V_td
E815592
V_td is a complex element of the Cabibbo–Kobayashi–Maskawa (CKM) quark mixing matrix that quantifies the weak-interaction transition strength between top and down quarks and plays a key role in flavor-changing processes and CP violation in the Standard Model.
All labels observed (1)
| Label | Occurrences |
|---|---|
| V_td canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T9689294 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: V_td Context triple: [Cabibbo–Kobayashi–Maskawa matrix, hasElement, V_td]
-
A.
VTZ
VTZ is the IATA airport code for Visakhapatnam Airport, a major domestic and limited international airport serving the coastal city of Visakhapatnam in Andhra Pradesh, India.
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B.
VT
VT is the standard two-letter postal abbreviation used to represent the U.S. state of Vermont.
-
C.
VT
VT is the vehicle registration code used on license plates for vehicles registered in the Province of Viterbo in Italy.
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D.
VT
VT is the commonly used abbreviation for Virginia Tech, a major public research university in Blacksburg, Virginia.
-
E.
TAD
TAD is the OECD’s Trade and Agriculture Directorate, which develops international policies and analysis on global trade, agriculture, and related economic issues.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: V_td Target entity description: V_td is a complex element of the Cabibbo–Kobayashi–Maskawa (CKM) quark mixing matrix that quantifies the weak-interaction transition strength between top and down quarks and plays a key role in flavor-changing processes and CP violation in the Standard Model.
-
A.
VTZ
VTZ is the IATA airport code for Visakhapatnam Airport, a major domestic and limited international airport serving the coastal city of Visakhapatnam in Andhra Pradesh, India.
-
B.
VT
VT is the standard two-letter postal abbreviation used to represent the U.S. state of Vermont.
-
C.
VT
VT is the vehicle registration code used on license plates for vehicles registered in the Province of Viterbo in Italy.
-
D.
VT
VT is the commonly used abbreviation for Virginia Tech, a major public research university in Blacksburg, Virginia.
-
E.
TAD
TAD is the OECD’s Trade and Agriculture Directorate, which develops international policies and analysis on global trade, agriculture, and related economic issues.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
CKM matrix element
ⓘ
complex number ⓘ quark mixing parameter ⓘ |
| affects |
indirect CP violation in B_d systems
ⓘ
rates of top quark decays involving down quarks ⓘ |
| appearsIn |
W boson couplings to quarks
ⓘ
charged-current weak interactions ⓘ down-type quark flavor-changing amplitudes ⓘ effective Hamiltonians for flavor-changing neutral currents via loops ⓘ top quark decay amplitudes ⓘ |
| constrainedBy |
B meson mixing measurements
ⓘ
B_d–B̄_d oscillations ⓘ global CKM fits ⓘ rare B meson decays ⓘ |
| contributesTo |
CP violation in the Standard Model
ⓘ
flavor-changing processes ⓘ |
| definedIn | quark flavor eigenstate to mass eigenstate transformation ⓘ |
| dependsOn | Wolfenstein parameters ρ and η ⓘ |
| describes | weak-interaction transition strength between top and down quarks ⓘ |
| enters |
box diagrams for B_d mixing
ⓘ
penguin diagrams involving top quarks ⓘ |
| governs | t → d W^+ vertex strength ⓘ |
| hasComponent |
imaginary part of V_td
ⓘ
real part of V_td ⓘ |
| hasMagnitude | small compared to V_ud and V_tb ⓘ |
| hasProperty |
CP-violating phase contribution
ⓘ
complex phase ⓘ |
| hasQuarkTransition |
t → d
ⓘ
top quark to down quark ⓘ |
| hasRole | source of flavor mixing between third and first quark generations ⓘ |
| hasTheoreticalUncertainty | from hadronic matrix elements and lattice QCD inputs ⓘ |
| isElementOf | 3×3 unitary CKM matrix ⓘ |
| measuredBy |
flavor physics experiments at B factories
ⓘ
high-energy collider experiments ⓘ |
| namedAfter | indices t and d for top and down quarks ⓘ |
| parameterizedBy |
Wolfenstein parametrization
ⓘ
linked to:
Wolfenstein parameterization
|
| partOf |
Cabibbo–Kobayashi–Maskawa matrix
ⓘ
Standard Model of particle physics ⓘ
linked to:
Standard Model
|
| playsKeyRoleIn | precision tests of the Standard Model flavor sector ⓘ |
| relatedTo |
V_cd
ⓘ
V_tb ⓘ V_ts ⓘ V_ud ⓘ |
| satisfies | CKM unitarity constraints ⓘ |
| symbolOf | CKM matrix element in the first column and third row ⓘ |
| testedBy | consistency of CKM unitarity ⓘ |
| usedIn | unitarity triangle construction ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: V_td Description of subject: V_td is a complex element of the Cabibbo–Kobayashi–Maskawa (CKM) quark mixing matrix that quantifies the weak-interaction transition strength between top and down quarks and plays a key role in flavor-changing processes and CP violation in the Standard Model.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.