ALMA CO Observations of Gamma-Ray Supernova Remnant N132D in the Large Magellanic Cloud: Possible Evidence for Shocked Molecular Clouds Illuminated by Cosmic-Ray Protons
H. Sano, P. P. Plucinsky, A. Bamba, P. Sharda, M. D. Filipovic, C. J. Law, R. Z. E. Alsaberi, Y. Yamane, K. Tokuda, F. Acero, M. Sasaki, J. Vink, T. Inoue, S. I… 展开作者
H. Sano, P. P. Plucinsky, A. Bamba, P. Sharda, M. D. Filipovic, C. J. Law, R. Z. E. Alsaberi, Y. Yamane, K. Tokuda, F. Acero, M. Sasaki, J. Vink, T. Inoue, S. Inutsuka, J. Shimoda, K. Tsuge, K. Fujii, F. Voisin, N. Maxted, G. Rowell, T. Onishi, A. Kawamura, N. Mizuno, H. Yamamoto, K. Tachihara, Y. Fukui
N132D is the brightest gamma-ray supernova remnant (SNR) in the Large Magellanic Cloud (LMC). We carried out $^{12}$CO($J$ = 1-0, 3-2) observations toward the SNR using the Atacama Large Millimeter/submillimeter Array (ALMA) and Atacama Submillimeter Telescope Experiment. We find diffuse CO emission not only at the southern edge of the SNR as previously known, but also inside the X-ray shell. We spatially resolved nine molecular clouds using ALMA with an angular resolution of $5''$, corresponding to a spatial resolution of $\sim$1 pc at the distance of the LMC. Typical cloud sizes and masses are $\sim$2.0 pc and $\sim$100 $M_\odot$, respectively. High-intensity ratios of CO $J$ = 3-2 / 1-0 $> 1.5$ are seen toward the molecular clouds, indicating that shock-heating has occurred. Spatially resolved X-ray spectroscopy reveals that thermal X-rays in the center of N132D are produced not only behind a molecular cloud, but also in front of it. Considering the absence of a thermal component associated with the forward shock towards one molecular cloud located along the line of sight to the center of the remnant, this suggests that this particular cloud is engulfed by shock waves and is positioned on the near side of remnant. If the hadronic process is the dominant contributor to the gamma-ray emission, the shock-engulfed clouds play a role as targets for cosmic-rays. We estimate the total energy of cosmic-ray protons accelerated in N132D to be $\sim$0.5-$3.8 \times 10^{49}$ erg as a conservative lower limit, which is similar to that observed in Galactic gamma-ray SNRs.
The X-ray emission from a supernova remnant is a powerful diagnostic of the state of its shocked plasma. The temperature and the emission measure are related to the energy of the explosion, the age of the remnant, and the density of the surrounding medium. Here we present the results of a study of the remnant population of the Small Magellanic Cloud. Progress in X-ray observations of remnants has resulted in a sample of 20 remnants in the Small Magellanic Clound with measured temperatures and emission measures. We apply spherically symmetric supernova remnant evolution models to this set of re…
A Detailed Archival CHANDRA Study of the Young Core-Collapse Supernova Remnant 1E 0102.2-7219 in the Small Magellanic Cloud
我们提出了一个档案钱德拉研究的富氧超新星遗迹（SNR）1 E 0102.2-7219在小麦哲伦星云。基于深$\sim$ 265 ks档案钱德拉数据，我们进行了详细的空间分辨光谱分析1 E 0102.2-7219。我们的目标是以前所未有的细节揭示这个遗迹的空间和化学结构。根据我们对沿1 E 0102.2-7219的9个不同方位角方向提取的区域光谱的分析，O、Ne和Mg丰度的径向分布表明，在距离SNR X射线发射几何中心$\sim$ 5-5.5 pc处存在接触不连续性。我们发现，富含金属的喷出物气体进一步向外延伸在西部和西南部比其他方向的SNR。喷出物的平均O/Ne、O/Mg和Ne/Mg丰度比与$\sim 40 M_\odot$祖先爆炸的核合成产物似乎一致。我们估计1 E 0102.2-7219的Sedov年龄上限为$\sim 3500$年，爆炸能量上限为$\sim 1.8\times10^{51}$尔格。我们讨论的影响，我们的结果的几何结构的残余，其拱星介质和祖星的性质。我们的研究结果不适合一个简单的图片的反向冲击发射从一个球壳状喷出物气体均匀分布的金属丰度和幂律密度沿半径的SNR。
This study explores the link between the [OIII]88mu emission, a well-known tracer of HII regions, and 24mu continuum, often used to trace warm dust in the ionized phases of galaxies. We investigate the local conditions driving the relation between those tracers in the Magellanic Clouds, comparing observations with Cloudy models consisting of an HII region plus a photodissociation region (PDR) component, varying the stellar age, the initial density (at the illuminated edge of the cloud), and the ionization parameter. We introduce a new parameter, cPDR, to quantify the proportion of emission ari…
We present HST/WFC3 multiband imagery of N103B, the remnant of a Type Ia supernova in the Large Magellanic Cloud, as well as HST/COS ultraviolet spectroscopy of the brightest radiatively shocked region. The images show a wide range of morphology and relative emission-line intensities, from smooth Balmer-line dominated collisionless shocks due to the primary blast wave, to clumpy radiative shock filaments due to secondary shocks in density enhancements. The COS data show strong FUV line emission despite a moderately high extinction along this line of sight. We use the COS data with previous opt…
Evolutionary Models for 15 Galactic Supernova Remnants with New Distances
最近利用21 cm HI线和$^{13}$ CO线对银河系内部的观测研究，获得了30个银河系超新星遗迹（SNRs）的新距离。其中15个残骸已经观测到X射线光谱，并测量了冲击气体的温度和排放量。在这里，我们应用球对称SNR演化模型，这15个遗迹，以获得估计的年龄，爆炸能量，星周介质密度和配置文件（均匀或风型）。从年龄的分布，我们得到了超新星的诞生率和估计的不完整性。能量和密度可以很好地拟合对数正态分布。爆炸能量的分布与大麦云云（LMC）中的超新星爆炸非常相似，表明LMC中的超新星爆炸与银河系中的超新星爆炸非常相似。银河系信噪比的密度分布比大麦哲伦星系信噪比的平均密度高出$\sim$ 2.5倍。
