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The Link Between Galaxy Morphology and Star Formation Activity and Its Evolution

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The Link Between Galaxy Morphology and Star Formation Activity and Its Evolution Technische Universit¨atM¨unchen Excellence Cluster Universe The link between galaxy morphology and star formation activity and its evolution Laura Morselli Vollst¨andigerAbdruck der von der Fakult¨atf¨urPhysik der Technischen Univer- sit¨atM¨unchen zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften (Dr. rer. nat.) genehmigten Dissertation. Vorsitzender: Prof. Dr. Bj¨ornGarbrecht Pr¨uferder Dissertation: 1. Prof. Dr. Elisa Resconi 2. Prof. Dr. Sherry Suyu Die Dissertation wurde am 16.01.2018 bei der Technischen Universit¨atM¨unchen eingereicht und durch die Fakult¨atf¨urPhysik am 12.03.2018 angenommen. To my family Contents 1 A framework for galaxy formation and evolution1 1.1 Galaxy Formation . .3 1.1.1 The cosmological framework . .3 1.1.2 Density perturbations and their growth . .5 1.1.3 First collapsed structures . .7 1.1.4 Galaxy formation . .8 1.2 Properties of galaxies . 10 1.2.1 Morphological classification of galaxies . 10 1.2.2 A global bimodality . 14 1.2.3 Star formation activity evolution . 21 1.2.4 The Main Sequence of SFGs . 22 1.2.5 From star forming to passive: the quenching mechanism . 25 1.3 Open questions . 28 2 The morphology - star formation activity link at low redshift 31 2.1 Introduction . 31 2.2 Dataset . 31 2.2.1 SFRs, stellar masses, and velocity dispersion . 32 2.2.2 The bulge/disk decomposition catalogue . 32 2.2.3 Galaxy host halo mass . 33 2.2.4 The galaxy sample . 34 2.3 Estimate of the central BH mass . 38 2.4 Bulge/disk decomposition reliability: comparison with other works 39 2.5 Results . 44 2.5.1 The B/T across the LogSFR - LogM? plane . 44 2.5.2 The effect of bars . 50 2.5.3 σe, LogMBH and R90=R50 in the LogSFR - LogM? plane . 51 2.5.4 Bulge and disk colours in the LogSFR - LogM? plane . 54 2.5.5 The reddening of the disk . 57 2.5.6 Driving galaxies below the MS . 59 2.6 Discussion and conclusions . 60 3 The effect of disc inclination on the main sequence of star-forming galaxies 67 3.1 Introduction . 67 v Contents 3.2 Dataset . 68 3.2.1 SFRs and stellar masses . 68 3.2.2 Bulge-disk decomposition: B/T and disk inclination angle 68 3.2.3 The final catalogue . 74 3.3 Inclination effects on the SFR - M? relation . 75 3.4 Discussion . 80 3.4.1 Interpretation of the inclination effects . 80 3.4.2 Effects on the Main Sequence . 82 3.4.3 Contaminating the Green Valley . 83 3.4.4 Conclusions . 85 4 Spatial distribution of stellar mass and star formation activity at higher redshift 87 4.1 Introduction . 87 4.2 Data . 88 4.2.1 Redshifts, Stellar Masses, SFRs and structural parameters 89 4.2.2 Final Sample . 90 4.2.3 Main Sequence definition . 91 4.2.4 Maps creation . 92 4.2.5 Structural parameters from GALFIT . 95 4.2.6 Radial profiles creation . 97 4.3 Results . 97 4.3.1 SFR, M?, and sSFR profiles . 97 4.3.2 Stacked maps . 102 4.4 Discussion . 105 4.4.1 SFR and sSFR profiles at low redshift . 105 4.4.2 SFR and sSFR profiles at high redshift . 107 4.4.3 Stellar mass distribution across - along the MS . 108 4.4.4 Moving galaxies across the MS and implications on quench- ing mechanism . 109 4.4.5 Summary . 110 5 Conclusions 113 Acknowledgements 117 vi List of Figures 1.1 The Hubble eXtreme Deep Field (XDF) . .2 1.2 CMB temperature map . .4 1.3 Merger tree representation for hierarchical structure formation. .7 1.4 The Hubble tuning fork diagram. 12 1.5 S´ersicindex in the LogM? - LogSFR plane. 14 1.6 Bimodal distribution of galaxies in the color - mass diagram. 15 1.7 Spectra of galaxies belonging to different morphological classes. 16 1.8 Luminosity functions of galaxies with different morphology. 18 1.9 Morphology-density relation. 19 1.10 The cosmic evolution of star formation rate density. 20 1.11 Three-dimensional SFR-M? relation for local galaxies. 23 1.12 Luminosity functions of observed and simulated galaxies . 26 2.1 B/Tg - B/Tr correlation . 33 2.2 Distribution of galaxies in our sample in the LogSFR - LogM? plane 35 2.3 Mz - stellar mass relation . 36 2.4 Completeness in the (g r)-LogM? and LogSFR - LogM? planes . 37 − 2.5 The LogMBH distribution in the LogM?-LogSFR plane. 40 2.6 B/T from BUDDA versus B/T GIM2D. 41 2.7 Comparison between B/T from GIM2D and GalazyZoo. 42 2.8 The B/T distribution in the local Universe. 44 2.9 Fraction of galaxies with a given B/T versus distance from the MS. 46 2.10 The B/T distribution in the local Universe: Sref .......... 47 2.11 Huertas-Company et al. (2011) morphological classification . 48 2.12 The mass-derived B/T distribution in the local Universe. 49 2.13 The BUDDA B/T distribution. 51 2.14 Bulge velocity dispersion distribution . 52 2.15 Black hole mass distribution . 53 2.16 Concentration parameter in the LogSFR - LogM? plane . 54 2.17 Galaxy, disk and bulge colours in the LogSFR - LogM? plane. 55 2.18 Balmer decrement in the LogSFR - LogM? plane. 56 2.19 Disk colour as a function of LogMBH -B/T-LogMhalo-LogM? .... 57 2.20 ∆MS as a function of LogMBH /B/T/LogMhalo ........... 60 2.21 B/T as a function of ∆MS computed from sSFRdisk......... 63 vii List of Figures 3.1 B/T in the LogSFR - LogM? plane for 0:02 < z < 0:2. 69 3.2 Disk inclination: S11 vs single S´ersicmodelling . 70 3.3 Disk inclination angle in different B/T bins . 71 3.4 SFR indicator in the LogSFR - LogM? plane . 73 3.5 Average disk inclination in the LogSFR - LogM? plane . 74 3.6 Total SFR distribution as a function of disk inclination . 76 3.7 Fiber SFR distribution . 78 3.8 SFR distribution in bulge+disk systems . 79 3.9 Fiber B/T as a function of disk inclination . 80 3.10 Effects of disk inclination on the MS . 82 3.11 Disk inclination as a function of ∆MS ................ 84 4.1 The HDUV survey coverage . 89 4.2 ∆MS - LogM? plane at 0:2 < z < 1:2 ................ 92 4.3 Stellar masses: comparison with Whitaker et al. (2014) . 93 4.4 Examples of mass, SFR, LUV and E(B-V) maps. 94 4.5 Structural parameters in this work and vdW12 . 96 4.6 SFR, M? and sSFR profiles (in kpc) of low-z sample. 98 4.7 SFR, M? and sSFR profiles (in R/Re) of low-z sample. 99 4.8 SFR, M? and sSFR profiles (in kpc) of high-z sample. 100 4.9 SFR, M? and sSFR profiles (in R/Re) of high-z sample. 101 4.10 S´ersicindex as a function of ∆MS .................. 103 4.11 Stacked SFR, M?, sSFR, LUV and E(B-V) maps . 104 5.1 Comparison SFRSED - SFROII .................... 115 viii List of Tables 2.1 Main sequence SFRs (first column) and dispersion values (second column) in bins of stellar mass, in Log(M/M ) (third column). 36 4.1 Number of galaxies in each bin of distance from the MS, stellar mass, and redshift. 92 ix Tante cose ho imparato da voi uomini... Ho imparato che tutti quanti vogliono vivere sulla cima della montagna, senza sapere che la vera felicit´asta nel come questa montagna ´estata scalata. Ho imparato che quando un bambino appena nato stringe con il suo piccolo pugno, per la prima volta, il dito del padre, lo racchiude per sempre. Ho imparato che un uomo ha diritto a guardarne un altro dall'alto solo per aiutarlo ad alzarsi. Gabriel Garcia Marquez 1 A framework for galaxy formation and evolution In the northern hemisphere, the night sky is riddled with specks of light of varying colours. Most of these points are stars belonging to the galaxy where our Solar System is located: the Milky Way. In the southern hemisphere two extended concentrations of stars are visible with the naked eye. They are systems outside our Galaxy: the Small Magellanic Cloud and the Large Magellanic Cloud. For long humans believed that the Milky Way was the only galaxy in the Universe. At the end of the 18th century, the first catalogue of nebulae (diffuse celestial objects) appeared. The author of the catalogue, Charles Messier, still believed that nebulae were objects belonging to the Milky Way. In the following decades, the number of observed nebulae increased steeply, and the first distinctions based on their shape were made. Only at the beginning of the 20th century, spec- troscopic studies and measurements of the luminosity of nebulae revealed that some of them were moving away from the Earth and were characterised by a weaker luminosity with respect to the typical luminosity of nebulae closer to the Earth. Edwin Hubble interpreted nebulae properties to conclude that they were sources outside the Milky Way. Due to that interpretation, together with the work of several astronomers, the idea of multiple galaxies in the Universe started spreading. Nowadays it is well known that galaxies characterise the largest part of the Uni- verse's history. Galactic structures, in fact, are observed up to redshift 11, when the Universe was only 3% of its current age (Oesch et al., 2016). Latest≈ studies estimate that in the Universe there are approximately 2 trillion galaxies (Conselice et al., 2016).
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