MeerKAT吸收线巡天(MALS)
星系天体物理
2017-08-25 v1
摘要
深度星系巡天表明,宇宙中的全局恒星形成率(SFR)密度在 1 < z < 2 时达到峰值,并随着 z 趋向 0 而急剧下降。然而,对于驱动这种强烈演化的潜在过程,特别是冷原子(~100 K)和分子气体相的演化,目前尚未形成清晰的认识。MALS旨在利用MeerKAT的L波段和UHF波段接收器,在 0 < z < 2 范围内对介入的 HI 21-cm 和 OH 18-cm 吸收线进行最灵敏的(N(HI)>10 cm)、无偏的尘埃搜索。这将提供星系冷原子和分子气体截面演化的可靠测量,并揭示驱动SFR密度急剧演化的过程。从该巡天获得的大样本HI和OH吸收体将(i)对物理学基本常数给出最严格的限制,以及(ii)非常适合通过塞曼分裂或旋转测量合成来探测星系盘内磁场演化。该巡天还将提供无偏的HI和OH吸收体普查,即在 0 < z < 2 期间与强AGN(>10 W Hz)相关的冷气体,并同时进行盲HI和OH发射线巡天以及射电连续谱巡天。在此,我们描述了MALS的巡天设计、观测计划以及将在各个科学主题下解决的科学问题。
引用
@article{arxiv.1708.07371,
title = {The MeerKAT Absorption Line Survey (MALS)},
author = {N. Gupta and R. Srianand and W. Baan and A. Baker and R. Beswick and S. Bhatnagar and D. Bhattacharya and A. Bosma and C. Carilli and M. Cluver and F. Combes and C. Cress and R. Dutta and J. Fynbo and G. Heald and M. Hilton and T. Hussain and M. Jarvis and G. Jozsa and P. Kamphuis and A. Kembhavi and J. Kerp and H. -R. Klöckner and J. Krogager and V. Kulkarni and C. Ledoux and A. Mahabal and T. Mauch and K. Moodley and E. Momjian and R. Morganti and P. Noterdaeme and T. Oosterloo and P. Petitjean and A. Schröder and P. Serra and J. Sievers and K. Spekkens and P. Väisänen and T. van der Hulst and M. Vivek and J. Wang and O. I. Wong and A. R. Zungu},
journal= {arXiv preprint arXiv:1708.07371},
year = {2017}
}
备注
16 pages, 3 figures Accepted for publication, Proceedings of Science, Workshop on "MeerKAT Science: On the Pathway to the SKA", held in Stellenbosch 25-27 May, 2016