Australia Telescope National Facility

ATCA Science Day, Australia Telescope User Committee Meeting and Postgraduate Student Symposium 8-11 April 2025
2025-04-08 11:00 - 2025-04-11 17:00 (Australia/Sydney) | Marsfield Lecture Theatre, 26 Pembroke Road, Marsfield, NSW, 2122, Australia
Overview

The ATCA Science Day, ATUC Open Session and Postgraduate Student Symposium will be held in Marsfield (Sydney), NSW from 8-11 April 2025. Online attendees will be able to join via Teams.

On 8 April there will be an ATCA Science Day. This will be followed by the ATUC Open Session on 9 April which consists of updates and discussions on the various aspects of ATNF facilities. All are welcome to register to attend the Open Session, using this registration form.

General registration for ATUC will close at 17:00 AWST on 28 March 2025.

On 11 April there will be a Postgraduate Student Symposium. Registration information for the Postgraduate Student Symposium will be sent out shortly.

An agenda, with details for hybrid participation, will be made available to registered attendees closer to the event.

If you, as a user (or potential user) of the ATNF, are aware of any issues that need to be raised at the next ATUC meeting, or would like to offer feedback on ATNF activities and facilities, please contact any member of ATUC over the next few weeks.

Information on ATUC and how to contact its members can be found on the ATUC webpage.

For questions about this form or ATUC in general, please contact Vanessa Moss.

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S&A Colloquium: Michael Kramer (MPIfR, Bonn)
2025-04-16 15:00 - 16:00 | NSW
Exploring Unknown Territory

Radio astronomy is an excellent tool for studying fundamental physics and to probe our edge of understanding. It allows to study compact objects, black holes at all mass scales and neutron stars, gravitational waves, the equation of state of superdense matter, magnetism, cosmology, to name but a few. This talk will give an overview of the ongoing efforts at the MPIfR in Bonn in terms of scientific projects, instrumentation and strategic considerations, supported by the presentation of recent results.
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Colearnium: Jennifer Zhu
2025-04-17 12:00 - 12:30 | NSW
How to pronounce Kangiqsualujjuak ᑲᖏᖅᓱᐊᓗᔾᔪᐊᖅ

This week Jennifer Zhu will present on “How to pronounce Kangiqsualujjuak ᑲᖏᖅᓱᐊᓗᔾᔪᐊᖅ”.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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S&A Colloquium: Erik Osinga (Dunlap Institute, University of Toronto)
2025-04-30 15:00 - 16:00 | CSIRO – Kensington, Australian Resources Research Centre (ARRC), 26 Dick Perry Ave, Kensington, WA, 6101, Australia
Galaxy clusters as the Universe’s largest particle accelerators

Abstract

Mergers of galaxy clusters represent the most energetic events since the Big Bang, releasing energies up to 1064 ergs over Gyr timescales. This energy is dissipated through shocks and turbulence in the intra-cluster medium, transforming clusters into the Universe’s largest laboratories for studying cosmic ray acceleration and magnetic field amplification. However, our understanding has largely been limited to massive and nearby clusters due to observational constraints. In this talk, I will show how observations at the longest wavelengths observable from the ground are revealing new insights into both turbulence and magnetic field amplification. Additionally, I will discuss how advances in radio polarimetry and new surveys such as POSSUM are revealing the first detailed magnetic field structures within individual clusters.
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Colearnium: Ivy Wong (CSIRO)
2025-05-01 12:00 - 12:30 | NSW
AI/ML work carried out by ATNF Science staff

This week Ivy Wong will present on “AI/ML work carried out by ATNF Science staff”.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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CSIRO S&A Colloquium: Prof. Anna Scaife (University of Manchester)
2025-05-05 14:00 - 15:00 | NSW
Foundation models for astrophysics

Abstract

Pre-trained representations from large volumes of unlabelled astronomical survey data are rapidly emerging as a key AI technology in astrophysics. I will review some of the recent applications of these models, including within the software pipeline for the ESA Euclid mission, highlight their advantages – and some potential issues. I will describe our recent work looking at recovering calibrated uncertainties from such models and conclude with a future outlook.
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Colearnium: Shane Hengst (CSIRO)
2025-05-08 12:00 - 12:30 | NSW
Follow the dust: evolution of planetary systems

This week Shane Hengst will present on “Follow the dust: evolution of planetary systems”.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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Colearnium: Jishnu Thekkeppattu (Curtin)
2025-05-15 12:00 - 12:30 | NSW
Monitoring ionospheric scintillation using low-cost software defined radios

This week Jishnu Thekkeppattu will present on “Monitoring ionospheric scintillation using low-cost software defined radios”.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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Bolton Symposium 2025
2025-05-20 09:30 - 2025-05-21 13:00 | CSIRO – Kensington, Australian Resources Research Centre (ARRC), 26 Dick Perry Ave, Kensington, WA, 6101, Australia
About the Symposium

The Bolton Symposium, named after the first director of Murriyang, our Parkes radio telescope, John Gatenby Bolton (1922-1993), provides a forum for early-career research (ECR) staff within the Australia Telescope National Facility to showcase their excellent science, find out what colleagues are up to, and to develop and strengthen collaborations.

The Bolton Symposium 2025 will be held on May 20-21, 2025. The symposium will be held in-person at the CSIRO Kensington site, and via Teams for remote/hybrid attendees.

The first day of the symposium will be an open day with science talks from ATNF ECRs, and the second day will hold a closed session dedicated to practical discussions for ECR career development and getting the most out of their time with CSIRO.

Agenda

Science day: 20 May (09:30 – 15:00 AWST / 11:30 – 17:00 AEST)

Time (AWST)TitleSlidesPresenterSession chairSession 1: VLBI Science09:30-09:40Welcome09:40-09:55Deep learning Very-long Baseline Interferometric Imaging with Closure InvariantspdfSamuel LaiAndrew Zic09:55-10:10Advancing SETI with VLBIDongjin Kim10:10-10:25VLBI astrometry with OH masers in the Milky WayJayender Kumar10:25-10:40ASKAP VLBIpdfKelly Gourdji10:40-11:10Morning TeaSession 2: Pulsars, time-domain, and low-frequency techniques11:10-11:25Unlocking the hidden potential of pulsar astronomyDilpreet KaurBarnali Das11:25-11:40Quantum meets pulsarspdfWenhua Ling11:40-11:55A visibility-based periodicity search techniquepdfAndrew Zic11:55-12:10Dynamic spectroscopy of polarised radio transientspdfJosh Preston-Pritchard12:10-12:25Precision Low-Frequency Radio Sky Brightness MeasurementpdfLuke McKay12:25-12:40All m-mode transit interferometry with the EDA2 and the MWAJaiden Cook12:40-13:30LunchSession 3: Radio surveys and machine learning13:30-13:45Radio surveys from 300 to 1655 MHzpdfStefan DuchesneKelly Gourdji13:45-14:00What to do with Big Data in Astronomy?pdfNikhel Gupta14:00-14:15Unveiling the Southern Magnetised Sky with ASKAPpdfAlec Thomson14:15-14:30From Cube to Catalogue: End-to-End Source Finding with a 3D Foundation ModelpdfLi Wang14:30-14:45Magnetic hot stars in ASKAP surveyspdfBarnali Das14:45-15:00John Bolton and his impact on astronomypdfRon Ekers15:00Close/afternoon tea

Postdoc career development (ATNF postdocs only): 21 May (09:30 – 13:00 AWST / 11:30 – 15:00 AEST)

Time (AWST)TitlePresenter09:30-10:00The ATNF and YouGeorge Hobbs (ATNF)10:00-10:15ATNF Computing InfrastructureShaun Amy (ATNF)10:15-10:35CSIRO High Performance ComputingDaniel Collins (CSIRO IM&T)10:35-11:05Preparing SKA-Low for Science: Commissioning a Next-Generation Low-Frequency ArrayShivani Bhandari (SKAO)11:05-11:30Morning Tea11:30-12:15Career ProgressionNick Carter, Jimi Green, Jane Kaczmarek, Nipanjana Patra12:15-12:45How technology can enhance your scienceKeith Bannister (ATNF)12:45Lunch/closeAfternoonCollaboration time + SKAO Tour

Venue

Venue information

The symposium will be held in the ARRC Auditorium. For visitor access, please sign in at Reception. The Auditorium is immediately on the right after the main entry.

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Code of Conduct

By attending this event, you agree to comply with the ATNF Events Code of Conduct:https://www.atnf.csiro.au/code-of-conduct/

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Colearnium: George Hobbs (CSIRO)
2025-05-22 12:00 - 12:30 | NSW
An introduction to Blender

This week George Hobbs will present on “An introduction to Blender“.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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CSIRO S&A Colloquium: Connor Bottrell (UWA)
2025-05-28 13:00 - 14:00 | CSIRO – Kensington, Australian Resources Research Centre (ARRC), 26 Dick Perry Ave, Kensington, WA, 6101, Australia
Mini mergers with major consequences in a cold dark matter universe

Abstract

The gravitational forces measured beyond the Solar System tell us that 85% of the matter in the Universe is invisible. But despite its abundance, dark matter has so-far avoided direct detection by laboratory experiments on Earth. As a result, particle physics theory has flourished to develop dark matter candidates that span a wide range of masses and phenomenologies. In this talk, I will discuss some consequences of dark matter physics on galaxies including the predicted abundances of low-mass dark matter halos. In particular, I will show that “mini” collisions with low-mass halos have an inconspicuously important role in driving diversity amongst large star-forming galaxies in cosmological simulations. These collisions are ubiquitous in the Cold Dark Matter cosmogony, but suppressed by warmer, lighter dark matter particles.
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Colearnium: George Heald (CSIRO)
2025-05-29 12:00 - 12:30 | NSW
The making of the first SKA-Low image

This week George Heald will present on “The making of the first SKA-Low image“.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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Colearnium: Leticia Brown (Casey)
2025-06-12 12:00 - 12:30 | NSW
LinkedIn Masterclass

This week Leticia Brown will present on “LinkedIn Masterclass“.

Leticia has over 9 years of experience working in communications and social media across non-for profit and government sectors, including working at South Africa’s oldest science centre Sci-Enza under DFAT’s Australian Volunteers program.

She is currently the Team Leader of Communications and Brand at one of Victoria’s largest and fastest growing councils – City of Casey. Within this role, she leads their LinkedIn strategy as well as training and empowering staff in effective LinkedIn engagement: significantly building the organisation’s presence on the platform through the power of people stories.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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S&A Colloquium: Ajay Kumar (NCRA, Pune)
2025-06-18 15:00 - 16:00 | NSW
Probing Fast Radio Bursts Using Deep Learning and GMRT

Fast Radio bursts are bright dispersed radio pulses of cosmological origin. Currently, several hundred of them are known and published. The population of FRBs are classified as one-off events and repeaters. A small fraction of FRBs are active repeaters, which can be studied in great detail to gain insights into their origins and emission mechanism. The discovery rate of FRBs is already a few per day and is expected to increase rapidly with new surveys coming online. The growing number of events necessitates prioritized follow-up due to limited multi-wavelength resources.

I will describe Frabjous, a deep learning framework for an automated morphology classifier, with an aim towards enabling the rapid follow-up of anomalous and intriguing FRBs and a comprehensive statistical analysis of FRB morphologies. I will then discuss the results obtained from the application of Frabjous on simulated and first CHIME/FRB catalog and the potential for more accurate and reliable classification.

I will also present the results from recent observational campaigns of several active repeaters, including FRB 20220912A, FRB 20240114A and FRB 20240619D using uGMRT. Furthermore, I will describe their burst properties, energy distributions, host environments, and temporal evolution of burst rates at lower radio frequencies. Finally, I will discuss the implications of our results in the context of proposed progenitors models and emission mechanisms for repeating FRBs.
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Colearnium: Phil Collins (CSIRO)
2025-06-26 12:00 - 12:30 | NSW
HSE Risk Management

This week Phil Collins will present on “HSE Risk Management“.

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​​Lunch and learn – 26th June (Topic – HSE Risk Management)

​ Hello all,

​One of the key messages from the DNFC Sector Research Units staff in the FY25 HSE Annual Review was the need for greater awareness and understanding of HSE procedures.

​To support this, the HSE Team across CSIRO will be running bi-monthly HSE Awareness Sessions, with each Research Unit facilitating their own. These sessions are optional and open to all Space and Astronomy staff and support functions.

​Each session will include:

​An overview of a specific HSE procedure

​An open discussion

​An opportunity to ask questions

​To get the most value from these sessions, please read the relevant procedure beforehand. HSE Risk Management Procedure – MyCSIRO

​Where applicable, the sessions will align with the HSE Grassroots campaign topic.

​We look forward to your participation!

​Any questions please contact Phil Collins (HSE Manager – S&A)

…………………………………………………

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

Kind regards,

Samuel (On behalf of the co-learnium organisers)

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Colearnium: Elizabeth Mahony (CSIRO)
2025-07-03 12:00 - 12:30 | NSW
Using lotteries to allocate resources (such as telescope time)

This week Elizabeth Mahony will present on “Using lotteries to allocate resources (such as telescope time)“.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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S&A Colloquium: Alex Cooper (University of Oxford)
2025-07-23 15:00 - 16:00 | NSW
Magnetar Mysteries: Tales of Two Radio Transients

Magnetars, highly magnetized neutron stars, are responsible for the most energetic transient events observed in the Milky Way. Their extreme magnetic environments enable exotic quantum processes, such as spontaneous photon splitting and photo-magnetic electron-positron pair production, providing unique avenues for testing fundamental physics under conditions not reproducible elsewhere in the universe.

In this talk, I will examine two distinct classes of radio transients thought to be associated with magnetars: the recently discovered galactic Long Period Transients, and extragalactic Fast Radio Bursts. I will present the observational evidence supporting the magnetar hypothesis, discuss current theoretical models explaining how magnetars might produce these phenomena, and outline the implications for our broader understanding of neutron stars and transient astronomy. I will conclude with the prospects for future research and discoveries in this rapidly evolving area of astrophysics.

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Colearnium: Jimi Green (CSIRO)
2025-07-24 12:00 - 12:30 | NSW
Jimi’s Office Contents

This week Jimi Green will present on “Jimi’s Office Contents“.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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S&A Colloquium: Erin Hestir (University of California, Merced)
2025-07-28 15:00 - 16:00 | NSW
From Genes to Pixels: Advancing Invasion Science and Restoration through Integrated Observations

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S&A Colloquium: Erin Hestir (University of California, Merced)
2025-07-30 15:00 - 16:00 | NSW
Space-Based Tools for California’s Water Quality Challenges: Linking Satellites to Solutions

More than 3 billion people around the world lack access to reliable information about the quality of the water they drink. As wildfires, drought, and land degradation intensify, our water systems face growing pressure—not just from scarcity, but from worsening quality. Communities, ecosystems, and economies increasingly depend on timely, science-based data to manage risks and build resilience.

In this seminar, I will explore how satellite-based Earth observations are transforming the way we monitor, understand, and protect water quality. Drawing on case studies from across California, I will demonstrate how spaceborne data are being used to detect harmful algal blooms and emerging contaminant, assess the impacts of megafires and floods, support habitat conservation, and inform public health and resource management decisions. These tools are playing a growing role in bridging science, technology, and policy—offering decision-makers actionable insights to address both immediate challenges and long-term sustainability goals.
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Colearnium: Nikhel Gupta (CSIRO)
2025-07-31 12:00 - 12:30 | NSW
Searching the Radio Sky with AI

This week Nikhel Gupta will present on “Searching the Radio Sky with AI“.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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CSIRO S&A Colloquium: Mattias Lazda (University of Toronto)
2025-08-05 13:00 - 14:00 | CSIRO – Kensington, Australian Resources Research Centre (ARRC), 26 Dick Perry Ave, Kensington, WA, 6101, Australia
The CHIME/FRB Outriggers: Project Overview and Commissioning Results

Abstract

The CHIME/FRB Outriggers are a network of radio telescopes spanning continental North-America. Designed specifically for localizing fast radio bursts (FRBs) to <50 mas precision using very-long-baseline-interferometry, the Outriggers will enable the precise localization of hundreds of non-repeating FRBs, per year, once fully operational. With the recent construction of the third and final outrigger now complete, the Outriggers have officially unlocked the capability of precisely localizing non-repeating FRBs. In this talk, I will provide an overview of the CHIME/FRB Outriggers project and a summary of the first stage of commissioning. By validating astrometric performance using a sample of known sources (e.g. pulsars and continuum sources), we show that the Outriggers can achieve a localization precision of 50 mas x 100 mas for a typical FRB event. I will discuss on-going efforts and upcoming plans to improve this ability to localize FRBs to the eventual goal of 50 mas x 50 mas precision for the majority of events detected by the CHIME/FRB Outriggers. I will close by highlighting the number of early science results that have been enabled by the Outriggers.
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S&A Colloquium: Sanne Bloot (ASTRON / Kapteyn Astronomical Institute)
2025-08-06 15:00 - 16:00 | NSW
From exoplanets to long-period transients: Coherent radio emission from binary systems

Abstract

Many binary systems produce coherent radio bursts, from the Jupiter-Io system to star-planet interactions to systems as exotic as long-period transients. While these bursts can look very different in terms of timescales and luminosity, they all have something in common: an interaction with a companion. In this talk, I will discuss the radio emission from stars, brown dwarfs, and long-period transients. I will cover observing strategies for these different types of transients as well as physical explanations for their emission, showing that the fields of slow and fast transients overlap in more than just the name.
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Colearnium: Max Charles (USyd)
2025-08-07 12:00 - 12:30 | NSW
AMIGO and the James Webb Interferometer

This week Max Charles will present on “AMIGO and the James Webb Interferometer“.

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

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Samuel (On behalf of the co-learnium organisers)

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S&A Colloquium: Kshitij Bane (NCRA, Pune)
2025-08-13 15:00 - 16:00 | NSW
Under the SPOTLIGHT: Hunting Fast Transients in Real Time with the uGMRT

Abstract:The detection of Fast Radio Bursts (FRBs) has grown exponentially in recent years, but real-time localisation with high precision remains one of the key challenges in the field. SPOTLIGHT is a next-generation system developed at the upgraded Giant Metrewave Radio Telescope (uGMRT) to tackle this challenge. Operating commensally with regular uGMRT observations, SPOTLIGHT employs a high-performance, multi-node GPU cluster to handle petabyte-scale data processing in real time, steering 2000 post-correlation beams at sub-millisecond resolution.

Powered by an AI-driven transient detection pipeline, SPOTLIGHT not only captures FRBs in real time but also triggers arcsecond-level imaging and raw voltage dumps for high-resolution studies across the 300–1460 MHz band. With its exceptional sensitivity, SPOTLIGHT is expected to detect and localise hundreds of FRBs, offering exciting prospects for understanding their origins.

In this talk, I will present an overview of the SPOTLIGHT project, its architecture, performance, recent tests, and the scientific opportunities it unlocks.

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Colearnium: Phil Collins (CSIRO)
2025-08-14 12:00 - 12:30 | NSW
HSE: Chemicals and Gases

This week Phil Collins will present on “HSE: Chemicals and Gases“.

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​​Lunch and learn – 14th Aug (Topic – HSE)

​ Hello all,

As part of the HSE Plan 25-27 and our values of ‘Further Together’ the CSIRO HSE ‘Grassroots Campaign’ has a focus on HSE Procedure Awareness.

The HSE Team is working together to develop the information for these sessions which will be delivered by the HSE Manager from each RU. This invitation is open to all Space and Astronomy.

The sessions themselves will be an overview of the procedure, followed by discussion and opportunity for questions.

To get the most from attending the session read the procedure prior to attending – Hazardous Chemicals and Gases Procedure – MyCSIRO

Subject Matter Experts will be in the sessions or provide content (where relevant and available) to add specific insight into the discussions.

​Any questions please contact Phil Collins (HSE Manager – S&A)

…………………………………………………

Please let me know if you’re willing to present at a future co-learnium or have requests for specific talks, thanks!

Kind regards,

Samuel (On behalf of the co-learnium organisers)

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S&A Colloquium: Piyush Mehta (CISER / West Virginia University)
2025-08-14 14:00 - 15:00 | NSW
Next-Gen Tools and Techniques for Space Situational Awareness and Space Traffic Management

Abstract:Space debris remains a persistent threat to assets and humans in space. The proliferation of low Earth orbit (LEO) with replenishable small satellite constellations driven by commercial interests has further stressed Space Situational Awareness (SSA) and put focus onSpace Traffic Management (STM). While the trackable debris catalog has grown significantly over the last decade, lethal non-trackable (LNT) debris smaller than the order of centimeters in size remains a challenge as they fall below the detection and tracking capability of most ground-based sensors. In addition to catalog maintenance under SSA, STM has put focus on enhanced and concerted space operations that includes conjunction assessment and collision avoidance.

The US Space Policy Directive-3, National STM Policy has emphasized the necessity “to make significant contributions to establish a quality threshold for actionable collision avoidance warning to minimize false alarms”. Accurate calculation of Probability of Collision (PoC) for confident decision-making requires realistic covariance information since maneuvers are expensive (personnel cost, science data or commercial service outage, fuel costs). This talk will cover the work developing tools and algorithms targeted at addressing the challenge of LNT debris and enhancing LEO operations, critical for a safe and sustainable space economy and environment.

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S&A Colloquium: Rowina Nathan (Monash University)
2025-08-20 15:00 - 16:00 | NSW
Understanding the gravitational wave background: pulsar timing arrays and skymapping

Abstract:In June 2023, members of the International Pulsar Timing Array (IPTA) released coordinated evidence for the gravitational wave background. In this seminar, I will explain how pulsar timing arrays measure the gravitational wave background and discuss the latest results from various arrays.The MeerKAT radio telescope, one of the most sensitive in the world, has detected similar evidence after just 4.5 years of data collection through the MeerKAT Pulsar Timing Array. Thanks to its exceptional sensitivity and the new methods we have developed, we have produced the most accurate maps of the gravitational-wave background to date. I will discuss our advances in skymapping methods and results. Mapping is crucial for understanding the origin of this background, as an anisotropic background suggests supermassive black-hole binaries as the source. Notably, we identify a hotspot in the 7 nHz map with a p-value of 0.015.

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S&A Colloquium: Rick Perley (NRAO)
2025-08-26 15:00 - 16:00 | NSW
Precision Meter-wavelength Polarimetry with the Jansky Very Large Array

Abstract:Accurate polarimetry at meter-wavelengths requires correction of the ionospheric Faraday rotation measure (IFRM) with an accuracy better than 0.15 rad/m2. In this talk I will show the results of testing of both global and regional estimates of the IFRM generated from GNSS timing data. These tests used extensive polarimetric observations by the VLA and MeerKAT of the Moon, the only source of polarized emission with an a priori known electric vector position angle distribution.

We find that all global estimates made from maps of the vertical total electron content (VTEC) by various agencies overestimate the IFRM for VLA observations by 0.3 to 1.0 rad/m2, while a regional model, utilizing GNSS data from stations near the VLA is much better, with errors of typically 0.15 rad/m2. This is sufficiently accurate for VLA observations at 300 MHz, but not for lower frequencies.

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S&A Colloquium: Arpan Pal (NCRA, Pune)
2025-08-27 15:00 - 16:00 | NSW
When Clusters Collide and Telescopes Misbehave: My Life as a Radio Astronomer

Abstract:When galaxy clusters collide at thousands of kilometers per second, they create cosmic particle accelerators spanning millions of light years, driving shocks that accelerate particles and amplify magnetic fields to produce diffuse radio emissions revealing the invisible architecture of these extreme environments. I’ll present low-frequency polarization observations of merging galaxy clusters using the upgraded Giant Metrewave Radio Telescope (uGMRT), supported by X-ray and high-frequency radio data from VLA and MeerKAT.

Surprisingly, we found that low-frequency polarization does not follow high-frequency predictions, with depolarization inconsistent with single-component magnetic field models. We present the first linear polarization detection below 1 GHz requiring multicomponent magnetic field distribution, challenging conventional shock compression models in radio relics. However, reliable polarization extraction proved challenging due to mysterious time-variable instrumental effects initially appearing astrophysical. Extensive systematic investigation of the telescope’s signal chain – involving months of debugging, testing individual components from feeds to correlators, and eliminating potential sources one by one – eventually identified an unexpected instrumental culprit responsible for these anomalous signals.

This detective work highlights how instrumental systematics can masquerade as cosmic phenomena and I will walk through this technical adventure. To handle the massive data volumes from modern radio surveys, we developed “Charizard,” a fast radio imaging pipeline using aggressive parallelization strategies that processes terabytes of interferometric data orders of magnitude faster than traditional approaches. This speed enables more iterative analysis, better systematics characterization, and the ability to tackle larger statistical samples of merger systems.

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