Altas Energías

THE proton-proton collisions in all their splendor at high multiplicity

by Dr. Aditya Mishra (ICN-UNAM)

Wednesday, 26 February 2020 from to (Mexico/General)
at ICN-UNAM ( Salon de Seminarios de Gravitacion y Altas Energias, A225, 2o nivel, edificio A )
Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Avenida Universidad No. 3000, Col. UNAM-C.U. Distrito Federal, C.P. 04510, México
Description
We will review the recent work done in the investigation of pp collisions
in ICN.  We have opted to investigate the behavior of the basic parameters
in function of multiplicity going to extremely high multiplicities not yet
covered neither in experiments nor in simulations. we will present our study
of the transverse  momentum spectra at high multiplicity giving importance
to the detail shapes of the spectra in what is usually called  "the power
law " tail which, as we will show, is not the case

 We treated PbPb data in a similar way and compare its power-law exponent
with the pp ones to find out the similarities. The second part of the talk
will deal with the possible observation of energy loss in pp collisions.
This was done observing the evolution of transverse momentum spectra for the
jetty and underlying parts of events as a function of multiplicity in pp
collisions at 13 TeV measured at midrapidity (|η| < 0.8) using PYTHIA8 event
generator. I show some results which indicate that the behavior of both the
underlying and hard components are affected by the multiplicity of the
events i.e. the energy density. The behavior of the spectra at very high
multiplicities suggests that the partons suffer energy loss compensated by
an increase in the multiplicity of events. The results tend to suggest a
change of paradigm in our reasoning about the energy loss and reinforce the
similarities of the pp collisions with PbPb ones as strange as this might
look!
Material:
Support Email: alexis@nucleares.unam.mx