• Study Resource
  • Explore
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
NUCLEOSYNTHESIS
NUCLEOSYNTHESIS

... → destroyed in CNO-cycle exotic speculations about origin • explosive H-burning in novae? • neutrino-induced nucleosynthesis in supernovae? 16 O (ν,n) 15 O (β + ) 15 N ...
Stages 12 to 14
Stages 12 to 14

... The inner core continues to contract an heat up, moving to the left on the HR Diagram. The intense radiation pressure from the core pushes the shell away from the central core. The central core will collapse until it is supported once again by electron degeneracy pressure. ...
Learning Targets
Learning Targets

... 1. I am able to state the characteristics used for classifying stars. 2. I know how to describe what a light-year is. 3. I know how to use a Hertzsprung-Russell diagram to classify stars. 15.3 Lives of Stars 4. I am able to state the life cycle of small and large stars. 15.4 Star Systems and Galaxie ...
Unit 1 The Universe
Unit 1 The Universe

... cause two or more low-mass atomic nuclei to form a heavier nucleus. Gives off light. • Occurs for most of the stars life. ...
From galaxies to stars
From galaxies to stars

... Ages of stars: from http://www.universetoday.com/83315/thick-stellar-disk-isolated-in-andromeda/ Astronomer’s periodic table: Ben McCall http://bjm.scs.uiuc.edu/pubs/BJMpres25.pdf Formation of the Milky Way: from “The formation and evolution of the Milky Way” by Cristina Chiappini, American Scientis ...
Introduction to Fission and Fusion
Introduction to Fission and Fusion

... In this example, a stray neutron strikes an atom of U-235. It absorbs the neutron and becomes an unstable atom of U-236. It then undergoes fission. Notice that more neutrons are released in the reaction. These neutrons can strike other U-235 atoms to initiate their fission. ...
Astronomy 100 Tuesday, Thursday 2:30
Astronomy 100 Tuesday, Thursday 2:30

... • Will end up as a White Dwarf ...
The Life of the Universe - University of Minnesota
The Life of the Universe - University of Minnesota

... forces became unique • Energy of photons high enough to create matter and vice versa ...
It all began with a Big Bang!
It all began with a Big Bang!

... cannot travel through a vacuum. 'Outer space' begins about 200 km above the Earth. Space appears as a black blanket dotted with stars. Space is not empty, the openings between the stars and planets are filled with huge amounts of gas and dust. ...
nuclear physics nuclear physics
nuclear physics nuclear physics

... atoms are compressed so as to give precedence to the strong interaction on the electromagnetic repulsion, joining together and thus going to generate a core of greater mass of the nuclei reagents and, sometimes, one or more free neutrons, the fusion of elements up to atomic numbers 26 and 28 (iron a ...
Taking fingerprints of stars
Taking fingerprints of stars

... Taking the fingerprints of stars, galaxies, and interstellar gas clouds Absorption and emission from atoms, ions, and molecules ...
ASTR 1120H – Spring Semester 2010 Exam 2 – Answers The
ASTR 1120H – Spring Semester 2010 Exam 2 – Answers The

... 14. What are Cepheid variables? What two properties do they have that allow astronomers to use them to determine distances to very remote objects (like galaxies)? ...
Astronomy: Life Cycle of a Star
Astronomy: Life Cycle of a Star

... The light and heat from stars such as the Sun, is made by a process known as _________________________________. Fusion happens when two lightweight atoms are forced together to form a heavier one, producing a lot of ________________. However, fusion can only occur at the incredibly high ____________ ...
Slide 1 - cosmos.esa.int
Slide 1 - cosmos.esa.int

... “normal” supernovae, most of our intuition gained from these low-entropy models is not so useful for BH formation. • The neutrino signal from these collapses may be detectable. We need detailed spectra and details of formation. • We’re working on new models, requests taken. ...
Nuclear Structure`07: Exciting, Broad, Relevant
Nuclear Structure`07: Exciting, Broad, Relevant

... Nuclear structure. A FRIB would offer a laboratory for exploring the limits of nuclear existence and identifying new phenomena, with the possibility that a more broadly applicable theory of nuclei will emerge. FRIB would investigate new forms of nuclear matter such as the large neutron excesses occu ...
Document
Document

... – any region of space is about the same as any other ...
1.4 Whiteboard Review!
1.4 Whiteboard Review!

... decay of the following elements: • Uranium-234 (U, alpha decay) ...
The Mass of the Galaxy - University of California, Berkeley
The Mass of the Galaxy - University of California, Berkeley

... galaxy are just a pattern that may rotate slowly or not at all; individual stars will be passing through it all the time. ...
Stars and Galaxies PP 2013
Stars and Galaxies PP 2013

... High mass supergiants may undergo a supernova, where the core suddenly collapses and explodes. A neutron star is what remains after the supernova. It is composed mainly of neutrons and is very dense. If it spins and releases radiation it is called a pulsar. ...
Galactic chemical evolution of heavy elements: from Barium to
Galactic chemical evolution of heavy elements: from Barium to

... A quantitative understanding of the Galactic evolution of nuclei heavier than iron has been so far a challenging problem. Although some of the basic tools of this task have been presented several years ago, both from an observational (Spite & Spite 1978, 1979; Sneden & Parthasaraty 1983; Gilroy et a ...
Lec2015_22
Lec2015_22

... SMSSJ0313-6708: Abundance Results Can look at abundance of elements relative to Fe • [Fe/H] incredibly low – formed before SN Type Ia enrichment ...
Terrestrial aurora - Annales Geophysicae
Terrestrial aurora - Annales Geophysicae

... waves and particles. Particular observations include the fast (Temerin and Roth, 1992; Roth and Temerin, 1997). Both temporal electron and wave oscillations, as shown on Fig. 1, environments have very low β (thermal to magnetic pressure at a frequency of 120 Hz, below the hydrogen H+ gyrofreratio) p ...
Spacebook Research Project
Spacebook Research Project

... Page to make it look fancy. This is a template that I have already made for you that you can cut and paste!! Feel free to edit this page and creativity is worth extra credit!! We will cover all of the pieces of this essay in class though some of it will not be till the end of the unit. BiG BanG Ques ...
Chapter 17 Star Stuff
Chapter 17 Star Stuff

... Stellar Mass and Fusion • The mass of a main sequence star determines its core pressure and temperature • Stars of higher mass have higher core temperature and more rapid fusion, making those stars both more luminous and shorter-lived • Stars of lower mass have cooler cores and slower fusion rates, ...
sample
sample

... the story of the elements. In this case, the earliest form is still with us today. It is the element hydrogen, which still accounts for more than 75 per cent of the mass of the universe. All the other elements have come from hydrogen, directly or mostly indirectly by the fusion of lighter elements t ...
< 1 ... 58 59 60 61 62 63 64 65 66 ... 96 >

Nucleosynthesis



Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and neutrons. The first nuclei were formed about three minutes after the Big Bang, through the process called Big Bang nucleosynthesis. It was then that hydrogen and helium formed to become the content of the first stars, and this primeval process is responsible for the present hydrogen/helium ratio of the cosmos.With the formation of stars, heavier nuclei were created from hydrogen and helium by stellar nucleosynthesis, a process that continues today. Some of these elements, particularly those lighter than iron, continue to be delivered to the interstellar medium when low mass stars eject their outer envelope before they collapse to form white dwarfs. The remains of their ejected mass form the planetary nebulae observable throughout our galaxy.Supernova nucleosynthesis within exploding stars by fusing carbon and oxygen is responsible for the abundances of elements between magnesium (atomic number 12) and nickel (atomic number 28). Supernova nucleosynthesis is also thought to be responsible for the creation of rarer elements heavier than iron and nickel, in the last few seconds of a type II supernova event. The synthesis of these heavier elements absorbs energy (endothermic) as they are created, from the energy produced during the supernova explosion. Some of those elements are created from the absorption of multiple neutrons (the R process) in the period of a few seconds during the explosion. The elements formed in supernovas include the heaviest elements known, such as the long-lived elements uranium and thorium.Cosmic ray spallation, caused when cosmic rays impact the interstellar medium and fragment larger atomic species, is a significant source of the lighter nuclei, particularly 3He, 9Be and 10,11B, that are not created by stellar nucleosynthesis.In addition to the fusion processes responsible for the growing abundances of elements in the universe, a few minor natural processes continue to produce very small numbers of new nuclides on Earth. These nuclides contribute little to their abundances, but may account for the presence of specific new nuclei. These nuclides are produced via radiogenesis (decay) of long-lived, heavy, primordial radionuclides such as uranium and thorium. Cosmic ray bombardment of elements on Earth also contribute to the presence of rare, short-lived atomic species called cosmogenic nuclides.
  • studyres.com © 2025
  • DMCA
  • Privacy
  • Terms
  • Report