Big bang nucleosynthesis and the cosmic lithium problem. Ryan centre for astrophysics research and department of physics, astronomy and mathematics university of hertfordshire aim of this talk to describe the origin of the elements sfhilk 1 s. Big bang nucleosynthesis began roughly 10 seconds after the big bang, when the universe had cooled sufficiently to allow deuterium nuclei to survive disruption by highenergy photons. Primordial nucleosynthesis, or big bang nucleosynthesis bbn, is one of the three evidences for the big bang model, together with. Primordial nucleosynthesis, or big bang nucleosynthesis bbn, is one of the three evidences for the big bang model, together with the expansion of the universe and the cosmic microwave background. Terms in this set 30 big bang nucleosynthesis refers to. The figure shows a theoretical prediction of the abundance of different elements as a function of temperature, or time after the big bang.
The local galactic abundance distribution of nuclear species, as a function of. The important point is that the prediction depends critically on the density of baryons ie neutrons and protons at the time of nucleosynthesis. It is the testing ground upon which many cosmological models must. Big bang nucleosynthesis may be directly confronted with observational data. The history of big bang nucleosynthesis began with the calculations of ralph alpher and george gamow in the 1940s. Origin of the light elements university of california. The agreement between the predicted and observed abundances of deuterium, helium3, helium4, and lithium7 confirms the standard cosmology model and allows accurate determination of the baryon density, between 1. Among many kinds of books concerning the big bang theory, we present a book which includes a detailed description of big bang nucleosynthesis bbn whose theme has not been explained well so far. Stellar nucleosynthesis evolutionary time scales for a 15 m sun star. After the big bang, the universe started to e x p a n d. Big bang nucleosynthesis and physics beyond the standard model subir sarkar department of physics, university of oxford, 1 keble road, oxford ox1 3np, u.
The vast majority of the mass of ordinary matter in the universe is hydrogen and helium, remaining from the early stages of the universe. What elements is big bang nucleosynthesis responsible for. Hydrogenhelium abundance hydrogen and helium account for nearly all the nuclear matter in todays universe. The expansion of the universe nucleosynthesis of the light elements origin of the cosmic background radiation formation of galaxies and largescale structure. Eric lerner pdf documents download area big bang never happened. In physical cosmology, big bang nucleosynthesis or primordial nucleosynthesis refers to the production of nuclei other than h1, the normal, light hydrogen, during the early phases of the. Burbidge, burbidge, fowler and hoyle worked out the nucleosynthesis processes that go on in stars, where. Pdf primordial nucleosynthesis remains as one of the pillars of modern cosmology. The bigbangonline suite of codes is a cloud computing system that enables researchers to set up, execute, and visualize a custom big bang nucleosynthesis calculation, and compare the results to observations of the primordial light element abundances to constrain the baryon density. Results rather general, valid also for nonsusy scenarios and nonwimps.
The four key observational successes of the model are. Monte carlo simulations can also be run wherein uncertainties. If dark matter particles are discovered, scenarios leading to too large or too small relic densities should not be disregarded. Bbn is the interdisciplinary field which incorporates nuclear. We emphasize the role of key nuclear reactions and the methods by which experimental cross section. A paper, published in april 1948, named \the origin of chemical elements, was. Weak interaction freezeout primordial nucleosynthesis. Stellar nucleosynthesis has occurred since the original creation of hydrogen, helium and lithium during the big bang. If the file has been modified from its original state, some details such as the timestamp may not fully reflect those of the original file. Periodic table showing origin of elements in the solar system, based on data by jennifer johnson at ohio state university. Bigbang nucleosynthesis and the baryon density of the. Pdf introduction to big bang nucleosynthesis and modern. So it is best to download them to your desktop first and then open them from there. Implications of bbn on chemical evolution, dark matter and constraints on particle properties will be discussed.
The term nucleosynthesis refers to the formation of heavier elements, atomic nuclei with many protons and neutrons, from the fusion of lighter elements. Weak interaction freezeout at high temperature, the matter in the big bang consisted only of its most elementary constituents. The initial elemental composition in the universe was established by primordial nucleosynthesis shortly after the big bang, producing all the hydrogen and deuterium of the universe the total hydrogen mass fraction is. There is a good global agreement over a range of nine orders of magnitude between abundances of 4he, d, 3he and 7li deduced from observations. Note that the neutronproton freezeout time was earlier. Activities student worksheet learn nuclear science with marbles. Bigbang nucleosynthesis, early universe and relic particles. Stellar nucleosynthesis is the creation nucleosynthesis of chemical elements by nuclear fusion reactions within stars. The primordial abundances of the light elements synthesized during the first few.
According to current theories, the first nuclei were formed a few minutes after the big bang, through nuclear reactions in a process called big bang nucleosynthesis. An investigation of the history of matter from the big bang to the present princeton university press arnett, w. The theoretical prediction for the abundances of d, 3 he, 4 he, and 7 li is discussed. More stuff during the 1970s, there was a major puzzle in that the density of baryons as calculated by big bang nucleosynthesis was much less than the observed mass of the universe based on. Bigbang nucleosynthesis bbn offers the deepest reliable probe of the early universe, being based on wellunderstood standard model. Big bang nucleosynthesis the modeling of the early universe by the standard big bang model gives a scenario that involves twelve nuclear interactions that led to the present cosmic abundances of elements outside the stars. Big bang nucleosynthesis can help setting limits on the possible deviations. Implications of bbn on chemical evolution and constraints on particle properties will also be discussed. A paper, published in april 1948, named \the origin of. In physical cosmology, big bang nucleosynthesis abbreviated bbn, also known as primordial nucleosynthesis, archeonucleosynthesis, archonucleosynthesis, protonucleosynthesis and paleonucleosynthesis is the production of nuclei other than those of the lightest isotope of hydrogen hydrogen1, 1 h, having a single proton as a nucleus during the early phases of the universe. This is consistent with the standard or big bang model. Activities student worksheet learn nuclear science.
Refers to the production of nuclei other than those of the lightest isotope of hydrogen during the early phases of the universe. Introduction to big bang nucleosynthesis and modern cosmology article pdf available in international journal of modern physics e 265 june 2017 with 730 reads how we measure reads. The theory describing the creation of light elements in the universe is, together with the prop erties of the cmb. During primordial nucleosynthesis, several of the light elements form. The narrow vertical band indicates the cmb measure of the cosmic baryon density, while the. Big bang nucleosynthesis and the cosmic lithium problem karsten jedamzik montpellier karsten jedamzik, university of porto, cosmo11, august 24th11 p. In particular, we analyze the constraints that big bang nucleosynthesis places upon the possible time variation of fundamental constants, along with constraints on the nature and origin of dark matter and dark energy, longlived supersymmetric particles, gravity. The big bang nucleosynthesis theory predicts that roughly 25% the mass of the universe consists of helium. Theory of big bang nucleosynthesis the relative abundances of the lightest elements hydrogen, deuterium, helium3 and helium4, and some lithium and beryllium provide a strong test of the hypothesis that the universe was once far hotter and denser than it is now. If the standard model secondaries induced by the decays of these particles have not been thermalized by the background cosmic plasma before the start of big bang nucleosynthesis bbn, the decay showers may alter the primordial abundances of the light elements through.
This file contains additional information such as exif metadata which may have been added by the digital camera, scanner, or software program used to create or digitize it. The big bang theory predicts that the early universe was a very hot place. Big bang nucleosynthesis and neutrinos 3 where m 1. To download right click on the link and save target as if you only click on the link then the browser will try to open the pdf file and some of them are big and will take a long time to open. Free neutrons are unstable with a halflife of about ten minutes 614. We present an overview of the standard model of big bang nucleosynthesis bbn, which describes the production of the light elements in the early universe. By the first millisecond, the universe had cooled to a few trillion kelvins 10 12 k and quarks finally had the opportunity to bind together into free protons and neutrons. Bbn is the interdisciplinary field which incorporates nuclear physics, elementary particle physics, and astronomy. Big bang nucleosynthesis and physics beyond the standard model. In physical cosmology, big bang nucleosynthesis is the production of nuclei other than those of the lightest isotope of hydrogen hydrogen1, 1h, having a single. Three pillars of the big bang including bbn stellar.
Nucleosynthesis nasas cosmicopia, big bang nucleosynthesis martin white, university of california, berkeley, and stellar nucleosynthesis ohio. In physical cosmology, big bang nucleosynthesis abbreviated bbn, also known as primordial nucleosynthesis refers to the production of nuclei other than those of the lightest isotope of hydrogen hydrogen1, 1 h, having a single proton as a nucleus during the early phases of the universe. When the temperature dropped below a few hundred mev, ordinary nucleons or baryons could. Many extensions of the standard model of particle physics predict the existence of massive unstable or metastable particles. As a predictive theory, it yields accurate estimates of the observed abundances of the elements. Jan 22, 2010 here are a few links that might interest you. Boxes indicate the observed light element abundances. Big bang nucleosynthesis the emergence of elements in the universe benjamin topper abstract.
Big bang nucleosynthesis gamow, alpher and herman proposed the hot big bang as a means to produce all of the elements. Big bang nucleosynthesis from the expansion of the early universe and the cosmic microwave background cmb, we know the initial universe was cool enough to form nuclei but hot enough to have nuclear reactions from the first several seconds to the first several minutes starting with neutrons and protons, the resulting reaction. For almost 30 years, the predictions of big bang nucleosynthesis have been used to test the big bang model to within a fraction of a second of the bang. Explanation of element formation through big bang nucleosynthesis, stellar nucleosynthesis, and supernovae nucleosynthesis. What we have seen is that a theoretical model based on the assumption that there was a big bang, and incorporating an assumption about the presentday value of the baryonic density. However, the lack of stable nuclei with atomic weights of 5 or 8 limited the big bang to producing hydrogen and helium.
We now understand the order in our world by using the standard hot big bang model of the evolution of the universe. The primordial abundances of 4he, d, 3he, and 7li as predicted by the standard model of bigbang nucleosynthesis the bands show the 95% cl range 5. Big bang nucleosynthesis department of physics, iit madras. The light elements nucleosynthesis in the early universe. The process of forming the hydrogen and helium and other trace constituents is often called big bang nucleosynthesis. In pdf format most of the images in this web paper. Nuclear reactions taking place in the moments after the big bang produced. The primordial abundances of 4he, d, 3he, and 7li as predicted by the standard model of bigbang nucleosynthesisthe bands show the 95% cl range 5. Big bang nucleosynthesis with a nonmaxwellian distribution. Big bang nucleosynthesis, often abbreviated bbn, refers to the network of nuclear reactions governing the formation of light elements, most signi.
The percentages of each elements origin are represented by squares out of a hundred to make it easier to estimate proportions. A few minutes into the expansion, when the temperature was about a billion kelvin and the density of matter in the universe was comparable to the current density of earths atmosphere, neutrons combined with protons to form the universes deuterium and helium nuclei in a process called big bang nucleosynthesis bbn. Big bang nucleosynthesis also known as primordial nucleosynthesis describes the production of nuclei, heavier than the lightest isotope of hydrogen 1h with a single proton as a nucleus, in the early phases of the universe 1. Primordial nucleosynthesis is one of the three historical evidences for the big bang model, together with the expansion of the universe and the cosmic. The local galactic abundance distribution of nuclear species, as a function of mass number a. Mev and can impose strong limits on this kind of models, since it may be a ected by the presence of a dark densit. A brief account of big bang nucleosynthesis can be found in the spotlight text big bang nucleosynthesis, while equilibrium and change provides more information about the physical processes involved and elements of the past describes how the predictions of big bang nucleosynthesis can be tested against astronomical observation. The narrow vertical band indicates the cmb measure of the cosmic baryon density, while the wider.
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