Polarized Radiation And The Emergence Of Biological Homochirality On Earth And Beyond

Underground fluxes of muons and electrons on Earth (top) and on an icy moon without an atmosphere (bottom). The spectrum and composition of the primary cosmic rays are the one observed at Earth at the present epoch. In the left panels, the total µ + + µ − spectra at different depths are figured by the solid lines; the polarized muons by dashed lines. The fraction of polarized muons is close to unity since they mostly come from pion decay. In the right panels, the total e + + e − spectra, i.e. those produced by all lepto-hadronic processes and also from bremsstrahlung pairs, are shown by solid lines at different depths. The polarized e + + e − from decay of muons are shown by dashed lines.

It has been proposed that spin-polarized cosmic radiation can induce asymmetric changes in helical biopolymers that may account for the emergence of biological homochirality. The parity violation in the weak interaction has direct consequences on the transport of polarization in cosmic ray showers.

In this paper, we show that muons retain their polarization down to energies at which they can initiate enantioselective mutagenesis. Therefore, muons are most likely to succeed in establishing the connection between broken symmetries in the standard model of particle physics and that found in living organisms.

We calculate the radiation doses deposited by primary and secondary cosmic rays at various prime targets for the searches of life in the solar system: Mars, Venus, Titan, icy moons and planetesimals, and discuss the implications for the enantioselective mutagenesis proposed as to be the driver of homochiralization. Earth is unusual in that spin-polarized muons dominate the cosmic radiation at its surface.

Noemie Globus, Anatoli Fedynitch, Roger D. Blandford
Comments: 10 pages, 5 figures, submitted to the Astrophysical Journal
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); High Energy Astrophysical Phenomena (astro-ph.HE)
Cite as: arXiv:2101.00530 [astro-ph.EP] (or arXiv:2101.00530v1 [astro-ph.EP] for this version)
Submission history
From: Noemie Globus
[v1] Sat, 2 Jan 2021 23:40:09 UTC (479 KB)
Astrochemistry, Astrobiology,

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