First Results from the Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) Survey: Cosmological Reionization at z similar to 7
文献类型:期刊论文
作者 | Zheng, Zhen-Ya; Wang, Junxian; Rhoads, James; Infante, Leopoldo; Malhotra, Sangeeta; Hu, Weida; Walker, Alistair R.; Jiang, Linhua; Jiang, Chunyan; Hibon, Pascale |
刊名 | ASTROPHYSICAL JOURNAL LETTERS
![]() |
出版日期 | 2017 |
卷号 | 842期号:2页码:L22- |
英文摘要 | We present the first results from the ongoing Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) project, which is the largest narrowband survey for z similar to 7 galaxies to date. Using a specially built narrowband filter NB964 for the superb large-area Dark Energy Camera (DECam) on the NOAO/CTIO 4 m Blanco telescope, LAGER has collected 34 hr NB964 narrowband imaging data in the 3 deg(2) COSMOS field. We have identified 23 Ly alpha Emitter candidates at z = 6.9 in the central 2-deg(2) region, where DECam and public COSMOS multi-band images exist. The resulting luminosity function (LF) can be described as a Schechter function modified by a significant excess at the bright end (four galaxies with L-Ly alpha similar to 10(43.4 +/- 0.2) erg s(-1)). The number density at L-Ly alpha similar to 10(43.4 +/- 0.2) erg s(-1) is little changed from z = 6.6, while at fainter L-Ly alpha it is substantially reduced. Overall, we see a fourfold reduction in Ly alpha luminosity density from z = 5.7 to z = 6.9. Combined with a more modest evolution of the continuum UV luminosity density, this suggests a factor of similar to 3 suppression of Ly alpha by radiative transfer through the z similar to 7 intergalactic medium (IGM). It indicates an IGM neutral fraction of x(HI) similar to 0.4-0.6 (assuming Ly alpha velocity offsets of 100-200 km s(-1)). The changing shape of the Ly alpha LF between z less than or similar to 6.6 and z = 6.9 supports the hypothesis of ionized bubbles in a patchy reionization at z similar to 7. |
语种 | 英语 |
源URL | [http://libir.pmo.ac.cn/handle/332002/17399] ![]() |
专题 | 中国科学院紫金山天文台 |
推荐引用方式 GB/T 7714 | Zheng, Zhen-Ya,Wang, Junxian,Rhoads, James,et al. First Results from the Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) Survey: Cosmological Reionization at z similar to 7[J]. ASTROPHYSICAL JOURNAL LETTERS,2017,842(2):L22-. |
APA | Zheng, Zhen-Ya.,Wang, Junxian.,Rhoads, James.,Infante, Leopoldo.,Malhotra, Sangeeta.,...&Felipe Barrientos, L..(2017).First Results from the Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) Survey: Cosmological Reionization at z similar to 7.ASTROPHYSICAL JOURNAL LETTERS,842(2),L22-. |
MLA | Zheng, Zhen-Ya,et al."First Results from the Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) Survey: Cosmological Reionization at z similar to 7".ASTROPHYSICAL JOURNAL LETTERS 842.2(2017):L22-. |
入库方式: OAI收割
来源:紫金山天文台
浏览0
下载0
收藏0
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。