Particle Physics Consolidated Grant 2019
Lead Research Organisation:
University of Bristol
Department Name: Physics
Abstract
The Bristol particle physics group will search for evidence of physics beyond the Standard Model, and work to understand the properties of new phenomena. We will carry out this study using a range of approaches and experiments.
At the CERN CMS experiment at the LHC, we will search for signatures of the production of dark matter and supersymmetric particles, using events with 'missing energy'. In the absence of a discovery, we will combine statistical information from our observations with results from cosmology and direct dark matter searches, to rule out potential theories of new physics. We will also use the very large datasets produced at the LHC to study the production and properties of the top quark, a standard model particle with unique properties.
We will use a complementary approach to search for new physics at the CERN LHCb experiment, looking for subtle signatures of new physics that manifest themselves in the decays of mesons containing heavy quarks. We will use similar approaches to test current ideas about the nature of fundamental quantum symmetries.
We will continue to use the NA62 experiment at the CERN SPS to study the decays of kaons to look for signs of new physics, and the SOLID experiment at the BR2 reactor to study neutrino oscillations on an ultra-short baseline of 5-10m. We will also participate in the Mu3e experiment to search for lepton flavour violation.
The group will pursue R&D for future experiments, including upgrades for CMS and LHCb, and the SHiP experiment at the CERN SPS which will use a very high intensity beam to search for 'dark particles' that are signatures of physics beyond the Standard Model. We will continue to work on the detailed design and optimisation of detectors for a future linear collider (ILC or CLIC) and the proposed future circular collider.
We will also continue our programme on the development of new sensors and technologies, including collaboration with industry and other academic disciplines in order to generate impact from our work.
At the CERN CMS experiment at the LHC, we will search for signatures of the production of dark matter and supersymmetric particles, using events with 'missing energy'. In the absence of a discovery, we will combine statistical information from our observations with results from cosmology and direct dark matter searches, to rule out potential theories of new physics. We will also use the very large datasets produced at the LHC to study the production and properties of the top quark, a standard model particle with unique properties.
We will use a complementary approach to search for new physics at the CERN LHCb experiment, looking for subtle signatures of new physics that manifest themselves in the decays of mesons containing heavy quarks. We will use similar approaches to test current ideas about the nature of fundamental quantum symmetries.
We will continue to use the NA62 experiment at the CERN SPS to study the decays of kaons to look for signs of new physics, and the SOLID experiment at the BR2 reactor to study neutrino oscillations on an ultra-short baseline of 5-10m. We will also participate in the Mu3e experiment to search for lepton flavour violation.
The group will pursue R&D for future experiments, including upgrades for CMS and LHCb, and the SHiP experiment at the CERN SPS which will use a very high intensity beam to search for 'dark particles' that are signatures of physics beyond the Standard Model. We will continue to work on the detailed design and optimisation of detectors for a future linear collider (ILC or CLIC) and the proposed future circular collider.
We will also continue our programme on the development of new sensors and technologies, including collaboration with industry and other academic disciplines in order to generate impact from our work.
Planned Impact
Impact generation is an explicit goal of the group activity. Our target partnerships are:
- Outreach to the general public, which has societal impact and indirect economic benefit through engagement with STEM subjects. The public have a strong interest in particle physics, which we will sustain through proactive engagement with talks, lab visits, and other targeted activities.
- Outreach to school students and teachers, aiming to stimulate young people's interest in STEM subjects. The Bristol-led HISPARC-UK offers sustained two-way engagement with students and teachers, enabling them to participate in a genuine research with clusters of schools building and operating research-quality cosmic ray detectors. Our annual Masterclass offers the opportunity to engage with sixth-form students (around 200 per year) and teachers in an organised annual event. We also host a number of sixth-form work experience students each year.
- Collaboration with UK Industry, transferring our knowledge to address commercial, industrial, medical and security applications. We will engage UK industry as commercial partners in the development and construction of systems and detectors, including using the LHC upgrade and ILC projects as a means of achieving knowledge transfer to UK industry, and offering openings to further contracts at CERN and other labs.
- The provision of trained physicists to industry. Our highly collaborative and technology-focussed research environment, backed up with training in transferable skills, equips both graduates and staff with an strong set of relevant credentials.
- The transfer of technology and techniques into other areas of scientific, medical and social research, including medical instrumentation and therapies, nuclear monitoring and safeguarding, and environmental and geological sciences.
- Pursuing Global Challenges, applying STFC-funded research to solving problems and stimulating economic development in the developing world.
- Outreach to the general public, which has societal impact and indirect economic benefit through engagement with STEM subjects. The public have a strong interest in particle physics, which we will sustain through proactive engagement with talks, lab visits, and other targeted activities.
- Outreach to school students and teachers, aiming to stimulate young people's interest in STEM subjects. The Bristol-led HISPARC-UK offers sustained two-way engagement with students and teachers, enabling them to participate in a genuine research with clusters of schools building and operating research-quality cosmic ray detectors. Our annual Masterclass offers the opportunity to engage with sixth-form students (around 200 per year) and teachers in an organised annual event. We also host a number of sixth-form work experience students each year.
- Collaboration with UK Industry, transferring our knowledge to address commercial, industrial, medical and security applications. We will engage UK industry as commercial partners in the development and construction of systems and detectors, including using the LHC upgrade and ILC projects as a means of achieving knowledge transfer to UK industry, and offering openings to further contracts at CERN and other labs.
- The provision of trained physicists to industry. Our highly collaborative and technology-focussed research environment, backed up with training in transferable skills, equips both graduates and staff with an strong set of relevant credentials.
- The transfer of technology and techniques into other areas of scientific, medical and social research, including medical instrumentation and therapies, nuclear monitoring and safeguarding, and environmental and geological sciences.
- Pursuing Global Challenges, applying STFC-funded research to solving problems and stimulating economic development in the developing world.
Publications
Aaij R
(2023)
Measurement of the mass difference and relative production rate of the O b - and ? b - baryons
in Physical Review D
Aaij R
(2021)
Observation of excited O c 0 baryons in O b - ? ? c + K - p - decays
in Physical Review D
Aaij R
(2023)
Study of charmonium decays to K S 0 K p in the B ? ( K S 0 K p ) K channels
in Physical Review D
Aaij R
(2020)
Measurement of f_{s}/f_{u} Variation with Proton-Proton Collision Energy and B-Meson Kinematics.
in Physical review letters
Aaij R
(2021)
Observation of a New Excited D_{s}^{+} Meson in B^{0}?D^{-}D^{+}K^{+}p^{-} Decays.
in Physical review letters
Aaij R
(2023)
Search for Rare Decays of D^{0} Mesons into Two Muons.
in Physical review letters
Aaij R
(2023)
Precision Measurement of CP Violation in the Penguin-Mediated Decay B_{s}^{0}???.
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
(2020)
Measurement of $${\psi {(2S)}} $$ production cross-sections in proton-proton collisions at $$\sqrt{s} =7$$ and $$13\text { TeV} $$
in The European Physical Journal C
Aaij R
(2021)
Observation of the ? b 0 ? ? c + K + K - p - decay
in Physics Letters B
Aaij R
(2019)
Search for Lepton-Universality Violation in B^{+}?K^{+}l^{+}l^{-} 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
(2019)
Measurement of the Mass Difference Between Neutral Charm-Meson Eigenstates.
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
(2021)
Observation of CP violation in two-body $$ {B}_{(s)}^0 $$-meson decays to charged pions and kaons
in Journal of High Energy Physics
Aaij R
(2020)
Strong constraints on the b ? s? photon polarisation from B0 ? K*0e+e- decays
in Journal of High Energy Physics
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
Aaij R
(2023)
Search for direct C P violation in charged charmless B ? P V 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
(2023)
Model-independent measurement of charm mixing parameters in B ¯ ? D 0 ( ? K S 0 p + p - ) µ - ? ¯ µ X decays
in Physical Review D
Aaij R
(2022)
Measurement of the photon polarization in ? b 0 ? ? ? decays
in Physical Review D
Aaij R
(2020)
Measurement of branching fraction ratios for B+ ? D*+D-K+, B+ ? D*-D+K+, and B0 ? D*-D0K+ decays
in Journal of High Energy Physics
Aaij R
(2019)
Observation of an Excited B_{c}^{+} State.
in Physical review letters
Aaij R
(2020)
First observation of the decay ? b 0 ? ? c ( 1 S ) p K -
in Physical Review D
Aaij R
(2023)
Search for C P violation using T ^ -odd correlations in B 0 ? p p ¯ K + p - decays
in Physical Review D
Aaij R
(2021)
Search for heavy neutral leptons in $$W^+\rightarrow \mu ^{+}\mu ^{\pm }\, \text {jet}$$ decays
in The European Physical Journal C
Aaij R
(2020)
Observation of Several Sources of CP Violation in B^{+}?p^{+}p^{+}p^{-} Decays.
in Physical review letters
Aaij R
(2020)
Measurement of the relative branching fractions of B + ? h + h ' + h ' - decays
in Physical Review D
Aaij R
(2021)
Observation of a new ? b 0 state
in Physical Review D
Aaij R
(2020)
Search for A^{'}?µ^{+}µ^{-} Decays.
in Physical review letters
Aaij R
(2021)
Precise measurement of the f s / f d ratio of fragmentation fractions and of B s 0 decay branching fractions
in Physical Review D
Aaij R
(2021)
Observation of Multiplicity Dependent Prompt ?_{c1}(3872) and ?(2S) Production in pp Collisions.
in Physical review letters
Aaij R
(2022)
First Measurement of the Z?µ^{+}µ^{-} Angular Coefficients in the Forward Region of pp Collisions at sqrt[s]=13 TeV.
in Physical review letters
Aaij R
(2019)
Measurements of CP asymmetries in charmless four-body $${\varLambda } ^0_{b} $$ and $${\varXi } ^0_{b} $$ decays
in The European Physical Journal C
Aaij R
(2020)
Isospin Amplitudes in ?_{b}^{0}?J/??(S^{0}) and ?_{b}^{0}?J/??^{0}(?) Decays.
in Physical review letters
Aaij R
(2021)
Search for C P violation in ? b - ? p K - K - decays
in Physical Review D
Aaij R
(2019)
Measurement of the B c - meson production fraction and asymmetry in 7 and 13 TeV p p collisions
in Physical Review D
Aaij R
(2020)
Observation of Enhanced Double Parton Scattering in Proton-Lead Collisions at sqrt[s_{NN}]=8.16 TeV.
in Physical review letters
Aaij R
(2020)
Measurement of the $${\eta _{c}} (1S)$$ production cross-section in $$p $$ $$p $$ collisions at $$\sqrt{s} = 13$$ $$\, \text {TeV}$$
in The European Physical Journal C
Aaij R
(2019)
Measurement of Charged Hadron Production in Z-Tagged Jets in Proton-Proton Collisions at sqrt[s]=8 TeV.
in Physical review letters
Aaij R
(2020)
Amplitude analysis of the B + ? D + D - K + decay
in Physical Review D
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
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
Aaij R
(2021)
Measurement of the branching fraction of the $${ {B} ^0} {\rightarrow }{ {D} ^+_{s}} { {\pi } ^-} $$ decay
in The European Physical Journal C
Aaij R
(2023)
Evidence of a J/?K_{S}^{0} Structure in B^{0}?J/??K_{S}^{0} Decays.
in Physical review letters
Aaij R
(2023)
Test of Lepton Universality in b?sl^{+}l^{-} Decays.
in Physical review letters
Aaij R
(2023)
Measurement of the Prompt D^{0} Nuclear Modification Factor in p-Pb Collisions at sqrt[s_{NN}]=8.16 TeV.
in Physical review letters
Aaij R
(2022)
Observation of Two New Excited ?_{b}^{0} States Decaying to ?_{b}^{0}K^{-}p^{+}.
in Physical review letters
Aaij R
(2023)
Measurement of the Time-Integrated CP Asymmetry in D^{0}?K^{-}K^{+} Decays.
in Physical review letters
Aaij R
(2020)
Precision measurement of the $$ {\varXi}_{cc}^{++} $$ mass
in Journal of High Energy Physics
Title | "Data" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" |
Description | Data points used in analysis in log_10(S2)-S1 space |
Type Of Material | Database/Collection of data |
Year Produced | 2023 |
Provided To Others? | Yes |
URL | https://www.hepdata.net/record/145093 |
Title | "Efficiency" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" |
Description | Data selection efficiency as a function of nuclear recoil energy |
Type Of Material | Database/Collection of data |
Year Produced | 2023 |
Provided To Others? | Yes |
URL | https://www.hepdata.net/record/145092 |
Title | "SDn cross section" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" |
Description | 90% CL WIMP SDn cross sections, including sensitivities and nuclear structure uncertainties |
Type Of Material | Database/Collection of data |
Year Produced | 2023 |
Provided To Others? | Yes |
URL | https://www.hepdata.net/record/145090 |
Title | "SDp cross section" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" |
Description | 90% CL WIMP SDp cross sections, including sensitivities and nuclear structure uncertainties |
Type Of Material | Database/Collection of data |
Year Produced | 2023 |
Provided To Others? | Yes |
URL | https://www.hepdata.net/record/145091 |
Title | "SI cross section" of "First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment" |
Description | 90% CL WIMP SI cross sections, including sensitivities |
Type Of Material | Database/Collection of data |
Year Produced | 2023 |
Provided To Others? | Yes |
URL | https://www.hepdata.net/record/145089 |
Description | Graphcore's IPUs |
Organisation | Graphcore |
Country | United Kingdom |
Sector | Private |
PI Contribution | Evaluating Graphcore's novel IPU processors, and, for the first time, implementing Particle Physics relevant software on them. Of particular interest not only to us, but also the community interested in these novel processors, is that we did not only use IPUs for machine learning (although we did that, too), but also non ML applications (Kalman Filter). Our work was also beneficial to our industrial partner in optimising and debugging their API. This work continued and led to IPUs being considered as an option for the real time analysis of LHCb events in LHCb Upgrade II. We have implement the highly complex reconstruction of the TORCH time of flight detector on IPUs and seen impressive speed gains compared to previous implementations using CPUs. |
Collaborator Contribution | Cloud Access to IPUs and technical support. |
Impact | Paper: https://inspirehep.net/literature/1812756 (accepted for publication) |
Start Year | 2019 |