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110. The PLATO 2.0 mission

Author

Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences, Valencia, Diana, Rauer, H., Catala, C., Aerts, C., Appourchaux, T., Benz, W., Brandeker, A., Christensen-Dalsgaard, J., Deleuil, M., Gizon, L., Goupil, M.-J., Güdel, M., Janot-Pacheco, E., Mas-Hesse, M., Pagano, I., Piotto, G., Pollacco, D., Santos, Ċ., Smith, A., Suárez, J.-C., Szabó, R., Udry, S., Adibekyan, V., Alibert, Y., Almenara, J.-M., Amaro-Seoane, P., Eiff, M. A, Asplund, M., Antonello, E., Barnes, S., Baudin, F., Belkacem, K., Bergemann, M., Bihain, G., Birch, A. C, Bonfils, X., Boisse, I., Bonomo, A. S, Borsa, F., Brandão, I. M, Brocato, E., Brun, S., Burleigh, M., Burston, R., Cabrera, J., Cassisi, S., Chaplin, W., Charpinet, S., Chiappini, C., Church, R. P, Csizmadia, Sz., Cunha, M., Damasso, M., Davies, M. B, Deeg, H. J, Díaz, R. F, Dreizler, S., Dreyer, C., Eggenberger, P., Ehrenreich, D., Eigmüller, P., Erikson, A., Farmer, R., Feltzing, S., Oliveira Fialho, F. d, Figueira, P., Forveille, T., Fridlund, M., García, R. A, Giommi, P., Giuffrida, G., Godolt, M., da Silva, J. G, Granzer, T., Grenfell, J. L, Grotsch-Noels, A., Günther, E., Haswell, C. A, Hatzes, A. P, Hébrard, G., Hekker, S., Helled, R., Heng, K., Jenkins, J. M, Johansen, A., Khodachenko, M. L, Kislyakova, K. G, Kley, W., Kolb, U., Krivova, N., Kupka, F., Lammer, H., Lanza, A. F, Lebreton, Y., Magrin, D., Marcos-Arenal, P., Marrese, P. M, Marques, J. P, Martins, J., Mathis, S., Mathur, S., Messina, S., Miglio, A., Montalban, J., Montalto, M., P. F. G. Monteiro, M. J, Moradi, H., Moravveji, E., Mordasini, C., Morel, T., Mortier, A., Nascimbeni, V., Nelson, R. P, Nielsen, M. B, Noack, L., Norton, A. J, Ofir, A., Oshagh, M., Ouazzani, R.-M., Pápics, P., Parro, V. C, Petit, P., Plez, B., Poretti, E., Quirrenbach, A., Ragazzoni, R., Raimondo, G., Rainer, M., Reese, D. R, Redmer, R., Reffert, S., Rojas-Ayala, B., Roxburgh, I. W, Salmon, S., Santerne, A., Schneider, J., Schou, J., Schuh, S., Schunker, H., Silva-Valio, A., Silvotti, R., Skillen, I., Snellen, I., Sohl, F., Sousa, S. G, Sozzetti, A., Stello, D., Strassmeier, K. G, Švanda, M., Szabó, Gy. M, Tkachenko, A., Van Grootel, V., Vauclair, S. D, Ventura, P., Wagner, F. W, Walton, N. A, Weingrill, J., Werner, S. C, Wheatley, P. J, Zwintz, K., Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences, Valencia, Diana, Rauer, H., Catala, C., Aerts, C., Appourchaux, T., Benz, W., Brandeker, A., Christensen-Dalsgaard, J., Deleuil, M., Gizon, L., Goupil, M.-J., Güdel, M., Janot-Pacheco, E., Mas-Hesse, M., Pagano, I., Piotto, G., Pollacco, D., Santos, Ċ., Smith, A., Suárez, J.-C., Szabó, R., Udry, S., Adibekyan, V., Alibert, Y., Almenara, J.-M., Amaro-Seoane, P., Eiff, M. A, Asplund, M., Antonello, E., Barnes, S., Baudin, F., Belkacem, K., Bergemann, M., Bihain, G., Birch, A. C, Bonfils, X., Boisse, I., Bonomo, A. S, Borsa, F., Brandão, I. M, Brocato, E., Brun, S., Burleigh, M., Burston, R., Cabrera, J., Cassisi, S., Chaplin, W., Charpinet, S., Chiappini, C., Church, R. P, Csizmadia, Sz., Cunha, M., Damasso, M., Davies, M. B, Deeg, H. J, Díaz, R. F, Dreizler, S., Dreyer, C., Eggenberger, P., Ehrenreich, D., Eigmüller, P., Erikson, A., Farmer, R., Feltzing, S., Oliveira Fialho, F. d, Figueira, P., Forveille, T., Fridlund, M., García, R. A, Giommi, P., Giuffrida, G., Godolt, M., da Silva, J. G, Granzer, T., Grenfell, J. L, Grotsch-Noels, A., Günther, E., Haswell, C. A, Hatzes, A. P, Hébrard, G., Hekker, S., Helled, R., Heng, K., Jenkins, J. M, Johansen, A., Khodachenko, M. L, Kislyakova, K. G, Kley, W., Kolb, U., Krivova, N., Kupka, F., Lammer, H., Lanza, A. F, Lebreton, Y., Magrin, D., Marcos-Arenal, P., Marrese, P. M, Marques, J. P, Martins, J., Mathis, S., Mathur, S., Messina, S., Miglio, A., Montalban, J., Montalto, M., P. F. G. Monteiro, M. J, Moradi, H., Moravveji, E., Mordasini, C., Morel, T., Mortier, A., Nascimbeni, V., Nelson, R. P, Nielsen, M. B, Noack, L., Norton, A. J, Ofir, A., Oshagh, M., Ouazzani, R.-M., Pápics, P., Parro, V. C, Petit, P., Plez, B., Poretti, E., Quirrenbach, A., Ragazzoni, R., Raimondo, G., Rainer, M., Reese, D. R, Redmer, R., Reffert, S., Rojas-Ayala, B., Roxburgh, I. W, Salmon, S., Santerne, A., Schneider, J., Schou, J., Schuh, S., Schunker, H., Silva-Valio, A., Silvotti, R., Skillen, I., Snellen, I., Sohl, F., Sousa, S. G, Sozzetti, A., Stello, D., Strassmeier, K. G, Švanda, M., Szabó, Gy. M, Tkachenko, A., Van Grootel, V., Vauclair, S. D, Ventura, P., Wagner, F. W, Walton, N. A, Weingrill, J., Werner, S. C, Wheatley, P. J, and Zwintz, K.

Abstract

PLATO 2.0 has recently been selected for ESA’s M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses fundamental questions such as: How do planetary systems form and evolve? Are there other systems with planets like ours, including potentially habitable planets? The PLATO 2.0 instrument consists of 34 small aperture telescopes (32 with 25 s readout cadence and 2 with 2.5 s candence) providing a wide field-of-view (2232 deg 2) and a large photometric magnitude range (4–16 mag). It focusses on bright (4–11 mag) stars in wide fields to detect and characterize planets down to Earth-size by photometric transits, whose masses can then be determined by ground-based radial-velocity follow-up measurements. Asteroseismology will be performed for these bright stars to obtain highly accurate stellar parameters, including masses and ages. The combination of bright targets and asteroseismology results in high accuracy for the bulk planet parameters: 2 %, 4–10 % and 10 % for planet radii, masses and ages, respectively. The planned baseline observing strategy includes two long pointings (2–3 years) to detect and bulk characterize planets reaching into the habitable zone (HZ) of solar-like stars and an additional step-and-stare phase to cover in total about 50 % of the sky. PLATO 2.0 will observe up to 1,000,000 stars and detect and characterize hundreds of small planets, and thousands of planets in the Neptune to gas giant regime out to the HZ. It will therefore provide the first large-scale catalogue of bulk characterized planets with accurate radii, masses, mean densities and ages. This catalogue will include terrestrial planets at intermediate orbital distances, where surface temperatures are moderate. Coverage of this parameter range with statistical numbers of bulk characterized planets is unique to PLATO 2.0. The PLATO 2.0 catalogue allows us to e.g.: - complete our knowledge of planet di

Published
2017

114. Self-consistent modelling of Mercury’s surface composition and exosphere by solar wind sputtering

Author

Lammer, H., Pleger, M., Wurz, P., Martín Fernández, J.A., Lichtenegger, H.I.M., and Khodachenko, M. L.

Subjects
Quantitative research, Investigació quantitativa, Matemàtiques i estadística::Estadística matemàtica [Àrees temàtiques de la UPC], Data analytics
Abstract

A Monte-Carlo model of exospheres was extended by treating the solar wind ion induced sputtering process, quantitatively in a self-consistent way starting with the actual release of particles from the mineral surface of Mercury. Mercury is a body without a significant atmosphere, thus, the surface is effected by different processes that are mainly related to the radiation and plasma environment of the Sun and to micrometeorites, which are delivered to Mercury’s surface. In such a case it can be assumed that the composition of Mercury’s thin collisionless atmosphere, the exosphere, is related to the composition of the planetary crustal materials. If so, then inferences regarding the bulk chemistry of the planet can be made from a study of atoms and molecules in the exosphere after they are released from the mineral surface by a variety of release processes. One difficult challenge is the identification of the main source of some elements like H, He, Na or K. Generally it is believed that H and He come primarily from the solar wind, while Na and K originate from volatilized materials partitioned between Mercury’s crust and impacts from meteorites. Besides the before mentioned elements corresponding to spectroscopic observations and experiments with soil analogues, other elements such as O, Na, Mg, Al, Si, P, S, K, Ca, Ti, Cr, Fe, Ni, Zn, OH should also be related with Mercury’s surface soils (Wurz et al., 2010, and references therein). Based on available observational data and literature data we established a global model for the surface mineralogy of Mercury and from that derived the average elemental composition of the surface. Compositional data analysis has been employed for Mercury’s surface minerals recently by (Sprague et al., 2009). In these cases the applied method was based on simple correlation methods, which do not exploit the full potential of the available data. In addition, the closed nature of compositional data, i.e., the assumption that component concentrations have to sum up to 100% in an analysis, bears important implications for the statistical analysis of compositional data, which do not seem to have been sufficiently appreciated until now. To investigate the default of the classical additive analysis method our research group applied recently a more realistic multiplicative method (Aitchison, 1986) based on the Euclidean space geometry of the simplex (see the chapter Elements of simplicial linear algebra and geometry). Our recent results presented in detail in Wurz et al., (2010) for Mercury will be discussed. This model serves as a tool to estimate densities of species in the exosphere depending on the release mechanism and the associated physical parameters quantitatively describing the particle release from the surface.

Published
2011

119. The PLATO 2.0 mission

Author

Rauer, H., Catala, C., Aerts, C., Appourchaux, T., Benz, W., Brandeker, Aexis, Christensen-Dalsgaard, J., Deleuil, M., Gizon, L., Goupil, M. -J, Guedel, M., Janot-Pacheco, E., Mas-Hesse, M., Pagano, I., Piotto, G., Pollacco, D., Santos, N. C., Smith, A., Suarez, J. -C, Szabo, R., Udry, S., Adibekyan, V., Alibert, Y., Almenara, J. -M, Maro-Seoane, P. A., Ammler-von Eiff, M., Asplund, M., Antonello, E., Barnes, S., Baudin, F., Belkacem, K., Bergemann, M., Bihain, G., Birch, A. C., Bonfils, X., Boisse, I., Bonomo, A. S., Borsa, F., Brandao, I. M., Brocato, E., Brun, S., Burleigh, M., Burston, R., Cabrera, J., Cassisi, S., Chaplin, W., Charpinet, S., Chiappini, C., Church, R. P., Csizmadia, Sz., Cunha, M., Damasso, M., Davies, M. B., Deeg, H. J., Diaz, R. F., Dreizler, S., Dreyer, C., Eggenberger, P., Ehrenreich, D., Eigmueller, P., Erikson, A., Farmer, R., Feltzing, S., de Oliveira Fialho, F., Figueira, P., Forveille, T., Fridlund, M., Garcia, R. A., Giommi, P., Giuffrida, G., Godolt, M., Gomes da Silva, J., Granzer, T., Grenfell, J. L., Grotsch-Noels, A., Guenther, E., Haswell, C. A., Hatzes, A. P., Hebrard, G., Hekker, S., Helled, R., Heng, K., Jenkins, J. M., Johansen, A., Khodachenko, M. L., Kislyakova, K. G., Kley, W., Kolb, U., Krivova, N., Kupka, F., Lammer, H., Lanza, A. F., Lebreton, Y., Magrin, D., Marcos-Arenal, P., Marrese, P. M., Marques, J. P., Martins, J., Mathis, S., Mathur, S., Messina, S., Miglio, A., Montalban, J., Montalto, M., Monteiro, M. J. P. F. G., Moradi, H., Moravveji, E., Mordasini, C., Morel, T., Mortier, A., Nascimbeni, V., Nelson, R. P., Nielsen, M. B., Noack, L., Norton, A. J., Ofir, A., Oshagh, M., Ouazzani, R. -M, Papics, P., Parro, V. C., Petit, P., Plez, B., Poretti, E., Quirrenbach, A., Ragazzoni, R., Raimondo, G., Rainer, M., Reese, D. R., Redmer, R., Reffert, S., Rojas-Ayala, B., Roxburgh, I. W., Salmon, S., Santerne, A., Schneider, J., Schou, J., Schuh, S., Schunker, H., Silva-Valio, A., Silvotti, R., Skillen, I., Snellen, I., Sohl, F., Sousa, S. G., Sozzetti, A., Stello, D., Strassmeier, K. G., Svanda, M., Szabo, Gy. M., Tkachenko, A., Valencia, D., Van Grootel, V., Vauclair, S. D., Ventura, P., Wagner, F. W., Walton, N. A., Weingrill, J., Werner, S. C., Wheatley, P. J., Zwintz, K., Rauer, H., Catala, C., Aerts, C., Appourchaux, T., Benz, W., Brandeker, Aexis, Christensen-Dalsgaard, J., Deleuil, M., Gizon, L., Goupil, M. -J, Guedel, M., Janot-Pacheco, E., Mas-Hesse, M., Pagano, I., Piotto, G., Pollacco, D., Santos, N. C., Smith, A., Suarez, J. -C, Szabo, R., Udry, S., Adibekyan, V., Alibert, Y., Almenara, J. -M, Maro-Seoane, P. A., Ammler-von Eiff, M., Asplund, M., Antonello, E., Barnes, S., Baudin, F., Belkacem, K., Bergemann, M., Bihain, G., Birch, A. C., Bonfils, X., Boisse, I., Bonomo, A. S., Borsa, F., Brandao, I. M., Brocato, E., Brun, S., Burleigh, M., Burston, R., Cabrera, J., Cassisi, S., Chaplin, W., Charpinet, S., Chiappini, C., Church, R. P., Csizmadia, Sz., Cunha, M., Damasso, M., Davies, M. B., Deeg, H. J., Diaz, R. F., Dreizler, S., Dreyer, C., Eggenberger, P., Ehrenreich, D., Eigmueller, P., Erikson, A., Farmer, R., Feltzing, S., de Oliveira Fialho, F., Figueira, P., Forveille, T., Fridlund, M., Garcia, R. A., Giommi, P., Giuffrida, G., Godolt, M., Gomes da Silva, J., Granzer, T., Grenfell, J. L., Grotsch-Noels, A., Guenther, E., Haswell, C. A., Hatzes, A. P., Hebrard, G., Hekker, S., Helled, R., Heng, K., Jenkins, J. M., Johansen, A., Khodachenko, M. L., Kislyakova, K. G., Kley, W., Kolb, U., Krivova, N., Kupka, F., Lammer, H., Lanza, A. F., Lebreton, Y., Magrin, D., Marcos-Arenal, P., Marrese, P. M., Marques, J. P., Martins, J., Mathis, S., Mathur, S., Messina, S., Miglio, A., Montalban, J., Montalto, M., Monteiro, M. J. P. F. G., Moradi, H., Moravveji, E., Mordasini, C., Morel, T., Mortier, A., Nascimbeni, V., Nelson, R. P., Nielsen, M. B., Noack, L., Norton, A. J., Ofir, A., Oshagh, M., Ouazzani, R. -M, Papics, P., Parro, V. C., Petit, P., Plez, B., Poretti, E., Quirrenbach, A., Ragazzoni, R., Raimondo, G., Rainer, M., Reese, D. R., Redmer, R., Reffert, S., Rojas-Ayala, B., Roxburgh, I. W., Salmon, S., Santerne, A., Schneider, J., Schou, J., Schuh, S., Schunker, H., Silva-Valio, A., Silvotti, R., Skillen, I., Snellen, I., Sohl, F., Sousa, S. G., Sozzetti, A., Stello, D., Strassmeier, K. G., Svanda, M., Szabo, Gy. M., Tkachenko, A., Valencia, D., Van Grootel, V., Vauclair, S. D., Ventura, P., Wagner, F. W., Walton, N. A., Weingrill, J., Werner, S. C., Wheatley, P. J., and Zwintz, K.

Abstract

PLATO 2.0 has recently been selected for ESA's M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses fundamental questions such as: How do planetary systems form and evolve? Are there other systems with planets like ours, including potentially habitable planets? The PLATO 2.0 instrument consists of 34 small aperture telescopes (32 with 25 s readout cadence and 2 with 2.5 s cadence) providing a wide field-of-view (2232 deg(2)) and a large photometric magnitude range (4-16 mag). It focuses on bright (4-11 mag) stars in wide fields to detect and characterize planets down to Earth-size by photometric transits, whose masses can then be determined by ground-based radial-velocity follow-up measurements. Asteroseismology will be performed for these bright stars to obtain highly accurate stellar parameters, including masses and ages. The combination of bright targets and asteroseismology results in high accuracy for the bulk planet parameters: 2 %, 4-10 % and 10 % for planet radii, masses and ages, respectively. The planned baseline observing strategy includes two long pointings (2-3 years) to detect and bulk characterize planets reaching into the habitable zone (HZ) of solar-like stars and an additional step-and-stare phase to cover in total about 50 % of the sky. PLATO 2.0 will observe up to 1,000,000 stars and detect and characterize hundreds of small planets, and thousands of planets in the Neptune to gas giant regime out to the HZ. It will therefore provide the first large-scale catalogue of bulk characterized planets with accurate radii, masses, mean densities and ages. This catalogue will include terrestrial planets at intermediate orbital distances, where surface temperatures are moderate. Coverage of this parameter range with statistical numbers of bulk characterized planets is unique to PLATO 2.0. The PLATO 2.0 catalogue allows us to e. g.: - complete our knowledge of planet di, AuthorCount:160

Published
2014
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121. The PLATO 2.0 mission

Author

Rauer, H., primary, Catala, C., additional, Aerts, C., additional, Appourchaux, T., additional, Benz, W., additional, Brandeker, A., additional, Christensen-Dalsgaard, J., additional, Deleuil, M., additional, Gizon, L., additional, Goupil, M.-J., additional, Güdel, M., additional, Janot-Pacheco, E., additional, Mas-Hesse, M., additional, Pagano, I., additional, Piotto, G., additional, Pollacco, D., additional, Santos, Ċ., additional, Smith, A., additional, Suárez, J.-C., additional, Szabó, R., additional, Udry, S., additional, Adibekyan, V., additional, Alibert, Y., additional, Almenara, J.-M., additional, Amaro-Seoane, P., additional, Eiff, M. Ammler-von, additional, Asplund, M., additional, Antonello, E., additional, Barnes, S., additional, Baudin, F., additional, Belkacem, K., additional, Bergemann, M., additional, Bihain, G., additional, Birch, A. C., additional, Bonfils, X., additional, Boisse, I., additional, Bonomo, A. S., additional, Borsa, F., additional, Brandão, I. M., additional, Brocato, E., additional, Brun, S., additional, Burleigh, M., additional, Burston, R., additional, Cabrera, J., additional, Cassisi, S., additional, Chaplin, W., additional, Charpinet, S., additional, Chiappini, C., additional, Church, R. P., additional, Csizmadia, Sz., additional, Cunha, M., additional, Damasso, M., additional, Davies, M. B., additional, Deeg, H. J., additional, Díaz, R. F., additional, Dreizler, S., additional, Dreyer, C., additional, Eggenberger, P., additional, Ehrenreich, D., additional, Eigmüller, P., additional, Erikson, A., additional, Farmer, R., additional, Feltzing, S., additional, Oliveira Fialho, F. de, additional, Figueira, P., additional, Forveille, T., additional, Fridlund, M., additional, García, R. A., additional, Giommi, P., additional, Giuffrida, G., additional, Godolt, M., additional, da Silva, J. Gomes, additional, Granzer, T., additional, Grenfell, J. L., additional, Grotsch-Noels, A., additional, Günther, E., additional, Haswell, C. A., additional, Hatzes, A. P., additional, Hébrard, G., additional, Hekker, S., additional, Helled, R., additional, Heng, K., additional, Jenkins, J. M., additional, Johansen, A., additional, Khodachenko, M. L., additional, Kislyakova, K. G., additional, Kley, W., additional, Kolb, U., additional, Krivova, N., additional, Kupka, F., additional, Lammer, H., additional, Lanza, A. F., additional, Lebreton, Y., additional, Magrin, D., additional, Marcos-Arenal, P., additional, Marrese, P. M., additional, Marques, J. P., additional, Martins, J., additional, Mathis, S., additional, Mathur, S., additional, Messina, S., additional, Miglio, A., additional, Montalban, J., additional, Montalto, M., additional, P. F. G. Monteiro, M. J., additional, Moradi, H., additional, Moravveji, E., additional, Mordasini, C., additional, Morel, T., additional, Mortier, A., additional, Nascimbeni, V., additional, Nelson, R. P., additional, Nielsen, M. B., additional, Noack, L., additional, Norton, A. J., additional, Ofir, A., additional, Oshagh, M., additional, Ouazzani, R.-M., additional, Pápics, P., additional, Parro, V. C., additional, Petit, P., additional, Plez, B., additional, Poretti, E., additional, Quirrenbach, A., additional, Ragazzoni, R., additional, Raimondo, G., additional, Rainer, M., additional, Reese, D. R., additional, Redmer, R., additional, Reffert, S., additional, Rojas-Ayala, B., additional, Roxburgh, I. W., additional, Salmon, S., additional, Santerne, A., additional, Schneider, J., additional, Schou, J., additional, Schuh, S., additional, Schunker, H., additional, Silva-Valio, A., additional, Silvotti, R., additional, Skillen, I., additional, Snellen, I., additional, Sohl, F., additional, Sousa, S. G., additional, Sozzetti, A., additional, Stello, D., additional, Strassmeier, K. G., additional, Švanda, M., additional, Szabó, Gy. M., additional, Tkachenko, A., additional, Valencia, D., additional, Van Grootel, V., additional, Vauclair, S. D., additional, Ventura, P., additional, Wagner, F. W., additional, Walton, N. A., additional, Weingrill, J., additional, Werner, S. C., additional, Wheatley, P. J., additional, and Zwintz, K., additional

Published
2014
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123. Exoplanet Magnetic Field Estimation via Energetic Neutral Atoms (ENAs) and Hydrogen Cloud Observations and Modelling. Planetary Radio Emissions| PLANETARY RADIO EMISSIONS VII 7

Author

Hanslmeier, A., Selsis, F., Lammer, H., Grießmeier, J.-M., Kislyakova, K. G., Khodachenko, M. L., Holmström, M., Wurz, P., Hanslmeier, A., Selsis, F., Lammer, H., Grießmeier, J.-M., Kislyakova, K. G., Khodachenko, M. L., Holmström, M., and Wurz, P.

Abstract

The discovery of more than 500 exoplanets during the past 15 years has enabled us to characterize the upper atmosphere structure of some exosolar gas giants and to compare observational and modelling results to the known planets in the Solar System. It is of great interest to understand if these exosolar “Hot Jupiters” share similar physical processes compared to the giant planets (Jupiter and Saturn) in the Solar System with regard to their magnetic dynamos and the corresponding expected magnetic field strengths. In this work we discuss how observations of stellar Lyman-a absorption by so-called Energetic Neutral Atoms (ENAs) around transiting exoplanets together with theoretical modelling efforts can be used as a tool for estimating magnetic obstacle sizes and the corresponding magnetic field strength. For demonstrating this method we model the production of stellar wind related planetary hydrogen and ENA populations around the exosolar gas giant HD 209458b and show how a detailed analysis of attenuation spectra obtained during transits can be used for the estimation of the planet’s magnetic obstacle size and hence its dynamo field strength. Our study indicates that the magnetic field strength of HD 209458b which is able to balance the stellar wind plasma flow by a magnetic obstacle around the planet which can explain the observed Lyman-a line profiles observed before and during the transits by HST corresponds to a magnetic dipole moment which is ~40 % of Jupiters value.

Published
2011

124. Solar Wind and Saturnian Moons Signatures in the Long-Periodic Modulations of SKR (abstract). Planetary Radio Emissions| PLANETARY RADIO EMISSIONS VII 7

Author

Kislyakov, A. G., Rucker, H. O., Kislyakova, K. G., Khodachenko, M. L., Panchenko, M., Taubenschuss, U., Kislyakov, A. G., Rucker, H. O., Kislyakova, K. G., Khodachenko, M. L., Panchenko, M., and Taubenschuss, U.

Abstract

Long-periodic (LP) modulations of intensity of Saturnian Kilometric Radiation (SKR) recorded by RPWS instrument onboard Cassini spacecraft were studied by means of a combined data analysis algorithm based on a ”sliding window” Fourier (SWF) procedure and the nonlinearWigner-Ville (WV) method. The analyzed SKR data record covers the years 2004-2005. It has been found that SKR has well pronounced impulsive modulation, with quasi-periodic pulses appeared approximately each 10.74 hours and having duration of about 5 hours. The period of pulses, in spite of the overall stability, has sometimes the disturbances within the interval of 10.74 - 10.76 hours. By this, the whole impulsive modulation of SKR appeared in 2004-2005 in a form of quasi-regularly repeated modulation activity storms. Time interval between the adjacent modulation activity storms most often was within 8-13 days. Altogether, 55 impulsive modulation activity storms were registered during 2004-2005. Besides of the storms of 10.7 h pulses, the intensity of SKR has several more long periodic modulations. In particular, ~6-7 days, ~8-9 days, ~12-13 days and ~25-27 days components were detected. These are connected probably with the quasi-regular character of the storms of 10.74 h pulses. While the origin of 10.74 hour pulses can be associated with the rotation of Saturn, the long periodic modulation features are very likely connected with the detected similar variations of the solar wind parameters. The last in their turn may be caused by the varying solar surface magnetic activity and rotating streams of high speed solar wind. Besides of that, the performed analysis shows that some Saturnian moons may also have influence on the intensity of SKR. In particular, specific modulations with periods corresponding to orbital motions of close moons (Enceladus, Tethys) as well as Titan, Hyperion and Dione were detected.

Published
2011

125. Long-Periodic Transverse Oscillations of Coronal Loops and Modulations of Solar Microwave Radiation. Planetary Radio Emissions| PLANETARY RADIO EMISSIONS VII 7

Author

Kislyakov, A. G., Rucker, H. O., Koslyakova, K. G., Khodachenko, M. L., Panchenko, M., Arkhypov, O. V., Zaqarashvili, T. V., Zaitsev, V. V., Kislyakov, A. G., Rucker, H. O., Koslyakova, K. G., Khodachenko, M. L., Panchenko, M., Arkhypov, O. V., Zaqarashvili, T. V., and Zaitsev, V. V.

Abstract

The paper deals with interpretation of long-periodic (minutes, e.g. < 0.01 Hz) modulations, detected in the microwave records during flaring events on the Sun, as the signatures of large scale transverse oscillations of coronal loops, observed at the same time by TRACE. In the case of transverse large scale oscillatory motions of a loop a properly located observer, besides of the modulation caused by motion of the emission diagram pattern at the main oscillation frequency, may see also a modulation at double frequency of the loop oscillation, resulted by a varying magnetic field during each inclination of the loop, as well as weaker higher harmonics. Identification of such ”modulation pairs” in the dynamic spectra of solar microwave emission and their association with the observed oscillating coronal loops form the major result of the undertaken investigation. Three different events with the detected by TRACE post-flare oscillating loops were considered in that study (Mar.23,2000; Sep.15,2001; Sep.07,2001).

Published
2011

126. Millimeter Radio Astronomy and the Solar Convection Zone. Planetary Radio Emissions| PLANETARY RADIO EMISSIONS VII 7

Author

Khodachenko, M. L., Antonov, O. V., Arkhypov, O. V., Khodachenko, M. L., Antonov, O. V., and Arkhypov, O. V.

Abstract

The global distribution of solar surface activity (active regions) is connected with processes in the convection zone. To extract the information on large-scale motions in the convection zone, we study the solar synoptic charts (Mount Wilson 1998-2004, Fe I, 525.02 nm). The clear indication of large-scale (= 18°) turbulence is found. This may be a manifestations of the deep convection because there is no such global turbulent eddies in the solar photosphere. The preferred scales of longitudinal variations in surface solar activity are revealed. These correspond to ~ 15° to 51° (gigantic convection cells), 90°, 180° and 360°. Similar scales (e.g., 40° and 90°) are found in the millimeter radio-images (Mets¨ahovi Radio Observatory 1994-1998, 37 and 87 GHz). Hence, the millimeter radio astronomy could prove useful for remote sensing of the solar convection zone.

Published
2011

127. Magnetohydrodynamic Shocks and Solitons in the Solar Atmosphere: Recent Challenges in Observations and Theory. Planetary Radio Emissions| PLANETARY RADIO EMISSIONS VII 7

Author

Rucker, H. O., Murawski, K., Khodachenko, M. L., Zaqarashvili, T. V., Kukhianidze, V., Rucker, H. O., Murawski, K., Khodachenko, M. L., Zaqarashvili, T. V., and Kukhianidze, V.

Abstract

Magnetohydrodynamic shocks are believed to play a significant role in the dynamics of lower solar atmosphere. Here we review the recent theoretical developments in shock wave induced phenomena and first observational evidence of slow sausage soliton in the solar chromosphere.

Published
2011

136. Stellar Wind and the Efficiency of Plasma Radio Emission from Exoplanets.

Author

Zaitsev, V. V., Shaposhnikov, V. E., Khodachenko, M. L., and Rumenskikh, M. S.

Subjects
*STELLAR winds, *STELLAR activity, *EXTRASOLAR planets, *PLASMA production, *PLASMA waves, *PLASMA frequencies, *SOLAR wind
Abstract

We present the results of our study of the influence of stellar activity on the efficiency of the plasma radio emission generation mechanism and the properties of this emission in the atmospheres of exoplanets with a weak magnetic field. The plasma generation mechanism can be efficiently realized in the case where the Langmuir frequency exceeds the electron gyrofrequency, and the electron cyclotron maser is inefficient. This mechanism, which depends significantly on plasma parameters, suggests the generation of plasma (quasi-static) waves by energetic electrons followed by their conversion into electromagnetic radiation. The stellar wind, depending on its intensity, can modify significantly the plasmasphere of an exoplanet and change its parameters. Using the interaction of the exoplanet HD 189733b with a stellar wind of various intensities from the central star as an example, we show that the plasma mechanism can be realized at any stellar wind intensity, only the requirements for the parameters of the plasma mechanism change. In particular, the plasma wave energy density needed to generate a radio flux accessible to detection by modern radio-astronomical means changes, and its frequency range changes. The latter will allow the detected radio emission to be used as an indicator of the activity of the parent star. [ABSTRACT FROM AUTHOR]

Published
2024
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140. Solar flares as proxy for the young Sun: satellite observed thermosphere response to an X17.2 flare of Earth's upper atmosphere

Author

Krauss, S., primary, Fichtinger, B., additional, Lammer, H., additional, Hausleitner, W., additional, Kulikov, Yu. N., additional, Ribas, I., additional, Shematovich, V. I., additional, Bisikalo, D., additional, Lichtenegger, H. I. M., additional, Zaqarashvili, T. V., additional, Khodachenko, M. L., additional, and Hanslmeier, A., additional

Published
2012
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