Development of Iodine Cells for the Subaru HDS and the Okayama HIDES : II. New Software for Precise Radial Velocity Measurements
Development of Iodine Cells for the Subaru HDS and the Okayama HIDES : II. New Software for Precise Radial Velocity Measurements
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DOI：
10.1093/pasj/54.6.873
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发表时间：
2002-12
影响因子：
2.3
通讯作者：
B. Sato;E. Kambe;Y. Takeda;H. Izumiura;H. Ando
中科院分区：
文献类型：
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作者：
B. Sato;E. Kambe;Y. Takeda;H. Izumiura;H. Ando
我们研制了一套计算机程序，用于在Subaru望远镜的高色散摄谱仪（HDS）和冈山188厘米反射镜的高色散中阶梯摄谱仪（HIDES）上安装碘（I_2）盒，精确测量恒星径向速度变化。我们的建模技术I2数据是类似的巴特勒等人所描述的。（1996，AAA 65.036.447）和Valenti et al.（1995年，AAA 64.036.209）关于通过I2细胞拍摄的恒星光谱（星星+ I2光谱）被建模为高分辨率恒星和I2模板光谱与摄谱仪的建模仪器轮廓（IP）卷积的产物。为了生成模板恒星光谱，我们设计了一种从观测到的星星+ I2光谱中提取本征恒星光谱的新方法。这使我们能够获得一个完善的模板恒星光谱，即使在IP和波长尺度容易随时间和观测条件而变化的情况下，现有的方法，重建IP从B星+ I2光谱（巴特勒等1996年; Endl等2000年，A&A，362，585）失败。本文报道了我们利用HDS和HIDES近一年来收集的数据对天鹅座16 B、τ Cet和天鹅座16 A三颗太阳型星进行多普勒测量的结果。这些结果表明，我们已经实现了约5- 6 ms-1的精度在一年的时间跨度与我们目前的分析包与两个光谱仪。
We have developed a computer code for precise measurements of stellar radial velocity variations with iodine (I2) cells attached to the High Dispersion Spectrograph (HDS) on Subaru Telescope and the HIgh Dispersion Echelle Spectrograph (HIDES) on Okayama 188cm reflector. Our modeling technique for I2 data is similar to those described by Butler et al. (1996, AAA 65.036.447) and Valenti et al. (1995, AAA 64.036.209) concerning the point that the stellar spectrum taken through the I2 cell (star + I2 spectrum) is modeled as the product of high-resolution stellar and I2 template spectra convolved with the modeled instrumental profile (IP) of the spectrograph. In order to generate a template stellar spectrum, we have devised a new method to extract an intrinsic stellar spectrum from observed star + I2 spectra. This enables us to obtain a well-established template stellar spectrum even in cases when the IP and the wavelength scale are apt to vary with time and the observational conditions, and the existing method which reconstructs the IP from a B-star + I2 spectrum (Butler et al. 1996; Endl et al. 2000, A&A, 362, 585) fails. We here report on the results of our Doppler measurements of three solar-type stars, 16 Cyg B, τ Cet, and υ And, based on data collected with HDS and HIDES for about one year. These results show that we have achieved a precision of about 5–6ms −1 over a time span of one year with our current analysis package with both spectrographs.