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QUaD银道巡天1:漫发射的地图和分析

The QUaD Galactic Plane Survey 1: Maps And Analysis of Diffuse Emission

T. Culverhouse, P. Ade, J. Bock, M. Bowden, M. L. Brown, G. Cahill, P. G. Castro, S. Church, R. Friedman, K. Ganga, W. K. Gear, S. Gupta, J. Hinderks, J. Kovac,… 展开作者

T. Culverhouse, P. Ade, J. Bock, M. Bowden, M. L. Brown, G. Cahill, P. G. Castro, S. Church, R. Friedman, K. Ganga, W. K. Gear, S. Gupta, J. Hinderks, J. Kovac, A. E. Lange, E. Leitch, S. J. Melhuish, Y. Memari, J. A. Murphy, A. Orlando, R. Schwarz, C. O' Sullivan, L. Piccirillo, C. Pryke, N. Rajguru, B. Rusholme, A. N. Taylor, K. L. Thompson, A. H. Turner, E. Y. S. Wu, M. Zemcov

摘要:

我们提出了一个调查~800平方度的银河系平面观察QUaD望远镜。调查的主要产品是100和150 GHz的斯托克斯I、Q和U参数图,空间分辨率分别为5和3.5角分。覆盖了两个区域,分别跨越银经l约245-295度和315-5度,银纬b约-4<b<+4度。在0.02平方度像素尺寸下,I在100 GHz和150 GHz下的中值灵敏度分别为74和107 kJy/sr,Q和U的中值灵敏度分别为98和120 kJy/sr。在总强度中,我们发现|b| <1度的平均光谱指数为2.35+/-0.01(stat)+/-0.02(sys),表明除了热尘埃之外的发射成分。出版的灰尘,同步加速器和自由的模型的比较意味着在100 GHz的QUaD波段的过量发射,而更好的协议是在150 GHz。当比较QUaD 100 GHz数据与WMAP 5年W波段时,观察到较小的过量;在这种情况下,过量可能是由于QUaD的带宽更宽。结合QUaD和WMAP的数据,一个两分量的光谱拟合的内银道面(|b| <1度)产生的平均光谱指数为-0.32 +/- 0.03和2.84 +/- 0.03;前者被解释为同步加速器的光谱指数的组合,自由和尘埃,而第二个主要是归因于热尘埃连续。在相同的银河纬度范围内,偏振数据显示出与预期的银河磁场方向垂直的高度对准,并且在100 GHz和150 GHz处分别显示出1.38+/-0.08(stat)+/-0.1(sys)%和1.70 +/-0.06(stat)+/-0.1(sys)%的平均偏振分数。我们发现QUaD 100 GHz和WMAP W波段之间的极化分数一致,后者为1.1 +/-0.4%。

英文摘要:

We present a survey of ~800 square degrees of the galactic plane observed with the QUaD telescope. The primary product of the survey are maps of Stokes I, Q and U parameters at 100 and 150 GHz, with spatial resolution 5 and 3.5 arcminutes respectively. Two regions are covered, spanning approximately 245-295 and 315-5 degrees in galactic longitude l, and -4<b<+4 degrees in galactic latitude b. At 0.02 degree square pixel size, the median sensitivity is 74 and 107 kJy/sr at 100 GHz and 150 GHz respectively in I, and 98 and 120 kJy/sr for Q and U. In total intensity, we find an average spectral index of 2.35+/-0.01 (stat) +/- 0.02 (sys) for |b|<1 degree, indicative of emission components other than thermal dust. A comparison to published dust, synchrotron and free-free models implies an excess of emission in the 100 GHz QUaD band, while better agreement is found at 150 GHz. A smaller excess is observed when comparing QUaD 100 GHz data to WMAP 5-year W band; in this case the excess is likely due to the wider bandwidth of QUaD. Combining the QUaD and WMAP data, a two-component spectral fit to the inner galactic plane (|b|<1 degree) yields mean spectral indices of -0.32 +/- 0.03 and 2.84 +/- 0.03; the former is interpreted as a combination of the spectral indices of synchrotron, free-free and dust, while the second is attributed largely to the thermal dust continuum. In the same galactic latitude range, the polarization data show a high degree of alignment perpendicular to the expected galactic magnetic field direction, and exhibit mean polarization fraction 1.38+/-0.08 (stat) +/-0.1 (sys) % at 100 GHz and 1.70 +/- 0.06 (stat) +/- 0.1 (sys) % at 150GHz. We find agreement in polarization fraction between QUaD 100 GHz and WMAP W band, the latter giving 1.1 +/- 0.4 %.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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