Photometric brown-dwarf classification - I. A method to identify and accurately classify large samples of brown dwarfs without spectroscopy
Photometric brown-dwarf classification - I. A method to identify and accurately classify large samples of brown dwarfs without spectroscopy
复制标题
光度棕矮星分类一、一种无需光谱即可识别并准确分类棕矮星大样本的方法
DOI：
10.1051/0004-6361/201424570
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发表时间：
2014
影响因子：
6.5
通讯作者：
P. Hewett
中科院分区：
文献类型：
--
作者：
N. Skrzypek;S. Warren;J. Faherty;D. Mortlock;A. Burgasser;P. Hewett
目标。我们提出了一种仅用光度学就能识别和准确分类L矮星和T矮星到标准光谱分类系统的方法--照相法。这使得能够高效地创建这些对象的大而深的均匀样本，而不需要光谱分析。方法：研究方法。通过结合SDSS、UKIDSS LAS和WISE数据，我们创建了8个波段的测光点源目录，范围从0.75微米到4.6微米，从3344°2的区域中挑选出来。然后，通过与类星体、恒星和棕矮星的模板颜色进行比较，对13.0 0.8的源进行了分类。光谱类型L0至T8的L模板和T模板是通过利用光谱分类识别先前已知源并拟合色和光谱类型之间的多项式关系而创建的。结果。在调查区域和震级范围内已知的192颗光度测量可靠的L矮星和T矮星中，有189颗是通过我们的选择和分类方法恢复的。我们已经通过创建合成目录和考虑不确定因素，从外部、光谱和内部两个方面量化了分类方法的准确性。我们发现，当亮度大于J=17.5时，光学型分类对一个光谱亚型是准确的，因此与光谱分类具有竞争性。得到的1,157颗L和T矮星的星表将以配文的形式给出。
Aims. We present a method, named photo-type, to identify and accurately classify L and T dwarfs onto the standard spectral classification system using photometry alone. This enables the creation of large and deep homogeneous samples of these objects efficiently, without the need for spectroscopy. Methods. We created a catalogue of point sources with photometry in 8 bands, ranging from 0.75 to 4.6 microns, selected from an area of 3344 deg^2, by combining SDSS, UKIDSS LAS, and WISE data. Sources with 13.0 0.8, were then classified by comparison against template colours of quasars, stars, and brown dwarfs. The L and T templates, spectral types L0 to T8, were created by identifying previously known sources with spectroscopic classifications, and fitting polynomial relations between colour and spectral type. Results. Of the 192 known L and T dwarfs with reliable photometry in the surveyed area and magnitude range, 189 are recovered by our selection and classification method. We have quantified the accuracy of the classification method both externally, with spectroscopy, and internally, by creating synthetic catalogues and accounting for the uncertainties. We find that, brighter than J = 17.5, photo-type classifications are accurate to one spectral sub-type, and are therefore competitive with spectroscopic classifications. The resultant catalogue of 1157 L and T dwarfs will be presented in a companion paper.