We report on the latest measurements of the production of ϒ mesons in heavy-ion collisions from the STAR experiment at RHIC. New measurements of the nuclear modification factors of the ϒ(1S+2S+3S) ...and ϒ(1S) states in U+U collisions at sNN=193 GeV are presented as a function of the number of participants (Npart) in the collisions. In addition, the suppression of ϒ(1S) and ϒ(2S+2S) is presented versus the quark-antiquark binding energy. Preliminary results on ϒ suppression in Au+Au collisions at sNN=200 GeV, reconstructed via the dimuon channel, are also reported.
A selection of new jet substructure measurements are reported from the ALICE experiment at the CERN LHC in both proton-proton and heavy-ion collisions. These include the first fully corrected ...inclusive measurements of the groomed jet momentum fraction and the groomed jet radius, as well as the
-subjettiness distribution and the fragmentation distribution of reclustered subjets. We also report on the measurement of several groomed substructure observables of heavy-flavor jets in
pp
collisions, fragmentation functions and the new measurements of the radial distributions of
D
mesons or
baryons in jets. The measurements are compared to theoretical calculations and provide new constraints on the physics underlying parton fragmentation and jet quenching.
A reduction of the mass of the η' (958) meson may indicate the restoration of the UA(1) symmetry in a hot and dense hadronic matter, corresponding to the return of the 9th, "prodigal" Goldstone ...boson. We report on an analysis of a combined PHENIX and STAR data set on the intercept parameter of the two-pion Bose-Einstein correlation functions, as measuremed in √sNN = 200 GeV Au+Au collisions at RHIC. To describe this combined PHENIX and STAR dataset, an in-medium η' mass reduction of at least 200 MeV is needed, at the 99.9 % confidence level in a broad model class of resonance multiplicities. Energy, system size and centrality dependence of the observed effect is also discussed.
PHENIX and STAR data on the intercept parameter of the two-pion Bose-Einstein correlation functions in
s
N
N
=
200
GeV
Au+Au collisions were analysed in terms of various models of hadronic ...abundances. To describe these data, an in-medium
η
′
mass decrease of at least 200 MeV was needed in these models.
PHENIX Collaboration and STAR Collaboration data on the intercept parameter of the two-pion Bose-Einstein correlation functions in √ s{NN}=200 GeV Au+Au collisions are analyzed in terms of different ...models of hadronic multiplicities. To describe this combined PHENIX and STAR data set, an in-medium η' mass reduction of at least 200 MeV is needed, at the 99.9% confidence level in the considered model class. Such a significant η' mass modification may indicate the restoration of the U{A}(1) symmetry in a hot and dense hadronic matter and the return of the 9th "prodigal" Goldstone boson.
PHENIX Collaboration and STAR Collaboration data on the intercept parameter of the two-pion Bose-Einstein correlation functions in {radical}(s{sub NN})=200 GeV Au+Au collisions are analyzed in terms ...of different models of hadronic multiplicities. To describe this combined PHENIX and STAR data set, an in-medium {eta}{sup '} mass reduction of at least 200 MeV is needed, at the 99.9% confidence level in the considered model class. Such a significant {eta}{sup '} mass modification may indicate the restoration of the U{sub A}(1) symmetry in a hot and dense hadronic matter and the return of the 9th ''prodigal'' Goldstone boson.
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