Researchers from the autonomous institution, Raman Research Institute (RRI), in Bengaluru, have made significant strides in demystifying the antimatter equivalent of electrons, known as positrons. Their research has further shed light on the intriguing phenomenon termed as ‘Positron Excess’.
Understanding Anti-Matter
Opposite to normal matter is antimatter, which interestingly, comprises of sub-atomic particles with properties differing from those in normal matter. Matter, composed of atoms, includes basic units of chemical elements like hydrogen, helium, or oxygen. These atoms are structured into three particles: protons, neutrons, and electrons.
The Positron Particle
Claimed to be discovered in the year 1932, a positron is a subatomic particle bearing a close resemblance to an electron in terms of mass. However, the charge it carries is positive, as opposed to the negative charge on an electron.
The Positron Excess Phenomena
Over the years, scientists have been intrigued by the excessive presence of high-energy particles of positrons. Astronomical observations have revealed positrons possessing an energy exceeding 10 giga-electron volts (GeV). Putting this into perspective, this particular energy capacity aligns with that of a positively charged electron powered by a 10,000,000,000 volt battery. The disparity arises when considering positrons with energy over 300 GeV, which is significantly lower than astronomical predictions. This peculiar behavior of positrons within the 10 to 300 GeV range, is what led to the term ‘positron excess’.
RRI’s In-depth Study on Cosmological Processes
Home to colossal clouds of molecular hydrogen, the Milky Way is the birthplace of new stars. Cosmic rays originating from supernovae explosions traverse through these clouds before reaching Earth. In these clouds, cosmic rays intermingle with the molecular hydrogen, transmuting into other cosmic rays, gaining and losing energy in the process.
RRI conducted a thorough examination of these astrophysical procedures employing a proprietary computer code. This code took into account 1638 molecular hydrogen clouds within the Milky Way, observed by other astronomers across various electromagnetic spectrum wavelengths.
RRI’s Computational Code
By following a comprehensive catalog of ten molecular clouds near our Sun, RRI was able to derive the number of giga-electron volt cosmic rays. This data provided insight into the excess number of positrons reaching Earth. The computer code successfully replicated the documented number of positrons at giga-electron volt energies, encompassing the positron excess and accurately modeling the spectra of all components of cosmic rays including protons, antiprotons, boron, and carbon.
RRI’s Hypothesis on Cosmic Rays Interaction
Cosmic rays, during their course through the Milky Way galaxy, interact with matter producing other cosmic rays, specifically electrons and positrons. RRI proposes that these interactions inside the molecular clouds contribute significantly to the positron excess phenomenon.
Cosmic Rays and Light-Year
Cosmic rays, discovered in 1912, are atom fragments that land on the Earth from outside the solar system at the speed of light. They have been known to cause electronic disruptions in satellites and other machinery.
Defined by the International Astronomical Union, a light-year is a unit of distance measurement used to convey astronomical distances. Equivalent to approximately 9.46 trillion kilometers, a light-year represents the distance covered by light in vacuum over a Julian year.
Source: PIB
