The color - stellar mass-to-light ratio relation (CMLR) is a widely accepted tool to estimate the stellar mass (M*) of a galaxy. However, an individual CMLR tends to give distinct M* for a same galaxy when it is applied in different bands. Examining five representative CMLRs from literature, we find that the difference in M* predicted in different bands from optical to near-infrared by a CMLR is 0.1-0.3 dex. Therefore, based on a sample of low surface brightness galaxies (LSBG) that covers a wide range of color and luminosity, we re-calibrated each original CMLR in r, i, z, J, H, and K bands to give internally self-consistent M* for a same galaxy. The g-r is the primary color indicator in the re-calibrated relations which show little dependenceon red (r - z) or near-infrared (J - K) colors.Additionally, the external discrepancies in the originally predicted stellar mass-to-light ratio (M*/L) by the five independent CMLRs have been greatly reduced after re-calibration, especially in near-infrared bands, implying that the near-infrared luminosities are more robust to predict M*/L. For each CMLR, the re-calibrated relations provided in this work could produce internally self-consistent M* from divergent photometric bands, and are extensions of the re-calibrations from Johnson-Cousin filter system by the pioneering work of McGaugh & Schombert (2014) to SDSS filter system.
I consider a sample of eight pressure-supported low-surface brightness galaxies in terms of Milgrom's modified Newtonian dynamics (MOND). These objects include seven nearby dwarf spheroidal galaxies -- Sextans, Carina, Leo II, Sculptor, Draco, Leo I, Fornax, and the ultra-diffuse galaxy DF44. The objects are modelled as Milgromian isotropic isothermal spheres characterised by two parameters that are constrained by observations: the constant line-of-sight velocity dispersion and the central surface density. The velocity dispersion determines the total mass, and, with the implied mass-to-light r…
Massive disk galaxies with high surface brightness plus low surface brightness stellar disks, hosted by massive dark matter halo -- a TNG50 simulation study
Tata Institute of Fundamental Research（塔塔基础研究所）；Inter-University Centre for Astronomy and Astrophysics（大学间天体物理中心）
We use the low surface brightness galaxy (LSBG) samples created from the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP, 781 galaxies), the Dark Energy Survey (DES, 20977 galaxies), and the Legacy Survey (selected via HI detection in the Arecibo Legacy Fast ALFA Survey, 188 galaxies) to infer the intrinsic shape distribution of the low surface brightness galaxy population. To take into account the effect of the surface brightness cuts employed when constructing LSBG samples, we simultaneously model both the projected ellipticity and the apparent surface brightness in our shape inference. …
The star formation rate in galaxies is well known to correlate with stellar mass (the `star-forming main sequence'). Here we extend this further to explore any additional dependence on galaxy surface brightness, a proxy for stellar mass surface density. We use a large sample of low redshift ($z \leq 0.08$) galaxies from the GAMA survey which have both SED derived star formation rates and photometric bulge-disc decompositions, the latter providing measures of disc surface brightness and disc masses. Using two samples, one of galaxies fitted by a single component with Sérsic index below 2 and on…
The connection between surface brightness and satellite systems for central galaxies through Illustris TNG
Observatorio Astronómico de Córdoba, Universidad Nacional de Córdoba（科尔多瓦天文台，科尔多瓦国立大学）；Instituto de Astronomía Teórica y Experimental, UNC-CONICET（理论与实验天体物理研究所，科尔多瓦国立大学-阿根廷国家科学研究委员会）；Department of Physics and Astronomy, University of California, Riverside（物理学与天文学系，加州大学河滨分校）；Instituto de Astronomía y Física del Espacio, CONICET-UBA（空间天体物理与物理学研究所，阿根廷国家科学研究委员会-布宜诺斯艾利斯大学）；Instituto de Astrofísica, Pontificia Universidad Católica de Chile（天体物理研究所，智利天主教 Pontificia 大学）
Low-surface-brightness galaxies (LSBGs) -- defined as systems that are fainter than the surface-brightness limits of past wide-area surveys -- form the overwhelming majority of galaxies in the dwarf regime (M* < 10^9 MSun). Using NewHorizon, a high-resolution cosmological simulation, we study the origin of LSBGs and explain why LSBGs at similar stellar mass show the large observed spread in surface brightness. New Horizon galaxies populate a well-defined locus in the surface brightness -- stellar mass plane, with a spread of ~3 mag arcsec^-2, in agreement with deep SDSS Stripe data. Galaxies w…
DGSAT: Dwarf Galaxy Survey with Amateur Telescopes II. A catalogue of isolated nearby edge-on disk galaxies and the discovery of new low surface brightness systems
SMUDGes Below the Surface: Clusters Confirm the Diversity of Low-Surface-Brightness Galaxies
Steward Observatory and Department of Astronomy, University of Arizona（亚利桑那大学天体物理观测站和天文学系）；Department of Physics & Astronomy, University of California, Irvine（加州大学尔湾分校物理与天文学系）
本研究通过SMUDGes巡天的44个低表面亮度星系，利用Keck Cosmic Web Imager光谱学发现其普遍存在星团，证实这类星系性质多样，不存在单一形成机制，且星团年龄多样性会影响总晕质量的示踪。
We investigate the formation and properties of low surface brightness galaxies (LSBGs) with $M_{*} > 10^{9.5} \mathrm{M_{\odot}}$ in the EAGLE hydrodynamical cosmological simulation. Galaxy surface brightness depends on a combination of stellar mass surface density and mass-to-light ratio ($M/L$), such that low surface brightness is strongly correlated with both galaxy angular momentum (low surface density) and low specific star formation rate (high $M/L$). This drives most of the other observed correlations between surface brightness and galaxy properties, such as the fact that most LSBGs hav…
Superthin galaxies (STs) are edge-on disc galaxies with strikingly high planar-to-vertical axes ratios of $\sim 10 - 20$ with no bulge component, and central surface brightness in $B$-band $>$ 23 mag arcsec$^{-2}$ comparable to low surface brightness galaxies (LSBs). Although STs and LSBs have similar dynamical, stellar and atomic hydrogen (HI) masses on an average, it is tricky to conclude if they constitute the same galaxy population, given the edge-on and face-on orientations of the STs and the LSBs respectively. We systematically study star formation rate (SFR) in a sample of STs and LSBs …
We perform Lyman-alpha radiative transfer calculations for reproducing Lyman-alpha properties of star-forming galaxies at high redshifts. We model a galaxy as a halo in which the density distributions of Lyman-alpha sources and H I plus dust medium are described with exponential functions. We also consider an outflow of the medium that represents a momentum-driven wind in a gravitational potential well. We successfully reproduce both the spectra and the surface brightness profiles of eight star-forming galaxies at z =3-6 observed with MUSE using this outflowing halo model with Lyman-alpha scat…
The Merger-Driven Formation of Classical Low Surface Brightness Galaxies in Romulus25
Rutgers, The State University of New Jersey（新泽西州立罗格斯大学）；Johns Hopkins University（约翰斯·霍普金斯大学）；Flatiron Institute（平顶山研究所）；University College Cork（科克大学学院）；Williams College（威廉姆斯学院）；SETI Institute（搜寻地外文明研究所）；George Mason University（乔治梅森大学）；University of Washington（华盛顿大学）
We present a catalogue of low surface brightness (LSB) galaxies in the Coma cluster obtained from deep Subaru/Suprime-Cam V and R-band imaging data within a region of $\sim$4 deg$^2$. We increase the number of LSB galaxies presented in Yagi et al. (2016) by a factor of $\sim$3 and report the discovery of 29 new ultra-diffuse galaxies (UDGs). We compile the largest sample of ultra-diffuse galaxies with colours and structural parameters in the Coma cluster. While most UDGs lie along the red-sequence relation of the colour-magnitude diagram, $\sim$5per cent are outside (bluer or redder) the red-s…
A Study of Active Galactic Nuclei in Low Surface Brightness Galaxies with Sloan Digital Sky Survey Spectroscopy
低表面亮度星系（LSBG）中的活动星系核（AGN）在以往的研究中很少受到关注。本文对Impey等人（1996）的APM LSBG样品中的194个LSBG进行了详细的光谱分析，这些样品是由Sloan数字巡天数据发布5（SDSS DR 5）进行光谱观测的。我们精心的光谱分析使我们能够进行，第一次，可靠的光谱分类的基础上，严格的标准发射线诊断图在LSBGs的核活动。恒星形成星系是常见的，在大约52%的LSBG中发现。我们发现，与以前的一些说法相反，含有活动星系核的星系的比例显着低于附近的正常星系的高表面亮度。这与Impey等人（2001年）的研究结果定性一致。这一结果适用于每个形态类型，从Sa到Sc。具有较大的中心恒星速度色散，或较大的物理尺寸的LSBG，往往有更高的机会窝藏AGN。对于三个具有宽发射线的活动星系核，由发射线估算的黑洞质量与已知的正常星系和活动星系核的M- $σ_\ast$关系基本一致。
Low Surface Brightness Galaxies selected from the 40% sky area of the ALFALFA HI survey.I.Sample and statistical properties
低表面亮度（LSB）星系的数量对于理解星系形成和宇宙演化的极端情况至关重要。由于LSB星系大多富含气体（HI），因此α 40-SDSS DR 7样本绝对是在本地宇宙中选择样本的最佳调查组合之一。由于SDSS测光管道系统地高估了星系图像的天空背景，特别是对于发光星系或具有扩展的低表面亮度外围的星系，在本文中，我们首先估计了α 40-SDSS DR 7样本中SDSS图像的天空背景，使用精确的天空相减方法。一旦减去天空背景，我们用Kron椭圆孔径进行表面测光，并为每个星系图像用指数轮廓模型拟合几何参数。基于光度和几何结果，我们进一步计算了每个星系的B波段中心表面亮度，mu_{0}（B），并最终定义了一个由1129个星系组成的LSB星系样本，其中mu_{0}（B）> 22.5 mag arcsec^{-2}，短轴与长轴之比b/a > 0.3。这是一个来自α 40-SDSS DR 7的HI选择的LSB星系样本，它是一个相对无偏的富气盘主导型LSB星系样本，在HI观测和SDSS DR 7测光范围内的光学星等都是完整的。我们对这个LSB星系样品的光学和射电21 cm HI特性进行了分析。此外，我们还对LSB星系的环境进行了统计研究，发现高达92%的LSB星系的邻近星系少于8个，这有力地证明了LSB星系更喜欢居住在低密度环境中。
The low surface brightness galaxies are gas-rich and yet have a low star formation rate, this is a well-known puzzle. The spiral features in these galaxies are weak and difficult to trace, although this aspect has not been studied much. These galaxies are known to be dominated by the dark matter halo from the innermost regions. Here we do a stability analysis for the galactic disc of UGC 7321, a low surface brightness, superthin galaxy, for which the various observational input parameters are available. We show that the disc is stable against local, linear axisymmetric and non-axisymmetric per…
A central question regarding Ultra Diffuse Galaxies (UDGs) is whether they are a separate category to Low Surface Brightness (LSB) galaxies, or just their natural continuation towards low stellar masses. In this letter, we show that the rotation curve of the gas rich UDG AGC 242019 is well fit by a dark matter halo with inner slope that asymptotes to -0.54, and that such fit provides a concentration parameter that matches theoretical expectations. This finding, together with previously works in which shallow inner profiles are derived for UDGs, shows that the structural properties of these gal…
University of Chicago（芝加哥大学）；Kavli Institute for Cosmological Physics（卡夫利宇宙物理研究所）；Fermi National Accelerator Laboratory（费米国家加速器实验室）
Measuring the structural parameters (size, total brightness, light concentration, etc.) of galaxies is a significant first step towards a quantitative description of different galaxy populations. In this work, we demonstrate that a Bayesian Neural Network (BNN) can be used for the inference, with uncertainty quantification, of such morphological parameters from simulated low-surface-brightness galaxy images. Compared to traditional profile-fitting methods, we show that the uncertainties obtained using BNNs are comparable in magnitude, well-calibrated, and the point estimates of the parameters …
