MEASUREMENT OF 21 cm BRIGHTNESS FLUCTUATIONS AT z ∼ 0.8 IN CROSS-CORRELATION
MEASUREMENT OF 21 cm BRIGHTNESS FLUCTUATIONS AT z ∼ 0.8 IN CROSS-CORRELATION
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DOI：
10.1088/2041-8205/763/1/l20
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发表时间：
2012-08
期刊：
影响因子：
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通讯作者：
K. Masui;E. Switzer;E. Switzer;N. Banavar;K. Bandura;C. Blake;L.-M. Calin;Tzu-Ching Chang;Xiaodian Chen;Xiaodian Chen;Yin-Jie Li;Yu-Wei Liao;A. Natarajan;Ue-Li Pen;J. Peterson;J. Shaw;T. Voytek
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文献类型：
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作者：
K. Masui;E. Switzer;E. Switzer;N. Banavar;K. Bandura;C. Blake;L.-M. Calin;Tzu-Ching Chang;Xiaodian Chen;Xiaodian Chen;Yin-Jie Li;Yu-Wei Liao;A. Natarajan;Ue-Li Pen;J. Peterson;J. Shaw;T. Voytek
在这封信中，在绿岸望远镜上获得的21厘米的强度图与WiggleZ暗能量调查中星系追踪到的大尺度结构相互关联。数据跨越总计∼41°的两个场的红移范围0.6z；lt；1。平方。以及190小时的无线电集成时间。相互关联约束ΩH ibH ir=[0.4 3±0.0 7(统计)±0.0 4(sy.)]×10−3，其中Ωhi是中性氢(HI)组分，r是星系-氢关联系数，bhi是HI偏置参数.这是在具有挑战性的红移范围内对中性氢密度波动的最精确限制。我们的测量改进了之前在z∼0.8时的21厘米互相关，无论是在精度上还是在探测的尺度范围内都是如此。
In this Letter, 21 cm intensity maps acquired at the Green Bank Telescope are cross-correlated with large-scale structure traced by galaxies in the WiggleZ Dark Energy Survey. The data span the redshift range 0.6 < z < 1 over two fields totaling ∼41 deg. sq. and 190 hr of radio integration time. The cross-correlation constrains ΩH IbH Ir = [0.43 ± 0.07(stat.) ± 0.04(sys.)] × 10−3, where ΩH I is the neutral hydrogen (H i) fraction, r is the galaxy–hydrogen correlation coefficient, and bH I is the H i bias parameter. This is the most precise constraint on neutral hydrogen density fluctuations in a challenging redshift range. Our measurement improves the previous 21 cm cross-correlation at z ∼ 0.8 both in its precision and in the range of scales probed.