244 citations · 1.1k across the 41 of their papers we have counts for
44 papers
Rational Q-systems at Root of Unity I. Closed Chains
Jue Hou, Yunfeng Jiang, Yuan Miao
The solution of Bethe ansatz equations for XXZ spin chain with the parameter being a root of unity is infamously subtle. In this work, we develop the rational -system for th…
TUJU21: nuclear PDFs with electroweak-boson data at NNLO
Ilkka Helenius, Marina Walt, Werner Vogelsang
Nuclear parton distribution functions (nPDFs) can be determined in a global QCD analysis using a wide range of experimental data. In addition to older fixed-target deep inelastic s…
A comprehensive guide to the physics and usage of PYTHIA 8.3
Christian Bierlich, Smita Chakraborty, Nishita Desai +11
This manual describes the PYTHIA 8.3 event generator, the most recent version of an evolving physics tool used to answer fundamental questions in particle physics. The program is m…
Snowmass 2021 White Paper: Electron Ion Collider for High Energy Physics
R. Abdul Khalek, U. D'Alesio, M. Arratia +105
Electron Ion Collider (EIC) is a particle accelerator facility planned for construction at Brookhaven National Laboratory on Long Island, New York by the United States Department o…
NNLO nuclear parton distribution functions with electroweak-boson production data from the LHC
Ilkka Helenius, Marina Walt, Werner Vogelsang
We present new sets of nuclear parton distribution functions (nPDFs) at next-to-leading order and next-to-next-to-leading order in perturbative QCD. Our analyses are based on deepl…
Photoproduction of diffractive dijets in Pythia 8
Ilkka Helenius
The new framework for the simulations of hard diffractive events in photoproduction within Pythia 8 is presented. The model, originally introduced for proton-proton collisions, app…
Evidence of shadowing in inelastic nucleon-nucleon cross section
Kari J. Eskola, Ilkka Helenius, Mikko Kuha +1
The Glauber modeling plays a key role in centrality-dependent measurements of heavy-ion collisions. A central input parameter in Glauber models is the inelastic nucleon-nucleon cro…
The Large Hadron-Electron Collider at the HL-LHC
P. Agostini, H. Aksakal, S. Alekhin +333
The Large Hadron electron Collider (LHeC) is designed to move the field of deep inelastic scattering (DIS) to the energy and intensity frontier of particle physics. Exploiting ener…
Shadowing in inelastic nucleon-nucleon cross section?
Kari J. Eskola, Ilkka Helenius, Mikko Kuha +1
Experimental results of inclusive hard-process cross sections in heavy-ion collisions conventionally lean on a normalization computed from Glauber models where the inelastic nucleo…
Impact of dijet and D-meson data from 5.02 TeV p+Pb collisions on nuclear PDFs
Kari J. Eskola, Ilkka Helenius, Petja Paakkinen +1
We discuss the new constraints on gluon parton distribution function (PDF) in lead nucleus, derivable with the Hessian PDF reweighting method from the 5.02 TeV p+Pb measurements of…
A QCD analysis for nuclear PDFs at NNLO
Marina Walt, Ilkka Helenius, Werner Vogelsang
A new QCD analysis for nuclear parton distribution functions (nPDFs) at next-to-leading order (NLO) and next-to-next-to-leading order (NNLO) is presented. The framework of the anal…
Open-source QCD analysis of nuclear parton distribution functions at NLO and NNLO
Marina Walt, Ilkka Helenius, Werner Vogelsang
We present new sets of nuclear parton distribution functions (nPDFs) at next-to-leading order (NLO) and next-to-next-to-leading order (NNLO). Our analyses are based on deeply inela…
Double D-meson production in proton-proton and proton-lead collisions at the LHC
Ilkka Helenius, Hannu Paukkunen
We consider the simultaneous production of two heavy-flavoured hadrons - particularly D mesons - at the LHC. We base our calculations on collinearly factorized QCD at next-to-leadi…
Constraints for nuclear PDFs from the LHCb D-meson data
Kari J. Eskola, Ilkka Helenius, Petja Paakkinen +1
We quantify the impact of LHCb D-meson measurements at on the EPPS16 and nCTEQ15 nuclear PDFs. In our study, the theoretical description of D-meson produc…
A QCD analysis of LHCb D-meson data in p+Pb collisions
Kari J. Eskola, Ilkka Helenius, Petja Paakkinen +1
We scrutinize the recent LHCb data for D-meson production in p+Pb collisions within a next-to-leading order QCD framework. Our calculations are performed in the SACOT-$m_{\rm T…
Hadroproduction of open heavy flavour for PDF analyses
Ilkka Helenius, Hannu Paukkunen
Due to the large masses of the charm and bottom quarks, their production cross sections are calculable within the perturbative QCD. This makes the heavy-quark mesons important obse…
Nuclear gluons at RHIC in a multi-observable approach
Ilkka Helenius, John Lajoie, Joseph D. Osborn +2
We explore the possibility of measuring nuclear gluon distributions at the Relativistic Heavy-Ion Collider (RHIC) with proton-nucleus collisions. In add…
Hard diffraction in photoproduction with Pythia 8
Ilkka Helenius, Christine O. Rasmussen
We present a new framework for modeling hard diffractive events in photoproduction, implemented in the general purpose event generator Pythia 8. The model is an extension of the mo…
PHOTON-2017 conference proceedings
David d'Enterria, Albert de Roeck, Michelangelo Mangano +77
This document collects the proceedings of the PHOTON 2017 conference ("International Conference on the Structure and the Interactions of the Photon", including the 22th "Internatio…
Probing nuclear PDFs with dijets in ultra-peripheral Pb+Pb collisions
Ilkka Helenius
In this talk we apply the photoproduction framework recently implemented into the Pythia 8 Monte Carlo event generator to study the potential of photo-nuclear dijets in ultra-perip…
Heavy flavour production in the SACOT- scheme
Ilkka Helenius, Hannu Paukkunen
The hadroproduction of heavy-flavoured mesons has recently attracted a growing interest e.g. within the people involved in global analysis of proton and nuclear parton distribution…
Simulations of photo-nuclear dijets with Pythia 8 and their sensitivity to nuclear PDFs
Ilkka Helenius
In ultra-peripheral heavy-ion collisions the nuclei pass with such a large impact parameter that no strong interaction can take place. However, a photon emitted by one nucleus can…
Revisiting the D-meson hadroproduction in general-mass variable flavour number scheme
Ilkka Helenius, Hannu Paukkunen
We introduce a novel realization of the open heavy-flavour hadroproduction in general-mass variable flavour number scheme at next-to-leading order in perturbative QCD. The principa…
Photon-photon and photon-hadron processes in Pythia 8
Ilkka Helenius
We present a new implementation of photoproduction processes in e+e- and ep collisions into Pythia 8 Monte-Carlo event-generator. In particular we discuss how the parton showers an…