; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; Ahuja, I; et al (August 2024, Physical Review D)

   The two-particle momentum correlation functions between charm mesons ( ${\mathrm{D}}^{*\pm }$and ${\mathrm{D}}^{\pm }$) and charged light-flavor mesons ( ${\pi }^{\pm }$and ${\mathrm{K}}^{\pm }$) in all charge combinations are measured for the first time by the ALICE Collaboration in high-multiplicity proton–proton collisions at a center-of-mass energy of $\sqrt{s}=13\mathrm{TeV}$. For DK and ${\mathrm{D}}^{*}\mathrm{K}$pairs, the experimental results are in agreement with theoretical predictions of the residual strong interaction based on quantum chromodynamics calculations on the lattice and chiral effective field theory. In the case of $\mathrm{D}\pi$and ${\mathrm{D}}^{*}\pi$pairs, tension between the calculations including strong interactions and the measurement is observed. For all particle pairs, the data can be adequately described by Coulomb interaction only, indicating a shallow interaction between charm and light-flavor mesons. Finally, the scattering lengths governing the residual strong interaction of the $\mathrm{D}\pi$and ${\mathrm{D}}^{*}\pi$systems are determined by fitting the experimental correlation functions with a model that employs a Gaussian potential. The extracted values are small and compatible with zero. © 2024 CERN, for the ALICE Collaboration2024CERN 

   more » « less
2. Probing Strangeness Hadronization with Event-by-Event Production of Multistrange Hadrons

   https://doi.org/10.1103/PhysRevLett.134.022303  

   Acharya, S; Adamová, D; Agarwal, A; Aglieri_Rinella, G; Aglietta, L; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; et al (January 2025, Physical Review Letters)

   This Letter presents the first measurement of event-by-event fluctuations of the net number (difference between the particle and antiparticle multiplicities) of multistrange hadrons ${\mathrm{\Xi }}^{-}$and ${\overline{\mathrm{\Xi }}}^{+}$and its correlation with the net-kaon number using the data collected by the ALICE Collaboration in pp, p-Pb, and Pb-Pb collisions at a center-of-mass energy per nucleon pair $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. The statistical hadronization model with a correlation over three units of rapidity between hadrons having the same and opposite strangeness content successfully describes the results. On the other hand, string-fragmentation models that mainly correlate strange hadrons with opposite strange quark content over a small rapidity range fail to describe the data. © 2025 CERN, for the ALICE Collaboration2025CERN 

   more » « less
3. First Measurement of the $\left|t\right|$ Dependence of Incoherent $J/\psi$ Photonuclear Production

   https://doi.org/10.1103/PhysRevLett.132.162302  

   Acharya, S; Adamová, D; Adler, A; Aglieri_Rinella, G; Agnello, M; Agrawal, N; Ahammed, Z; Ahmad, S; Ahn, S U; Ahuja, I; et al (April 2024, Physical Review Letters)

   The first measurement of the cross section for incoherent photonuclear production of $J/\psi$vector mesons as a function of the Mandelstam $\left|t\right|$variable is presented. The measurement was carried out with the ALICE detector at midrapidity, $\left|y\right|<0.8$, using ultraperipheral collisions of Pb nuclei at a center-of-mass energy per nucleon pair of $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. This rapidity interval corresponds to a Bjorken- $x$range $\left(0.3–1.4\right)\times {10}^{-3}$. Cross sections are given in five $\left|t\right|$intervals in the range $0.04<\left|t\right|<1{\mathrm{GeV}}^2$and compared to the predictions by different models. Models that ignore quantum fluctuations of the gluon density in the colliding hadron predict a $\left|t\right|$dependence of the cross section much steeper than in data. The inclusion of such fluctuations in the same models provides a better description of the data. © 2024 CERN, for the ALICE Collaboration2024CERN 

   more » « less
4. Search for Nuclear Modifications of $B^{+}$ Meson Production in $p$ -Pb Collisions at $\sqrt{s_{\mathrm{NN}}}=8.16\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevLett.134.111903  

   Hayrapetyan, A; Tumasyan, A; Adam, W; Andrejkovic, J W; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Hussain, P S; Jeitler, M; et al (March 2025, Physical Review Letters)

   Nuclear medium effects on $B^{+}$meson production are studied using the binary-collision scaled cross section ratio between events of different charged-particle multiplicities from proton-lead collisions. Data, collected by the CMS experiment in 2016 at a nucleon-nucleon center-of-mass energy of $\sqrt{s_{\mathrm{NN}}}=8.16\mathrm{TeV}$, corresponding to an integrated luminosity of $175{\mathrm{nb}}^{-1}$, were used. The scaling factors in the ratio are determined using a novel approach based on the $Z\to {\mu }^{-}{\mu }^{+}$cross sections measured in the same events. The scaled ratio for $B^{+}$is consistent with unity for all event multiplicities, putting stringent constraints on nuclear modification for heavy flavor. © 2025 CERN, for the CMS Collaboration2025CERN 

   more » « less
5. Combination of Measurements of the Top Quark Mass from Data Collected by the ATLAS and CMS Experiments at $\sqrt{s}=7$ and 8 TeV

   https://doi.org/10.1103/PhysRevLett.132.261902  

   Hayrapetyan, A; Tumasyan, A; Adam, W; Andrejkovic, J W; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Hussain, P S; Jeitler, M; et al (June 2024, Physical Review Letters)

   A combination of fifteen top quark mass measurements performed by the ATLAS and CMS experiments at the LHC is presented. The datasets used correspond to an integrated luminosity of up to 5 and $20{\mathrm{fb}}^{-1}$of proton-proton collisions at center-of-mass energies of 7 and 8 TeV, respectively. The combination includes measurements in top quark pair events that exploit both the semileptonic and hadronic decays of the top quark, and a measurement using events enriched in single top quark production via the electroweak $t$channel. The combination accounts for the correlations between measurements and achieves an improvement in the total uncertainty of 31% relative to the most precise input measurement. The result is $m_t=172.52\pm 0.14\left(\mathrm{stat}\right)\pm 0.30\left(\mathrm{syst}\right)\mathrm{GeV}$, with a total uncertainty of 0.33 GeV. © 2024 CERN, for the CMS and ATLASs Collaboration2024CERN 

   more » « less