Makes elements heavier than iron abundance of elements neutron capture processes big bang nucleosynthesis makes only isotopes with atomic masses 2, 3, 4 and 7. Iron is said to have the greatest nuclear binding energy of any element, more energy per particle is required to break up an iron-56 nucleus than the nucleus of any other element all other elements are too weak, unsupportive, etc for them to last long, they will become supernova. The lightest elements (hydrogen, helium, deuterium, lithium) were produced in the big bang nucleosynthesis according to the big bang theory, the temperatures in the early universe were so high that fusion reactions could take place. Massive red giants are also able to make small amounts of elements heavier than iron (up to mercury and lead) through a slower combination of neutrons with heavy nuclei, but supernova probably generate the majority of elements heavier than iron and nickel (and certainly those heavier than lead up to uranium. All of the elements heavier than iron would have had to have come from stellar nucleosynthesis (specifically, via neutron capture, proton capture, or photo-disintegration), as big bang nucleosynthesis couldn't make anything heavier the beryllium.
Stellar nucleosynthesis is the process by which elements are created within stars by combining the protons and neutrons together from the nuclei of lighter elements all of the atoms in the universe began as hydrogen fusion inside stars transforms hydrogen into helium, heat, and radiation heavier. Elements heavier than iron and some isotopes of lighter elements may be accounted for by capture of successive neutrons the capture of a neutron increases the mass of a nucleus subsequent radioactive beta decay converts a neutron into a proton (with ejection of an electron and an antineutrino), leaving the mass practically unchanged. A star's energy comes from the combining of light elements into heavier elements in a process known as fusion, or nuclear burningit is generally believed that most of the elements in the universe heavier than helium are created, or synthesized, in stars when lighter nuclei fuse to make heavier nuclei.
Stellar nucleosynthesis is the process by which the natural abundances of the chemical elements within stars vary due to nuclear fusion reactions in the cores and overlying mantles of stars. The elements heavier than iron, which have been detected in the ancient stars of the galactic halo, in the ism, dust grains, meteorites, and on earth, are formed by neutron-capture reactions. Fusion of elements with mass numbers (the number of protons and neutrons) greater than 26 uses up more energy than is produced by the reaction thus, elements heavier than iron cannot be fuel sources in stars. Big bang nucleosynthesis produced no elements heavier than lithium to do that you need stars, which means waiting around for at least 200 billion years we are all made of stars. Elements heavier than lithium are all synthesized in stars during the late stages of stellar evolution , massive stars burn helium to carbon, oxygen, silicon, sulfur, and iron elements heavier than iron are produced in two ways: in the outer envelopes of super-giant stars and in the explosion of a supernovae.
The construction of elements heavier than fe (iron) involves nucleosynthesis by neutron capture a nuclei can capture or fuse with a neutron because the neutron is electrically neutral and, therefore, not repulsed like the proton. Nucleosynthesis is the process by which elements heavier than hydrogen are created elements lighter than iron release energy if additional nucleons are added to their nuclei nucleons are protons and neutrons.
All of the elements on earth heavier than helium were produced in stellar furnaces, the chemical elements up to the iron peak are produced in ordinary stellar nucleosynthesis many elements heavier than iron are formed supernova explosions the amount of energy released during a supernova explosion. Fusion of heavier elements than iron, as is the case for gold, however, does no liberate energy further, massive stars burn much faster than sun-like stars, because their energy consumption is so much higher. Further nucleosynthesis processes can occur, in particular the r-process (rapid process) described by the b 2 fh paper and first calculated by seeger, fowler and clayton, in which the most neutron-rich isotopes of elements heavier than nickel are produced by rapid absorption of free neutrons.
Stellar nucleosynthesis is the theory explaining the creation except in the understanding of nucleosynthesis of those elements heavier than iron by neutron capture. Photodisintegration is endothermic (energy absorbing) for atomic nuclei lighter than iron and sometimes exothermic (energy releasing) for atomic nuclei heavier than iron photodisintegration is responsible for the nucleosynthesis of at least some heavy, proton-rich elements via the p-process in supernovae.