Российская наука и мир (дайджест) - Август 2014 г.
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Российская наука и мир
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январь февраль март апрель май июнь июль август сентябрь октябрь ноябрь декабрь
    ScienceInsider / 1 August 2014
    Geopolitics disrupt scientific exchange with Russia
    • By Eli Kintisch
    Напряженность в отношениях России и США начинает сказываться на научном сотрудничестве: у ряда американских ученых возникли проблемы с участием в российских конференциях, запланированные совместные проекты откладываются на неопределенный срок. По мнению самих ученых, эти ограничения понятны, но "хотелось бы, чтобы политика не влияла на науку".

Tensions with Russia over the unrest in Ukraine are inflicting collateral damage on science. ScienceInsider has learned that several U.S. scientists have pulled out of upcoming conferences in Russia.
Some cancellations stem from policy guidance that the U.S. government issued to agencies this spring to clamp down on travel by government scientists to Russia. Based on that guidance, NASA and the Department of Energy (DOE) announced in April that they would block most government travel to Russia; other agencies are reviewing and in some cases not allowing such travel.
"There has been some diplomatic pushing and shoving behind the scenes," says Dale Meade, a physicist emeritus with the U.S. DOE's Princeton Plasma Physics Laboratory in New Jersey.
Some DOE scientists who had planned to attend the International Atomic Energy Agency's conference on fusion in St. Petersburg in October have requested permission to travel there but have not received any guidance. The approval process for travel to Russia is shrouded in secrecy, says Rita Guenther, a program officer at the National Academies in Washington, D.C., who is tracking the issue. "There is no one policy that all agencies share. Each meeting is looked at independently, and each instance of scientific cooperation is looked at independently."
The conflicting signals from DOE are frustrating researchers. "This is the biggest fusion meeting of the year. Especially now, with ITER at such a critical phase, one would want to participate in the meeting," Meade says. The irony, he says, is that the $17.5 billion ITER collaboration grew out of efforts in the 1980s to improve scientific ties between the Soviet Union and the West. "One of the original goals of the project was to use scientific research to ease tensions during the Cold War. This is now being replayed in reverse," Meade says.
Plans for meetings in other fields have also been disrupted. Physicist Geoffrey Bodwin of Argonne National Laboratory in Lemont, Illinois, was invited to give a plenary talk at a meeting on subatomic particles next month in St. Petersburg, one of several U.S. government scientists listed on the conference website as participants. But Bodwin, who declined to comment, has not been able to get approval for his travel. DOE did not respond to questions about Bodwin's case, noting only in a statement to ScienceInsider that "[g]iven the current standing of the United States' relationship with Russia, the Department of Energy closely evaluates all cooperative interactions with the Russian Federation on a case by case basis."
Another meeting that will lose a prominent speaker is an international confab on extremophiles in St. Petersburg next month. Russian-born plenary speaker Eugene Koonin, a biologist at the National Center for Biotechnology Information in Bethesda, Maryland, recently canceled his attendance, he says, for "various reasons … some of them personal." He declined to specify the reasons.
Other meetings have fared better. Vladimir Poroikov, a computational biologist at the Institute of Biomedical Chemistry in Moscow, was concerned that tensions would disrupt a meeting he is chairing later this summer in St. Petersburg on chemical-biological interactions. A sponsor from Ukraine, not surprisingly, canceled its involvement, forcing Poroikov to find other funding. But he says that turnout is looking good. Russia has placed no restrictions on foreign scientists, Poroikov says, and the 300 attendees include several from the United States including the plenary speaker, Marc Nicklaus of the National Cancer Institute.
Most Russian-U.S. research projects appear to be weathering the geopolitical storm. Scientists at the U.S. National Oceanic and Atmospheric Administration received approval from the National Security Council for a joint research cruise last month to sample the Bering Strait under a long-term monitoring project called RUSALCA. One possible casualty is nascent projects getting started under the U.S.-Russia Bilateral Presidential Commission in health, environmental, and information sciences. A State Department official told ScienceInsider in a statement that "in response to Russia's illegal intervention in Ukraine" some of that research has been "postponed." But the official declined to say which projects. He added:
"In general, the United States considers scientific work to be vital to U.S. national interests and we are not seeking to isolate Russia's society. We are reviewing all bilateral engagement on a case by case basis, but believe it is in our interest to work together with Russia on scientific research."
Restrictions on U.S.-Russian collaborations may be "understandable" given the circumstances, says Michael Lubell, director of public affairs at the American Physical Society in Washington, D.C., but "you'd like to have scientific exchanges not tainted by the politics."

© 2014 American Association for the Advancement of Science. All Rights Reserved.
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    Wired / 04.08.14
    A Peek Into Life in "Silicon Forest," Russia's Hot New Startup Scene
    • By Pete Brook
    Об новосибирском Академгородке и Академпарке.

The town of Akademgorodok, nestled among birch and conifers 3,400 kilometers east of Moscow, is becoming a hub for 21st century Russian innovation and entrepreneurship. You've heard of Silicon Valley. This is Silicon Forest.
Visual journalist Grant Slater recently traveled to the remote Siberian city to document the tech boom and create a broad portrait of the people driving, and caught up in, the changes.
"Initially, I was just curious to see what the inside of a Russian tech incubator looked like," he says. "As I spent more time there, I became interested in the character of this town as a whole."
Akademgorodok has a storied past when it comes to innovation but only recently became the center of Russia's tech world. The town, founded in 1957 by the Soviet Academy of Sciences, was the result of a plan by Nikita Khrushchev to huddle the Soviet Union's sharpest minds. At its peak, Akademgorodok (which translates as "Academy Town") was home to a university, 35 research institutes, a medical academy, and 65,000 scientists and their families.
Immediately following the collapse of the Soviet Union, however, Akademgorodok experienced a massive brain drain as engineers fled to the West. Novosibirsk University remained an important institution, but citizens of nearby Novosibirsk, Russia's third largest city, transformed Akademgorodok into a bedroom community.
Its rebirth began last summer when President Vladimir Putin and the Kremlin ordered a federal takeover of the Siberian branch of the Russian Academy of Science with the intent of once again making Akademgorodok a technological centerpiece, this time focused on start-ups instead of nuclear science. The push toward a very 21st-century culture was something of a culture shock, and long-time professors, engineers and physicists took to the streets in protested.
"I wanted to explore how the legacy of Soviet state-driven science clashed or coalesced with the ideals and values of startup culture," Slater says of his choice to shoot young techies and scientists in the established institutes. "I'm interested in the way technology or - the idea the future - manifests itself. One of the interesting aspects of that is the way different cultures view innovation."
Nowadays, the main institution in Akademgorodok is a 13-story startup incubator called Akadempark. It is home to Playtox, which makes games for mobile web browsers; Winkcam, an app that lets you take photos with your phone even when it's locked using the accelerometer; and Genetic Test, a company that uses genetic traits in biometric access and analysis. Start-ups win a place at Akadempark by successfully pitching their ideas during winter and summer academies.
"When I was there, one of the recent winners was [a start-up developing] an improved version of the infamous Russian dash-cam with extra sensors to help prevent accidents, a bit like a dumbed-down version of the Google self-driving car," says Slater.
If you need excess gases cleaned from anesthesia machines, or a personal-trainer webcam consultation for distance training, you'll be no doubt calling on products developed at Akadempark. Start-ups are given a one-year runway to turn a profit at their company. It's early days for all involved.
"Everything is just now getting started," says Slater, who thinks that the glass floors and skybridge of the incubator as compared with the Soviet functionalism of the old institutes depicts the conscious effort to present Russian technology and science as that of the future, not the past. Akadempark and Akademgorodok generally are headed in the right direction but it's a long way from Silicon Valley.
"Russian officials view these projects as a way to diversify its economy away from oil and gas," says Slater, "but it is far from becoming a 21st-century economy that pumps out tech startups."

WIRED.com © 2014 Condé Nast. All rights reserved.

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    Eureka! Science News / Monday, August 11, 2014
    Astrophysicists detect destruction of 3 stars by black holes
    Исследователи из МФТИ и Института космических исследований РАН выявили на основании данных, полученных рентгеновскими орбитальными обсерваториями ROSAT и XMM-Newton, три возможных случая приливного разрушения звезд сверхмассивными черными дырами. Разрушение звезды сверхмассивной черной дырой происходит, когда звезда проходит слишком близко от нее, что случается раз в 10000 лет и сопровождается мощным рентгеновским излучением.
    Статья "Stellar tidal disruption candidates found by cross-correlating the ROSAT Bright Source Catalogue and XMM-Newton observations" будет опубликована в журнале Monthly Notices of the Royal Astronomical Society.

Researchers from MIPT and the Space Research Institute of the Russian Academy of Sciences have reported registering three possible occasions of the tidal destruction of stars by supermassive black holes at the centers of galaxies. Details are given in an article by Ildar Khabibullin and Sergei Sazonov, accepted for publication by the Monthly Notices of the Royal Astronomical Society. The astrophysicists used data obtained by X-ray orbiting observatories ROSAT and XMM-Newton. The former was put into orbit in 1990 and served until 1999, when XMM-Newton took over. The two satellites gathered enough information to detect very rare events, the destruction of stars by supermassive black holes.
A star in a galaxy passes by a black hole closely enough to be destroyed once every 10,000 years. It is possible to detect the death of a star in a fairly distant galaxy as the destruction of a star generates a bright X-ray flare; it is only necessary to distinguish such a flare from other types of X-ray radiation. Because flares occur in a variety of astrophysical processes, the task of finding stars destroyed by black holes is quite complicated.
The researchers developed a number of methods to distinguish the destruction of a star by a black hole from other occurrences. The easiest way to filter out extraneous signals is to eliminate from consideration flares in our galaxy; there is only one supermassive black hole at the center of the Milky Way, so there clearly could not have been stars that have become victims of gravity on the periphery of our galaxy. The researchers also excluded sources of radiation that were too large (in angular measurements) and additionally analyzed the range of objects along with the dependence of brightness on time.
Since a supermassive black hole takes just a few years to fully absorb the captured matter of a destroyed star (typically, this makes up about a quarter of its original mass), observations repeated a decade later should detect significant dimming of an X-ray source. The researchers obtained sky survey data in the 1990s and in the 2000s, so they were able to detect objects whose brightness reduced by at least tenfold.
The data led to the identification of three X-ray sources labeled1RXS J114727.1 + 494302, 1RXS J130547.2 + 641252 and 1RXS J235424.5-102053. [1RXS means that the object was first noticed during the first survey of the sky by the ROSAT telescope, and the two six-digit numbers after the letter J are angular coordinates.]
There is another object that may be a star that has been ripped apart, but the available data does not allow for distinguishing it from the active nucleus of a distant galaxy. New data suggests that the destruction of stars near black holes occur once every 30,000 years within the same galaxy, which agrees quite well with estimates derived from observations in the visible and ultraviolet spectral range.
The uncertainty of these estimates is quite significant since they are based on a very small number of occurrences - the full sample contains no more than two dozen "credible" X-ray sources registered by various methods in different spectral bands. Progress in this area is expected to be made with the launch of the space observatory Spectrum-X-Gamma in 2016, which will be equipped with two X-ray telescopes in the soft X-ray wavelength (the Russian-German unit eROSITA) and in the hard wavelength (Russia's ART-XC). They will be used to carry out eight new legs of X-ray sky surveys within four years. The sensitivity of each shot will be several times greater than that of ROSAT.
Researchers estimate that several hundred such occurrences will be registered annually with the help of Spectrum-X-Gamma. This will not only allow them to more accurately measure the average frequency of such occurrences in the universe, but also to examine in greater detail the interaction of supermassive black holes with surrounding objects.

© 2014 (e) Science News.

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    FierceDrugDelivery / August 20, 2014
    Russian scientists close in on drug-delivering nanorobots
    • By Varun Saxena
    Ученые из Института общей физики РАН и МФТИ нашли способ "научить" наночастицы выполнять логические операции при помощи внешнего слоя из биомолекул. В дальнейшем это может помочь в создании нанороботов, способных доставить лекарство к больной клетке, самостоятельно отличив ее от здоровой.
    Статья "Biocomputing based on particle disassembly" опубликована в журнале Nature Nanotechnology.

Researchers at the Institute of General Physics at the Russian Academy of Sciences and the Moscow Institute of Physics and Technology said their advancement in biocomputing using nanoparticles is a step toward creating nanorobots. These are capable of delivering drugs in the form of molecular payloads, which the scientists compared to the creation of transistors - which advanced to eventually power computers.
Most studies in this area have focused on the performance of intracellular "logical operations" that form the basis of computing, but the teams said they have developed a method of enabling extracellular nanoparticles and microparticles to follow the boolean commands "and," "yes," "no" and "or."
Researchers accomplished this feat by designing the nanoparticles in such a way that the coating behaves differently when exposed to various signals, or inputs, at the particle/biomolecule interface. As a result, the team was able to create nanoparticles that targeted cells when two different criteria were met (presumably following the boolean operation "and"). Scientists were able to home in specifically on cancer cells.
By "input-induced disassembly" of the nanoparticles, logic-gating can be achieved. That means inputs (like the signal that the nanoparticle encounters via the particle/biomolecule interface) associated with a logical command can be mapped to outputs, or outcomes, on a decision tree.
The researchers say their study, appearing in the journal Nature Nanotechnology, is the first publication in a major scientific magazine in years about an experiment conducted by an exclusively Russian team.

© 2014 FierceMarkets, a division of Questex Media Group LLC. All rights reserved.

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    Uncover California / Wed, 08/20/2014
    Family of Pterosaurs was Toothless, Still Dominated Earth's Early Skies
    • By Andrea Cordell
    Российский палеонтолог Александр Аверьянов (Зоологический институт РАН) представил подробное исследование таксономии, территориального распространения и среды обитания аждархидов - семейства последних на Земле летающих ящеров, куда входил и крупнейший представитель отряда птерозавров кетцалькоатль.
    Статья "Review of taxonomy, geographic distribution, and paleoenvironments of Azhdarchidae (Pterosauria)" опубликована в журнале ZooKeys.

According to a new study by Russian paleontologists, a species of huge flying lizards once dominated earth's skies despite being toothless. Size of Azhdarchid pterosaurs was similar to a small aircraft. The name of Azhdarchid pterosaurs is inspired from the Persian word Azdarha meaning dragon.
The flying creatures had the wingspan of between 10 and 12 meters wide. It was an unusual species of pterosaurs as it did not have teeth in contrast to earlier pterosaurs that had a fine set of chompers. But it was the population of the Azhdarchids without teeth that thrived, despite lack of dental prowess. The giant dragons survived until about 60 million years ago.
Some fundamental changes in Cretaceous ecosystems must have led to the shift in dominance from toothed to toothless pterodactyloids, said the author of the study, Dr. Alexander Averianov, from the Zoological Institute of the Russian Academy of Sciences.
Researchers consider pterosaurs as the first vertebrates. The species was pushed to extinction by the Chicxulub asteroid impact. The flying pterosaurs did not have the feathers found in modern birds and had wings of skin that were occasionally covered by fine hair for warmth.
However, there was something in similar with birds like pterosaurs has hollow bones to save weight and maintain proper flight.
"Azhdarchidae currently represent a real nightmare for paleontologists: most taxa are known from few fragmentary bones, which often do not overlap between named taxa, the few articulated skeletons are poorly preserved, and some of the best available material has remained undescribed for forty years", said Averianov.
Scientists do not know much about the eating habits of the species, but study of their fossils has indicated that they enjoyed fish and other marine life. It appeared that they were used to gather near large lakes and rivers and marine environment to satiate their hunger.

© 2014 Uncover California Online Media.

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    Phys.org / Aug 25, 2014
    Cannibalism may contribute to the successful invasion by harlequin ladybirds of new habitats
    Французские, бельгийские, российские (Институт леса имени В.Н.Сукачёва СО РАН) и британские ученые пришли к выводу, что каннибализм азиатских божьих коровок (Harmonia axyridis), в последнее время активно вытесняющих местные виды насекомых, может обеспечить им преимущество при освоении новых мест обитания. Каннибализм является довольно распространенным поведением среди насекомых, однако в случае азиатских божьих коровок он представляет собой реальное эволюционное преимущество.
    Статья "Cannibalism in invasive, native and biocontrol populations of the harlequin ladybird" опубликована в журнале BMC Evolutionary Biology.

INRA research scientists, working in collaboration with European and Russian scientists, have studied the cannibalistic behaviour of native and invasive populations of the Harmonia axyridis ladybird. Their findings suggest that this behaviour may procure them a real survival advantage during the colonisation of new habitats.
Harmonia axyridis is better known as the Asiatic or harlequin ladybird. Present today on all continents, it takes its name from its region of origin, identified as being in Asian countries: Japan, China, Korea and Eastern Russia. Sadly, this ladybird species is now renowned for its massive invasive episodes that are widely reported in the media. Initially, from the 1910s, this ladybird was used in North America, Europe and then South America to control aphid populations in productive greenhouses. At the end of the 20th century, Harmonia axyridis suddenly became invasive in a large part of the American continent, and a few years later in Western Europe and parts of South America and Africa. In these affected regions it overwhelms native species, thus disturbing natural ecosystems.
To try and understand this abrupt invasive behaviour, French, Belgian, Russian and British researchers studied the evolution of cannibalism in Harmonia axyridis during its development. In fact, cannibalism is a widespread behaviour in insects, linked to the genetic profile of individuals. The degree of recourse to cannibalism varies within species and is dependent on the density of a population and the resources available to it.
The scientists compared three samples of ladybirds maintained in similar experimental environments but presenting different genetic traits: a group of invasive individuals collected in France and the UK, a group made up of native individuals from Russia and Japan, and a third group comprising ladybirds reared in the laboratory and used for biological control. In all three groups, they observed that the level of cannibalism - which consists in eating the eggs - was much higher among larvae than among adults, and increased significantly in line with the rise in population density.
The scientists therefore suggest that larvae - unlike adults - are unable to leave the leaves on which the eggs have hatched and are therefore incapable of searching elsewhere for sources of food. Cannibalism therefore appears to be a spontaneous response to a situation of nutritional depletion to which the larvae are not adapted, unlike adults that are more able to fast or disperse and find food.
A second important finding was that the level of cannibalism was markedly higher among the invasive larvae than in the other two groups. These results agree with the hypothesis of them procuring an advantage through cannibalism following their introduction into a new environment.
The scientists also tried to determine whether the level of cannibalism had evolved during the geographical spread of these invasive ladybirds in Europe. To achieve this, they compared samples collected from recently invaded regions in France with samples collected in Belgium, where Harmonia axyridis was reported as early as 2001. The results showed that the level of cannibalism was the same in these two samples.
These results suggest that this survival tactic has only developed to the benefit of larvae and during the initial phases of invasion, as cannibalism rates were similarly low among adults in all the populations studied. Cannibalism may therefore represent a real evolutionary benefit that is specifically selected in invasive individuals of Harmonia axyridis during their colonisation of new habitats.
More information: Ashraf Tayeh, Arnaud Estoup, Eric Lombaert, Thomas Guillemaud, Natalia Kirichenko, Lori Lawson-Handley, Patrick De Clercq and Benoît Facon, "Cannibalism in invasive, native and biocontrol populations of the harlequin ladybird," BMC Evolutionary Biology 2014 DOI: 10.1186/1471-2148-14-15.

© Phys.org™ 2003-2013.
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    ActuaLitté / Le jeudi 28 août 2014
    Les bibliothèques de Russie disponibles en 2015 sur applications iOS et Android : les solutions pour consulter le patrimoine russe
    Фонды ведущих библиотек России, входящих в программу Национальной электронной библиотеки (НЭБ), в 2015 году будут доступны на смартфонах и планшетах. Можно будет искать необходимые книги в каталоге, а также читать их и сохранять тексты. В первую очередь планируется предоставить доступ к классической литературе, диссертациям и историческим документам.

Le fonds des plus importantes bibliothèques de Russie sera prochainement mis à disposition des smartphones du pays, dans un vaste mouvement patrimonial. Le responsable des établissements de prêt au ministère de la Culture, Evguenya Guseva, explique qu'une application iOS et Android sera proposée début 2015. Son objectif est de remplacer à terme la carte de bibliothèque.
Les deux applications, qui ne seront qu'une, permettront d'effectuer des recherches à l'intérieur d'un catalogue de 6 millions de documents, mais également de télécharger des images ou d'explorer du texte en ligne. Tous les possesseurs de mobiles auront, au creux de la main, les œuvres de littérature classiques, un catalogue de thèses et de nombreuses sources historiques.
Bien entendu, seules les ressources du domaine public seront disponibles.
Pour Evguenya Guseva, cette sorte de carte de bibliothèque numérique pourra faciliter la vie de l'ensemble des utilisateurs. Les applications seront gratuites, mais, évidemment, l'intégralité des ressources n'est pas encore en consultation. Les collections de la bibliothèque nationale de Russie représentent 162 To d'informations, difficiles à rendre publiques sur une application.
Parmi les établissements qui participent, on retrouve la Bibliothèque d'État de Russie, la Bibliothèque nationale de Russie, la bibliothèque présidentielle, la Bibliothèque Boris Eltsine ainsi que la bibliothèque d'État publique scientifique et technique.
En parallèle, des ressources sous droit seront également accessibles, à l'avenir, et pour le responsable, tout l'enjeu passera par le cryptage des données, pour les protéger contre la copie non autorisée. Tatouage numérique ou chiffrement seront les deux pistes à prendre en compte, explique l'appel d'offres, émis par le ministère.
Les utilisateurs n'auront pas à s'enregistrer pour profiter des contenus libres de droits, mais devront passer par une identification pour les autres. Avec la redistribution de droits pour les auteurs, bien évidemment. Cependant, les modalités de rémunérations n'ont pas été évoquées. Ce pan n'étant pas encore opérationnel, il entrera dans une réflexion prochaine, avec pour perspective la lutte contre le piratage, véritable fléau en Russie.
Au ministère de la Culture, on assure que ce développement s'inscrit dans les nouvelles pratiques de la bibliothéconomie, avec " un accès libre, en ligne, aux principaux fonds d'ouvrages occidentaux ". Le coût de ce développement est de 4,365 millions de roubles, soit plus de 90.000 euros.

© 2007-2014 - Actualitte.com. Tous droits réservés.
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    Science 2.0. / August 29th 2014
    Radioactive Cobalt Detected In A Supernova Explosion
    Российские астрофизики из Института космических исследований РАН, Института астрономии РАН и МФТИ сообщили о первом в истории орбитальной астрономии наблюдении гамма-излучения от сверхновой звезды типа Iа. Гамма-кванты от термоядерного взрыва, случившегося 11 миллионов лет назад в галактике М82, зарегистрировала международная астрофизическая лаборатория гамма-лучей ИНТЕГРАЛ - проект Европейского космического агентства совместно с Роскосмосом и NASA.
    Статья "Cobalt-56 γ-ray emission lines from the type Ia supernova 2014J" опубликована в журнале Nature.

Astrophysicists have detected the formation of radioactive cobalt during a supernova explosion, lending credence to a corresponding theory of supernova explosions.
The article's main author, Yevgeny Churazov (Space Research Institute of the Russian Academy of Sciences), and co-authors, including Sergei Sazonov of the Space Research Institute and MIPT, reported the results of their analysis of data collected with the INTEGRAL gamma-ray orbital telescope, which they used to detect the radioactive isotope cobalt-56(56Co).
Isotope 56Co has a half-life of just 77 days, and does not exist in normal conditions. However, during a giant thermonuclear explosion of a supernova, this short-lived radioactive isotope is produced in large quantities. Radiating cobalt was registered at the supernova SN2014J, located 11 million light-years from Earth.
Astrophysicists never obtained similar spectra before. The reason was the rarity of explosions at such a distance - 11 million light-years is a large value on the galactic scale (the diameter of a galaxy is about 100,000 light-years, the distance between stars is a few light-years), but on an intergalactic scale it is a relatively short distance. There are several hundreds of galaxies within a radius of ten million light-years; supernovae produce explosions like this (type Ia explosions) once every few centuries in a galaxy. For example, a type Ia supernova last exploded in the Milky Way in 1606.
SN2014J was registered on January 21, 2014 by astronomer Steve Fossey and a group of students from University College London in the galaxy M82. Fossey reported the discovery, and several observatories, including INTEGRAL, started observations immediately. Russian researchers spent a million seconds of their quota for the use of the INTEGRAL telescope to study the supernova. In addition to the spectra, they obtained data on how the brightness of radiation changes over time.
According to a theory that was developed earlier, during an explosion of the Ia type, the remnants of a star barely radiate in the gamma range the first dozens of days. The star's shell is opaque in this region of the spectrum; a supernova begins to produce gamma radiation only after the outer layer becomes sufficiently rarefied. By that time, radioactive nickel-56 with a half-life of 10 days, synthesized during the explosion, transforms into radioactive cobalt-56, the lines of which were detected by the researchers.
The essence of spectral analysis remains unchanged whatever the nature of radiation. For light, X-rays and even radio waves, scientists first plot a graph of a spectrum, or the relationship of intensity and frequency (or, equivalently, wavelength: wavelength is inversely proportional to frequency).
The graph's shape indicates the nature of the source of radiation and through what environment the radiation has passed. Spectral lines, or sharp peaks on such graphs, correspond to certain events like the emission or absorption of quanta by atoms during transition from one energy level to another.
During formation, cobalt-56 had a surplus of energy, exhausted in the form of gamma rays with energies of 847 keV and 1237keV; other isotopes produced radiation with quanta of different energies and thus could not be confused with cobalt-56.
The data collected by the INTEGRAL telescope also allowed the researchers to assess how much radioactive cobalt was emitted during the explosion - the equivalent of about 60% of the Sun's mass.
Over time, cobalt-56 turns into the most common isotope of iron, 56Fe.56Fe is the most common isotope because it can be obtained from nickel emitted during supernovae explosions (nickel turns into cobalt, and cobalt turns into iron).
Thus, the new results back up simulations of supernovae explosions and also confirm that our planet consists of matter that has gone through thermonuclear explosions of an astronomical scale.

© 2014 ION Publications LLC.
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Документ изменен: Wed Feb 27 14:56:52 2019. Размер: 42,686 bytes.
Посещение N 1609 с 26.09.2014