22-Mar-2019: Physicists observe Matter-Antimatter Asymmetry in Charm Particle decays
Physicists from the Large Hadron Collider beauty (LHCb) Collaboration at CERN have observed, for the first time, the matter-antimatter asymmetry known as charge-parity (CP) violation in the decays of a D0 meson, a subatomic particle made up of a charm quark and an up antiquark.
The term CP refers to the transformation that swaps a particle with the mirror image of its antiparticle. The weak interactions of the Standard Model of particle physics are known to induce a difference in the behavior of some particles and of their CP counterparts, an asymmetry known as CP violation. This asymmetry is one of the key ingredients required to explain why today’s Universe is only composed of matter particles, with essentially no residual presence of antimatter.
The phenomenon was first observed in 1964 in the decays of particles called neutral K mesons, which contain a strange quark, and the two physicists who made the discovery, James Cronin and Val Fitch, were awarded the Nobel Prize in physics in 1980. Such a discovery came as a great surprise at the time, as it was firmly believed by the community of particle physicists that the CP symmetry could not be violated.
In the early 1970s, Makoto Kobayashi and Toshihide Maskawa realized that CP violation could be included naturally in the Standard Model. Their fundamental idea was confirmed eventually three decades later by the discovery of CP violation in the decays of neutral B mesons, which contain a bottom quark, by the BaBar and Belle collaborations, leading to the award of the 2008 Nobel Prize in physics to Kobayashi and Maskawa.
There have been many attempts to measure matter-antimatter asymmetry, but, until now, no one has succeeded. It’ a milestone in antimatter research.
To observe the CP asymmetry in the D0 meson, the physicists used the full dataset delivered by the Large Hadron Collider to the LHCb experiment between 2011 and 2018 to look for decays of the D0 meson and its antiparticle, the anti-D0, into either kaons or pions.
We don’t see antimatter in our world, so we have to artificially produce it. The data from these collisions enables us to map the decay and transformation of unstable particles into more stable byproducts.
The result has a statistical significance of 5.3 standard deviations, exceeding the threshold of 5 standard deviations used by particle physicists to claim a discovery.
Ever since the discovery of the D meson more than 40 years ago, particle physicists have suspected that CP violation also occurs in this system, but it was only now, using essentially the full data sample collected by the experiment, that the LHCb Collaboration has finally been able to observe the effect.”
21-Feb-2019: BEL Launches Atmospheric Water Generator safe Drinking Water, Straight From the Air
Navaratna Defence PSU Bharat Electronics Ltd (BEL) has unveiled its new product, the Atmospheric Water Generator (AWG), an innovative solution to meet the ever-increasing need for drinking water worldwide, at Aero India 2019.
Chief of the Army Staff General Bipin Rawat, inaugurated the AWG in the presence of, Chairman and Managing Director BEL Shri MV Gowtama, Directors and other senior officers of BEL.
BEL's Atmospheric Water Generator can be used to generate water straight from the humidity present in the atmosphere. The day is not far when drinking water becomes the most precious commodity on the planet. Groundwater, currently the main source of drinking water, is being depleted at alarming and unsustainable rates even as the search for alternate water sources continues.
BEL's Atmospheric Water Generator employs a novel technology to extract water from the humidity present in the atmosphere and purify it. It uses heat exchange for condensing the atmospheric moisture to produce pure, safe and clean potable water. The AWG comes with a Mineralisation Unit, which is used to add minerals which are required to make the water potable. The AWG is configurable in static and mobile (vehicular) versions and is available in 30 litres/day, 100 litres/day, 500 litres/day and 1,000 litres/day capacities.
The Atmospheric Water Generator can be used to provide drinking water in community centres and public places like health care centres, schools, colleges, offices, railway stations, bus stands, airports, sea ports, off-shore oil rigs, military establishments, remote field areas and remote establishments and residential complexes.
The Atmospheric Water Generator is being manufactured by BEL in collaboration with CSIR-IICT and MAITHRI, a start-up company based in Hyderabad. It is on display at the BEL stall at Hall-E at Aero India 2019. BEL has, as part of the Government of India's Start-up India Initiative, extending its support to start-up Companies.
9-Jan-2019: Erratic motion of north magnetic pole
Something strange is going on at the top of the world. Earth’s north magnetic pole has been skittering away from Canada and towards Siberia, driven by liquid iron sloshing within the planet’s core. The magnetic pole is moving so quickly that it has forced the world’s geomagnetism experts into a rare move.
On 15 January, they are set to update the World Magnetic Model, which describes the planet’s magnetic field and underlies all modern navigation, from the systems that steer ships at sea to Google Maps on smartphones.
The most recent version of the model came out in 2015 and was supposed to last until 2020 — but the magnetic field is changing so rapidly that researchers have to fix the model now. The error is increasing all the time.
The problem lies partly with the moving pole and partly with other shifts deep within the planet. Liquid churning in Earth’s core generates most of the magnetic field, which varies over time as the deep flows change. In 2016, for instance, part of the magnetic field temporarily accelerated deep under northern South America and the eastern Pacific Ocean. Satellites such as the European Space Agency’s Swarm mission tracked the shift.
The pole wanders in unpredictable ways that have fascinated explorers and scientists since James Clark Ross first measured it in 1831 in the Canadian Arctic. In the mid-1990s it picked up speed, from around 15 kilometres per year to around 55 kilometres per year. By 2001, it had entered the Arctic Ocean — where, in 2007, a team including Chulliat landed an aeroplane on the sea ice in an attempt to locate the pole.
In 2018, the pole crossed the International Date Line into the Eastern Hemisphere. It is currently making a beeline for Siberia.
The geometry of Earth’s magnetic field magnifies the model’s errors in places where the field is changing quickly, such as the North Pole. The fact that the pole is going fast makes this region more prone to large errors.
Scientists are working to understand why the magnetic field is changing so dramatically. Geomagnetic pulses, like the one that happened in 2016, might be traced back to ‘hydromagnetic’ waves arising from deep in the core. And the fast motion of the north magnetic pole could be linked to a high-speed jet of liquid iron beneath Canada. The jet seems to be smearing out and weakening the magnetic field beneath Canada. And that means that Canada is essentially losing a magnetic tug-of-war with Siberia.