Related Experiment Video
Updated: Jul 20, 2026
08:53
Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
New physics searches at the BESIII experiment
Shenjian Chen1, Stephen Lars Olsen2
1School of Physics, Nanjing University, Nanjing 210093, China.
National Science Review
|April 6, 2022
Summary
The Standard Model (SM) of particle physics has shortcomings. Experiments at BESIII search for new physics beyond the SM by testing rare processes and looking for new particles.
Area of Science:
- Particle Physics
- Beyond Standard Model (BSM) Physics
Background:
- The Standard Model (SM) is the prevailing theory for fundamental particles and interactions.
- Despite its success, the SM has limitations, including unexplained phenomena like dark matter and matter-antimatter asymmetry.
Purpose of the Study:
- To review highlights of searches for new physics beyond the Standard Model (BSM) conducted at BESIII.
- To investigate phenomena not explained by the current Standard Model.
Main Methods:
- Measuring the rates of processes predicted as forbidden or rare by the SM.
- Searching for hypothetical particles, such as dark photons.
- Conducting precision tests of SM predictions.
- Investigating violations of discrete symmetries (C and CP).
Main Results:
- Highlights from BESIII's ongoing search for BSM physics are presented.
- The study reviews various experimental approaches to uncover physics beyond the Standard Model.
Conclusions:
- Searches for BSM physics are crucial for developing a more complete theory.
- BESIII contributes to the search for new physics despite operating below the energy frontier.
Related Concept Videos
01:17The Scope of Physics
Physics is concerned with the interactions of energy, matter, space, and time, in order to discover the underlying mechanisms that underpin all phenomena. The word "physics" comes from the Greek word "phúsis", which means nature. Physics seeks to comprehend the natural world around us at its most fundamental level. It emphasizes the use of quantitative laws to do this, which could be valuable in other fields that want to push the performance boundaries of present technologies.
Physics knowledge...
Physics knowledge...
01:06Nuclear Overhauser Enhancement (NOE)
Irradiation of a spin-active nucleus causes an increase or decrease in the signal intensity of neighboring nuclei that are not necessarily chemically bonded or involved in J-coupling. This phenomenon, called the nuclear Overhauser enhancement (NOE), results from through-space interactions between the nuclear spins. The NOE effect decreases with increasing internuclear distance and is generally not observed beyond 4 angstroms. In NOE, dipole-dipole interactions between neighboring spin-active...
01:30Electromagnetic Waves in Matter
Electromagnetic waves can travel in the vacuum as well as in matter. For example light, which is an electromagnetic wave, can travel through air, water, or glass.
Consider the electromagnetic wave passing through a dielectric medium. In such a case, Maxwell's equations get modified. In Ampere's law, ε0 , the dielectric permittivity of free space is replaced with ε, the permittivity of dielectric. Also, the vacuum permeability μ0 is replaced by the permeability of the medium, μ.
Furthermore, the...
Consider the electromagnetic wave passing through a dielectric medium. In such a case, Maxwell's equations get modified. In Ampere's law, ε0 , the dielectric permittivity of free space is replaced with ε, the permittivity of dielectric. Also, the vacuum permeability μ0 is replaced by the permeability of the medium, μ.
Furthermore, the...
01:19Thomson's e/m Experiment
In a beam of charged particles created by a heated cathode, the particles move at different speeds. However, many applications need a beam with uniform particle speeds. An arrangement known as a velocity selector uses electric and magnetic fields to pick particles with a particular speed from the beam.
A particle with charge q, speed v, and mass m enters an area from the top, where the magnetic and electric fields are perpendicular both to the particle's motion and to one another. The magnetic...
A particle with charge q, speed v, and mass m enters an area from the top, where the magnetic and electric fields are perpendicular both to the particle's motion and to one another. The magnetic...
01:22Atomic Emission Spectroscopy: Instrumentation
The instrumentation of atomic emission spectrometry (AES) involves various components, including atomization devices that convert samples into gas-phase atoms and ions. There are two main types of atomization devices: continuous and discrete atomizers. Continuous atomizers, like plasmas and flames, introduce samples in a constant stream, while discrete atomizers inject individual samples using syringes or autosamplers. The most common discrete atomizer is the electrothermal atomizer.
01:30Atomic Emission Spectroscopy: Interference
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...