INVESTIGADORES
VILLARREAL D'ANGELO Carolina Susana
congresos y reuniones científicas
Título:
On the sensitivity of extrasolar mass-loss rate ranges: HD 209458b a case study
Autor/es:
VILLARREAL D'ANGELO, CAROLINA; SCHNEITER, MATIAS; COSTA, ANDREA; VELAZQUEZ, PABLO; RAGA, ALEJANDRO; ESQUIVEL, ALEJANDRO
Reunión:
Conferencia; 57 Reunión Anual de la Asociación Argentina de Astronomía; 2014
Resumen:
<!-- /* Font Definitions */@font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1073786111 1 0 415 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin:0in;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:Calibri;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-fareast-language:EN-US;}@page WordSection1{size:8.5in 11.0in;margin:70.85pt 70.85pt 70.85pt 70.85pt;mso-header-margin:.5in;mso-footer-margin:.5in;mso-paper-source:0;}div.WordSection1{page:WordSection1;}-->We present a 3D hydrodynamic study of the effects thatdifferent stellar wind conditions and planetary wind structures have on thecalculated Ly-alpha absorptions produced by a cometary tail during transit. Weconcentrate, as a case study, on the known HD 209458b case. Initially, weassume a broad range of possible planetary mass loss rate values ([1-7]x10^10g/s). Then, by comparing the observational Ly-alpha absorption with thenumerically derived ones, we could constrain these values within the givenrange. We find that the planetary mass-loss rate does not change dramaticallyfor large changes in stellar wind speeds [250-800] km/s and temperature [3-7]MKwhile keeping fixed the stellar mass-loss rate. The planetary mass loss raterange found is [3-5]x10^10 g/s, depending upon the efficiency of the stellarwind to transport heat (polytropic index between [1.01-1.13]), leading todifferent stellar wind speeds. Several models with anisotropic evaporationprofiles for the planetary escaping atmosphere were carried out, showing thatboth, the escape through polar regions, resembling the emission associated withreconnection processes, and through the night side, produced by a strongstellar wind that compresses the planetary atmosphere and inhibits its escapefrom the day hemisphere yields larger absorptions than an isotropic planetarywind.