Ben Carlson

  • Adjunct Assistant Professor



Ben Carlson is currently an assistant professor at Westmont College where he continues to collaborate with the University of Pittsburgh ATLAS group.

Until 2021, he was a Samuel Langely fellow and Postdoctoral Associate at the University of Pittsburgh.  He attend graduate school at Carnegie Mellon University and received a Ph.D. in 2015. He joined the CMS experiment, where he worked on a measurement of the Upsilon cross section and a search for supersymmetry. His thesis was on a search for “stealth” supersymmetry using leptons and jets and no missing transverse energy. From 2014-2015, Ben was based at Fermilab, supported by awards from the Universities Research Association and the LHC Center for Physics. As an undergraduate REU student, Ben studied electron cloud development at the Cornell Electron Storage Ring.


Ben's current physics interest is searching for beyond the standard model decays of the Higgs boson. He is currently working on searches for decays of the Higgs boson that including missing transverse momentum. Ben also works on the ATLAS trigger system, particularly the missing transverse energy signature, a task vital to the invisible Higgs search. He is working on techniques to mitigate the impact of pileup on the trigger rates at both L1 and the HLT. He was co-coordinator of the ATLAS missing transverse momentum subgroup from 2020-2022.

Ben has a keen interest in the long-term future of the LHC projects. In particular, he is working on the ATLAS detector design for the planned detector upgrades. In 2016, Ben coordinated all of the Monte Carlo simulations for ATLAS upgrade studies. He was is co-coordinator of the L1 algorithm and trigger performance forum from 2016-2020. This group is responsible for optimizing the performance of the L1 calorimeter trigger system for the ATLAS upgrade scheduled to be installed before the next run of the LHC.

Selected Publications

  • Stephen Roche, Quincy Bayer, Benjamin Carlson, William Ouligian, Pavel Serhiayenka, Joerg Stelzer, Tae Min Hong, “Nanosecond anomaly detection with decision trees for high energy physics and real-time application to exotic Higgs decays,” submitted (2023). arXiv: 2304.03836.
  • B. T. Carlson, Q. Bayer, T.M. Hong, S.T. Roche, “Nanosecond machine learning regression with deep boosted decision trees in FPGA for high energy physics,” Journal of Instrumentation 17 P09039 (2022). arXiv: 2207.05602.
  • ATLAS Collaboration, “Search for invisible Higgs-boson decays in events with vector-boson fusion signatures using 139 fb-1 of proton-proton data recorded by the ATLAS experiment,” Journal of High Energy Physics 08 (2022) 104. arXiv: 2202.07953.
  • Benjamin Carlson, Tao Han, Sze Ching Iris Leung, “Higgs to charm quarks in vector boson fusion plus a photon,” Phys. Rev. D 104 073006 (2021). arXiv: 2105.08738.
  • ATLAS Collaboration, “Observation of electroweak production of two jets in association with an isolated photon and missing transverse momentum, and search for a Higgs boson decaying to invisible particles at 13 TeV with the ATLAS detector,” The European Physical Journal C 82 105 (2022). arXiv: 2109.00925
  • ATLAS Collaboration, Performance of the ATLAS Level-1 topological trigger in Run 2, The European Physical Journal C 82 7 (2022). arXiv: 2105.01416.
  • Tae Min Hong, Benjamin Carlson, Brandon Eubanks, Stephen Racz, Stephen Roche, Joerg Stelzer, Daniel Stumpp, Nanosecond machine learning event classification with boosted decision trees in FPGA for high energy physics, Journal of Instrumentation 16 P08016 (2021). arXiv: 2104.03408.
  • ATLAS Collaboration, Performance of the missing transverse momentum triggers for the ATLAS detector during Run-2 data taking, JHEP 2020 (080) (2020). arXiv: 2005.09554
  • ATLAS Collaboration, Performance of the upgraded PreProcessor of the ATLAS Level-1 Calorimeter Trigger, JINST 15 (2020) P11016. arXiv: 2005.04179
  • ATLAS Collaboration, Searches for electroweak production of supersymmetric particles with compressed mass spectra in sqrt(s) = 13 TeV pp collisions with the ATLAS detector, Phys. Rev. D 101, 052005 (2020). arXiv: 1911.12606
  • ATLAS Collaboration, Combination of searches for invisible Higgs boson decays with the ATLAS experiment, Phys. Rev. Lett. 122, 231801 (2019). arXiv: 1904.05105
  • ATLAS Collaboration, Search for invisible Higgs boson decays in vector boson fusion at sqrt(s) = 13 TeV with the ATLAS detector, Phys. Lett. B 793 499-519 (2019). arXiv: 1809.06682
  • CMS Collaboration, Search for R-parity violating decays of a top squark in proton–proton collisions at sqrt(s) = 8 TeV, Phys. Lett. B. 760, 178 (2016). arXiv: 1602.04334
  • CMS Collaboration, Measurements of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) differential cross sections in pp collisions at sqrt(s) = 7 TeV, Phys. Lett. B 749, 14 (2015). arXiv:1501.07750
  • CMS Collaboration, Search for supersymmetry in events with jets, either photons or leptons, and low missing transverse momentum in pp collisions at 8 TeV, Phys. Lett. B, 743, 503 (2015). arXiv:1411.7255
  • J.P Sikora, B.T. Carlson, D.O. Duggins, K.C Hammond, S.D Santis, A.J. Tencate, Electron cloud density measurements in accelerator beam-pipe using resonant microwave excitation, Nucl. Instrum. Methods Phys. Res., Sect. A , 754, 28-25 (2014). arXiv:1311.5633
  • S. De Santis, J.M. Byrd, M.G. Billing, M.A. Palmer, J.P. Sikora, B.T. Carlson, Characterization of electron clouds in the Cornell Electron Storage Ring Test Accelerator using TE-wave transmission,  Phys. Rev. ST Accel. Beams, 13, 071002 (2010).

Faculty Advisor

Tae Min Hong