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Scientists figure out how to put the brakes on antimatter atoms – CBC.ca

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Antimatter atoms get annihilated whenever they contact matter — which makes up everything.  That makes them hard to study, which has been a problem, scientists say, because studying antimatter is key to understanding how the universe formed.

So the question has been, how can you manipulate antimatter atoms in order to study and measure them properly? 

A team of scientists say they have figured out a way to do that by slowing down antimatter atoms with blasts from a special Canadian-built laser. And they say that could make it possible to create antimatter molecules — larger particles more similar to the matter we encounter in the real world — in the lab.

“This is where it really gets exciting for us,” said Makoto Fujiwara, a research scientist at TRIUMF, Canada’s particle accelerator centre in Vancouver, B.C.  “You can really start doing things that are basically unimaginable previously,”

Fujiwara is a member of the international scientific collaboration known as ALPHA, which has created the Canadian-built laser they say could allow scientists to manipulate, study and measure antimatter like never before. The new technique would allow them to study its properties and behaviour in more detail, compare it to matter, and help answer some of the most fundamental questions in physics about the origin of the universe.

The collaboration, based at the underground lab of CERN, the European Organization for Nuclear Research, published the new research in the journal Nature Wednesday.

The group includes scientists from countries around the world, including Canadian researchers at the TRIUMF, University of British Columbia (UBC), Simon Fraser University, University of Victoria, British Columbia Institute of Technology, University of Calgary and York University in Toronto It receives funding from government agencies including the European Research Council and the National Research Council of Canada, and a few trusts and foundations.

What is antimatter?

According to our understanding of physics, for each particle of matter that exists, there is a corresponding particle of antimatter with the same mass, but opposite charge. For example, the “antiparticle” of an electron — an antielectron, usually called a positron — has a positive charge. 

Antimatter is produced in equal quantities with matter when energy is converted into mass. This happens in particle colliders such as a the Large Hadron Collider at CERN. It’s also believed to have happened during the Big Bang at the beginning of the universe.

But there is no longer a significant amount of antimatter in the universe — a big puzzle for scientists. 

Scientists would like to be able to study antimatter to figure out how it’s different from matter, as that might provide clues about why the universe’s antimatter has apparently disappeared. But there’s a problem — when antimatter and matter encounter each other, they both get annihilated, producing pure energy. (A huge amount — that’s what powers the fictional warp drive in Star Trek).

Because our world is made of matter, working with antimatter is tricky. For a long time, scientists could produce antimatter atoms in the lab, but they’d last just millionths of a second before hitting the matter walls of their container and getting destroyed.

WATCH | Bob McDonald explains why those earlier antimatter experiments were a big deal

Bob McDonald explains why the antihydrogen experiment is a big deal 1:59

Then in 2010, the ALPHA collaboration developed a way to capture and hold antimatter atoms using an extremely powerful magnetic field generated by a superconducting magnet. That magnetic field could keep them away from the sides of their container, which is made of matter, for up to half an hour — giving scientists plenty of time to do measurements on anti-hydrogen that compare it to hydrogen.

Makoto Fujiwara’s ‘crazy dream’

There was a problem though. Much as images you take with your camera are blurry if the object you’re photographing is moving too fast, it was hard to get precise measurements on hydrogen anti-atoms without being able to slow them down. But Fujiwara had an idea of how to do that.

“It’s one of my crazy dreams I had a long time ago — that is, to manipulate and control the motion of antimatter atoms by laser light,” he recalled.

He knew that regular atoms could be slowed down by “laser cooling” (atoms move more slowly at colder temperatures and stop moving at a temperature of 0 Kelvin or 0 K, equivalent to -273.15 C, called absolute zero). Atoms of each element are sensitive to specific colours of light. Hitting them with those specific colours under certain conditions can cause them to absorb light and slow down in the process.

In theory, hydrogen anti-atoms should respond to the same colours as regular hydrogen atoms (something the researchers ended up confirming in 2018.)

WATCH | An ALPHA Canada animation explains how the ALPHA experiment makes and traps hydrogen and takes one kind of measurement

ALPHA Canada animation explains its breakthrough experiment 3:25

So as soon as ALPHA succeeded in trapping antimatter atoms of hydrogen, Fujiwara proposed trying laser cooling on them.

His colleagues laughed, initially, he recalled, “because everybody knew that a laser would be so hard to build for this.”

The colour they needed, represented in physics by its wavelength (for example, red has a wavelength of around 700 nanometres and blue has a wavelength of around 450 nanometres) had to be very precise. It needed a wavelength of exactly 121.6 nanometres . A laser of that colour had never been built before. The laser would also have to fit in a very confined space in a very complex experimental setup with lots of components.

Then, one day, Fujiwara ran into his colleague Takamasa Momose, a UBC chemistry professor, in the cafeteria at TRIUMF in Vancouver. He mentioned the problem, and Momose said he could make the laser.

The two worked together, and after nearly 10 years, they succeeded.

What you can do with ultra-slow antimatter atoms

Antihydrogen atoms are created and trapped at very cold temperatures, about 0.5 Kelvin or K (-272.65 C). But even at that temperature, they’re moving at about 300 kilometres per hour. With laser cooling, the researcher managed to get them down to 0.01 K (-273.14) and a speed of 36 kilometres per hour.

“Almost you can catch up by running,” said Fujiwara (that is, if you’re Usain Bolt, who averaged 37.58 kilometres per hour in his record-breaking 100-metre sprint).

Makoto Fujiwara stands in front of ALPHA experiment apparatus at the European Organization for Nuclear Research (CERN) in Switzerland. The international collaboration equipped the apparatus with the special laser to slow down and cool antimatter atoms of hydrogen. (Maximilien Brice )

The team was able to measure the colours that represent the “fingerprint” of the cooled antihydrogen atoms. And those slow speeds, the measurement was four times sharper than the blurry measurements they had taken at faster speeds and higher temperatures.

Momose said that when the atoms move more slowly, it also allows them to bunch closer together — and perhaps even connect to form bigger particles of antimatter, which he said is his next goal.

“So far we have only antihydrogen atoms,” he said. “But I think it’s cool to make a molecule with antimatter.”

Fujiwara also wants to measure the force of gravity on the antimatter atoms to see if it’s the same as the force of gravity on matter. The force of gravity is very weak on something with as tiny a mass as an atom, and its signal typically gets drowned out by signals from other atomic movements. But because atoms stop moving at absolute zero, those other motions can be greatly reduced with extreme cooling.

Why it’s a ‘nice step forward’

Randolph Pohl is a professor of experimental atomic physics at the University of Mainz in Germany who was not involved in the study, but has worked with antimatter in the past. He has been following ALPHA’s work, and said its latest results are “a nice step forward” toward precise measurements of antihydrogen’s “fingerprint.”

But he thinks the new technique will have an even bigger impact on measurements of gravitational acceleration on antimatter atoms:  “The big question is: will antimatter fall down to earth — will it be attracted to matter? Or could it be repelled by matter or fall upwards?”

He added that so far, no one expects a difference between matter and antimatter in its behaviour, but that theory still needs to be tested.

“Because there have been some occasions in the past where people measured something where nobody expected to see a discrepancy, and then suddenly a discrepancy showed up,” he said. “And that changed our view of the world.”

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Breathtaking NASA Image Shows a Magical ‘Sea of Dunes’ on Mars

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On Thursday, NASA released a stunning photo of a sea of dunes on Mars.

It also shows wind-sculpted lines surrounding Mars’ frosty northern polar cap.

The section captured in the shot represents an area that is 31 kilometers (19 miles) wide, NASA said. The sea of dunes, however, actually covers an area as large as Texas.

The photo is a false color image, meaning that the colors are representative of temperatures. Blue represents cooler climes, and the shades of yellow mark out “sun-warmed dunes,” the US space agency wrote.

Sea of dark dunes surrounds Mars’ northern polar cap.(NASA/JPL-Caltech/ASU)

The photo is made of a combination of images captured by the Thermal Emission Imaging System instrument on the Mars Odyssey orbiter, NASA wrote.

Captured during the period from December 2002 to November 2004, the breathtaking images have been released to mark the 20th anniversary of Odyssey.

The Mars Odyssey orbiter is a robotic spacecraft circling Mars that uses a thermal imager to detect evidence of water and ice on the planet.

It was launched in 2001, making it the longest-working Mars spacecraft in history.

Source:- ScienceAlert

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Humans actually hunted large animals and ate mostly meat for 2 millions years: study – CTV News

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TORONTO —
Despite a widespread belief that humans owe their evolution to the dietary flexibility in eating both meat and vegetables, researchers in Israel suggest that early humans were actually apex predators who hunted large animals for two million years before they sought vegetables to supplement their diet.

In a study recently published in the American Journal of Physical Anthropology, academics from Tel Aviv University in Israel and the University of Minho in Portugal examined modern biology to determine if stone-age humans were specialized carnivores or generalist omnivores.

“So far, attempts to reconstruct the diet of Stone-Age humans were mostly based on comparisons to 20th century hunter-gatherer societies,” one of the study’s authors, Miki Ben-Dor, a researcher at Tel Aviv University, said in a press release.

“This comparison is futile, however, because two million years ago hunter-gatherer societies could hunt and consume elephants and other large animals – while today’s hunter gatherers do not have access to such bounty.”

Instead, the researchers looked at approximately 400 previous scientific studies on human anatomy and physiology as well as archeological evidence from the Pleistocene period, or “Ice Age” period, which began about 2.6 million years ago, and lasted until 11,700 years ago.

“We decided to use other methods to reconstruct the diet of Stone-Age humans: to examine the memory preserved in our own bodies, our metabolism, genetics and physical build,” Ben-Dor said.

“Human behaviour changes rapidly, but evolution is slow. The body remembers.”

They discovered 25 lines of evidence from the studied papers on human biology that seem to show that earlier Homo sapiens were apex predators at the top of the food chain.

For example, the academics explained that humans have a high acidity in their stomachs when compared to omnivores or even other predators, which is important for consuming animal products.

“Strong acidity provides protection from harmful bacteria found in meat, and prehistoric humans, hunting large animals whose meat sufficed for days or even weeks, often consumed old meat containing large quantities of bacteria, and thus needed to maintain a high level of acidity,” Ben-Dor said.

Another piece of evidence, according to the study, is the structure of human fat cells.

“In the bodies of omnivores, fat is stored in a relatively small number of large fat cells, while in predators, including humans, it’s the other way around: we have a much larger number of smaller fat cells,” Ben-Dor said.

HUNTING EXPERTS

In addition to the evidence they collected by studying human biology, the researchers said archeological evidence from the Pleistocene period supports their theory.

In one example, the study’s authors examined stable isotopes in the bones of prehistoric humans as well as their hunting practices and concluded these early humans specialized in hunting large and medium-sized animals with high fat content.

“Comparing humans to large social predators of today, all of whom hunt large animals and obtain more than 70% of their energy from animal sources, reinforced the conclusion that humans specialized in hunting large animals and were in fact hypercarnivores,” the academics noted.

Ben-Dor said Stone-Age humans’ expertise in hunting large animals played a major role in the extinction of certain large animals, such as mammoths, mastodons, and giant sloths.

“Most probably, like in current-day predators, hunting itself was a focal human activity throughout most of human evolution. Other archeological evidence – like the fact that specialized tools for obtaining and processing vegetable foods only appeared in the later stages of human evolution – also supports the centrality of large animals in the human diet, throughout most of human history,” he said.

This is not to say, however, that humans during this period didn’t eat any plants. Ben-Dor said they also consumed plants, but they weren’t a major component of their diet until the end of the era when the decline of animal food sources led humans to increase their vegetable intake.

Eventually, the researchers said humans had no choice but to domesticate both plants and animals and become farmers.

Ran Barkai, one of the study’s authors and a professor at Tel Aviv University, said their findings have modern-day implications.

“For many people today, the Paleolithic diet is a critical issue, not only with regard to the past, but also concerning the present and future. It is hard to convince a devout vegetarian that his/her ancestors were not vegetarians, and people tend to confuse personal beliefs with scientific reality,” he said. 

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Marimaca Copper: First Drill Hole Intersects Broad Zone of Sulphide Copper Mineralization at Marimaca – Junior Mining Network

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VANCOUVER, British Columbia, April 07, 2021 (GLOBE NEWSWIRE) — Marimaca Copper Corp. (“Marimaca Copper” or the “Company”) (TSX: MARI) is pleased to announce the assay results of the first drill hole of a five-hole program targeting extensions of sulphide mineralization below the Company’s flagship Marimaca Oxide Deposit (“MOD”). Drilling encountered a broad zone of chalcopyrite and minor chalcocite, indicating potential for economic sulphide mineralization.

Highlights

  • Drill hole MAR-125 intersected 116m (expected approximate true width) at an average grade of 0.51% CuT from 162m, including two higher grade zones of:
    • 20m with an average grade of 0.77% CuT from 162m; and
    • 42m with an average grade of 0.92% CuT from 236m.
  • Intersection represents a significantly broader zone of mineralization than anticipated from earlier, nearby, sulphide drilling intersections
  • First drill hole of an initial five-hole campaign to test for extensions of mineralization at depth
    • First hole designed to extend mineralization closer to sulphide zones identified in historical drilling
    • Remaining four holes designed to test the limits of mineralization with step outs of approximately 300m at depth and between 400m and 700m along strike to the north and south of the first hole
  • Sulphide drilling to be completed shortly, with assay results on remaining holes expected by the end of April 2021
  • In response to escalating COVID situation in Chile, the Company has initiated a break in drilling which is not expected to impact the original target of testing all identified targets by the end of 1H 2021.

Sergio Rivera, VP Exploration of Marimaca Copper, commented:

“The results of the first hole of this initial campaign are extremely pleasing, exceeding both the widths and grades we had projected for this zone based on earlier drilling completed nearby. The broad intercept of chalcopyrite mineralization shows good continuity downhole, with potentially economic grades, especially at the bottom of the intercept.

“The drilling has also provided additional geological information, which we are using to refine our understanding of the controls of mineralization and to inform future drillhole locations, targeting mineralized extensions at depth and along strike.

“The next four holes are significant step outs from the known mineralized zones outside of the Mineral Resource Estimate area and are designed to test the limits of the mineralized body, both at depth and along strike. The second hole will be collared approximately 350m to the east of MAR-125, targeting mineralization up to 300m below the current deepest mineralization. The third, fourth and fifth holes will be located between 400m and 700m to the north and south of MAR-125, aiming to test for extensions along strike.

“This first hole has provided encouragement that there is potential for economically interesting sulphide mineralization at Marimaca, while the next four drill holes are designed to better delineate the tonnage potential of this.”

Discussion of Campaign Objectives and Results

The current five-hole drilling campaign at the Marimaca Copper Project is designed to test for extensions to mineralization below the MOD. Based on the structural controls of the mineralization, the results of previous geophysical campaigns and earlier drilling, which extended beyond the current Mineral Resource Estimate (“MRE”) area, the Company believes there is the potential for extensions of the mineralized body at depth across the full strike length of the MOD. All drill holes will be drilled at an azimuth of 270o and at -60o, roughly perpendicular to the north-south striking, easterly dipping mineralizing structures. Intercepts should, therefore, be relatively close to the true width of the mineralization.

The first drill hole (MAR-125) encountered a broad zone of dominantly chalcopyrite mineralization with some pyrite and minor chalcocite over a down hole width (expected to be equivalent to approximate true width) of 116m with an average grade of 0.51% CuT. This includes two zones of higher-grade mineralization including 20m with an average grade of 0.77% CuT and 42m with an average grade of 0.92% CuT at the end of the mineralized intercept. The hole was collared to test mineralization approximately 100m to the east of the earlier hole ATR-82, which intersected 44m of sulphide copper mineralization with an average grade of 1.05% CuT, and 200m and 300m east of holes ATR-93 and ATR-94 respectively, which both intersected mineralization with true widths of around 40m with average grades above 1.0% CuT. MAR-125 has demonstrated an extension to this higher-grade mineralization and provides further areas to target for follow up drilling.

MAR-125 is located in the center of the current MRE area, proximal to a zone of relatively high-grade sulphide mineralization intercepted in several drill holes over widths of between 30m and 50m. The remaining four drill holes have been located to test the limits of the mineralization by stepping out significantly at depth and along strike beyond the current MRE area. The collar of the second hole, MAS-03, is located approximately 100m to the south and 350m to the east of MAR-125 and is aimed to intersect mineralization approximately 300m below MAR-125. MAS-02 and MAS-04, located approximately 400m and 700m, respectively, south of MAR-125, and are planned as significant step outs along strike, targeting the conductivity high noted in the IP survey completed across the MOD

Figure 2

Sampling and Assay Protocol

True widths cannot be determined with the information available at this time. Marimaca Copper RC holes were sampled on a 2-metre continuous basis, with dry samples riffle split on site and one quarter sent to the Andes Analytical Assay preparation laboratory in Calama and the pulps then sent to the same company laboratory in Santiago for assaying. A second quarter was stored on site for reference. Samples were prepared using the following standard protocol: drying; crushing to better than 85% passing -10#; homogenizing; splitting; pulverizing a 500-700g subsample to 95% passing -150#; and a 125g split of this sent for assaying. All samples were assayed for CuT (total copper), CuS (acid soluble copper) by AAS. A full QA/QC program, involving insertion of appropriate blanks, standards and duplicates was employed with acceptable results. Pulps and sample rejects are stored by Marimaca Copper for future reference.

Qualified Person

The technical information in this news release, including the information that relates to geology, drilling and mineralization was prepared under the supervision of, or has been reviewed by Sergio Rivera, Vice President of Exploration, Marimaca Copper Corp, a geologist with more than 36 years of experience and a member of the Colegio de Geólogos de Chile and of the Institute of Mining Engineers of Chile, and who is the Qualified Person for the purposes of NI 43-101 responsible for the design and execution of the drilling program.

Mr. Rivera confirms that he has visited the Marimaca Project on numerous occasions, is responsible for the information contained in this news release and consents to its publication.

Contact Information
For further information please visit www.marimaca.com or contact:

Tavistock
+44 (0) 207 920 3150
Jos Simson/Emily Moss 
This email address is being protected from spambots. You need JavaScript enabled to view it. 

Forward Looking Statements

This news release includes certain “forward-looking statements” under applicable Canadian securities legislation. These statements relate to future events or the Company’s future performance, business prospects or opportunities. Forward-looking statements include, but are not limited to, the impact of a rebranding of the Company, the future development and exploration potential of the Marimaca Project. Actual future results may differ materially. There can be no assurance that such statements will prove to be accurate, and actual results and future events could differ materially from those anticipated in such statements. Forward-looking statements reflect the beliefs, opinions and projections on the date the statements are made and are based upon a number of assumptions and estimates that, while considered reasonable by Marimaca Copper, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. Many factors, both known and unknown, could cause actual results, performance or achievements to be materially different from the results, performance or achievements that are or may be expressed or implied by such forward-looking statements and the parties have made assumptions and estimates based on or related to many of these factors. Such factors include, without limitation: risks related to share price and market conditions, the inherent risks involved in the mining, exploration and development of mineral properties, the uncertainties involved in interpreting drilling results and other geological data, fluctuating metal prices, the possibility of project delays or cost overruns or unanticipated excessive operating costs and expenses, uncertainties related to the necessity of financing, the availability of and costs of financing needed in the future as well as those factors disclosed in the Company’s documents filed from time to time with the securities regulators in the Provinces of British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, New Brunswick, Nova Scotia, Prince Edward Island and Newfoundland and Labrador. Accordingly, readers should not place undue reliance on forward-looking statements. Marimaca Copper undertakes no obligation to update publicly or otherwise revise any forward-looking statements contained herein whether as a result of new information or future events or otherwise, except as may be required by law.


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