{"id":4585,"date":"2020-03-31T09:19:14","date_gmt":"2020-03-31T08:19:14","guid":{"rendered":"https:\/\/www.innovationnewsnetwork.com\/?p=4585"},"modified":"2020-03-31T09:19:51","modified_gmt":"2020-03-31T08:19:51","slug":"the-particle-interactions-that-take-place-in-the-core-of-neutron-stars","status":"publish","type":"post","link":"https:\/\/www.innovationnewsnetwork.com\/the-particle-interactions-that-take-place-in-the-core-of-neutron-stars\/4585\/","title":{"rendered":"The particle interactions that take place in the core of neutron stars"},"content":{"rendered":"
Using new results from precision particle detectors at the Relativistic Heavy Ion Collider<\/a> (RHIC) scientists have made groundbreaking discoveries, giving nuclear physicists<\/a> a new way to search for violations of fundamental symmetries in the universe.<\/p>\n The new measurements taken by the research group exposed the binding energy which holds together the components of the simplest \u2018strange-matter\u2019 nucleus, known as a \u2018hypertriton\u2019.<\/p>\n For the second measurement, scientists searched for a difference between the mass of the hypertriton and its antimatter counterpart, the antihypertriton. This discover would prove \u201cCPT\u201d violation, a simultaneous violation of three fundamental symmetries in nature pertaining to the reversal of charge, mirror symmetry, and time.<\/p>\n \u201cPhysicists have seen parity violation, and violation of CP together but never CPT,\u201d said Brookhaven physicist Zhangbu Xu, co-spokesperson of RHIC\u2019s STAR experiment, where the hypertriton research was conducted. According to Xu, no one has looked for CPT violation in the hypertriton and antihypertriton, \u201cbecause no one else could yet.\u201d<\/p>\n Scientists have previously conducted CPT tests of the heaviest nucleus. This was performed by the ALICE collaboration at Europe\u2019s Large Hadron Collider (LHC), where they measured the mass differences between ordinary helium-3 and antihelium-3. Published in 2015, the results showed no significant difference.<\/p>\n Detector components added to STAR tracked different kinds of particles, simplifying the search. These components, called the \u2018Heavy-Flavor Tracker\u2019, are located very close to the STAR detector\u2019s centre. These inner components allow scientists to match up tracks created by decay products of each hypertriton and antihypertriton with their point of origin just outside the collision zone.<\/p>\n \u201cWhat we look for are the \u2018daughter\u2019 particles\u2014the decay products that strike detector components at the outer edges of STAR,\u201d said Berkeley Lab physicist Xin Dong.<\/p>\n Locating pairs or triplets of daughter particles that originate from a single point just outside the primary collision zone allows scientists to pick these signals out of other particles streaming from each RHIC collision.<\/p>\n \u201cThen we calculate the momentum of each daughter particle from one decay (based on how much they bend in STAR\u2019s magnetic field), and from that we can reconstruct their masses and the mass of the parent hypertriton or antihypertriton particle before it decayed,\u201d explained Declan Keane of Kent State University (KSU).<\/p>\n \u201cKeane\u2019s team, including Irakli Chakeberia, has specialized in tracking these particles through the detectors to \u2018connect the dots,\u2019\u201d Xu said. \u201cThey also provided much needed visualisation of the events.\u201d<\/p>\n The STAR physicists derived the binding energy by subtracting their value for the hypertriton mass from the combined known masses of a deuteron (a bound state of a proton and a neutron) and one lambda.<\/p>\n \u201cThe hypertriton weighs less than the sum of its parts because some of that mass is converted into the energy that is binding the three nucleons together\u2026This binding energy is really a measure of the strength of these interactions, so our new measurement could have important implications for understanding the \u2018equation of state\u2019 of neutron stars,\u201d said Fudan University STAR collaborator Jinhui Chen, whose PhD student.<\/p>\n \u201cThere\u2019s great interest in understanding how these interactions\u2014a form of the strong force\u2014are different between ordinary nucleons and strange nucleons containing up, down, and strange quarks,\u201d Chen continued. \u201cBecause these hypernuclei contain a single lambda, this is one of the best ways to make comparisons with theoretical predictions. It reduces the problem to its simplest form.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":" Scientists have made a revolutionary breakthrough surrounding the particle interactions that take place in the core of a neutron star. Using new results from precision particle detectors at the Relativistic Heavy Ion Collider (RHIC) scientists have made groundbreaking discoveries, giving nuclear physicists a new way to search for violations of fundamental symmetries in the universe. […]<\/p>\n","protected":false},"author":4,"featured_media":4586,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[771],"tags":[801,814],"acf":[],"yoast_head":"\nThe search for daughter particles<\/h3>\n