相关论文: The Spheroid Luminosity and Mass Functions From HS…

Using data from the Sloan Digital Sky Survey Early Data Release and SuperCOSMOS Sky Survey scans of POSS-I plates we identify a sample of 2600 subdwarfs using reduced proper motion methods and strict selection criteria. This forms one of…

We study a sample of 257 Galactic disk M dwarfs (8<M_V<18.5) found in images obtained using HST. These include 192 stars in 22 fields imaged with the repaired WFC2 with mean limiting mag I=23.7 and 65 stars in 162 fields imaged with the…

We present the stellar mass functions (SMF) and mass densities of galaxies, and their spheroid and disk components in the local (z~0.1) universe over the range 8.9 <= log(M/M_solar) <= 12 from spheroid+disk decompositions and corresponding…

We report on new measurements of the luminosity function (LF) and mass function (MF) of field low-mass dwarfs derived from Sloan Digital Sky Survey (SDSS) Data Release 6 (DR6) photometry. The analysis incorporates ~15 million low-mass stars…

We report on a new measurement of the luminosity function (LF) and mass function (MF) of field low-mass dwarfs using Sloan Digital Sky Survey (SDSS) photometry. The final catalog is composed of ~15 million low-mass stars (0.1 Msun < M < 0.8…

Using the Galactica code of Benson et al., we obtain quantitative measurements of spheroid-to-disk ratios for a sample of 8839 galaxies observed in the Sloan Digital Sky Survey. We carry out extensive tests of this code and of Gim2D,…

We use recent low-mass star models, which reproduce accurately the observed sequences of various globular clusters, to convert the observed luminosity functions into bolometric luminosity functions and mass functions down to the bottom of…

We study a sample of about 1400 disk M dwarfs that are found in 148 fields observed with the Wide Field Camera 2 (WFC2) on the Hubble Space Telescope and 162 fields observed with pre-repair Planetary Camera 1 (PC1), of which 95 of the WFC2…

We present measurements of the luminosity and mass functions of low-mass stars constructed from a catalog of matched Sloan Digital Sky Survey (SDSS) and 2 Micron All Sky Survey (2MASS) detections. This photometric catalog contains more than…

We show that faint red stars do not contribute significantly to the mass budget of the Galaxy or to microlensing statistics. Our results are obtained by analyzing two long exposures of a high-latitude field taken with the Wide Field Camera…

We present a magnitude and proper motion limited catalogue of ~10,000 white dwarf candidates, obtained from the SuperCOSMOS Sky Survey by means of reduced proper motion selection. This catalogue extends to magnitudes r~19.75 and proper…

From high-resolution images of 23 Seyfert-1 galaxies at z=0.36 and z=0.57 obtained with the Near Infrared Camera and Multi-Object Spectrometer on board the Hubble Space Telescope (HST), we determine host-galaxy morphology, nuclear…

[Abridged] We present new measurements of the H-alpha luminosity function (LF) and SFR volume density for galaxies at z~0.8. Our analysis is based on 1.18$\mu$m narrowband data from the NEWFIRM H-alpha Survey, a comprehensive program…

We present final Spitzer trigonometric parallaxes for 361 L, T, and Y dwarfs. We combine these with prior studies to build a list of 525 known L, T, and Y dwarfs within 20 pc of the Sun, 38 of which are presented here for the first time.…

We analyse the bulge/spheroid size-(stellar mass), $R_{\rm e,Sph}-M_{\rm *,Sph}$, relation and spheroid structural parameters for 202 local (predominantly $\lesssim 110~\rm Mpc$) galaxies spanning $ M_*\sim 3\times10^{9}-10^{12}~\rm…

The amount of mass contained in low-mass objects is investigated anew. Instead of using a mass-luminosity relation to convert a luminosity function to a mass function, I predict the mass-luminosity relation from assumed mass functions and…

As part of a global analysis of deep star counts to constrain scenarii of galaxy formation and evolution, we investigate possible links between the galactic spheroid and the dark matter halo. A wide set of deep star counts at high and…

Monte Carlo simulations of the field substellar mass function (MF) are presented. Starting from various representations of the MF below 0.1 M$_{\sun}$ and the stellar birth rate, luminosity functions (LFs) and T$_{eff}$ distributions are…

We present results of a study of very low mass halo stars. Using a sample of proper motion stars identified from plate material taken as part of the first and second Palomar Sky Surveys, we measure the space density, metallicity…

Analysis of initial observations from near-infrared sky surveys has shown that the resulting photometric catalogues, combined with far-red optical data, provide an extremely effective method of finding isolated, very low-temperature objects…