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
Aad G
(2022)
Performance of the ATLAS Level-1 topological trigger in Run 2
in The European Physical Journal C
LHCb Collaboration
(2022)
Measurement of the lifetimes of promptly produced O c 0 and ? c 0 baryons
in Science Bulletin
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)
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)
J / ? photoproduction in Pb-Pb peripheral collisions at s N N = 5 TeV
in Physical Review C
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)
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)
Measurement of the photon polarization in ? b 0 ? ? ? decays
in Physical Review D
Aad G
(2022)
Measurements of azimuthal anisotropies of jet production in Pb + Pb collisions at s NN = 5.02 TeV with the ATLAS detector
in Physical Review C
Aaij R
(2022)
Observation of Two New Excited ?_{b}^{0} States Decaying to ?_{b}^{0}K^{-}p^{+}.
in Physical review letters
Aaij R
(2022)
Centrality determination in heavy-ion collisions with the LHCb detector
in Journal of Instrumentation
Aad G
(2022)
Search for type-III seesaw heavy leptons in leptonic final states in pp collisions at $$\sqrt{s} = 13~\text {TeV}$$ with the ATLAS detector
in The European Physical Journal C
Aaij R
(2022)
Observation of the Decay ? b 0 ? ? c + t - ? ¯ t
in Physical Review Letters
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
(2022)
Observation of WWW Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector.
in Physical review letters
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
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 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
Aad G
(2022)
Search for new phenomena in three- or four-lepton events in pp collisions at s = 13 TeV with the ATLAS detector
in Physics Letters B
Aad G
(2022)
AtlFast3: The Next Generation of Fast Simulation in ATLAS
in Computing and Software for Big Science
Aad G
(2022)
Search for long-lived charginos based on a disappearing-track signature using 136 fb$$^{-1}$$ of pp collisions at $$\sqrt{s}$$ = 13 TeV with the ATLAS detector
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
Aad G
(2022)
Measurements of jet observables sensitive to b -quark fragmentation in t t ¯ events at the LHC with the ATLAS detector
in Physical Review D
Aad G
(2022)
Search for flavour-changing neutral-current interactions of a top quark and a gluon in pp collisions at $$\sqrt{s}=13$$ TeV with the ATLAS detector
in The European Physical Journal C
Aad G
(2022)
Measurement of the c-jet mistagging efficiency in $$t\bar{t}$$ events using pp collision data at $$\sqrt{s}=13$$ $$\text {TeV}$$ collected with the ATLAS detector
in The European Physical Journal C
Aad G
(2022)
Measurement of the energy asymmetry in $$t{\bar{t}}j$$ production at $$13\,$$TeV with the ATLAS experiment and interpretation in the SMEFT framework
in The European Physical Journal C
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
Aaij R
(2022)
Search for massive long-lived particles decaying semileptonically at $${\sqrt{s}}=13\,\hbox {TeV}$$
in The European Physical Journal C
LHCb Collaboration
(2022)
Study of the doubly charmed tetraquark [Formula: see text].
in Nature communications
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
(2022)
The ATLAS inner detector trigger performance in pp collisions at 13 TeV during LHC Run 2
in The European Physical Journal C
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
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
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
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)
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
(2022)
Measurement of the energy response of the ATLAS calorimeter to charged pions from $$W^{\pm }\rightarrow \tau ^{\pm }(\rightarrow \pi ^{\pm }\nu _{\tau })\nu _{\tau }$$ events in Run 2 data
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)
Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings.
in Physical review letters