First-generation Science Cases for Ground-based Terahertz Telescopes
Abstract
Ground-based observations at terahertz (THz) frequencies are a newly explorable area of astronomy for the next ten years. We discuss science cases for a first-generation 10-m class THz telescope, focusing on the Greenland Telescope as an example of such a facility. We propose science cases and provide quantitative estimates for each case. The largest advantage of ground-based THz telescopes is their higher angular resolution (~ 4 arcsec for a 10-m dish), as compared to space or airborne THz telescopes. Thus, high-resolution mapping is an important scientific argument. In particular, we can isolate zones of interest for Galactic and extragalactic star-forming regions. The THz windows are suitable for observations of high-excitation CO lines and [N II] 205 um lines, which are scientifically relevant tracers of star formation and stellar feedback. Those lines are the brightest lines in the THz windows, so that they are suitable for the initiation of ground-based THz observations. THz polarization of star-forming regions can also be explored since it traces the dust population contributing to the THz spectral peak. For survey-type observations, we focus on ``sub-THz'' extragalactic surveys, whose uniqueness is to detect galaxies at redshifts z ~ 1--2, where the dust emission per comoving volume is the largest in the history of the Universe. Finally we explore possibilities of flexible time scheduling, which enables us to monitor active galactic nuclei, and to target gamma-ray burst afterglows. For these objects, THz and submillimeter wavelength ranges have not yet been explored.
Cite
@article{arxiv.1511.00839,
title = {First-generation Science Cases for Ground-based Terahertz Telescopes},
author = {Hiroyuki Hirashita and Patrick M. Koch and Satoki Matsushita and Shigehisa Takakuwa and Masanori Nakamura and Keiichi Asada and Hauyu Baobab Liu and Yuji Urata and Ming-Jye Wang and Wei-Hao Wang and Satoko Takahashi and Ya-Wen Tang and Hsian-Hong Chang and Kuiyun Huang and Oscar Morata and Masaaki Otsuka and Kai-Yang Lin and An-Li Tsai and Yen-Ting Lin and Sundar Srinivasan and Pierre Martin-Cocher and Hung-Yi Pu and Francisca Kemper and Nimesh Patel and Paul Grimes and Yau-De Huang and Chih-Chiang Han and Yen-Ru Huang and Hiroaki Nishioka and Lupin Chun-Che Lin and Qizhou Zhang and Eric Keto and Roberto Burgos and Ming-Tang Chen and Makoto Inoue and Paul T. P. Ho},
journal= {arXiv preprint arXiv:1511.00839},
year = {2015}
}
Comments
39 pages, 17 figures, accepted for publication in PASJ (as a review paper)