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
Aaij R
(2023)
$${ {J}/\psi }$$ and $${ {D}} ^0$$ production in $$\sqrt{s_{\scriptscriptstyle \text {NN}}} =68.5\,\text {GeV} $$ PbNe collisions
in The European Physical Journal C
ATLAS Collaboration
(2022)
A detailed map of Higgs boson interactions by the ATLAS experiment ten years after the discovery.
in Nature
Aaij R
(2023)
A study of $$C\!P$$ violation in the decays $${ {B} ^\pm } \rightarrow [{ {K} ^+} { {K} ^-} { {\uppi } ^+} { {\uppi } ^-} ]_{D} h^{\pm }$$ ($$h = K, \pi $$) and $${ {B} ^\pm } \rightarrow [{ {\uppi } ^+} { {\uppi } ^-} { {\uppi } ^+} { {\uppi } ^-} ]_{D} h^{\pm }$$
in The European Physical Journal C
Aad G
(2024)
Accuracy versus precision in boosted top tagging with the ATLAS detector
in Journal of Instrumentation
Aaij R
(2023)
Amplitude analysis of B 0 ? D ¯ 0 D s + p - and B + ? D - D s + p + decays
in Physical Review D
Aaij R
(2023)
Amplitude analysis of the ? c + ? p K - p + decay and ? c + baryon polarization measurement in semileptonic beauty hadron decays
in Physical Review D
Aaij R
(2022)
Analysis of Neutral B-Meson Decays into Two Muons.
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 CP Violation.
in Physical review letters
Aad G
(2023)
ATLAS flavour-tagging algorithms for the LHC Run 2 pp collision dataset
in The European Physical Journal C
Aad G
(2022)
AtlFast3: The Next Generation of Fast Simulation in ATLAS
in Computing and Software for Big Science
Aad G
(2024)
Azimuthal Angle Correlations of Muons Produced via Heavy-Flavor Decays in 5.02 TeV Pb+Pb and pp Collisions with the ATLAS Detector.
in Physical review letters
Aad G
(2024)
Beam-induced backgrounds measured in the ATLAS detector during local gas injection into the LHC beam vacuum
in Journal of Instrumentation
Aad G
(2024)
Calibration of a soft secondary vertex tagger using proton-proton collisions at s = 13 TeV with the ATLAS detector
in Physical Review D
Aaij R
(2022)
Centrality determination in heavy-ion collisions with the LHCb detector
in Journal of Instrumentation
Aaij R
(2023)
Charmonium production in pNe collisions at $$\sqrt{s_{\scriptscriptstyle \text {NN}}} =68.5$$ GeV
in The European Physical Journal C
ATLAS Collaboration
(2024)
Combination and summary of ATLAS dark matter searches interpreted in a 2HDM with a pseudo-scalar mediator using 139 fb-1 of s=13 TeV pp collision data.
in Science bulletin
Hayrapetyan A
(2024)
Combination of Measurements of the Top Quark Mass from Data Collected by the ATLAS and CMS Experiments at sqrt[s]=7 and 8 TeV.
in Physical review letters
Aad G
(2024)
Combination of Searches for Higgs Boson Pair Production in p p Collisions at s = 13 TeV with the ATLAS Detector
in Physical Review Letters
Aad G
(2024)
Combination of searches for pair-produced leptoquarks at s = 13 TeV with the ATLAS detector
in Physics Letters B
Aad G
(2024)
Combination of Searches for Resonant Higgs Boson Pair Production Using pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector.
in Physical review letters
Aad G
(2025)
Combination of searches for singly produced vectorlike top quarks in p p collisions at s = 13 TeV with the ATLAS detector
in Physical Review D
Aad G
(2023)
Comparison of inclusive and photon-tagged jet suppression in 5.02 TeV Pb+Pb collisions with ATLAS
in Physics Letters B
Aad G
(2022)
Constraints on Higgs boson production with large transverse momentum using H ? b b ¯ decays in the ATLAS detector
in Physical Review D
Aad G
(2022)
Constraints on Higgs boson properties using $$WW^{*}(\rightarrow e\nu \mu \nu )jj$$ production in $$36.1\,\mathrm{fb}^{-1}$$ of $$\sqrt{s}=13$$ TeV pp collisions with the ATLAS detector
in The European Physical Journal C
Aad G
(2023)
Constraints on spin-0 dark matter mediators and invisible Higgs decays using ATLAS 13 TeV pp collision data with two top quarks and missing transverse momentum in the final state
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
(2024)
Determination of the Relative Sign of the Higgs Boson Couplings to W and Z Bosons Using WH Production via Vector-Boson Fusion with the ATLAS Detector.
in Physical review letters
Aaij R
(2023)
Direct C P violation in charmless three-body decays of B ± mesons
in Physical Review D
Aad G
(2022)
Direct constraint on the Higgs-charm coupling from a search for Higgs boson decays into charm quarks with the ATLAS detector
in The European Physical Journal C
Aad G
(2024)
Disentangling Sources of Momentum Fluctuations in Xe + Xe and Pb + Pb Collisions with the ATLAS Detector
in Physical Review Letters
Aad G
(2024)
Electron and photon energy calibration with the ATLAS detector using LHC Run 2 data
in Journal of Instrumentation
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
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
Aad G
(2024)
Evidence for the Higgs Boson Decay to a Z Boson and a Photon at the LHC.
in Physical review letters
Aaij R
(2023)
Evidence of a J/?K_{S}^{0} Structure in B^{0}?J/??K_{S}^{0} Decays.
in Physical review letters
Aad G
(2023)
Evidence of off-shell Higgs boson production from ZZ leptonic decay channels and constraints on its total width with the ATLAS detector
in Physics Letters B
Aad G
(2023)
Fast b-tagging at the high-level trigger of the ATLAS experiment in LHC Run 3
in Journal of Instrumentation
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
(2023)
First observation of the B + ? D s + D s - K + decay
in Physical Review D
Aaij R
(2022)
J / ? photoproduction in Pb-Pb peripheral collisions at s N N = 5 TeV
in Physical Review C