Hunt for Exotic Particles: Dibaryons
Lead Research Organisation:
University of York
Department Name: Physics
Abstract
The vast majority of the "mass" of visible matter around us is in fact not really mass. It arises from the interaction energy of the components of the proton and neutron, the quarks and gluons. Because of Einstein's famous equivalence of mass and Energy (E=mc^2) the violent interactions of these subatomic particles can generate mass. For the matter around us on Earth and the matter visible in the stars of the night sky these mass generation mechanisms are much more relevant than the mass arising from the recently discovered Higgs, which accounts for less than 1% of the mass of the atomic nucleus. The mechanism of how quarks and gluons are confined into the bound systems of nucleons, which are the building blocks of the nuclei around us, is not well established. The basic theory of how they interact (Quantum Chromo Dynamics or QCD) has been proposed for some time, but how QCD manifests at the scale of the nucleon or other hadrons is not well understood. It is one of the biggest unsolved scientific problem in modern physics.
Based on the QCD theory describing how quarks interact (specifically color confinement) one expects that there should be many possible bound states of quarks and gluons. Until very recent years the zoo of bound systems comprised only baryons (qqq) and mesons (qqbar). However in addition the gg and ggg glueball states, tetra-quark systems and possibly pentaquark states are not ruled out by the basic principles of QCD. The field has been revolutionized by the recently discovered system Zc(c cbar d ubar). The race is on to establish the other exotic beasts of QCD which will give a totally new constraint and perspective on the nature of strongly interacting matter. I lead one of the most promising future directions to further our knowledge of the nature of matter, the hunt for dibaryons - mysterious six-quark states.
The possibility of exotic dibaryonic states was first proposed by F. Dyson in 1964, just half a year after the Gell-Mann's publication of the quark model. However, this topic received particular attention only after Jaffe's proposal of the so-called H-dibaryon, a uuddss state. I recently led research which has established the existence of a particle made from 6 quarks - the d* dibaryon: a uuuddd state. This is one of the biggest results in the field of strongly interacting matter in the past decade and provides a new window to investigate our understanding of QCD. This exotic object has a high angular momentum, with all six quarks in the ground state having their spins aligned. This d* resonance was investigated in reactions of proton beams on nuclei by the WASA collaboration, largely under my leadership, and is part of an ongoing program. I wish to lead a completely new research branch to investigate this object using beams of high energy photons and electrons to search for it's sister particles. These are the crucial missing piece of the jigsaw needed to unambiguously establish the new exotic particle. I will also establish how the new dibaryon particle interacts with the photon and the electron - it's electromagnetic properties. This will allow the size of the dibaryon to be constrained, enabling the genuine dibaryon with all 6 quarks tightly packed to be distinguished from a molecular-type object with two packages of 3 quarks each.
The new field of dibaryon physics will have major impact on a wide range of research areas including primordial nucleosynthesis, star dynamics, dark matter searches and the nature of quark confinement.
Based on the QCD theory describing how quarks interact (specifically color confinement) one expects that there should be many possible bound states of quarks and gluons. Until very recent years the zoo of bound systems comprised only baryons (qqq) and mesons (qqbar). However in addition the gg and ggg glueball states, tetra-quark systems and possibly pentaquark states are not ruled out by the basic principles of QCD. The field has been revolutionized by the recently discovered system Zc(c cbar d ubar). The race is on to establish the other exotic beasts of QCD which will give a totally new constraint and perspective on the nature of strongly interacting matter. I lead one of the most promising future directions to further our knowledge of the nature of matter, the hunt for dibaryons - mysterious six-quark states.
The possibility of exotic dibaryonic states was first proposed by F. Dyson in 1964, just half a year after the Gell-Mann's publication of the quark model. However, this topic received particular attention only after Jaffe's proposal of the so-called H-dibaryon, a uuddss state. I recently led research which has established the existence of a particle made from 6 quarks - the d* dibaryon: a uuuddd state. This is one of the biggest results in the field of strongly interacting matter in the past decade and provides a new window to investigate our understanding of QCD. This exotic object has a high angular momentum, with all six quarks in the ground state having their spins aligned. This d* resonance was investigated in reactions of proton beams on nuclei by the WASA collaboration, largely under my leadership, and is part of an ongoing program. I wish to lead a completely new research branch to investigate this object using beams of high energy photons and electrons to search for it's sister particles. These are the crucial missing piece of the jigsaw needed to unambiguously establish the new exotic particle. I will also establish how the new dibaryon particle interacts with the photon and the electron - it's electromagnetic properties. This will allow the size of the dibaryon to be constrained, enabling the genuine dibaryon with all 6 quarks tightly packed to be distinguished from a molecular-type object with two packages of 3 quarks each.
The new field of dibaryon physics will have major impact on a wide range of research areas including primordial nucleosynthesis, star dynamics, dark matter searches and the nature of quark confinement.
Organisations
- University of York (Fellow, Lead Research Organisation)
- Brookhaven National Laboratory (Collaboration)
- UNIVERSITY OF GLASGOW (Collaboration)
- University of Basel (Collaboration)
- National Institute for Nuclear Physics (Collaboration)
- JLab (Collaboration)
- Ruhr University Bochum (Collaboration)
- University of Bonn (Collaboration)
- Johannes Gutenberg University of Mainz (Collaboration)
- Khon Kaen University (Collaboration)
Publications
Acker A
(2020)
The CLAS12 Forward Tagger
in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Adlarson P
(2018)
Isotensor Dibaryon in the pp?ppp^{+}p^{-} Reaction?
in Physical review letters
Adlarson P
(2020)
Differential cross sections for neutron-proton scattering in the region of the d * ( 2380 ) dibaryon resonance
in Physical Review C
Adlarson P
(2018)
Importance of d-wave contributions in the charge symmetry breaking reaction d d ? 4 He p 0
in Physics Letters B
Adlarson P
(2020)
Search for ? mesic 3He with the WASA-at-COSY facility in the p d ? 3 He 2 ? and p d ? 3 He 6 ? reactions
in Physics Letters B
Adlarson P
(2020)
Corrigendum to "Isoscalar single-pion production in the region of Roper and d?(2380) resonances" [Phys. Lett. B 774 (2017) 599]
in Physics Letters B
Adlarson P
(2020)
Search for the ? mesic He 3 in the p d ? d p p 0 reaction with the WASA-at-COSY facility
in Physical Review C
Adlarson P
(2019)
Examination of the production of an isotensor dibaryon in the p p ? p p p + p - reaction
in Physical Review C
Adlarson P
(2018)
Spin Dependence of ? Meson Production in Proton-Proton Collisions Close to Threshold.
in Physical review letters
Adlarson P
(2018)
Total and differential cross sections of ?-production in proton-deuteron fusion for excess energies between Q = 13 MeV and Q = 81 MeV
in Physics Letters B
Adlarson P
(2020)
Three-nucleon dynamics in dp breakup collisions using the WASA detector at COSY-Jülich
in Physical Review C
Adlarson P
(2018)
Search for C violation in the decay ? ? p0e+e- with WASA-at-COSY
in Physics Letters B
Akondi C
(2019)
Experimental study of the $ \gamma p \rightarrow K^{0}\Sigma^{+}$, $ \gamma n \rightarrow K^{0} \Lambda$, and $ \gamma n \rightarrow K^{0} \Sigma^{0}$ reactions at the Mainz Microtron
in The European Physical Journal A
Bashkanov M
(2019)
Electromagnetic properties of the d * ( 2380 ) hexaquark
in Physical Review C
Bashkanov M
(2023)
On sequential single-pion production in double-pionic fusion
in Nuclear Physics A
Bashkanov M
(2019)
Deuteron photodisintegration by polarized photons in the region of the d?(2380)
in Physics Letters B
Bashkanov M
(2020)
A new possibility for light-quark dark matter
in Journal of Physics G: Nuclear and Particle Physics
Bashkanov M
(2023)
On Sequential Single-Pion Production in Double-Pionic Fusion
Bashkanov, M.
(2021)
Comment on "Sequential single-pion production explaining the dibaryon "d
*(2380)" peak"
in arXiv
Bono J
(2018)
First measurement of ?- polarization in photoproduction
in Physics Letters B
Celi M
(2024)
Destabilization of high-mass neutron stars by the emergence of d * -hexaquarks
in Physical Review D
Chandavar S
(2018)
Double K S 0 photoproduction off the proton at CLAS
in Physical Review C
CLAS Collaboration
(2019)
Modified structure of protons and neutrons in correlated pairs.
in Nature
Dieterle M
(2018)
Photoproduction of p 0 mesons off protons and neutrons in the second and third nucleon resonance regions
in Physical Review C
Fedotov G
(2018)
Measurements of the ? v p ? p ' p + p - cross section with the CLAS detector for 0.4 GeV 2 < Q 2 < 1.0 GeV 2 and 1.3 GeV < W < 1.825 GeV
in Physical Review C
Description | Strongly interacting particles are typically made of quarks. Until recently we believed that 2&3 quark configurations are the only options. A discovery of a first non-trivial hexaquark, the d*(2380) showed us that our options are more reach. According to our current understanding a six-quark state can be constructed in a two possible ways: a compact hexaquark and a diluted molecule made of two three-quark configurations. Our research showed that a d*(2380) is likely to be a compact state with a very large transition octupole magnetic moment. It was also shown that the d* might play a crucial role in neutron star equation of state or even contribute to a dark matter. |
Exploitation Route | One can use our constrains on multiquark dynamics to better understand the physics of early Universe and high density environments. It also help to predict the properties of other multiquark states |
Sectors | Other |
Description | Dr Mikhail Bashkanov |
Amount | £23,680 (GBP) |
Funding ID | ST/W005433/1 |
Organisation | Science and Technologies Facilities Council (STFC) |
Sector | Public |
Country | United Kingdom |
Start | 01/2022 |
End | 03/2022 |
Description | EIC Detector R&D |
Amount | £242,438 (GBP) |
Funding ID | ST/W004852/1 |
Organisation | Science and Technologies Facilities Council (STFC) |
Sector | Public |
Country | United Kingdom |
Start | 10/2021 |
End | 03/2024 |
Description | Elucidating Neutron Star Composition From Cutting-edge Hadron Physics (International Exchanges With Khon Kaen Thailand) |
Amount | £46,383 (GBP) |
Funding ID | IES\R3\203149 |
Organisation | The Royal Society |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 02/2021 |
End | 02/2023 |
Description | Elucidating the fundamental nature of hadrons with Particle Identification Detector |
Amount | £35,394 (GBP) |
Funding ID | ST/W005433/1 |
Organisation | Science and Technologies Facilities Council (STFC) |
Sector | Public |
Country | United Kingdom |
Start | 01/2022 |
End | 03/2022 |
Description | International Exchanges |
Amount | £11,320 (GBP) |
Funding ID | IES\R3\203149 |
Organisation | The Royal Society |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 03/2021 |
End | 12/2023 |
Title | High acceptance neutron polarymetry |
Description | Method allow the measurement of neutron polarisation in very large angular range and neutron energy ranges. Will be applied for the main measurements proposed in grant application to be performed in summer 2016. |
Type Of Material | Improvements to research infrastructure |
Provided To Others? | No |
Impact | Many baryon resonance decays have neutron in the final state, measuring polarisation of the outgoing neutron allow determination of the resonance properties. Verification of the method will be performed at upcoming summer 2016 beamtime. |
Title | high acceptance neutron detection and reconstruction |
Description | Develop a method of reliable use of detected neutrons in high acceptance calorimeter at Mainz for many-body reactions. |
Type Of Material | Improvements to research infrastructure |
Year Produced | 2015 |
Provided To Others? | Yes |
Impact | Use of detected neutrons instead of treating them as "unidentified particles" allows strong background suppression in reactions where neutrons are involved. Use of Kinematical Fit detected neutrons further improve detector resolution providing better accuracy in particle spectroscopy. |
Title | radioactive isotope production method for PET |
Description | A novel, potentially cheaper method to produce radioactive isotopes for Positron Emission tomography. The production system was build an prepared for testing |
Type Of Material | Technology assay or reagent |
Year Produced | 2018 |
Provided To Others? | No |
Impact | Positron tomography is a fast developing area in medicine. The limiting factor for further development is a cost (~1000 GBP per scan) which is largely determined by a price of PET isotopes (500 GBP per scan). Any improvement in PET isotope production has enormous influence to a billion pounds market of positron tomography and humongous effect on society extending affordability of modern medical techniques to larger fraction of population. |
Description | A2 collaboration (Crystal Ball, Mainz[Germany]) |
Organisation | Johannes Gutenberg University of Mainz |
Country | Germany |
Sector | Academic/University |
PI Contribution | 1) Analysis of the data 2) Detector maintenance and running (shift) 3) Construction of new detector components (Start construction of new polarymeter and particle identification detector as proposed in grant application) |
Collaborator Contribution | Detector maintenance, calibration, accelerator maintenance, target maintenance |
Impact | 1) New insight into nuclear and particle physics. 2) High quality polarisation measurements 3) Baryon spectroscopy |
Description | A2 collaboration (Crystal Ball, Mainz[Germany]) |
Organisation | National Institute for Nuclear Physics |
Department | National Institute for Nuclear Physics - Pavia |
Country | Italy |
Sector | Academic/University |
PI Contribution | 1) Analysis of the data 2) Detector maintenance and running (shift) 3) Construction of new detector components (Start construction of new polarymeter and particle identification detector as proposed in grant application) |
Collaborator Contribution | Detector maintenance, calibration, accelerator maintenance, target maintenance |
Impact | 1) New insight into nuclear and particle physics. 2) High quality polarisation measurements 3) Baryon spectroscopy |
Description | A2 collaboration (Crystal Ball, Mainz[Germany]) |
Organisation | Ruhr University Bochum |
Country | Germany |
Sector | Academic/University |
PI Contribution | 1) Analysis of the data 2) Detector maintenance and running (shift) 3) Construction of new detector components (Start construction of new polarymeter and particle identification detector as proposed in grant application) |
Collaborator Contribution | Detector maintenance, calibration, accelerator maintenance, target maintenance |
Impact | 1) New insight into nuclear and particle physics. 2) High quality polarisation measurements 3) Baryon spectroscopy |
Description | A2 collaboration (Crystal Ball, Mainz[Germany]) |
Organisation | University of Basel |
Country | Switzerland |
Sector | Academic/University |
PI Contribution | 1) Analysis of the data 2) Detector maintenance and running (shift) 3) Construction of new detector components (Start construction of new polarymeter and particle identification detector as proposed in grant application) |
Collaborator Contribution | Detector maintenance, calibration, accelerator maintenance, target maintenance |
Impact | 1) New insight into nuclear and particle physics. 2) High quality polarisation measurements 3) Baryon spectroscopy |
Description | A2 collaboration (Crystal Ball, Mainz[Germany]) |
Organisation | University of Bonn |
Country | Germany |
Sector | Academic/University |
PI Contribution | 1) Analysis of the data 2) Detector maintenance and running (shift) 3) Construction of new detector components (Start construction of new polarymeter and particle identification detector as proposed in grant application) |
Collaborator Contribution | Detector maintenance, calibration, accelerator maintenance, target maintenance |
Impact | 1) New insight into nuclear and particle physics. 2) High quality polarisation measurements 3) Baryon spectroscopy |
Description | A2 collaboration (Crystal Ball, Mainz[Germany]) |
Organisation | University of Glasgow |
Department | Physics and Astronomy Department |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | 1) Analysis of the data 2) Detector maintenance and running (shift) 3) Construction of new detector components (Start construction of new polarymeter and particle identification detector as proposed in grant application) |
Collaborator Contribution | Detector maintenance, calibration, accelerator maintenance, target maintenance |
Impact | 1) New insight into nuclear and particle physics. 2) High quality polarisation measurements 3) Baryon spectroscopy |
Description | EIC UG |
Organisation | Brookhaven National Laboratory |
Department | RIKEN-BNL Research Center |
Country | United States |
Sector | Academic/University |
PI Contribution | Simulations and design of the future EIC collider |
Collaborator Contribution | New detector simulations, polarised detector development, polarimeter studies |
Impact | new development of polarised detectors |
Start Year | 2021 |
Description | Elucidating Neutron Star Composition From Cutting-edge Hadron Physics (International Exchanges With Khon Kaen Thailand) |
Organisation | Khon Kaen University |
Country | Thailand |
Sector | Academic/University |
PI Contribution | Project 1417720: Elucidating Neutron Star Composition From Cutting-edge Hadron Physics (International Exchanges With Khon Kaen Thailand) new collaboration to implant our data on dibaryons into theoretical description of hexaquarks with subsequent use of them in a neutron star EOS studies. |
Collaborator Contribution | Providing experimental data and guiding theoretical calculations |
Impact | grant Project 1417720: Elucidating Neutron Star Composition From Cutting-edge Hadron Physics (International Exchanges With Khon Kaen Thailand) from Royal society. Publication is on its way |
Start Year | 2021 |
Description | Hall-B (Clas, Clas-12, [JLab, USA]) |
Organisation | JLab |
Sector | Private |
PI Contribution | 1) Data analysis 2) Simulations 3) Construction of new detector components |
Collaborator Contribution | 1) Data analysis 2) Simulations 3) Construction of new detector components |
Impact | 1) New spectroscopy data 2) Baryon and meson spectroscopy 3) high-energy photon beams |
Description | IOP public engagement event, physics master class |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | Nuclear physics public engagement activity |
Year(s) Of Engagement Activity | 2020 |
URL | https://events.iop.org/level-nuclear-physics-masterclass |
Description | KLong collaboration invited talk at Meson2021 conference |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Invited talk at the international conference Meson 2021 |
Year(s) Of Engagement Activity | 2021 |
Description | MOOC lecture "Neutron stars" |
Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Schools |
Results and Impact | A lecture as a part of Massive Online lecture course organised by the UoY |
Year(s) Of Engagement Activity | 2022 |
Description | Organisation of Exotic Hadron Spectroscopy workshop 2019, York. |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Fruitful discussions, a lot of new ideas and links |
Year(s) Of Engagement Activity | 2019 |
URL | https://www.iopconferences.org/iop/frontend/reg/thome.csp?pageID=884741&eventID=1401&language=1&CSPC... |
Description | South African nuclear physics summer school |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Undergraduate students |
Results and Impact | South African, nuclear physics summer school. Set of nuclear and medical physics lectures and master classes. |
Year(s) Of Engagement Activity | 2019 |
URL | http://www.unizulu.ac.za/unizulu-hosts-9th-tastes-of-nuclear-physics-conference/ |
Description | Strong2020 |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Organisation of Strong2020 workshop |
Year(s) Of Engagement Activity | 2021 |
URL | https://agenda.infn.it/event/27658/ |
Description | University of Manchester Seminar |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Postgraduate students |
Results and Impact | I was invited to make a general seminar at the University of Manchester to introduce our discoveries |
Year(s) Of Engagement Activity | 2018 |