C. Andres, J. Holguin, B. Kimelman, R. Kunnawalkam Elayavalli, J. Viinikainen, Z. Yang, "Living on the edge: radius effects in the angular substructure of heavy-ion jets", arXiv:2512.10026
CV
Education
- Doctor of Philosophy in physics, University of Jyväskylä, 2017
- Specialization in experimental high energy heavy ion physics
- Link to my PhD thesis
- Master of Science in theoretical physics, University of Jyväskylä, 2012
- Minor: French language and culture
- Link to my master’s thesis
- Bachelor of Science in physics, University of Jyväskylä, 2010
- Minors: Mathematics and computer science
Work experience
- January 2022 - Current: Postdoctoral researcher
- Vanderbilt University
- Nashville, Tennessee, USA
- Duties include:
- Analysis on energy-energy correlators
- Analysis on dijet azimuthal asymmetry
- Convener of the high \(p_{\mathrm{T}}\) physics interest group within the CMS heavy ion group
- Producing rapid validation datasets during the 2023 heavy ion run
- Maintaining the common analysis code (HiForest) for the CMS heavy ion group
- Helping to supervise students
- Supervisors: Julia Velkovska and Raghav Kunnawalkam Elayavalli
- March 2018 - September 2021: Postdoctoral researcher
- University of Illinois at Chicago
- Chicago, Illinois, USA
- Duties included:
- Analysis on jet shapes from dijet events
- Analysis on dijet azimuthal asymmetry
- Control room shifts in the CMS experiment
- Alignment validation for tracker during 2018 heavy ion run
- Updating alignment validation tool to include a tracker validation method for high \(p_{\mathrm{T}}\) tracks
- Supervisor: Olga Evdokimov
- November 2012 - December 2017: PhD Student
- University of Jyväskylä
- Jyväskylä, Finland and CERN, Switzerland/France
- Duties included:
- Analysis on jet fragmentation transverse momentum
- Run manager for the ALICE experiment for one month
- Updating the firmware in the EMCal trigger for run2
- Control room shifts at the ALICE experiment
- Being teaching assistant in particle physics and heavy ion physics courses
- Supervisors
- Main: Jan Rak
- Helping: Sami Räsänen and Dong Jo Kim
- June 2008 - August 2008: Summer intern
- Stresstech Oy
- Vaajakoski, Finland
- Duties included measuring residual stresses from metal pieces
Publications
Below you can find selected articles in which I have been the main analyzer. You can find the full list of articles I am on the author list on my InspireHEP page.
Journal articles
CMS Collaboration, "Observation of nuclear modification of energy-energy correlators inside jets in heavy ion collisions", Phys. Lett. B 866 (2025) 139556 [2503.19993]
C. Andres, J. Holguin, R. Kunnawalkam Elayavalli, J. Viinikainen, "Minimizing selection bias in inclusive jets in heavy-ion collisions with energy correlators", Phys. Rev. Lett. 134 (2025) 8, 082303 [2409.07514]
CMS Collaboration, "Azimuthal anisotropy of dijet events in PbPb collisions at \(\sqrt{s_{\mathrm{NN}}} = \) 5.02 TeV", JHEP 07 (2023) 139 [2210.08325]
CMS Collaboration, "In-medium modification of dijets in PbPb collisions at \(\sqrt{s_{\mathrm{NN}}} = \) 5.02 TeV", JHEP 05 (2021) 116 [2101.04720]
ALICE Collaboration, "Jet fragmentation transverse momentum measurements from di-hadron correlations in \(\sqrt{s} = \) 7 TeV pp and \(\sqrt{s_{\mathrm{NN}}} = \) 5.02 TeV p-Pb collisions", JHEP 03 (2019) 169 [1811.09742]
Conference proceedings
J. Viinikainen for the CMS Collaboration, "Study of energy-energy correlator of jets in PbPb collisions at CMS", EPJ Web Conf. 339 (2025) 02007
J. Viinikainen for the CMS Collaboration, "Resolving medium properties using high-pT jets with jet and in-jet correlations in PbPb collisions at 5.02 TeV with the CMS detector", EPJ Web Conf. 296 (2024) 11010
J. Viinikainen for the CMS Collaboration, "Studies of in-medium modification of dijets in PbPb collisions at 5.02 TeV with the CMS detector", Acta Phys. Polon. Supp. 16 (2023) 1
J. Viinikainen for the CMS Collaboration, "Latest results on jet suppression and jet substructure in heavy-ion collisions with CMS", PoS LHCP2019 (2019) 219
J. Viinikainen for the ALICE Collaboration, "Jet transverse fragmentation momentum from h–h correlations in pp and p–Pb collisions", Nucl. Part. Phys. Proc. 289-290 (2017) 293 [1612.05475]
Talks
The first measurement of energy-energy correlator of jets in PbPb collisions at CMS
Parallel talk at Quark Matter 2025, Frankfurt, Germany
The first measurement of medium modification of energy-energy correlator
Invited talk at High-Energy Nuclear Physics in China, Online
What do we learn from the first EEC measurements in PbPb collisions by the CMS collaboration?
Talk at SoftJet 2024, Tokyo, Japan
Study of energy-energy correlator of jets in PbPb collisions at CMS
Parallel talk at Hard Probes 2024, Nagasaki, Japan
Energy-energy correlators from PbPb and pp collisions at 5.02 TeV with CMS
Invited talk at Energy Correlators at the Collider Frontier, Mainz, Germany
Experimental determination of energy-energy correlators in heavy ion collisions
Invited talk at Winter Workshop on Nuclear Dynamics 2024, Jackson, WY, USA
How to measure energy-energy correlators from heavy ion collisions
Talk at Probing QCD at High Energy and Density with Jets, Seattle, WA, USA
Resolving medium properties using high-pT jets with jet and in-jet correlations in PbPb collisions at 5.02 TeV with the CMS detector
Parallel talk at Quark Matter 2023, Houston, TX, USA
Recent jet substructure measurements in heavy-ion collisions with the CMS experiment
Talk at BOOST 2022, Hamburg, Germany
Studies of in-medium modification of dijets in PbPb collisions at 5.02 TeV with the CMS detector
Parallel talk at Quark Matter 2022, Krakow, Poland
Study of in-medium modification of dijets in PbPb collisions at 5.02 TeV with CMS
Talk at APS DNP Fall Meeting 2020, Online
Latest results on jet suppression and jet substructure in heavy-ion collisions with CMS
Parallel talk at LHCP 2019, Puebla, Mexico
Jets shapes in high energy heavy ion collisions with CMS
Seminar at Argonne National Laboratory Heavy ion discussion group, Lemont, IL, USA
Jet transverse fragmentation momentum from h-h correlations in pp and p-Pb collisions
Parallel talk at Hard Probes 2016, Wuhan, China
Jet fragmentation transverse momentum studies with ALICE
Talk at Finnish Particle Physics Days 2013, Helsinki, Finland
The first p-Pb measurements at \(\sqrt{s_{\mathrm{NN}}} = 5.02 \) TeV by ALICE
Talk at Annual meeting of the Finnish Physical Society 2013, Espoo, Finland
Study of the jet fragmentation with two particle correlations in Pb-Pb collisions at \(\sqrt{s_{\mathrm{NN}}} = 2.76 \) TeV by ALICE
Talk at Finnish Particle Physics Days 2012, Jyväskylä, Finland
Posters
Jet shapes, dijets and jet axes in CMS
Poster at Quark Matter 2019, Wuhan, China
Leadership experience and positions of trust
- September 2022 - September 2024: Convener of the high-\(p_{\mathrm{T}}\) physics interest group within the CMS heavy ion group
- April 2017 - May 2017: Run manager in the ALICE experiment, two weeks both in April and May
- October 2015 - March 2018: Junior ambassador of Finland in the ALICE experiment
- November 2012 - November 2014: President of the residents’ committee in at KOAS Ristonmaa student housing association
- September 2012 - November 2012: Member of the students’ union at the University of Jyväskylä
- November 2010 - November 2012: Member of the residents’ committee in at KOAS Ristonmaa student housing association
Community service
- June 2024: I was one of the organizers of the jet workshop during the 2024 RHIC/AGS users’ meeting.
Honors and awards
- 2013-2016: In each of these years, I got a grant worth 20 000 € to support my PhD studies from the Magnus Ehrnrooth foundation.
- March 2013: Best oral presentation award in the annual meeting of the Finnish Phyical Society.
Skills
- Languages (CEFR levels: A1 and A2: Basic user; B1 and B2: Independent user; C1 and C2: Proficient user)
- Finnish: Mother tongue
- English: C2
- French: B1
- Swedish: A2
- Programming languages
- C++ and root libraries
- Python
- bash
- Java
- Other digital skills
- Proficient user of LaTeX
- Experience in working with MacOS, Linux/Unix and Windows operating systems
- Experience with Git and GitHub