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  • richardmitnick 12:11 pm on June 17, 2020 Permalink | Reply
    Tags: "The Universe's largest particle accelerators are a whole lot bigger", , , , Centaurus A is favourable to scientists for such a study., CNRS, Cosmic gamma-ray emitters, , Gamma-ray emissions from quasars,   

    From CNRS: “The Universe’s largest particle accelerators are a whole lot bigger” 

    CNRS bloc

    From Centre Nationnal de la Recherche Scientifique [The National Center for Scientific Research ]

    17 Jun 2020

    H.E.S.S. Director:
    Prof. Dr. Stefan Wagner
    +49 6221 541 712
    swagner@lsw.uni-heidelberg.de

    H.E.S.S. Deputy Director:
    Prof. Dr. Mathieu de Naurois (CNRS, France)
    +33 1 69 33 55 97 denauroi@in2p3.fr

    DESY, Germany:
    Dr. Andrew Taylor
    +49 33762 7-7195
    andrew.taylor@desy.de

    CNRS Press Officer (France):
    Véronique Etienne
    +33 1 44 96 51 37
    veronique.etienne@cnrs.fr

    DESY Press officer (Germany):
    Dr. Thomas Zoufal Phone:
    +49 40 8998-1666
    presse@desy.de
    Quasar jets are particle accelerators thousands of light-years long.
    1
    Centaurus A, composite image, ESO WFI/APEX and NASA Chandra

    An international collaboration bringing together over 200 scientists from 13 countries has shown that the very high-energy gamma-ray emission from quasars, galaxies with a highly energetic nucleus, is not concentrated in the region close to their central black hole but in fact extends over several thousand light-years along jets of plasma. This discovery shakes up current scenarios for the behaviour of such plasma jets. The work, published in the journal Nature on June 18th, 2020, was carried out as part of the H.E.S.S collaboration, involving in particular the CNRS and CEA in France, and the Max Planck society, DESY and a group of research institutions and universities in Germany.

    H.E.S.S. Čerenkov Telescope Array, located on the Cranz family farm, Göllschau, in Namibia, near the Gamsberg searches for cosmic rays, altitude, 1,800 m (5,900 ft)

    Over the past few years, scientists have observed the Universe using gamma rays, which are very high-energy photons. Gamma rays, which form part of the cosmic rays that constantly bombard the Earth, originate from regions of the Universe where particles are accelerated to huge energies unattainable in human-built accelerators. Gamma rays are emitted by a wide range of cosmic objects, such as quasars, which are active galaxies with a highly energetic nucleus. The intensity of the radiation emitted from these systems can vary over very short timescales of up to one minute. Scientists therefore believed that the source of this radiation was very small and located in the vicinity of a supermassive black hole, which can have a mass several billion times that of the Sun’s. The black hole is thought to gobble up the matter spiralling down into it and eject a small part of it in the form of large jets of plasma, at relativistic speeds, close to the speed of light, thus contributing to the redistribution of matter throughout the Universe.

    Using the H.E.S.S observatory in Namibia, an international astrophysics collaboration observed a radio galaxy (a galaxy that is highly luminous when observed at radio wavelengths) for over 200 hours at unparalleled resolution. As the nearest radio galaxy to Earth, Centaurus A is favourable to scientists for such a study, enabling them to identify the region emitting the very high-energy radiation while studying the trajectory of the plasma jets. They were able to show that the gamma-ray source extends over a distance of several thousand light-years. This extended emission indicates that particle acceleration does not take place solely in the vicinity of the black hole but also along the entire length of the plasma jets. Based on these new results, it is now believed that the particles are reaccelerated by stochastic processes along the jet. The discovery suggests that many radio galaxies with extended jets accelerate electrons to extreme energies and might emit gamma-rays, possibly explaining the origins of a substantial fraction of the diffuse extragalactic gamma background radiation.

    These findings provide important new insights into cosmic gamma-ray emitters, and in particular about the role of radio galaxies as highly efficient relativistic electron accelerators. Due to their large number, it would appear that radio galaxies collectively make a highly significant contribution to the redistribution of energy in the intergalactic medium. The results of this study required extensive observations and optimized analysis techniques with H.E.S.S., the most sensitive gamma-ray observatory to date. Next-generation telescopes (Čerenkov Telescope Array, or CTA) will no doubt make it possible to observe this phenomenon in even greater detail.

    The H.E.S.S. International Observatory, consisting of five telescopes located in Namibia, involves laboratories from thirteen countries (mainly France and Germany, but also Namibia, South Africa, Ireland, Armenia, Poland, Australia, Austria, Sweden, the United Kingdom, the Netherlands and Japan).

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
    Information, communication and knowledge
    Environment, energy and sustainable development
    Nanosciences, nanotechnologies, materials
    Astroparticles: from particles to the Universe

     
  • richardmitnick 2:07 pm on December 1, 2018 Permalink | Reply
    Tags: A new method for weighing super-massive black holes, , , , CNRS, ,   

    From Centre Nationnal de la Recherche Scientifique [The National Center for Scientific Research ]: “A new method for weighing super-massive black holes” 

    CNRS bloc

    From Centre Nationnal de la Recherche Scientifique [The National Center for Scientific Research ]

    29 November 2018

    Scientists have revealed, for the first time outside our Galaxy, the properties of rapidly moving gas clouds in the immediate vicinity of a super-massive black hole, enabling the mass of the black hole to be measured with unprecedented accuracy. The measurement was carried out using the GRAVITY instrument on the Very Large Telescope (VLT, European Southern Observatory) by an international team led by the Max Planck Institute for Extraterrestrial Physics and including researchers from the CNRS, Observatoire de Paris – PSL, Université Grenoble-Alpes and Observatoire de la Côte d’Azur. The findings are published in Nature on 29 November 2018.

    ESO VLTI GRAVITY

    Researchers usually estimate the mass of super-massive black holes located in the heart of galaxies by observing the motion of stars or gas rotating around them: broadly speaking, the faster they rotate, the more massive the black hole is. For distant galaxies, direct measurement of the motion of gas very close to the black hole has until now been impossible, as these regions of gas are too small to be observable. To estimate the mass of the central black hole, astrophysicists therefore measure the time delay between the emission of light from the immediate environment of the black hole and its reverberation from the gas clouds, and use this to infer the size of the gas structure and, hence, the mass of the black hole. This method is known as ‘reverberation mapping’.

    In this new study, astrophysicists used the VLT’s GRAVITY instrument to investigate 3C 273, the first quasar ever identified, located in the centre of a galaxy about 2.5 billion light years away. Using a technique called interferometry, the GRAVITY instrument combines the light collected by the four telescopes of the VLT in Chile. Equivalent to a 130-metre diameter telescope, this combination provides astronomers with hugely increased spatial resolution that would, for example, make it possible to detect a 1 euro coin placed on the Moon.

    Using GRAVITY to observe quasar 3C 273, they were able to detect for the first time the motion of rotating gas clouds in the immediate vicinity of a quasar’s black hole. With a radius of nearly 4 000 billion kilometres, the observed gas structure rotates at speeds of several thousand kilometres per second around an axis corresponding to the jet of matter emitted by the quasar.

    These findings enabled them to ‘weigh’ the super-massive black hole at the centre of 3C 273. The mass estimated using GRAVITY, about 300 million solar masses, is consistent with previous measurements obtained by reverberation mapping, but with 100 times greater accuracy.

    GRAVITY therefore validates the reverberation mapping method for weighing super-massive black holes and also provides a new, independent and extremely accurate method for measuring their mass in thousands of other quasars.

    1
    Optical image of quasar 3C 273, obtained with the Hubble Space Telescope. The quasar is located in the heart of a giant elliptical galaxy in the Virgo constellation, at a distance of about 2.5 billion light years. A jet of matter emitted from the central regions of the galaxy is visible on the left of the image. © NASA/ESA Hubble

    2
    Map of cloud velocity in the gas disc surrounding the super-massive black hole. The red dots correspond to clouds moving away from the observer, the blue ones to clouds moving towards the observer. The distribution of the dots in the figure indicates the rotation of the clouds around a rotation axis that coincides with the direction of the jet emitted by the quasar. © GRAVITY Collaboration

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
    Information, communication and knowledge
    Environment, energy and sustainable development
    Nanosciences, nanotechnologies, materials
    Astroparticles: from particles to the Universe

     
  • richardmitnick 2:59 pm on April 30, 2018 Permalink | Reply
    Tags: , , , , CNRS, , The laws of star formation challenged   

    From Centre National de la Recherche Scientifique (CNRS): “The laws of star formation challenged” 

    CNRS bloc

    Centre National de la Recherche Scientifique [The National Center for Scientific Research ]

    30 April 2018

    An international team led by researchers at CNRS, Université Grenoble Alpes and the French Alternative Energies and Atomic Energy Commission (CEA) has challenged currently held ideas about star formation. The unprecedented resolution of the observations obtained using the Atacama Large Millimetre/Submillimetre Array (ALMA) enabled them to measure the quantity of high-mass star-forming cores in a remote, very active region of our Galaxy, and show that there is a higher proportion of them there than expected.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    Published in Nature Astronomy, the findings could challenge the widespread assumption that the mass distribution of a population of star-forming cores is identical to that of the stars they spawn.

    n space, hidden behind the dusty veils of nebulae, clouds of gas clump together and collapse, forming the structures from which stars are born: star-forming cores. These cluster together, accumulate matter and fragment, eventually giving rise to a cluster of young stars of various masses, whose distribution was described by Edwin Salpeter as an astrophysical law in 1955.

    Astronomers had already noticed that the ratio of massive objects to non-massive objects was the same in clusters of star-forming cores as in clusters of newly-formed stars. This suggested that the mass distribution of stars at birth, known as the IMF1, was simply the result of the mass distribution of the cores from which they formed, known as the CMF2. However, this conclusion resulted from the study of the molecular clouds closest to our Solar System, which are not very dense and therefore not very representative of the diversity of such clouds in the Galaxy. Is the relationship between the CMF and the IMF universal? What do we observe when we look at denser, more distant clouds?

    These were the questions asked by researchers at the Grenoble Institute of Planetology and Astrophysics (CNRS/Université Grenoble Alpes) and the Astrophysics, Instrumentation and Modelling Laboratory, (CNRS/CEA/Université Paris Diderot)3 when they started to observe the active star-formation region W43-MM1, whose structure is far more typical of molecular clouds in our Galaxy than those observed previously. Thanks to the unprecedented sensitivity and spatial resolution of the ALMA antenna array in Chile, the researchers were able to establish a statistically robust core distribution over an unmatched range of masses, from solar-type stars to stars 100 times more massive. To their surprise, the distribution did not obey Salpeter’s 1955 law.

    It turned out that, in the W43-MM1 cloud, there was an overabundance of massive cores, while less massive cores were under-represented. These findings call into question not only the relationship between the CMF and the IMF, but even the supposedly universal nature of the IMF. The mass distribution of young stars may not be the same everywhere in our Galaxy, contrary to what is currently assumed. If this turns out to be the case, the scientific community will be forced to re-examine its calculations about star formation and, eventually, any estimates that depend on the number of massive stars, such as the chemical enrichment of the interstellar medium, the numbers of black holes and supernovae, etc.

    The teams will continue their work with ALMA within a consortium of around forty researchers. Their aim is to study 15 regions similar to W43-MM1 in order to compare their CMFs and ascertain whether the characteristics of this cloud can be generalised.

    2
    The active star-formation region W43-MM1, as observed using the world’s largest millimetre interferometer, ALMA. The high number of star formation sites, known as cores and here identified by ellipses, are evidence of the intense star formation activity in this region. © ESO/ALMA/F. Motte/T. Nony/F. Louvet/Nature Astronomy.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
    Information, communication and knowledge
    Environment, energy and sustainable development
    Nanosciences, nanotechnologies, materials
    Astroparticles: from particles to the Universe

     
  • richardmitnick 8:43 am on October 4, 2017 Permalink | Reply
    Tags: , , , CNRS, , ,   

    From CNRS: “MATISSE to shed light on the formation of Earth and planets” 

    CNRS bloc

    Centre Nationnal de la Recherche Scientifique [The National Center for Scientific Research ]

    25 September 2017
    Contacts:
    Researcher Observatoire Côte d’Azur
    Bruno Lopez
    bruno.lopez@oca.eu

    Press:
    Observatoire Côte d’Azur
    Marc Fulconis
    marc.fulconis@oca.eu

    CNRS Press Office
    Julien Guillaume
    T +33 1 44 96 46 35
    julien.guillaume@cnrs-dir.fr

    The MATISSE instrument is ready to be sent to Chile, where in the next few weeks it will be installed on the Very Large Telescope (VLT), the world’s most powerful astronomical observatory.

    ESO CNRS VLT Matisse Multi-AperTure mid-Infrared SpectroScopic Experiment

    ESO/VLT at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level

    This achievement is the outcome of fifteen years of development, including a final year of testing at the Laboratoire J.-L. Lagrange (Observatoire Côte d’Azur/CNRS/Université de Nice Sophia-Antipolis). The instrument, for which France is responsible under the auspices of the European Southern Observatory (ESO), is international in scope. By observing the protoplanetary disks that surround young stars, the MATISSE project should improve our understanding of the formation of the Earth and of planets in general.

    MATISSE is one of the few projects for which France has responsibility under the auspices of the ESO. In early October 2017, the MATISSE (Multi AperTure mid-Infrared SpectroScopic Experiment) instrument will travel to the Atacama desert in Chile to be installed on the ESO’s Very Large Telescope (VLT), the world’s most powerful astronomical observatory. Eight to ten months’ performance validation observing the sky under real conditions will then be required before the instrument is made available to the international astronomical community.

    With MATISSE, one of the major goals of researchers is to observe protoplanetary disks in order to understand the formation of our own planet and that of planets in general. To achieve this, the instrument will enable astronomers to observe the sky with unprecedented resolution in the mid-infrared region—at wavelengths of 3 to 13 micrometers—and to combine the light from four of the VLT’s eight telescopes at Cerro Paranal, Chile, including the four large eight-meter telescopes. Using the instrument it will be possible to observe the dust and gas surrounding young stars that make up the basic building blocks from which planets form. The environments of stars younger than our own Sun, which have been difficult to observe until now, should shed light on the conditions under which different types of planets form: gas giants like Jupiter, and smaller rocky planets like Earth.

    MATISSE will operate in the same range of wavelengths as the James Webb Space Telescope, which will be launched in 2019 by NASA, and to which it is complementary. NASA researchers are already collaborating with the MATISSE consortium in order to step up joint research.

    NASA/ESA/CSA Webb Telescope annotated

    A number of European organizations were involved in developing the project: the Observatoire de la Côte d’Azur (OCA) and the CNRS in France, the MPIA, MPIfR and ESO in Germany, and NOVA-ASTRON in the Netherlands.

    Status

    Preliminary acceptance Chile: 2019
    First light on telescope: Early 2018
    Now
    Preliminary acceptance Europe: September 2017
    Final Design Review, March 2012
    Optical and Cryogenics Final Design Review, September 2011
    Preliminary Design Review, December 2010

    Baseline Specification
    Requirement
    Optical Throughput 15% (goal 25%) in L and N band
    Wavelength coverage L, M and N band
    Spectral Resolution 20< R <1000 in L band, 20 < R <550 in M band and 20 < R < 250 in N band
    Field of View n/a
    Spatial Sampling n/a
    Interferometric Contrast 0.6 (goal 0.75) in L and N band
    Observing modes High Sensitivity (HighSens) and Simultaneous Photometry (SiPhot)

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
    Information, communication and knowledge
    Environment, energy and sustainable development
    Nanosciences, nanotechnologies, materials
    Astroparticles: from particles to the Universe

     
  • richardmitnick 1:22 pm on September 6, 2017 Permalink | Reply
    Tags: CNRS, , DIBs-diffuse interstellar bands (DIBs),   

    From CNRS: “Does the organic material of comets predate our Solar System?” 

    CNRS bloc

    Centre Nationnal de la Recherche Scientifique [The National Center for Scientific Research]

    4 September 2017
    Contacts:
    CNRS researcher
    Jean-Loup Bertaux
    jean-loup.bertaux@latmos.ipsl.fr

    Paris Observatory researcher
    Rosine Lallement
    rosine.lallement@obspm.fr

    CNRS press officer
    Julien Guillaume l
    (+33) (0)1 44 96 46 35 / 51 51 l
    julien.guillaume@cnrs-dir.fr

    The Rosetta space probe discovered a large amount of organic material in the nucleus of comet “Chury.” In an article published by MNRAS on August 31, 2017, two French researchers advance the theory that this matter has its origin in interstellar space and predates the birth of the Solar System.

    ESA/Rosetta spacecraft

    1
    67P Churyumov-Gerasimenko, a.k.a. Chury

    The ESA’s Rosetta mission, which ended in September 2016, found that organic matter made up 40% (by mass) of the nucleus of comet 67P Churyumov-Gerasimenko, a.k.a. Chury. Organic compounds, combining carbon, hydrogen, nitrogen, and oxygen, are building blocks of life on Earth. Yet, according to Jean-Loup Bertaux and Rosine Lallement—from Laboratoire Atmosphères, Milieux, Observations Spatiales (CNRS / UPMC / Université de Versailles Saint-Quentin-en-Yvelines) and the Galaxies, Étoiles, Physique et Instrumentation department of the Paris Observatory (Observatoire de Paris / CNRS / Université Paris Diderot), respectively—these organic molecules were produced in interstellar space, well before the formation of the solar system. Bertaux and Lallement further assert that astronomers are already very familiar with the source of this matter.

    For 70 years, scientists have known that analysis of stellar spectra indicates unknown absorptions, throughout interstellar space, at specific wavelengths called the diffuse interstellar bands (DIBs). DIBs are attributed to complex organic molecules that American astrophysicist Theodore Snow believes may constitute the largest known reservoir of organic matter in the universe. This interstellar organic material is usually found in the same proportions. However, very dense clouds of matter like presolar nebulae are exceptions. In the middle of these nebulae, where matter is even denser, DIB absorptions plateau or even drop. This is because the organic molecules responsible for DIBs clump together there. The clumped matter absorbs less radiation than when it floated freely in space.

    Such primitive nebulae end up contracting to form a solar system like our own, with planets . . . and comets. The Rosetta mission taught us that comet nuclei form by gentle accretion of grains progressively greater in size. First, small particles stick together to form larger grains. These in turn combine to form still larger chunks, and so on, until we have a comet nucleus a few kilometers wide.

    Thus, the organic molecules that formerly populated the primitive nebulae—and that are responsible for DIBs—were probably not destroyed, but instead incorporated into the grains making up cometary nuclei. And there they have remained for 4.6 billion years. A sample-return mission would allow laboratory analysis of cometary organic material and finally reveal the identity of the mysterious interstellar matter underlying observed patterns in stellar spectra.

    If cometary organic molecules were indeed produced in interstellar space—and if they played a role in the emergence of life on our planet, as scientists believe today—might they not also have seeded life on many other planets of our galaxy?

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
    Information, communication and knowledge
    Environment, energy and sustainable development
    Nanosciences, nanotechnologies, materials
    Astroparticles: from particles to the Universe

     
  • richardmitnick 7:50 am on December 31, 2016 Permalink | Reply
    Tags: , , , CNRS, GANIL, , , , SPIRAL2   

    From CNRS: “At the Heart of Nuclear Matter with SPIRAL2” 

    CNRS bloc

    The National Center for Scientific Research

    11.14.2016
    Yaroslav Pigenet

    1
    View of part of the high energy transmission line of Spiral2 which makes it possible to focus the ion beams inside the tubes kept under high vacuum. 2. STROPPA/CEA/CNRS

    A new heavy-ion accelerator was inaugurated at the GANIL facility in Caen (northwestern France). The first phase in the SPIRAL2 project, this new instrument will enable scientists to delve further into the mysteries of the atom and even create new elements.

    3
    3

    In days of old, alchemists pursued a goal long believed illusory, that of transmuting a base metal into another—preferably noble. Today, at facilities like the French Large Heavy-ion Accelerator (GANIL) in Caen, the alchemists’ dream has become scientific reality. For the last 35 years, GANIL’s physicists have been smashing accelerated ions in order to produce new atoms and find the secrets of matter on atomic scales. Once the facilities of GANIL’s SPIRAL2 project (2nd generation Production System of Online Accelerated Radioactive Ions) are up and running, scientists will be able to perform transmutation on an unprecedented scale, opening the way to the discovery of as yet unknown elements and atomic structures.

    One of the world’s largest ion accelerators

    GANIL was jointly set up in 1976 by the French Alternative Energies and Atomic Energy Commission (CEA) and the CNRS National Institute of Nuclear and Particle Physics (IN2P3).1 In the years that followed, the facility continued to expand, establishing international collaborations and acquiring new equipment. This constant evolution, in which SPIRAL2 is a milestone, made it one of the world’s four leading laboratories in the field of ion beam research. Its operating principle has nonetheless remained the same: the production of electrically charged ions by stripping electrons from neutral atoms. When they enter the accelerator’s magnetic fields, the nuclei of these atoms near a third of the speed of light before smashing into the atomic nuclei in the target.

    These extremely high-energy collisions result in nuclear reactions that give rise to new nuclei with unusual neutron-proton ratios, structures or shapes. Observing and analyzing these short-lived radioactive nuclei helps scientists to gain a better grasp of the properties of nuclear matter. Thanks to the work of its 250 permanent staff (physicists, engineers, technicians, administrative staff, etc) and with the contribution of 700 visiting researchers from across the world, GANIL has witnessed a host of discoveries about the structure of atomic nuclei, their thermal and mechanical properties, and their decay modes.

    3
    The chart of nuclides. Each square represents a nucleus positioned according to its number of neutrons (on the horizontal x-axis) and protons (on the vertical y-axis). The white squares correspond to the 291 nuclei found in the natural state on Earth, while the orange and light grey areas show the 2 800 nuclei synthesized so far in the laboratory. Beyond feature the nuclei predicted by theory to exist in the Universe.

    The search for exotic nuclei

    The laboratory is at the cutting edge of research into exotic nuclei, so-called because they are not among the 291 stable isotopes found in the natural state on Earth. Over a hundred such nuclei have already been discovered, synthesized and studied. Once SPIRAL2 begins operation, it will become possible to produce and study new exotic nuclei at GANIL, enabling the facility to compete in the global race to produce super-heavy nuclei (nuclei with an atomic number, in other words number of protons, exceeding 110). For instance, GANIL will be able to produce new elements surpassing Oganesson (Og) the heaviest to date with 118 protons, and whose synthesis by a Russian laboratory was verified in December 2015.

    Buried nine meters underground, the various instruments making up the first phase of SPIRAL2 will begin operation progressively. They will not replace but rather extend GANIL’s existing facilities, whose area will increase from 11,000 m² to around 20,000 m². The project was divided into several phases so as to take budgetary constraints and safety clearance procedures into account.

    On November 3rd, 2016, the first phase, which is set to continue until 2019, will be marked by the inauguration of the brand new linear accelerator LINAC, and the two ion sources and injector that will feed into it.
    The first source will produce beams of heavy ions from elements ranging from carbon to uranium. “The heavy ion beams produced by this source will be ten to a hundred times more powerful than those currently available at GANIL,” explains Jean-Charles Thomas, a CNRS researcher at the site. “The beams will be used mainly to produce (exotic) radioactive nuclei by fusion reactions.”

    The second source will produce beams of lighter particles: protons, deuterons (nuclei made up of a proton and a neutron) and alpha particles (helium-4 nuclei, comprising two protons and two neutrons). “Beams of lightweight particles such as these are not currently available at GANIL,” Thomas points out. “They will be used principally to generate powerful beams of neutrons.” The beams of heavy ions or lightweight particles will then enter the radio-frequency quadrupole (RFQ), whose role is to accelerate the ions up to 4% of light speed, while separating them into packets suitable for injection into the accelerator.

    4
    The new LINAC accelerator comprises 19 cryomodules, each containing one or two acceleration cavities.
    2 P. STROPPA/CEA/CNRS

    From pure research to social applications

    At the heart of the SPIRAL2 facilities, the LINAC linear accelerator is made up of a sequence of 19 cryomodules containing superconducting cavities that operate at 4.5 K (-270 °C). The whole assembly will accelerate the particles to energies of up to 25% of the speed of light, while heavy ions will reach 18% of light speed. Depending on their nature, the high-energy beams will be sent to two new experimental areas, NFS (Neutrons For Science) and S3 (Super Separator Spectrometer), which are due to begin operation shortly.

    NFS, which will get underway in 2017, will be used to study the reactions brought about by fast neutrons in next-generation nuclear reactors, as well as the effects of neutron irradiation in the fields of healthcare and materials. The S3 area, due to become operational in 2019, will use beams of heavy ions to generate and study the exotic nuclei produced in nuclear fusion reactions.

    “In fundamental terms, SPIRAL2 let us elucidate the structure and behavior of atomic nuclei produced under extreme conditions,” says Julien Piot, a CNRS physicist involved with S3 at GANIL.”It should also confirm the existence of certain ‘magic numbers’ of protons/neutrons, as well as that of a possible island of stability for super-heavy nuclei.”

    However, SPIRAL2 will also have applications including the treatment of radioactive waste, the production of isotopes for nuclear medicine, and the study of the impact of neutrons on materials and living organisms.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
    Information, communication and knowledge
    Environment, energy and sustainable development
    Nanosciences, nanotechnologies, materials
    Astroparticles: from particles to the Universe

     
  • richardmitnick 12:47 pm on August 6, 2016 Permalink | Reply
    Tags: , CNRS, IRD, , Scientists are trying to build a colossal 'library of ice' before it all disappears   

    From Science Alert: “Scientists are trying to build a colossal ‘library of ice’ before it all disappears” 

    ScienceAlert

    Science Alert

    5 AUG 2016
    DAVID NIELD

    1
    CNRS/Bruno Jourdain

    So it’s come to this.

    The ongoing effects of climate change mean that the amount of ice covering Earth is shrinking, and a team of scientists has taken it upon themselves to store and catalogue as many types of as possible before it’s gone.

    You might not think that ice blocks from different parts of the world are all that different, but they contain invaluable data about long-term changes in the surrounding temperature and air quality – information that’s essential to understanding our planet.

    Researchers from the Protecting Ice Memory project, drawn from the IRD (Institut de Recherche pour le Développement), the CNRS (Centre National de la Recherche Scientifique) and the Université Grenoble Alpes in France, are launching the mission this month by taking a sample from the Mont Blanc massif in the Alps.

    “In the coming decades, or even centuries, this ice archive will be invaluable – be it for entirely unprecedented scientific discoveries or for understanding local changes in the environment,” said climatologist Jean Jouzel, former vice chair of the Intergovernmental Panel on Climate Change (IPCC).

    Once extracted, the blocks of ice are going to be transported through a ‘cold chain’ of ships and vehicles to an underground ice bunker at a research station in Antarctica.

    Eventually, the team wants to have several dozen ice cores, each measuring a hefty 130 metres in length, and stored in the snow cave at temperatures of –54°C. It’s been described by the scientists as “the most reliable and natural freezer in the world”.

    While the primary participants in the archive operation are from French institutions, the project was conceived of in Italy, and has received support from Germany, Austria, Switzerland, Brazil, the US, Russia, China, Nepal and Canada.

    The team says it was a sudden rise in glacier temperatures across the world that prompted them to take action, and the project was partly inspired by the ‘doomsday’ seed vault in Svalbard – a repository of millions of seeds collected from across the globe.

    The thinking behind the seed bank is that should any types of plant be wiped out, seeds from the vault can be used to restore them. In fact, some withdrawals have already been made for that very purpose.

    In a similar vein, keeping the enormous ice cores safe at the Concordia station in Antarctica will give researchers backup copies of the state of these glaciers that can be studied if something happens to the originals. Not only will they teach us more about the history of Earth’s climate, they could also point towards how it’s going to change in the future.

    The first three cylindrical cores are set to be extracted from the Col du Dôme – some 4,300 metres or 14,108 feet up Mount Blanc – on August 15. A helicopter will get them back down to the valley floor, and analysis on one core will begin immediately.

    “Our generation of scientists, which bears witness to global warming, has a particular responsibility to future generations,” said one of the project initiators, Carlo Barbante from the Ca’ Foscari University of Venice.

    Hopefully we just buckle down and start to take better care of our planet in the future, because all the libraries in the world can’t save us if we don’t.

    See the full article here

    See also the IRD article here .

    The CNRS .pdf is here .

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  • richardmitnick 8:42 am on July 14, 2016 Permalink | Reply
    Tags: , CNRS,   

    From CNRS: “Earthquake prediction : an innovative technique for monitoring submarine faults” Link to Science Paper Added 

    CNRS bloc

    The National Center for Scientific Research

    8 JULY 2016
    CNRS researcher
    Jean-Yves Royer
    T +33 (0)2 98 49 87 67
    jean-yves.royer@univ-brest.fr

    CNRS Press Office
    Priscilla Dacher
    T +33 (0)1 44 96 46 06
    priscilla.dacher@cnrs-dir.fr

    To monitor a segment of the North Anatolian seismic fault near Istanbul, an international team of researchers, in particular from CNRS and Université de Bretagne Occidentale, has installed a network of transponders on the floor of the Sea of Marmara. The aim is to measure motion of the sea floor on either side of this segment. The data collected during the first six months reveals that the fault is probably locked in the region of this segment, suggesting that there is a progressive build-up of energy that could be released suddenly. This could cause a major earthquake in the Istanbul area. The study, carried out by a collaboration of researchers from France, Germany and Turkey, is published in Geophysical Research Letters .

    1
    Rupture zones and years along the North Anatolian fault. The submarine segment south of Istanbul is not thought to have caused any major earthquakes since the 18th century. The black rectangle shows the area studied. © J-Y Royer / CNRS-UBO LDO.

    The North Anatolian fault, which caused destructive earthquakes in Turkey in 1999, is comparable to the San Andreas fault in California. It marks the boundary between the Eurasian and Anatolian tectonic plates, which move relative to each other at a speed of around 2 cm per year. The behavior of one underwater segment of the fault, located a few tens of kilometers from Istanbul in the Sea of Marmara, particularly intrigues researchers, since there has apparently been no seismic activity there since the eighteenth century. How does this segment behave? Does it continuously creep? Does it regularly give way, occasionally causing small, low-magnitude quakes? Or is it locked, making it likely that it will one day rupture and cause a major earthquake?

    2
    Layout of the network of acoustic transponders (French in red, German in yellow) in the Sea of Marmara, on either side of the submarine segment of the North Anatolian fault (NAF), whose assumed trace is shown by the dashed line. © J-Y Royer / CNRS-UBO LDO.

    Observing the motion of a submarine fault in situ over a period of several years is no easy matter. To meet this challenge, the researchers are testing an innovative underwater remote sensing method, using active, autonomous acoustic transponders remotely accessible from the sea surface. Placed on the sea floor on either side of the fault at a depth of 800 meters, the transponders take it in turns to interrogate each other in pairs, and measure the round-trip time of an acoustic signal between them. These time lapses are then converted into distances between the transponders. The variation in these distances over time is used to detect motion of the sea floor and any deformation of the network of transponders, and thus infer the displacement of the fault. Specifically, a network of ten French and German transponders was set up during an initial sea cruise1 in October 2014. The first six months of data (travel time, temperature, pressure and stability)2 have confirmed that the system is performing well. Following calculations, the data show no significant motion of the monitored fault, within the network’s resolution limits. The distances between the transponders, which are between 350 and 1700 meters apart, are measured with a resolution of 1.5 to 2.5 mm. The segment is therefore probably locked or nearly locked, and is accumulating stress that could trigger an earthquake. However, it will be necessary to acquire data for several years in order to confirm this observation or show that this part of the fault has a more complex behavior.

    Going beyond this specific demonstration, if this approach, known as acoustic seafloor geodesy, proves to be robust in the long term (in this case, three to five years are planned, within the limits of the autonomy of the batteries), it could be included within a permanent underwater observatory as an addition to other observations (seismology, gas bubble emission, etc) for in situ real-time monitoring of the activity of this particular fault, or of other active submarine faults elsewhere in the world.

    The work was carried out by the Laboratoire Domaines Océaniques3 (LDO, CNRS/Université de Bretagne Occidentale), in collaboration with the Laboratoire Littoral Environnement et Sociétés (CNRS/Université de La Rochelle), GEOMAR (Kiel, Germany), Centre Européen de Recherche et d’Enseignement de Géosciences de l’Environnement (CNRS/Collège de France/AMU/IRD), the IFREMER’s Laboratoire Géosciences Marines, the Eurasian Institute of Earth Sciences at the Istanbul Technical University (Turkey), and the Kandilli Observatory and Earthquake Research Institute at Bogazici University, Istanbul. This paper is dedicated to the memory of the Principal Investigator of the project, Anne Deschamps, CNRS researcher at LDO, who passed away shortly after leading the successful deployment of the acoustic transponders.

    See the full article here .

    Please help promote STEM in your local schools.

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    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
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  • richardmitnick 9:37 am on June 22, 2016 Permalink | Reply
    Tags: , , CNRS,   

    CNRS: “An ocean lies a few kilometers beneath Enceladus’s icy surface” 

    CNRS bloc

    The National Center for Scientific Research

    21 june 2016
    CNRS researcher l Gabriel Tobie l T + 33 (0)2 76 64 51 61 l gabriel.tobie@univ-nantes.fr
    CNRS Press Office l Alexiane Agullo l T +33 (0)1 44 96 43 90 l alexiane.agullo@cnrs-dir.fr

    With eruptions of ice and water vapor, and an ocean covered by an ice shell, Saturn’s moon Enceladus is one of the most fascinating in the Solar System, especially as interpretations of data provided by the Cassini spacecraft have been contradictory until now. An international team including researchers from the Laboratoire de Planétologie Géodynamique de Nantes (CNRS/Université de Nantes/Université d’Angers), Charles University in Prague, and the Royal Observatory of Belgium [1] recently proposed a new model that reconciles different data sets and shows that the ice shell at Enceladus’s south pole may be only a few kilometers thick. This suggests that there is a strong heat source in the interior of Enceladus, an additional factor supporting the possible emergence of life in its ocean. The study has just been published online on the website of Geophysical Research Letters [link is below].

    Initial interpretations of data from Cassini flybys of Enceladus estimated that the thickness of its ice shell ranged from 30 to 40 km at the south pole to 60 km at the equator.

    NASA/ESA/ASI Cassini Spacecraft
    NASA/ESA/ASI Cassini

    These models were unable to settle the question of whether or not its ocean extended beneath the entire ice shell. However, the discovery in 2015 of an oscillation in Enceladus’s rotation known as a libration, which is linked to tidal effects, suggests that it has a global ocean and a much thinner ice shell than predicted, with a mean thickness of around 20 km. Nonetheless, this thickness appeared to be inconsistent with other gravity and topography data.

    In order to reconcile the different constraints, the researchers propose a new model in which the top two hundred meters of the ice shell acts like an elastic shell. According to this study, Enceladus is made up successively of a rocky core with a radius of 185 km, and an internal ocean approximately 45 km deep, isolated from the surface by an ice shell with a mean thickness of around 20 km, except at the south pole where it is thought to be less than 5 km thick. In this model, the ocean beneath the ice makes up 40% of the total volume of the moon, while its salt content is estimated to be similar to that of Earth’s oceans.

    All this implies a new energy budget for Enceladus. Since a thinner ice shell retains less heat, the tidal effects caused by Saturn on the large fractures in the ice at the south pole are no longer enough to explain the strong heat flow affecting this region. The model therefore reinforces the idea that there is strong heat production in Enceladus’s deep interior that may power the hydrothermal vents on the ocean floor. Since complex organic molecules, whose precise composition remains unknown, have been detected in Enceladus’s jets, these conditions appear to be favorable to the emergence of life. The relative thinness of the ice shell at the south pole could also allow a future space exploration mission to gather data, in particular using radar, which would be far more reliable and easy to obtain than with the 40 km thick ice shell initially calculated. It looks as if Enceladus still has many secrets in store!


    Image showing the thickness of Enceladus’s ice shell, which reaches 35 kilometers in the cratered equatorial regions (shown in yellow) and less than 5 kilometers in the active south polar region (shown in blue). © LPG-CNRS-U. Nantes/U. Charles, Prague.

    Notes:

    1 And from the Instituut voor Sterrenkunde.
    Bibliography:

    Enceladus’s internal ocean and ice shell constrained from Cassini gravity, shape and libration data. Ondrej Cadek, Gabriel Tobie, Tim Van Hoolst, Marion Masse, Gael Choblet, Axel Lefevre, Giuseppe Mitri, Rose-Marie Baland, Marie Behounkova, Olivier Bourgeois, and Anthony Trinh. Geophysical Research Letters. On line 11 June 2016. DOI : http://onlinelibrary.wiley.com/doi/10.1002/2016GL068634/full

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
    Information, communication and knowledge
    Environment, energy and sustainable development
    Nanosciences, nanotechnologies, materials
    Astroparticles: from particles to the Universe

     
  • richardmitnick 9:03 am on April 22, 2016 Permalink | Reply
    Tags: , CNRS, Giant plankton,   

    From CNRS: “Giant plankton gains long-due attention” 

    CNRS bloc

    The National Center for Scientific Research

    21 April 2016
    CNRS researcher l
    Fabrice Not l
    T +33 (0)2 98 29 25 37 l
    not@sb-roscoff.fr

    CNRS press officer l
    Priscilla Dacher l
    T +33 (0)1 44 96 46 06 / 51 51 l
    priscilla.dacher@cnrs-dir.fr

    1
    Deployment of the underwater camera used in this study.© Rainer Kiko, GEOMAR

    A team of marine biologists and oceanographers from CNRS, UPMC1 and the German organization GEOMAR have revealed the importance in all the world’s oceans of a group of large planktonic organisms called Rhizaria, which had previously been completely underestimated. According to their findings, these organisms make up 33% of the total abundance of large zooplankton in the world’s oceans, and account for 5% of the overall marine biomass. The study was carried out on samples collected during eleven oceanographic campaigns (2008-2013) covering the world’s main oceanic regions, and included the Tara Oceans expedition. It is published on 20 April 2016 on the website of the journal Nature (print edition 28 April2 ).
    Although invisible to the naked eye, marine plankton play a key role in the balance of our planet. Still largely unexplored, they consist of an astonishingly wide variety of tiny organisms that produce half the Earth’s oxygen and form the base of the oceanic food chain that feeds fish and marine mammals. Rhizarians, from their Latin name Rhizaria, are a group of large planktonic organisms whose importance had been overlooked until now. Most estimates of the distribution of marine organisms are performed locally (in a defined marine area) and are based on collection with plankton nets. However carefully carried out, this operation can damage certain fragile organisms such as rhizarians, preventing their identification.

    Marine biologists and oceanographers have pooled their skills with the aim of analyzing samples collected during eleven oceanographic campaigns from 2008 to 2013, using a less destructive method, namely an underwater camera deployed at depth. This in situ imaging system, which involved no collection, was used to study the organisms directly in their environment without damaging them. In all, sampling was carried out at 877 stations (corresponding to 1 454 immersions of the camera down to 1 500 meters), covering the world’s main oceanic regions. In total, the scientists analyzed 1.8 million images in order to quantify the abundance and biomass represented by Rhizaria3.

    The results were surprising: their estimates unequivocally show that Rhizaria make up more than a quarter of the total abundance of the world’s large zooplankton. They also found that they account for 5% of the total biomass in the oceans (taking into account all organisms, from plankton to whales). The presence of Rhizaria in all the planet’s oceans had previously been completely overlooked. However, they are unevenly distributed: these giant plankton are predominant in the nutrient-poor regions (located at the center of the large oceans) that cover most of the ocean area. This distribution could be explained by Rhizaria’s ability to live in association (symbiosis) with microalgae, just like coral. In symbiosis, the partnership between organisms is based on mutual exchange of food: by directly benefiting from the products of photosynthesis, Rhizaria are able to survive in nutrient-deficient waters. Plankton are gradually giving up their secrets, unveiling unsuspected wealth and diversity.

    2
    Three rhizarians (Rhizaria) seen through an optical microscope. The small yellow dots seen around the periphery of the organisms are symbiotic algae. Each organism has an average size of 0.2 to 1 centimeter. These types of Rhizaria are solitary and do not form colonies. 3 rhizarians © Tristan Biard, Station biologique de Roscoff (CNRS/UPMC)

    3
    Overall view of rhizarians forming colonies (seen in optical microscopy). Each white dot is an individual member of the colony. The colonies can reach a size of several centimeters. They were collected in the Mediterranean by the Observatoire Océanologique de Villefranche-sur-Mer. © Christian Sardet, Observatoire Océanologique de Villefranche (CNRS/UPMC)

    4
    A large solitary rhizarian (Rhizaria) (around 0.5 cm) seen through an optical microscope. The small yellow dots seen around the periphery of the organism’s cell are symbiotic algae. © Tristan Biard, Station biologique de Roscoff (CNRS/UPMC)

    Notes:

    1 In the “Adaptation et Diversité en Milieu Marin” laboratory (CNRS/UPMC) at the Station Biologique de Roscoff and the Laboratoire d’Océanographie de Villefranche (CNRS/UPMC) located at the Observatoire Océanologique de Villefranche (southeastern France).
    2 This work will be published in the print edition in the same issue of Nature as the study carried out by Guidi et al. (View web site)
    3 Those considered in this article have a size comprised between 600 µm (0.6 mm) and a few centimeters (which is large for plankton). The smallest and largest Rhizaria are therefore not taken into account in this study. These estimates are therefore likely to considerably underestimate their real contribution to biomass.
    Bibliography:

    In situ imaging reveals the biomass of giant protists in the global ocean, Tristan Biard, Lars Stemmann, Marc Picheral, Nicolas Mayot, Pieter Vandromme, Helena Hauss, Gabriel Gorsky, Lionel Guidi, Rainer Kiko & Fabrice Not. Nature, 20 April 2016. doi: 10.1038/nature17652

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
    Information, communication and knowledge
    Environment, energy and sustainable development
    Nanosciences, nanotechnologies, materials
    Astroparticles: from particles to the Universe

     
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