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first_imgThe protocols are being done in accordance with all federal, state, medical and university guidelines to begin voluntary workouts.Regardless of home state, all athletes will be required to self-quarantine upon arriving on campus for a maximum of 14 days. Quarantine time may vary based on additional guidance from the state and the phase of reopening in Massachusetts.All athletes will be tested for COVID-19 on or about Day 8 of quarantine. Protocols are also in place for the quarantine and treatment of positive COVID-19 cases should they occur.___Two Rutgers football players have tested positive for the new coronavirus. ___Croatian tennis player Borna Coric says he has tested positive for the coronavirus after taking part in an exhibition event.The 33rd-ranked Coric posted the news on Twitter.He says “I want to inform you that I am positive for Covid-19. Please everyone who has been in contact with me for the last few days gets tested!”He says he is feeling well and has no symptoms. Share This StoryFacebookTwitteremailPrintLinkedinRedditThe Latest on the effects of the coronavirus outbreak on sports around the world:___Iowa’s athletic department says nine athletes, coaches or staff have tested positive for COVID-19 in the last week. Coric was among about 1,000 people who were tested for the virus after Grigor Dimitrov announced that he tested positive. That led to the cancellation of an exhibition event in Croatia where top-ranked Novak Djokovic was scheduled to play in the final.Coric played a match against Dimitrov in Zadar on Saturday in the second leg of the exhibition series.___More AP sports: https://apnews.com/apf-sports and https://twitter.com/AP_Sports Incoming freshmen players also were allowed on campus on Monday and they were tested and put in a separate dormitory. They will not be integrated with the rest of the team until they pass a second COVID-19 test.The workouts are voluntary and Schiano said some players have elected to skip them.___The ATP men’s tennis tour says it is continuing to “plan and adjust” its precautions and protocols related to the coronavirus pandemic with an eye to its planned Aug. 14 resumption of competition.The tour issued a statement Monday following word that two top-35 players tested positive for COVID-19 after participating in unsanctioned exhibition matches organized by No. 1 Novak Djokovic in Serbia and Croatia. June 22, 2020 The Blue Jackets were informed Monday that Columbus will not be one of the NHL’s hub cities. Columbus was one of 10 finalists, including seven in the U.S.Las Vegas is now considered the U.S. favorite to host NHL playoff games, unless two Canadian cities are selected. Canada’s federal government last week said it would allow the league to quarantine internally, making Toronto, Vancouver and Edmonton realistic possibilities — if not the front-runners.The NHL has said it will select two hub cities — one for the Eastern Conference playoffs and one for the Western Conference. The Stanley Cup Final or “final four” would likely be in one of the two cities.___Wisconsin officials say that two Badgers’ athletes have tested positive for COVID-19 and are self-isolating. Those positive results came from the 117 athletes who participated in the school’s initial campus screening. The Wisconsin athletic department’s infection response team is monitoring the recovery of the athletes but didn’t specify which teams the two play for. Wisconsin plans to release the aggregate number of positive tests at regular intervals during the initial phase of athletes’ return to campus.___Boston College says its football players began returning to the school Monday as part of its COVID-19 operational plan to bring all its student-athletes back to campus.The school says its new protocols include limiting personnel at facilities, mandating face coverings be worn in common areas, as well as daily temperature checks for staff and athletes. Increased cleaning measures will also be in effect at all facilities. The club says the players are feeling fine and remain in isolation.Four of the players have displayed symptoms of COVID-19 while one has shown no symptoms at all.The club says the five players did not attend the match against Proleter on Saturday when the Serbian league champions completed their season.About 20,000 fans attended a Serbian Cup semifinal match against Partizan Belgrade this month as the country lifted most of its COVID-19 restrictions.The match against Proleter was also attend by about 20,000 fans. Both gatherings have drawn criticism from the public as Serbia records dozens of new coronavirus cases each day.center_img Coach Greg Schiano discussed the test results Monday during a conference call. It was his first media availability since the team was allowed to return to campus last week for voluntary workouts.Schiano said players and coaches were tested before the team returned on June 15, either with mail-in tests or after being tested locally. One of the positive tests came from those samples and the player was not allowed to return to campus and is being isolated at home.The second positive test came from a sample taken when the players reported. That player was isolated and three players who had contact with him were placed in quarantine.The university has a protocol for allowing players who test positive to eventually return, which includes a non-positive test, Schiano said.Schiano said players and coaches underwent a third screening on Monday. Associated Press That accounts for nearly one-quarter of the 40 tests conducted in that time frame. Since the beginning of the return-to-campus protocol May 29, there have been 12 positives among 386 tests.The athletic department said contact tracing has begun. Individuals who test positive are being isolated, and a quarantine is in place for individuals who might have been exposed to someone with COVID-19.“While we have experienced an increase in positive tests, almost all are related to individuals who had been in quarantine due to our contact tracing and developed symptoms,” stated Dr. Andrew Peterson, head team physician. “Our overall process, including testing and daily health screening, is working as expected.”___Players of Brazilian soccer giant Corinthians visited the club on Monday to pick up personal protection equipment against COVID-19 after tests showed 21 out of its 27 players had contracted the disease. The São Paulo-based club said Sunday that 13 players are fully recovered, but eight will not be allowed to start training on July 1 because of the disease. Corinthians tested 190 people, including players, staffers and their families. The club did not name the players who tested positive. Brazil is Latin America’s hardest hit country by the new coronavirus, with more than 50,000 deaths and 1 million confirmed cases.___The National Hockey League has begun winnowing its possible locations to resume the season amid the COVID-19 pandemic. The Latest: There were no social distancing measures observed at the Adria Tour exhibitions.Three-time Grand Slam semifinalist Grigor Dimitrov, who is currently No. 19, and his opponent in Croatia on Saturday, No. 33 Borna Coric, both said they have COVID-19.The ATP said it “continues to urge strict adherence to responsible social distancing and health and safety guidelines to contain the spread of the virus.”Exhibition events have been staged in various places around the world while the ATP and WTA tours have been suspended since March because of the pandemic. The tours announced last week they plan to return in August.___ Louisville football’s season opener against North Carolina State has been moved up a day to Wednesday, Sept. 2 to avoid conflicting with the rescheduled Kentucky Derby weekend at neighboring Churchill Downs.The Kentucky Oaks and Derby were postponed from May 1-2 to Sept. 4-5 because of the coronavirus pandemic. The preceding and highly attended Thursday race card known as “Thurby” was set for the same day as the Cardinals’ Atlantic Coast Conference matchup against the Wolfpack, but the schools announced Monday that they had agreed to the switch to avert logistical conflicts with parking and traffic.“We appreciate the NCAA, ACC and N.C. State honoring our request for a date change for the opening game,” Louisville athletic director Vince Tyra said in a news release. “We are trying to be thoughtful about the shared city resources needed to host a football game and Thurby at the same time.”___Serbian soccer club Red Star Belgrade says five players have tested positive for the coronavirus.last_img read more

Weird new form of nuclear matter might lie just beyond experimenters grasp

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first_img Within a neutron star—the remains of an exploded, middle-weight star—pressures climb a billion billion times higher than in the sun’s core. For decades, some theoretical physicists have speculated that under those conditions, a bizarre type of matter might emerge: a soup of the subatomic particles called quarks. Now, a new analysis indicates the recipe for that soup, called cold quark matter, needs revision. If correct, it suggests that particle accelerators on Earth might be able to produce stable bits of the quark matter. It also would put the kibosh on hypothetical particles called strangelets, which fearmongers once claimed could destroy the world.“It’s a speculative argument, but there is nothing obviously wrong with it,” says Robert Pisarski, a nuclear theorist at Brookhaven National Laboratory in Upton, New York, who was not involved in the work.Atomic nuclei consist of protons and neutrons, which themselves consist of trios of up and down quarks—two of the particles’ six “flavors”—bound tightly by the strong nuclear force. Since the 1970s, some theorists have predicted that under extreme pressures like those in the hearts of neutron stars, quarks might break free of their strong-force chains to create a soup of cold quark matter. They also predicted that the soup’s ingredients would differ from those of protons and neutrons. Their calculations suggested that to minimize its energy, quark matter should include a third flavor of quarks known as strange quarks. Sign up for our daily newsletter Get more great content like this delivered right to you! Country By Adrian ChoMay. 15, 2018 , 2:30 PM Even though strange quarks emerge only fleetingly, usually in collisions at particle accelerators, calculations suggested that such strange quark matter might have a lower energy than ordinary nuclear matter has. That means that specks of strange quark matter, or strangelets, could be stable and that, in principle, ordinary nuclei could change into them. That transformation would require simultaneous conversions of up and down quarks to strange quarks—something unlikely to happen spontaneously in the age of the universe. But strangelets generated in cosmic rays or lingering from violent astrophysical events might survive indefinitely. Scientists have searched for them in many ways, so far unsuccessfully.Now, Bob Holdom, a nuclear theorist at the University of Toronto in Canada, and his colleagues say they have banished strange quark matter with better estimates of how, through quantum effects, quarks change the energy of the vacuum of space itself, a key component of quark matter’s total energy. “Our model allows us to see how the vacuum energy depends on the flavor of the quark,” Holdom says. Mixing in strange quarks incurs a bigger energy penalty than previously thought, so high that cold quark matter should consist of just up and down quarks, the researchers report in a paper in press at Physical Review Letters.Atomic nuclei clearly don’t readily convert into up-down quark matter either. The team calculates that for masses below about 300 times that of the proton, ordinary nuclei are stable because effects akin to surface tension increase quark matter’s energy. However, if experimenters striving to make new superheavy elements could push up in mass just a bit beyond the heaviest nucleus spotted yet—oganesson, with an atomic mass of 294—then they might make stable “nuggets” of up-down quark matter, the theorists predict.Is this the end for strange quark matter? Probably not, Pisarski says. The theory of quarks is so mathematically intractable that, like everybody else, Holdom had to resort to approximate models, he says. Laura Paulucci, an astrophysicist at the Federal University of ABC in São Paulo, Brazil, adds that the analysis also doesn’t quite rule out strange quark matter in neutron stars, where the density should be significantly higher than the theorists assume. “I’m not sure the theory they’re using is adequate” for the conditions in neutron stars, she says.Still, the study may be good news for scientists hunting stable quark matter, says Evan Finch, an experimenter at Southern Connecticut State University in New Haven who has searched for strangelets by running moon dust through a mass spectrometer and looking for particles with odd charge-to-mass ratios. “There’s a suggestion that maybe we’ve been looking in the wrong place” for quark matter, he says. “I’m a bit skeptical, but it’s fun.”The new picture of cold quark matter could also dispel a far-fetched threat to the world. Opponents of the Large Hadron Collider in Switzerland had argued that the atom smasher might produce negatively charged strangelets that would gobble up positively charged atomic nuclei in a runaway process. Physicists had countered that if such a catastrophe were possible, strangelets from space would have long since consumed the planet. Up-down quark matter would definitively rule out the doomsday scenario: It should be positively charged and repel atomic nuclei.Still, a nugget of the stuff could be useful, Holdom says. Bombard it with neutrons and it would convert them to quark matter while generating energy, he predicts. 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A new study suggests the soup may lack strange quarks. Email Click to view the privacy policy. Required fields are indicated by an asterisk (*) Image: (X-ray) NASA/CXC/University of Amsterdam/N. Rea et al.; (Optical) DSS last_img read more