The Roman Coronagraph is expected to perform its high-order wavefront sensing and control (HOWFSC) with a ground-in-the-loop scheme due to the computational complexity of the Electric-Field-Conjugation (EFC) algorithm. This scheme provides the flexibility to alter the HOWFSC algorithm for given science objectives. A new alternative implicit-EFC algorithm is of particular interest as it requires no optical model to create a dark-hole, making the final contrast independent of the model accuracy. The intended HOWFSC scheme involves running EFC while observing a bright star such as $ζ$ Puppis to create the initial dark-hole, then slew to the science target while maintaining the contrast with low-order WFSC over the given observation.
Given a similar scheme, the efficacy of iEFC is simulated for two coronagraph modes, namely the Hybrid Lyot Coronagraph (HLC) and the wide-field-of-view Shaped-Pupil-Coronagraph (SPC-WFOV). End-to-end physical optics models for each mode serve as the tool for the simulations. Initial monochromatic simulations are presented and compared with monochromatic EFC results obtained with the FALCO software. Various sets of calibration modes are tested to understand the optimal modes to use when generating an iEFC response matrix. Further iEFC simulations are performed using broadband images with the assumption that $ζ$ Puppis is the stellar object being observed. Shot noise, read noise, and dark current are included in the broadband simulations to determine if iEFC could be a suitable alternative to EFC for the Roman Coronagraph.
The Roman Coronagraph Community Participation Program: Using the Zernike wavefront sensor for a full characterisation of the Roman Space Telescope and the Coronagraph Instrument
Aix Marseille Univ, CNRS, CNES, LAM（艾克斯马赛大学）；Space Telescope Science Institute（太空望远镜科学研究所）；Laboratoire Lagrange, Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS（拉格朗日实验室，蔚蓝海岸大学，蔚蓝海岸天文台）；Jet Propulsion Laboratory, California Institute of Technology（喷气推进实验室，加州理工学院）
NASA's next flagship mission, the Nancy Grace Roman Space Telescope, is a 2.4-meter observatory set to launch no later than May 2027. Roman features two instruments: the Wide Field Imager and the Coronagraph Instrument. Roman's Coronagraph is a Technology Demonstration that will push the current capabilities of direct imaging to smaller contrast ratios ($\sim$10$^{-9}$) and inner-working angles (3~$λ$/D). In order to achieve this high precision, Roman Coronagraph data must be calibrated to remove as many potential sources of error as possible. Here we present a detailed overview of the Nancy G…
The Nancy Grace Roman Space Telescope's (Roman) Coronagraph Instrument is a technology demonstration equipped to achieve flux contrast levels of up to 10$^{-9}$. This precision depends upon the quality of observations and their resultant on-sky corrections via an absolute flux calibration (AFC). Our plan utilizes 10 dim and 4 bright standard photometric calibrator stars from Hubble Space Telescope's (HST) CALSPEC catalog to yield a final AFC error of 1.94\% and total observation time of $\sim$22 minutes. Percent error accounts for systematic uncertainties (filters, upstream optics, quantum eff…
The Nancy Grace Roman Space Telescope Coronagraph Instrument will be the first large scale coronagraphmission with active wavefront control to be operated in space and will demonstrate technologies essential tofuture missions to image Earth-like planets. Consisting of multiple coronagraph modes, the coronagraph isexpected to characterize and image exoplanets at 1E-8 or better contrast levels. An object-oriented physicaloptics modeling tool called POPPY provides flexible and efficient simulations of high-contrast point spreadfunctions (PSFs). As such, three coronagraph modes have been modeled i…
The Nancy Grace Roman Space Telescope Coronagraph Instrument is a high-contrast imager, polarimeter, and spectrometer that will enable the study of exoplanets and circumstellar disks at visible wavelengths ($\sim$550--850~nm) at contrasts 2--3 orders of magnitude better than can currently be achieved by ground or space-based direct imaging facilities. To capitalize on this sensitivity, precise flux calibration will be required. The Roman Coronagraph, like other space-based missions, will use on-orbit flatfields to measure and correct for phenomena that impact the measured total effective throu…
This document summarizes how far the Nancy Grace Roman Space Telescope Coronagraph Instrument (Roman CGI) will go toward demonstrating high-contrast imaging and spectroscopic requirements for potential future exoplanet direct imaging missions, illustrated by the HabEx and LUVOIR concepts. The assessment is made for two levels of assumed CGI performance: (i) current best estimate (CBE) as of August 2020, based on laboratory results and realistic end-to-end simulations with JPL-standard Model Uncertainty Factors (MUFs); (ii) CGI design specifications inherited from Phase B requirements. We find …
The Roman Coronagraph Community Participation Program: target database and tools
Sibley School of Mechanical and Aerospace Engineering, Cornell University（康奈尔大学机械与航空航天工程学院）；Carl Sagan Institute, Cornell University（康奈尔大学卡尔·萨根研究所）；Department of Astronomy, Cornell University（康奈尔大学天文学系）；Steward Observatory and the Department of Astronomy, The University of Arizona（亚利桑那大学斯图尔德天文台及天文学系）；Tellus1 Scientific, LLC（Tellus1科学有限责任公司）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）
Over the past two decades, thousands of confirmed exoplanets have been detected; the next major challenge is to characterize these other worlds and their stellar systems. Much information on the composition and formation of exoplanets and circumstellar debris disks can only be achieved via direct imaging. Direct imaging is challenging because of the small angular separations ($<1$ arcsec) and high star-to-planet flux ratios (${\sim}10^{9}$ for a Jupiter analog or ${\sim}10^{10}$ for an Earth analog in the visible). Atmospheric turbulence prohibits reaching such high flux ratios on the ground, …
The Coronagraph Instrument (CGI) on the Nancy Grace Roman Space Telescope will demonstrate the high-contrast technology necessary for visible-light exoplanet imaging and spectroscopy from space via direct imaging of Jupiter-size planets and debris disks. This in-space experience is a critical step toward future, larger missions targeted at direct imaging of Earth-like planets in the habitable zones of nearby stars. This paper presents an overview of the current instrument design and requirements, highlighting the critical hardware, algorithms, and operations being demonstrated. We also describ…
The Roman Coronagraph Community Participation Program: corgisim - a simulation suite for the Nancy Grace Roman Space Telescope Coronagraph Instrument
University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；Aix Marseille Université（艾克斯-马赛大学）；Northwestern University（西北大学）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；DM Telescopes LLC（DM望远镜有限责任公司）；University of Alabama at Huntsville（阿拉巴马大学亨茨维尔分校）；National Astronomical Observatory of Japan（日本国立天文台）；Space Telescope Science Institute（空间望远镜科学研究所）；California Institute of Technology（加州理工学院）
Enhanced wavefront sensing for the Roman Coronagraph Instrument: Gaussian probes and compact model validation
LIRA, Observatoire de Paris, Université PSL, Sorbonne Université, Université Paris Cité, CY Cergy Paris Université, CNRS（巴黎天文台，PSL大学，索邦大学，巴黎西岱大学，CY塞尔吉巴黎大学，法国国家科学研究中心）；Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange（蔚蓝海岸大学，蔚蓝海岸天文台，法国国家科学研究中心）；Jet Propulsion Laboratory, California Institute of Technology（喷气推进实验室，加州理工学院）；Aix Marseille Univ, CNRS, CNES, LAM（艾克斯马赛大学，法国国家科学研究中心，法国国家空间研究中心）；NASA Ames Research Center（美国国家航空航天局阿姆斯特朗飞行研究中心）；Department of Astronomy & Astrophysics, University of California, Santa Cruz（加利福尼亚大学圣克鲁兹分校天文学与天体物理学系）；Space Telescope Science Institute（太空望远镜科学研究所）
Simulation tools for realistic high-order wavefront correction with the Roman Coronagraph
Aix Marseille Université（艾克斯-马赛大学）；CNES（法国国家空间研究中心）；LAM（拉格朗日天体物理实验室）；Jet Propulsion Laboratory（喷气推进实验室）；California Institute of Technology（加州理工学院）；Université Côte d’Azur（蔚蓝海岸大学）；Observatoire de la Côte d’Azur（蔚蓝海岸天文台）；Laboratoire Lagrange（拉格朗日实验室）；NASA Ames Research Center（美国宇航局埃姆斯研究中心）；LIRA（拉格朗日力学与天体物理学实验室）；Observatoire de Paris（巴黎天文台）；Université PSL（巴黎文理研究大学）；Sorbonne Université（索邦大学）；Université Paris Cité（巴黎西岱大学）；CY Cergy Paris Université（塞吉-巴黎大学）；Space Telescope Science Institute（太空望远镜科学研究所）；Centre de donnees Astrophysiques de Marseille (CeSAM)（马赛天体物理数据中心）
The Roman Coronagraph Community Participation Program: data reduction pipeline astrometric calibration
Northwestern University（西北大学）；Center for Interdisciplinary Exploration and Research in Astrophysics（天体物理跨学科探索与研究中心）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）；University of California Santa Barbara（加州大学圣塔芭芭拉分校）；Space Telescope Science Institute（太空望远镜科学研究所）
The Roman coronagraph instrument will demonstrate high-contrast imaging technology, enabling the imaging of faint debris disks, the discovery of inner dust belts, and planets. Polarization studies of debris disks provide information on dust grains' size, shape, and distribution. The Roman coronagraph uses a polarization module comprising two Wollaston prism assemblies to produce four orthogonally polarized images ($I_{0}$, $I_{90}$, $I_{45}$, and $I_{135}$), each measuring 3.2 arcsecs in diameter and separated by 7.5 arcsecs in the sky. The expected RMS error in the linear polarization fractio…
The Nancy Grace Roman Space Telescope Coronagraph Community Participation Program
Cornell University（康奈尔大学）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）；The University of Arizona（亚利桑那大学）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；Northwestern University（西北大学）；Aix Marseille Univ, CNRS, CNES, LAM（艾克斯马赛大学）；Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université Paris Cité（巴黎天文台）；University of Edinburgh（爱丁堡大学）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；Arizona State University（亚利桑那州立大学）；SRON Netherlands Institute for Space Research（荷兰空间研究研究所）；Space Telescope Science Institute（太空望远镜科学研究所）；Caltech（加州理工学院）；Massachusetts Institute of Technology（麻省理工学院）；University of California, Riverside（加州大学河滨分校）；Princeton University（普林斯顿大学）；Astrobiology Center, NINS（日本天体生物学中心）；National Astronomical Observatory of Japan（日本国立天文台）
CoronaGraph Instrument Reference stars for Exoplanets (CorGI-REx) I. Preliminary Vetting and Implications for the Roman Coronagraph and Habitable Worlds Observatory
The Roman Coronagraph Community Participation Program: trials and triumphs of designing an observing program for a technology demonstration instrument
The University of Arizona（亚利桑那大学）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）；University of Edinburgh（爱丁堡大学）；Cornell University（康奈尔大学）；Space Telescope Science Institute（太空望远镜科学研究所）；Laboratoire d’Astrophysique de Marseille（马赛天体物理实验室）；California Institute of Technology（加州理工学院）；Max Planck Institut for Astronomy（马克斯·普朗克天文学研究所）；Astrobiology Center, NINS（日本国立自然科学研究所天体生物学中心）；National Astronomical Observatory of Japan, NINS（日本国立天文台）；Johns Hopkins University（约翰斯·霍普金斯大学）；University of California, Santa Barbara（加利福尼亚大学圣塔芭芭拉分校）；Observatoire de Paris, Université PSL, CNRS, Université Paris Cité, Sorbonne Université（巴黎天文台、巴黎文理研究大学、法国国家科学研究中心、巴黎西岱大学、索邦大学）；Université Côte d’Azur（蔚蓝海岸大学）
A Roman Coronagraph Spectroscopic Mode Demonstration
University of Texas-San Antonio（德克萨斯大学圣安东尼奥分校）；Subaru Telescope, National Astronomical Observatory of Japan（昴望远镜，日本国立天文台）；University of California-Santa Cruz（加州大学圣克鲁兹分校）；University of Michigan（密歇根大学）；NASA Goddard Spaceflight Center（美国宇航局戈达德太空飞行中心）；National Astronomical Observatory of Japan（日本国立天文台）
The Nancy Grace Roman Space Telescope Coronagraph Instrument (CGI) will be capable of characterizing exoplanets in reflected light and will demonstrate space technologies essential for future missions to take spectra of Earthlike exoplanets. As the mission and instrument move into the final stages of design, simulation tools spanning from depth of search calculators to detailed diffraction models have been created by a variety of teams. We summarize these efforts, with a particular focus on publicly available datasets and software tools. These include speckle and point-spread-function models, …
Exozodiacal dust, warm debris from comets and asteroids in and near the habitable zone of stellar systems, reveals the physical processes that shape planetary systems. Scattered light from this dust is also a source of background flux which must be overcome by future missions to image Earthlike planets. This study quantifies the sensitivity of the Nancy Grace Roman Space Telescope Coronagraph to light scattered by exozodi, the zodiacal dust around other stars. Using a sample of 149 nearby stars, previously selected for optimum detection of habitable exoplanets by space observatories, we find t…
Technology and Science Advancing Observations with Roman Coronagraph Informed by Ground-Based High-Contrast Imaging
University of Texas at San Antonio（德克萨斯大学圣安东尼奥分校）；National Astronomical Observatory of Japan（日本国立天文台）；NASA Ames Research Center（美国国家航空航天局艾姆斯研究中心）；Astrobiology Center（天体生物学中心）；Steward Observatory, University of Arizona（亚利桑那大学斯图尔德天文台）；College of Optical Sciences, University of Arizona（亚利桑那大学光学科学学院）
The Roman Coronagraph Community Participation Program: Observation planning and data reduction for polarimetric mode
Steward Observatory, University of Arizona（亚利桑那大学斯图尔德天文台）；National Astronomical Observatory of Japan, NINS（日本国立天文台）；Astrobiology Center, NINS（天体生物学中心）；Aix Marseille Univ, CNRS, CNES, LAM（艾克斯-马赛大学）；Sibley School of Mechanical and Aerospace Engineering, Cornell University（康奈尔大学）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；Caltech（加州理工学院）；The Graduate Univ. for Advanced Studies（综合研究大学院大学）；Space Telescope Science Institute（太空望远镜科学研究所）；Jet Propulsion Laboratory, California Institute of Technology（喷气推进实验室）；DM Telescopes LLC（DM望远镜有限责任公司）；Department of Astronomy, Graduate School of Science, The University of Tokyo（东京大学）；Northwestern University（西北大学）；Tellus1 Scientific, LLC（Tellus1科学有限公司）
Jointly Modeling Roman Coronagraph Astrometry and Photometry Improves Orbital Parameter Estimates
Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), Northwestern University（西北大学跨学科天体物理探索与研究中心）；Department of Physics and Engineering, University of St. Thomas（圣托马斯大学物理与工程系）；Department of Astronomy and Astrophysics, University of California, Santa Cruz（加州大学圣克鲁斯分校天文与天体物理系）
The Roman Coronagraph Community Participation Program: data reduction pipeline design and implementation
Northwestern University（西北大学）；Center for Interdisciplinary Exploration and Research in Astrophysics（天体物理学跨学科探索与研究中心）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；University of Alabama in Huntsville（阿拉巴马大学亨茨维尔分校）；University of Maryland College Park, Center for Research and Exploration in Space Science and Technology II (CRESST II), NASA GSFC（马里兰大学帕克分校，空间科学与技术研究探索中心二期（CRESST II），NASA戈达德太空飞行中心）；Steward Observatory and the Department of Astronomy, The University of Arizona（亚利桑那大学斯特沃德天文台及天文学系）；National Astronomical Observatory of Japan, NINS（日本国立天文台，NINS）；Lake Forest College（湖森林学院）；NASA’s Goddard Space Flight Center（NASA戈达德太空飞行中心）；Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France（法国马赛艾克斯-马赛大学，CNRS，CNES，LAM）；Space Telescope Science Institute（太空望远镜科学研究所）；Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ, UK（爱丁堡大学皇家天文台天文学研究所）；Caltech（加州理工学院）；DM Telescopes LLC（DM Telescopes有限责任公司）；Astrobiology Center, NINS（NINS天体生物学中心）；Sibley School of Mechanical and Aerospace Engineering, Cornell University（康奈尔大学西尔维机械工程与航空工程学校）；Department of Astronomy and Astrophysics, University（大学天文学与天体物理学系）
The Roman Coronagraph Community Participation Program: pre-launch reference star list and impact of reference star properties on post-processing performance
Steward Observatory and Department of Astronomy, University of Arizona（亚利桑那大学天文台与天文学系）；DM Telescopes LLC（DM望远镜有限责任公司）；NASA Jet Propulsion Laboratory, California Institute of Technology（加州理工学院NASA喷气推进实验室）；Institute for Astronomy, University of Edinburgh, Royal Observatory（爱丁堡大学天文研究所皇家天文台）；Centre for Exoplanet Science , University of Edinburgh（爱丁堡大学系外行星科学中心）；Université Grenoble Alpes, CNRS, IPAG（格勒诺布尔阿尔卑斯大学、法国国家科学研究中心、IPAG）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；Department of Physics and Astronomy, University of Notre Dame（圣母大学物理与天文学系）；NASA Exoplanet Science Institute, IPAC, California Institute of Technology（加州理工学院NASA系外行星科学研究所IPAC）；European Southern Observatory（欧洲南方天文台）；Bay Area Environmental Research Institute（湾区环境研究所）；Space Telescope Science Institute（太空望远镜科学研究所）；Wyant College of Optical Sciences, The University of Arizona（亚利桑那大学怀特光学科学学院）；Subaru Telescope, National Observatory of Japan, National Institutes of Natural Sciences（日本国立自然科学院日本国立天文台昴星团望远镜）；Astrobiology Center of NINS（日本国立自然科学院天体生物学中心）；Leiden Observatory, Leiden University（莱顿大学莱顿天文台）；Northrop Grumman Corporation（诺斯罗普·格鲁曼公司）；NASA Ames Research Center（NASA艾姆斯研究中心）；National Astronomical Observator（国家天文观测所）
The Roman Coronagraph Community Participation Program: calibration strategy for the Mueller matrix using on-sky sources
Astrobiology Center（天体生物学中心）；National Astronomical Observatory of Japan（日本国立天文台）；Steward Observatory and the Department of Astronomy, The University of Arizona（亚利桑那大学斯特沃德天文台及天文学系）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；Hiroshima Astrophysical Science Center, Hiroshima University（广岛大学广岛天体物理科学中心）；Department of Astronomy, Graduate School of Science, The University of Tokyo（东京大学理学研究科天文学系）；Northwestern University（西北大学）；Center for Interdisciplinary Exploration and Research in Astrophysics（天体物理学跨学科探索与研究中心）；Tellus1 Scientific, LLC（Tellus1科学有限责任公司）；Department of Astronomical Science, The Graduate University for Advanced Studies, SOKENDAI（综合研究大学院大学天文学科学研究科）
The Roman Coronagraph Community Participation Program: early calibration plan and pilot observation of a companion
Space Telescope Science Institute（太空望远镜科学研究所）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；California Institute of Technology（加州理工学院）；University of California, Santa Barbara（加州大学圣巴巴拉分校）；Tellus1 Scientific, LLC（Tellus1科学有限责任公司）；Aix Marseille Univ, CNRS, CNES, LAM（艾克斯-马赛大学、法国国家科学研究中心、法国国家空间研究中心、天体物理与行星学实验室）；Northwestern University（西北大学）；DM Telescopes LLC（DM望远镜有限责任公司）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；Astrobiology Center of NINS（日本国立自然科学研究所天体生物学中心）；National Astronomical Observatory of Japan（日本国立天文台）；The University of Alabama in Huntsville（阿拉巴马大学亨茨维尔分校）；Johns Hopkins University（约翰斯·霍普金斯大学）；NASA Ames Research Center（美国宇航局艾姆斯研究中心）；University of Edinburgh（爱丁堡大学）；University of California, Santa Cruz（加州大学圣克鲁兹分校）
On-sky dark hole diggin' with implicit Electric Field Conjugation on MagAO-X
Leiden University（莱顿大学）；The University of Arizona（亚利桑那大学）；National Observatory of Japan, National Institutes of Natural Sciences（日本国立天文台，国立自然科学研究所）；Subaru Telescope, National Observatory of Japan, National Institutes of Natural Sciences（昴星团望远镜，日本国立天文台，国立自然科学研究所）；Astrobiology Center, National Institutes of Natural Sciences（天体生物学中心，国立自然科学研究所）；Northrop Grumman Corporation（诺斯罗普·格鲁曼公司）
研究利用 MagAO-X 仪器，通过焦平面波前传感和控制，借助隐式电场共轭（iEFC）算法在观测时主动去除非共路像差（NCPA），经实验验证该方法在实际观测条件下的稳健性和效率，为下一代 AO 系统集成奠定基础。
The Nancy Grace Roman Space Telescope (Roman) is an observatory for both wide-field observations and coronagraphy that is scheduled for launch in the mid 2020's. Part of the planned survey is a deep, cadenced field or fields that enable cosmological measurements with type Ia supernovae (SNe Ia). With a pixel scale of 0".11, the Wide Field Instrument will be undersampled, presenting a difficulty for precisely subtracting the galaxy light underneath the SNe. We use simulated data to validate the ability of a forward-model code (such codes are frequently also called "scene-modeling" codes) to per…
Simulations of exoplanet albedo profiles are key to planning and interpreting future direct imaging observations. In this paper we demonstrate the use of the Planetary Spectrum Generator to produce simulations of reflected light exoplanet spectra. We use PSG to examine multiple issues relevant to all models of directly imaged exoplanet spectra and to produce sample spectra of the bright, nearby exoplanet $\upsilon$ Andromedae d, a potential direct imaging target for next-generation facilities. We introduce a new, fast, and accurate subsampling technique that enables calculations of disk-integr…
Space coronagraphs are projected to detect exoplantes that are at least 1e10 times dimmer than their host stars. Yet, the actual detection threshold depends on the instrument's wavefront stability and varies by an order of magnitude with the choice of observation strategy and post-processing method. In this paper the authors consider the performance of the previously introduced observation strategy (dark hole maintenance) and post-processing algorithm (electric field order reduction) in the presence of various realistic effects. In particular, it will be shown that under some common assumption…
