9th International Workshop on Multiple Partonic Interactions at the LHC

Session

WG5: High Multiplicities

12 Dec 2017, 17:00

Conference Hall (Hotel Peterhoff, Shimla, India)

48. Energy and multiplicity dependence of the strangeness enhancement in pp collisions

Francesca Bellini (CERN)

12/12/2017, 17:00

Energy and multiplicity dependence of the strangeness enhancement in pp collisions

The ratio of the $p_{\rm T}$-integrated yield of strange and multi-strange particles relative to non-strange hadrons has been measured as a function of the event activity in pp collisions at the LHC, revealing that from low to high multiplicity events, strange hadron production increases smoothly and...

59. Multiplicity Dependence of Non-extensive Parameters for Strange and Multi-Strange Particles in Proton-Proton Collisions at √s = 7 TeV at the LHC

Arvind Khuntia (Indian Institute of Technology Indore (IN))

12/12/2017, 17:20

High-energy heavy-ion collisions at RHIC and LHC provide a unique opportunity to study nuclear matter under extreme conditions i.e. at high temperature and/or
energy density. Due to the high multiplicities produced in $p+p$ collisions, one can use the the statistical models to describe the particle production mechanism. As thermodynamically consistent Tsallis statistics has been...

23. Multiplicity dependence of light flavour hadron production at LHC energies in the strangeness canonical suppression picture

Alexander Philipp Kalweit (CERN)

12/12/2017, 17:40

The recently observed phenomenon of enhanced strange particle production in high multiplicity pp collisions at LHC is not yet well understood from a theoretical point of view. While a modelling based on QCD inspired MC models such as PYTHIA, DIPSY or EPOS aims at a microscopic understanding, we present two alternative approaches to study light flavour hadron production as a function of event...

45. New results on multiplicity and event shape dependence of particle production in pp collisions

Mr Sushanta Tripathy (Indian Institute of Technology Indore (IN))

12/12/2017, 18:00

Event shape observables are important tools to get an insight into the physics behind collective phenomena in high multiplicity pp collisions at LHC energies. They can be used to disentangle the contributions from hard and soft processes to particle production. We report measurements with the ALICE detector at the LHC of the production of inclusive and identified charged particles as a...

21. Multiple Partonic Interaction and production of Charmonia in proton+proton collisions at the LHC energies

Raghunath Sahoo (Indian Institute of Technology Indore (IN))

12/12/2017, 18:20

In high multiplicity p+p collisions, the Underlying Event observable is of great interest to the scientific community. The Multiple Partonic Interaction (MPI) is one of them, where several inelastic interactions at partonic level occur in a single p+p collision. In general, MPI plays an important role to produce light quarks and gluons. But it is observed that it can also contribute to...

20. J/psi production as a function of charged particle multiplicity in ALICE at the LHC

Dhananjaya Thakur (Indian Institute of Technology Indore (IN))

12/12/2017, 18:40

Details of charmonium production in hadronic collisions are still under active investigation in the scientific community. The event multiplicity dependence of J/psi production will give insight into the processes at the parton level. Multiple Parton Interactions (MPI) are thought to be a substantial source of hard scattering processes at LHC energies. Here, several inelastic scatterings occur...

76. Collectivity from interference

Boris Blok (Physics Department)

12/12/2017, 19:00

In hadronic collisions, interference between different production channels af-
fects momentum distributions of multi-particle final states. As this QCD interference does
not depend on the strong coupling constant
$\alpha_s$, it is part of the no-interaction baseline that
needs to be controlled prior to searching for other manifestations of collective dynamics,
e.g., in the analysis of...

44. Multiplicity dependence study of the pseudorapidity density distribution of charged particles in pp collisions with ALICE

Mr Prabhakar Palni (For ALICE Collaboration)

13/12/2017, 09:00

In this contribution, we report on the multiplicity dependence of the pseudorapidity density distribution of charged particles in proton-proton (pp) collisions at $\sqrt{s}$ = 5.02 TeV and at 13 TeV with the ALICE experiment. The measurements rely on track segments reconstructed with the Silicon Pixel Detector in the kinematic region $|\eta| < $ 1.8. Results are presented for three different...

25. Initial state effects and collectivity in p+p and p+A collisions at the LHC

Prithwish Tribedy (Brookhaven National Lab)

13/12/2017, 09:20

In this talk I will discuss on the latest developments in the theoretical description of small collision systems at the LHC. In particular I will discuss how our understanding of the initial state geometry and momentum space correlations can help explain the origin of collectivity in small collision systems at the LHC.

65. Two-particle correlation and flow of identified hadrons in small systems at LHC energies

Mr Kishora Nayak (National Institute of Science Education and Research, HBNI, Jatni)

14/12/2017, 11:00

Recent measurements in proton-proton (pp) and proton-nucleus (pA) collisions at LHC energies show that the charged particle multiplicity density is comparable to that produced in nuclear collisions at lower energies. The long-range "ridge" structures observed in high multiplicity pp and p-Pb collisions resemble those seen in Pb-Pb collisions. The "ridge" structure in Pb-Pb collisions suggests...

28. Charged-particle multiplicity dependence of open heavy-flavour production in pp collisions with ALICE at the LHC

Massimiliano Marchisone (Universite Claude Bernard Lyon I (FR))

14/12/2017, 11:20

Heavy-flavour production in pp collisions at LHC energies is described by perturbative QCD calculations based on the factorization approach in which the cross-section is obtained as a convolution of a hard process, parton distribution functions and fragmentation functions. The investigation of heavy-flavour production as a function of event properties, like charged-particle multiplicity, can...

51. Energy and multiplicity dependence of identified charged particle production in pp collisions

Natasha Sharma (Panjab University (IN))

14/12/2017, 11:40

In recent years, the ALICE experiment has collected data in proton-proton
collisions at various centre-of-mass energies. In addition to providing a
baseline for heavy-ion collisions, these data provide information on the
particle production in high energy collisions through the study of energy
dependence of various observables. With large statistics data samples
collected in pp at $\sqrt{s}~=$...

22. Particle transverse momentum distributions in p-p Collisions at √sNN = 0.9 TeV

Mr Rameez Ahmad Parra (Jamia Millia Islamia)

14/12/2017, 12:00

The mid-rapidity transverse momentum spectra of hadrons ( p, K+, ks0, lambda, lambda-bar and cascade and the available rapidity distributions of the strange hadrons produced in p-p collisions at LHC energy √sNN = 0.9 TeV have been studied using a Unified Statistical Thermal Freeze-out Model (USTFM). The calculated results are found to be in good agreement with the experimental data.The...