achael/eht-imaging
Eht Imaging
Este proyecto es una suite de software para imágenes de interferometría de radio, especializada en el procesamiento, análisis y reconstrucción de observaciones de interferometría de muy larga base (VLBI). Proporciona herramientas para reconstruir imágenes a partir de datos de interferometría utilizando métodos de máxima verosimilitud regularizada y gestionando el pipeline de procesamiento de datos de extremo a extremo, desde visibilidades crudas hasta imágenes finales.
El software se distingue por un simulador de dispersión interestelar dedicado que modela efectos de dispersión de pantalla delgada y aplica kernels de dispersión a imágenes de radio. También cuenta con un pipeline de síntesis de imágenes de radio capaz de generar datos VLBI sintéticos y ejecutar estudios paramétricos para optimizar las configuraciones de imagen.
El sistema cubre una amplia gama de capacidades, incluyendo la reconstrucción de imágenes polarimétricas y multifrecuencia, calibración de radioastronomía y simulación de arreglos de telescopios. Proporciona herramientas integrales de análisis de datos para distribuciones circulares, estimación de intervalos de confianza bootstrap y la generación de gráficos de resumen observacional para evaluar la fiabilidad y calidad de la imagen.
El conjunto de herramientas admite la importación de datos de radioastronomía desde formatos como FITS, UVFITS y HDF5.
Features
- Interferometric Image Reconstruction - Produces radio images from interferometry data sets using regularized maximum likelihood methods.
- Interstellar Scattering Simulators - Models thin-screen scattering effects and phase fluctuations to simulate interstellar medium interference on radio images.
- Regularized Reconstruction - Produces radio images by minimizing a cost function that balances data fidelity with image smoothness.
- Multi-frequency Reconstruction - Generates images from interferometric data sets using regularized maximum likelihood methods and multi-frequency spectral indexing.
- Polarimetric Reconstruction - Produces images from radio interferometry data sets using regularized maximum likelihood methods across various polarizations.
- Pigment Scattering Simulators - Provides a specialized toolkit for modeling thin-screen scattering effects and applying scattering kernels to radio images.
- Data Processing and Analytics - Provides a system for calibrating, manipulating, and analyzing Very Long Baseline Interferometry observations and visibility data.
- Array Configurations - Configures collections of ground stations and antennas using site locations, SEFD values, and orbital elements.
- Interferometry Data Pipelines - Processes radio observations through a sequence of flagging, calibration, and tapering before image transformation.
- Interferometry Self-Calibration - Corrects observational data through self-calibration and network calibration to improve the fidelity of resulting images.
- VLBI Data Processing - Loads, calibrates, and manipulates Very Long Baseline Interferometry data sets to ensure high data accuracy and quality.
- Data Format Importers - Supports importing specialized radio astronomy formats such as FITS, UVFITS, and HDF5 into processing objects.
- Radio Calibration Tools - Loads, calibrates, inspects, and plots radio interferometry data sets and calibration tables.
- Interferometric Calibration - Corrects observation data through self-calibration and network calibration to improve the fidelity of reconstructed images.
- Radio - Offers a comprehensive suite for reconstructing astronomical images from radio interferometry data using regularized maximum likelihood.
- Astro-Image Reliability Analysis - Computes circular means, standard deviations, and bootstrap samples to evaluate the reliability of reconstructed images.
- Interferometric Visibility Representations - Stores polarimetric visibility amplitudes and phases along with source coordinates and frequency metadata.
- Interferometry Data Calibration - Corrects observation data using interpolation or extrapolation from calibration tables to ensure high data accuracy.
- Interferometry Data Pre-processing - Implements pre-imaging calibration, including site flagging, baseline rescaling, and tapering of radio observations.
- Interstellar Scattering Models - Simulates interstellar scattering by applying Fourier-domain phase fluctuations and scattering kernels to visibilities.
- Interstellar Scattering Simulation - Simulates the effects of a thin-screen scattering model using power spectra to define phase fluctuations.
- Multi-Frequency Spectral Indexing - Incorporates frequency-dependent intensity changes into the reconstruction process to produce wide-band radio images.
- Observational Dataset Generation - Calculates points and baseline uncertainties using source coordinates and station constraints to produce accurate observation sets.
- Radio Interferometry Imaging - Produces high-resolution images from radio telescope data using regularized maximum likelihood methods and spectral indexing.
- Confidence Interval Calculators - Calculates bootstrap estimates of confidence intervals for statistics, including specialized handling for circular variables.
- Parametric Survey Execution - Executes automated batches of imaging runs across predefined parameter configurations to optimize the resulting output.
- Polarimetric Sequence Synthesis - Constructs time-sequenced series of polarimetric images with defined spatial dimensions and frequency metadata.
- Astronomy - Provides a library for computing polarimetric flux, circular statistics, and bootstrap confidence intervals for astronomical data.
- Calibration Table Merging - Combines multiple calibration tables into a single dataset using specified interpolation and extrapolation settings.
- Observation Schedule Parsing - Extracts station coordinates and timing metadata from VEX schedules to define telescope array geometry.
- Imaging Pipeline Orchestration - Coordinates the loading of data files, prior image creation, and exportation of results for multiple parameter sets.
- Parametrized Command Execution - Executes batches of imaging runs by injecting different parameter sets to analyze the impact on results.
- Atmospheric Scattering - Models the impact of interstellar scattering on radio images using epsilon screens and scattering models.
- Radio Scattering Blurs - Applies a scattering kernel to an image to simulate the effect of interstellar scattering at a specific wavelength.
- Scattering Screen Synthesis - Creates a standardized Fourier representation of a scattering screen using a specified resolution and random seed.
- Polarimetric Data Generation - Generates representations of radio interferometry data including coordinates, frequency, and polarization states.
- Interferometric Deblurring - Removes interstellar scattering effects from observation data by dividing visibilities by an ensemble-average scattering kernel.
- Analytic Source Modeling - Generates geometric representations of radio sources using shapes like disks and Gaussians.
- Astronomical Observation Summaries - Produces detailed polarimetric summary plots including D-terms and fractional polarization data to evaluate image quality.
- Circular Distribution Analysis - Computes the mean and standard deviation for angular quantities to account for the wrapping nature of circular data.
- Circular Statistical Analysis - Implements specialized wrapping logic to calculate means and standard deviations for angular radio data.
- Interferometric Array Simulators - Generates synthetic interferometric data and analytic models to test detection capabilities and telescope configurations.
- Interferometric Quality Metrics - Calculates and exports chi-squared values for closure phase and visibility to evaluate reconstructed image quality.
- Interferometry Summary Plotting - Creates PDF summaries of radio interferometry images, including gain, amplitude, and closure phase consistency plots.
- Bootstrap Confidence Estimation - Provides bootstrap-based confidence interval estimation to quantify uncertainty in imaging statistics.
- Observational Data Visualization - Visualizes differences between observed data, models, and produced images through a suite of plotting tools.
- Polarimetric Radio Analysis - Generates and analyzes radio images including frequency, polarization states, and circular polarized flux over time.
- Radio Image Synthesis Pipelines - Provides a framework for generating synthetic VLBI data and executing parametric surveys to optimize imaging configurations.
- Telescope Sensitivity Normalization - Rescales gain curves using mean, median, or minimum methods to keep site sensitivities above specified thresholds.
- Time-Averaged Property Calculation - Computes derived products like visibility amplitudes and closure phases using specified averaging timescales.
- Unbiased Amplitude Estimation - Calculates the unbiased amplitude from an ensemble of Rice-distributed or visibility measurements using debiasing techniques.
- VLBI Data Simulation - Generates simulated interferometric data from existing images, including time-variable data based on real tracks.
