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Properties of Giant Extragalactic HII Regions and the Hubble Constant

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Properties of Giant Extragalactic HII Regions and the Hubble Constant Properties of giant extragalactic HII regions and the Hubble constant by David Fern´andezArenas Thesis submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY IN ASTROPHYSICS at the Instituto Nacional de Astrof´ısica, Optica´ y Electr´onica May 2018 Tonantzintla, Puebla Under the supervision of: Dr Roberto Terlevich Dr Elena Terlevich Dr Manolis Plionis ©INAOE 2018 The author hereby grants to INAOE permission to reproduce and to distribute publicly paper and electronic copies of this thesis document in whole or in part. Dedicated to my mother, my father, my sister, my brother, and especially to my wife Andrea, for being there always supporting me. Ainulindal¨e ...The human mind, endowed with the powers of generalization and abstraction, sees not only green-grass, discriminating it from other things (and finding it fair to look upon), but sees that it is green as well as being grass.... -The mind that thought of light, heavy, grey, yellow, still, swift, also conceived of magic that would make heavy things light and able to fly, turn grey lead into yellow gold, and the still rock into a swift water... J. R. R. Tolkien I Acknowledgements It is necessary the same compromise to write a thesis that to select the best words to thank all people that have contributed to this process. Firstly, I would like to express my sincere acknowledgements to my advisors Dr. Roberto Terlevich, Dr. Elena Terlevich, for their knowledge, patience and advice offered over the last years, to my teachers in special to Dr. Manolis Plionis. I would like to thank the rest of my thesis committee: Dr. Daniel Rosa Gonz´alez,Dr. M´onicaRodr´ıguezand Dr. Divakara Mayya. I am also very grateful to all the staff of the OAGH and OAN-SPM for made my observing runs easier and for all their help. I also thank my thesis evaluation committee: Dr. Casiana Mu˜noz-Tu˜n´on,Dr. Anna Lia Longinotti, Dr. S´ebastienFromenteau, Dr. Vahram Chavushyan, for taking the time to review this manuscript. I would like to thank the CONACyT without their scholarship (No. 360396), this thesis would not have been possible. Last, but no least, I would like to thank my friends Diego, Zavala, Alejandro, Ricardo L., Izbeth and Ricardo C., with who I was sharing amazing adventures during all this time in Mexico. Thanks to my family for their love and their help in finding my way through life. III Declaration I hereby declare that the present thesis entitled: Properties of giant extragalactic H ii regions and the Hubble constant was composed by myself, that the work con- tained herein is my own, except for that jointly- authored publications included, and that it has not been submitted for any other degree or professional qualification, at any other Research Institute or University. Parts of this work have already been published in refereed journals as follows: • The work presented in Chapter3 and Chapter4 was accepted to be published in Monthly Notices of the Royal Astronomical Society as An independent de- termination of the local Hubble constant. (Fernandez-Arenas´ et al., 2018) • The section 2.5 is presented in Melnick et al. (2017). Including D. Fernandez´ Arenas was published in Astronomy & Astrophysics as The L σ relation for − HII galaxies in green V Abstract The relationship between the integrated Hβ line luminosity and the velocity dis- persion of the ionized gas of H ii galaxies (HIIGs) and giant H ii 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 Hub- ∼ ble 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 possible 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 classifi- cation 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 (M σ) for HIIGs and GHIIRs, with that followed by old stellar B − systems as globular clusters, elliptical galaxies and bulges of spiral galaxies. To this end we have evolved the relation M σ during 12 Gyrs and we found that after dy- B − namic 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. VII 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. VIII Resumen La relacion´ entre la luminosidad integrada de la l´ınea de Hβ y la dispersion´ de ve- locidades del gas ionizado de galaxias H ii (GsHII) y regiones H ii gigantes (RsHIIG), representa una exitante candela estandar´ que puede ser usada con la instrumentacion´ actual hasta corrimientos al rojo z 3:5. Localmente es usada para obtener medidas ∼ precisas de la constante de Hubble combinando la pendiente de la relacion´ obtenida de GsHII cercanas (z 0.2) y el punto cero determinado de las RsHIIG. Esta tesis pre- ≤ tende contribuir con una nueva calibracion´ del punto zero de la relacion´ L(Hβ) σ − con el fin de obtener una determinacion´ local de la constante de Hubble a traves´ de un analisis´ detallado de los posibles efectos sistematicos´ asociados con la relacion´ L(Hβ) σ y su impacto en el valor de H0. − Hemos probado la validez de los tamanos˜ de las galaxias H ii como un segundo parametro´ que reduce la dispersion´ de esta correlacion.´ Presentamos tambien´ una clasificacion´ morfologica´ y de acuerdo a los perfiles en las l´ıneas de emision´ de es- tos objetos. Tambien´ estimamos las masas dinamicas´ y fotometricas´ y las compara- mos para probar el escenario gravitacional como el origen de los movimientos su- personicos´ en estas regiones masivas de formacion´ estelar. Finalmente, comparamos la relacion´ existente entre la magnitud absoluta en el azul y la dispersion´ de velocidades (M σ) para galaxias H ii y regiones H ii gigantes B − con aquella seguida por sistemas estelares viejos como cumulos´ globulares, galaxias el´ıpticas y bulbos de galaxias espirales. Hemos evolucionado la relacion´ M σ B − durante 12 Giga-anos˜ y encontramos que despues´ de la evolucion´ dinamica´ y estelar todos los sistemas siguen igual relacion´ sugiriendo una posible conexion´ evolutiva. En general, analizamos un posible escenario del origen de la correlacion´ L(Hβ) σ − IX seguida por GsHII y RsHIIG y su uso para determinar localmente el valor de la constante de Hubble. Al final de la Tesis, he agregado dos apendices;´ A: donde resumo los metodos´ normalmente utilizados para determinar la constante de Hubble. B: se refiere a los datos utilizados para este trabajo donde muestro los espectros obtenidos para mi muestra y sus imagenes´ en Hα tomadas de NED. X Contents Acknowledgements III DeclarationV Abstract VII ResumenIX 1 Introduction1 1.1 Motivations and aims of this work......................5 1.2 Structure of this Work.............................6 2 Properties of H ii Galaxies and Giant H ii Regions 9 2.1 H ii Galaxies, Blue Compact Dwarfs and Green Peas...........9 2.2 Giant extragalactic H ii regions and H ii galaxies............ 11 2.2.1 Morphology and structure...................... 14 2.2.2 Age of H ii galaxies.......................... 14 2.2.3 Chemical composition of H ii galaxies............... 17 2.2.4 H ii regions kinematics........................ 18 2.2.5 L(Hβ) σ relation of H ii galaxies................. 20 − 2.3 The physics of the L(Hβ) σ relation.................... 22 − 2.3.1 Age effects................................ 25 XI 2.3.2 Extinction effects............................ 25 2.3.3 Metallicity effects............................ 25 2.3.4 Size effect................................ 26 2.4 H ii galaxies as Distance Indicators and cosmological probes...... 26 2.5 L σ relation in green and the Hubble constant.............. 30 − 3 The determination of the Hubble constant: The anchor sample 33 3.1 The actual sample................................ 34 3.1.1 The GHIIR sample........................... 35 3.1.2 H ii galaxies.............................. 48 3.2 Data analysis.................................. 51 3.2.1 Extinction and underlying absorption................ 51 3.2.2 Evolution correction.......................... 53 3.2.3 Distances and luminosities...................... 57 3.2.4 L(Hβ) σ relation for the GHIIRs.................. 59 − 4 The determination of the Hubble constant: The method 63 4.0.1 Methodology.............................. 63 4.1 Systematics.................................... 65 4.1.1 Exploring the parameter space.................... 65 4.1.2 Summary of systematics effects.................... 74 4.2 Comparison with SNIa and Planck CMB.................. 75 4.3 Conclusions on H0 ............................... 77 5 The size role in the L σ relation for massive stellar clusters. 81 − 5.1 The sample...................................
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