Physicists Detect New Particle Which is a Dark Matter Candidate!

^{Credit: Nature}

^{By Amal Pushp, Affiliate Physicist at Resonance Science Foundation}

The standard model of particle physics is currently the best theory out there describing the fundamental constituents of nature. The model accurately describes the basic forces and their interactions with gravity being the only exception.

Despite the successes that the model boasts of, there are certain shortcomings of the theory that scientists around the world are trying to address and resolve. One of the key motivations is to find out the foundational building blocks of the so called Dark matter and Dark Energy which are believed to be made up of new unknown and undiscovered particles.

Recently, an interdisciplinary team of scientists led by physicists from Boston college in the US announced that they have discovered a new particle – or previously undetectable quantum excitation – known as the axial Higgs mode, a magnetic relative of the Higgs boson.

“The detection a decade ago of the long-sought Higgs Boson became central to the understanding of mass. Unlike its parent, axial Higgs mode has a magnetic moment, and that requires a more complex form of the theory to explain its properties”, said Boston College Professor of Physics Kenneth Burch, a lead co-author of the paper that reported the discovery [1].

'Theories that predicted the existence of such a mode have been invoked to explain “dark matter” the nearly invisible material that makes up much of the universe, but only reveals itself via gravity', Burch said.

It is well known that the Higgs Boson, a quantum particle that is the excitation of the Higgs field, was discovered by colliding particles in the CERN-based particle accelerator, the LHC. However, as interesting as it sounds, the new particle was discovered in table top experiments studying RTe₃, or rare-earth tritelluride, at room temperature. The discovery of particles in such a setup is not an everyday scenario and this makes the experiment a rare one!

In order to reveal the nature of this particle, the team also used scattering of light wherein a laser beam is shined on the material and the radiation can change color as well as polarization. The change in color results primarily from light producing the Higgs Boson in the material, while the polarization is sensitive to the symmetry components of the particle. Furthermore, the axial Higgs could be generated with different components – such as one absent magnetism, or a component pointing up and this is made possible through proper choice of the polarization states of the incident and transmitted light.

The existence of this particle was predicted in the high-energy particle physics papers as a candidate for dark matter [2]. Now the surprising experimental detection of the same would prove to be revolutionary as it would be helpful in comparing the data with the current knowledge of the dark matter. The particle could also be recreated in other systems and under different conditions and this could be a viable exploration in the near future. The experimental techniques adopted by the team that discovered the particle could also be utilized in different areas of research, as pointed out by the lead co-author of the study Kenneth Burch.

Thus, it is only a matter of time before would reveal whether the axial Higgs boson is the true component of the mysterious and elusive dark matter or not. Until then, theoretical refinements of existing models and tests of new experiments would continue.

References

[1] Kenneth Burch, Axial Higgs Mode Detected by Quantum Pathway Interference in RTe3, Nature (2022). DOI: 10.1038/s41586-022-04746-6

[2] Jonathan L. Feng, Dark Matter Candidates from Particle Physics and Methods of Detection, Annual Reviews of Astronomy and Astrophysics 48: 495, 2010.