14 DAY TRIAL // A decade has passed since physicists postulated the existence of dark matter and dark energy in order to complement the missing matter in the universe; however, its constituents are still eluding detection. Aside the weakly interacting neutrino particles described in the Standard Model of the universe, scientists are now proposing a new particle constituent of dark matter, in the form of axion elementary particles, not yet discovered in real life experiments.
Axions are hypothetical elementary particles believed to have a mass of about a few mili-electronvolts, making it an incredible 500 million times lighter than the electrons, have no spin and present weak interactions towards regular matter. The experiment was conducted at the Farmi National Accelerator Laboratory by William Wester with the help of physicists from the University of Michigan. William Wester: "It is incredibly hard detecting such particles in the mili-eV range in controlled conditions, but the fact is that we are detecting them every day just by pointing a telescope towards space".
Additionally, because they are so hard to detect, there are serious doubts whether these particles can really exist in the fabric of space-time. However, things do not seem as harsh as one might imagine, as previously physicists detected, with the help of the PVLAS experiment, what seems to be a weak signal generated by an axion elementary particle. In order to confirm the result, the Fermi team had to imply the use of innovative settings such as Tevatron magnets which are more powerful, thus more efficient, in the milli-eV range.
Wester writes that during the experiment, once the magnetic field has been established, a laser beam is immediately fired through the middle, in the hope that the powerful magnetic field would be able to convert some of the emitted photons into axion particles. The beam is fired at a solid target, which absorbs or reflects the photon particles and lets the axion particles pass without being deviated, to be detected on the other side of the target.
Four configurations have been used during the experiment, plus two polarization patterns, vertical and horizontal, albeit axions remained hidden from the keen eyes of the detector. Wester's colleague, Aaron Chou, on the other hand, believes that the magnetic fields of the accelerator are not powerful enough for such an experiment. Secondly, the extracted data suggests that the Fermi team might have instead found what physicists call a chameleon particle, a low mass particle while in low energy density, and large mass when placed in a high energy density.