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Triple-alpha process - Video Learning - WizScience.com
Triple-alpha process - Video Learning - WizScience.com
Published: 2015/09/29
Channel: Wiz Science™
Alpha Process - Je T
Alpha Process - Je T'aime
Published: 2015/01/10
Channel: Retro Trance Addict Belgium
Alpha Process Controls Marine ERC Coupling STS
Alpha Process Controls Marine ERC Coupling STS
Published: 2014/01/28
Channel: Alpha Process Controls
LawBreakers Dev Diary #5 | The Alpha Process
LawBreakers Dev Diary #5 | The Alpha Process
Published: 2016/06/13
Channel: LawBreakers
The Secret Meaning of Alpha Phi Alpha Fraternity Inc
The Secret Meaning of Alpha Phi Alpha Fraternity Inc
Published: 2016/05/24
Channel: Khui Land
Teach Astronomy - Triple-Alpha Process
Teach Astronomy - Triple-Alpha Process
Published: 2010/07/10
Channel: Teach Astronomy
Spit - The Alpha Process
Spit - The Alpha Process
Published: 2016/10/02
Channel: The Alpha Process
Triple-alpha process
Triple-alpha process
Published: 2016/01/29
Channel: WikiAudio
Alpha process
Alpha process
Published: 2016/01/22
Channel: WikiAudio
Everyn - Alpha Process
Everyn - Alpha Process
Published: 2015/05/19
Channel: EverynBand
Alpha Process Coaching  for Business Success
Alpha Process Coaching for Business Success
Published: 2008/11/21
Channel: William Smith
Behind The Scenes | Alpha Kappa Alpha Sorority, Inc. FA
Behind The Scenes | Alpha Kappa Alpha Sorority, Inc. FA'14 New Member Presentation`
Published: 2014/11/29
Channel: Ashley Whitney
Signs - Alpha Process
Signs - Alpha Process
Published: 2012/05/07
Channel: seventhirtytwo
Due Process - Full Tutorial w/ Developer! (Pre-Alpha)
Due Process - Full Tutorial w/ Developer! (Pre-Alpha)
Published: 2014/09/27
Channel: PartiallyRoyal
Triple Alpha Process
Triple Alpha Process
Published: 2015/01/10
Channel: Sara Paige
Alpha Process - Je T
Alpha Process - Je T'aime
Published: 2009/04/03
Channel: Greg Vse
Solar H-alpha Processing With Photoshop
Solar H-alpha Processing With Photoshop
Published: 2015/04/04
Channel: Steven Doye
Alpha Motivation -  Love the Process ft.  Eric Thomas
Alpha Motivation - Love the Process ft. Eric Thomas
Published: 2016/05/03
Channel: Alpha Wolf Motivation
Due Process: Alpha Teaser
Due Process: Alpha Teaser
Published: 2014/12/05
Channel: Mainjay21
Alpha Process - Je T
Alpha Process - Je T'aime (Original Mix)
Published: 2016/07/29
Channel: Bonzai Allstars
"Authenticity" by The Alpha Process
"Authenticity" by The Alpha Process
Published: 2012/09/23
Channel: thealphaprocess
BLACK BOOTS | Ep. 115 "Hell Week" + #ArtisticStandardTV | @BlackBootsTV (2015)
BLACK BOOTS | Ep. 115 "Hell Week" + #ArtisticStandardTV | @BlackBootsTV (2015)
Published: 2015/04/03
Channel: ARTISTIC STANDARD TV
Alpha Process - Je t
Alpha Process - Je t'aime (Kris Curvers 2015 Rework)
Published: 2015/07/26
Channel: Crystal Dream
Alpha Process   je t
Alpha Process je t'aime
Published: 2010/07/29
Channel: coolfrommix
Durst Alpha Series  - The Process Innovation for Digital Textile Print
Durst Alpha Series - The Process Innovation for Digital Textile Print
Published: 2015/11/09
Channel: Durst Group
How to Process the Horsehead Nebula (H-alpha) in PixInsight
How to Process the Horsehead Nebula (H-alpha) in PixInsight
Published: 2017/01/18
Channel: Chuck's Astrophotography
Alpha Racing BMW S 1000 RR Building Process
Alpha Racing BMW S 1000 RR Building Process
Published: 2016/04/29
Channel: kva-kva-kva-grin
Alpha process Top # 9 Facts
Alpha process Top # 9 Facts
Published: 2015/11/01
Channel: YourtIy1
BALLY ALPHA CLEAR PROCESS
BALLY ALPHA CLEAR PROCESS
Published: 2016/06/10
Channel: Bettor Slots
Bogota-The Alpha Process
Bogota-The Alpha Process
Published: 2016/11/02
Channel: The Alpha Process
Nuclear Fusion Explained
Nuclear Fusion Explained
Published: 2016/11/28
Channel: The Science Asylum
Alpha Process - Hearts Of Ascension (Original Mix)
Alpha Process - Hearts Of Ascension (Original Mix)
Published: 2016/07/29
Channel: Bonzai Allstars
Alpha-Process-Informatique
Alpha-Process-Informatique
Published: 2009/09/27
Channel: ImaGin68
Alpha Process Anger Control Coaching
Alpha Process Anger Control Coaching
Published: 2008/11/22
Channel: William Smith
Due Process Early Alpha - Episode 1
Due Process Early Alpha - Episode 1
Published: 2015/01/16
Channel: PauseUnpause
Due Process - Part 1: "Attack and Defend!" (Pre-Alpha Gameplay)
Due Process - Part 1: "Attack and Defend!" (Pre-Alpha Gameplay)
Published: 2014/09/28
Channel: PartiallyRoyal
Alpha Process - Walk In The Space (Original Mix)
Alpha Process - Walk In The Space (Original Mix)
Published: 2016/07/29
Channel: Bonzai Allstars
"Cthulhu" by The Alpha Process at Mother Live, London 14/11/12
"Cthulhu" by The Alpha Process at Mother Live, London 14/11/12
Published: 2012/11/18
Channel: thealphaprocess
DSG Alpha Holsters - Manufacturing Process
DSG Alpha Holsters - Manufacturing Process
Published: 2015/09/03
Channel: DSGArms
"I am the One" by The Alpha Process
"I am the One" by The Alpha Process
Published: 2012/09/23
Channel: thealphaprocess
"Was I Right?" by The Alpha Process - 1st gig 290812
"Was I Right?" by The Alpha Process - 1st gig 290812
Published: 2012/09/03
Channel: thealphaprocess
Due Process | Alpha Gameplay #1 - Getting Started
Due Process | Alpha Gameplay #1 - Getting Started
Published: 2015/01/16
Channel: hcjustin
Stars in Other Universes Including a Solution to the Triple Alpha Fine Tuning Problem by Fred Adams
Stars in Other Universes Including a Solution to the Triple Alpha Fine Tuning Problem by Fred Adams
Published: 2017/05/13
Channel: FQXi
Alpha Process - Je T
Alpha Process - Je T'aime.wmv
Published: 2010/12/23
Channel: CarpentierGlenn
Alpha Process Controls Cryogenic Breakaway Coupling Demonstration
Alpha Process Controls Cryogenic Breakaway Coupling Demonstration
Published: 2014/02/20
Channel: Alpha Process Controls
Elite: Dangerous Alpha Phase One
Elite: Dangerous Alpha Phase One
Published: 2013/12/12
Channel: Elite Dangerous
Triple Alpha Process - May 24, 2017
Triple Alpha Process - May 24, 2017
Published: 2017/06/02
Channel: Ayy Pneumatic
Due Process Gameplay │ Part 1 │ "Breach & Clear!" (Pre-Alpha)
Due Process Gameplay │ Part 1 │ "Breach & Clear!" (Pre-Alpha)
Published: 2014/09/30
Channel: EireBornFenix
StarTools: M42 H-alpha High Dynamic Range composite processing
StarTools: M42 H-alpha High Dynamic Range composite processing
Published: 2013/01/10
Channel: StarToolsAstro
Eta Pi Chapter of Kappa Alpha Psi - More than just a Process (Spring 2K11)
Eta Pi Chapter of Kappa Alpha Psi - More than just a Process (Spring 2K11)
Published: 2011/04/22
Channel: FlyyGuyFilms
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WIKIPEDIA ARTICLE

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The alpha process, also known as the alpha ladder, is one of two classes of nuclear fusion reactions by which stars convert helium into heavier elements, the other being the triple-alpha process.[1] The triple-alpha process consumes only helium, and produces carbon. After enough carbon has accumulated, the reactions below take place, also consuming only helium and the product of the previous reaction.

E  is the energy produced by the reaction, released primarily as gamma rays (γ).

This sequence ends at because it is the most stable (i.e., it has the highest nuclear binding energy per nucleon). Therefore, production of heavier nuclei requires energy (is endothermic) instead of releasing it (exothermic).

All these reactions have a very low rate at the temperatures and densities in stars and therefore do not contribute significantly to a star's energy production; with elements heavier than neon (atomic number > 10), they occur even less easily due to the increasing Coulomb barrier.

Alpha process elements (or alpha elements) are so-called since their most abundant isotopes are integer multiples of four, the mass of the helium nucleus (the alpha particle). Stable alpha elements are: C, O, Ne, Mg, Si, S, Ar, Ca. They are synthesized by alpha capture prior to the silicon fusing process, a precursor to Type II supernovae. Silicon and calcium are purely alpha process elements. Magnesium can be burned by proton capture reactions. As for oxygen, some authors[which?] consider it an alpha element, while others do not. Oxygen is surely an alpha element in low-metallicity population II stars. It is produced in Type II supernovae and its enhancement is well correlated with an enhancement of other alpha process elements. Sometimes carbon and nitrogen are considered alpha process elements, since they are synthesized in nuclear alpha-capture reactions.

The abundance of alpha elements in stars is usually expressed in a logarithmic manner:

,

Here and are the number of alpha elements and iron nuclei per unit volume. Theoretical galactic evolution models predict that early in the universe there were more alpha elements relative to iron. Type II supernovae mainly synthesize oxygen and the alpha-elements (Ne, Mg, Si, S, Ar, Ca and Ti) while Type Ia supernovae mainly produce elements of the iron peak (Ti, V, Cr, Mn, Fe, Co and Ni) but also alpha-elements.

References[edit]

  1. ^ Narlikar, Jayant V (1995). From Black Clouds to Black Holes. World Scientific. ISBN 9810220332. 

External links[edit]

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