We present the results of far-ultraviolet observations of comet C/2001 Q4 (NEAT) that were made with the Far-Ultraviolet Imaging Spectrograph on board the Korean satellite STSAT-1. The observations were conducted in two campaigns during its perihelion approach between 2004 May 8 and 15. Based on the scanning mode observations in the wavelength band of 1400-1700 ?, we have constructed an image of the comet with an angular size of 5°×5°, which corresponds to the central coma region. Several important fluorescence emission lines were detected including S I multiplets at 1429 and 1479 ?, C I multiplets at 1561 and 1657 ?, and the CO A1Π-X1Σ+ Fourth Positive system; we have estimated the production rates of the corresponding species from the fluxes of these emission lines. The estimated production rate of CO was Q CO?= (2.65?± 0.63) × 1028?s–1, which is 6.2%-7.4% of the water production rate and is consistent with earlier predictions. The average carbon production rate was estimated to be QC ?= ~1.59 × 1028?s–1, which is ~60% of the CO production rate. However, the observed carbon profile was steeper than that predicted using the two-component Haser model in the inner coma region, while it was consistent with the model in the outer region. The average sulfur production rate was QS ?= (4.03±1.03) × 1027?s–1, which corresponds to ~1% of the water production rate.
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机译：我们介绍了利用韩国卫星STSAT-1上的远紫外成像光谱仪对C / 2001 Q4彗星（NEAT）进行的远紫外观测结果。在2004年5月8日至15日的近日点进近期间，在两次运动中进行了观测。基于在1400至1700λ波段的扫描模式观测，我们构造了角大小为5°×的彗星图像。 5°，对应于中央昏迷区域。检测到了几个重要的荧光发射线，包括1429和1479？处的S I多重峰，1561和1657？处的C I多重峰以及COA1Π-X1Σ+第四正系统。我们已经根据这些排放线的通量估算了相应物种的生产率。估计的CO产生率为Q CO2 =（2.65？±0.63）×1028？s-1，占水生产率的6.2％-7.4％，与先前的预测一致。平均碳生产率估计为QC？=〜1.59×1028？s-1，约为CO生产率的60％。但是，观察到的碳剖面在内部昏迷区域比使用两组分Haser模型预测的碳剖面要陡，而与外部区域的模型一致。平均硫产生率为QS？=（4.03±1.03）×1027？s-1，相当于水产生率的〜1％。
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