超新星（SN）率的确定不仅基于探测到的事件数量，而且还基于母星系群的属性。这是一系列论文中的第一篇，旨在通过利用近红外（NIR）数据的联合分析，从一组五次SN调查中获得新的、精确的SN率。我们描述的3838个星系的SNe事件，包括新确定的形态和它们的DENIS和POSS-II/UKST I，2 MASS和DENIS J和Ks和2 MASS H的星等监测的属性。我们比较了2 MASS，DENIS和POSS-II/UKST IJK星等，以找到可能的系统光度变化的测量。DENIS和POSS-II/UKST I波段的星等显示出很大的差异（平均绝对差为0.4等），这主要是由于两种仪器的光谱响应不同，POSS-II和UKST照相底片的光度校准中存在很大的不确定性，这是一个重要的贡献（0.33等均方根）。在其他波段，星系的极限近红外星等、形态和倾角是影响星系光度测定的主要因素。尽管如此，除了少数几个星系显示出很大的差异外，在任何一对近红外星等测量之间都没有发现显着的系统差异。这使我们能够将DENIS和2 MASS数据结合起来用于J和Ks滤波器。
英文摘要：
The determination of the supernova (SN) rate is based not only on the number of detected events, but also on the properties of the parent galaxy population. This is the first paper of a series aimed at obtaining new, refined, SN rates from a set of five SN surveys, by making use of a joint analysis of near-infrared (NIR) data. We describe the properties of the 3838 galaxies that were monitored for SNe events, including newly determined morphologies and their DENIS and POSS-II/UKST I, 2MASS and DENIS J and Ks and 2MASS H magnitudes. We have compared 2MASS, DENIS and POSS-II/UKST IJK magnitudes in order to find possible systematic photometric shifts in the measurements. The DENIS and POSS-II/UKST I band magnitudes show large discrepancies (mean absolute difference of 0.4 mag), mostly due to different spectral responses of the two instruments, with an important contribution (0.33 mag rms) from the large uncertainties in the photometric calibration of the POSS-II and UKST photographic plates. In the other wavebands, the limiting near infrared magnitude, morphology and inclination of the galaxies are the most influential factors which affect the determination of photometry of the galaxies. Nevertheless, no significant systematic differences have been found between of any pair of NIR magnitude measurements, except for a few percent of galaxies showing large discrepancies. This allows us to combine DENIS and 2MASS data for the J and Ks filters.
Recent observations using several different telescopes and sky surveys showed patterns of asymmetry in the distribution of galaxies by their spin directions as observed from Earth. These studies were done with data imaged from the Northern hemisphere, showing excellent agreement between different telescopes and different analysis methods. Here, data from the DESI Legacy Survey was used. The initial dataset contains $\sim2.2\cdot10^7$ galaxy images, reduced to $\sim8.1\cdot10^5$ galaxies annotated by their spin direction using a symmetric algorithm. That makes it not just the first analysis of …
We present a broadband map of polarized diffuse emission at 167-198 MHz developed from data from the Murchison Widefield Array (MWA). The map is designed to improve visibility simulation and precision calibration for 21 cm Epoch of Reionization (EoR) experiments. It covers a large swath - 11,000 sq. deg. - of the Southern Hemisphere sky in all four Stokes parameters and captures emission on angular scales of 1 to 9 degrees. The band-averaged diffuse structure is predominantly unpolarized but has significant linearly polarized structure near RA = 0 h. We evaluate the accuracy of the map by comb…
The Sagittarius Streams in the Southern Galactic Hemisphere
Sloan Digital Sky Survey Data Release 8分析了南银河半球人马座流的结构。与人马座潮汐轨道平行，但距离约10度，有另一个更暗，更贫金属流。我们提供的证据表明，这两个流遵循类似的距离梯度，但有不同的形态学特性和恒星星族。较亮的星流较宽，包含更多富含金属的恒星，并且与较暗的星流相比，具有更丰富的颜色-星等图，有多个转折点和一个突出的红色团块。根据结构性质和恒星星族混合，流的配置类似于北方的“分叉”。在南银河帽区域，有来自鲸鱼座流的潮汐碎片重叠，它穿过人马座流。使用光度和光谱数据，我们表明，蓝色离散人口主要属于人马座和蓝色水平分支恒星主要属于鲸鱼座流在这个混乱的位置在晕。
The DESI Legacy Survey is a digital sky survey with a large footprint compared to other Earth-based surveys, covering both the Northern and Southern hemispheres. This paper shows the distribution of the spin directions of spiral galaxies imaged by DESI Legacy Survey. A simple analysis of dividing nearly 1.3$\cdot10^6$ spiral galaxies into two hemispheres shows a higher number of galaxies spinning counterclockwise in the Northern hemisphere, and a higher number of galaxies spinning clockwise in the Southern hemisphere. That distribution is consistent with previous observations, but uses a far l…
This paper provides a catalogue of stars, quasars, and galaxies for the Southern Photometric Local Universe Survey Data Release 2 (S-PLUS DR2) in the Stripe 82 region. We show that a 12-band filter system (5 Sloan-like and 7 narrow bands) allows better performance for object classification than the usual analysis based solely on broad bands (regardless of infrared information). Moreover, we show that our classification is robust against missing values. Using spectroscopically confirmed sources retrieved from the Sloan Digital Sky Survey DR16 and DR14Q, we train a random forest classifier with …
The Galactic center excess (GCE) remains one of the most intriguing discoveries from the Fermi Large Area Telescope (LAT) observations. We revisit the characteristics of the GCE by first producing a new set of high-resolution galactic diffuse gamma-ray emission templates, which are ultimately due to cosmic-ray interactions with the interstellar medium. Using multi-messenger observations we constrain the properties of the galactic diffuse emission. The broad properties of the GCE that we find in this work are qualitatively unchanged despite the introduction of this new set of templates, though …
