CHARACTERIZING COSMIC-RAY PROPAGATION IN MASSIVE STAR-FORMING REGIONS: THE CASE OF 30 DORADUS AND THE LARGE MAGELLANIC CLOUD
CHARACTERIZING COSMIC-RAY PROPAGATION IN MASSIVE STAR-FORMING REGIONS: THE CASE OF 30 DORADUS AND THE LARGE MAGELLANIC CLOUD
复制标题
描述大质量恒星形成区域中宇宙射线传播的特征：剑鱼座 30 和大麦哲伦星云的案例
DOI：
10.1088/0004-637x/750/2/126
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
A. Strong
中科院分区：
文献类型：
--
作者：
Eric J. Murphy;T. Porter;I. Moskalenko;G. Helou;A. Strong
利用红外、射电和γ射线观测数据，采用基于星系内射电-远红外关联的唯象模型，研究了大麦哲伦云（LMC）剑鱼座30（30 Dor）恒星形成区宇宙射线（CR）电子和原子核的传播特性.利用相关分析，结合射电和红外数据，我们得到了30 Dor内1.3GeV的CR电子的平均传播长度为100-140 pc。假设观测到的朝向30 Dor的γ射线发射与恒星形成区有关，并将相同的方法应用于红外和γ射线数据，我们估计CR核的20 GeV传播长度为200-320 pc。这大约是103 GeV CR电子的两倍，对应的空间扩散系数是1044倍，根据相关分析中使用的涂抹核，缩放为（R/GV）δ，δ为0.7-0.8。这一结果与将相关分析扩展到包括由3-10 GeV γ射线数据追踪的1070 GeV CR核所得到的结果一致（δ = 0.66 ± 0.23）。利用30 Dor中恒星群体的平均年龄和我们相关分析的结果，我们估计扩散系数DR =（0.9-1.0）× 1027（R/GV）0.7 cm 2 s−1。我们比较的CR电子传播长度和表面亮度的30 Dor和大麦哲伦星系作为一个整体与整个盘星系的值。我们发现，减少平均CR传播距离的趋势，增加磁盘平均星星形成活动的大麦哲伦星云，并延伸到单个恒星形成区，至少在30 Dor的情况下。
Using infrared, radio, and γ-ray data, we investigate the propagation characteristics of cosmic-ray (CR) electrons and nuclei in the 30 Doradus (30 Dor) star-forming region in the Large Magellanic Cloud (LMC) using a phenomenological model based on the radio–far-infrared correlation within galaxies. Employing a correlation analysis, we derive an average propagation length of ∼100–140 pc for ∼3 GeV CR electrons resident in 30 Dor from consideration of the radio and infrared data. Assuming that the observed γ-ray emission toward 30 Dor is associated with the star-forming region, and applying the same methodology to the infrared and γ-ray data, we estimate a ∼20 GeV propagation length of 200–320 pc for the CR nuclei. This is approximately twice as large as for ∼3 GeV CR electrons, corresponding to a spatial diffusion coefficient that is ∼4 times higher, scaling as (R/GV)δ with δ ≈ 0.7–0.8 depending on the smearing kernel used in the correlation analysis. This value is in agreement with the results found by extending the correlation analysis to include ∼70 GeV CR nuclei traced by the 3–10 GeV γ-ray data (δ ≈ 0.66 ± 0.23). Using the mean age of the stellar populations in 30 Dor and the results from our correlation analysis, we estimate a diffusion coefficient DR ≈ (0.9–1.0) × 1027(R/GV)0.7 cm2 s−1. We compare the values of the CR electron propagation length and surface brightness for 30 Dor and the LMC as a whole with those of entire disk galaxies. We find that the trend of decreasing average CR propagation distance with increasing disk-averaged star formation activity holds for the LMC, and extends down to single star-forming regions, at least for the case of 30 Dor.
DOI：
10.1088/0004-637x/720/1/226
发表时间：
2010-09
期刊：
The Astrophysical Journal
影响因子：
--
作者：
P. Papadopoulos
通讯作者：
P. Papadopoulos
DOI：
10.1088/0004-6256/136/3/919
发表时间：
2005-06
期刊：
The Astronomical Journal
影响因子：
--
作者：
M. Meixner;K. Gordon;R. Indebetouw;J. Hora;B. Whitney;R. Blum;W. Reach;J. Bernard;M. Meade;B. Babler;C. Engelbracht;B. For;K. Misselt;U. Vijh;C. Leitherer;M. Cohen;E. Churchwell;F. Boulanger;J. Frogel;Y. Fukui;J. Gallagher;V. Gorjian;J. Harris;D. Kelly;A. Kawamura;Soyoung Kim;W. Latter;S. Madden;Ciska Markwick-Kemper;A. Mizuno;N. Mizuno;J. Mould;A. Nota;M. Oey;K. Olsen;T. Onishi;R. Paladini;N. Panagia;P. Pérez-González;H. Shibai;Sato Shuji;Linda J. Smith;L. Staveley-Smith;A. Tielens;T. Ueta;S. V. Dyk;K. Volk;M. Werner;D. Zaritsky
通讯作者：
M. Meixner;K. Gordon;R. Indebetouw;J. Hora;B. Whitney;R. Blum;W. Reach;J. Bernard;M. Meade;B. Babler;C. Engelbracht;B. For;K. Misselt;U. Vijh;C. Leitherer;M. Cohen;E. Churchwell;F. Boulanger;J. Frogel;Y. Fukui;J. Gallagher;V. Gorjian;J. Harris;D. Kelly;A. Kawamura;Soyoung Kim;W. Latter;S. Madden;Ciska Markwick-Kemper;A. Mizuno;N. Mizuno;J. Mould;A. Nota;M. Oey;K. Olsen;T. Onishi;R. Paladini;N. Panagia;P. Pérez-González;H. Shibai;Sato Shuji;Linda J. Smith;L. Staveley-Smith;A. Tielens;T. Ueta;S. V. Dyk;K. Volk;M. Werner;D. Zaritsky
影响因子：
9.6
作者：
Romero-Corral, Abel;Caples, Sean M.;Somers, Virend K.
通讯作者：
Somers, Virend K.