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The Assembly History of Disk Galaxies: I - The Tully-Fisher Relation to z~1.3 from Deep Exposures with DEIMOS

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 Added by Sarah Miller
 Publication date 2011
  fields Physics
and research's language is English




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We present new measures of the evolving scaling relations between stellar mass, luminosity and rotational velocity for a morphologically-inclusive sample of 129 disk-like galaxies with z_AB<22.5 in the redshift range 0.2<z<1.3, based on spectra from DEIMOS on the Keck II telescope, multi-color HST ACS photometry, and ground-based Ks-band imaging. A unique feature of our survey is the extended spectroscopic integration times, leading to significant improvements in determining characteristic rotational velocities for each galaxy. Rotation curves are reliably traced to the radius where they begin to flatten for ~90% of our sample, and we model the HST-resolved bulge and disk components in order to accurately de-project our measured velocities, accounting for seeing and dispersion. We demonstrate the merit of these advances by recovering an intrinsic scatter on the stellar mass Tully-Fisher relation a factor of 2-3 less than in previous studies at intermediate redshift and comparable to that of locally-determined relations. With our increased precision, we find the relation is well-established by <z>~1, with no significant evolution to <z>~0.3, DeltaM_stellar ~ 0.04+/-0.07 dex. A clearer trend of evolution is seen in the B-band Tully-Fisher relation corresponding to a decline in luminosity of DeltaM_B ~ 0.85+/-0.28 magnitudes at fixed velocity over the same redshift range, reflecting the changes in star formation over this period. As an illustration of the opportunities possible when gas masses are available for a sample such as ours, we show how our dynamical and stellar mass data can be used to evaluate the likely contributions of baryons and dark matter to the assembly history of spiral galaxies.



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138 - Sarah H. Miller 2012
Through extended integrations using the recently-installed deep depletion CCD on the red arm of the Keck I Low Resolution Imaging Spectrograph, we present new measurements of the resolved spectra of 70 morphologically-selected star-forming galaxies with i_AB<24.1 in the redshift range 1<z<1.7. Using the formalism introduced in Paper I of this series and available HST ACS images, we successfully recover rotation curves using the extended emission line distribution of [O II] 3727 A to 2.2 times the disk scale radius for a sample of 42 galaxies. Combining these measures with stellar masses derived from HST and ground-based near-infrared photometry enables us to construct the stellar mass Tully-Fisher relation in the time interval between the well-constructed relation defined at z~1 in Paper I and the growing body of resolved dynamics probed with integral field unit spectrographs at z>2. Remarkably, we find a well-defined Tully-Fisher relation with up to 60% increase in scatter and stellar mass zero-point shift constraint of 0.02+/-0.02 dex since z~1.7, compared to the local relation. Although our sample is incomplete in terms of either a fixed stellar mass or star formation rate limit, we discuss the implications that typical star-forming disk galaxies evolve to arrive on a well-defined Tully-Fisher relation within a surprisingly short period of cosmic history.
We explore the use of the baryonic Tully-Fisher relation (bTFR) as a new distance indicator. Advances in near-IR imaging and stellar population models, plus precise rotation curves, have reduced the scatter in the bTFR such that distance is the dominant source of uncertainty. Using 50 galaxies with accurate distances from Cepheids or tip magnitude of the red giant branch, we calibrate the bTFR on a scale independent of $H_o$. We then apply this calibrated bTFR to 95 independent galaxies from the SPARC sample, using CosmicFlows-3 velocities, to deduce the local value of $H_o$. We find $H_o$ = 75.1 +/- 2.3 (stat) +/- 1.5 (sys) km s$^{-1}$ Mpc$^{-1}$.
We confirm the detection of 3 groups in the Lynx supercluster, at z~1.3, and give their redshifts and masses. We study the properties of the group galaxies as compared to the central clusters, RXJ0849+4452 and RXJ0848+4453, selecting 89 galaxies in the clusters and 74 galaxies in the groups. We morphologically classify galaxies by visual inspection, noting that our early-type galaxy (ETG) sample would have been contaminated at the 30% -40% level by simple automated classification methods (e.g. based on Sersic index). In luminosity selected samples, both clusters and groups show high fractions of Sa galaxies. The ETG fractions never rise above ~50% in the clusters, which is low compared to the fractions observed in clusters at z~1. However, ETG plus Sa fractions are similar to those observed for ETGs in clusters at z~1. Bulge-dominated galaxies visually classified as Sas might also be ETGs with tidal features or merger remnants. They are mainly red and passive, and span a large range in luminosity. Their star formation seems to have been quenched before experiencing a morphological transformation. Because their fraction is smaller at lower redshifts, they might be the spiral population that evolves into ETGs. For mass-selected samples, the ETG fraction show no significant evolution with respect to local clusters, suggesting that morphological transformations occur at lower masses and densities. The ETG mass-size relation shows evolution towards smaller sizes at higher redshift in both clusters and groups, while the late-type mass-size relation matches that observed locally. The group ETG red sequence shows lower zero points and larger scatters than in clusters, both expected to be an indication of a younger galaxy population. The estimated age difference is small when compared to the difference in age at different galaxy masses.
In order to explore local large-scale structures and velocity fields, accurate galaxy distance measures are needed. We now extend the well-tested recipe for calibrating the correlation between galaxy rotation rates and luminosities -- capable of providing such distance measures -- to the all-sky, space-based imaging data from the Wide-field Infrared Survey Explorer (WISE) W1 ($3.4mu$m) and W2 ($4.6mu$m) filters. We find a linewidth to absolute magnitude correlation (known as the Tully-Fisher Relation, TFR) of $mathcal{M}^{b,i,k,a}_{W1} = -20.35 - 9.56 (log W^i_{mx} - 2.5)$ (0.54 magnitudes rms) and $mathcal{M}^{b,i,k,a}_{W2} = -19.76 - 9.74 (log W^i_{mx} - 2.5)$ (0.56 magnitudes rms) from 310 galaxies in 13 clusters. We update the I-band TFR using a sample 9% larger than in Tully & Courtois (2012). We derive $mathcal{M}^{b,i,k}_I = -21.34 - 8.95 (log W^i_{mx} - 2.5)$ (0.46 magnitudes rms). The WISE TFRs show evidence of curvature. Quadratic fits give $mathcal{M}^{b,i,k,a}_{W1} = -20.48 - 8.36 (log W^i_{mx} - 2.5) + 3.60 (log W^i_{mx} - 2.5)^2$ (0.52 magnitudes rms) and $mathcal{M}^{b,i,k,a}_{W2} = -19.91 - 8.40 (log W^i_{mx} - 2.5) + 4.32 (log W^i_{mx} - 2.5)^2$ (0.55 magnitudes rms). We apply an I-band -- WISE color correction to lower the scatter and derive $mathcal{M}_{C_{W1}} = -20.22 - 9.12 (log W^i_{mx} - 2.5)$ and $mathcal{M}_{C_{W2}} = -19.63 - 9.11 (log W^i_{mx} - 2.5)$ (both 0.46 magnitudes rms). Using our three independent TFRs (W1 curved, W2 curved and I-band), we calibrate the UNION2 supernova Type Ia sample distance scale and derive $H_0 = 74.4 pm 1.4$(stat) $pm 2.4$(sys) kms$^{-1}$ Mpc$^{-1}$ with 4% total error.
115 - M. Puech 2009
[abr.] Using the multi-integral-field spectrograph GIRAFFE at VLT, we previsouly derived the stellar-mass Tully-Fisher Relation (smTFR) at z~0.6, and found that the distant relation is systematically offset by roughly a factor of two toward lower masses. We extend the study of the evolution of the TFR by establishing the first distant baryonic TFR. To derive gas masses in distant galaxies, we estimate a gas radius and invert the Schmidt-Kennicutt law between star formation rate and gas surface densities. We find that gas extends farther out than the UV light from young stars, a median of ~30%. We present the first baryonic TFR (bTFR) ever established at intermediate redshift and show that, within an uncertainty of +/-0.08 dex, the zeropoint of the bTFR does not appear to evolve between z~0.6 and z=0. The absence of evolution in the bTFR over the past 6 Gyr implies that no external gas accretion is required for distant rotating disks to sustain star formation until z=0 and convert most of their gas into stars. Finally, we confirm that the larger scatter found in the distant smTFR, and hence in the bTFR, is caused entirely by major mergers. This scatter results from a transfer of energy from bulk motions in the progenitors, to random motions in the remnants, generated by shocks during the merging. Shocks occurring during these events naturally explain the large extent of ionized gas found out to the UV radius in z~0.6 galaxies. All the results presented in this paper support the ``spiral rebuilding scenario of Hammer and collaborators, i.e., that a large fraction of local spiral disks have been reprocessed during major mergers in the past 8 Gyr.
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