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A Galaxisok Világa Tóth L A galaxisok világa Tóth L. Viktor XML to PDF by RenderX XEP XSL-FO F ormatter, visit us at http://www.renderx.com/ A galaxisok világa Tóth L. Viktor Szerzői jog © 2013 Eötvös Loránd Tudományegyetem E könyv kutatási és oktatási célokra szabadon használható. Bármilyen formában való sokszorosítása a jogtulajdonos írásos engedélyéhez kötött. Készült a TÁMOP-4.1.2.A/1-11/1-2011-0073 számú, „E-learning természettudományos tartalomfejlesztés az ELTE TTK-n” című projekt keretében. Konzorciumvezető: Eötvös Loránd Tudományegyetem, konzorciumi tagok: ELTE TTK Hallgatói Alapítvány, ITStudy Hungary Számítástechnikai Oktató- és Kutatóközpont Kft. XML to PDF by RenderX XEP XSL-FO F ormatter, visit us at http://www.renderx.com/ Tartalom Előszó ........................................................................................................................................ vii 1. Bevezetés .................................................................................................................................. 1 1.1 Ködök ............................................................................................................................. 1 1.2. Világmodellek – a Shapley-Curtis vita ................................................................................. 4 1.2.1. A Shapley-Curtis vita főbb kérdései: ......................................................................... 5 1.2.2. A Shapley-Curtis vita tudományos előzményei és háttere: ............................................. 5 Referenciák és további olvasnivaló az előszó és az 1. fejezet témájában: ........................................... 7 2. Távolságmérés és az extragalaxisok felfedezése ............................................................................. 10 2.1. Trigonometrikus parallaxis, a parszek definíciója .................................................................. 10 2.2. A fotometriai (radiometriai) parallaxis módszerekről ............................................................. 11 2.3. Távolságmérési módszerek fajtái és hatókörük ..................................................................... 12 2.4. Spektroszkópiai parallaxis ................................................................................................ 13 2.5. A Tully-Fisher reláció ..................................................................................................... 13 2.6. A Faber-Jackson reláció ................................................................................................... 15 2.6.1. A D-σ reláció ...................................................................................................... 16 2.7. Távolságmérés felületi fényesség fluktuációjából .................................................................. 17 2.8. Ia típusú szupernóvák és távolságmérés .............................................................................. 18 2.9. A cefeida parallaxis ........................................................................................................ 23 2.9.1. A periódus-luminozitás reláció ............................................................................... 23 2.9.2. A cefeidák használatának előnye a távolság meghatározásban ....................................... 27 2.9.3. A cefeida pulzáló változók fizikai leírásának alapjai ................................................... 27 2.9.4. A periódus-luminozitás reláció alkalmazása a gyakorlatban .......................................... 28 2.10. A P-L módszer néhány tudománytörténetben fontos alkalmazása ........................................... 30 2.10.1. Shapley – távoli gömbhalmazok ............................................................................ 30 2.10.2. Hubble – vannak extragalaxisok ............................................................................ 31 2.10.3. A Hubble állandó ............................................................................................... 32 2.10.4. Sandage és Tamman – a Hubble állandó korrekciója .................................................. 33 2.11. Távolság meghatározása a Hubble törvénnyel ..................................................................... 33 Referenciák és további olvasnivaló a fejezet témájában: ............................................................... 35 3. Alaktani osztályozás, Hubble séma. .............................................................................................. 39 3.1 Hubble-Sandage osztályozás .............................................................................................. 39 3.1.1. A Hubble-féle osztályok – „hangvilla” ..................................................................... 40 3.1.2. A Hubble-féle morfológiai osztályozás hiányosságai ................................................... 52 3.1.3. A Hubble-féle osztályozás finomításai ..................................................................... 53 3.1.4. A Hubble osztályozásba nem illeszthető galaxisok ...................................................... 61 3.2. A morfológiai osztályozási sémák összehasonlítása ............................................................... 62 3.3. Fizikai paraméterek és szerkezet kapcsolata ......................................................................... 62 Referenciák és további olvasnivaló a fejezet témájában: ............................................................... 63 4. Elliptikus galaxisok ................................................................................................................... 66 4.1 Óriás és közepes elliptikus galaxisok ................................................................................... 66 4.1.1. Az elliptikus galaxisok morfológiája ........................................................................ 67 4.1.2. Az elliptikus galaxisok sűrűségmodellje ................................................................... 71 4.1.3. Az elliptikus galaxisok kinematikája ........................................................................ 73 4.1.4. Az elliptikus galaxisok csillagtartalma ..................................................................... 74 4.1.5. Csillagközi anyag elliptikus galaxisokban ................................................................. 74 4.1.6. Fekete lyuk elliptikus galaxisok középpontjában ........................................................ 74 4.1.7. Az elliptikus galaxisok eloszlása ............................................................................. 75 4.2 Törpe elliptikus galaxisok ................................................................................................. 75 Referenciák és további olvasnivaló a fejezet témájában: ............................................................... 76 5. Spirálgalaxisok ......................................................................................................................... 77 5.1. A galaxisok fő összetevői ................................................................................................. 77 5.2. Spirálkar indikátorok ....................................................................................................... 77 5.2.1. A spirálkarok megjelenési formái ............................................................................ 77 5.2.2. OB asszociációk és HII zónák ................................................................................ 78 5.2.3. Óriás molekulafelhők és HI szuperfelhők .................................................................. 78 iii XML to PDF by RenderX XEP XSL-FO F ormatter, visit us at http://www.renderx.com/ A galaxisok világa 5.3. Spirálgalaxisok alrendszerei ............................................................................................. 79 5.3.1. Korong .............................................................................................................. 80 5.3.2. Dudor – bulge ..................................................................................................... 82 5.3.3. Barionos, vagy csillagos halo ................................................................................. 84 5.3.4. Sötétanyag halo ................................................................................................... 85 5.4. Csillagközi anyag ........................................................................................................... 85 5.5. Forgás és rotációs görbe ................................................................................................... 89 5.5.1. Nyírási és forgási együtthatók, nyírási ráta ................................................................ 89 5.5.2. A rotációs görbe .................................................................................................. 89 5.6. A korong stabilitása ........................................................................................................ 89 5.7. Csillagkeletkezés ............................................................................................................ 91 5.7.1. A Schmidt-törvény ............................................................................................... 91 5.7.2. Spirálkarok és csillagkeletkezés .............................................................................. 92 Referenciák és további olvasnivaló a fejezet témájában: ............................................................... 94 6. Anomális galaxisok: kompakt és irreguláris rendszerek .................................................................... 96 6.1. Kék kompakt galaxisok
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