8 research outputs found

    New Technology Solar Coronagraphs

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    We present the Mirror Advanced technology Coronagraph (MAC) as a new generation solar telescope to be put at suitable high altitude coronal sites in order to resolve modern problems of solar physics, like the origin of the heating of the chromosphere and of the corona, the analysis of the mesospheric layers of the solar atmosphere and the effects of shearing the photospheric magnetic fields on the dynamics of the upper coronal layers

    Analysis of broad-band H

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    Context.Daily broad-band full-limb Hα images of the inner corona were obtained during solar cycle 23 (1994–2005) using the 15 cm Pic-du-Midi coronagraph. Aims.We want to automatically extract the properties and evolutions of the observed cool HI coronal structures over a wide range of sizes and light fluxes, from small jets and/or spikes to large prominences. Methods.A tool was developed to process the complete set of stored images. This paper describes the recognition techniques implemented in our software and discusses its use. It includes the removal of the parasitic diffraction ring produced by the set of different occulting disks used throughout the year. Results.We present and discuss selected results from a statistical analysis of the occurrence of parameters characterizing the observed structures applied to a large sample of observations. It illustrates the capabilities of this software when applied to our database. Strong asymmetries of the activity level over the solar poles become evident, confirming similar results from previous works. We also discuss the distribution of relative light fluxes of these structures over a wide range of sizes. Conclusions.The complete series of FITS and calibrated images, the list of the detected structures, and their geometric and luminosity evolutions are stored in the BASS2000 solar database catalogue (http://bass2000.bagn.obs-mip.f

    Analysis of broad-band H? coronagraphic observations

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    International audienceContext: Daily broad-band full-limb H? images of the inner corona were obtained during solar cycle 23 (1994-2005) using the 15 cm Pic-du-Midi coronagraph. Aims: We want to automatically extract the properties and evolutions of the observed cool HI coronal structures over a wide range of sizes and light fluxes, from small jets and/or spikes to large prominences. Methods: A tool was developed to process the complete set of stored images. This paper describes the recognition techniques implemented in our software and discusses its use. It includes the removal of the parasitic diffraction ring produced by the set of different occulting disks used throughout the year. Results: We present and discuss selected results from a statistical analysis of the occurrence of parameters characterizing the observed structures applied to a large sample of observations. It illustrates the capabilities of this software when applied to our database. Strong asymmetries of the activity level over the solar poles become evident, confirming similar results from previous works. We also discuss the distribution of relative light fluxes of these structures over a wide range of sizes. Conclusions: The complete series of FITS and calibrated images, the list of the detected structures, and their geometric and luminosity evolutions are stored in the BASS2000 solar database catalogue (http://bass2000.bagn.obs-mip.fr) and are made publicly available. The H? HI structures observed over the limb of the sun present statistical properties of great interest for understanding its eruptive activity

    FRIPON: A worldwide network to track incoming meteoroids

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    Context. Until recently, camera networks designed for monitoring fireballs worldwide were not fully automated, implying that in case of a meteorite fall, the recovery campaign was rarely immediate. This was an important limiting factor as the most fragile - hence precious - meteorites must be recovered rapidly to avoid their alteration. Aims. The Fireball Recovery and InterPlanetary Observation Network (FRIPON) scientific project was designed to overcome this limitation. This network comprises a fully automated camera and radio network deployed over a significant fraction of western Europe and a small fraction of Canada. As of today, it consists of 150 cameras and 25 European radio receivers and covers an area of about 1.5 × 106km2. Methods. The FRIPON network, fully operational since 2018, has been monitoring meteoroid entries since 2016, thereby allowing the characterization of their dynamical and physical properties. In addition, the level of automation of the network makes it possible to trigger a meteorite recovery campaign only a few hours after it reaches the surface of the Earth. Recovery campaigns are only organized for meteorites with final masses estimated of at least 500 g, which is about one event per year in France. No recovery campaign is organized in the case of smaller final masses on the order of 50 to 100 g, which happens about three times a year; instead, the information is delivered to the local media so that it can reach the inhabitants living in the vicinity of the fall. Results. Nearly 4000 meteoroids have been detected so far and characterized by FRIPON. The distribution of their orbits appears to be bimodal, with a cometary population and a main belt population. Sporadic meteors amount to about 55% of all meteors. A first estimate of the absolute meteoroid flux (mag < -5; meteoroid size ≥∼1 cm) amounts to 1250/yr/106km2. This value is compatible with previous estimates. Finally, the first meteorite was recovered in Italy (Cavezzo, January 2020) thanks to the PRISMA network, a component of the FRIPON science project

    FRIPON: A worldwide network to track incoming meteoroids

    No full text
    Context. Until recently, camera networks designed for monitoring fireballs worldwide were not fully automated, implying that in case of a meteorite fall, the recovery campaign was rarely immediate. This was an important limiting factor as the most fragile - hence precious - meteorites must be recovered rapidly to avoid their alteration. Aims. The Fireball Recovery and InterPlanetary Observation Network (FRIPON) scientific project was designed to overcome this limitation. This network comprises a fully automated camera and radio network deployed over a significant fraction of western Europe and a small fraction of Canada. As of today, it consists of 150 cameras and 25 European radio receivers and covers an area of about 1.5 × 106km2. Methods. The FRIPON network, fully operational since 2018, has been monitoring meteoroid entries since 2016, thereby allowing the characterization of their dynamical and physical properties. In addition, the level of automation of the network makes it possible to trigger a meteorite recovery campaign only a few hours after it reaches the surface of the Earth. Recovery campaigns are only organized for meteorites with final masses estimated of at least 500 g, which is about one event per year in France. No recovery campaign is organized in the case of smaller final masses on the order of 50 to 100 g, which happens about three times a year; instead, the information is delivered to the local media so that it can reach the inhabitants living in the vicinity of the fall. Results. Nearly 4000 meteoroids have been detected so far and characterized by FRIPON. The distribution of their orbits appears to be bimodal, with a cometary population and a main belt population. Sporadic meteors amount to about 55% of all meteors. A first estimate of the absolute meteoroid flux (mag < -5; meteoroid size ≥∼1 cm) amounts to 1250/yr/106km2. This value is compatible with previous estimates. Finally, the first meteorite was recovered in Italy (Cavezzo, January 2020) thanks to the PRISMA network, a component of the FRIPON science project

    FRIPON: a worldwide network to track incoming meteoroids

    No full text
    (IF 5.80; Q1)International audienceContext. Until recently, camera networks designed for monitoring fireballs worldwide were not fully automated, implying that in case of a meteorite fall, the recovery campaign was rarely immediate. This was an important limiting factor as the most fragile-hence precious-meteorites must be recovered rapidly to avoid their alteration. Aims. The Fireball Recovery and InterPlanetary Observation Network (FRIPON) scientific project was designed to overcome this limitation. This network comprises a fully automated camera and radio network deployed over a significant fraction of western Europe and a small fraction of Canada. As of today, it consists of 150 cameras and 25 European radio receivers and covers an area of about 1.5 × 10 6 km 2. Methods. The FRIPON network, fully operational since 2018, has been monitoring meteoroid entries since 2016, thereby allowing the characterization of their dynamical and physical properties. In addition, the level of automation of the network makes it possible to trigger a meteorite recovery campaign only a few hours after it reaches the surface of the Earth. Recovery campaigns are only organized for meteorites with final masses estimated of at least 500 g, which is about one event per year in France. No recovery campaign is organized in the case of smaller final masses on the order of 50 to 100 g, which happens about three times a year; instead, the information is delivered to the local media so that it can reach the inhabitants living in the vicinity of the fall. Results. Nearly 4000 meteoroids have been detected so far and characterized by FRIPON. The distribution of their orbits appears to be bimodal, with a cometary population and a main belt population. Sporadic meteors amount to about 55% of all meteors. A first estimate of the absolute meteoroid flux (mag <-5; meteoroid size ≥∼1 cm) amounts to 1250/yr/10 6 km 2. This value is compatible with previous estimates. Finally, the first meteorite was recovered in Italy (Cavezzo, January 2020) thanks to the PRISMA network, a component of the FRIPON science project

    FRIPON: a worldwide network to track incoming meteoroids

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    Context: Until recently, camera networks designed for monitoring fireballs worldwide were not fully automated, implying that in case of a meteorite fall, the recovery campaign was rarely immediate. This was an important limiting factor as the most fragile – hence precious – meteorites must be recovered rapidly to avoid their alteration. Aims: The Fireball Recovery and InterPlanetary Observation Network (FRIPON) scientific project was designed to overcome this limitation. This network comprises a fully automated camera and radio network deployed over a significant fraction of western Europe and a small fraction of Canada. As of today, it consists of 150 cameras and 25 European radio receivers and covers an area of about 1.5 × 106 km2. Methods: The FRIPON network, fully operational since 2018, has been monitoring meteoroid entries since 2016, thereby allowing the characterization of their dynamical and physical properties. In addition, the level of automation of the network makes it possible to trigger a meteorite recovery campaign only a few hours after it reaches the surface of the Earth. Recovery campaigns are only organized for meteorites with final masses estimated of at least 500 g, which is about one event per year in France. No recovery campaign is organized in the case of smaller final masses on the order of 50 to 100 g, which happens about three times a year; instead, the information is delivered to the local media so that it can reach the inhabitants living in the vicinity of the fall. Results: Nearly 4000 meteoroids have been detected so far and characterized by FRIPON. The distribution of their orbits appears to be bimodal, with a cometary population and a main belt population. Sporadic meteors amount to about 55% of all meteors. A first estimate of the absolute meteoroid flux (mag < –5; meteoroid size ≥~1 cm) amounts to 1250/yr/106 km2. This value is compatible with previous estimates. Finally, the first meteorite was recovered in Italy (Cavezzo, January 2020) thanks to the PRISMA network, a component of the FRIPON science project
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