Grain Properties of Comet C/1995 O1 (Hale-Bopp)
Grain Properties of Comet C/1995 O1 (Hale-Bopp)
复制标题
彗星 C/1995 O1 (Hale-Bopp) 的颗粒特性
DOI：
10.1086/343091
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
C. Lisse
中科院分区：
文献类型：
--
作者：
D. Harker;D. Wooden;C. Woodward;C. Lisse
我们对 C/1995 O1 (Hale-Bopp) 彗星的 7.6-13.2 μm 红外 (IR) 分光光度法 (R ≃ 250) 进行分析，并结合同步观测，将光谱能量分布的波长覆盖范围从近红外波长扩展到远红外波长。观测数据包括近日点前（世界标准时间 1996 年 10 月和 1997 年 2 月）、近日点附近（世界标准时间 1997 年 4 月）和近日点后（世界标准时间 1997 年 6 月）。通过对海尔-波普彗发中的小无定形碳颗粒以及结晶和无定形硅酸盐颗粒的热发射进行建模，我们发现当彗星接近近日点时，颗粒尺寸分布（汉纳修正幂律）变陡（从近日点前的 N = 3.4 到近日点附近和后的 N = 3.7），同时分形孔隙率增大（大于 1 μm）。谷物。每个时期的晶粒尺寸分布峰值保持恒定（ap = 0.2 μm）。我们将近日点附近 9.3 μm 峰值的出现归因于高喷流活动时期释放的结晶斜方辉石颗粒。结晶硅酸盐（橄榄石和斜方辉石）约占每个历元海尔-波普彗发中亚微米级（≤1μm）尘埃颗粒的 30%（按质量计）。
We present the analysis of 7.6-13.2 μm infrared (IR) spectrophotometry (R ≃ 250) of comet C/1995 O1 (Hale-Bopp), in conjunction with concurrent observations that extend the wavelength coverage of the spectral energy distribution from near- to far-infrared wavelengths. The observations include temporal epochs preperihelion (1996 October and 1997 February UT), near perihelion (1997 April UT), and postperihelion (1997 June UT). Through the modeling of the thermal emission from small, amorphous carbon grains and crystalline and amorphous silicate grains in Hale-Bopp's coma, we find that as the comet approached perihelion, the grain size distribution (the Hanner modified power law) steepened (from N = 3.4 preperihelion to N = 3.7 near and postperihelion), along with an increase in the fractal porosity of larger (greater than 1 μm) grains. The peak of the grain size distribution remained constant (ap = 0.2 μm) at each epoch. We attribute the emergence of the 9.3 μm peak near perihelion to crystalline orthopyroxene grains released during epochs of high jet activity. Crystalline silicates (olivine and orthopyroxene) make up about 30% (by mass) of the submicron-sized (≤1 μm) dust grains in Hale-Bopp's coma during each epoch.
泰坦的有机气溶胶。
DOI：
10.1016/0273-1177(84)90545-3
发表时间：
1984
期刊：
Advances in space research : the official journal of the Committee on Space Research (COSPAR)
影响因子：
--
作者：
Khare,BN;Sagan,C;Thompson,WR;Arakawa,ET;Suits,F;Callcott,TA;Williams,MW;Shrader,S;Ogino,H;Willingham,TO;Nagy,B
通讯作者：
Nagy,B
影响因子：
3.2
作者：
V. Mannings;A. Boss;S. Russell
通讯作者：
V. Mannings;A. Boss;S. Russell