Persistent and occasional: Searching for the variable population of the ZTF/4MOST sky using ZTF Data Release 11
Persistent and occasional: Searching for the variable population of the ZTF/4MOST sky using ZTF Data Release 11
复制标题
持续和偶然:使用 ZTF 数据版本 11 搜索 ZTF/4MOST 天空的可变群体
DOI:
10.1051/0004-6361/202346077
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发表时间:
2023
影响因子:
6.5
通讯作者:
Förster, F.
中科院分区:
文献类型:
--
作者:
Sánchez-Sáez, P.;Arredondo, J.;Bayo, A.;Arévalo, P.;Bauer, F. E.;Cabrera-Vives, G.;Catelan, M.;Coppi, P.;Estévez, P. A.;Förster, F.
AimsWe present a variability-, color-, and morphology-based classifier designed to identify multiple classes of transients and persistently variable and non-variable sources from the Zwicky Transient Facility (ZTF) Data Release 11 (DR11) light curves of extended and point sources. The main motivation to develop this model was to identify active galactic nuclei (AGN) at different redshift ranges to be observed by the 4MOST Chilean AGN/Galaxy Evolution Survey (ChANGES). That being said, it also serves as a more general time-domain astronomy study.MethodsThe model uses nine colors computed from CatWISE and Pan-STARRS1 (PS1), a morphology score from PS1, and 61 single-band variability features computed from the ZTF DR11gandrlight curves. We trained two versions of the model, one for each ZTF band, since ZTF DR11 treats the light curves observed in a particular combination of field, filter, and charge-coupled device (CCD) quadrant independently. We used a hierarchical local classifier per parent node approach-where each node is composed of a balanced random forest model. We adopted a taxonomy with 17 classes: non-variable stars, non-variable galaxies, three transients (SNIa, SN-other, and CV/Nova), five classes of stochastic variables (lowz-AGN, midz-AGN, highz-AGN, Blazar, and YSO), and seven classes of periodic variables (LPV, EA, EB/EW, DSCT, RRL, CEP, and Periodic-other).ResultsThe macro-averaged precision, recall, and F1-score are 0.61, 0.75, and 0.62 for theg-band model, and 0.60, 0.74, and 0.61, for ther-band model. When grouping the four AGN classes (lowz-AGN, midz-AGN, highz-AGN, and Blazar) into one single class, its precision-recall, and F1-score are 1.00, 0.95, and 0.97, respectively, for both thegandrbands. This demonstrates the good performance of the model in classifying AGN candidates. We applied the model to all the sources in the ZTF/4MOST overlapping sky (−28 ≤ Dec ≤ 8.5), avoiding ZTF fields that cover the Galactic bulge (|gal_b| ≤ 9 andgal_l≤ 50). This area includes 86 576 577 light curves in thegband and 140 409 824 in therband with 20 or more observations and with an average magnitude in the corresponding band lower than 20.5. Only 0.73% of theg-band light curves and 2.62% of ther-band light curves were classified as stochastic, periodic, or transient with high probability (Pinit≥ 0.9). Even though the metrics obtained for the two models are similar, we find that, in general, more reliable results are obtained when using theg-band model. With it, we identified 384 242 AGN candidates (including low-, mid-, and high-redshift AGN and Blazars), 287 156 of which havePinit≥ 0.9.
影响因子:
2.4
作者:
Azad Naik;H. Rangwala
通讯作者:
H. Rangwala
DOI:
10.31645/2013.11.2.3
发表时间:
2013
期刊:
Journal of Independent Studies and Research Computing
影响因子:
--
作者:
Adarsh Khalique;Rahim Hasnani
通讯作者:
Rahim Hasnani