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Galactic Astronomy 銀河物理学特論 I Lecture 3-2: Evolution of Luminosity Functions of Galaxies Seminar: Lily et al. 1995, ApJ, 455, 108 Lecture:. 2011/12/12. Local universe: Luminosity Function of Each Morphological Type
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Galactic Astronomy銀河物理学特論 ILecture 3-2: Evolution of Luminosity Functions of GalaxiesSeminar: Lily et al. 1995, ApJ, 455, 108 Lecture: 2011/12/12
Local universe: Luminosity Function of Each Morphological Type The overall shapes of the luminosity functions are well described with Schechter luminosity funtion. Phi(L) = (Phi*/L*) (L/L*)^alpha exp(-L/L*) Three parameters: Normalization (Phi*), characteristic luminosity (L*, knee of LF), faint end slope (alpha). Nakamura et al. 2003, ApJ, 125, 1682
Local universe: Luminosity Function of Each Morphological Type Total luminosity = Phi* L* Gamma(2+alpha) Is dominated by galaxies around the “knee” of the luminosity function if alpha>-2. Density evolution: Phi* changes Luminosity evolution L* changes Nakamura et al. 2003, ApJ, 125, 1682
CFHT-Multi-Object-Spectrograph: Multi slit spectroscopy Multi object spectrograph used for the Canada-France Redshift Survey. The system use multi slit mask to observe many objects at once. http://www.cfht.hawaii.edu/Instruments/Spectroscopy/SIS/Manual/chapter2_5.html#81 LeFevre et al. 1995, ApJ, 455, 60
Hawaii-survey: Galaxy spectroscopic survey with Keck/LRIS. On the contrary to the low-redshift universe, even K-band bright massive galaxies show large SFR at high-redshifts. Cowie et al. 1996, ApJ, 112, 839
Rest-frame UV-luminosity function and star formation rate density in the universe: Reddy et al. 2008, ApJS, 175, 48 Madau et al. 1996, MNRAS, 283, 1388
COMBO-17: In stead of conducting massive spectroscopic survey, they attached 12 narrow-band and 5 broad-band filters to 2m telescope and conducted multi-color survey in wide field. They determined the redshifts of galaxies with multi-band “photometric” redshifts. They discuss the evolution of luminosity function dividing their sample with SED type. Wolf et al. 2003, A&A, 401, 73
The K20 survey: Evolution of luminosity function is discussed with galaxy samples selected based on K-band magnitude. Most of the previous surveys use optical selections, but NIR selection is better to select galaxies based on their stellar mass. Pozzetti et al. 2003, A&A, 402, 837
The DEEP survey: Large spectroscopic survey with 8-10m class telescope with Keck DEIMOS Blue galaxies Red galaxies Willmer et al. 2006, ApJ, 647, 853
The VIMOS-VLT deep survey (VVDS): Evolution of galaxy luminosity function evaluated with spectroscopic redshift survey with VLT/VIMOS. Ilbert et al. 2005, A&A, 439, 863
GOODS: Hubble Space Telescope wide field survey with Advanced Camera for Surveys. Dahlen et al. 2005, ApJ, 631, 126
GOODS: Wide field of view of HST/ACS makes possible to evaluate evolution of luminosity function as a function of galaxy morphology. Ilbert et al. 2006, A&A, 453, 809
Extending to higher and higher redshifts: Bouwens et al. 2011,
Summary: Spectroscopic survey: + Single-band or Two-bands imaging data: (CFHT) Red or Blue galaxies + Multi-color data (Keck LRIS): evolution by SED type + Wide field NIR imaging data (ex. MOIRC): galaxy selection based on their stellar mass (+establishment of photometric redshift estimation) + “Massive” redshift survey with 8-10m class multi-slit spectrograph (Keck/DEIMOS, VLT/VIMOS) + Availability of high-resolution imaging data from HST in the optical band:luminosity function by morphological type + Longer wavelength data from Spitzer/IRAC: The discussion on “luminosity” function moved into the discussion on “stellar mass” function. The results can be compared with the theoretical cosmological models of galaxy formation more directly.