“Zc(3900)”: Scientists find evidence of existence of a new four-quark particle

QuarkParticle physicists performing experiments at the Belle particle detector in Japan and in BESIII detector in China have found evidence of the existence of a four-quark particle named Zc(3900).

About Zc(3900):

Composed of two quarks and two antiquarks.

  • A hadron, a type of subatomic particle made of quarks, believed to be the first tetraquark that has been observed experimentally.
  • A decay product of the previously observed anomalous Y(4260) particle.
  • In turn decays into a charged pion (π±) and a J/ψ meson. This is consistent with the Zc(3900) containing four or more quarks.
What are Quarks?

quark is an elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. Due to a phenomenon known as color confinement, quarks are never directly observed or found in isolation; they can be found only within hadrons, such as baryons (of which protons and neutrons are examples), and mesons.For this reason, much of what is known about quarks has been drawn from observations of the hadrons themselves.

What are the differnt types of Quarks?
  • There are six types of quarks flavorsup, down, strange, charm, bottom, and top.

Up and down quarks have the lowest masses of all quarks. The heavier quarks rapidly change into up and down quarks through a process of particle decay. Because of this, up and down quarks are generally stable and the most common in the universe, whereas strange, charm, top, and bottom quarks can only be produced in high energy collisions (such as those involving cosmic rays and in particle accelerators).

Quarks have various intrinsic properties, including electric charge, color charge, mass, and spin. Quarks are the only elementary particles in the Standard Model of particle physics to experience all four fundamental interactions, also known as fundamental forces (electromagnetism, gravitation, strong interaction, and weak interaction), as well as the only known particles whose electric charges are not integer multiples of the elementary charge.

Quarks have three kinds of charges which are characterized by a quantum number called colour (as three kinds of primary colours exist).

What is Quantum Chromodynamics or QCD?
  • The theory describing the strong interaction of quarks is called Quantum Chromodynamics or QCD.
What is antiquark?
  • For every quark flavor there is a corresponding type of antiparticle, known as anantiquark, that differs from the quark only in that some of its properties have equal magnitude but opposite sign.

Month: Categories: Science & Technology


40% of global population is online: ITU

As per the International Telecommunication Union (ITU), nearly 40% of the global population or 2.7 billion people are already online in 2013 while India still stands far with around 13% Internet penetration with roughly 160 million users.

As per ITU:

  • The percentage of people online in developing and developed world is 31% and 77% respectively.
  • Europe, with 75% Internet penetration, is the region with the highest Internet penetration rate.
  • The US, with 61% penetration, is positioned at the second spot amongst regions.
  • Africa has nearly 16% of its citizens online — only half the penetration rate of Asia-Pacific, where one out of every three (33%) citizens has access to the Internet.
  • More men than women have access to the Internet, but the distinction is not sharp.
  • Globally, 37% of all women are online, compared with 41% of all men.
  • The gender gap is more marked in the developing world, where 16% less women than men use the Internet, compared with only 2% less women than men in the developed world.
  • 41% or nearly 750 million households are connected to the Net by 2013.
  • Nearly half of these households are in the developing world, where household Internet penetration is close to 28%.
  • 78% of households in the developed world are online.
  • In 2013, around 1.1 billion homes globally, of which 90% are in the developing world, are yet to be connected to the Internet.
  • Europe and Africa are the regions with the highest and lowest household Internet penetrations respectively.
  • About 77% households in Europe in contrast to extreme low of 7% in Africa.
  • With an annual growth rate of 27%, Africa’s Internet penetration grew fastest between 2009 and 2013.
  • India is expected to double its Internet users from 160 million to 330 million by 2015.
  • India’s National Telecom Policy ideates for 175 million broadband subscribers by 2017 and 600 million by 2020.

Month: Categories: Science & Technology