Detecting Extra-Solar Planets: Crossing the Jupiter Threshold

9520443马西，我们的太阳系仍然是已知的唯一围绕一颗正常恒星运行的行星系统。目前的观测工作未能发现质量是木星的三倍的太阳系外行星，这些行星围绕着大约30颗太阳型恒星运行。将通过观测HMST恒星的反射加速度(由多普勒效应测量)来搜索太阳系外行星。由于我们的太阳主要由于木星而发生13米/秒的速度幅度变化(从太阳系外观察到)，计划实现2米/秒的多普勒测量精度，以确保探测到围绕其他恒星运行的巨行星。这种前所未有的多普勒测量精度源于频谱设计和频谱分析方面的新发展。此外，一台新的施密特相机经过特殊设计，可以在快速梯形光谱仪的全格式上产生锐利的对称点扩展函数(PSF)。将使用一个2048x2048ccd探测器来收集1000埃波长内分布在3万个ccd像素上的所有恒星多普勒信息。对光谱中的多普勒频移的分析将包括一种全新的同时求解所有光谱仪参数(波长尺度和PSF)和多普勒频移的方法。对多普勒测量的详细误差预算产生2米/秒的底线精度。这种精确度使得对类木星行星的探测可以在5西格马的水平上进行，而类土星行星的探测将微乎其微。对类太阳恒星光谱的实际测试观测使人们能够达到3.5米/秒的精度。这种精确度将通过下一代多普勒分析技术得到提高。然而，通过对五组曝光进行平均，平均误差不到2米/秒。它计划监测15颗G型和K型恒星，并对多普勒波长漂移进行测量，精度为2米/秒。将以5米/秒的精度观测85颗其他恒星，测量多普勒波长漂移(取决于单个恒星的亮度)。这些新技术将使在3年内观测恒星和测量速度变化成为可能，这些变化表明存在巨大的行星。

9520443 Marcy Our Solar System remains the lone planetary system that is known to be around a normal star. Current observational efforts have failed to discover extrasolar planets at a threshold of the mass three times that of Jupiter orbiting approximately 30 solar-type stars. A search for extrasolar planets, by observing the reflex acceleration of the hmst stars, measured by the Doppler effect, will be carried out. As our Sun executes a velocity amplitude change of 13 m/sec (as observed from outside the solar system) due primarily to Jupiter, it is planned to achieve a Doppler measurement precision of 2 m/sec to ensure detection of giant planets orbiting around other stars. This unprecedented Doppler measurement precision stems from novel developments in spec- trometer design and spectral analysis. In addition, a new Schmidt camera has been specially engineered to produce a sharp, symmetric Point Spread Function (PSF) over the full format of a fast echelle spectrometer. A 2048x2048 CCD detector will be used to gather all stellar Doppler information, within 1000 Angstroms wavelength, spread over 30,000 CCD pixels. The analysis of the Doppler shifts in the spectra will consist of an entirely novel simultaneous solution of all spectrometer parameters (wavelength scale and PSF) and Doppler shift. A detailed error budget for the Doppler measurements yields a bottom line accuracy of 2 m/sec. This precision renders the detection of Jupiter-like planets detectable at the 5 sigma level, and Saturn-like planets will be marginally detectable. Actual test observations of the spectra of Solar-like stars enable one to achieve a precision of 3.5 m/sec. This accuracy will be improved with the next-generation Doppler analysis techniques. Already, however, by averaging sets of five exposures, the error in the mean is less than 2 m/sec. It is planned to monitor 15 G-type and K- type stars and make measurements of the Doppler wavelength shifts to a precision of 2 m/sec. Eighty five other stars will be observed with an accuracy of 5 m/sec in the measurement of the Doppler wavelength shifts (depending on the brightness of the individual stars). These new techniques will make it possible to observe stars and measure velocity changes, indicative of giant planets, within 3 years.