The DiPetrillo Lab


Our goal is to understand the fundamental particles and forces that make up the universe. Our work is based in Geneva, Switzerland at the Large Hadron Collider (LHC), where we study the highest energy particle collisions ever produced in a laboratory. We collaborate with thousands of physicists from across the globe on operating and upgrading the ATLAS Experiment, a massive detector designed to reconstruct the byproducts of LHC collisions. We use the resulting data to characterize known particles with unprecedented precision and to search for evidence of new fundamental particles.

Current Projects



Long-lived particles

Particles with intermediate lifetimes are predicted in a variety of compelling dark matter, Supersymmetry, and hidden valley models. These new particles would decay a significant distance from the collision point, resulting in displaced or anomalous tracks, and pose tremendous challenges for ATLAS and CMS.

Dark Sectors

Dark matter particles might be part of a complex hidden sector. These scenarios can result in a wide variety of unusual signatures at the LHC. We're particularly interested in dark QCD scenarios that could result in highly unusual jets and soft-unclustered energy patterns

Track-based Triggers

The ATLAS trigger system rapidly decides in real time which of the <0.01% of LHC events we can save for analysis, and which events are lost forever. Currently there's no way to trigger directly on events with unusual track signatures, but this picture will change in the future. We're working on new track-based triggers for exotic scenarios.


HL-LHC Tracker Upgrade

ATLAS is building a completely new Inner Detector called the Inner Tracker (ITK) to disentangle the higher rate of collisions expected at the High-Luminosity LHC. The ITk will be a fully-silicon detector covering twice as much area as the current tracker, with 50 times more readout channels.

Tracker R&D

Future colliders call for cutting-edge silicon pixel detectors with entirely new capabilities. The next trackers must be 4D, low mass, radiation hard, and intelligent. We're developing several flavors of CMOS pixel sensors as candidates for future e+e- colliders as well as smart pixel detectors for future discovery machines.

Future Colliders

A 10 TeV Muon Collider offers a path to similar physics as a 100 TeV proton collider, with a much smaller footprint and lower energy consumption. The trade-offs are the technical challenges posed by the muon's lifetime. Recent progress in overcoming these challenges has generated a great deal of excitement for particle physicists.

Recent Talks


Future Colliders: Outcomes from Snowmass & Options for the US @Vietnam

Searches for long-lived particles at the LHC @Aspen

Off the Beaten Track: Unconventional Searches at the LHC @UChicago Rising Stars

CMS in 10 minutes @New Perspectives

Searches for long-lived particles with the CMS experiment @DPF

CMS Endcap Timing Layer for the HL-LHC @ICHEP

ATLAS search for SUSY in events with a displaced vertex and muon @Moriond

Searches for long-lived Supersymmetry in ATLAS @Rencontres du Vietnam

Overview of ATLAS long-lived particle searches @ICTP

Publications


Search for soft unclustered energy patterns in proton-proton collisions at 13 TeV CMS-PAS-EXO-23-002

Smart pixel sensors: towards on-sensor filtering of pixel clusters with deep learning arXiv:2310.02474

Search for heavy, long lived charged particles with large specific ionisation and low-beta at 13 TeV with ATLAS ATLAS-CONF-2023-044

ATLAS Detector Configuration for Run 3 arXiv:2305.16623

Search for long-lived particles in events with a displaced vertex and multiple jets at 13 TeV with ATLAS arXiv:2301.13866

Optimizing Trigger-Level Track Reconstruction for Sensitivity to Exotic Signatures arXiv:2211.05720

Report of the Topical Group on Physics Beyond the Standard Model at Energy Frontier for Snowmass 2021 arXiv:2209.13128

Muon Collider Forum Report arXiv:2209.01318

Report of the Topical Group on Solid State Detectors and Tracking for Snowmass 2021 arXiv:2209.03607

Theory, phenomenology, and experimental avenues for dark showers arXiv:2203.09503

Track-Based Triggers for Exotic Signatures arxiv:2203.07314

Review of opportunities for long-lived particle triggers in Run 3 of the LHC arXiv:2110.14675

Combined analysis of HPK 3.1 LGADs using a proton beam, beta source, and probe station arXiv:2104.08369

Resistive AC-Coupled Silicon Detectors: principles of operation and first beam test and laser data arXiv:2007.09528

Observation of the production of three massive bosons at 13 TeV with CMS arXiv:2006.11191

Measurements of an AC-LGAD strip sensor with a 120 GeV proton beam arXiv:2006.01999

Search for long-lived particles in events with a displaced vertex and a muon at 13 TeV with ATLAS arXiv:2003.11956

ATLAS data quality operations and performance for 2015–2018 data-taking arXiv:1911.04632

Displaced vertex reconstruction performance for long-lived particle searches using the ATLAS Inner Detector ATL-PHYS-PUB-2019-013

H→WW*→eνμν cross-section measurements at 13 TeV with ATLAS arXiv:1808.09054

Reinterpretation of prompt Supersymmetry searches in models long-lived particles ATLAS-CONF-2018-003

Search for long-lived particles in events with a displaced vertex and missing transverse momentum at 13 TeV with ATLAS arXiv:1710.04901

Z + jets cross section measurements at 13 TeV with ATLAS arXiv:1702.05725

Contact Us


We're part of the UChicago ATLAS group at the University of Chicago's Enrico Fermi Institute.

We are always looking for new undergraduates, graduate students, and postdocs! Contact Karri (karri@uchicago.edu) if you're interested in joining.

Office: Michelson Center for Physics 229