3397:
1455:
1017:
38:
3409:
2284:
62:
3445:
3469:
3100:
3421:
3457:
3433:
2057:
Comparing the mass of the final helium-4 atom with the masses of the four protons reveals that 0.7 percent of the mass of the original protons has been lost. This mass has been converted into energy, in the form of kinetic energy of produced particles, gamma rays, and neutrinos released during each
682:
This process, mediated by the strong nuclear force rather than the weak force, is extremely fast by comparison to the first step. It is estimated that, under the conditions in the Sun's core, each newly created deuterium nucleus exists for only about one second before it is converted into helium-3.
802:
0.02 percent. Since half the neutrinos produced in branches II and III are produced in the first step (synthesis of a deuteron), only about 8.35 percent of neutrinos come from the later steps (see below), and about 91.65 percent are from deuteron synthesis. However, another solar model from around
56:
fusion processes at different temperatures (T). The dashed line shows the combined energy generation of the PP and CNO processes within a star. At the Sun's core temperature of 15.5 million K the PP process is dominant. The PP process and the CNO process are equal at around 20
134:
are the much more common result of proton–proton reactions within the star, and diprotons almost immediately decay back into two protons. Since the conversion of hydrogen to helium is slow, the complete conversion of the hydrogen initially in the
814:
branch. Other even rarer reactions may occur. The rate of these reactions is very low due to very small cross-sections, or because the number of reacting particles is so low that any reactions that might happen are statistically insignificant.
2474:
of the same basic interaction, where the electron passes to the right side of the reaction as a positron. This is represented in the figure of proton–proton and electron-capture reactions in a star, available at the NDM'06 web site.
154:, a series of reactions. The product of one reaction is the starting material of the next reaction. There are two main chains leading from hydrogen to helium in the Sun. One chain has five reactions, the other chain has six.
803:
the same time gives only 7.14 percent of neutrinos from the later steps and 92.86 percent from the synthesis of deuterium nuclei. The difference is apparently due to slightly different assumptions about the composition and
686:
In the Sun, each helium-3 nucleus produced in these reactions exists for only about 400 years before it is converted into helium-4. Once the helium-3 has been produced, there are four possible paths to generate
2560:
See Figure 2. The caption is not very clear but it has been confirmed that the percentages refer to how much of each reaction takes place, or equivalently how much helium-4 is produced by each branch.
2097:
Neutrinos do not interact significantly with matter and therefore do not heat the interior and thereby help support the Sun against gravitational collapse. Their energy is lost: the neutrinos in the
2120:
rather than as neutrinos. The starting figures used are the ones mentioned higher in this article. The table concerns only the 99% of the power and neutrinos that come from the
2065:
Energy released as gamma rays will interact with electrons and protons and heat the interior of the Sun. Also kinetic energy of fusion products (e.g. of the two protons and the
1372:
Note that the energies in the second reaction above are the energies of the neutrinos that are produced by the reaction. 90 percent of the neutrinos produced in the reaction of
2949:
3132:
1856:
The last three stages of this chain, plus the positron annihilation, contribute a total of 18.209 MeV, though much of this is lost to the neutrino.
3082:
146:
in the normal sense. In most nuclear reactions, a chain reaction designates a reaction that produces a product, such as neutrons given off during
3396:
3104:
2925:
2570:
1901:
in the Sun). In this reaction, helium-3 captures a proton directly to give helium-4, with an even higher possible neutrino energy (up to
3489:
2718:
2614:
45:
3125:
2783:
2751:
104:, the other known reaction, is suggested by theoretical models to dominate in stars with masses greater than about 1.3
2866:
1442:
is about 0.862 MeV, almost all of which is lost to the neutrino if the decay goes directly to the stable lithium.
162:
The theory that proton–proton reactions are the basic principle by which the Sun and other stars burn was advocated by
3021:
Bellini, G.; et al. (2 February 2012). "First
Evidence of pep Solar Neutrinos by Direct Detection in Borexino".
3387:
3118:
2516:
Adelberger, Eric G.; et al. (12 April 2011). "Solar fusion cross sections. II. The pp chain and CNO cycles".
2117:
487:
2090:
reaction) adds energy to the plasma in the Sun. This heating keeps the core of the Sun hot and prevents it from
2049:
for the energy released by this reaction plus the ensuing annihilation, some of which is lost to the neutrino.
193:
attempted to calculate the rates of various reactions in stars. Starting with two protons combining to give a
3284:
3229:
3184:
521:
213:
201:
he found what we now call Branch II of the proton–proton chain. But he did not consider the reaction of two
3279:
3269:
2796:
Aldo
Serenelli; et al. (Nov 2009). "New Solar Composition: The Problem With Solar Models Revisited".
2091:
1875:
217:
527:
After it is formed, the deuteron produced in the first stage can fuse with another proton to produce the
2447:
released by the pep reaction are far more energetic: while neutrinos produced in the first step of the
2116:" coming from the three branches. "Luminosity" here means the amount of energy given off by the Sun as
3274:
3264:
3040:
2963:
Adelberger, E. G.; et al. (2010). "Solar fusion cross sections. II. Theppchain and CNO cycles".
2881:
2815:
2678:
2535:
2489:
53:
31:
1454:
3473:
3328:
3219:
3199:
3194:
2606:
1016:
166:
in the 1920s. At the time, the temperature of the Sun was considered to be too low to overcome the
1894:
This reaction is predicted theoretically, but it has never been observed due to its rarity (about
3461:
3449:
3064:
3030:
2990:
2972:
2943:
2831:
2805:
2551:
2525:
175:
182:
of the protons through the repulsive barrier allows for fusion at a lower temperature than the
3209:
3179:
3149:
3056:
2931:
2921:
2779:
2757:
2747:
2724:
2714:
2610:
2600:
2578:
2412:
2018:
1897:
1770:
1224:
501:: The relative amounts of energy going to the neutrino and to the other products is variable.
450:
326:
249:
183:
171:
120:
3425:
3413:
3239:
3204:
3189:
3141:
3048:
2982:
2889:
2823:
2686:
2543:
2296:
2113:
505:
163:
524:
of this reaction experimentally because it is so low but it can be calculated from theory.
37:
3494:
3349:
3244:
3214:
2669:
2471:
1025:
967:
but 2.2 percent of this energy (0.59 MeV) is lost to the neutrinos that are produced. The
504:
This is the rate-limiting reaction and is extremely slow due to it being initiated by the
252:(though a small amount of deuterium nuclei is produced by the "pep" reaction, see below):
237:
212:
nuclei (Branch I) which we now know to be important. This was part of the body of work in
167:
147:
2112:
The following table calculates the amount of energy lost to neutrinos and the amount of "
1416:. The difference is whether the lithium-7 produced is in the ground state or an excited (
3044:
2885:
2819:
2682:
2539:
2109:
chains carry away 2.0%, 4.0%, and 28.3% of the energy in those reactions, respectively.
3401:
3370:
3354:
2827:
528:
143:
112:
81:
17:
3483:
3259:
3174:
3068:
2994:
2555:
2835:
3437:
3333:
3052:
2629:
2283:
1874:
chain is not a major source of energy in the Sun, but it was very important in the
498:
379:
367:
179:
150:, that quickly induces another such reaction. The proton–proton chain is, like a
3159:
2385:
1797:
1719:
1586:
1520:
1147:
1088:
804:
568:
424:
276:
151:
116:
3310:
3164:
2986:
2894:
2547:
2359:
2308:
1940:
1612:
1417:
1293:
974:
928:
594:
375:
190:
136:
105:
2935:
3305:
3297:
3289:
3254:
3169:
2761:
2728:
2484:
1547:
1267:
1198:
1114:
767:
756:
647:
194:
127:
101:
49:
41:
3060:
2691:
2664:
3099:
2915:
2058:
of the individual reactions. The total energy yield of one whole chain is
142:
Although sometimes called the "proton–proton chain reaction", it is not a
2865:
Burbidge, E.; Burbidge, G.; Fowler, William; Hoyle, F. (1 October 1957).
2460:
2444:
2334:
2292:
2067:
1992:
1966:
1914:
1830:
1745:
1494:
1468:
1320:
1173:
1062:
1036:
901:
875:
849:
772:
689:
620:
541:
404:
371:
363:
301:
245:
233:
198:
131:
89:
2295:
can also be produced by the rare pep (proton–electron–proton) reaction (
2459:. Detection of solar neutrinos from this reaction were reported by the
1687:
1638:
831:
releasing 26.73 MeV of energy, some of which is lost to the neutrinos.
532:
241:
759:-7, which undergoes further reactions to produce two helium-4 nuclei.
96:. It dominates in stars with masses less than or equal to that of the
536:
517:
509:
494:
390:
260:
229:
93:
27:
One of the fusion reactions by which stars convert hydrogen to helium
3110:
3432:
3035:
2977:
2810:
2530:
1453:
1015:
36:
762:
About 99% of the energy output of the sun comes from the various
516:
waits 9 billion years before it successfully fuses with another
85:
3114:
2439:
In the Sun, the frequency ratio of the pep reaction versus the
2094:
under its own weight as it would if the sun were to cool down.
986:
chain proceeds at slow rate, resulting in a low production of
513:
97:
2774:
This time and the two other times above come from: Byrne, J.
2920:(Second, revised and enlarged ed.). Weinheim, Germany.
1420:) state, respectively. The total energy released going from
3081:
Int'l
Conference on Neutrino and Dark Matter, 7 Sept 2006,
2640:: 42, 59, (1971), The Proton type-nuclear fission reaction.
2455:, the pep reaction produces sharp-energy-line neutrinos of
711:, helium-4 is produced by fusing two helium-3 nuclei; the
770:. According to one model of the sun, 83.3 percent of the
486:(which is the same as the PEP reaction, see below) has a
119:) of the protons is high enough to overcome their mutual
228:
The first step in all the branches is the fusion of two
1878:
because it generates very high energy neutrinos (up to
111:
In general, proton–proton fusion can occur only if the
61:
2287:
Proton–proton and electron-capture reactions in a star
3385:
3363:
3342:
3319:
3228:
3148:
139:is calculated to take more than ten billion years.
2124:reactions, not the 1% coming from the CNO cycle.
382:and the energy of the neutrino, the net reaction
3011:, The University of Chicago Press, 1988, p. 354.
3126:
2575:Astronomy 162: Stars, Galaxies, and Cosmology
1863:chain is dominant if the temperature exceeds
236:. As the protons fuse, one of them undergoes
65:Scheme of the proton–proton branch I reaction
8:
2511:
2509:
2507:
2505:
1365:branch is dominant at temperatures of 18 to
971:branch is dominant at temperatures of 10 to
963:The complete chain releases a net energy of
30:"pp 1" redirects here. For other uses, see
3339:
3133:
3119:
3111:
2948:: CS1 maint: location missing publisher (
2602:Evolution of Stars and Stellar Populations
2599:Salaris, Maurizio; Cassisi, Santi (2005).
766:chains, with the other 1% coming from the
520:. It has not been possible to measure the
3034:
2976:
2893:
2809:
2778:, Dover Publications, Mineola, NY, 2011,
2690:
2529:
2840:Calculated from model AGSS09 in Table 3.
2746:(2nd ed.). Chichester: John Wiley.
2282:
2126:
794:branches is produced via branch I while
60:
3392:
2852:An Introduction to Stellar Astrophysics
2501:
2470:reactions can be seen as two different
1412:, while the remaining 10 percent carry
3007:Claus E. Rolfs and William S. Rodney,
2941:
2909:
2907:
2905:
44:of the relative energy output (ε) of
7:
2867:"Synthesis of the Elements in Stars"
2704:
2702:
2045:The mass–energy relationship gives
73:, also commonly referred to as the
25:
2798:The Astrophysical Journal Letters
2128:Luminosity production in the sun
810:There is also the extremely rare
3467:
3455:
3443:
3431:
3419:
3407:
3395:
3098:
2443:reaction is 1:400. However, the
2451:reaction range in energy up to
3053:10.1103/PhysRevLett.108.051302
374:from the environment into two
80:, is one of two known sets of
1:
2742:Phillips, Anthony C. (1999).
3105:Proton-proton chain reaction
2828:10.1088/0004-637X/705/2/L123
2776:Neutrons, Nuclei, and Matter
2665:"Energy Production in Stars"
2651:Introductory Nuclear Physics
130:-producing events are rare.
2914:Iliadis, Christian (2015).
2709:Iliadis, Christian (2007).
2303:
1909:
1463:
1031:
844:
798:produces 16.68 percent and
563:
386:
256:
170:. After the development of
3511:
2663:Hans Bethe (Mar 1, 1939).
1023:
29:
2987:10.1103/RevModPhys.83.195
2965:Reviews of Modern Physics
2895:10.1103/RevModPhys.29.547
2874:Reviews of Modern Physics
2571:"The Proton–Proton Chain"
2548:10.1103/RevModPhys.83.195
2518:Reviews of Modern Physics
2118:electromagnetic radiation
818:The overall reaction is:
174:, it was discovered that
3490:Nuclear fusion reactions
2917:Nuclear physics of stars
2711:Nuclear Physics of Stars
790:produced by the various
216:for which Bethe won the
3185:Double electron capture
3023:Physical Review Letters
3009:Cauldrons in the Cosmos
2713:. Weinheim: Wiley-VCH.
2472:Feynman representations
2463:collaboration in 2012.
1458:Proton–proton III chain
224:The proton–proton chain
214:stellar nucleosynthesis
121:electrostatic repulsion
2692:10.1103/PhysRev.55.434
2653:, Wiley, 1987, p. 537.
2288:
1876:solar neutrino problem
1459:
1021:
1020:Proton–proton II chain
218:Nobel Prize in Physics
66:
58:
18:Proton-proton reaction
2286:
1457:
1019:
158:History of the theory
64:
40:
3107:at Wikimedia Commons
2744:The Physics of Stars
2609:. pp. 119–121.
2490:Triple-alpha process
823:4 H + 2 e → He + 2 ν
240:, converting into a
3329:Photodisintegration
3250:Proton–proton chain
3220:Spontaneous fission
3200:Isomeric transition
3195:Internal conversion
3045:2012PhRvL.108e1302B
2886:1957RvMP...29..547B
2820:2009ApJ...705L.123S
2683:1939PhRv...55..434B
2607:John Wiley and Sons
2540:2011RvMP...83..195A
2129:
1408:carry an energy of
512:in the core of the
84:reactions by which
71:proton–proton chain
2850:LeBlanc, Francis.
2649:Kenneth S. Krane,
2289:
2127:
1460:
1022:
737:with pre-existing
506:weak nuclear force
67:
59:
3383:
3382:
3379:
3378:
3210:Positron emission
3180:Double beta decay
3142:Nuclear processes
3103:Media related to
2927:978-3-527-33649-4
2466:Both the pep and
2435:
2434:
2276:
2275:
2041:
2040:
1852:
1851:
1357:
1356:
959:
958:
678:
677:
482:
481:
378:. Including this
358:
357:
250:electron neutrino
172:quantum mechanics
16:(Redirected from
3502:
3472:
3471:
3470:
3460:
3459:
3458:
3448:
3447:
3446:
3436:
3435:
3424:
3423:
3422:
3412:
3411:
3410:
3400:
3399:
3391:
3340:
3240:Deuterium fusion
3205:Neutron emission
3190:Electron capture
3135:
3128:
3121:
3112:
3102:
3086:
3079:
3073:
3072:
3038:
3018:
3012:
3005:
2999:
2998:
2980:
2960:
2954:
2953:
2947:
2939:
2911:
2900:
2899:
2897:
2871:
2862:
2856:
2855:
2847:
2841:
2839:
2813:
2804:(2): L123–L127.
2793:
2787:
2772:
2766:
2765:
2739:
2733:
2732:
2706:
2697:
2696:
2694:
2660:
2654:
2647:
2641:
2627:
2621:
2620:
2596:
2590:
2589:
2587:
2586:
2577:. Archived from
2567:
2561:
2559:
2533:
2513:
2469:
2458:
2454:
2450:
2442:
2431:
2430:
2428:
2427:
2419:
2418:
2403:
2401:
2400:
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2366:
2351:
2349:
2348:
2341:
2340:
2326:
2324:
2323:
2316:
2315:
2304:
2297:electron capture
2279:The PEP reaction
2252:
2246:
2234:
2223:
2211:
2205:
2194:
2182:
2176:
2130:
2123:
2114:solar luminosity
2108:
2104:
2100:
2089:
2085:
2083:
2082:
2075:
2074:
2061:
2048:
2037:
2036:
2034:
2033:
2025:
2024:
2009:
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1999:
1998:
1984:
1982:
1981:
1974:
1973:
1958:
1956:
1955:
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1910:
1904:
1900:
1889:
1881:
1873:
1866:
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1846:
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1838:
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1815:
1813:
1812:
1805:
1804:
1788:
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1785:
1777:
1776:
1762:
1760:
1759:
1752:
1751:
1737:
1735:
1734:
1727:
1726:
1705:
1703:
1702:
1695:
1694:
1681:
1680:
1679:
1678:
1671:
1670:
1656:
1654:
1653:
1646:
1645:
1630:
1628:
1627:
1620:
1619:
1604:
1602:
1601:
1594:
1593:
1580:
1565:
1564:
1562:
1561:
1554:
1553:
1538:
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1528:
1527:
1512:
1510:
1509:
1502:
1501:
1486:
1484:
1483:
1476:
1475:
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1449:
1441:
1439:
1438:
1430:
1428:
1427:
1415:
1411:
1407:
1406:
1405:
1398:
1397:
1389:
1388:
1387:
1380:
1379:
1368:
1364:
1353:
1338:
1336:
1335:
1328:
1327:
1311:
1309:
1308:
1301:
1300:
1285:
1283:
1282:
1275:
1274:
1261:
1252:
1243:
1242:
1240:
1239:
1231:
1230:
1216:
1214:
1213:
1206:
1205:
1190:
1188:
1187:
1180:
1179:
1165:
1163:
1162:
1155:
1154:
1141:
1132:
1131:
1129:
1128:
1121:
1120:
1106:
1104:
1103:
1096:
1095:
1080:
1078:
1077:
1070:
1069:
1054:
1052:
1051:
1044:
1043:
1032:
1011:
1003:
1002:
1001:
994:
993:
985:
981:
977:
970:
966:
955:
946:
944:
943:
936:
935:
919:
917:
916:
909:
908:
893:
891:
890:
883:
882:
867:
865:
864:
857:
856:
845:
838:
827:
813:
801:
797:
793:
789:
787:
786:
779:
778:
765:
754:
753:
752:
745:
744:
736:
735:
734:
727:
726:
718:
714:
710:
706:
704:
703:
696:
695:
674:
665:
664:
662:
661:
654:
653:
638:
636:
635:
628:
627:
612:
610:
609:
602:
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586:
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583:
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431:
421:
419:
418:
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410:
387:
354:
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344:
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341:
333:
332:
318:
316:
315:
308:
307:
294:
292:
291:
284:
283:
257:
211:
209:
208:
164:Arthur Eddington
77:
21:
3510:
3509:
3505:
3504:
3503:
3501:
3500:
3499:
3480:
3479:
3478:
3468:
3466:
3456:
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3444:
3442:
3430:
3420:
3418:
3408:
3406:
3394:
3386:
3384:
3375:
3359:
3350:Neutron capture
3338:
3321:
3315:
3232:nucleosynthesis
3231:
3224:
3215:Proton emission
3170:Gamma radiation
3151:
3144:
3139:
3095:
3090:
3089:
3080:
3076:
3020:
3019:
3015:
3006:
3002:
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2957:
2940:
2928:
2913:
2912:
2903:
2869:
2864:
2863:
2859:
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2844:
2795:
2794:
2790:
2773:
2769:
2754:
2741:
2740:
2736:
2721:
2708:
2707:
2700:
2670:Physical Review
2662:
2661:
2657:
2648:
2644:
2628:
2624:
2617:
2598:
2597:
2593:
2584:
2582:
2569:
2568:
2564:
2515:
2514:
2503:
2498:
2481:
2467:
2456:
2452:
2448:
2440:
2426:
2423:
2422:
2421:
2417:
2415:
2414:
2413:
2411:
2410:
2399:
2397:
2396:
2395:
2391:
2388:
2387:
2386:
2384:
2373:
2371:
2370:
2369:
2365:
2362:
2361:
2360:
2358:
2347:
2345:
2344:
2343:
2339:
2337:
2336:
2335:
2333:
2322:
2320:
2319:
2318:
2314:
2311:
2310:
2309:
2307:
2281:
2250:
2244:
2232:
2221:
2209:
2203:
2192:
2180:
2174:
2165:
2163:
2158:
2156:
2155:Relative amount
2151:
2149:
2144:
2143:due to neutrino
2142:
2137:
2121:
2106:
2102:
2098:
2087:
2081:
2079:
2078:
2077:
2073:
2070:
2069:
2068:
2066:
2059:
2055:
2047:19.795 MeV
2046:
2032:
2029:
2028:
2027:
2023:
2021:
2020:
2019:
2017:
2016:
2005:
2003:
2002:
2001:
1997:
1995:
1994:
1993:
1991:
1980:
1978:
1977:
1976:
1972:
1969:
1968:
1967:
1965:
1954:
1952:
1951:
1950:
1946:
1943:
1942:
1941:
1939:
1928:
1926:
1925:
1924:
1920:
1917:
1916:
1915:
1913:
1902:
1895:
1892:
1887:
1879:
1871:
1864:
1860:
1844:
1842:
1841:
1840:
1836:
1833:
1832:
1831:
1829:
1811:
1809:
1808:
1807:
1803:
1800:
1799:
1798:
1796:
1784:
1781:
1780:
1779:
1775:
1773:
1772:
1771:
1769:
1758:
1756:
1755:
1754:
1750:
1748:
1747:
1746:
1744:
1733:
1731:
1730:
1729:
1725:
1722:
1721:
1720:
1718:
1701:
1699:
1698:
1697:
1693:
1690:
1689:
1688:
1686:
1677:
1675:
1674:
1673:
1669:
1667:
1666:
1665:
1664:
1663:
1652:
1650:
1649:
1648:
1644:
1641:
1640:
1639:
1637:
1626:
1624:
1623:
1622:
1618:
1615:
1614:
1613:
1611:
1600:
1598:
1597:
1596:
1592:
1589:
1588:
1587:
1585:
1578:
1560:
1558:
1557:
1556:
1552:
1550:
1549:
1548:
1546:
1545:
1534:
1532:
1531:
1530:
1526:
1523:
1522:
1521:
1519:
1508:
1506:
1505:
1504:
1500:
1497:
1496:
1495:
1493:
1482:
1480:
1479:
1478:
1474:
1471:
1470:
1469:
1467:
1452:
1447:
1437:
1435:
1434:
1433:
1432:
1426:
1424:
1423:
1422:
1421:
1413:
1409:
1404:
1402:
1401:
1400:
1396:
1394:
1393:
1392:
1391:
1386:
1384:
1383:
1382:
1378:
1376:
1375:
1374:
1373:
1366:
1362:
1351:
1334:
1332:
1331:
1330:
1326:
1323:
1322:
1321:
1319:
1307:
1305:
1304:
1303:
1299:
1296:
1295:
1294:
1292:
1281:
1279:
1278:
1277:
1273:
1270:
1269:
1268:
1266:
1259:
1250:
1238:
1235:
1234:
1233:
1229:
1227:
1226:
1225:
1223:
1222:
1212:
1210:
1209:
1208:
1204:
1201:
1200:
1199:
1197:
1186:
1184:
1183:
1182:
1178:
1176:
1175:
1174:
1172:
1161:
1159:
1158:
1157:
1153:
1150:
1149:
1148:
1146:
1139:
1127:
1125:
1124:
1123:
1119:
1117:
1116:
1115:
1113:
1112:
1102:
1100:
1099:
1098:
1094:
1091:
1090:
1089:
1087:
1076:
1074:
1073:
1072:
1068:
1065:
1064:
1063:
1061:
1050:
1048:
1047:
1046:
1042:
1039:
1038:
1037:
1035:
1028:
1026:Lithium burning
1014:
1009:
1000:
998:
997:
996:
992:
990:
989:
988:
987:
983:
979:
972:
968:
965:26.732 MeV
964:
954:12.859 MeV
953:
942:
940:
939:
938:
934:
931:
930:
929:
927:
915:
913:
912:
911:
907:
904:
903:
902:
900:
889:
887:
886:
885:
881:
878:
877:
876:
874:
863:
861:
860:
859:
855:
852:
851:
850:
848:
841:
836:
826:
822:
811:
799:
795:
791:
785:
783:
782:
781:
777:
775:
774:
773:
771:
763:
751:
749:
748:
747:
743:
741:
740:
739:
738:
733:
731:
730:
729:
725:
723:
722:
721:
720:
716:
712:
708:
702:
700:
699:
698:
694:
692:
691:
690:
688:
672:
660:
658:
657:
656:
652:
650:
649:
648:
646:
645:
634:
632:
631:
630:
626:
623:
622:
621:
619:
608:
606:
605:
604:
600:
597:
596:
595:
593:
582:
580:
579:
578:
574:
571:
570:
569:
567:
554:
552:
551:
550:
546:
544:
543:
542:
540:
476:
464:
461:
460:
459:
455:
453:
452:
451:
449:
448:
438:
436:
435:
434:
430:
427:
426:
425:
423:
417:
415:
414:
413:
409:
407:
406:
405:
403:
352:
340:
337:
336:
335:
331:
329:
328:
327:
325:
324:
314:
312:
311:
310:
306:
304:
303:
302:
300:
290:
288:
287:
286:
282:
279:
278:
277:
275:
238:beta plus decay
226:
207:
205:
204:
203:
202:
168:Coulomb barrier
160:
137:core of the Sun
75:
35:
28:
23:
22:
15:
12:
11:
5:
3508:
3506:
3498:
3497:
3492:
3482:
3481:
3477:
3476:
3464:
3452:
3440:
3428:
3416:
3404:
3381:
3380:
3377:
3376:
3374:
3373:
3371:(n-p) reaction
3367:
3365:
3361:
3360:
3358:
3357:
3355:Proton capture
3352:
3346:
3344:
3337:
3336:
3331:
3325:
3323:
3317:
3316:
3314:
3313:
3308:
3303:
3295:
3287:
3282:
3277:
3272:
3267:
3262:
3257:
3252:
3247:
3242:
3236:
3234:
3226:
3225:
3223:
3222:
3217:
3212:
3207:
3202:
3197:
3192:
3187:
3182:
3177:
3172:
3167:
3162:
3156:
3154:
3146:
3145:
3140:
3138:
3137:
3130:
3123:
3115:
3109:
3108:
3094:
3093:External links
3091:
3088:
3087:
3074:
3013:
3000:
2955:
2926:
2901:
2880:(4): 547–650.
2857:
2842:
2788:
2767:
2752:
2734:
2719:
2698:
2677:(5): 434–456.
2655:
2642:
2622:
2615:
2591:
2562:
2500:
2499:
2497:
2494:
2493:
2492:
2487:
2480:
2477:
2437:
2436:
2433:
2432:
2424:
2416:
2408:
2405:
2398:
2389:
2382:
2379:
2372:
2363:
2356:
2353:
2346:
2338:
2331:
2328:
2321:
2312:
2280:
2277:
2274:
2273:
2270:
2267:
2264:
2262:
2259:
2255:
2254:
2248:
2242:
2239:
2236:
2230:
2226:
2225:
2219:
2216:
2213:
2207:
2201:
2197:
2196:
2190:
2187:
2184:
2178:
2172:
2168:
2167:
2160:
2153:
2146:
2139:
2138:He-4 produced
2134:
2080:
2071:
2060:26.73 MeV
2054:
2053:Energy release
2051:
2043:
2042:
2039:
2038:
2030:
2022:
2014:
2011:
2004:
1996:
1989:
1986:
1979:
1970:
1963:
1960:
1953:
1944:
1937:
1934:
1927:
1918:
1891:
1884:
1880:14.06 MeV
1854:
1853:
1850:
1849:
1843:
1834:
1826:
1823:
1820:
1817:
1810:
1801:
1793:
1792:
1790:
1782:
1774:
1767:
1764:
1757:
1749:
1742:
1739:
1732:
1723:
1716:
1713:
1710:
1707:
1700:
1691:
1683:
1682:
1676:
1668:
1661:
1658:
1651:
1642:
1635:
1632:
1625:
1616:
1609:
1606:
1599:
1590:
1582:
1581:
1576:
1573:
1570:
1567:
1559:
1551:
1543:
1540:
1533:
1524:
1517:
1514:
1507:
1498:
1491:
1488:
1481:
1472:
1451:
1444:
1436:
1425:
1414:0.383 MeV
1410:0.861 MeV
1403:
1395:
1385:
1377:
1359:
1358:
1355:
1354:
1352:17.35 MeV
1349:
1346:
1343:
1340:
1333:
1324:
1316:
1313:
1306:
1297:
1290:
1287:
1280:
1271:
1263:
1262:
1260:0.383 MeV
1257:
1254:
1251:0.861 MeV
1248:
1245:
1236:
1228:
1220:
1217:
1211:
1202:
1195:
1192:
1185:
1177:
1170:
1167:
1160:
1151:
1143:
1142:
1137:
1134:
1126:
1118:
1110:
1107:
1101:
1092:
1085:
1082:
1075:
1066:
1059:
1056:
1049:
1040:
1013:
1006:
999:
991:
961:
960:
957:
956:
951:
948:
941:
932:
924:
921:
914:
905:
898:
895:
888:
879:
872:
869:
862:
853:
840:
833:
829:
828:
824:
784:
776:
750:
742:
732:
724:
719:branches fuse
701:
693:
680:
679:
676:
675:
673:5.493 MeV
670:
667:
659:
651:
643:
640:
633:
624:
617:
614:
607:
598:
591:
588:
581:
572:
553:
545:
508:. The average
484:
483:
480:
479:
477:1.442 MeV
474:
471:
462:
454:
446:
443:
437:
428:
416:
408:
400:
397:
394:
360:
359:
356:
355:
350:
347:
338:
330:
322:
319:
313:
305:
298:
295:
289:
280:
273:
270:
267:
264:
244:by emitting a
225:
222:
206:
197:nucleus and a
159:
156:
144:chain reaction
113:kinetic energy
100:, whereas the
82:nuclear fusion
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
3507:
3496:
3493:
3491:
3488:
3487:
3485:
3475:
3465:
3463:
3453:
3451:
3441:
3439:
3434:
3429:
3427:
3417:
3415:
3405:
3403:
3398:
3393:
3389:
3372:
3369:
3368:
3366:
3362:
3356:
3353:
3351:
3348:
3347:
3345:
3341:
3335:
3332:
3330:
3327:
3326:
3324:
3318:
3312:
3309:
3307:
3304:
3302:
3300:
3296:
3294:
3292:
3288:
3286:
3283:
3281:
3278:
3276:
3273:
3271:
3268:
3266:
3263:
3261:
3258:
3256:
3253:
3251:
3248:
3246:
3243:
3241:
3238:
3237:
3235:
3233:
3227:
3221:
3218:
3216:
3213:
3211:
3208:
3206:
3203:
3201:
3198:
3196:
3193:
3191:
3188:
3186:
3183:
3181:
3178:
3176:
3175:Cluster decay
3173:
3171:
3168:
3166:
3163:
3161:
3158:
3157:
3155:
3153:
3147:
3143:
3136:
3131:
3129:
3124:
3122:
3117:
3116:
3113:
3106:
3101:
3097:
3096:
3092:
3084:
3078:
3075:
3070:
3066:
3062:
3058:
3054:
3050:
3046:
3042:
3037:
3032:
3029:(5): 051302.
3028:
3024:
3017:
3014:
3010:
3004:
3001:
2996:
2992:
2988:
2984:
2979:
2974:
2970:
2966:
2959:
2956:
2951:
2945:
2937:
2933:
2929:
2923:
2919:
2918:
2910:
2908:
2906:
2902:
2896:
2891:
2887:
2883:
2879:
2875:
2868:
2861:
2858:
2853:
2846:
2843:
2837:
2833:
2829:
2825:
2821:
2817:
2812:
2807:
2803:
2799:
2792:
2789:
2785:
2781:
2777:
2771:
2768:
2763:
2759:
2755:
2749:
2745:
2738:
2735:
2730:
2726:
2722:
2720:9783527406029
2716:
2712:
2705:
2703:
2699:
2693:
2688:
2684:
2680:
2676:
2672:
2671:
2666:
2659:
2656:
2652:
2646:
2643:
2639:
2635:
2631:
2626:
2623:
2618:
2616:0-470-09220-3
2612:
2608:
2604:
2603:
2595:
2592:
2581:on 2016-06-20
2580:
2576:
2572:
2566:
2563:
2557:
2553:
2549:
2545:
2541:
2537:
2532:
2527:
2523:
2519:
2512:
2510:
2508:
2506:
2502:
2495:
2491:
2488:
2486:
2483:
2482:
2478:
2476:
2473:
2464:
2462:
2457:1.44 MeV
2453:0.42 MeV
2446:
2429:
2409:
2406:
2402:
2383:
2380:
2376:
2357:
2354:
2350:
2332:
2329:
2325:
2306:
2305:
2302:
2301:
2300:
2298:
2294:
2285:
2278:
2271:
2268:
2265:
2263:
2260:
2257:
2256:
2249:
2243:
2240:
2237:
2231:
2228:
2227:
2220:
2217:
2214:
2208:
2202:
2199:
2198:
2191:
2188:
2185:
2179:
2173:
2170:
2169:
2161:
2157:of luminosity
2154:
2147:
2140:
2135:
2132:
2131:
2125:
2119:
2115:
2110:
2095:
2093:
2084:
2063:
2052:
2050:
2035:
2015:
2012:
2008:
1990:
1987:
1983:
1964:
1961:
1957:
1938:
1935:
1931:
1912:
1911:
1908:
1907:
1906:
1903:18.8 MeV
1899:
1885:
1883:
1877:
1868:
1857:
1847:
1827:
1824:
1821:
1818:
1814:
1795:
1794:
1791:
1787:
1768:
1765:
1761:
1743:
1740:
1736:
1717:
1714:
1711:
1708:
1704:
1685:
1684:
1662:
1659:
1655:
1636:
1633:
1629:
1610:
1607:
1603:
1584:
1583:
1579:1.59 MeV
1577:
1574:
1571:
1568:
1563:
1544:
1541:
1537:
1518:
1515:
1511:
1492:
1489:
1485:
1466:
1465:
1462:
1461:
1456:
1445:
1443:
1419:
1370:
1350:
1347:
1344:
1341:
1337:
1317:
1314:
1310:
1291:
1288:
1284:
1265:
1264:
1258:
1255:
1249:
1246:
1241:
1221:
1218:
1215:
1196:
1193:
1189:
1171:
1168:
1164:
1145:
1144:
1140:1.59 MeV
1138:
1135:
1130:
1111:
1108:
1105:
1086:
1083:
1079:
1060:
1057:
1053:
1034:
1033:
1030:
1029:
1027:
1018:
1007:
1005:
976:
952:
949:
945:
925:
922:
918:
899:
896:
892:
873:
870:
866:
847:
846:
843:
842:
834:
832:
821:
820:
819:
816:
808:
806:
788:
769:
760:
758:
705:
684:
671:
668:
663:
644:
641:
637:
618:
615:
611:
592:
589:
585:
566:
565:
562:
561:
560:
557:
538:
534:
530:
525:
523:
522:cross-section
519:
515:
511:
507:
502:
500:
496:
492:
490:
475:
472:
467:
447:
444:
441:
420:
401:
398:
395:
392:
389:
388:
385:
384:
383:
381:
377:
373:
369:
365:
353:0.42 MeV
351:
348:
343:
323:
320:
317:
299:
296:
293:
274:
271:
268:
265:
262:
259:
258:
255:
254:
253:
251:
247:
243:
239:
235:
231:
223:
221:
219:
215:
200:
196:
192:
187:
185:
181:
180:wavefunctions
177:
173:
169:
165:
157:
155:
153:
149:
145:
140:
138:
133:
129:
124:
122:
118:
114:
109:
107:
103:
99:
95:
91:
87:
83:
79:
72:
63:
55:
51:
47:
46:proton–proton
43:
39:
33:
19:
3474:Solar System
3334:Photofission
3298:
3290:
3249:
3077:
3026:
3022:
3016:
3008:
3003:
2968:
2964:
2958:
2916:
2877:
2873:
2860:
2851:
2845:
2801:
2797:
2791:
2775:
2770:
2743:
2737:
2710:
2674:
2668:
2658:
2650:
2645:
2637:
2633:
2630:Ishfaq Ahmad
2625:
2601:
2594:
2583:. Retrieved
2579:the original
2574:
2565:
2521:
2517:
2465:
2438:
2290:
2152:energy lost
2141:Percent loss
2111:
2096:
2064:
2056:
2044:
1893:
1890:(Hep) branch
1869:
1858:
1855:
1371:
1360:
962:
830:
817:
809:
807:of the sun.
761:
685:
681:
526:
503:
488:
485:
380:annihilation
361:
227:
188:
186:prediction.
161:
141:
126:In the Sun,
125:
110:
106:solar masses
74:
70:
68:
3462:Outer space
3450:Spaceflight
3160:Alpha decay
3150:Radioactive
2971:: 195–245.
2634:The Nucleus
2166:luminosity
2145:production
805:metallicity
497:) of 1.442
152:decay chain
117:temperature
3484:Categories
3311:rp-process
3285:Si burning
3275:Ne burning
3245:Li burning
3165:Beta decay
3083:Session 14
2784:0486482383
2753:0471987972
2585:2018-07-30
2524:(1): 201.
2496:References
2229:Branch III
2162:Percentage
2136:Percent of
2092:collapsing
1865:25 MK
1431:to stable
1418:metastable
1367:25 MK
1024:See also:
980:10 MK
493:(released
376:gamma rays
368:annihilate
191:Hans Bethe
3426:Astronomy
3414:Chemistry
3322:processes
3306:p-process
3280:O burning
3270:C burning
3260:α process
3255:CNO cycle
3069:118444784
3036:1110.3230
2995:119117147
2978:1004.2318
2944:cite book
2936:908071061
2811:0909.2668
2556:119117147
2531:1004.2318
2485:CNO cycle
2445:neutrinos
2200:Branch II
2159:produced
2150:amount of
2086:from the
1896:0.3
768:CNO cycle
757:beryllium
220:in 1967.
195:deuterium
189:In 1939,
184:classical
176:tunneling
132:Diprotons
102:CNO cycle
42:Logarithm
3364:Exchange
3301:-process
3293:-process
3265:Triple-α
3061:22400925
2836:14323767
2762:40948449
2729:85897502
2479:See also
2461:Borexino
2293:deuteron
2171:Branch I
2164:of total
2148:Relative
978:. Below
973:18
755:to form
531:, light
372:electron
370:with an
364:positron
246:positron
234:deuteron
199:positron
128:deuteron
90:hydrogen
88:convert
54:Triple-α
3402:Physics
3388:Portals
3343:Capture
3230:Stellar
3041:Bibcode
2882:Bibcode
2816:Bibcode
2679:Bibcode
2536:Bibcode
2407:+
2381:→
2355:+
2330:+
2253:0.015%
2241:0.0057%
2133:Branch
2107:p–p III
2013:+
1988:+
1962:→
1936:+
1872:p–p III
1861:p–p III
1828:2
1825:→
1766:+
1741:+
1715:→
1660:+
1634:→
1608:+
1575:+
1542:+
1516:→
1490:+
1448:p–p III
1348:+
1315:→
1289:+
1256:/
1247:+
1219:+
1194:→
1169:+
1136:+
1109:+
1084:→
1058:+
950:+
926:2
923:+
897:→
871:+
800:p–p III
717:p–p III
669:+
642:+
616:→
590:+
533:isotope
473:+
422:→
396:+
349:+
272:→
266:+
248:and an
242:neutron
232:into a
230:protons
178:of the
148:fission
3495:Proton
3067:
3059:
2993:
2934:
2924:
2834:
2786:, p 8.
2782:
2760:
2750:
2727:
2717:
2613:
2554:
2420:ν
2404:
2378:
2352:
2327:
2247:0.014%
2224:16.4%
2206:16.68%
2195:83.6%
2105:, and
2103:p–p II
2026:ν
2010:
1985:
1959:
1933:
1888:p–p IV
1822:
1819:
1816:
1789:
1778:ν
1763:
1738:
1712:
1709:
1706:
1672:γ
1657:
1631:
1605:
1572:
1569:
1566:
1555:γ
1539:
1513:
1487:
1450:branch
1363:p–p II
1345:
1342:
1339:
1312:
1286:
1253:
1244:
1232:ν
1191:
1166:
1133:
1122:γ
1081:
1055:
1012:branch
1010:p–p II
982:, the
947:
920:
894:
868:
839:branch
812:p–p IV
796:p–p II
713:p–p II
666:
655:γ
639:
613:
587:
537:helium
529:stable
518:proton
510:proton
495:energy
470:
458:ν
393:
346:
334:ν
263:
94:helium
48:(PP),
3438:Stars
3320:Other
3152:decay
3065:S2CID
3031:arXiv
2991:S2CID
2973:arXiv
2870:(PDF)
2832:S2CID
2806:arXiv
2552:S2CID
2526:arXiv
2272:100%
2269:97.7%
2266:2.34%
2258:total
2238:28.3%
2235:0.02%
2218:16.0%
2215:0.67%
2189:81.6%
2186:1.67%
2177:83.3%
2099:p–p I
2088:p–p I
969:p–p I
837:p–p I
709:p–p I
707:. In
491:value
366:will
86:stars
78:chain
3057:PMID
2950:link
2932:OCLC
2922:ISBN
2780:ISBN
2758:OCLC
2748:ISBN
2725:OCLC
2715:ISBN
2611:ISBN
2261:100%
1886:The
1870:The
1859:The
1446:The
1361:The
1008:The
835:The
715:and
362:The
69:The
52:and
3049:doi
3027:108
2983:doi
2890:doi
2824:doi
2802:705
2687:doi
2544:doi
2468:p–p
2449:p–p
2441:p–p
2299:):
2122:p–p
1905:).
1898:ppm
1882:).
1390:to
984:p–p
792:p–p
764:p–p
535:of
514:Sun
499:MeV
98:Sun
92:to
76:p–p
57:MK.
50:CNO
32:Pp1
3486::
3063:.
3055:.
3047:.
3039:.
3025:.
2989:.
2981:.
2969:83
2967:.
2946:}}
2942:{{
2930:.
2904:^
2888:.
2878:29
2876:.
2872:.
2830:.
2822:.
2814:.
2800:.
2756:.
2723:.
2701:^
2685:.
2675:55
2673:.
2667:.
2636:,
2632:,
2605:.
2573:.
2550:.
2542:.
2534:.
2522:83
2520:.
2504:^
2291:A
2251:00
2233:00
2212:4%
2183:2%
2101:,
2076:He
2062:.
1975:He
1923:He
1867:.
1839:He
1806:Be
1728:Be
1595:Be
1529:Be
1503:He
1477:He
1440:Li
1429:Be
1399:Li
1381:Be
1369:.
1329:He
1318:2
1276:Li
1207:Li
1156:Be
1097:Be
1071:He
1045:He
1004:.
995:He
975:MK
910:He
884:He
858:He
780:He
746:He
728:He
697:He
629:He
559::
549:He
539:,
445:+
402:+
321:+
210:He
123:.
108:.
3390::
3299:s
3291:r
3134:e
3127:t
3120:v
3085:.
3071:.
3051::
3043::
3033::
2997:.
2985::
2975::
2952:)
2938:.
2898:.
2892::
2884::
2854:.
2838:.
2826::
2818::
2808::
2764:.
2731:.
2695:.
2689::
2681::
2638:1
2619:.
2588:.
2558:.
2546::
2538::
2528::
2425:e
2394:D
2390:1
2368:H
2364:1
2342:e
2317:H
2313:1
2245:0
2222:0
2210:0
2204:0
2193:0
2181:0
2175:0
2072:2
2031:e
2000:e
1971:2
1949:H
1945:1
1919:2
1835:2
1802:4
1783:e
1753:e
1724:4
1696:B
1692:5
1647:B
1643:5
1621:H
1617:1
1591:4
1525:4
1499:2
1473:2
1325:2
1302:H
1298:1
1272:3
1237:e
1203:3
1181:e
1152:4
1093:4
1067:2
1041:2
937:H
933:1
906:2
880:2
854:2
825:e
625:2
603:H
599:1
577:D
573:1
489:Q
463:e
433:D
429:1
412:e
399:p
391:p
339:e
309:e
297:+
285:D
281:1
269:p
261:p
115:(
34:.
20:)
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