Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userPrompt $Lambda^+_c$ production in $pmathrm{Pb}$ collisions at $sqrt{s_{NN}} = 5.02$ TeV
83
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
The production of $Lambda^+_c$ baryons produced directly at the interacting point is studied in proton-lead collisions collected with the LHCb detector at the LHC. The data sample corresponds to an integrated luminosity of $1.58mathrm{nb}^{-1}$ recorded at a nucleon-nucleon centre-of-mass energy of $sqrt{s_{NN}}=5.02$ TeV. Measurements of the differential cross-section and the forward-backward production ratio are reported for $Lambda^+_c$ baryons with transverse momenta in the range $2<p_{T}<10$GeV/$c$ and rapidities in the ranges $1.5<y^*<4.0$ and $-4.5<y^*<-2.5$ in the nucleon-nucleon centre-of-mass system. The ratio of cross-sections of $Lambda^+_c$ baryons and $D^0$ mesons is also reported. The results are compared with next-to-leading order calculations that use nuclear parton distribution functions.
rate research
Read More
The production of prompt charged particles in proton-lead collisions and in proton-proton collisions at the nucleon-nucleon centre-of-mass energy ${sqrt{s_{scriptscriptstylemathrm{NN}}}=5,mathrm{TeV}}$ is studied at LHCb as a function of pseudorapidity ($eta$) and transverse momentum ($p_{mathrm{T}}$) with respect to the proton beam direction. The nuclear modification factor for charged particles is determined as a function of $eta$ between ${-4.8<eta<-2.5}$ (backward region) and ${2.0<eta<4.8}$ (forward region), and $p_{mathrm{T}}$ between ${0.2<p_{mathrm{T}}<8.0,mathrm{GeV}/c}$. The results show a suppression of charged particle production in proton-lead collisions relative to proton-proton collisions in the forward region and an enhancement in the backward region for $p_{mathrm{T}}$ larger than $1.5,mathrm{GeV}/c$. This measurement constrains nuclear PDFs and saturation models at previously unexplored values of the parton momentum fraction down to $10^{-6}$.
The production of $Upsilon(nS)$ mesons ($n=1,2,3$) in $p$Pb and Pb$p$ collisions at a centre-of-mass energy per nucleon pair $sqrt{s_{NN}}=8.16$ TeV is measured by the LHCb experiment, using a data sample corresponding to an integrated luminosity of 31.8 nb$^{-1}$. The $Upsilon(nS)$ mesons are reconstructed through their decays into two opposite-sign muons. The measurements comprise the differential production cross-sections of the $Upsilon(1S)$ and $Upsilon(2S)$ states, their forward-to-backward ratios and nuclear modification factors, performed as a function of the transverse momentum pt and rapidity in the nucleon-nucleon centre-of-mass frame $y^*$ of the $Upsilon(nS)$ states, in the kinematic range $p_{rm{T}}<25$ GeV/$c$ and $1.5<y^*<4.0$ ($-5.0<y^*<-2.5$) for $p$Pb (Pb$p$) collisions. In addition, production cross-sections for $Upsilon(3S)$ are measured integrated over phase space and the production ratios between all three $Upsilon(nS)$ states are determined. The measurements are compared to theoretical predictions and suppressions for quarkonium in $p$Pb collisions are observed.
The ALICE data on light flavor hadron production obtained in $p-Pb$ collisions at $sqrt{s_{NN}} $ = 5.02 TeV are studied in the thermal model using the canonical approach with exact strangeness conservation. The chemical freeze-out temperature is independent of centrality except for the lowest multiplicity bin, with values close to 160 MeV but consistent with those obtained in $Pb-Pb$ collisions at $sqrt{s_{NN}}$ = 2.76 TeV. The value of the strangeness non-equilibrium factor $gamma_s$ is slowly increasing with multiplicity from 0.9 to 0.96, i.e. it is always very close to full chemical equilibrium.
The production of J/$psi$ mesons is studied in proton-lead collisions at the centre-of-mass energy per nucleon pair $sqrt{s_{text{NN}}}=8.16$ TeV with the LHCb detector at the LHC. The double differential cross-sections of prompt and nonprompt J/$psi$ production are measured as functions of the J/$psi$ transverse momentum and rapidity in the nucleon-nucleon centre-of-mass frame. Forward-to-backward ratios and nuclear modification factors are determined. The results are compared with theoretical calculations based on collinear factorisation using nuclear parton distribution functions, on the colour glass condensate or on coherent energy loss models.
This Letter reports the first measurement of prompt $chi_{c1}$ and $chi_{c2}$ charmonium production in nuclear collisions at Large Hadron Collider energies. The cross-section ratio $sigma(chi_{c2}) / sigma(chi_{c1})$ is measured in $p$Pb collisions at $sqrt{s_{NN}}$ = 8.16 TeV, collected with the LHCb experiment. The $chi_{c1,2}$ states are reconstructed via their decay to a $rm{J}/psi$ meson, subsequently decaying into a pair of oppositely charged muons, and a photon, which is reconstructed in the calorimeter or via its conversion in the detector material. The cross-section ratio is consistent with unity in the two considered rapidity regions. Comparison with a corresponding cross-section ratio previously measured by the LHCb collaboration in $pp$ collisions suggests that $chi_{c1}$ and $chi_{c2}$ states are similarly affected by nuclear effects occurring in $p$Pb collisions.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
