About Me

I’m a senior researcher (Akademischer Rat) at University of Bielefeld, Germany. I work on theoretical physics, mainly on high energy nuclear physics. My work revolves around Quantum Chromodynamics (QCD), and its application to heavy ion collisions at RHIC and LHC.

Research Focus

My research focuses on understanding the properties of the quark-gluon plasma (QGP), a state of matter that existed shortly after the Big Bang. I study jets—highly energetic particles created at the early stages of heavy ion collisions—as tomographic probes of the QGP. These jets traverse the medium and lose energy through interactions, a phenomenon known as jet quenching, allowing us to extract fundamental properties such as transport coefficients.

Hard-Soft Correlations

**Fig (a):** Jets in Heavy Ion Collisions: Jets lose energy traversing the QGP, acting as tomographic probes.

A central theme of my work is understanding the interplay between hard partons (jets) and soft particles (the QGP medium). In heavy-ion collisions, energetic jets modify the surrounding medium, creating observable wakes and collective responses [29]. In small collision systems (pp, p-Pb), jets carry a substantial fraction of the total energy, making these correlations essential for distinguishing initial-state effects from final-state interactions [6].

Theoretical Methods

I develop and apply effective kinetic theory frameworks to describe jet-medium interactions:

AMY kinetic theory: Modeling jet evolution in evolving QGP backgrounds, capturing jet thermalization [29,35,36]
BDMPS-Z formalism: Computing medium-induced radiation including LPM interference effects [12,31,34]
TMD distributions: Understanding transverse momentum correlations in small systems through parton distribution and fragmentation functions [7,20]

Collaborations

I am an active member of major international collaborations studying QCD matter:

CRC-TR 211: Collaborative Research Center on "Strong-interaction matter under extreme conditions" (Germany)
Centre of Excellence in Quark Matter: Finnish center of excellence studying the theory of hot QCD matter (University of Jyväskylä)
JETSCAPE Collaboration: Developing a comprehensive software framework for simulating jet propagation through the QGP
YoctoLHC: Exploring The Formation of the Primordial State of Matter in the Universe

Publications

[1]

I. Soudi and A. Takacs, Deriving a parton shower for jet thermalization in QCD plasmas, (2025).

[2]

H. Roch et al., Transport-based initial conditions for heavy-ion collisions at finite densities, (2025).

[3]

Y. Tachibana et al., Enhanced signal of momentum broadening in hard splittings for γ-tagged jets in a multistage approach, (2025).

[4]

A. Sengupta et al., Hybrid Hadronization – A Study of In-Medium Hadronization of Jets, (2025).

[5]

R. Ehlers et al., Bayesian inference analysis of jet quenching using inclusive jet and hadron suppression measurements, Phys. Rev. C 111, 054913 (2025).

[6]

I. Soudi et al., Soft-hard framework with exact four-momentum conservation for small systems, Phys. Rev. C 112, 014905 (2025).

[7]

I. Soudi and A. Majumder, T-odd parton distribution functions and azimuthal anisotropy at high transverse momentum in p-p and p-A collisions, Phys. Rev. C 111, 024901 (2025).

[8]

C. Sirimanna et al., Interplay of prompt and non-prompt photons in photon-triggered jet observables, EPJ Web Conf. 339, 05002 (2025).

[9]

H. Roch et al., Effects of hadronic reinteraction on jet fragmentation from small to large systems, EPJ Web Conf. 339, 02017 (2025).

[10]

I. Soudi, Jets: Hard-soft correlation - Theory overview, EPJ Web Conf. 339, 01002 (2025).

[11]

C. Sirimanna et al., Hard-photon-triggered jets in p-p and A-A collisions, Phys. Rev. C 111, 064911 (2025).

[12]

I. Soudi, Medium-induced parton splitting in expanding QCD matter, (2024).

[13]

I. Soudi and A. Majumder, Studying high p_T momentum azimuthal anisotropies in unpolarized proton-proton collisions using transverse momentum dependent (TMD) parton distribution and fragmentation functions, PoS SPIN2023, 164 (2024).

[14]

C. Sirimanna et al., Photon-triggered jets as probes of multi-stage jet modification, EPJ Web Conf. 296, 11008 (2024).

[15]

S. Cao, A. Majumder, R. Modarresi-Yazdi, I. Soudi, and Y. Tachibana, Jet quenching: From theory to simulation, Int. J. Mod. Phys. E 33, 2430002 (2024).

[16]

R. Ehlers et al., Measuring jet quenching with a Bayesian inference analysis of hadron and jet data by JETSCAPE, EPJ Web Conf. 296, 15009 (2024).

[17]

I. Soudi and A. Majumder, Azimuthal anisotropies at high-p_T from transverse momentum dependent (TMD) parton distribution and fragmentation functions, EPJ Web Conf. 296, 13015 (2024).

[18]

A. Mankolli et al., 3D multi-system Bayesian calibration with energy conservation to study rapidity-dependent dynamics of nuclear collisions, EPJ Web Conf. 296, 05010 (2024).

[19]

A. Angerami et al., Hybrid Hadronization of Jet Showers from e⁺ + 𝑒⁻ to 𝐴 + 𝐴 with JETSCAPE, PoS HardProbes2023, 166 (2024).

[20]

I. Soudi and A. Majumder, Azimuthal anisotropy at high transverse momentum in p-p and p-A collisions, Phys. Lett. B 859, 139105 (2024).

[21]

Jetscape et al., A multistage framework for studying the evolution of jets and high-pT probes in small collision systems, PoS HardProbes2023, 128 (2024).

[22]

Jetscape et al., Multiscale evolution of heavy flavor in the QGP, PoS HardProbes2023, 100 (2024).

[23]

W. Fan et al., New metric improving Bayesian calibration of a multistage approach studying hadron and inclusive jet suppression, Phys. Rev. C 109, 064903 (2024).

[24]

Jetscape et al., Effects of multi-scale jet-medium interactions on jet substructures, PoS HardProbes2023, 165 (2024).

[25]

Y. Tachibana et al., Hard jet substructure in a multistage approach, Phys. Rev. C 110, 044907 (2024).

[26]

M. Arslandok et al., Hot QCD White Paper, (2023).

[27]

J. H. Weber, A. Kumar, A. Majumder, and I. Soudi, Computing jet transport coefficients on the lattice, PoS HardProbes2023, 180 (2023).

[28]

C. Sirimanna, I. Soudi, G. Vujanovic, W.-J. Xing, S. Cao, and A. Majumder, Quenching jets increases their flavor, Phys. Rev. C 108, 014911 (2023).

[29]

Y. Mehtar-Tani, S. Schlichting, and I. Soudi, Jet thermalization in QCD kinetic theory, JHEP 05, 091 (2023).

[30]

W. Fan et al., Multiscale evolution of charmed particles in a nuclear medium, Phys. Rev. C 107, 054901 (2023).

[31]

S. Schlichting and I. Soudi, Non-perturbative Determination of the Collisional Broadening Kernel and Medium-induced Radiation in QCD Plasmas, Acta Phys. Polon. Supp. 16, 1 (2023).

[32]

G. D. Moore, S. Schlichting, N. Schlusser, and I. Soudi, Non-perturbative phenomena in jet modification, EPJ Web Conf. 258, 05001 (2022).

[33]

I. Soudi, Energy loss and equilibration of a highly energetic parton in QCD plasmas, PhD thesis, Bielefeld U., 2021.

[34]

G. D. Moore, S. Schlichting, N. Schlusser, and I. Soudi, Non-perturbative determination of collisional broadening and medium induced radiation in QCD plasmas, JHEP 10, 059 (2021).

[35]

S. Schlichting and I. Soudi, Energy loss and equilibration of jets in a QCD plasma., PoS HardProbes2020, 137 (2021).

[36]

S. Schlichting and I. Soudi, Medium-induced fragmentation and equilibration of highly energetic partons, JHEP 07, 077 (2021).

[37]

I. Soudi, G. Farrugia, V. Gakis, J. Levi Said, and E. N. Saridakis, Polarization of gravitational waves in symmetric teleparallel theories of gravity and their modifications, Phys. Rev. D 100, 044008 (2019).