PAU 巡天与 Euclid：利用多任务学习改进宽带测光红移
天体物理仪器与方法
2023-03-22 v2 宇宙学与河外天体物理
星系天体物理
摘要
当前和未来的成像巡天需要为数百万星系估计测光红移（photo-z）。提升 photo-z 质量是一项重大挑战，但对于推进我们对宇宙学的理解必不可少。在本文中，我们探索了如何利用窄带测光数据与大型成像巡天之间的协同作用来改进宽带测光红移。我们使用多任务学习（MTL）网络，通过同时从宽带测光预测宽带 photo-z 和窄带测光来改进宽带 photo-z 估计。窄带测光仅在训练场中需要，这也使得宽场中无窄带测光的星系能获得更好的 photo-z 预测。该技术在 COSMOS 场中利用加速宇宙物理巡天（PAUS）的数据进行了测试。我们发现，与基线网络相比，该方法预测的 photo-z 在星等 i_{AB} < 23 范围内精度提高 13%；异常值率也降低 40%。此外，MTL 降低了高红移星系的 photo-z 偏差，改善了 z>1 层析红移箱的红移分布。将该技术应用于更深样本对 \Euclid 或 LSST 等未来巡天至关重要。对于模拟数据，在 i_{AB} <23 的样本上训练，该方法使所有 i_{AB}<25 星系的 photo-z 散度降低 16%。我们还研究了利用 PAUS 高精度 photo-z 以测光星系扩展训练样本的效果，其在 COSMOS 场中将 photo-z 散度降低 20%。
引用
@article{arxiv.2209.10161,
title = {The PAU Survey & Euclid: Improving broad-band photometric redshifts with multi-task learning},
author = {L. Cabayol and M. Eriksen and J. Carretero and R. Casas and F. J. Castander and E. Fernández and J. Garcia-Bellido and E. Gaztanaga and H. Hildebrandt and H. Hoekstra and B. Joachimi and R. Miquel and C. Padilla and A. Pocino and E. Sanchez and S. Serrano and I. Sevilla and M. Siudek and P. Tallada-Crespí and N. Aghanim and A. Amara and N. Auricchio and M. Baldi and R. Bender and D. Bonino and E. Branchini and M. Brescia and J. Brinchmann and S. Camera and V. Capobianco and C. Carbone and M. Castellano and S. Cavuoti and A. Cimatti and R. Cledassou and G. Congedo and C. J. Conselice and L. Conversi and Y. Copin and L. Corcione and F. Courbin and M. Cropper and A. Da Silva and H. Degaudenzi and M. Douspis and F. Dubath and C. A. J. Duncan and X. Dupac and S. Dusini and S. Farrens and P. Fosalba and M. Frailis and E. Franceschi and P. Franzetti and B. Garilli and W. Gillard and B. Gillis and C. Giocoli and A. Grazian and F. Grupp and S. V. H. Haugan and W. Holmes and F. Hormuth and A. Hornstrup and P. Hudelot and K. Jahnke and M. Kümme and S. Kermiche and A. Kiessling and M. Kilbinger and R. Kohley and H. Kurki-Suonio and S. Ligori and P. B. Lilje and I. Lloro and E. Maiorano and O. Mansutti and O. Marggraf and K. Markovic and F. Marulli and R. Massey and M. Meneghetti and E. Merlin and G. Meylan and M. Moresco and L. Moscardini and E. Munari and R. Nakajima and S. M. Niemi and S. Paltani and F. Pasian and K. Pedersen and V. Pettorino and G. Polenta and M. Poncet and L. Popa and L. Pozzetti and F. Raison and R. Rebolo and J. Rhodes and G. Riccio and C. Rosset and E. Rossetti and R. Saglia and B. Sartoris and P. Schneider and A. Secroun and G. Seide and C. Sirignano and G. Sirri and L. Stanco and A. N. Taylor and I. Tereno and R. Toledo-Moreo and F. Torradeflot and I. Tutusaus and E. Valentijn and L. Valenziano and Y. Wang and J. Weller and G. Zamorani and J. Zoubian and S. Andreon and S. Mei and V. Scottez and A. Tramacere},
journal= {arXiv preprint arXiv:2209.10161},
year = {2023}
}
备注
20 pages, 16 figures