J. Klappa and D. Bahenab
a Instituto Nacional de Investigaciones Nucleares, Km. 36.5 Carretera México–Toluca, 52750, Edo. de México, México, e–mail: klapp@nuclear.inin.mx.
b Institute of Astronomy of the Academy of Sciences, Bocnill 1401, 14131 Praha 4, Czech Republic, e–mail: bahen@hotmail.com.
Recibido el 1 de marzo de 2008
Aceptado el 25 de junio de 2008
]]> Abstract
A generation of stars which formed from primordial nearly pure H/He gas, the so–called first stars or Population III stars, must have existed since heavy elements can only be synthesized in the interior of the stars. These stars were responsible for the initial heavy elements enrichment of the intergalactic medium. In this work we analyze the possible outcome of the evolution of very massive Population III stars and whether their final fate can avoid the pair instability supernovae explosion. We have recently calculated the evolution and nucleosynthesis of mass losing very massive population III stars during the hydrogen and helium burning phases, and proposed a new scenario for the first stars in the universe. According to this scenario, the first stars were born very massive, but evolve with mass loss, and its possible endpoint is a hypernovae stage. At low metallicity the effects on the presupernova structure depends on the initial mass and the mass loss rate during the main sequence evolution. Presupernova stars of lower metallicity have different characteristics depending if they are galactic or pregalactic, and if they evolve without or with mass loss. When these stars evolve with mass loss, their convective core size increase and their helium– or carbon–oxygen core mass decreases. Then, the stars could explode like hypernovae or supernovae.
Keywords: First stars – stars: Population III; stellar evolution; mass loss; final fate.
Resumen
Una primera generación de estrellas formada de gas primordial casi puro de H y He, las llamadas primeras estrellas o estrellas de Población III, debió haber existido ya que los elementos pesados solo pueden ser sintetizados en el interior de las estrellas. Estas estrellas fueron responsables del enriquecimiento inicial del medio intergaláctico en elementos pesados. En este trabajo, analizamos el posible desenlace de la evolución de estrellas muy masivas de la Población III y cuando, su destino final, puede evitar la explosión de supernova por inestabilidad de pares. Recientemente hemos calculado la evolución y nucleosíntesis de estrellas muy masivas de población III con pérdida de masa durante los quemados de hidrógeno y helio, y propuesto un nuevo escenario para las primeras estrellas del universo. De acuerdo a este escenario, las primeras estrellas nacieron muy masivas pero evolucionaron con perdida de masa terminando su vida como hipernovas. A baja metalicidad los efectos de la estructura presupernova depende de la masa inicial y de la tasa de perdida de masa durante la secuencia principal. Las estrellas de presupernova de baja metalicidad tienen diferentes características dependiendo de si son galácticas o pregalácticas y si evolucionan con o sin pérdida de masa. Cuando evolucionan con pérdida de masa, el tamaño de su núcleo convectivo aumenta y las masas de sus nucleos de helio o de carbono–oxígeno disminuyen. Por consiguiente, estas estrellas podrían explotar como supernovas o hipernovas.
Descriptores: Primeras estrellas – estrellas: Población III, evolución estelar; pérdida de masa; destino final.
PACS: 97.10.Cv; 97.10.Me; 97.10.Zr; 97.20.Wt
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Acknowledgments
This work has been partially supported by the Mexican Consejo Nacional de Ciencia y Tecnología (CONACyT), and the German Deutscher Akademischer Austauschdienst (DAAD). One of us (D.B.) thank CONACYT for financial support. The calculations for this paper were performed by computer system in the Institute of Astronomy of the Academy of Sciences, Czech Republic, the Instituto Nacional de Investigaciones Nucleares (Draco), the Universidad Nacional Autónoma de México (Kambalam) and the Universidad de Sonora (Mezquite).
References
1. B.J. Carr, ARA & A 32 (1994) 531. [ Links ]
2. N.Y. Gnedin and J.P. Ostriker, ApJ 400 (1992) 1. [ Links ]
3. J. Klapp, Ap & SS 93 (1983) 313. [ Links ]
4. J. Klapp, Ap & SS 106 (1984) 215. [ Links ]
5. N. Yoshida, V. Bromm, and L. Hernquist, ApJ 605 (2004) 579. [ Links ]
6. A. Heger, S.A. Woosley, and R. Waters, in The First Stars, MPA/ESO Workshop, eds. A. Weiss, T.G. Abel, and V. Hill, Springer, (2000) p.121. [ Links ]
7. S.E. Woosley, T.A. Weaver, in Supernovae: A Survey of Current Research, eds. M.J. Rees and R.J. Stonham, Reidel, (1082) p.79. [ Links ]
8. S.E. Woosley and T.A. Weaver, ARA & A, 24 (1986) 205. [ Links ]
9. S.E. Woosley and T.A. Weaver, in Radiation Transport and Hydrodynamics, IAU Coll. 89, eds. D. Mihalas and K.H. Wrinkler (Reidel, 1986). [ Links ]
10. V. Bromm and A. Loeb, New Astron. 9 (2004) 353. [ Links ]
11. D.L. Fryer, S.E. Woosley, and A. Heger, ApJ 550 (2001) 372. [ Links ]
12. A. Heger and S.E. Woosley, Ap J 567 (2002) 532. [ Links ]
13. A. Heger et al., Ap J 591 (2003) 288. [ Links ]
14. V. Bromm and R.B. Larson, ARA & A 42 (2004) 79. [ Links ]
15. J.M. Tumlinson and A. Shull, Ap J 528 (2000) L65. [ Links ]
16. M. Tegmark et al., Ap J 474 (1997) 1. [ Links ]
17. K. Nomoto et al., in A Massive Star Odyssey: From main Sequenxe to Supernova, eds. K. van der Hucht, A. Herrero and C. Esteban, IAU Symp. 212, (2003) p.305. [ Links ]
18. K. Nomoto et al., Mem. S.A. It. 75 (2004) 312. [ Links ]
19. K. Nomoto et al., in The Fate of the Most Massive Stars, eds. R. Humphreys and K. Stanek, ASP Conf. Ser. 332, (2005) p.384. [ Links ]
20. H. Umeda and K. Nomoto, ApJ 565 (2002) 385. [ Links ]
21. H. Umeda and K. Nomoto, Nature 422 (2003) 871. [ Links ]
22. J. Tumlinson, A. Venkatesan, and J.M. Shull, ApJ 612 (2004) 602. [ Links ]
23. W.A. Fowler and F. Hoyle, ApJS 9 (1964) 201. [ Links ]
24. J.R. Bond, W.D. Arnett, and B.J. Carr, in Supernova: A Survey of Current Research, eds. M.J. Rees, R.J. Stoneham, Reidel, (1982) p.303. [ Links ]
25. V. Bromm, N. Yoshida, and L. Hernquist, ApJ 596 (2003) L135. [ Links ]
26. Y.–Z Qian and G.J. Wasserburg, ApJ 567 (2002) 515. [ Links ]
27. C. Chiosi, in The First Stars, ESO/WPA Workshop, eds. A. Weiss, T. Abel and V. Hill (Springer, 2000) p.323. [ Links ]
28. K. Iwamoto et al., Nature 395 (1998) 672. [ Links ]
29. K. Nomoto et al., in Supernova and Gamma Ray Burst, eds. M. Livio, Panagia and K. Sahu, (Cambridge, 2001), p. 144. [ Links ]
30. P.A. Mazzali et al., ApJ 572 (2002) L61. [ Links ]
31. D. Bahena, PhD Thesis, (2006), UK, Praha. [ Links ]
32. J. Klapp, D. Bahena, M.G. Corona–Galindo, in Gravitation and Cosmology, eds. A. Macias, C. Lämmerzahl and D. Nuñez, Melville N.Y., AIP Conf. Proc. 758 (2005) p.153. [ Links ]
33. M.F. El Eid, K.J. Fricke, and W.W. Ober, A & A 119 (1983) 54. [ Links ]
34. P. Marigo, C. Chiosi, and R.P. Kudritzki, A & A 399 (2003) 617. [ Links ]
35. S.E. Woosley, A. Heger, and T.A. Weaver, in Rev. Mod. Phys. 74 (2002) 1015. [ Links ]
36. S.P. Oh, ApJ 553 (2001) 499. [ Links ]
37. H. Umeda and K. Nomoto, (arXiv: astro–ph/0308029), (2004). [ Links ]
38. Y.–Z. Qian and G.J. Wasserburg, ApJ 559 (2001) 925. [ Links ]
39. J.W. Truran, J.J. Cowan, C.A. Pilachowski, and C. Sneden, PASP 114 (2002) 1293. [ Links ]
40. H. Umeda, K. Nomoto, T.G. Tsuru, and H. Matsumoto, ApJ 758 (2002) 885. [ Links ] ]]>