Characterization and Commissioning of the iLocater Spectrograph

iLocater 光谱仪的表征和调试

• 批准号: 2108603
• 负责人: Jonathan Crass
• 金额: $ 114.34万
• 依托单位: University of Notre Dame
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2108603&HistoricalAwards=false
• 关键词: Characterization; Commissioning; iLocater; Spectrograph

This project will complete the construction of a new instrument named iLocater that will search for exoplanets using a large telescope in Arizona. iLocater is an instrument called a spectrograph that spreads out the incoming light from stars and searches for the tiny color changes caused by planets moving in orbit around their star. The instrument compensates for the distorting effect of Earth’s turbulent atmosphere and can use small optical fibers to bring light from the telescope to the spectrograph. This feature allows scientists to see both the color changes caused by planets and the effects of the changing surface of stars which enable discovery and study of even smaller exoplanets that can currently be detected. iLocater is designed to be extremely stable to allow the detection of the incredibly small color change caused by planets to be measured. iLocater will undertake studies of exoplanetary systems to characterize their properties and assess their potential to support life. The project will supply training for graduate students in developing instrumentation and also summer research opportunities for undergraduate studentsThe performance of modern Doppler instruments is dominated by the effects of stellar variability, an effect that imprints the signature of surface inhomogeneities and stochastic motions onto stellar spectra. Such astrophysical jitter imposes a noise floor by creating temporally changing asymmetries in the absorption lines of stellar spectra. This project will complete building a Doppler precision radial velocity instrument that uses adaptive optics (AO) and single-mode fibers (SMFs) on a large telescope to achieve high spectral resolution (R=132,000-273,000). The instrument, named iLocater, will be installed on the Large Binocular Telescope (LBT) in Arizona and operates at the diffraction limit at near-infrared (NIR) wavelengths (YJ-bands). The NIR bandpass is well suited to AO performance, is expected to be less susceptible to stellar variability, and provides access to the peak radiation of late-type stars where the Doppler amplitudes of planets are substantially larger than those orbiting G-type stars. The combination of high spectral resolution and high spatial resolution (41 mas) will facilitate novel research directions, such as studying planets orbiting close separation binaries. On completion iLocater will be available to many US astronomers who are within the LBT community for 30 nights/year and there will be public access to the iLocater data products.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该项目将完成一个名为iLocater的新仪器的建造，该仪器将使用亚利桑那州的大型望远镜搜索系外行星。iLocater是一种被称为光谱仪的仪器，它将来自恒星的入射光展开，并搜索行星在围绕其星星的轨道上运动时引起的微小颜色变化。该仪器补偿了地球湍流大气的扭曲效应，并可以使用小光纤将光线从望远镜带到光谱仪。这一特征使科学家能够看到行星引起的颜色变化和恒星表面变化的影响，从而能够发现和研究目前可以探测到的更小的系外行星。iLocater的设计非常稳定，可以检测由行星引起的令人难以置信的微小颜色变化。iLocater将对系外行星系统进行研究，以确定其特性并评估其支持生命的潜力。 该项目将为研究生提供开发仪器的培训，并为本科生提供夏季研究机会。现代多普勒仪器的性能主要受恒星变化的影响，这种影响将表面不均匀性和随机运动的特征印在恒星光谱上。这种天体物理抖动通过在恒星光谱的吸收线中产生随时间变化的不对称性来施加本底噪声。 该项目将完成在大型望远镜上使用自适应光学（AO）和单模光纤（SMF）的多普勒精密径向速度仪器的建造，以实现高光谱分辨率（R= 132，000 - 273，000）。该仪器名为iLocater，将安装在亚利桑那州的大型双目望远镜（LBT）上，并在近红外（NIR）波长（YJ波段）的衍射极限下工作。近红外带通非常适合AO性能，预计将不太容易受到恒星的变化，并提供访问晚型恒星的峰值辐射的行星的多普勒振幅大大大于那些轨道G型恒星。高光谱分辨率和高空间分辨率（41 mas）的结合将促进新的研究方向，例如研究围绕近距离双星运行的行星。 完成后，iLocater将提供给许多美国天文学家谁是在LBT社区30晚/年，将有公众访问iLocater数据产品。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

项目成果

The final design of the iLocater spectrograph: an optimized architecture for diffraction-limited EPRV instruments

iLocater 摄谱仪的最终设计：衍射极限 EPRV 仪器的优化架构

• DOI: 10.1117/12.2630228
• 发表时间: 2022
• 期刊: Volume 12184
• 作者: Crass, Jonathan;Aikens, David M.;Mason, Joaquin;King, David L.;Crepp, Justin R.;Bechter, Andrew;Bechter, Eric B.;Farsad, Mahsa;Schwab, Christian;VanSickle, Michael
• 通讯作者: VanSickle, Michael

The iLocater cryostat and thermal control system: enabling extremely precise radial velocity measurements for diffraction-limited spectrographs

iLocater 低温恒温器和热控制系统：为衍射极限光谱仪提供极其精确的径向速度测量

• DOI: 10.1117/12.2630199
• 发表时间: 2022
• 期刊: Volume 12184
• 作者: Crass, Jonathan;Sadagopan, Nandini;Misch, Matthew;Rizika, Alexa;Sands, Brian;Engstrom, Matthew;Crepp, Justin R.;Smous, James;Chilcote, Jeffrey;Fantano, Louis G.
• 通讯作者: Fantano, Louis G.