 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
| . |  |
. |
 by Staff Writers Bloomington IN (SPX) May 18, 2018
A study led in part by physicists at the Indiana University Center for the Exploration of Energy and Matter could provide new insight into the composition of the universe immediately after the Big Bang - as well as improve calculations used to predict the life span of stars and describe the rules that govern the subatomic world. The study, published May 11 in the journal Science, reports a highly accurate way to measure the decay rate of neutrons. An author on the study, Chen-Yu Liu, is a professor in the IU Bloomington College of Arts and Sciences' Department of Physics. "This is a significant improvement compared to previous experiments," said Liu, who is a leader on the UNCtau experiment, which uses neutrons from the Los Alamos Neutron Science Center Ultracold Neutron source at Los Alamos National Laboratory in New Mexico. "The data is far more accurate than what we've had before." The rate of the decay of neutrons - subatomic particles with no charge - is significant because it is used to predict the proportion of hydrogen and helium in the universe a few minutes after the Big Bang. The number also affects calculations used to determine how quickly hydrogen atoms burn up inside stars and the rules that control the elementary particles like quarks and gluons. This is because during neutron decay, one "up" quark transforms into a "down" quark, a process that physicists don't yet fully understand. Scientists currently use two methods to isolate neutrons and calculate their decay rates: + The "bottle" method: Counting the number of neutrons that remain over time after being trapped inside a container. + The "beam" method: Measuring the rate of protons that emerge from a neutron beam generated by a nuclear reactor. Some physicists regard the beam method as more accurate because the bottle method risks miscounting neutrons absorbed into the container as disappearing from decay. But the study from Liu and colleagues uses an invisible container made from magnetic fields and gravity to eliminate the risk of interference from physical material. As a result, the experiment can measure a neutron's lifetime with a high level of precision. "A neutron could technically live inside our trap for three weeks, which is much longer than any other previously constructed 'bottle' traps," Liu said. "This long trap lifetime is what makes it possible to achieve a highly accurate measurement." The use of a "magneto-gravitational trap," in which the neutrons' magnetic charge and mass prevent them from escaping their container, also makes it easier to measure the neutrons because the bottle is "lidless," Liu said. Liu's lab joined the UNCtau experiment in 2011 to help re-invigorate the project. The work required five years to design, fabricate, test and install their equipment at the neutron source in Los Alamos, after which the team began to run experiments and collect data. Members of Liu's lab regularly travel to New Mexico to test equipment, run experiments and record the results. "Five years to get an experiment running and producing data is very fast in our field," Liu said. "We spent about six months on site and six months creating hardware each year. It was really a cycle of fast prototyping and improvement. We would never have been able to renovate the technology without the mechanical and technical support available at the IU Center for the Exploration of Energy and Matter."
The big bell test challenges Einstein Washington DC (SPX) May 10, 2018 On November 30th, 2016, more than 100,000 people around the world contributed to a suite of first-of-a-kind quantum physics experiments known as The BIG Bell Test. Using smartphones and other internet-connected devices, participants contributed unpredictable bits, which determined how entangled atoms, photons, and superconducting devices were measured in twelve laboratories around the world. Scientists used the human input to close a stubborn loophole in tests of Einste ... read more
|
|||||||||||||
|
|
| The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |
del.icio.us
Digg
Reddit
Google
