Year: 2026
Type: preprint
Abstract: Radio-interferometric images are reconstructed from sparsely sampled visibilities, and CLEAN-based imaging can struggle with spatial filtering, complex morphologies, and uncertainty quantification. Alternative methods that fit visibilities directly can address some of these limitations but often require manual choices of image priors and model hyperparameters. We present SIFARI (Self-Supervised Interferometric Fitting for Astronomical Radio Imaging), a self-supervised neural network workflow that represents sky brightness as a continuous function of position and fits measured visibilities without an external image training set or explicit spatial regularizer. An empirical rule sets the Fourier feature scale from the visibilities before training, controlling how readily the network fits fine structure. Sampling network weights with Stochastic Weight Averaging-Gaussian (SWAG) gives approximate brightness uncertainty estimates, which we combine with a thermal-noise floor to construct spatially resolved signal-to-noise maps. In synthetic ALMA tests, SIFARI yields an effective point-source response about eight times narrower than the natural-weighting CLEAN restoring beam and recovers more extended flux than CLEAN when short baselines are missing. It also achieves higher image fidelity than the restored CLEAN images in all three morphology benchmarks. Applied to ALMA observations of PDS 70, SIFARI recovers the bright outer ring together with faint compact emission in the central cavity. For long-baseline-only WISPIT 2 data, SIFARI supplies a sky model for phase self-calibration where the CLEAN model is inadequate. The restored, self-calibrated SIFARI image has approximately 30% lower RMS noise than the CLEAN image made from the original visibilities without self-calibration.
Source: arXiv (Cornell University)
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: GUIDING QUESTION: HOW TO ACQUIRE SUSTAIN AND NURTURE LIFE-ESSENTIAL CHEMICAL INGREDIENTS ON THE SURFACE OF ROCKY PLANETS? BUILDING A HABITABLE ENVIRONMENT ON INNER SOLAR SYSTEM ROCKY SURFACES REQUIRES THE LIFE-ESSENTIAL CHEMICAL INGREDIENTS (C N O H S AND P) TO JOURNEY THROUGH A SERIES OF ASTRONOMICAL PLANETARY GEOLOGICAL AND GEOCHEMICAL PROCESSES DURING PLANET FORMATION AND EARLY PLANETARY EVOLUTION. HOWEVER IN MOST STUDIES ONLY ONE OR FEW OF THESE STEPS ARE INVESTIGATED IN ISOLATION AS CONDITIONS OF HABITABILITY AND THE CONSEQUENCES OF MULTIPLE PATHWAYS THAT MAY BE FEASIBLE ARE NOT RIGOROUSLY EXPLORED. SIMILARLY MOST STUDIES TRACKING THE IMPACT OF PREBIOTIC PROCESSES CONSIDERED THE ORIGIN OF WATER ALONE AND COMPREHENSIVE STUDIES ON A COMBINATION OF LIFE-ESSENTIAL ELEMENTS ARE LACKING. IN ORDER TO EVALUATE THE PATHWAYS THAT MAY LEAD TO EARLY HABITABLE CONDITIONS IN MULTIPLE PLANETARY SURFACES BUT SUSTENANCE ONLY IN A SUBSET AN INTERDISCIPLINARY APPROACH TO STUDY THE EARLY CYCLES OF ALL KEY INGREDIENTS ARE NECESSARY. THIS CAN 8 NAI NODE PROPOSAL AIMS TO CONSTRAIN THE PATHWAYS THAT LEAD TO THE ACQUISITION SUSTENANCE AND NURTURING OF THE LIFE-ESSENTIAL CHEMICAL ELEMENTS AT THE SURFACE AND NEAR-SURFACE ENVIRONMENTS OF ROCKY DIFFERENTIATED PLANETARY BODIES LEADING TO HABITABILITY AND POTENTIALLY DRIVING THE FORMATION OF PREBIOTICALLY-RELEVANT ORGANIC MOLECULE PRECURSORS WITHIN THE FIRST BILLION YEARS OF A PLANET S EVOLUTION. OUR TEAM MEMBERS BRING EXTENSIVE EXPERTISE IN ASTROPHYSICS GEOLOGY GEOCHEMISTRY GEOPHYSICS FLUID AND ATMOSPHERIC DYNAMICS CLIMATE SCIENCE AND ORGANIC CHEMISTRY; AN OVERARCHING GOAL IS TO TRACE THE LIFE-ESSENTIAL ELEMENTS FROM PROTOPLANETARY DISKS TO EARLY PREBIOTIC MOLECULES ON THE SURFACES OF ROCKY PLANETS WITH A PARTICULAR EMPHASIS ON THE FEEDBACKS AMONG INTERIOR SURFACE AND ATMOSPHERIC PROCESSES. WE WILL USE OBSERVATIONS FROM OUR OWN SOLAR SYSTEM IN TERMS OF COMPARATIVE PLANETOLOGY BUT WILL ALSO CONSTRUCT POSSIBLE PATHWAYS THAT MAY LEAD TO THERMO-CHEMICAL HABITABILITY WHICH CAN BE UTILIZED FOR EXPLORATION OF OTHER SOLAR SYSTEMS IN SEARCH FOR LIFE. THE PROPOSED RESEARCH COMPLEMENTS THE ACTIVITIES OF THE CAN 7 TEAMS BECAUSE NONE OF THE CURRENT TEAMS ARE INVESTIGATING THE CYCLES OF THE KEY INGREDIENTS DURING DIFFERENTIATION AND EARLY TECTONO-MAGMATIC AND GEOCHEMICAL EVOLUTION OF ROCKY PLANETS. OUR PROPOSAL WILL BRING IN THE UNIQUE INTERDISCIPLINARY PERSPECTIVE OF CYCLES OF KEY INGREDIENTS OF LIFE THROUGH DEEP TIME FROM GEOLOGIC PLANETARY GEOPHYSICAL AND GEOCHEMICAL PERSPECTIVES. GIVEN THE INTERDEPENDENT NATURE OF THE PROPOSED ACTIVITIES AMONG SEEMINGLY DISPARATE FIELDS OF RESEARCH THE SCOPE OF THIS PROPOSAL CAN ONLY BE SUPPORTED THROUGH AN INSTITUTE WITHOUT WALLS . RELEVANCE TO THE GOALS OF THE ASTROBIOLOGY PROGRAM: THE PROPOSED INVESTIGATION IS RELEVANT FOR SEVERAL OF THE GOALS OF THE ASTROBIOLOGY PROGRAM AS OUTLINED IN THE 2015 STRATEGY INCLUDING THE CENTRAL THEMES OF CONSTRUCTING HABITABLE WORLDS AND IDENTIFYING EXPLORING AND CHARACTERIZING ENVIRONMENTS FOR HABITABILITY AND BIOSIGNATURES . OUR PROPOSAL WILL DIRECTLY ADDRESS QUESTIONS SUCH AS HOW DOES THE STORY OF EARTH IN PARTICULAR IT S PAST INFORM US ABOUT HOW THE CLIMATES ATMOSPHERIC COMPOSITIONS INTERIORS AND BIOSPHERES OF PLANETS CAN CO-EVOLVE? BECAUSE OUR TEAM WILL STUDY THE INTERACTIONS OF INTERIOR ATMOSPHERE AND CLIMATE IN THE FIRST BILLION YEARS OF A ROCKY PLANETS EVOLUTION KEEPING IN MIND THE HISTORY OF THE EARTH AS AN ANALOG. OUR PROPOSAL WILL ALSO DIRECTLY ADDRESS QUESTIONS SUCH AS WHAT ARE THE FUNDAMENTAL INGREDIENTS AND PROCESSES THAT DEFINE A HABITABLE ENVIRONMENT? BECAUSE WE WILL TRACK THE FATE OF THE LIFE-ESSENTIAL ELEMENTS THROUGH THE FUNDAMENTAL PROCESSES OF PLANET FORMATION AND EARLY GEOLOGIC AND BIOGEOCHEMICAL EVOLUTION WITH THE GOAL OF OUTLINING POSSIBLE PATHS THAT ARE OR ARE NOT FAVORABLE IN FINALLY HARBORING THE COHNSP SPECIES AT THE PLANETARY SURFACES., G963450986
OpenAlex ID: W7214999959