PANORAMIC SURVEY OF Lyα EMITTERS AT z = 3.1
PANORAMIC SURVEY OF Lyα EMITTERS AT z = 3.1
复制标题
DOI：
10.1088/0004-6256/143/4/79
复制
发表时间：
2012-02
期刊：
影响因子：
--
通讯作者：
T. Yamada;Y. Nakamura;Y. Matsuda;T. Hayashino;R. Yamauchi;N. Morimoto;K. Kousai;M. Umemura
中科院分区：
文献类型：
--
作者：
T. Yamada;Y. Nakamura;Y. Matsuda;T. Hayashino;R. Yamauchi;N. Morimoto;K. Kousai;M. Umemura
我们给出了在SSA22场中围绕恒星形成星系高密度区（z = 3.09）的1.38度2区域内z = 3.1的Lyα发射在线天体的广泛窄带巡天结果，以及在三个分离的一般空白场的1.04度2区域内。在2161个Lyα发射体中，SSA22场中有1394个，普通场中有767个，在窄带AB等极限为25.73处，对应于线通量≈1.8 × 10−17 erg s−1 cm−2或在z = 3.1处的光度≈1.5 × 1042 erg s−1，高于观测到的等效宽度阈值≈190 Å。在阈值以上的一般场中，在z = 3.1处发射体的平均表面数密度为0.20±0.01 arcmin−2。在z = 3.09处的SSA22高密度区，其峰值局部密度是平均值的6倍，是整个调查区域中最突出的突出结构，被确定为一个强大的“原星团”。我们还比较了包含原星系团的100和700 arcmin2区域的超密度与宇宙学模拟中预期的暗物质波动以及模型星系的超密度。我们发现，在相应的体积中，当z = 3.1时，过量密度的峰高分别是预期标准差的8-10倍和3-4倍。我们得出结论，在SSA22场中，z = 3.09处的结构是一个非常显著且罕见的密度峰，其规模约为60 Mpc。
We present the results of the extensive narrowband survey of Lyα emission-line objects at z = 3.1 in the 1.38 deg2 area surrounding the high-density region of star-forming galaxies at z = 3.09 in the SSA22 field, as well as in the 1.04 deg2 area of the three separated general blank fields. In total, of 2161 Lyα emitters, there are 1394 in the SSA22 fields and 767 in the general fields detected at the narrowband AB magnitude limit of 25.73, which corresponds to the line flux of ≈1.8 × 10−17 erg s−1 cm−2 or the luminosity of ≈1.5 × 1042 erg s−1 at z = 3.1, above the observed equivalent-width threshold, ≈190 Å. The average surface number density of the emitters at z = 3.1 in the general fields above the thresholds is 0.20 ± 0.01 arcmin−2. The SSA22 high-density region at z = 3.09, whose peak local density is six times that of the average, is found to be the most prominent outstanding structure in the whole surveyed area and is firmly identified as a robust “protocluster.” We also compared the overdensity of the 100 arcmin2 and 700 arcmin2 areas which contain the protocluster with the expected fluctuation of the dark matter as well as those of the model galaxies in cosmological simulations. We found that the peak height values of the overdensity are 8–10 and 3–4 times the expected standard deviations for the counts of Lyα emitters at z = 3.1 in the corresponding volume, respectively. We conclude that the structure at z = 3.09 in the SSA22 field is a very significant and rare density peak up to the scale of ≈60 Mpc.