Answer:
Elements heavier than iron are formed by neutron capture processes during stellar death and supernovae.
Step-by-step explanation:
Most of the elements heavier than iron are formed during the death of stars through neutron capture processes, specifically the R-Process and the S-Process. The R-Process is a rapid capture of neutrons, while the S-Process is a slow capture of neutrons. These processes either directly form elements or indirectly form them through decay processes [^1]. Elements heavier than iron are primarily made in environments with free-neutron densities in excess of a million particles per cubic centimeter [^2]. In the extreme energetic conditions of supernovae, atoms are bombarded by a very large number of neutrons, and rapid successive neutron capture, followed by beta decay, produces the heavier atoms [^5].
So, elements heavier than iron are formed by neutron capture processes during stellar death and supernovae.
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