Title: Mapping Galactic 60Fe synthesis in Centaurus-Circinus

Title: Mapping Galactic 60Fe synthesis in Centaurus-Circinus

Proposal ID: 0120158
Subject category: Nucleosynthesis
Principal investigator: Hartmann
Institute: Clemson University

Abstract

We propose a 2000 ks SPI observation of the Centaurus-Circinus region, centered on (l,b) = (310,0), with the goal of detecting the gamma-ray lines from 60Fe. We also request SPI data from other open time exposures this region, if these observations do not address the gamma-ray lines from 60Fe. 60Fe is coproduced with 26Al in supernovae of Type II. However, 60Fe is only produced in SNII while 26Al has many potential synthesis sources. Existing 60Fe flux limits are close to theoretical predictions, so that a detection with INTEGRAL is imminent. Detecting, and perhaps even mapping, of 60Fe would provide crucial information on the role SNII play for the synthesis of 26Al, and it would constrain theoretical nucleosynthesis calculations. The proposed Cen-Cir observation complement the deep inner galaxy exposure and the Cygnus/Vela pointings planned in the Core Program. The combination of all data after completion of the INTEGRAL mission life will advance astronomy with radioactivities through the use of 26Al and 60Fe as powerful tracers of galactic chemical evolution.