Scientists Excited by Potential New Force of Nature
2021-04-19
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1Have you ever heard of a muon?
2A muon is a very small particle similar to an electron.
3Electrons and protons are parts of the atoms that make up all matter.
4Muons were discovered during an experiment in 1936.
5Until now, most physicists have only been able to study muons for an extremely short period of time: two microseconds.
6There are one million microseconds in one second.
7But scientists are using new technology to study these particles for a longer period of time than in the past.
8And with that extra time, they think they have made an exciting discovery.
9By watching the muons, they found that these particles do not behave as predicted.
10Scientists have developed a group of expectations, or rules, in the years that they have studied particles that are smaller than an atom.
11That group of rules is called the Standard Model.
12Scientists agreed on the Standard Model about 50 years ago.
13The Standard Model lets physicists make assumptions about the way extremely small particles move.
14Over time, experiments have proved that the assumptions of the Standard Model are correct.
15However, results of two different recent tests in Europe and America have scientists thinking again about their ideas.
16The scientists who work at the research center called Fermilab, near Chicago, Illinois have done 8.2 billion tests with muons.
17They send them around a 14-meter magnetic track.
18The special track keeps the muons from disappearing for longer than usual, so they can be studied.
19The tests showed scientists that the muons were behaving differently than the Standard Model predicted.
20In tests going on at a research center near Geneva, Switzerland, scientists crash particles known as "beauty quarks" into each other.
21The Standard Model says these crashes should produce an equal number of electrons and muons each time.
22However, researchers looked at data over several years and found 15 percent more electrons than muons resulted from the collisions.
23They had expected nearly an equal number of both particles.
24The physicists are excited to be able to question the Standard Model.
25They think it means an important discovery might be coming in the near future.
26However, they say the information from the experiments still requires a lot of study.
27It will take another one or two years before they can make a firm statement.
28David Kaplan is a physicist at Johns Hopkins University.
29He said if the experiments turn out to be correct, they could upset the world of particle physics.
30What the early data show is that there is an unknown particle or force acting on the muons.
31Aida El-Khadra who works at Fermilab said it would be the first big discovery in this part of physics in about 10 years.
32Chris Polly is one of the leaders of the project at Fermilab.
33He said there could be a "sea of background particles" that have not yet been discovered.
34He called them: "monsters we haven't yet imagined."
35Alexey Petrov is a particle physicist at Wayne State University in Michigan.
36He said the news of the discovery is "tantalizing."
37Both groups doing the experiments want people to understand that their findings need to be confirmed with more tests.
38In 2011, physicists thought they found something that made them question the Standard Model.
39They said another particle, known as a neutrino, was traveling faster than the speed of light.
40But after careful reexamination, they found the result came from loose electrical wiring in the experiment.
41Sheldon Stone of Syracuse University is working on the project in Switzerland.
42Because of the problem in 2011, he said the scientists are being extra careful.
43"We're kind of confident," about the results, he said. "But you never know."
44I'm Dan Friedell.
1Have you ever heard of a muon? 2A muon is a very small particle similar to an electron. Electrons and protons are parts of the atoms that make up all matter. 3Muons were discovered during an experiment in 1936. Until now, most physicists have only been able to study muons for an extremely short period of time: two microseconds. There are one million microseconds in one second. 4But scientists are using new technology to study these particles for a longer period of time than in the past. And with that extra time, they think they have made an exciting discovery. By watching the muons, they found that these particles do not behave as predicted. 5Scientists have developed a group of expectations, or rules, in the years that they have studied particles that are smaller than an atom. That group of rules is called the Standard Model. 6Scientists agreed on the Standard Model about 50 years ago. The Standard Model lets physicists make assumptions about the way extremely small particles move. Over time, experiments have proved that the assumptions of the Standard Model are correct. 7However, results of two different recent tests in Europe and America have scientists thinking again about their ideas. 8The scientists who work at the research center called Fermilab, near Chicago, Illinois have done 8.2 billion tests with muons. They send them around a 14-meter magnetic track. The special track keeps the muons from disappearing for longer than usual, so they can be studied. The tests showed scientists that the muons were behaving differently than the Standard Model predicted. 9In tests going on at a research center near Geneva, Switzerland, scientists crash particles known as "beauty quarks" into each other. The Standard Model says these crashes should produce an equal number of electrons and muons each time. However, researchers looked at data over several years and found 15 percent more electrons than muons resulted from the collisions. They had expected nearly an equal number of both particles. 10The physicists are excited to be able to question the Standard Model. They think it means an important discovery might be coming in the near future. 11However, they say the information from the experiments still requires a lot of study. It will take another one or two years before they can make a firm statement. 12David Kaplan is a physicist at Johns Hopkins University. He said if the experiments turn out to be correct, they could upset the world of particle physics. 13What the early data show is that there is an unknown particle or force acting on the muons. Aida El-Khadra who works at Fermilab said it would be the first big discovery in this part of physics in about 10 years. 14Chris Polly is one of the leaders of the project at Fermilab. He said there could be a "sea of background particles" that have not yet been discovered. He called them: "monsters we haven't yet imagined." 15Alexey Petrov is a particle physicist at Wayne State University in Michigan. He said the news of the discovery is "tantalizing." 16Both groups doing the experiments want people to understand that their findings need to be confirmed with more tests. In 2011, physicists thought they found something that made them question the Standard Model. They said another particle, known as a neutrino, was traveling faster than the speed of light. But after careful reexamination, they found the result came from loose electrical wiring in the experiment. 17Sheldon Stone of Syracuse University is working on the project in Switzerland. Because of the problem in 2011, he said the scientists are being extra careful. 18"We're kind of confident," about the results, he said. "But you never know." 19I'm Dan Friedell. 20Seth Borenstein of the Associated Press wrote this story. Dan Friedell adapted it for Learning English. Mario Ritter, Jr. was the editor. 21Are you excited by the news about the muons? Tell us in the Comments Section and visit our Facebook page. 22___________________________________________ 23Words in This Story 24exciting -adj. causing feelings of interest and enthusiasm : causing excite 25assume -v. to think that something is true or probably true without knowing that it is true 26spin -v. to think that something is true or probably true without knowing that it is true 27track -n. a structure that is often circular that lets something go around it in a set path 28monster -n. a strange or horrible imaginary creature 29tantalize -v. to cause (someone) to feel interest or excitement about something that is very attractive, appealing, etc. 30confident -adj. having a feeling or belief that you can do something well or succeed at something : having confidence