Planck 中期结果 X：后发座星系团中热气体的物理学
宇宙学与河外天体物理
2015-03-20 v3
摘要
我们展示了通过 Sunyaev-Zeldovich 效应观测到的后发座星系团 (Coma Cluster) 的 Planck 卫星数据分析结果。Planck 首次能够探测到高达 r ~ 3 X R_500 的 SZ 辐射。我们针对方位角平均数据测试了先前提出的星系团压力分布模型。我们发现 Arnaud 等人的通用压力剖面并不适用于后发座星系团，且他们针对并合系统的压力剖面仅在 r<R_500 时能良好拟合数据：在 r=2XR_500 处，其低估了观测到的 y 剖面约 2 倍。这可能表明在这些较大半径处，要么 i) 星系团的 SZ 辐射受到沿视线方向未分辨 SZ 源的污染，要么 ii) 后发座星系团在 r>R_500 处的压力剖面高于模拟预测的平均压力剖面。Planck 图像显示，在星系团中心以西和东南方向约半度的两个区域，y 剖面存在显著的局部陡化。这些特征与这些半径处存在激波前沿一致，事实上，西部特征此前已在 ROSAT PSPC 拼接图以及射电观测中被注意到。利用从相应扇区提取的 Planck y 剖面，我们发现西部和东南部的压力跃变分别为 4.5+0.4-0.2 和 5.0+1.3-0.1。假设 Rankine-Hugoniot 压力跃变条件，我们推断激波在西侧和东南侧的传播马赫数应分别为 M_w=2.03+0.09-0.04 和 M_se=2.05+0.25-0.02。最后，我们发现 y 信号与射电同步辐射信号在 Mpc 尺度上呈准线性相关，且内禀散射较小。这意味着要么宇宙线电子的能量密度在整个星系团中相对恒定，要么磁场随半径的衰减比先前认为的要慢得多。
引用
@article{arxiv.1208.3611,
title = {Planck intermediate results. X. Physics of the hot gas in the Coma cluster},
author = {Planck Collaboration and P. A. R. Ade and N. Aghanim and M. Arnaud and M. Ashdown and F. Atrio-Barandela and J. Aumont and C. Baccigalupi and A. Balbi and A. J. Banday and R. B. Barreiro and J. G. Bartlett and E. Battaner and K. Benabed and A. Benoît and J. -P. Bernard and M. Bersanelli and I. Bikmaev and H. Böhringer and A. Bonaldi and J. R. Bond and J. Borrill and F. R. Bouchet and H. Bourdin and M. L. Brown and S. D. Brown and R. Burenin and C. Burigana and P. Cabella and J. -F. Cardoso and P. Carvalho and A. Catalano and L. Cayón and L. -Y Chiang and G. Chon and P. R. Christensen and E. Churazov and D. L. Clements and S. Colafrancesco and L. P. L. Colombo and A. Coulais and B. P. Crill and F. Cuttaia and A. Da Silva and H. Dahle and L. Danese and R. J. Davis and P. de Bernardis and G. de Gasperis and A. de Rosa and G. de Zotti and J. Delabrouille and J. Démoclès and F. -X. Désert and C. Dickinson and J. M. Diego and K. Dolag and H. Dole and S. Donzelli and O. Doré and U. Dörl and M. Douspis and X. Dupac and T. A. Enßlin and H. K. Eriksen and F. Finelli and I. Flores-Cacho and O. Forni and M. Frailis and E. Franceschi and M. Frommert and S. Galeotta and K. Ganga and R. T. Génova-Santos and M. Giard and M. Gilfanov and J. González-Nuevo and K. M. Górski and A. Gregorio and A. Gruppuso and F. K. Hansen and D. Harrison and S. Henrot-Versillé and C. Hernández-Monteagudo and S. R. Hildebrandt and E. Hivon and M. Hobson and W. A. Holmes and A. Hornstrup and W. Hovest and K. M. Huffenberger and G. Hurier and T. R. Jaffe and T. Jagemann and W. C. Jones and M. Juvela and E. Keihänen and I. Khamitov and R. Kneissl and J. Knoche and L. Knox and M. Kunz and H. Kurki-Suonio and G. Lagache and A. Lähteenmäki and J. -M. Lamarre and A. Lasenby and C. R. Lawrence and M. Le Jeune and R. Leonardi and P. B. Lilje and M. Linden-Vørnle and M. López-Caniego and P. M. Lubin and J. F. Macías-Pérez and B. Maffei and D. Maino and N. Mandolesi and M. Maris and F. Marleau and E. Martínez-González and S. Masi and M. Massardi and S. Matarrese and F. Matthai and P. Mazzotta and S. Mei and A. Melchiorri and J. -B. Melin and L. Mendes and A. Mennella and S. Mitra and M. -A. Miville-Deschênes and A. Moneti and L. Montier and G. Morgante and D. Munshi and J. A. Murphy and P. Naselsky and P. Natoli and H. U. Nørgaard-Nielsen and F. Noviello and D. Novikov and I. Novikov and S. Osborne and F. Pajot and D. Paoletti and O. Perdereau and F. Perrotta and F. Piacentini and M. Piat and E. Pierpaoli and R. Piffaretti and S. Plaszczynski and E. Pointecouteau and G. Polenta and N. Ponthieu and L. Popa and T. Poutanen and G. W. Pratt and S. Prunet and J. -L. Puget and J. P. Rachen and R. Rebolo and M. Reinecke and M. Remazeilles and C. Renault and S. Ricciardi and T. Riller and I. Ristorcelli and G. Rocha and M. Roman and C. Rosset and M. Rossetti and J. A. Rubiño-Martín and L. Rudnick and B. Rusholme and M. Sandri and G. Savini and B. M. Schaefer and D. Scott and G. F. Smoot and F. Stivoli and R. Sudiwala and R. Sunyaev and D. Sutton and A. -S. Suur-Uski and J. -F. Sygnet and J. A. Tauber and L. Terenzi and L. Toffolatti and M. Tomasi and M. Tristram and J. Tuovinen and M. Türler and G. Umana and L. Valenziano and B. Van Tent and J. Varis and P. Vielva and F. Villa and N. Vittorio and L. A. Wade and B. D. Wandelt and N. Welikala and S. D. M. White and D. Yvon and A. Zacchei and S. Zaroubi and A. Zonca},
journal= {arXiv preprint arXiv:1208.3611},
year = {2015}
}
备注
20 pages, 18 figure, accepted by A&A, replaced to match published version