# Christos Leonidopoulos

### Dr C Leonidopoulos

Position
Category
Location
James Clerk Maxwell Building (JCMB)
Room 5415

Christos is a member of the following School research institute, research group and research areas:

### Research interests

Christos Leonidopoulos is a Chancellor's Fellow and a Reader at the University of Edinburgh.

He received his PhD from Princeton University in 2000, working on Bd mixing and CPT violation searches with the Belle experiment at KEK, Japan. In his thesis he carried out the first experimental test of CPT symmetry in the Bd system and produced the most precise mixing measurement in the world at the time [Int. J. Mod. Phys. A16S1A, 401-403 (2001) and Phys.Rev.Lett. 86 (2001) 3228, a paper with 142 citations].

He then worked on Bd and Bs mixing with the D0 experiment at Fermilab, Chicago as a Research Associate with Columbia University [Phys.Rev.Lett.97:241801 (2006), a paper with 49 citations and Phys.Rev.Lett. 97 (2006) 021802, a paper with 339 citations]. In parallel, he led the integration and commissioning of the Level-2 muon trigger [Nucl.Instrum.Meth. A565 (2006) 463-537].

He moved to Geneva, Switzerland in 2004 as Research Physics Staff with CERN where he worked on building the CMS experiment, and in particular on the design, implementation and commissioning of a novel triggering system known as the High Level Trigger [CERN/LHCC 2007-021, LHCC-G-134 (2007)J.Phys.G34:995-1579 (2007)JINST 0803:S08004 (2008) and JINST 5:T03005 (2010)]. He served as the Deputy Trigger Coordinator for the startup of the LHC and for four years.

In 2011 he received an LPC Fellowship by Fermilab during which he implemented with his team a program of generic searches for new heavy charged bosons, producing the most stringent exclusion limits in the world in several final states [Phys. Lett. B701, 160–179 (2011): a paper with 43 citations, JHEP 08 (2012) 023: a paper with 72 citations, Phys. Rev. Lett. 109, 141801 (2012): a paper with 38 citations, and JHEP 02 (2013) 036, a paper with 20 citations]. His involvement with CMS culminated with the discovery of the Higgs boson [Phys.Lett. B716 (2012) 30-61, a paper with 4200+ citations].

He moved to Edinburgh in 2012 with a Chancellor's Fellowship and joined the ATLAS experiment. He worked on the measurement of the Higgs boson properties [Phys. Rev. D 91, 012006 (2015): a paper with 52 citations, and Phys. Rev. D. 90, 052004 (2014): a paper with 157 citations.]

He currently serves as the Online software and computing (WG10) Convener for the FCC-ee/TLEP concept study [JHEP01(2014)164: a paper with 118 citations].

His general research interests lie in the Electroweak Symmetry-Breaking mechanism, in Exotic physics searches at the LHC, and in triggers. In the next years, together with his research team, he will be focussing on searches for new exotic particles and upgrades of the High-Level Trigger for the ATLAS experiment at the LHC.

### Websites

Additional information can be found at his personal page.

Higgs Massive Open Online Course (MOOC)

• Overall coordination and design of the course (with Prof. Luigi Del Debbio)
• Development of lecture discussing the experimental aspects of the discovery of the Higgs boson.

Launch dates:

• 10 February 2014
• 26 January 2015
• 8 February 2016

https://www.futurelearn.com/courses/higgs

Collider Physics

• Post-graduate course with the Scottish Universities Physics Alliance (Spring); Emphasis given on recent experimental resuls & papers
• 2013, 2014, 2015, 2016

Relativity, Nuclear and Particle Physics (PHYS10096)

• "Particle Physics" component with lectures & tutorials (Autumn); Emphasis given on recent experimental resuls & papers
• 2014, 2015

#### Exotic Particles Discoveries at Colliders

In this video Christos describes his research with the ATLAS experiment: The discovery of the Higgs boson, the search for new Exotic Particles and the quest to understand what the Universe is made of.

### Recent publications

1. Search for heavy long-lived charged $R$-hadrons with the ATLAS detector in 3.2 fb$^{-1}$ of proton--proton collision data at $\sqrt{s} = 13$ TeV DOI
, , , , , , , , , , , et al., Physics Letters B, B760, p. 647-665
2. Search for TeV-scale gravity signatures in high-mass final states with leptons and jets with the ATLAS detector at $\sqrt{s}=13$ TeV DOI
, , , , , , , , , , , et al., Physics Letters B, B760, p. 520-537
3. Measurement of $W^{\pm}$ and $Z$-boson production cross sections in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector DOI
, , , , , , , , , , , et al., Physics Letters B, B759, p. 601-621
4. Search for charged Higgs bosons produced in association with a top quark and decaying via $H^{\pm} \rightarrow \tau\nu$ using $pp$ collision data recorded at $\sqrt{s} = 13$ TeV by the ATLAS detector DOI
, , , , , , , , , , , et al., Physics Letters B, B759, p. 555-574
5. Search for resonances in the mass distribution of jet pairs with one or two jets identified as $b$-jets in proton--proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector DOI
, , , , , , , , , , , et al., Physics Letters B, B759, p. 229-246