Related Experiment Video
Updated: Jun 26, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Search for third generation scalar leptoquarks decaying into taub
V M Abazov1, B Abbott, M Abolins
1Joint Institute for Nuclear Research, Dubna, Russia.
Physical Review Letters
|December 31, 2008
Summary
Researchers searched for third-generation leptoquarks (LQ3) at the Fermilab Tevatron. A lower limit of 210 GeV was set for the mass of a scalar LQ3 decaying to a b quark and tau lepton.
Area of Science:
- High Energy Physics
- Particle Physics
- Collider Physics
Background:
- Leptoquarks are hypothetical elementary particles that couple to both leptons and quarks.
- Third-generation leptoquarks (LQ3) are predicted by some extensions to the Standard Model.
- Searches for leptoquarks are crucial for testing new physics beyond the Standard Model.
Purpose of the Study:
- To search for evidence of third-generation leptoquarks (LQ3) in proton-antiproton collisions.
- To set limits on the mass of scalar LQ3 states decaying into a b quark and a tau lepton.
Main Methods:
- Utilized 1.05 fb⁻¹ of data collected by the D0 detector at the Fermilab Tevatron Collider.
- Operated at a center-of-mass energy of sqrt(s) = 1.96 TeV.
- Analyzed data for signatures consistent with LQ3 production and decay.
Main Results:
- No significant excess of events attributable to LQ3 was observed.
- A 95% confidence level (C.L.) lower limit was set on the mass of a scalar LQ3 state.
- The lower limit on the scalar LQ3 mass was determined to be 210 GeV.
Conclusions:
- The absence of LQ3 signals in this dataset places constraints on theories predicting their existence.
- This result contributes to the ongoing search for new physics phenomena at high-energy colliders.
- Further searches with increased integrated luminosity and improved analysis techniques are warranted.
Related Concept Videos
03:20Nuclear Transmutation
Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with another particle. The first manmade nucleus was produced in Ernest Rutherford’s laboratory in 1919 by a transmutation reaction, the bombardment of one type of nuclei with other nuclei or with neutrons. Rutherford bombarded nitrogen-14 atoms with high-speed α particles from a natural radioactive isotope of radium and observed protons being...
03:18Nuclear Stability
Protons and neutrons, collectively called nucleons, are packed together tightly in a nucleus. With a radius of about 10−15 meters, a nucleus is quite small compared to the radius of the entire atom, which is about 10−10 meters. Nuclei are extremely dense compared to bulk matter, averaging 1.8 × 1014 grams per cubic centimeter. If the earth’s density were equal to the average nuclear density, the earth’s radius would be only about 200 meters.
To hold positively charged protons together in the...
To hold positively charged protons together in the...
01:14Atomic Nuclei: Nuclear Spin State Population Distribution
Near absolute zero temperatures, in the presence of a magnetic field, the majority of nuclei prefer the lower energy spin-up state to the higher energy spin-down state. As temperatures increase, the energy from thermal collisions distributes the spins more equally between the two states. The Boltzmann distribution equation gives the ratio of the number of spins predicted in the spin −½ (N−) and spin +½ (N+) states.
01:06Scalar and Vector Triple Products
Two vectors can be multiplied using a scalar product or a vector product. The resultant of a scalar product is scalar, while with vector products, the resultant is a vector. These rules of the scalar or vector product between two vectors can be applied to multiple vectors to obtain meaningful combinations. The scalar triple product is the dot product of a vector with the cross product of two vectors.
The scalar triple product is the dot product of a vector with the cross product of two vectors.
The scalar triple product is the dot product of a vector with the cross product of two vectors.
02:10Additional Subnuclear Structures
The eukaryotic nucleus is a double membrane-bound organelle that contains nearly all of the cell’s genetic material in the form of chromosomes. It is rightly called the “brain” of the cell as it shoulders the responsibility of responding to various physiological processes, stress, altered metabolic conditions, and other cellular signals.
The nucleus contains many membrane-less subnuclear organelles or nuclear bodies, such as nucleoli, Cajal bodies, speckles, paraspeckles, etc. These nuclear...
The nucleus contains many membrane-less subnuclear organelles or nuclear bodies, such as nucleoli, Cajal bodies, speckles, paraspeckles, etc. These nuclear...
02:10Additional Subnuclear Structures
The eukaryotic nucleus is a double membrane-bound organelle that contains nearly all of the cell’s genetic material in the form of chromosomes. It is rightly called the “brain” of the cell as it shoulders the responsibility of responding to various physiological processes, stress, altered metabolic conditions, and other cellular signals.
The nucleus contains many membrane-less subnuclear organelles or nuclear bodies, such as nucleoli, Cajal bodies, speckles, paraspeckles, etc. These nuclear...
The nucleus contains many membrane-less subnuclear organelles or nuclear bodies, such as nucleoli, Cajal bodies, speckles, paraspeckles, etc. These nuclear...