Experimental Particle Physics at the University of Edinburgh
Lead Research Organisation:
University of Edinburgh
Department Name: Sch of Physics and Astronomy
Abstract
The Edinburgh Experimental Particle Physics group is currently working in three different running experiments and we are also working on several future projects.
The ATLAS experiment at the Large Hadron Collider (LHC): ATLAS is one of two detectors able to study a wide variety of particles created from the collision of protons at the highest energies ever created, and it addresses fundamental questions. The most well known is that of the origin of mass. The beautiful symmetry which underlies our understanding of particle interactions inherently demands that all particles are massless. This cannot be the case, and the elegant solution put forward is now known as the Higgs mechanism. The discovery of the Higgs boson has verified this, and now we must measure its properties in great detail. Another area addressed by ATLAS is the search for new heavy particles such as new heavy Higgs like particles or supersymmetric particles, which are predicted in models trying to address shortcomings of the Standard Model (SM), such as why there is dark matter.
The LHCb experiment at the LHC. Prior to the 1960s, it had been thought that matter and anti-matter would behave in the same way. However, it was discovered that this symmetry was violated, and that matter does not behave in an identical way to anti-matter. This is embodied in the phenomenon of CP violation and is essential to the understanding of the early universe. Shortly after the big bang there were equal amounts of matter and anti-matter. During expansion and cooling, matter and anti-matter would have annihilated into photons to leave a universe full of radiation, but no stars and galaxies. It was shown in 1967 by Sakarov that if three conditions, including CP violation, were met, then it would be possible for a small imbalance of matter over anti-matter to accrue, which would be sufficient to explain the existence of the universe. LHCb measures differences (CP violation) in behaviour of particles and antiparticle with at least one b or anti-b quark and searches for very rare decays of these particles, which could be affected by heavy unobserved particles.
The LUX-ZEPLIN experiment, which is the world's most sensitive apparatus searching for dark matter. It is well known that some 27% of the Universe is comprised of Dark Matter - that is matter of some form which does not interact in a way that produces radiation, or other easy to observe signatures. There are many theoretical candidates and resolution of this mystery must include the direct detection of our own galactic dark matter. We lead the collaboration's efforts to detect particularly well-motivated possibilities including axions and dark phonons.
We are also working hard on the design, development and construction of the upgraded detectors at the LHC for around 2020. The intensity of the beams will be increased and the data rates recorded by the detectors will increase by orders of magnitude. This requires building new detectors for precisely measuring trajectories of longlived particles, for measuring Cherenkov photons to determine their speed, and faster and more powerful simulation, and new ways to handle the massive data rates.
We have now completed the construction of the LUX-ZEPLIN project, expected to dominate direct searches for dark matter in the next decade. We work on simulations, control systems for the 10 tonnes of liquid xenon, and analysis.
We have grown our neutrino physics activities in the DUNE and Hyper-K experiments to be constructed. One of the most interesting facts of nature is that there are only three species of neutrinos, which until recently were thought to be massless. It is important to measure precisely the "mixing" between the species and to search for CP violation in neutrinos. We have also joined the MicroBooNE and SBND experiments, which will search for new, sterile, neutrinos which interact only via gravity but not with any of the fundamental interactions of the SM.
The ATLAS experiment at the Large Hadron Collider (LHC): ATLAS is one of two detectors able to study a wide variety of particles created from the collision of protons at the highest energies ever created, and it addresses fundamental questions. The most well known is that of the origin of mass. The beautiful symmetry which underlies our understanding of particle interactions inherently demands that all particles are massless. This cannot be the case, and the elegant solution put forward is now known as the Higgs mechanism. The discovery of the Higgs boson has verified this, and now we must measure its properties in great detail. Another area addressed by ATLAS is the search for new heavy particles such as new heavy Higgs like particles or supersymmetric particles, which are predicted in models trying to address shortcomings of the Standard Model (SM), such as why there is dark matter.
The LHCb experiment at the LHC. Prior to the 1960s, it had been thought that matter and anti-matter would behave in the same way. However, it was discovered that this symmetry was violated, and that matter does not behave in an identical way to anti-matter. This is embodied in the phenomenon of CP violation and is essential to the understanding of the early universe. Shortly after the big bang there were equal amounts of matter and anti-matter. During expansion and cooling, matter and anti-matter would have annihilated into photons to leave a universe full of radiation, but no stars and galaxies. It was shown in 1967 by Sakarov that if three conditions, including CP violation, were met, then it would be possible for a small imbalance of matter over anti-matter to accrue, which would be sufficient to explain the existence of the universe. LHCb measures differences (CP violation) in behaviour of particles and antiparticle with at least one b or anti-b quark and searches for very rare decays of these particles, which could be affected by heavy unobserved particles.
The LUX-ZEPLIN experiment, which is the world's most sensitive apparatus searching for dark matter. It is well known that some 27% of the Universe is comprised of Dark Matter - that is matter of some form which does not interact in a way that produces radiation, or other easy to observe signatures. There are many theoretical candidates and resolution of this mystery must include the direct detection of our own galactic dark matter. We lead the collaboration's efforts to detect particularly well-motivated possibilities including axions and dark phonons.
We are also working hard on the design, development and construction of the upgraded detectors at the LHC for around 2020. The intensity of the beams will be increased and the data rates recorded by the detectors will increase by orders of magnitude. This requires building new detectors for precisely measuring trajectories of longlived particles, for measuring Cherenkov photons to determine their speed, and faster and more powerful simulation, and new ways to handle the massive data rates.
We have now completed the construction of the LUX-ZEPLIN project, expected to dominate direct searches for dark matter in the next decade. We work on simulations, control systems for the 10 tonnes of liquid xenon, and analysis.
We have grown our neutrino physics activities in the DUNE and Hyper-K experiments to be constructed. One of the most interesting facts of nature is that there are only three species of neutrinos, which until recently were thought to be massless. It is important to measure precisely the "mixing" between the species and to search for CP violation in neutrinos. We have also joined the MicroBooNE and SBND experiments, which will search for new, sterile, neutrinos which interact only via gravity but not with any of the fundamental interactions of the SM.
Organisations
Publications
LHCb Collaboration
(2022)
Measurement of the lifetimes of promptly produced O c 0 and ? c 0 baryons
in Science Bulletin
LHCb Collaboration
(2022)
Study of the doubly charmed tetraquark [Formula: see text].
in Nature communications
ATLAS Collaboration
(2022)
A detailed map of Higgs boson interactions by the ATLAS experiment ten years after the discovery.
in Nature
Aaij R
(2022)
Observation of Two New Excited ?_{b}^{0} States Decaying to ?_{b}^{0}K^{-}p^{+}.
in Physical review letters
Aaij R
(2022)
Tests of Lepton Universality Using B^{0}?K_{S}^{0}l^{+}l^{-} and B^{+}?K^{*+}l^{+}l^{-} Decays.
in Physical review letters
Aaij R
(2022)
Search for massive long-lived particles decaying semileptonically at $${\sqrt{s}}=13\,\hbox {TeV}$$
in The European Physical Journal C
Aaij R
(2022)
Centrality determination in heavy-ion collisions with the LHCb detector
in Journal of Instrumentation
Aaij R
(2024)
Measurement of CP Violation in B^{0}??(?l^{+}l^{-})K_{S}^{0}(?p^{+}p^{-}) Decays.
in Physical review letters
Aaij R
(2022)
First Measurement of the Z ? µ + µ - Angular Coefficients in the Forward Region of p p Collisions at s = 13 TeV
in Physical Review Letters
Aaij R
(2022)
Analysis of Neutral B -Meson Decays into Two Muons
in Physical Review Letters
Aaij R
(2022)
Study of Z Bosons Produced in Association with Charm in the Forward Region
in Physical Review Letters
Aaij R
(2022)
J / ? photoproduction in Pb-Pb peripheral collisions at s N N = 5 TeV
in Physical Review C
Aaij R
(2022)
Measurement of the Nuclear Modification Factor and Prompt Charged Particle Production in p -Pb and p p Collisions at s N N = 5 TeV
in Physical Review Letters
Aaij R
(2022)
Evidence for a New Structure in the J / ? p and J / ? p ¯ Systems in B s 0 ? J / ? p p ¯ Decays
in Physical Review Letters
Aaij R
(2022)
Angular Analysis of D 0 ? p + p - µ + µ - and D 0 ? K + K - µ + µ - Decays and Search for C P Violation
in Physical Review Letters
Aaij R
(2022)
Measurement of the charm mixing parameter y C P - y C P K p using two-body D 0 meson decays
in Physical Review D
Aaij R
(2022)
Observation of the Decay ? b 0 ? ? c + t - ? ¯ t
in Physical Review Letters
Aaij R
(2022)
Measurement of the B s 0 ? µ + µ - decay properties and search for the B 0 ? µ + µ - and B s 0 ? µ + µ - ? decays
in Physical Review D
Aaij R
(2022)
Measurement of the photon polarization in ? b 0 ? ? ? decays
in Physical Review D
Aaij R
(2022)
Observation of the B 0 ? D ¯ * 0 K + p - and B s 0 ? D ¯ * 0 K - p + decays
in Physical Review D
Aad G
(2023)
Search for flavour-changing neutral-current couplings between the top quark and the photon with the ATLAS detector at s = 13 TeV
in Physics Letters B
Aad G
(2023)
Search for resonant WZ production in the fully leptonic final state in proton-proton collisions at $$\mathbf {\sqrt{s} = 13}$$ TeV with the ATLAS detector
in The European Physical Journal C
Aad G
(2022)
Determination of the parton distribution functions of the proton using diverse ATLAS data from pp collisions at $$\sqrt{s} = 7$$, 8 and 13 TeV
in The European Physical Journal C
Aad G
(2023)
Measurement of the Higgs boson mass with H ? ?? decays in 140 fb-1 of s = 13 TeV pp collisions with the ATLAS detector
in Physics Letters B
Aad G
(2023)
Tools for estimating fake/non-prompt lepton backgrounds with the ATLAS detector at the LHC
in Journal of Instrumentation
Aad G
(2023)
Search for Majorana neutrinos in same-sign WW scattering events from pp collisions at $$\sqrt{s}=13$$ TeV
in The European Physical Journal C
Aad G
(2023)
Search for heavy long-lived multi-charged particles in the full LHC Run 2 pp collision data at s = 13 TeV using the ATLAS detector
in Physics Letters B
Aad G
(2023)
Search for exclusive Higgs and Z boson decays to ?? and Higgs boson decays to K?? with the ATLAS detector
in Physics Letters B
Aad G
(2022)
Two-particle Bose-Einstein correlations in $${ pp }$$ collisions at $$\mathbf {\sqrt{s} = 13}$$ TeV measured with the ATLAS detector at the LHC
in The European Physical Journal C
Aad G
(2022)
Emulating the impact of additional proton-proton interactions in the ATLAS simulation by presampling sets of inelastic Monte Carlo events
in Computing and Software for Big Science
Aad G
(2023)
Measurement of exclusive pion pair production in proton-proton collisions at $$\sqrt{s}={7}\,\text {TeV}$$ with the ATLAS detector
in The European Physical Journal C
Aad G
(2023)
Observation of four-top-quark production in the multilepton final state with the ATLAS detector
in The European Physical Journal C
Aad G
(2023)
Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings.
in Physical review letters
Aad G
(2024)
Observation of W Z ? Production in p p Collisions at s = 13 TeV with the ATLAS Detector
in Physical Review Letters
Aad G
(2023)
Measurement of the nuclear modification factor of b-jets in 5.02 TeV Pb+Pb collisions with the ATLAS detector
in The European Physical Journal C
Aad G
(2023)
Measurement of the polarisation of W bosons produced in top-quark decays using dilepton events at s = 13 TeV with the ATLAS experiment
in Physics Letters B
Aad G
(2023)
Studies of the muon momentum calibration and performance of the ATLAS detector with pp collisions at $$\sqrt{s}=13$$ TeV
in The European Physical Journal C
Aad G
(2023)
Measurement of the total cross section and $$\rho $$-parameter from elastic scattering in pp collisions at $$\sqrt{s}=13$$ TeV with the ATLAS detector
in The European Physical Journal C
Aad G
(2023)
Measurement of the CP properties of Higgs boson interactions with $$\tau $$-leptons with the ATLAS detector
in The European Physical Journal C
Aad G
(2023)
Search for doubly charged Higgs boson production in multi-lepton final states using 139 fb$$^{-1}$$ of proton-proton collisions at $$\sqrt{s}$$ = 13 TeV with the ATLAS detector
in The European Physical Journal C
Aad G
(2023)
Observation of gauge boson joint-polarisation states in W±Z production from pp collisions at s = 13 TeV with the ATLAS detector
in Physics Letters B
Aad G
(2023)
Search for pair production of third-generation leptoquarks decaying into a bottom quark and a $$\tau $$-lepton with the ATLAS detector
in The European Physical Journal C
Aad G
(2022)
Performance of the ATLAS Level-1 topological trigger in Run 2
in The European Physical Journal C
Aad G
(2023)
Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector.
in Physical review letters