{"schema":"https://ver.cy/schemas/card/1.0.0","id":"vr.tr.quark","code":"thing-q6718","url":"https://ver.cy/models/thing/q6718/","name":"quark","alternateNames":["sea quark"],"kind":"thing","status":"published","version":"0.1.0-research.1","language":"en","classifiers":{"family":"Thing Registry","category":"Physical world and living systems","entryKind":"thing","plane":"PHY","domain":["PHY.OBJ"],"industry":[],"navPath":"","tags":[],"facets":{}},"whatItIs":"A quark is an elementary fermion of the Standard Model that carries color charge, fractional electric charge and baryon number; quarks are subject to QCD confinement and constitute hadrons, except that top quarks decay before hadronization, and are not observed as isolated free particles.","purpose":"Enable an AI agent to recognise a quark description, assess what its inferred physical state supports, and select valid analyses or interaction models.","scope":{"in":["Quark flavour, particle or antiparticle designation, and identifying quantum numbers","Quark assignments within hadrons, scattering processes, simulations and strongly interacting media","Kinematics and mass parameters with their reference frame, scale and theoretical interpretation","Quark-specific production, interaction, hadronisation and decay constraints","Evidence supporting quark identification and limits on attributing observables to individual quarks"],"out":["Whole-hadron identity, spectrum and internal structure, owned by hadron models","Gluon and electroweak-boson identity and state","Jet reconstruction and detector operation as independently managed systems","Bulk thermodynamic properties of quark-gluon plasma","Complete collision-event descriptions and accelerator operation"],"boundaries":[]},"distinguishingFeatures":["Require a supported assignment to up, down, strange, charm, bottom or top flavour; 'parton' alone does not distinguish a quark from a gluon. [CERN quark glossary](https://opendata.cern.ch/glossary/Quark)","Check fractional electric charge against flavour and particle or antiparticle designation: quarks have +2/3 or -1/3 in elementary-charge units, with opposite signs for antiquarks. [CERN quark glossary](https://opendata.cern.ch/glossary/Quark)","Require consistency with a spin-1/2 colour-triplet quark, or colour-antitriplet antiquark, rather than a colourless lepton or a spin-1 gluon.","Distinguish the inferred quark from its containing hadron or associated jet; an isolated detector track is insufficient evidence for a free quark. [CERN ALICE overview](https://home.cern/science/experiments/alice/)"],"structure":{"bundles":[{"id":"flavour-and-quantum-identity","name":"Flavour and quantum identity","description":"Record what makes an assignment a particular quark species rather than another particle.","layers":[{"id":"flavour-and-conjugation","name":"Flavour and conjugation","description":"Separate species identity from particle or antiparticle designation.","findings":[{"id":"supported-flavour-assignment","name":"Supported flavour assignment","description":"Record a resolved flavour or explicit alternatives, together with whether the assignment denotes a quark or antiquark.","questions":[{"text":"Which quark flavour and particle or antiparticle designation are asserted, and which remain unresolved?","id":"supported-flavour-assignment-q01","kind":"definition"},{"text":"Does this assignment come from a theoretical species definition, generator ancestry or experimental flavour evidence?","id":"supported-flavour-assignment-q02","kind":"provenance"}]}]},{"id":"quantum-number-consistency","name":"Quantum-number consistency","description":"Check the identifying quantum numbers without confusing intrinsic properties with measured proxies.","findings":[{"id":"compatible-charge-spin-and-colour","name":"Compatible charge, spin and colour","description":"Require a consistent charge, spin and colour representation, while distinguishing spin-state estimates and colour-flow conventions from species properties.","questions":[{"text":"Are electric charge, spin and colour representation consistent with the proposed flavour and conjugation?","id":"compatible-charge-spin-and-colour-q01","kind":"definition"},{"text":"Which stated properties are inferred from identity, and which have independently measured estimators?","id":"compatible-charge-spin-and-colour-q02","kind":"measurement"},{"text":"Would the same evidence also support a lepton, gluon or composite-hadron interpretation?","id":"compatible-charge-spin-and-colour-q03","kind":"boundary"}]}]}]},{"id":"confinement-and-description-context","name":"Confinement and description context","description":"Record where a quark description applies and what its containing or associated system permits an agent to infer.","layers":[{"id":"hadronic-and-medium-context","name":"Hadronic and medium context","description":"Locate the quark description within a hadron or interacting medium.","findings":[{"id":"constituent-role-and-environment","name":"Constituent role and environment","description":"Record whether the description concerns valence content, sea contributions or an effective medium excitation, rather than assigning every context a persistent individual constituent.","questions":[{"text":"Is the quark described as valence content, a sea contribution or an excitation in a strongly interacting medium?","id":"constituent-role-and-environment-q01","kind":"definition"},{"text":"Which hadron or medium model supplies the environment and the approximation used?","id":"constituent-role-and-environment-q02","kind":"provenance"},{"text":"Does the description support an individual quark state, or only flavour content or a statistical distribution?","id":"constituent-role-and-environment-q03","kind":"boundary"}]}]},{"id":"partonic-description-limits","name":"Partonic description limits","description":"Bound the interpretation of quarks represented in calculations and event records.","findings":[{"id":"parton-stage-and-identity-limits","name":"Parton stage and identity limits","description":"Distinguish hard-process and shower assignments from observable final particles, and retain the conventions behind any ancestry relation.","questions":[{"text":"At which calculation or generator stage is this quark assignment defined?","id":"parton-stage-and-identity-limits-q01","kind":"definition"},{"text":"What resolution scale, factorisation assumptions or event-record conventions make that assignment meaningful?","id":"parton-stage-and-identity-limits-q02","kind":"boundary"},{"text":"May an agent follow the assignment across stages, or must it preserve a probabilistic or convention-dependent association?","id":"parton-stage-and-identity-limits-q03","kind":"action"}]}]}]},{"id":"kinematics-and-mass-interpretation","name":"Kinematics and mass interpretation","description":"Make quantitative quark-state assertions interpretable and comparable.","layers":[{"id":"momentum-and-virtuality","name":"Momentum and virtuality","description":"Qualify assigned kinematics by reference frame and modelling level.","findings":[{"id":"qualified-four-momentum","name":"Qualified four-momentum","description":"Record momentum, uncertainty and any on-shell or virtuality assumptions without silently substituting jet or hadron kinematics.","questions":[{"text":"What four-momentum is assigned, in which frame, and with what uncertainty or distribution?","id":"qualified-four-momentum-q01","kind":"measurement"},{"text":"Is it a parton-level value, a reconstructed estimate or a proxy taken from an associated jet or hadron?","id":"qualified-four-momentum-q02","kind":"provenance"},{"text":"Which on-shell or off-shell assumptions constrain the use of this momentum?","id":"qualified-four-momentum-q03","kind":"boundary"}]}]},{"id":"mass-definition-and-scale","name":"Mass definition and scale","description":"Preserve the meaning of a quoted quark mass.","findings":[{"id":"interpretable-mass-parameter","name":"Interpretable mass parameter","description":"Attach the mass definition and relevant scale to a quoted value, preserving distinctions between field-theory, effective and generator parameters.","questions":[{"text":"Which mass definition is used, with what value, uncertainty, scheme and applicable scale?","id":"interpretable-mass-parameter-q01","kind":"measurement"},{"text":"Is this a running mass, pole mass, constituent-model parameter or generator parameter?","id":"interpretable-mass-parameter-q02","kind":"definition"},{"text":"What justified conversion or matching procedure is required before comparing it with another mass value?","id":"interpretable-mass-parameter-q03","kind":"action"}]}]}]},{"id":"interaction-and-fate","name":"Interaction and fate","description":"Describe which quark processes can be evaluated and how the quark assignment terminates or changes.","layers":[{"id":"production-and-flavour-transitions","name":"Production and flavour transitions","description":"Constrain proposed production and interaction channels.","findings":[{"id":"channel-admissibility","name":"Channel admissibility","description":"Evaluate proposed channels using the stated interaction model, initial state, available energy and relevant conservation constraints.","questions":[{"text":"Which production, scattering or flavour-changing channel is proposed, and under which interaction model?","id":"channel-admissibility-q01","kind":"definition"},{"text":"Are its charge balance, energy requirements and other applicable quantum-number constraints satisfied?","id":"channel-admissibility-q02","kind":"boundary"},{"text":"Which calculation and parameter inputs are needed before an agent can estimate a rate or branching probability?","id":"channel-admissibility-q03","kind":"action"}]}]},{"id":"hadronisation-and-decay","name":"Hadronisation and decay","description":"Distinguish hadron formation from quark-level decay and reconstructed descendants.","findings":[{"id":"flavour-dependent-fate","name":"Flavour-dependent fate","description":"Record the applicable hadronisation or decay treatment; top quarks decay before hadronising and require a distinct reconstruction path. [ATLAS top-quark overview](https://atlas.cern/updates/feature/top-quark)","questions":[{"text":"Does the assigned flavour and environment require hadronisation modelling, quark-level decay modelling or an explicitly coupled treatment?","id":"flavour-dependent-fate-q01","kind":"boundary"},{"text":"Does a quoted lifetime or decay width belong to the quark description or to a containing hadron?","id":"flavour-dependent-fate-q02","kind":"measurement"},{"text":"Which descendants or hadronisation products may be linked to this assignment, with what modelling uncertainty?","id":"flavour-dependent-fate-q03","kind":"action"}]}]}]},{"id":"observable-evidence-and-inference","name":"Observable evidence and inference","description":"Connect quark assertions to measurable signatures and control how strongly an agent may act on them.","layers":[{"id":"signatures-and-alternatives","name":"Signatures and alternatives","description":"Record the observables and competing explanations behind an assignment.","findings":[{"id":"evidence-for-quark-assignment","name":"Evidence for quark assignment","description":"Identify the measured signatures supporting a quark or flavour interpretation, retaining backgrounds and ambiguity between quark and gluon origins.","questions":[{"text":"Which measured signatures support the assignment, such as displaced vertices, identified hadrons, decay reconstruction or scattering distributions?","id":"evidence-for-quark-assignment-q01","kind":"measurement"},{"text":"Which dataset, analysis and reconstruction procedure produced those signatures?","id":"evidence-for-quark-assignment-q02","kind":"provenance"},{"text":"Which alternative flavours, gluon processes or hadronic backgrounds remain compatible with the evidence?","id":"evidence-for-quark-assignment-q03","kind":"boundary"}]}]},{"id":"calibration-and-permitted-use","name":"Calibration and permitted use","description":"Translate evidence quality into justified analytical actions.","findings":[{"id":"assignment-strength-and-use","name":"Assignment strength and use","description":"Preserve tagging calibration, selection dependence and model uncertainty so that a candidate label does not become an unjustified certainty.","questions":[{"text":"What efficiencies, mistag rates, uncertainty estimates and validation domain accompany the assignment?","id":"assignment-strength-and-use-q01","kind":"measurement"},{"text":"Is a reported score a calibrated probability, a discriminant or a generator label?","id":"assignment-strength-and-use-q02","kind":"definition"},{"text":"Does the evidence justify selecting a flavour-specific analysis, retaining several hypotheses or withholding a resolved assignment?","id":"assignment-strength-and-use-q03","kind":"action"}]}]}]},{"id":"evidence-and-external-alignment","name":"Evidence and external alignment","description":"What the world already says about this thing, gathered so the model can be checked against it.","layers":[{"id":"reported-evidence","name":"Reported evidence","description":"Findings from the breadth pass, kept separate from the structural claims.","findings":[{"id":"evidence-kinds","name":"Kinds and varieties","description":"Reported by the breadth pass; each item needs checking against its source before it becomes normative.","questions":[{"text":"Which of these kinds and varieties hold for the sense of quark this model covers, and on what evidence?","id":"evidence-kinds-q01","kind":"provenance"}]}]}]}]},"agentConduct":{"may":["Describe quarks and their properties from established physics sources.","Analyse particle physics data the agent is authorized to work with."],"mustNot":["Present speculative quark theories or unconfirmed states as established.","Selectively drop data to fit a claimed discovery.","Use the word quark to sell pseudo-scientific products or health claims."],"requiresHuman":["Announcing or endorsing a claimed discovery to the public."]},"ethics":{"considerations":["Fundamental physics depends on careful, honest data analysis.","Scientific terms are misused to lend authority to quackery."],"affectedParties":["Researchers","Students","The public"]},"owners":{"steward":"Nobody owns them; particle physics data bodies curate their measured properties.","roles":[],"masterSystems":["Particle physics data reviews"]},"relations":[{"target":"Q52234516","type":"parent","note":"registry parent class"},{"target":"Q587553","type":"parent","note":"registry parent class"}],"interaction":{"identity":{"applicability":"required","items":["Vercy registry: vr.tr.quark","Wikidata: Q6718 (https://www.wikidata.org/wiki/Q6718)"]},"properties":{"applicability":"required","items":["Flavour assignment: up | down | strange | charm | bottom | top | unresolved; retain competing hypotheses","Particle or antiparticle assignment: quark | antiquark | unresolved","Electric charge: Elementary-charge units e; distinguish inferred quantum-number assignment from a measured estimator","Spin description: Spin quantum number 1/2; optional polarisation or helicity description with basis and uncertainty","Colour description: Triplet | antitriplet; optional simulation colour-flow labels with convention","Physical or modelling context: Hadron constituent | hard-process parton | shower parton | medium excitation | reconstructed hypothesis","Containing or associated system: Links to hadron, collision process, medium, jet or decay hypothesis; specify relation type","Four-momentum assignment: Energy in GeV and momentum components in GeV/c; frame, reconstruction level and uncertainty required","Mass parameter: GeV/c^2; mass definition, renormalisation scheme and scale where applicable","Inference status: Species property | theoretical assignment | generator record | experimentally inferred candidate; confidence with calibration context"]},"recognition":{"applicability":"not-applicable","items":[]},"capabilities":{"applicability":"required","items":["Check a proposed quark identity against flavour, charge, spin and colour representation.","Associate a quark hypothesis with hadron content, a hard process or reconstructed decay evidence.","Compare kinematic or mass estimates only after reconciling definitions, scales and uncertainties.","Evaluate proposed production and transition channels against conservation laws and interaction assumptions.","Select a context-appropriate calculation, simulation or tagging method and report its applicability limits.","Revise or reject an assignment when evidence cannot distinguish a quark from alternative partonic or hadronic explanations."]},"hazards":{"applicability":"required","items":["Overclaimed results that later fail to replicate."]},"interfaces":{"applicability":"not-applicable","items":[]},"context":{"applicability":"required","items":["Quarks are used in particle physics to describe the constituents and interactions of hadrons, including protons and neutrons.","Their properties are investigated through scattering, collision products and theoretical calculations rather than direct observation of isolated particles."]}},"sources":[{"title":"Quark (Review of Particle Physics)","url":"https://pdg.lbl.gov/","note":"Masses, charges, generations, and Standard Model quantum numbers of the six quark flavors."},{"title":"The Standard Model - quarks","url":"https://home.cern/science/physics/standard-model","note":"CERN public description of quarks as confined constituents of hadrons."},{"title":"Wikidata item Q6718: quark","url":"https://www.wikidata.org/wiki/Q6718","note":"identity and sense of the item"},{"title":"Wikipedia: Quark","url":"https://en.wikipedia.org/wiki/Quark","note":"general description of the item"}],"openQuestions":["Does the registry intend antiquarks to be represented within vr.tr.quark or through a neighbouring entry linked by charge conjugation?","Which levels of description must the first implementation support: species properties, event-level partons, hadron constituents or medium excitations?","Which authoritative mass references, schemes and conversion procedures should govern comparisons for each flavour?","What evidence and calibration thresholds should permit an agent to promote a flavour candidate to an accepted assignment in each supported analysis context?","How should the model represent colour correlations and ambiguous parton ancestry without implying directly observable colour labels or persistent individual-quark identity?"],"resources":{"spec":"/models/things/publications/thing-q6718/spec.json"},"provenance":{"origin":"thing registry research (pass 2)","builtFrom":["models/things/publications/thing-q6718/spec.json"],"providers":["Codex","Grok"],"researchStatus":"unreviewed","generatedAt":"2026-09-07T11:49:08Z","builder":"tools/build_cards.py@1.0.0"},"completeness":{"sections":{"classifiers":"filled","whatItIs":"filled","purpose":"filled","distinguishingFeatures":"filled","structure":"filled","agentConduct":"filled","ethics":"filled","owners":"filled","relations":"filled","interaction.identity":"filled","interaction.properties":"filled","interaction.recognition":"not-applicable","interaction.capabilities":"filled","interaction.hazards":"filled","interaction.interfaces":"not-applicable","interaction.context":"filled","sources":"filled"},"notes":{"_gate":"Published through the thing publication gate 1.0 on 2026-10-07T12:16:34+00:00: completeness 1.00; sense: Wikidata description; 4 live sources; review by codex: pass","interaction.interfaces":"No specific standard, law or official classification governs quarks themselves as natural elementary particles.","interaction.recognition":"Quarks have no directly visible identifying features and are inferred through experimental measurements."},"score":1.0}}