ALICE Upgrade 2 (Silicon Physicist post)
Lead Research Organisation:
University of Liverpool
Department Name: Physics
Abstract
Quantum-ChromoDynamics (QCD) is the theory of the strong force and understanding its properties has been the focus of
intense World-wide research over the past half century. QCD forms a major part of the Standard Model and its
understanding is crucial in producing an overall theory to describe the properties of matter and the fundamental forces of
nature including a grand unification theory to explain how the Universe evolved from the Big Bang.
The principal purpose of our research is to use ultra-relativistic heavy-ion interactions to study QCD at extreme energy
densities. Theoretical models predict that under very extreme conditions of high energy densities the quarks, which are
confined in normal nuclear matter, will be freed and nuclear matter will undergo a phase transition into a hot, dense plasma
of free quarks and gluons known as a Quark-Gluon Plasma (QGP). It is thought that such a state of matter would have
existed until about 10^-5 seconds after the Big Bang, after which time the Universe would have cooled sufficiently for
protons and neutrons to form.
The physics aim of this research is to study the strong force under these extreme conditions and, in particular, explore the
properties of this exotic state of matter. By studying the QGP, we hope to address the fundamental questions of quark
confinement and how quarks gain a large effective mass in hadrons due to the strong force (accounting for 99% of atomic
mass).
In order to create the conditions required to produce a QGP we must collide heavy nuclei together at the highest possible
energies, creating tiny hot (~10^13K) and dense fireballs. As the resulting QGP will only last for about 10-22 seconds,
before condensing in to thousands of elementary particles, we must also use the most sophisticated detectors to analyse
these collisions.
The LHC collides lead ions at centre-of-mass energies of 2.76 TeV in ALICE. We also collide protons together as this forms
an excellent reference data set. Moreover, the excellent particle identification and tracking make ALICE an ideal detector
to study the global aspects of proton-proton collisions in their own right.
This field of research employs about two thousand physicists around the world and ALICE is the most sophisticated
experiment ever built in the field, studying heavy-ion collisions at centre-of-mass energies over an order of magnitude
greater than its nearest rival. It hence represents the pinnacle of research in this field.
The ALICE collaboration is now preparing for the second LHC Upgrade scheduled to start in 2018. These upgrades are
required to cope with the anticipated increase in lead beam luminosity which will increase beam intensities by an order of
magnitude. The main motivation for the luminosity upgrade is to achieve a precise, quantitative understand of the
properties of the QGP by focusing on rare probes both at low and high transverse momenta as well as on multidimensional
analysis of such probes with respect to centrality, event plane, multi-particle correlations, etc.
intense World-wide research over the past half century. QCD forms a major part of the Standard Model and its
understanding is crucial in producing an overall theory to describe the properties of matter and the fundamental forces of
nature including a grand unification theory to explain how the Universe evolved from the Big Bang.
The principal purpose of our research is to use ultra-relativistic heavy-ion interactions to study QCD at extreme energy
densities. Theoretical models predict that under very extreme conditions of high energy densities the quarks, which are
confined in normal nuclear matter, will be freed and nuclear matter will undergo a phase transition into a hot, dense plasma
of free quarks and gluons known as a Quark-Gluon Plasma (QGP). It is thought that such a state of matter would have
existed until about 10^-5 seconds after the Big Bang, after which time the Universe would have cooled sufficiently for
protons and neutrons to form.
The physics aim of this research is to study the strong force under these extreme conditions and, in particular, explore the
properties of this exotic state of matter. By studying the QGP, we hope to address the fundamental questions of quark
confinement and how quarks gain a large effective mass in hadrons due to the strong force (accounting for 99% of atomic
mass).
In order to create the conditions required to produce a QGP we must collide heavy nuclei together at the highest possible
energies, creating tiny hot (~10^13K) and dense fireballs. As the resulting QGP will only last for about 10-22 seconds,
before condensing in to thousands of elementary particles, we must also use the most sophisticated detectors to analyse
these collisions.
The LHC collides lead ions at centre-of-mass energies of 2.76 TeV in ALICE. We also collide protons together as this forms
an excellent reference data set. Moreover, the excellent particle identification and tracking make ALICE an ideal detector
to study the global aspects of proton-proton collisions in their own right.
This field of research employs about two thousand physicists around the world and ALICE is the most sophisticated
experiment ever built in the field, studying heavy-ion collisions at centre-of-mass energies over an order of magnitude
greater than its nearest rival. It hence represents the pinnacle of research in this field.
The ALICE collaboration is now preparing for the second LHC Upgrade scheduled to start in 2018. These upgrades are
required to cope with the anticipated increase in lead beam luminosity which will increase beam intensities by an order of
magnitude. The main motivation for the luminosity upgrade is to achieve a precise, quantitative understand of the
properties of the QGP by focusing on rare probes both at low and high transverse momenta as well as on multidimensional
analysis of such probes with respect to centrality, event plane, multi-particle correlations, etc.
Planned Impact
The main beneficiaries of this upgrade will be experimentalists and theorists working in the field of hot Quantum
Chromodynamics. They will directly benefit from the new insights that will arise out of the research, made possible by this
Upgrade. The results of the subsequent research will be disseminated in high impact journals, through conference talks
and seminars so as to reach as wide an audience as possible. More broadly, both the technologies developed during the
Upgrade and the resulting research will also be of relevance to researchers in other fields, including other areas of nuclear
physics, particle physics, astrophysics and cosmology. Some of the hardware developments related to the Birmingham
design of the original ALICE trigger subsystem have already had impact, having been adopted by another experiment at
CERN. Future developments that are foreseen in this proposal will potentially have relevance to a new generation of
experiments planning to run in continuous data taking mode. The ITS Upgrade project will develop MAPS technologies, an
area where the UK is already considered to be a world leader. Such technologies will not only have applications for other
particle detectors but are likely to have applications in the areas of medicine and security.
Another strand revolves around the public understanding of science. The research that is related to this proposal has the
potential to capture the imagination and to inspire a new generation of scientists. The research programme which will arise
from this Upgrade is involved in studying matter as it would have existed a fraction of a second after the Big Bang. This
aspect is relevant to the evolution of the Early Universe and the possible existence of (strange) quark matter stars.
Members of the ALICE-UK collaboration have given over 70 public lectures over the past five years and been involved in
many other public outreach events to school children, teachers, and members of the general public.
Chromodynamics. They will directly benefit from the new insights that will arise out of the research, made possible by this
Upgrade. The results of the subsequent research will be disseminated in high impact journals, through conference talks
and seminars so as to reach as wide an audience as possible. More broadly, both the technologies developed during the
Upgrade and the resulting research will also be of relevance to researchers in other fields, including other areas of nuclear
physics, particle physics, astrophysics and cosmology. Some of the hardware developments related to the Birmingham
design of the original ALICE trigger subsystem have already had impact, having been adopted by another experiment at
CERN. Future developments that are foreseen in this proposal will potentially have relevance to a new generation of
experiments planning to run in continuous data taking mode. The ITS Upgrade project will develop MAPS technologies, an
area where the UK is already considered to be a world leader. Such technologies will not only have applications for other
particle detectors but are likely to have applications in the areas of medicine and security.
Another strand revolves around the public understanding of science. The research that is related to this proposal has the
potential to capture the imagination and to inspire a new generation of scientists. The research programme which will arise
from this Upgrade is involved in studying matter as it would have existed a fraction of a second after the Big Bang. This
aspect is relevant to the evolution of the Early Universe and the possible existence of (strange) quark matter stars.
Members of the ALICE-UK collaboration have given over 70 public lectures over the past five years and been involved in
many other public outreach events to school children, teachers, and members of the general public.
Publications
Acharya S
(2023)
Measurements of azimuthal anisotropies at forward and backward rapidity with muons in high-multiplicity p-Pb collisions at s NN = 8.16 TeV
in Physics Letters B
Acharya S
(2023)
Azimuthal correlations of heavy-flavor hadron decay electrons with charged particles in pp and p-Pb collisions at $$\pmb {\sqrt{s_{\mathrm{ {NN}}}}}$$ = 5.02 TeV
in The European Physical Journal C
Acharya S
(2024)
Measurement of the impact-parameter dependent azimuthal anisotropy in coherent ?0 photoproduction in Pb-Pb collisions at s NN = 5.02 TeV
in Physics Letters B
Acharya S
(2023)
Accessing the strong interaction between ? baryons and charged kaons with the femtoscopy technique at the LHC
in Physics Letters B
Acharya S
(2020)
Global baryon number conservation encoded in net-proton fluctuations measured in Pb-Pb collisions at s NN = 2.76 TeV
in Physics Letters B
Acharya S
(2017)
Charged-particle multiplicity distributions over a wide pseudorapidity range in proton-proton collisions at $$\sqrt{s}=$$ s = 0.9, 7, and 8 TeV
in The European Physical Journal C
Acharya S
(2019)
Analysis of the apparent nuclear modification in peripheral Pb-Pb collisions at 5.02 TeV
in Physics Letters B
Acharya S
(2018)
Longitudinal asymmetry and its effect on pseudorapidity distributions in Pb-Pb collisions at s NN = 2.76 TeV
in Physics Letters B
Acharya S
(2021)
Inclusive $$\text {J}/\psi $$ production at midrapidity in pp collisions at $$\sqrt{s} = 13$$ TeV
in The European Physical Journal C
Acharya S
(2023)
Measurement of the Lifetime and ? Separation Energy of _{?}^{3}H.
in Physical review letters
Acharya S
(2023)
Light (anti)nuclei production in Pb-Pb collisions at s N N = 5.02 TeV
in Physical Review C
Acharya S
(2017)
Measurement of D-meson production at mid-rapidity in pp collisions at $${\sqrt{s}=7}$$ s = 7 TeV
in The European Physical Journal C
Acharya S
(2019)
Suppression of ? ( 1520 ) resonance production in central Pb-Pb collisions at s NN = 2.76 TeV
in Physical Review C
Acharya S
(2020)
? production in p-Pb collisions at s NN = 8.16 TeV
in Physics Letters B
Acharya S
(2024)
System-size dependence of the hadronic rescattering effect at energies available at the CERN Large Hadron Collider
in Physical Review C
Acharya S
(2018)
Measurement of Z0-boson production at large rapidities in Pb-Pb collisions at s NN = 5.02 TeV
in Physics Letters B
Acharya S
(2023)
Enhanced Deuteron Coalescence Probability in Jets.
in Physical review letters
Acharya S
(2018)
Measurement of the inclusive J/ $$\psi $$ ? polarization at forward rapidity in pp collisions at $$\mathbf {\sqrt{s} = 8}$$ s = 8 TeV
in The European Physical Journal C
Acharya S
(2023)
$$\Sigma (1385)^{\pm }$$ resonance production in Pb-Pb collisions at $$\sqrt{s_{\textrm{NN}}}~=~5.02$$ TeV
in The European Physical Journal C
Acharya S
(2021)
Inclusive heavy-flavour production at central and forward rapidity in Xe-Xe collisions at s NN = 5.44 TeV
in Physics Letters B
Acharya S
(2021)
Centrality dependence of J/? and ?(2S) production and nuclear modification in p-Pb collisions at $$ \sqrt{s_{\mathrm{NN}}} $$ = 8.16 TeV
in Journal of High Energy Physics
Acharya S
(2021)
ALICE Collaboration
in Nuclear Physics A
Acharya S
(2024)
Measurement of (anti)alpha production in central Pb-Pb collisions at s NN = 5.02 TeV
in Physics Letters B
Acharya S
(2024)
Measurement of the low-energy antitriton inelastic cross section
in Physics Letters B
Acharya S
(2021)
Transverse-momentum and event-shape dependence of D-meson flow harmonics in Pb-Pb collisions at s NN = 5.02 TeV
in Physics Letters B
Acharya S
(2018)
First measurement of ? c 0 production in pp collisions at s = 7 TeV
in Physics Letters B
Acharya S
(2021)
?_{c}^{+} Production and Baryon-to-Meson Ratios in pp and p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV at the LHC.
in Physical review letters
Acharya S
(2023)
Study of flavor dependence of the baryon-to-meson ratio in proton-proton collisions at s = 13 TeV
in Physical Review D
Acharya S
(2021)
Kaon-proton strong interaction at low relative momentum via femtoscopy in Pb-Pb collisions at the LHC
in Physics Letters B
Acharya S
(2021)
First measurement of the |t|-dependence of coherent J/? photonuclear production
in Physics Letters B
Acharya S
(2020)
Centrality and transverse momentum dependence of inclusive J/? production at midrapidity in Pb-Pb collisions at s NN = 5.02 TeV
in Physics Letters B
Acharya S
(2021)
Jet-associated deuteron production in pp collisions at s = 13 TeV
in Physics Letters B
Acharya S
(2025)
Particle production as a function of charged-particle flattenicity in p p collisions at s = 13 TeV
in Physical Review D
Acharya S
(2022)
Characterizing the initial conditions of heavy-ion collisions at the LHC with mean transverse momentum and anisotropic flow correlations
in Physics Letters B
Acharya S
(2019)
Centrality and pseudorapidity dependence of the charged-particle multiplicity density in Xe-Xe collisions at s NN = 5.44 TeV
in Physics Letters B
Acharya S
(2024)
Femtoscopic correlations of identical charged pions and kaons in p p collisions at s = 13 TeV with event-shape selection
in Physical Review C
Acharya S
(2018)
Azimuthally-differential pion femtoscopy relative to the third harmonic event plane in Pb-Pb collisions at s NN = 2.76 TeV
in Physics Letters B
Acharya S
(2022)
Production of K * ( 892 ) 0 and ? ( 1020 ) in p p and Pb - Pb collisions at s N N = 5.02 TeV
in Physical Review C
Acharya S
(2020)
K * ( 892 ) 0 and ? ( 1020 ) production at midrapidity in p p collisions at s = 8 TeV
in Physical Review C
Acharya S
(2020)
Dielectron production in proton-proton and proton-lead collisions at s NN = 5.02 TeV
in Physical Review C
Acharya S
(2023)
Measurement of the ? hyperon lifetime
in Physical Review D
Acharya S
(2023)
Neutron emission in ultraperipheral Pb-Pb collisions at s N N = 5.02 TeV
in Physical Review C
Acharya S
(2020)
Multiplicity dependence of inclusive J/? production at midrapidity in pp collisions at s = 13 TeV
in Physics Letters B
Acharya S
(2018)
Production of 4He and 4 He ? in Pb-Pb collisions at s NN = 2.76 TeV at the LHC
in Nuclear Physics A
Acharya S
(2022)
Investigating the role of strangeness in baryon-antibaryon annihilation at the LHC
in Physics Letters B
Acharya S
(2018)
Neutral pion and $$\eta $$ ? meson production in p-Pb collisions at $$\sqrt{s_{\mathrm{NN}}}$$ s NN = 5.02 TeV
in The European Physical Journal C
Acharya S
(2019)
Charged-particle pseudorapidity density at mid-rapidity in p-Pb collisions at $$\pmb {\sqrt{s_{\scriptscriptstyle {\mathrm{NN}}}}}$$ s NN = 8.16 TeV
in The European Physical Journal C
Acharya S
(2024)
Emergence of Long-Range Angular Correlations in Low-Multiplicity Proton-Proton Collisions.
in Physical review letters
Acharya S
(2022)
General balance functions of identified charged hadron pairs of (p,K,p) in Pb-Pb collisions at s NN = 2.76 TeV
in Physics Letters B
Acharya S
(2022)
Polarization of ? and ?[over ¯] Hyperons along the Beam Direction in Pb-Pb Collisions at sqrt[s]_{NN}=5.02 TeV.
in Physical review letters
| Description | The ALICE experiment at the CERN LHC has created the highest temperatures and densities every produced in an experiment and re-created the primordial soup which would have existed up to 10 millionths of a second after the Big Bang. There are far too many key findings to list here but we have discovered this super hot and dense primordial soup behaves like a perfect liquid - the most perfect liquid every produced. |
| Exploitation Route | This is an ongoing experiment, which will continue to upgrade and take data until at least 2030. |
| Sectors | Education Other |
| Description | ALICE Collaboration |
| Organisation | European Organization for Nuclear Research (CERN) |
| Department | ALICE Collaboration |
| Country | Switzerland |
| Sector | Public |
| PI Contribution | Data analysis of LHC data from Run1 and Run2 (heavy-flavour physics working group). ITS upgrade project: Monte Carlo simulations, construction of modules and staves for the Outer Barrel. Supervision of UG and PhD student projects. Meetings of ALICE-UK research groups (Univ. of Birmingham, Univ. of Liverpool, STFC Daresbury). Presentations at conferences, meetings and workshops. |
| Collaborator Contribution | Access to beam time, data, GRID and other CERN infrastructure and resources, ALICE collaboration international network etc. |
| Impact | Publications. Training of UG and PhD students and research staff. Invitations to speak at meetings, workshops, conferences. |
| Start Year | 2012 |
| Description | International Women Day |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Other audiences |
| Results and Impact | Panel Q&A ans discussion around the screening of the film 'Picture a scientist' by Sharon Shattuck & Ian Cheney (https://www.pictureascientist.com/) |
| Year(s) Of Engagement Activity | 2022 |