论文标题
Pan-Starrs1调查的光度红移
Photometric redshifts for the Pan-STARRS1 survey
论文作者
论文摘要
我们提出了一种强大的方法，可以使用Pan-Starrs1光度数据估算星系的红移。我们的方法是对贝克等人提出的一种改编。 （2016年）对于SDSS数据版本12。它使用了一组2313724星系的训练集，从SDSS获得光谱红移，并从Pan-Starrs1 Data Release 2调查中获得了幅度和颜色。然后，通过在5维大小和色彩空间中的局部线性回归来估计星系的光度红移。我们的方法达到了$ \叠加的平均偏差{Δz_{\ rm norm}} = - 2.01 \ 2.01 \ times 10^{ - 4} $，$σ（Δz_{\ rm norm}）的标准偏差= 0.0298 $，以及$ p_o = 4.32 $ $ p_o = 4.32 $ $ p_o = 4.32 $ $ p _32 $ nert。即使每种Pan-Starrs1颜色与光谱红移之间的关系比SDSS颜色吵架，但通过我们的方法获得的结果非常接近SDSS数据所产生的结果。所提出的方法具有额外的优势，即允许在较大的天空（$ \ sim 3/4 $ vs $ \ sim 1/3 $）上估算光度红移。培训集和实施此方法的代码可在www.testaddress.com上公开获得。
We present a robust method to estimate the redshift of galaxies using Pan-STARRS1 photometric data. Our method is an adaptation of the one proposed by Beck et al. (2016) for the SDSS Data Release 12. It uses a training set of 2313724 galaxies for which the spectroscopic redshift is obtained from SDSS, and magnitudes and colours are obtained from the Pan-STARRS1 Data Release 2 survey. The photometric redshift of a galaxy is then estimated by means of a local linear regression in a 5-dimensional magnitude and colour space. Our method achieves an average bias of $\overline{Δz_{\rm norm}}=-2.01 \times 10^{-4}$, a standard deviation of $σ(Δz_{\rm norm})=0.0298$, and an outlier rate of $P_o=4.32\%$ when cross-validating on the training set. Even though the relation between each of the Pan-STARRS1 colours and the spectroscopic redshifts is noisier than for SDSS colours, the results obtained by our method are very close to those yielded by SDSS data. The proposed method has the additional advantage of allowing the estimation of photometric redshifts on a larger portion of the sky ($\sim 3/4$ vs $\sim 1/3$). The training set and the code implementing this method are publicly available at www.testaddress.com.
