Statistical characterization and classification of astronomical transients with Machine Learning in the era of the Vera C. Rubin Observatory
M. Vicedomini, M. Brescia, S. Cavuoti, G. Longo, G. Riccio
备注：
Preprint version of the manuscript to appear in the Volume "Intelligent Astrophysics" of the series "Emergence, Complexity and Computation", Book eds. I. Zelinka, D. Baron, M. Brescia, Springer Nature Switzerland, ISSN: 2194-7287
Astronomy has entered the multi-messenger data era and Machine Learning has found widespread use in a large variety of applications. The exploitation of synoptic (multi-band and multi-epoch) surveys, like LSST (Legacy Survey of Space and Time), requires an extensive use of automatic methods for data processing and interpretation. With data volumes in the petabyte domain, the discrimination of time-critical information has already exceeded the capabilities of human operators and crowds of scientists have extreme difficulty to manage such amounts of data in multi-dimensional domains. This work is focused on an analysis of critical aspects related to the approach, based on Machine Learning, to variable sky sources classification, with special care to the various types of Supernovae, one of the most important subjects of Time Domain Astronomy, due to their crucial role in Cosmology. The work is based on a test campaign performed on simulated data. The classification was carried out by comparing the performances among several Machine Learning algorithms on statistical parameters extracted from the light curves. The results make in evidence some critical aspects related to the data quality and their parameter space characterization, propaedeutic to the preparation of processing machinery for the real data exploitation in the incoming decade.
The Vera C. Rubin Observatory Prompt Processing System
University of Washington, Seattle, WA, USA（华盛顿大学）；SLAC National Accelerator Laboratory, Menlo Park, CA, USA（SLAC国家加速器实验室）；Burwood Group, Oak Brook, IL, USA（伯伍德集团）
该研究介绍了Vera C. Rubin Observatory的即时处理系统如何满足高吞吐量、低延迟和高可靠性的要求，并展示了观测站的调试结果。
The Legacy Survey of Space and Time, operated by the Vera C. Rubin Observatory, is a 10-year astronomical survey due to start operations in 2022 that will image half the sky every three nights. LSST will produce ~20TB of raw data per night which will be calibrated and analyzed in almost real time. Given the volume of LSST data, the traditional subset-download-process paradigm of data reprocessing faces significant challenges. We describe here, the first steps towards a gateway for astronomical science that would enable astronomers to analyze images and catalogs at scale. In this first step we …
The Vera Rubin Observatory, set to begin observations in mid-2024, will increase our discovery rate of supernovae to well over one million annually. There has been a significant push to develop new methodologies to identify, classify and ultimately understand the millions of supernovae discovered with the Rubin Observatory. Here, we present the first simulation-based inference method using normalizing flows, trained to rapidly infer the parameters of toy supernovae model in multivariate, Rubin-like datastreams. We find that our method is well-calibrated compared to traditional inference method…
Early Telescope Throughput Results from the Collimated Beam Projector at the Vera C. Rubin Observatory
Laboratoire d’Annecy de Physique des Particules (LAPP)（巴黎-萨克雷大学粒子物理实验室）；NSF’s NOIRLab（美国国家光学红外天文实验室）；SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Laboratoire Irène Joliot-Curie (IJCLab)（伊雷娜·约里奥-居里实验室）；Kavli Institute for Particle Astrophysics & Cosmology (KIPAC)（卡弗里粒子天体物理与宇宙学研究所）；Department of Physics, Harvard University（哈佛大学物理系）
The Rubin Observatory's Data Butler is designed to allow data file location and file formats to be abstracted away from the people writing the science pipeline algorithms. The Butler works in conjunction with the workflow graph builder to allow pipelines to be constructed from the algorithmic tasks. These pipelines can be executed at scale using object stores and multi-node clusters, or on a laptop using a local file system. The Butler and pipeline system are now in daily use during Rubin construction and early operations.
Vera C. Rubin Observatory will be a key facility for small body science in planetary astronomy over the next decade. It will carry out the Legacy Survey of Space and Time (LSST), observing the sky repeatedly in u, g, r, i, z, and y over the course of ten years using a 6.5 m effective diameter telescope with a 9.6 square degree field of view, reaching approximately r = 24.5 mag (5-σ depth) per visit. The resulting dataset will provide extraordinary opportunities for both discovery and characterization of large numbers (10--100 times more than currently known) of small solar system bodies, furth…
The presence of fringing in astronomical CCD images will impact photometric quality and measurements. Yet its impact on the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) has not been fully studied. We present a detailed study on fringing for Charge-Coupled Devices (CCDs) already implemented on the Rubin Observatory LSST Camera's focal plane. After making physical measurements and knowing the compositions, we have developed a model for the e2v CCDs. We present a method to fit for the internal height variation of the epoxy layer within the sensors based on fringing measureme…
With their emission mainly coming from a relativistic jet pointing towards us, blazars are fundamental sources to study extragalactic jets and their central engines, consisting of supermassive black holes (SMBHs) fed by accretion discs. They are also candidate sources of high-energy neutrinos and cosmic rays. Because of the jet orientation, the non-thermal blazar emission is Doppler beamed; its variability is unpredictable and occurs on time-scales from less than one hour to years. The comprehension of the diverse mechanisms producing the flux and spectral changes requires well-sampled multiba…
Laser-based metrology systems vs wavefront sensing techniques: a comparative overview between the Large Binocular Telescope and the Vera C. Rubin Observatory for the telescope alignment and collimation tracking
INAF Osservatorio di Astrofisica e Scienza dello Spazio（意大利国家天体物理研究所空间天体物理与科学观测站）；Vera C. Rubin Observatory Project Office（薇拉·C·鲁宾天文台项目办公室）；California Institute of Technology（加州理工学院）；Wyant College of Optical Sciences, University of Arizona（亚利桑那大学怀安特光学科学学院）；Large Binocular Telescope Observatory, University of Arizona（亚利桑那大学大双筒望远镜天文台）；DIRAC Institute, University of Washington（华盛顿大学迪拉克研究所）；Department of Astronomy, University of Washington（华盛顿大学天文学系）；Department of Physics, Duke University（杜克大学物理学系）；Observatorio Astrofisico di Arcetri（阿尔切特里天体物理观测站）；Vera C. Rubin Observatory（薇拉·C·鲁宾天文台）；Department of Astrophysical Sciences, Princeton University（普林斯顿大学天体物理科学系）；INAF OATS（意大利国家天体物理研究所的奥阿斯特天文台）；INAF IASF（意大利国家天体物理研究所的星际介质和天体物理学研究所）；Department of Physics “E. Pancini”, University Federico II of Napoli（那不勒斯费德里科二世大学“E.潘奇尼”物理学系）；Harvard Physics Department（哈佛大学物理学系）；Vera C Rubin Observatory/NOIRLab（薇拉·C·鲁宾天文台/美国国家光学红外天文实验室）；Department of Physics, Stanford University（斯坦福大学物理学系）；SLAC National Accelerator Laboratory（斯坦福直线加速器中心）
Test Management and Coordination During the Vera C. Rubin Observatory Commissioning and Early Operations Using Zephyr Scale
NSF–DOE Vera C. Rubin Observatory/NSF NOIRLab（美国国家科学基金会-能源部薇拉·C·鲁宾天文台/美国国家光学红外天文实验室）；Department of Physics, University of Wisconsin-Madison（威斯康星大学麦迪逊分校物理系）
The commissioning team for the Vera C. Rubin observatory is planning a set of engineering and science verification observations with the Legacy Survey of Space and Time (LSST) commissioning camera and then the Rubin Observatory LSST Camera. The time frame for these observations is not yet fixed, and the commissioning team will have flexibility in selecting fields to observe. In this document, the Dark Energy Science Collaboration (DESC) Commissioning Working Group presents a prioritized list of target fields appropriate for testing various aspects of DESC-relevant science performance, grouped …
Extracting Asteroid Physical Properties from Vera C. Rubin Observatory Science Validation Survey Data: Rotational Periods, Colors, and Taxonomies
São Paulo State University (UNESP)（圣保罗州立大学）；Laboratório Interinstitucional de e-Astronomia（跨机构电子天文实验室）；NSF–DOE Vera C. Rubin Observatory / NSF NOIRLab（美国国家科学基金会-能源部薇拉·C·鲁宾天文台/美国国家科学基金会NOIRLab）；DiRAC Institute and the Department of Astronomy, University of Washington（华盛顿大学天文学系及DiRAC研究所）；Instituto de Astronomía y Ciencias Planetarias, Universidad de Atacama（阿塔卡马大学天文与行星科学研究所）；Universidad Tecnológica del Perú (UTP)（秘鲁理工大学）
Skykatana: a scalable framework to construct sky masks for the Vera Rubin Observatory and large astronomical surveys
Instituto de Ciencias Astronómicas, de la Tierra y del Espacio (ICATE), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)（地球与空间天文科学研究所 (ICATE)，阿根廷国家科学研究委员会 (CONICET)）；Facultad de Ciencias Exactas, Físicas y Naturales (FCEFYN-UNSJ), Universidad Nacional de San Juan（圣胡安国立大学精确、物理与自然科学学院 (FCEFYN-UNSJ)）；Instituto de Astronomía Teórica y Experimental (IATE), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)（理论与实验天文学研究所 (IATE)，阿根廷国家科学研究委员会 (CONICET)）；Observatorio Astronómico Córdoba , Universidad Nacional de Córdoba（科尔多瓦天文台，科尔多瓦国立大学）
Joint multiband deconvolution for Euclid and Vera C. Rubin images
Laboratory of Astrophysics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Observatoire de Sauverny（天体物理实验室，瑞士洛桑联邦理工学院（EPFL），萨瓦尼观测站）；GEPI, Observatoire de Paris, Université PSL, CNRS（GEPI，巴黎天文台，巴黎-萨克勒大学，国家科学研究中心）；ICC-UB Institut de Ciències del Cosmos, Universitat de Barcelona（ICC-UB宇宙科学研究所，巴塞罗那大学）；ICREA, Pg. Lluís Companys 23, Barcelona（ICREA，巴塞罗那路易斯·康帕尼斯街23号）；Université Paris-Saclay, Université Paris Cité, CEA, CNRS, AIM（巴黎-萨克勒大学，巴黎城市大学，法国原子能委员会，国家科学研究中心，应用数学研究所）；Institutes of Computer Science and Astrophysics, Foundation for Research and Technology Hellas (FORTH), Greece（计算机科学与天体物理学研究所，希腊希腊研究与技术基金会（FORTH））
We investigate the possibility that a statistical detection of the galaxy parallax shift due to the Earth's motion with respect to the CMB frame (cosmic secular parallax) could be made by the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) or by the Nancy Grace Roman Space Telescope (NGRST), and used to measure the Hubble constant. We make mock galaxy surveys which extend to redshift z=0.06 from a large N-body simulation, and include astrometric errors from the LSST and NGRST science requirements, redshift errors and peculiar velocities. We include spectroscopic redshifts for …
The limiting temporal resolution of a time-domain survey in detecting transient behavior is set by the time between observations of the same sky area. We analyze the distribution of visit separations for a range of Vera C. Rubin Observatory cadence simulations. Current simulations are strongly peaked at the 22 minute visit pair separation and provide effectively no constraint on temporal evolution within the night. This choice will necessarily prevent Rubin from discovering a wide range of astrophysical phenomena in time to trigger rapid followup. We present a science-agnostic metric to supple…
We present the Strong Lensing Science Collaboration's (SLSC) recommended observing targets for the science verification and science validation phases of commissioning. Our recommendations have been developed in collaboration with the Dark Energy Science Collaboration (DESC) Strong Lensing Topical Team. In summary, our key recommendations are as follows: (1) Prioritize fields that span the full range of declination observable from Cerro Pachon during the engineering focused Science Verification phase of commissioning, before concentrating on equatorial fields for the Science Validation surveys.…
Prospects for Astrobiology and Technosignature Searches with the Vera C. Rubin Observatory Legacy Survey of Space and Time
University of Belgrade（贝尔格莱德大学）；School of Physics and Astronomy, University of Kent（肯特大学物理与天文学院）；Fermi National Accelerator Laboratory（费米国家加速器实验室）；Department of Astronomy and Astrophysics, University of Chicago（芝加哥大学天体物理学系）
We investigate a novel satellite avoidance strategy to mitigate the impact of large commercial satellite constellations in low-Earth orbit on the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST). We simulate the orbits of currently planned Starlink and OneWeb constellations ($\sim$40,000 satellites) to test how effectively an upgraded Rubin scheduler algorithm can avoid them, and assess how the overall survey is affected. Given a reasonably accurate satellite orbit forecast, we find it is possible to adjust the scheduler algorithm to effectively avoid some satellites. Overall, …
Upcoming surveys such as the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) will detect up to 10 million time-varying sources in the sky every night for ten years. This information will be transmitted in a continuous stream to brokers that will select the most promising events for a variety of science cases using machine learning algorithms. We study the benefits and challenges of Bayesian Neural Networks (BNNs) for this type of classification tasks. BNNs are found to be accurate classifiers which also provide additional information: they quantify the classification uncertain…
Modeling of the diffuse background produced by the Vera C. Rubin Observatory M2 baffle scattered light
INAF OAS（意大利国家天体物理研究所观测台）；University of Bologna（博洛尼亚大学）；University of Chicago（芝加哥大学）；Fermi National Accelerator Laboratory（费米国家加速器实验室）；SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Vera C. Rubin Observatory Project Office（薇拉·C·鲁宾天文台项目办公室）；Harvard University（哈佛大学）；NSF-DOE Vera C. Rubin Observatory / NSF NOIRLab（美国国家科学基金会-能源部薇拉·C·鲁宾天文台/美国国家光学红外天文研究实验室）；Princeton University（普林斯顿大学）；Kavli Institute of Cosmological Physics, University of Chicago（芝加哥大学卡弗里宇宙物理学研究所）；Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory（斯坦福直线加速器中心卡弗里粒子天体物理学与宇宙学研究所）；University of Washington（华盛顿大学）；Centre for Astrophysics Research, University of Hertfordshire（赫特福德大学天体物理研究中心）；INAF OATS（意大利国家天体物理研究所的里雅斯特观测台）；INAF IASF（意大利国家天体物理研究所太空天体物理研究所）；University Federico II of Napoli（那不勒斯斐迪南二世大学）；Duke University（杜克大学）
GOATS: The next generation software infrastructure for time-domain astronomy at Gemini/NOIRLab. Application to alerts from Vera C. Rubin Observatory's Legacy Survey of Space and Time
Multi-Method Machine Learning Classification of Astronomical Sources with Rubin Data Previews: a Spectroscopy-Free Approach with DP1 and DP2
SLAC National Accelerator Laboratory（SLAC国家加速器实验室）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（斯坦福大学卡弗里粒子天体物理与宇宙学研究所）；Instituto de Estudios Astrofísicos, Facultad de Ingeniería y Ciencias, Universidad Diego Portales（迭戈波特莱斯大学工程与科学学院天体物理研究所）；Department of Astrophysical Sciences, Princeton University（普林斯顿大学天体科学系）；NSF National Optical-Infrared Astronomy Research Laboratory（美国国家光学-红外天文研究实验室）；NSF–DOE Vera C. Rubin Observatory/NSF NOIRLab（美国国家科学基金会-能源部维拉·C·鲁宾天文台/美国国家科学基金会NOIRLab）
We report studies on the mitigation of optical effects of bright low-Earth-orbit (LEO) satellites on Vera C. Rubin Observatory and its Legacy Survey of Space and Time (LSST). These include options for pointing the telescope to avoid satellites, laboratory investigations of bright trails on the Rubin Observatory LSST camera sensors, algorithms for correcting image artifacts caused by bright trails, experiments on darkening SpaceX Starlink satellites, and ground-based follow-up observations. The original Starlink v0.9 satellites are g ~ 4.5 mag, and the initial experiment "DarkSat" is g ~ 6.1 ma…
Perhaps the most exciting promise of the Rubin Observatory Legacy Survey of Space and Time (LSST) is its capability to discover phenomena never before seen or predicted from theory: true astrophysical novelties, but the ability of LSST to make these discoveries will depend on the survey strategy. Evaluating candidate strategies for true novelties is a challenge both practically and conceptually: unlike traditional astrophysical tracers like supernovae or exoplanets, for anomalous objects the template signal is by definition unknown. We present our approach to solve this problem, by assessing s…
Development of a Retrieval-Augmented Generation Virtual Assistant for Enhanced Information Discovery at Rubin Observatory
NSF-DOE Vera C. Rubin Observatory / NSF NOIRLab（美国国家科学基金会-能源部薇拉·C·鲁宾天文台 / 美国国家光学红外天文研究实验室）；University of Washington（华盛顿大学）；California Institute of Technology（加州理工学院）；D4D CONSULTING LTD.（D4D咨询有限公司）；Swinburne University of Technology（斯威本科技大学）；Australian Astronomical Optics, Macquarie University（澳大利亚天文光学，麦考瑞大学）；Department of Astronomy, Center for Astrophysics, Harvard University（哈佛大学天文学系，天体物理中心）；Center for Astrophysics, Harvard & Smithsonian（哈佛-史密森尼天体物理中心）；Department of Physics, Harvard University（哈佛大学物理系）
Vera C. Rubin Observatory is a ground-based astronomical facility under construction, a joint project of the National Science Foundation and the U.S. Department of Energy, designed to conduct a multi-purpose 10-year optical survey of the southern hemisphere sky: the Legacy Survey of Space and Time. Significant flexibility in survey strategy remains within the constraints imposed by the core science goals of probing dark energy and dark matter, cataloging the Solar System, exploring the transient optical sky, and mapping the Milky Way. The survey's massive data throughput will be transformation…
The Rubin Observatory Target-of-Opportunity System in the First Year of Operations
University of Zurich（苏黎世大学）；University of Washington（华盛顿大学）；NSF-DOE Vera C. Rubin Observatory / NSF NOIRLab（美国国家科学基金会-能源部薇拉·C·鲁宾天文台/美国国家光学红外天文研究实验室）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（斯坦福大学卡弗里粒子天体物理学与宇宙学研究所）；Stanford University（斯坦福大学）；SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Princeton University（普林斯顿大学）；University of Pittsburgh（匹兹堡大学）；Fermi National Accelerator Laboratory（费米国家加速器实验室）；University of Illinois（伊利诺伊大学）；University of Delaware（特拉华大学）；Joint Space-Science Institute, University of Maryland（马里兰大学联合空间科学研究所）；Aix Marseille Université（艾克斯-马赛大学）；CNRS/IN2P3, CPPM（法国国家科学研究中心/欧洲核子研究组织粒子物理研究所，普罗旺斯粒子与宇宙学物理中心）
The Vera C. Rubin Observatory will advance many areas of astronomy over the next decade with its unique wide-fast-deep multi-color imaging survey, the Legacy Survey of Space and Time (LSST). The LSST will produce approximately 20TB of raw data per night, which will be automatically processed by the LSST Science Pipelines to generate science-ready data products -- processed images, catalogs and alerts. To ensure that these data products enable transformative science with LSST, stringent requirements have been placed on their quality and scientific fidelity, for example on image quality and dept…
