Emission-Line Galaxies from the NICMOS/Hubble Space Telescope Grism Parallel Survey
Emission-Line Galaxies from the NICMOS/Hubble Space Telescope Grism Parallel Survey
复制标题
来自 NICMOS/哈勃太空望远镜棱镜平行巡天的发射线星系
DOI：
10.1086/307491
复制
发表时间：
1999
期刊：
影响因子：
--
通讯作者：
S. Heap
中科院分区：
文献类型：
--
作者：
P. McCarthy;Lin Yan;W. Freudling;H. Teplitz;E. Malumuth;R. Weymann;M. Malkan;R. Fosbury;J. Gardner;L. Storrie;R. Thompson;Robert E. Williams;S. Heap
我们展示了在哈勃太空望远镜 (HST) 上的近红外相机和多目标光谱仪 (NICMOS) 上使用无缝 G141（λc = 1.5 μm，Δλ = 0.8 μm）棱镜进行随机场调查的第一个结果。在银河系中纬度和高纬度地区观测到大约 64 arcmin2。每个场中的 3 σ 限制线和连续通量分别从 7.5 × 10-17 到 1 × 10-17 ergs cm-2 s-1 变化，并且从 H = 20 到 22 变化。我们在 4 像素孔径内的中值和面积加权 3 σ 限制线通量在 4.1 × 10-17 ergs cm-2 s-1 处几乎相同，并且比地面最深窄带成像勘测深 60%。我们已经识别了 33 个发射线物体，并得出了它们观测到的波长、通量和等效宽度。我们认为最可能的线识别是 Hα，并且探测的红移范围是从 0.75 到 1.9。 2 σ 静止框架等效宽度限制范围为 9 至 130 Å，平均为 40 Å。当 q0 = 0.5 时，调查探测有效同移体积为 105 h-350 Mpc3。我们推导的发射线星系在 0.7 < z < 1.9 范围内的共动数密度为 3.3 × 10-4 h350 Mpc-3，与 z ~ 3 处的明亮莱曼断裂天体非常相似。检测到发射线的天体的中值 F160W 星等为 20.4（织女星尺度），中值 Hα 光度为 2.7 × 1042 ergs s-1。隐含的恒星形成速率范围从 1 到 324 M☉ yr-1，平均 [N II] λλ6583, 6548 校正速率为 21 M☉ yr-1，H0 = 50 km s-1 Mpc 和 q0 = 0.5（34 M☉ yr-1，q0 = 0.1）。
We present the first results of a survey of random fields with the slitless G141 (λc = 1.5 μm, Δλ = 0.8 μm) grism on the near-IR camera and multiobject spectrometer (NICMOS) on board the Hubble Space Telescope (HST). Approximately 64 arcmin2 have been observed at intermediate and high Galactic latitudes. The 3 σ limiting line and continuum fluxes in each field vary from 7.5 × 10-17 to 1 × 10-17 ergs cm-2 s-1, and from H = 20 to 22, respectively. Our median and area-weighted 3 σ limiting line fluxes within a 4 pixel aperture are nearly identical at 4.1 × 10-17 ergs cm-2 s-1 and are 60% deeper than the deepest narrowband imaging surveys from the ground. We have identified 33 emission-line objects and derive their observed wavelengths, fluxes, and equivalent widths. We argue that the most likely line identification is Hα and that the redshift range probed is from 0.75 to 1.9. The 2 σ rest-frame equivalent width limits range from 9 to 130 Å, with an average of 40 Å. The survey probes an effective comoving volume of 105 h-350 Mpc3 for q0 = 0.5. Our derived comoving number density of emission-line galaxies in the range 0.7 < z < 1.9 is 3.3 × 10-4 h350 Mpc-3, very similar to that of the bright Lyman break objects at z ~ 3. The objects with detected emission lines have a median F160W magnitude of 20.4 (Vega scale) and a median Hα luminosity of 2.7 × 1042 ergs s-1. The implied star formation rates range from 1 to 324 M☉ yr-1, with an average [N II] λλ6583, 6548 corrected rate of 21 M☉ yr-1 for H0 = 50 km s-1 Mpc and q0 = 0.5 (34 M☉ yr-1 for q0 = 0.1).