Properties of giant extragalactic HII regions and the Hubble constant
The relationship between the integrated Hβ line luminosity and the velocity dispersión of the ionized gas of HII galaxies (HIIGs) and giant HII regions (GHIIRs) represents an exciting standard candle that with present instrumentation can be used up to redshifts z ∼3:5. Locally it is used to obtain p...
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| Tipo de recurso: | tesis doctoral |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2018 |
| País: | México |
| Institución: | Instituto Nacional de Astrofísica, Óptica y Electrónica |
| Repositorio: | Repositorio Institucional del INAOE |
| Idioma: | inglés |
| OAI Identifier: | oai:inaoe.repositorioinstitucional.mx:1009/1909 |
| Acceso en línea: | http://inaoe.repositorioinstitucional.mx/jspui/handle/1009/1909 |
| Access Level: | acceso abierto |
| Palabra clave: | info:eu-repo/classification/Inspec/Hubble constant info:eu-repo/classification/Inspec/Star formation info:eu-repo/classification/Inspec/HII galaxies info:eu-repo/classification/Inspec/Extragalactic HII regions info:eu-repo/classification/cti/1 info:eu-repo/classification/cti/21 |
| Sumario: | The relationship between the integrated Hβ line luminosity and the velocity dispersión of the ionized gas of HII galaxies (HIIGs) and giant HII regions (GHIIRs) represents an exciting standard candle that with present instrumentation can be used up to redshifts z ∼3:5. Locally it is used to obtain precise measurements of the Hubble constant by combining the slope of the relation obtained from nearby (z ≤ 0.2) HIIGs with the zero point determined from GHIIRs. This thesis aims to contribute with a new calibration of the zero point of the L⎯ σ relation in order to obtain a determination of the local Hubble constant through a detailed analysis of the posible systematic effects associated with the L(Hβ) ⎯ σ relation and their impact in the value of the Hubble constant. We have tested the possibility of using the sizes of HIIGs as a second parameter in order to reduce the scatter of this correlation. We present a morphological classification according to the emission line profiles of these objects. We also estimated the dynamical and photometric masses and compared them to test the gravity scenario as the origin of the supersonic motions in these massive star forming regions. Finally, we compared the existing relation between absolute blue magnitude and velocity dispersion (MB ⎯ σ ) for HIIGs and GHIIRs, with that followed by old stellar systems as globular clusters, elliptical galaxies and bulges of spiral galaxies. To this end we have evolved the relation MB ⎯ σ during 12 Gyrs and we found that after dynamic and stellar evolution is taken into account, all systems follow the same relation suggesting a possible parentage line. In general, we analysed a possible scenario of the origin of the L(Hβ) ⎯ σ relation followed by HIIGs and GHIIRs and its use to determine locally the value of H₀. At the end of the Thesis I have added two appendices: A, based on the literature, summarizes the methods normally used for determining distances, and for calculating the Hubble constant; B pertains to the data used for this work and shows the spectra obtained for my sample of objects and their images in Hα taken from NASA/IPAC Extragalactic Database. |
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