Representative ImageReutersThe Maharashtra Anti-Terrorist Squad have said that ISIS-inspired militant youths planned to poison water sources in Mumbai. The plot was revealed during the investigation of the Mumbra temple poisoning case.The Ummat-E-Mohammaddiya group, which is reported to have links with the Islamic State, had planned to poison the temple offering at the Mumbreshwar Mahadev temple’s Shrimadh Bhagwat Katha in Mumbra last year. The offering was to be consumed by 40,000 devotees during the festival in December. New findings by ATS revealed that the terror group was also planning to poison water bodies all over the Mumbai city that would have led to mass deaths, reported DNA.The report said that accused Jaman Nawab Khuteupad, who is also a chemical expert, had prepared the vicious concoction before they were arrested. The 32-year-old worked as a pharmacist at the Brihanmumbai Municipal Corporation (BMC) and was a key member of the militant group.Around 10 members of the group were arrested in January by the ATS before the group carried out the operation. A detailed charge sheet based on an investigation by ATS submitted before the Mumbai High Court in July said that the suspected terrorists were inspired by contentious preacher Zakir Naik.The accused have been identified as Abu Hamza, Fahad Ansari, Talha Potrik, Mohsin Khan alias Abu Marya, Mohammad Takky Khan alias Abu Khalid, Atai Waris Abdul Rashid Shaikh alias Mazhar, Salman Khan alias Abu Ubeda, Mushahed Ul-Islam, Jaman Nawab Khuteupad alias Abu Kital and a minor.Apart from Khuteupad who prepared poison, another member, identified as Talha Potrick, also played a major role as a recruiter for carrying out the operation. The police were alerted after some recruits backed-off and tipped the police about the group’s operation plans.
“Most conventional atomic clocks need a more conventional, non-atomic clock, like a quartz crystal, to keep them ticking,” William Happer tells PhysOrg.com. “We’ve developed a system that would be self-ticking, using a specific laser.” Redefining the limits of measurement accuracy This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. “It’s really a souped-up mode-locked laser,” Happer says. “While our laser has much in common with a mode-locked laser, there are some differences. The atoms in the vapor cell notice if the frequency of the mode-locked laser drifts and they automatically correct the frequency with no need for any external feedback loops.”Happer continues: “An important benefit of push-pull pumping with alternating circular polarization is that none of the atoms are wasted.” “In most atomic clocks,” Jau adds, “many of the atoms are wasted. Only a very few are in the clock state. With this push-pull pumping, all of the atoms are put into a clock state.”Along the way, the two discovered something interesting. “The self-modulation occurs over a limited range of laser injection current. We weren’t surprised that too little current didn’t work. What surprised us was that too much current caused the laser to stop modulating,” Happer says. Jau continues: “This new oscillator, where the polarized atoms, the modulated photons, and the laser gain centers are all coupled together has very rich and interesting physics. ”Happer does point out that these oscillators could not replace the extremely precise, but large atomic clocks that occupy whole rooms. “It’s really to improve the workings of small, portable atomic clocks,” he emphasizes. “It eliminates the need for quartz crystals or photodetectors. Hopefully, with fewer parts, it will be less expensive to manufacture, and more stable.”Jau agrees: “This is a primitive idea, how to make an atomic clock by using pure optical methods without a quartz crystal. But it works better with reduced components and power consumption.”Copyright 2007 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. Citation: Self-ticking oscillator could be next for portable atomic clocks (2007, December 10) retrieved 18 August 2019 from https://phys.org/news/2007-12-self-ticking-oscillator-portable-atomic-clocks.html Happer is a scientist at Princeton University. He, along with his young colleague Yuan-Yu Jau, invented a push-pull laser-atomic oscillator that can be useful in a variety of applications, including questions of fundamental physics, use in portable atomic clocks and coherent optical combs. “We didn’t start out thinking about applications, really,” Happer says. “We’re physicists. We just wanted to see if we could make this type of oscillator work.” The results of Happer and Jau’s work can be found in Physical Review Letters: “Push-Pull Laser-Atomic Oscillator.”Jau explains that even though they didn’t set out to build a better portable atomic clock, he thinks that they have succeeded. “We believe this is the first demonstration of making an oscillator that produces an atomic-clock signal in both electrical and optical forms by purely optical means,” he says. “This is simple. There are fewer components and lower power consumption.”“The new clock needs neither a quartz crystal with its electronics nor a photodetector,” Happer adds.Jau and Happer explain that in conventional atomic clocks, a quartz crystal is used “as a flywheel to keep the clock ticking strongly, with the atoms as a weak controlling element.” They point out that if the quartz crystal fails, the clock will cease working. “These are the types of clocks used in GPS satellites and in cell-phone towers,” Happer says.Jau points out that better precision is becoming increasingly necessary: “Mini atomic clocks can be helpful. There are many systems now working faster and faster, and transmitting large quantities of data, especially in high-speed communications. A laser atomic clock like this would be less complicated than the conventional kind, with comparable precision.”The push-pull laser-atomic oscillator built by the two consists of a semiconductor laser with alkali-metal vapor (in this case Potassium) in the external cavity. A time independent current is used to pump the semiconductor laser. “The laser will automatically modulate its light and its electrical impedance at the clock frequency of the atoms,” Happer says. This in turn eliminates the need for an external modulator, like the quartz crystal, or for a photodetector. Explore further
MORRISTOW — In celebration of Tartan Week, CIE Tours International has announced new offers on top Scottish tours.Taking place from April 3-10, with National Tartan Day scheduled for April 6, Tartan Week encourages millions of North Americans to reconnect with their Scottish roots. And as a leader in premier guided vacations to Britain and Ireland, CIE Tours is joining in on the week-long festivities with substantial discounts on up to seven of its Scotland-based itineraries.There are two ways to save on Scotland this April with CIE:‘Scottish Clans & Castles’ Tour of the Week: Clients save 15%, or $1,000-$1,683, when booking between April 3-9April Promotion: Clients enjoy 10% off select summer departures for the following Scottish tours when booked by April 22: ‘Scottish Dream’ (8 days, from $2,552 per person); ‘Taste of Scotland & Ireland’ (10 days, from $3,225 per person); ‘Best of Britain’ (10 days, from $3,654 per person); and ‘Highlights of Britain’ (15 days, from $5,396 per person)More news: Hotel charges Bollywood star $8.50 for two bananas and the Internet has thoughtsBefore booking, CIE has three fun facts for Scotland-bound travellers:There are more than 150 languages, in addition to English, spoken in Scotland.13% of the country’s population identifies as ginger, the highest proportion in the world.More than 800 islands comprise Scotland, of which only 100 are inhabited.“Scotland has much to offer travellers, whether they choose to immerse themselves in the stunning landscape, delve into the rich culture of the country, explore the deep royal connections or sample the finest Scotch whiskey,” said the company.For more information go to cietours.com. Tags: CIE Tours, Promotions, Scotland Travelweek Group CIE Tours celebrates Tartan Week with up to 15% off Scottish tours Tuesday, April 2, 2019 Posted by << Previous PostNext Post >>