Influence of ultraviolet radiations of astrophysical origin on Earth's biosphere

• Grant number: 09/09969-9
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• Start date: July 15, 2010
• End date: September 14, 2010
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Stellar Astrophysics
• Principal Investigator: Jorge Ernesto Horvath
• Grantee: Jorge Ernesto Horvath
• Visiting researcher: Rolando Pedro Cardenas Ortiz
• Visiting researcher institution: Universidad Central Marta Abreu de Las Villas (UCLV), Cuba
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The visiting researcher will first conclude a study of the effects of ultraviolet radiations reaching Earth's biosphere, as a consequence of the impact of a Gamma Ray Burst, with focus on subsurface aquatic biota. This is very important, as most studies so far have only examined the effects of ionizing radiation (coming from astrophysical sources) considering the species which live on the surface of the oceans and land environments. Later the visiting researcher will begin the study of the potential effects of "superburst" from a Soft Gamma Repeater (SGR) close enough to the Earth would cause on surface biota, using the formalism of biological effective fluxes and fluences. A similar study for Gamma Ray Bursts has been recently published as a result of our collaboration with the visiting researcher and with his PhD student Osmel Martin. In the future the study would be extended to subsurface biota, possibly exploring second-order population dynamics. (AU)