Natural Units
Natural Units
Our universe is governed by a handful of fundamental constants, such as the speed of light or the gravitational constant. In particle physics, it is often convenient to use natural units, in which key constants are set to unity, revealing the underlying simplicity of physical laws.
2025 Thesis Award Winners
The ATLAS Thesis Award winners for 2025 are:
- Takumi Aoki (University of Tokyo, Japan): Search for the Slepton Cascade Decay using Final States with Opposite or Same Sign Three Leptons in the LHC-ATLAS experiment
- Kartik Deepak Bhide (Albert-Ludwigs-Universität Freiburg, Germany): Illuminating the tau lepton with the ATLAS detector: A study of ɣɣ→ττ scattering in ultra-peripheral Pb+Pb collisions, and constraints on the tau lepton electromagnetic dipole moments
- Antonio Jesús Gómez Delegido (Universitat de València, Spain): Unveiling the Higgs sector with tau-leptons: differential cross-section measurements and searches for lepton-flavor-violating decays with the ATLAS detector
- Simon Florian Koch (University of Oxford, UK): Measurements of ATLAS, measurements with ATLAS: Construction and characterisation of ITk Pixel detector structures, and a search for leptoquarks in events with di-tau final states
- Elena Mazzeo (Università degli studi di Milano, Italy): Shedding light on Higgs boson self-interactions in the bbɣɣ channel. Photon and b-jet calibrations, and searches for Higgs boson pairs with the ATLAS experiment
- Ryan Roberts (University of California, Berkeley and Lawrence Berkeley National Laboratory, USA): Observation of Four-Top Quark Production and Measurement of Off-shell Higgs Boson Interactions with Top Quarks with ATLAS
- Stephen Nicholas Swatman (University of Amsterdam, Netherlands): Charged Particle Track Reconstruction Algorithms for Massively Parallel Systems
- Elliot Watton (University of Glasgow and Rutherford Appleton Laboratory, UK): Measurement of the top-quark mass with the ATLAS detector using ttbar events with a boosted top quark
See the News Article on the 2025 Awards.
ATLAS Open Virtual Visit
Join us for an Open ATLAS Virtual Visit, hosted by ATLAS physicists Christian Appelt and Despoina Sampsonidou.
This live virtual event will take you inside the ATLAS cavern at CERN, offering a rare opportunity to see the ATLAS detector up close before the cavern is closed for LHC operation. From 100 meters underground, the hosts will guide you around one of the world’s largest and most sophisticated scientific instruments.
Pile-Up
Pile-Up
The LHC collides bunches (groups of protons), which can result in multiple proton-proton collisions at each crossing. Such additional collisions are called pile-up.
ATLAS Coordinate System
ATLAS Coordinate System
The ATLAS coordinate system allows scientists to accurately and consistently describe how particles travel through the detector.
2025 Outstanding Achievement Award Winners
The ATLAS Outstanding Achievement Award winners for 2025 are:
- Masato Aoki (KEK), Leesa Brown (Victoria and TRIUMF), George Chatzianastasiou (CERN and BNL), Thiago Costa de Paiva (University of Massachusetts Amherst)(not pictured), Nathan Felt (Harvard)(not pictured), Simone Francescato (Harvard), Eleni Kanellaki (Demokritos)(not pictured), Foteini Kolitsi (uniWA), Audrey Kvam (University of Massachusetts Amherst), Callum McCracken (Vancouver UBC and TRIUMF), Tomoyuki Saito (Tokyo ICEPP), Yoshiaki Tsujikawa (Kyoto) for the deployment of the complete Phase-I L1 Muon Endcap Trigger, including the NSW triggers, enabling ATLAS to run at higher pileup and gather more data in 2024.
- Doug Benjamin (Brookhaven BNL)(not pictured), Andrej Filipcic (Jozef Stefan Institute, Ljubljana)(not pictured), Michal Svatos (Prague AS), Rod Walker (Munich LMU)(not pictured) for advancing the experiment’s computing infrastructure through the integration of HPCs, which contribute substantially to ATLAS’s Run 3 computing power.
- Brian Andrew Cole (Columbia), Riccardo Longo (Urbana UI) for contributing to the installation, commissioning and operation of the ZDC detector and responding to multiple challenges in November 2024.
- Bojan Hiti (Jozef Stefan Institute, Ljubljana)(not pictured), Alissa Howard (Jozef Stefan Institute, Ljubljana)(not pictured), Xuewei Jia (Beijing IHEP), Mengzhao Li (Beijing IHEP)(not pictured), Chihao Li (CERN), Kuo Ma (USTC)(not pictured), Theodoros Manoussos (CERN), Weiyi Sun (IHEP CAS), Guilherme Tomio Saito (Universidade de São Paulo), Iskra Velkovska (Jozef Stefan Institute, Ljubljana), Xiao Yang (USTC)(not pictured), Mei Zhao (Beijing IHEP)(not pictured) for the successful design and testing campaign of the HGTD LGAD sensors that led to the start of sensor production.
- Tobias Bisanz (Dortmund) for management of pixel code and databases, improving reliability and speed of detector calibrations, contributions to operations, and substantial improvements to system stability and monitoring in 2024.
- André Rummler (CERN) for years of exceptional management of ATLAS operations, including significant interventions in 2024 to manage the recovery of the ATLAS infrastructure in the face of cooling challenges, enabling excellent data-taking efficiency.
- Huacheng Cai (Pittsburgh), Etienne Fortin (CERN)(not pictured), Davide Mungo (Toronto), Pavol Strizenec (Kosice)(not pictured) for successful operation of the LAr detector, including contributions to online software and detector control systems, while commissioning the digital trigger.
See the News Article on the 2025 Awards