Conveners
Thursday afternoon: Data Science & Imaging
- Emma Tolley (EPFL)
Thursday afternoon: Science Enabling Tools
- Simon Felix (FHNW)
In this work, we apply a novel approach for the reconstruction of radio astronomy images from uv-observations using guided diffusion. We use the Common Astronomy Software Applications package (CASA) to simulate data from Atacama Large Millimeter Array (ALMA). Our approach is based on denoising diffusion probabilistic models (DDPMs), which are effective at capturing the prior distribution given...
Self-supervised techniques which leverage very large datasets have become standard in computer vision research, yet they are only now being applied to astrophysics. A major limitation is the characteristics of the data. In radio astronomy, flux values span a large dynamic range, and even the reduced size of the data in the image plane can be much larger than is typically used in computer...
Bluebild is a next generation radio interferometric imager that reconstructs images directly on the celestial sphere. It does so by decomposing the captured visibilities into a set of eigenvalue-weighted eigen-visibilities via fPCA. We present updates on the scientific validation and development of this algorithm.
Analysis and synthesis are key steps of the radio-interferometric imaging process, serving as a bridge between the visibility and sky domain. They can be expressed as partial Fourier transforms involving a large number of non-uniform frequencies and spherically-constrained spatial coordinates. Due to the data non-uniformity, these partial Fourier transforms are computationally expensive and...
KARABO is a versatile data simulator designed to handle the complex scientific requirements of the Square Kilometre Array (SKA) data. The simulator uses containerized packages and science-specific Python modules to generate mock data that allows for the study of scientific accuracy and the characterization of the instrument. KARABO's flexibility and parallelization make it a powerful tool for...
Neutral hydrogen (HI) intensity mapping makes it possible to
probe large volumes of the Universe. Since fluctuations of HI are a tracer for dark matter fluctuations, we can reconstruct the dark matter density field from HI intensity mapping. For HI intensity mapping systematics are a significant concern, therefore we need simulations to get a good understanding of their effects on the data....
We present Karabo user stories to demonstrate how we support science use cases. We talk about past examples where and how users requestes features, and what happened next.
The cosmic epoch of reionization (EoR) is studied using Radiative Transfer (RT) codes that simulate the radiative feedback from primordial galaxies and stars in the early Universe. This includes the simulation of the evolution of the neutral hydrogen fraction and thermal properties of the intergalactic medium (IGM) due to the computed ionizing and heating radiation. These simulations...
The processing of a significant amount of data generated by the Square Kilometre Array (SKA) radio telescopes to produce scientific data products for answering complex radio astronomical questions requires high-performance supercomputers. However, the Science Data Processors (SDPs), which are one of the primary processing facilities of SKA, have limited power resources. Thus, it is crucial to...
