A Cloud-native Agile approach to cyber platform prototyping and integration for astronomy: the ENGAGE SKA case

The next generation interferometric radio telescope, the Square Kilometre Array (SKA), which will be the most sensitive and largest radio telescope ever constructed, could greatly contribute to the detection, survey and characterization of Gamma Ray Bursts (GRBs). By the SKA, it will be possible to perform the follow up of GRBs even for several months. This approach would be extremely useful to extend the Spectrum Energetic Distribution (SED) from the gamma to the to radio band and would increase the number of radio detectable GRBs. In principle, the SKA could help to understand the physics of GRBs by setting constraints on theoretical models. This goal could be achieved by taking into account multiple observations at different wavelengths in order to obtain a deeper insight of the sources. Here, we present an estimation of GRB radio detections, showing that the GRBs can really be observed by the SKA. The approach that we present consists in determining blind detection rates derived by a very large sample consisting of merging several GRB catalogues observed by current missions as Swift, Fermi, Agile and INTEGRAL and by previous missions as BeppoSAX, CGRO, GRANAT, HETE-2, Ulysses and Wind. The final catalogue counts 7516 distinct sources. We compute the fraction of GRBs that could be observed by the SKA at high and low frequencies, above its observable sky. Considering the planned SKA sensitivity and through an extrapolation based on previous works and observations, we deduce the minimum fluence in the range 15-150 keV. This is the energy interval where a GRB should emit to be detectable in the radio band by the SKA. Results seem consistent with observational capabilities.

The Square Kilometre Array (SKA) project is responsible for developing the SKA Observatory, the world’s largest radio telescope, with eventually over a square kilometre of collecting area and including a general headquarters as well as two radio telescopes: SKA1-Mid in South Africa and SKA1-Low in Australia. The SKA project consists of a number of subsystems (elements) among which the Telescope Manager (TM) is the one involved in controlling and monitoring the SKA telescopes. The TM element has three primary responsibilities: management of astronomical observations, management of telescope hardware and software subsystems, management of data to support system operations and all stakeholders (operators, maintainers, engineers and science users) in achieving operational, maintenance and engineering goals. Operators, maintainers, engineers and science users will interact with TM via appropriate user interfaces (UI). The TM UI framework envisaged is a complete set of general technical solutions (components, technologies and design information) for implementing a generic computing system (UI platform). Such a system will enable UI components to be instantiated to allow for human interaction via screens, keyboards, mouse and to implement the necessary logic for acquiring or deriving the information needed for interaction. It will provide libraries and specific Application Programming Interfaces (APIs) to implement operator and engineer interactive interfaces. This paper will provide a status update of the TM UI framework, UI platform and UI components design effort, including the technology choices, and discuss key challenges in the TM UI architecture, as well as our approaches to addressing them.

The Square Kilometre Array (SKA) is an ambitious project to build the world’s largest radio telescope, eventually reaching one square kilometre in collecting area. The first phase of the project, SKA1, will consist of two telescopes: SKA1-LOW, comprising ~131,000 dipole antennas at the Murchison Radio Observatory in Western Australia covering the range 50–350 MHz, and SKA1-MID, comprising ~200 x 15-m dishes in the Karoo desert in South Africa covering the range 0.35–13.8 GHz. SKA1 is scheduled to commence operations in 2023 and, in order to appropriately influence the design of the system, operational planning has commenced. This paper presents an overview of the operational concept for SKA1.

The Square Kilometre Array Observatory (SKAO) will construct two radio telescopes: SKA-Low in Australia and SKA-Mid in South Africa. When completed, the Square Kilometer Array (SKA) will be the largest radio telescope on Earth, with unprecedented sensitivity and scientific capability. The first phase of SKA-Mid (called SKA1-Mid) includes an array of 197 dish antennas incorporating the recently completed MeerKAT dishes to cover the frequency range of 350 MHz to 15.4 GHz. The 19 Tb / s digitized data stream is transported from the dishes in the remote Karoo to Cape Town where data are correlated and processed through high-performance computing systems. The demanding scientific performance requires extremely accurate timing and synchronization of the data measured by the distributed dishes. The combination of large-scale deployment, significant real-time processing, geographic distribution, and limited budget poses significant challenges for the physical, control, and processing architectures. We present the architectural highlights of the SKA1-Mid Telescope baseline design, for which its Critical Design Review was completed in 2019 and construction was started in July 2021.

As the largest radio telescope in the world, the Square Kilometre Array (SKA) will lead the next generation of radio astronomy. The feats of engineering required to construct the telescope array will be matched only by the techniques developed to exploit the rich scientific value of the data. To drive forward the development of efficient and accurate analysis methods, we are designing a series of data challenges that will provide the scientific community with high-quality data sets for testing and evaluating new techniques. In this paper, we present a description and results from the first such Science Data Challenge 1 (SDC1). Based on SKA MID continuum simulated observations and covering three frequencies (560, 1400, and 9200 MHz) at three depths (8, 100, and 1000 h), SDC1 asked participants to apply source detection, characterization, and classification methods to simulated data. The challenge opened in 2018 November, with nine teams submitting results by the deadline of 2019 April. In this work, we analyse the results for eight of those teams, showcasing the variety of approaches that can be successfully used to find, characterize, and classify sources in a deep, crowded field. The results also demonstrate the importance of building domain knowledge and expertise on this kind of analysis to obtain the best performance. As high-resolution observations begin revealing the true complexity of the sky, one of the outstanding challenges emerging from this analysis is the ability to deal with highly resolved and complex sources as effectively as the unresolved source population.

In this work, we investigate what role the redshift-drift data of the Square Kilometre Array (SKA) will play in the cosmological parameter estimation in the future. To test the constraint capability of the redshift-drift data of SKA-only, the Lambda CDM model is chosen as a reference model. We find that using the SKA1 mock data, the Lambda CDM model can be loosely constrained, while the model can be well constrained when the SKA2 mock data are used. When the mock data of SKA are combined with the data of the European Extremely Large Telescope (E-ELT), the constraints can be significantly improved, becoming almost as good as the data combination of the type Ia supernovae observation (SN), the cosmic microwave background observation (CMB), and the baryon acoustic oscillations observation (BAO). Furthermore, we explore the impact of the redshift-drift data of SKA on the basis of SN+CMB+BAO+E-ELT in the Lambda CDM model, the wCDM model, the CPL model, and the HDE model. We find that the redshift-drift measurement of SKA could help to significantly improve the constraints on dark energy and could break the degeneracy between the cosmological parameters. Therefore, we conclude that redshift-drift observation of SKA would provide a good improvement in the cosmological parameter estimation in the future and has the enormous potential to be one of the most competitive cosmological probes in constraining dark energy.

Fast radio bursts (FRBs) are mysterious extragalactic radio signals. Revealing their origin is one of the central foci in modern astronomy. Previous studies suggest that occurrence rates of non-repeating and repeating FRBs could be controlled by the cosmic stellar-mass density (CSMD) and cosmic star formation-rate density (CSFRD), respectively. The Square Kilometre Array (SKA) is one of the best future instruments to address this subject due to its high sensitivity and high-angular resolution. Here, we predict the number of FRBs to be detected with the SKA. In contrast to previous predictions, we estimate the detections of non-repeating and repeating FRBs separately, based on latest observational constraints on their physical properties including the spectral indices, FRB luminosity functions, and their redshift evolutions. We consider two cases of redshift evolution of FRB luminosity functions following either the CSMD or CSFRD. At $z$ ≳ 2, $z$ ≳ 6, and $z$ ≳ 10, non-repeating FRBs will be detected with the SKA at a rate of ∼104, ∼102, and ∼10 (sky−1 d−1), respectively, if their luminosity function follows the CSMD evolution. At $z$ ≳ 1, $z$ ≳ 2, and $z$ ≳ 4, sources of repeating FRBs will be detected at a rate of ∼103, ∼102, and ≲10 (sky−1 d−1), respectively, assuming that the redshift evolution of their luminosity function is scaled with the CSFRD. These numbers could change by about one order of magnitude depending on the assumptions on the CSMD and CSFRD. In all cases, abundant FRBs will be detected by the SKA, which will further constrain the luminosity functions and number density evolutions.

Data rates from the Square Kilometre Array will be huge, rivalling the sum total of current global internet traffic. This deluge of data prompts a demand for significant progress in techniques for signal processing, data analysis and time-series modelling of vast data sets. Developing novel, real-time, machine learning algorithms is paramount if the SKA project is to meet its science objectives [1]. As a case study in SKA data analysis, this paper outlines some intrinsic difficulties in the search for binary pulsars, briefly describes known techniques for binary pulsar detection and proposes new detection approaches. Our current focus is to model more accurately sources of non-Gaussian, non-stationary noise in a typical pulsar search. Any solution must be scalable, to satisfy the real-time requirement of the SKA pulsar surveys.

This paper will report on the progress in the research field of radio astronomy in Malaysia and also in South-East Asia. Radio astronomy research can be said to have only started being done actively in Malaysia in 2005. Fundamental setup and some basic research were done in the early parts. Jupiter radio bursts as well as radio meteor counting were the first few projects. Currently a medium-sized radio telescope which was recently purchased is being used to undergo more advanced research such as observing spectrum of galaxy clusters in order to study Dark Matter. This paper will also report on the latest results on the survey of Radio Frequency Interference (RFI), which is currently done on chosen candidate sites in Malaysia in order to setup on it a large radio telescope in the future. The best site with the lowest averaged RFI level is found at Langkawi (−100.33 dBm or 4.4 × 106 Jy). The author is the chair for the Radio Astronomy Working Group for the South-East Asia Astronomy Network (SEAAN) and the Malaysian team is very much an important part of this group. This group will eventually be a research hub for the global projects of the Global-Very Long Baseline Interferometer (Global-VLBI) and the Square Kilometre Array (SKA).

Rising costs have forced scientists to cut back plans for the world’s largest radio telescope, known as the Square Kilometre Array (SKA).

We consider a decaying scalar dark matter (DM) with mass $m_\chi$ in the range 10 GeV - 10 TeV and vary the branching ratios of all possible two-body SM final states (excluding and including $\nu\bar{\nu}$) in the range $0\%-100\%$ to derive constraints on the total decay width $\Gamma$ using the data collected by several astrophysical and cosmological observations. We find that, $\Gamma \lesssim 10^{-26} - 10^{-27}\,{\rm s}^{-1}$ (excluding $\nu\bar{\nu}$) and $\Gamma \lesssim 10^{-24} - 10^{-26}\,{\rm s}^{-1}$ (including $\nu\bar{\nu}$) are allowed, depending on the values of $m_\chi$, which are most robust upper limits on $\Gamma$ for a generic decaying scalar DM. We then investigate the prospect of the upcoming Square Kilometre Array (SKA) radio telescope in detecting the DM decay induced radio signals originating inside the dwarf spheroidal (dSph) galaxies. We have classified the DM parameter space, allowed by the existing observations, independently of the branching ratio of each individual two-body SM final state, based on the detectability at the SKA. Excluding the $\nu\bar{\nu}$ decay mode, we find that, throughout the DM mass range considered, $\Gamma \gtrsim 10^{-30}\,{\rm s}^{-1} - 10^{-29}\,{\rm s}^{-1}$ is detectable for all possible branching ratio combinations at the SKA (assuming 100 hours of observation time), with conservative choices for the relevant astrophysical parameters. On the other hand, when arbitrary branching ratios are allowed also for the $\nu\bar{\nu}$ decay mode, DM decays can be probed independently of the branching ratio of each SM final state for $\Gamma \gtrsim 2 \times 10^{-29}\,{\rm s}^{-1}$, provided DM masses are greater than a few hundreds of GeV.

The Square Kilometre Array (SKA), a flagship 21st-century radio astronomy project [1], necessitates a global distributed network of SKA Regional Centres (SRCs) to address its unprecedented data processing, storage, and distribution needs [2,3].The China SKA Regional Centre (cnSRC) is under development as a critical component of the international SRCNet, this system architecture is designed to flexibly support both High-Performance-Computing (HPC) and Kubernetes container orchestration, enable scientific data access for the Chinese and broader international astronomy communities [4].This presentation provides and overview of the cnSRC's current status, cncompassing its computing infrastructure, data processing capabilities, data management and distribution strategies, scientific research priorities, and user support services [3].We introduce the cnSRC's architecture, strategy, and implementation progress, focusing on the deployment of federated computing models, high-speed networking solutions, and scalable data management systems.Furthermore, we discuss the development of the software framework and data pipelines designed to support SKA workflows, including data ingestion, processing, visualization, and user interaction.By aligning with SKA's global SRC architecture and policies, cnSRC aims to provide a robust and efficient platform for enabling SKA science in China and beyond.We also highlight the robust collaborative framework emerging among Asia-Pacific SKA Regional Centres, with a particular focus on the strong partnership between China and Australia in advancing radio astronomy, demonstrating the region's collective commitment.

This study presents the findings of using the Square Kilometre Array (SKA) telescope to measure redshift drift via the H i 21 cm signal, employing semiannual observational intervals within a redshift of around z ∼ 1 with a main goal of directly gauging the Universe’s expansion acceleration rate with mm s−1 precision. The SKA can detect over 1 billion H i 21 cm emissions from individual galaxies to redshift z ∼ 2 and thousands of absorption lines from damped Lyα systems against bright quasars to redshift z ∼ 13 with a sensitivity limit of 100 mJy. By utilizing SKA’s high spectral resolution settings (0.001, 0.002, 0.005, 0.01 Hz) to detect redshift drift, particularly focusing on the 0.001 and 0.002 Hz configuration, one aims to achieve the necessary mm s−1 in precision measurement by the 0.5 yr observation period. The velocity drift rate, crucially determined by the two operational regimes within 0.01–0.21 mm s−1 and 0.031–0.17 mm s−1, exceeds the theoretical accuracy limit of 1.28 mm s−1. The analysis thoroughly restricts cosmological parameters related to dark energy using the Sandage–Loeb (SL) signal from the H i 21 cm emission and absorption lines. It estimates a H 0 of about 70 km s−1 Mpc−1, Ωm near 0.3, and w close to −1, w 0 around −1, and wa approaching −0.1. These results strongly endorse the SL effect as an effective method for confirming cosmic acceleration and exploring the dark sector in real-time cosmology with the SKA.

Current imaging observations of protoplanetary disks using the Atacama Large Millimeter/submillimeter Array (ALMA) primarily focus on the submillimeter wavelength, leaving a gap in effective observational approaches for centimeter-sized dust, which is crucial to the issue of planet formation. The forthcoming Square Kilometre Array (SKA) and ngVLA may rectify this deficiency. In this paper, we employ multifluid hydrodynamic numerical simulations and radiative transfer calculations to investigate the potential of SKA1-Mid, ngVLA, and SKA2 for imaging protoplanetary disks at subcentimeter/centimeter wavelengths. We create mock images with ALMA/SKA/ngVLA at multiwavelengths based on the hydrodynamical simulation output and test different sensitivity and spatial resolutions. We discover that both SKA and ngVLA will serve as excellent supplements to the existing observational range of ALMA, and their high resolution enables them to image substructures in the disk’s inner region (∼5 au from the stellar). Our results indicate that SKA and ngVLA can be utilized for more extended monitoring programs in the centimeter wave band. While in the subcentimeter range, ngVLA possesses the capability to produce high-fidelity images within shorter observation times (∼1 hr on source time) than previous research, holding potential for future survey observations. We also discuss for the first time the potential of SKA2 for observing protoplanetary disks at a 0.7 cm wavelength.

Large scale radio astronomy (RA) activity, brought to focus in South Africa with the Square Kilometre Array (SKA) developments, only began to impact on local engineering teams from around 2004. The country's first demonstrator was ready for evaluation towards the end of 2007. It was at that point that my EMRIN group's engagement on radio frequency interference (RFI) began. After a review of a number of European RA sites, and doing some calculations of required electromagnetic quietness required for viable SKA observations, it became apparent that RFI management would be a major priority for any contemporary large radio research instruments. This talk will discuss components of site development that are now considered essential for any such instruments to be regarded as robust. The presentation will review: 1. Electromagnetic compatibility (EMC) principles illustrated with simple schematic experiments and computational electromagnetics. The pictorial material will emphasise an understanding of current paths, resistive, E and B-field coupling mechanisms and then the use of enclosures, interfaces and cabling structures [1-3]. Some suitable sensors and their calibration will be described [4-6]. 2. Various radio astronomy observatories (RAO's) that have been visited in Europe and South Africa which will be considered in the light of these principles. 3. Experience gained from the South African experimental demonstrator model (XDM), the Karoo Array Telescopes (KAT-7 and MeerKAT) and some Square Kilometre Array (SKA) precursor lower-frequency arrays [7-21]. 4. Requirements for designing robust large radio research instruments where challenges for these large science projects will be posed. The two primary purposes of the presentation will be to: a) promote the viewpoint that site and instrument construction must embrace EMC principles from the start, and b) encourage the interaction of engineers, scientists and astronomers throughout the development process.