arXiv subjects

Isaac Mooney

Publications and source records attributed to Isaac Mooney.

6 recordsLinked to original sources

arXiv2026

STAR Experimental Overview

We highlight some of the STAR collaboration's results on heavy-ion collisions from the past year, addressing many open questions related to the strong interaction under extreme conditions. Topics presented include jet and quarkonium modification in quark-gluon plasma (QGP); collective dynamics of QGP constituents; low-energy and small-sized collisions; and vector meson production from ultraperipheral, photonic ion collisions. Lastly, we end with a conclusion and outlook toward the data-analysis era.

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arXiv2025

Overview of recent results from the STAR experiment

We highlight the STAR experiment's recent measurements on electromagnetic and hard probes of nuclear collisions, which inform the field's understanding of these physical phenomena and by extension QCD. Results on vector meson production from the high electromagnetic fields in glancing heavy-ion collisions are presented. Observables related to jets, high-momentum hadrons, heavy quarks and quarkonia in vacuum and their modification in head-on heavy-ion collisions are also presented. Studies using electromagnetic probes of the medium created in these collisions are presented as well. Finally, we conclude and give an outlook for STAR data-taking and measurements in the coming years.

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arXiv2024

A New Herwig7 Underlying Event Tune: from RHIC to LHC Energies

We present parameter sets corresponding to new underlying event tunes for the Herwig7.3 Monte Carlo event generator. The existing Herwig tunes are in good agreement with LHC data, however, they are not typically designed for center-of-mass energies below $\sqrt{s}=300$ GeV. The tunes presented in this study can describe mid-rapidity data collected at the nominal RHIC energy of $\sqrt{s }=200$ GeV, as well as higher center-of-mass energies utilized by experiments elsewhere, such as the LHC. The base "New Haven" tune is developed by fitting minimum-bias simulations of proton-proton collisions to mid-rapidity identified hadron and jet data from the STAR experiment. The "Nashville" tune includes a separate set of parameters developed by tuning to Tevatron proton-antiproton data at $\sqrt{s}=300$, $900$ and $1960$ GeV from CDF, and LHC proton-proton measurements from CMS at $\sqrt{s}=7$ TeV, in addition to the STAR measurements. Both new tunes demonstrate significant improvements over the recommended default tune currently included in the latest version of Herwig for minimum bias production. As such, we advocate using these tunes for future simulation studies at mid-rapidity by the experimental collaborations at RHIC (STAR and sPHENIX) and the LHC (ATLAS, ALICE, CMS).

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arXiv2024

Understanding perturbative and non-perturbative contributions to jets at RHIC

Jets, as collections of multi-scale objects, allow for insight into perturbative (high-momentum) processes, but gaining an understanding of the non-perturbative structure within jets such as hadronization effects and the underlying event has been more difficult. In observables sensitive to these non-perturbative effects, a large discrepancy is observed between partonic calculations and experimental data at RHIC. Grooming techniques such as SoftDrop reduce the impact of these non-perturbative effects and isolate the hard radiation associated with the hard scattering for more direct comparison to perturbative calculations. By analogy, CollinearDrop can be used to isolate non-perturbative contributions from a different region of the emission phase space, or the Lund plane, although no measurement of a CollinearDrop observable has yet been published. In these proceedings, we review recent progress on experimentally accessing the perturbative and non-perturbative contributions to jets and their substructure, and discuss potential future measurements at RHIC as a road map toward precision QCD at the EIC.

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arXiv2021

PYTHIA 8 underlying event tune For RHIC energies

We report an underlying event tune for the PYTHIA 8 Monte Carlo event generator that is applicable for hadron collisions primarily at $\sqrt{s}$ ranges available at the Relativistic Heavy-Ion Collider (RHIC). We compare our new PYTHIA 8 tuned predictions to mid-rapidity inclusive $\pi^{\pm}$ spectra, jet sub-structure, Drell-Yan production, and underlying event measurements from RHIC and the Tevatron, as well as underlying event data from the Large Hadron Collider. With respect to the default PYTHIA 8 Monash Tune, the new `Detroit' tune shows significant improvements in the description of the experimental data. Additionally, we explore the validity of PYTHIA 8 predictions for forward rapidity $\pi$ in $\sqrt{s}$ = 200 GeV collisions, where neither tune is able to sufficiently describe the data. We advocate for the new tune to be used for PYTHIA 8 studies at current and future RHIC experiments, and discuss future tuning exercises at lower center-of-mass energies, where forward/backward kinematics are essential at the upcoming Electron-Ion collider.

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arXiv2020

Jet substructure in $p$+$p$ and $p$+Au collisions at $\sqrt{s_{\text{NN}}} = 200$ GeV at STAR

In order to attribute the partonic energy loss experienced by jets (jet quenching) observed in A+A collisions to the traversal of partons through the hot QCD medium, it is necessary to examine the cold nuclear matter (CNM) effects on the corresponding jets. Such an examination has historically been done using $p$+A collisions. We present fully corrected measurements of the jet mass and SoftDrop groomed jet mass in $p$+$p$ and $p$+Au collisions at STAR at $\sqrt{s_{\rm{NN}}}=200$ GeV as a function of the event activity (EA) to increase or decrease the magnitude of CNM effects. EA is determined in the backward (Au-going) rapidity ($-5.0<η<-3.3$) by the STAR Beam-Beam Counter to minimize auto-correlation with jets measured at mid-rapidity. Comparison of the jet mass distribution in $p$+Au collisions to that in $p$+$p$ collisions allows for isolation of CNM effects in anticipation of an upcoming jet mass measurement in Au+Au collisions.

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