We present the discovery from the TESS mission of two giant planets transiting M dwarf stars: TOI... more We present the discovery from the TESS mission of two giant planets transiting M dwarf stars: TOI 4201 b and TOI 5344 b. We also provide precise radial velocity measurements and updated system parameters for three other M dwarfs with transiting giant planets: TOI 519, TOI 3629 and TOI 3714. We measure planetary masses of 0.525 ± 0.064 M J , 0.243 ± 0.020 M J , 0.689 ± 0.030 M J , 2.57 ± 0.15 M J , and 0.412 ± 0.040 M J for TOI 519 b, TOI 3629 b, TOI 3714 b, TOI 4201 b, and TOI 5344 b, respectively. The corresponding stellar masses are 0.372 ± 0.018 M ⊙ , 0.635±0.032 M ⊙ , 0.522±0.028 M ⊙ , 0.625±0.033 M ⊙ and 0.612±0.034 M ⊙. All five hosts have super-solar metallicities, providing further support for recent findings that, like for solar-type stars, close-in giant planets are preferentially found around metal-rich M dwarf host stars. Finally, we describe a procedure for accounting for systematic errors in stellar evolution models when those models are included directly in fitting a transiting planet system.
HAL (Le Centre pour la Communication Scientifique Directe), Oct 16, 2016
Partnership, and the Vatican Observatory for the consistent allocation of telescope time over the... more Partnership, and the Vatican Observatory for the consistent allocation of telescope time over the last 12 years of this project.
Temperate Earth-sized exoplanets around late-M dwarfs offer a rare opportunity to explore under w... more Temperate Earth-sized exoplanets around late-M dwarfs offer a rare opportunity to explore under which conditions planets can develop hospitable climate conditions. The small stellar radius amplifies the atmospheric transit signature, making even compact secondary atmospheres dominated by N 2 or CO 2 amenable to characterization with existing instrumentation 1. Yet, despite large planet search efforts 2 , detection of low-temperature Earth-sized planets around late-M dwarfs has remained rare and the TRAPPIST-1 system, a resonance chain of rocky planets with seemingly identical compositions, has not yet shown any evidence of volatiles in the system 3. Here we report the discovery of a temperate Earth-sized planet orbiting the cool M6 dwarf LP 791-18. The newly discovered planet, LP 791-18d, has a radius of 1.03 ± 0.04 R ⊕ and an equilibrium temperature of 300-400 K, with the permanent night side plausibly allowing for water condensation. LP 791-18d is part of a coplanar system 4 and provides a so-far unique opportunity to investigate a temperate exo-Earth in a system with a sub-Neptune that retained its gas or volatile envelope. On the basis of observations of transit timing variations, we find a mass of 7.1 ± 0.7 M ⊕ for the sub-Neptune LP 791-18c and a mass of M 0.9 ⊕ −0.4 +0.5 for the exo-Earth LP 791-18d. The gravitational interaction with the sub-Neptune prevents the complete circularization of LP 791-18d's orbit, resulting in continued tidal heating of LP 791-18d's interior and probably strong volcanic activity at the surface 5,6. LP 791-18d was detected through 127 h of dedicated, near-continuous Spitzer observations of LP 791-18, one of the smallest stars known to host planets. LP 791-18 was previously known to host the hot super-Earth LP 791-18b on a 0.94-day orbit and the sub-Neptune LP 791-18c on a 4.99-day orbit, both discovered in June 2019 by the Transiting Exoplanet Survey Satellite (TESS) 4 , but both without radial-velocity confirmation or mass measurements. Two transits of the newly discovered LP 791-18d are clearly visible in the 127-hour-long Spitzer light curve (Fig. 1), in addition to transits of the previously known planets LP 791-18b and c. We subsequently confirmed LP 791-18d's ephemeris using ground-based telescopes and discovered that the new LP 791-18d opens the system to mass measurements through transit timing variations (TTVs). We therefore complemented our observations of this system with a large multi-year, multi-telescope transit campaign totalling 72 transit observations between 2019 and 2021 including 43 transits of the Earth-sized planet LP 791-18d and 29 transits of sub-Neptune LP 791-18c (Methods, Extended Data Tables 1 and 2 and Extended Data Fig. 1). Our detection of TTVs, further discussed below, confirms the planetary nature of the LP 791-18 transit events by evincing the mutual gravitational interaction between planets c and d.
Proceedings of the International Astronomical Union, 2005
This paper discusses the potential performances of interferometers at the Dome C site in the Anta... more This paper discusses the potential performances of interferometers at the Dome C site in the Antarctic. The work is focussed on the limiting performances for fringe tracking, considering different fringe trackers architectures. The fringe tracking limiting magnitude is combined with estimates of the isopistonic angle at Dome C to evaluate the possibilities of off axis fringe tracking. The first evaluations presented here indicate that the sky coverage with realistic off axis fringe tracking is quite high at Dome C even with modest individual apertures and this could finally the best and decisive advantage of this site for optical interferometry. This might make a Dome C interferometer an unique deep sky very high angular resolution machine.
International Journal of Computer Applications, 2014
As part of the Extremely Large Telescope (ELT) project, the sitetesting team at Morocco has measu... more As part of the Extremely Large Telescope (ELT) project, the sitetesting team at Morocco has measured from April 2008 to December 2009. The atmospheric properties at Aklim which was one of the candidates sites pre-selected. In this paper we present the isoplanatic angle θ 0 and the isopistonic angle θ p measurements at Aklim site. Statistics of the mentioned parameters are obtained from the whole data recorded using a Multi Aperture Scintillation Sensor (MASS) and a Differential Image Motion Monitor (DIMM) system. More representative results and statistics are shown hereafter.
When a projectile at hypervelocity impacts the Moon a transient luminous phenomenon occurs (impac... more When a projectile at hypervelocity impacts the Moon a transient luminous phenomenon occurs (impact flash). Here we report some results of the analysis of the two first lunar flashes detected from an astronomical observatory based in Morocco.
ABSTRACT When a projectile at hyper-velocity impacts the Moon a transient luminous phenomenon occ... more ABSTRACT When a projectile at hyper-velocity impacts the Moon a transient luminous phenomenon occurs (impact flash). Here we present the research environment of our network. We highlight some results of the analysis of the first Lunar Meteoroids impacts detected in Morocco. On February 6, 2013, at 06:29:56.7 UT and April 14, 2013, 20:00:45.4 we observed two flashes produced by kilogram-size meteoroids striking the lunar surface. In addition to providing intensity and duration of the flash, and estimates of the mass of the meteoroids, we report on the first developments of techniques to determine accurately the position of the flash.
ABSTRACT Morocco is known to a region of frequent witness of meteorite falls and/or recovery. Thi... more ABSTRACT Morocco is known to a region of frequent witness of meteorite falls and/or recovery. This dictate the necessity to create the first Moroccan meteor network. This paper presents the results of the 2012 Geminid observation campaign performed at the Atlas Golf Marrakesh, Marrakesh, Morocco. It was found that the Geminids duration is generally correlated to their magnitude. Moreover, we analyse a Geminid spectrum showing a normal class spectrum, with high sodium content. Morocco is found to be an excellent place for meteor observation and future work and collaboration are presented.
ABSTRACT In this paper we describe a new technique of circular aperture apodization. It is produc... more ABSTRACT In this paper we describe a new technique of circular aperture apodization. It is produced by interferometry. The light, which is diffracted by a circular aperture, is split into two beams of different amplitudes where one of them has undergone an homothety to change its radial dimensions, by using an afocal optical system. The two beams are then combined coherently to form an apodized point spread function (PSF). This procedure allows us to reduce the diffraction wings of the PSF with different reduction factors depending on the combination parameters.
In this paper we report the all exoplanets that are discovered to date by the transit method. Als... more In this paper we report the all exoplanets that are discovered to date by the transit method. Also, we present the limit of detection by this method using the small instruments, and the specific information that can be deducted from the transit method. In addition, we present the detection and characterization of HD 189733b, the peculiarity of this exoplanet is that the flow of the target star is decreased significantly (~3%) during the transit. We determined the radius of the exoplanet 1.27 ± 0.03 RJ, the impact parameter 0.70 ± 0.02, and the inclination of the orbit 85.4 ± 0.1°. The transit of the extrasolar planet HD 189733b is already done using the larger telescope. In this study, we used during the observation a telescope of modest size.
In this work we describe an apodization technique of a circular telescope aperture . The apodizat... more In this work we describe an apodization technique of a circular telescope aperture . The apodization procedure introduced here consists of splitting a PSF image into two PSF images, using optical systems, where one of them has undergone a homothety to change its radial dimensions. After a coherent recombination of these two PSFs, we obtain an apodized image. This procedure allows us to reduce the diffraction wings of the PSF with different reduction factors depending on the combination parameters. In laboratory this apodization aproach can be realized by using an interferometric assembly based on Mach-Zender interferometer . We present here the simulation results and we show that the technique HACA reduce the diffraction wings. This technique can be combined with coronagraphy.
ABSTRACT As part of the conceptual and preliminary design processes of the Extremely Large Telesc... more ABSTRACT As part of the conceptual and preliminary design processes of the Extremely Large Telescope (ELT), the ELT site-testing team at Morocco has spent the last two years measuring the atmospheric properties at Aklim site as another 4 candidate mountains in North and South hemisphere, Aklim is the per-selected site for the ELT, is located in Moroccan Anti-Atlas at the geographic coordinates 30°7'39" N, 08°18'39" W. In this paper we present the isoplanatic angle theta0 and the isopistonic angle thetap, measurements at Aklim site, statistics of the mentioned parameters are obtained from the whole data recorded from April 2008 to December 2009 using the Multi Aperture Scintillation Sensor (MASS) - Differential Image Motion Monitor (DIMM) system, more representative results and statistics are shown hereafter.
The ESO OWL site survey plan includes the analysis of the astronomical quality of the Atlas mount... more The ESO OWL site survey plan includes the analysis of the astronomical quality of the Atlas mountains in Morocco. In this paper we are preseningt the first long time measurement of optical turbulence at Oukaimeden site. For this work we built an instrument called ADIMM for an Automated Differencial Image Motion Monitor, and we use it to the measure the optical turbulence at the Oukaimeden Site. We are describing the instrument and reporting the first results obtained after six month of working on this project. The results of night-time seeing measurements carried out during the period from Jun 14 up to October 01 2003 are presented. The median and mean values of the seeing for the entire period of observations are respectively 0.75" and 0.84".
Proceedings of the International Astronomical Union, 2006
The ELT project is currently under way in Europe and North America. Astronomical sites depend cri... more The ELT project is currently under way in Europe and North America. Astronomical sites depend critically on sky transparency and on aerosol loadings. A quantitative survey of aerosol optical properties at candidate ELT sites is an essential part of the site selection process. There are basically two methods to characterize aerosol properties: ground based measurements and satellite measurements. In this paper we will establish a full climatology of two sites very close to each other, but at a difference of 2300m in altitude: Izaña and Santa Cruz located in the Canary Islands. Both have sun photometers from the AERONET network. We also use the aerosol index determined from TOMS satellite data to determine how aerosol optical properties vary with altitude. We establish a correlation between the TOMS index and the aerosol optical thickness in both sites. Aerosol optical properties show very good correlation between Izaña and Santa Cruz. As a result we establish a set of relationships h...
Monthly Notices of the Royal Astronomical Society, 2010
In this paper we describe a two-dimensional apodization of a circular aperture produced by interf... more In this paper we describe a two-dimensional apodization of a circular aperture produced by interferometry. The light that is diffracted by a circular aperture is split into two beams of different amplitudes, where one of them has undergone a homothety to change its radial dimensions using an afocal optical system. The two beams are then combined coherently to form an apodized point-spread function (PSF). This procedure allows us to reduce the diffraction wings of the PSF, with different reduction factors depending on the combination of parameters.
Monthly Notices of the Royal Astronomical Society, 2006
In this paper, we present a new method to estimate, for each turbulent layer labelled i, the hori... more In this paper, we present a new method to estimate, for each turbulent layer labelled i, the horizontal wind speed v(h i), the standard deviation of the horizontal wind speed fluctuations σ v (h i) and the integrated value of C 2 n over the thickness h i of the turbulent layer C 2 n (h i) h i , where h i is the altitude of the turbulent layer. These parameters are extracted from single star scintillation spatiotemporal cross-correlation functions of atmospheric speckles obtained within the generalized mode. This method is based on the simulated annealing algorithm to find the optimal solution required to solve the problem. Astrophysics parameters for adaptive optics are also calculated using C 2 n (h i) and v (h i) values. The results of other techniques support this new method.
We present here a report following the Second Arab Impact Cratering and Astrogeology Conference t... more We present here a report following the Second Arab Impact Cratering and Astrogeology Conference that took place in Casablanca in November 2011. It includes a summary of the main results presented at this meeting and recent developments in impact science in the Arab world. Known and potential impact structures in this region of the world are presented on a map. The conference ended with a synopsis and a list of recommendations that are reported here. We conclude with some remarkable aspects of the postconference field trip.
We present the discovery from the TESS mission of two giant planets transiting M dwarf stars: TOI... more We present the discovery from the TESS mission of two giant planets transiting M dwarf stars: TOI 4201 b and TOI 5344 b. We also provide precise radial velocity measurements and updated system parameters for three other M dwarfs with transiting giant planets: TOI 519, TOI 3629 and TOI 3714. We measure planetary masses of 0.525 ± 0.064 M J , 0.243 ± 0.020 M J , 0.689 ± 0.030 M J , 2.57 ± 0.15 M J , and 0.412 ± 0.040 M J for TOI 519 b, TOI 3629 b, TOI 3714 b, TOI 4201 b, and TOI 5344 b, respectively. The corresponding stellar masses are 0.372 ± 0.018 M ⊙ , 0.635±0.032 M ⊙ , 0.522±0.028 M ⊙ , 0.625±0.033 M ⊙ and 0.612±0.034 M ⊙. All five hosts have super-solar metallicities, providing further support for recent findings that, like for solar-type stars, close-in giant planets are preferentially found around metal-rich M dwarf host stars. Finally, we describe a procedure for accounting for systematic errors in stellar evolution models when those models are included directly in fitting a transiting planet system.
HAL (Le Centre pour la Communication Scientifique Directe), Oct 16, 2016
Partnership, and the Vatican Observatory for the consistent allocation of telescope time over the... more Partnership, and the Vatican Observatory for the consistent allocation of telescope time over the last 12 years of this project.
Temperate Earth-sized exoplanets around late-M dwarfs offer a rare opportunity to explore under w... more Temperate Earth-sized exoplanets around late-M dwarfs offer a rare opportunity to explore under which conditions planets can develop hospitable climate conditions. The small stellar radius amplifies the atmospheric transit signature, making even compact secondary atmospheres dominated by N 2 or CO 2 amenable to characterization with existing instrumentation 1. Yet, despite large planet search efforts 2 , detection of low-temperature Earth-sized planets around late-M dwarfs has remained rare and the TRAPPIST-1 system, a resonance chain of rocky planets with seemingly identical compositions, has not yet shown any evidence of volatiles in the system 3. Here we report the discovery of a temperate Earth-sized planet orbiting the cool M6 dwarf LP 791-18. The newly discovered planet, LP 791-18d, has a radius of 1.03 ± 0.04 R ⊕ and an equilibrium temperature of 300-400 K, with the permanent night side plausibly allowing for water condensation. LP 791-18d is part of a coplanar system 4 and provides a so-far unique opportunity to investigate a temperate exo-Earth in a system with a sub-Neptune that retained its gas or volatile envelope. On the basis of observations of transit timing variations, we find a mass of 7.1 ± 0.7 M ⊕ for the sub-Neptune LP 791-18c and a mass of M 0.9 ⊕ −0.4 +0.5 for the exo-Earth LP 791-18d. The gravitational interaction with the sub-Neptune prevents the complete circularization of LP 791-18d's orbit, resulting in continued tidal heating of LP 791-18d's interior and probably strong volcanic activity at the surface 5,6. LP 791-18d was detected through 127 h of dedicated, near-continuous Spitzer observations of LP 791-18, one of the smallest stars known to host planets. LP 791-18 was previously known to host the hot super-Earth LP 791-18b on a 0.94-day orbit and the sub-Neptune LP 791-18c on a 4.99-day orbit, both discovered in June 2019 by the Transiting Exoplanet Survey Satellite (TESS) 4 , but both without radial-velocity confirmation or mass measurements. Two transits of the newly discovered LP 791-18d are clearly visible in the 127-hour-long Spitzer light curve (Fig. 1), in addition to transits of the previously known planets LP 791-18b and c. We subsequently confirmed LP 791-18d's ephemeris using ground-based telescopes and discovered that the new LP 791-18d opens the system to mass measurements through transit timing variations (TTVs). We therefore complemented our observations of this system with a large multi-year, multi-telescope transit campaign totalling 72 transit observations between 2019 and 2021 including 43 transits of the Earth-sized planet LP 791-18d and 29 transits of sub-Neptune LP 791-18c (Methods, Extended Data Tables 1 and 2 and Extended Data Fig. 1). Our detection of TTVs, further discussed below, confirms the planetary nature of the LP 791-18 transit events by evincing the mutual gravitational interaction between planets c and d.
Proceedings of the International Astronomical Union, 2005
This paper discusses the potential performances of interferometers at the Dome C site in the Anta... more This paper discusses the potential performances of interferometers at the Dome C site in the Antarctic. The work is focussed on the limiting performances for fringe tracking, considering different fringe trackers architectures. The fringe tracking limiting magnitude is combined with estimates of the isopistonic angle at Dome C to evaluate the possibilities of off axis fringe tracking. The first evaluations presented here indicate that the sky coverage with realistic off axis fringe tracking is quite high at Dome C even with modest individual apertures and this could finally the best and decisive advantage of this site for optical interferometry. This might make a Dome C interferometer an unique deep sky very high angular resolution machine.
International Journal of Computer Applications, 2014
As part of the Extremely Large Telescope (ELT) project, the sitetesting team at Morocco has measu... more As part of the Extremely Large Telescope (ELT) project, the sitetesting team at Morocco has measured from April 2008 to December 2009. The atmospheric properties at Aklim which was one of the candidates sites pre-selected. In this paper we present the isoplanatic angle θ 0 and the isopistonic angle θ p measurements at Aklim site. Statistics of the mentioned parameters are obtained from the whole data recorded using a Multi Aperture Scintillation Sensor (MASS) and a Differential Image Motion Monitor (DIMM) system. More representative results and statistics are shown hereafter.
When a projectile at hypervelocity impacts the Moon a transient luminous phenomenon occurs (impac... more When a projectile at hypervelocity impacts the Moon a transient luminous phenomenon occurs (impact flash). Here we report some results of the analysis of the two first lunar flashes detected from an astronomical observatory based in Morocco.
ABSTRACT When a projectile at hyper-velocity impacts the Moon a transient luminous phenomenon occ... more ABSTRACT When a projectile at hyper-velocity impacts the Moon a transient luminous phenomenon occurs (impact flash). Here we present the research environment of our network. We highlight some results of the analysis of the first Lunar Meteoroids impacts detected in Morocco. On February 6, 2013, at 06:29:56.7 UT and April 14, 2013, 20:00:45.4 we observed two flashes produced by kilogram-size meteoroids striking the lunar surface. In addition to providing intensity and duration of the flash, and estimates of the mass of the meteoroids, we report on the first developments of techniques to determine accurately the position of the flash.
ABSTRACT Morocco is known to a region of frequent witness of meteorite falls and/or recovery. Thi... more ABSTRACT Morocco is known to a region of frequent witness of meteorite falls and/or recovery. This dictate the necessity to create the first Moroccan meteor network. This paper presents the results of the 2012 Geminid observation campaign performed at the Atlas Golf Marrakesh, Marrakesh, Morocco. It was found that the Geminids duration is generally correlated to their magnitude. Moreover, we analyse a Geminid spectrum showing a normal class spectrum, with high sodium content. Morocco is found to be an excellent place for meteor observation and future work and collaboration are presented.
ABSTRACT In this paper we describe a new technique of circular aperture apodization. It is produc... more ABSTRACT In this paper we describe a new technique of circular aperture apodization. It is produced by interferometry. The light, which is diffracted by a circular aperture, is split into two beams of different amplitudes where one of them has undergone an homothety to change its radial dimensions, by using an afocal optical system. The two beams are then combined coherently to form an apodized point spread function (PSF). This procedure allows us to reduce the diffraction wings of the PSF with different reduction factors depending on the combination parameters.
In this paper we report the all exoplanets that are discovered to date by the transit method. Als... more In this paper we report the all exoplanets that are discovered to date by the transit method. Also, we present the limit of detection by this method using the small instruments, and the specific information that can be deducted from the transit method. In addition, we present the detection and characterization of HD 189733b, the peculiarity of this exoplanet is that the flow of the target star is decreased significantly (~3%) during the transit. We determined the radius of the exoplanet 1.27 ± 0.03 RJ, the impact parameter 0.70 ± 0.02, and the inclination of the orbit 85.4 ± 0.1°. The transit of the extrasolar planet HD 189733b is already done using the larger telescope. In this study, we used during the observation a telescope of modest size.
In this work we describe an apodization technique of a circular telescope aperture . The apodizat... more In this work we describe an apodization technique of a circular telescope aperture . The apodization procedure introduced here consists of splitting a PSF image into two PSF images, using optical systems, where one of them has undergone a homothety to change its radial dimensions. After a coherent recombination of these two PSFs, we obtain an apodized image. This procedure allows us to reduce the diffraction wings of the PSF with different reduction factors depending on the combination parameters. In laboratory this apodization aproach can be realized by using an interferometric assembly based on Mach-Zender interferometer . We present here the simulation results and we show that the technique HACA reduce the diffraction wings. This technique can be combined with coronagraphy.
ABSTRACT As part of the conceptual and preliminary design processes of the Extremely Large Telesc... more ABSTRACT As part of the conceptual and preliminary design processes of the Extremely Large Telescope (ELT), the ELT site-testing team at Morocco has spent the last two years measuring the atmospheric properties at Aklim site as another 4 candidate mountains in North and South hemisphere, Aklim is the per-selected site for the ELT, is located in Moroccan Anti-Atlas at the geographic coordinates 30°7'39" N, 08°18'39" W. In this paper we present the isoplanatic angle theta0 and the isopistonic angle thetap, measurements at Aklim site, statistics of the mentioned parameters are obtained from the whole data recorded from April 2008 to December 2009 using the Multi Aperture Scintillation Sensor (MASS) - Differential Image Motion Monitor (DIMM) system, more representative results and statistics are shown hereafter.
The ESO OWL site survey plan includes the analysis of the astronomical quality of the Atlas mount... more The ESO OWL site survey plan includes the analysis of the astronomical quality of the Atlas mountains in Morocco. In this paper we are preseningt the first long time measurement of optical turbulence at Oukaimeden site. For this work we built an instrument called ADIMM for an Automated Differencial Image Motion Monitor, and we use it to the measure the optical turbulence at the Oukaimeden Site. We are describing the instrument and reporting the first results obtained after six month of working on this project. The results of night-time seeing measurements carried out during the period from Jun 14 up to October 01 2003 are presented. The median and mean values of the seeing for the entire period of observations are respectively 0.75" and 0.84".
Proceedings of the International Astronomical Union, 2006
The ELT project is currently under way in Europe and North America. Astronomical sites depend cri... more The ELT project is currently under way in Europe and North America. Astronomical sites depend critically on sky transparency and on aerosol loadings. A quantitative survey of aerosol optical properties at candidate ELT sites is an essential part of the site selection process. There are basically two methods to characterize aerosol properties: ground based measurements and satellite measurements. In this paper we will establish a full climatology of two sites very close to each other, but at a difference of 2300m in altitude: Izaña and Santa Cruz located in the Canary Islands. Both have sun photometers from the AERONET network. We also use the aerosol index determined from TOMS satellite data to determine how aerosol optical properties vary with altitude. We establish a correlation between the TOMS index and the aerosol optical thickness in both sites. Aerosol optical properties show very good correlation between Izaña and Santa Cruz. As a result we establish a set of relationships h...
Monthly Notices of the Royal Astronomical Society, 2010
In this paper we describe a two-dimensional apodization of a circular aperture produced by interf... more In this paper we describe a two-dimensional apodization of a circular aperture produced by interferometry. The light that is diffracted by a circular aperture is split into two beams of different amplitudes, where one of them has undergone a homothety to change its radial dimensions using an afocal optical system. The two beams are then combined coherently to form an apodized point-spread function (PSF). This procedure allows us to reduce the diffraction wings of the PSF, with different reduction factors depending on the combination of parameters.
Monthly Notices of the Royal Astronomical Society, 2006
In this paper, we present a new method to estimate, for each turbulent layer labelled i, the hori... more In this paper, we present a new method to estimate, for each turbulent layer labelled i, the horizontal wind speed v(h i), the standard deviation of the horizontal wind speed fluctuations σ v (h i) and the integrated value of C 2 n over the thickness h i of the turbulent layer C 2 n (h i) h i , where h i is the altitude of the turbulent layer. These parameters are extracted from single star scintillation spatiotemporal cross-correlation functions of atmospheric speckles obtained within the generalized mode. This method is based on the simulated annealing algorithm to find the optimal solution required to solve the problem. Astrophysics parameters for adaptive optics are also calculated using C 2 n (h i) and v (h i) values. The results of other techniques support this new method.
We present here a report following the Second Arab Impact Cratering and Astrogeology Conference t... more We present here a report following the Second Arab Impact Cratering and Astrogeology Conference that took place in Casablanca in November 2011. It includes a summary of the main results presented at this meeting and recent developments in impact science in the Arab world. Known and potential impact structures in this region of the world are presented on a map. The conference ended with a synopsis and a list of recommendations that are reported here. We conclude with some remarkable aspects of the postconference field trip.
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Papers by Zouhair Benkhaldoun