Jan 10 – 15, 2021
Weizmann Institute of Science
Asia/Jerusalem timezone
See you at IS2023 in Copenhagen in June 2023

Measurement of the sensitivity of two particle correlations in $pp$ collisions at $\sqrt{s}=13$~TeV to the presence of jets with the ATLAS detector

Jan 10, 2021, 7:45 PM
1h 30m
Patio (vDLCC)



bullet talk (poster) Collective dynamics from small to large systems Poster


Pengqi Yin (Columbia University (US))


Measurements of two-particle correlations in $pp$ collisions show the presence of
long-range correlations along $\Delta\eta$ that are strikingly similar to
those seen in heavy-ion collisions.
In heavy-ion collisions, the long-range correlations are known to arise from the
collective dynamics of the produced quark-gluon plasma (QGP).
The similarity between the $pp$ and heavy-ion measurements raises the possibility
that a tiny droplet of the QGP is produced even in $pp$ collisions.
However, models that attribute the correlation in $pp$ collisions to semi-hard processes
can qualitatively reproduce the measurements.
Thus performing the $pp$ measurements with an active rejection
of particles associated with semi-hard processes, such as low-$p_{\mathrm{T}}$ jets,
can further elucidate the origin of the long-range correlations.
This poster presents measurements of two-particle correlations in $pp$ collisions
at $\sqrt{s}=13$~TeV, when removing tracks associated with jets from the event.
The jets are reconstructed from tracks using the anti-$k_t$ algorithm, and all tracks
within one unit of pseudorapidity of the jet are removed from the correlation analysis.
It is demonstrated that such removal of particles in the vicinity of jets
affects the magnitude of long-range correlations only by a few percent.

Primary author

Pengqi Yin (Columbia University (US))

Presentation materials