Raymond Ehlers

San Francisco Bay Area

I’m a researcher and scientist with interests in AI/ML, statistical methods (Bayesian inference), software, high-performance (scientific) computing, and data analysis. I’m currently looking for computation/engineering/research scientist roles in AI/ML for science.

Previously, my research studied the forces that hold matter together and the physics of the early universe about 1 microsecond after the big bang via high-energy collisions of nuclei, sometimes described as “little bangs”, at the Large Hadron Collider at CERN in Geneva, Switzerland.

More specifically, I’ve been an experimental physicist with a focus on studying high momentum transfer processes known as jets, with a particular interest in jet substructure. These jets are used as calibrated probes to study quantum chromodynamics (QCD) and the quark-gluon plasma (QGP) formed in heavy-ion collisions. My main research activities included experimentally measuring jet observables as a member of the ALICE (A Large Ion Collider Experiment) collaboration, as well as using these measurements to perform rigorous extractions of fundamental physics parameters via statistical methods (ie. Bayesian inference) as a member of the JETSCAPE collaboration.

news

Sep 04, 2025	Search for quasi-particle scattering with jet substructure published in PRL
Aug 01, 2025	Moving to new problems in industry!
May 16, 2025	Presented pair of virtual seminars at CTMP
Sep 19, 2024	New paper searching for Moliere scattering with jet substructure
Sep 15, 2024	Delivering plenary talk at Hard Probes 2024

latest posts

May 19, 2025	Setting up your software environment: 2025 edition
May 15, 2025	Strong showing from ALICE Jet Working Group at Quark Matter 2025
Feb 27, 2024	A first exercise with jet finding code

selected publications

VarP-GP: cost-efficient Bayesian emulation of quark-gluon plasma modeling with variable statistical precision

R. Ehlers, Y. Ji , et al.

Mar 2026

arXiv InspireHEP Bib

@article{Ehlers:2026yhq,
  author = {Ehlers, R. and Ji, Y. and Jacobs, P. M. and Mak, S.},
  title = {VarP-GP: cost-efficient Bayesian emulation of quark-gluon plasma modeling with variable statistical precision},
  eprint = {2603.05545},
  archiveprefix = {arXiv},
  primaryclass = {nucl-th},
  month = mar,
  year = {2026},
  inspire = {3127239},
}

Search for Quasiparticle Scattering in the Quark-Gluon Plasma with Jet Splittings in pp and Pb\(-\)Pb Collisions at \(\sqrt{s_{\rm NN}}\) = 5.02 TeV

ALICE Collaboration, Shreyasi Acharya, Apar Agarwal , et al.

Phys. Rev. Lett., Jul 2025

arXiv InspireHEP Bib

@article{ALICE:2024fip,
  author = {Acharya, Shreyasi and Agarwal, Apar and others},
  collaboration = {ALICE},
  title = {Search for Quasiparticle Scattering in the Quark-Gluon Plasma with Jet Splittings in pp and Pb\(-\)Pb Collisions at \(\sqrt{s_{\rm NN}}\) = 5.02 TeV},
  eprint = {2409.12837},
  archiveprefix = {arXiv},
  primaryclass = {nucl-ex},
  reportnumber = {CERN-EP-2024-238},
  doi = {10.1103/PhysRevLett.135.031901},
  journal = {Phys. Rev. Lett.},
  volume = {135},
  number = {3},
  pages = {031901},
  month = jul,
  year = {2025},
  inspire = {2831271},
}

Bayesian inference analysis of jet quenching using inclusive jet and hadron suppression measurements

JETSCAPE Collaboration, Raymond Ehlers, Yi Chen , et al.

Phys. Rev. C, May 2025

arXiv InspireHEP Bib

@article{JETSCAPE:2024cqe,
  author = {Ehlers, Raymond and Chen, Yi and others},
  collaboration = {JETSCAPE},
  title = {Bayesian inference analysis of jet quenching using inclusive jet and hadron suppression measurements},
  eprint = {2408.08247},
  archiveprefix = {arXiv},
  primaryclass = {hep-ph},
  doi = {10.1103/PhysRevC.111.054913},
  journal = {Phys. Rev. C},
  volume = {111},
  number = {5},
  pages = {054913},
  year = {2025},
  month = may,
  inspire = {2818238},
}

Measurement of the radius dependence of charged-particle jet suppression in Pb-Pb collisions at \(\sqrt{s_{\mathrm{NN}}}=5.02\) TeV

ALICE Collaboration, Shreyasi Acharya, Dagmar Adamova , et al.

Phys. Lett. B, Feb 2024

arXiv InspireHEP Bib

@article{ALICE:2023waz,
  author = {Acharya, Shreyasi and Adamova, Dagmar and others},
  collaboration = {ALICE},
  title = {Measurement of the radius dependence of charged-particle jet suppression in Pb-Pb collisions at \(\sqrt{s_{\mathrm{NN}}}=5.02\) TeV},
  eprint = {2303.00592},
  archiveprefix = {arXiv},
  primaryclass = {nucl-ex},
  reportnumber = {CERN-EP-2023-027},
  doi = {10.1016/j.physletb.2023.138412},
  journal = {Phys. Lett. B},
  volume = {849},
  pages = {138412},
  month = feb,
  year = {2024},
  inspire = {2637686},
}