More Transients and Pulsars (MeerTRAP) is an ERC-funded project to search for fast radio transients, including pulsars and Fast Radio Bursts (FRBs), using the MeerKAT telescope in South Africa. To that end, we employ the FBFUSE beamformer combined with a real time, single pulse search pipeline that operates commensally with other MeerKAT users. Thus, in over five years of regular observing, we...
The Crab Nebula serves as a unique laboratory for studying the acceleration of electrons and positrons through their non-thermal radiation. In this contribution, I would like to present the first fully self-consistent analysis of the Crab Nebula’s γ-ray emission over five orders of magnitude in energy (from 1 GeV to ∼100 TeV). By combining 11.4 years of data from the Fermi Large Area Telescope...
Excess of gamma rays with a spherical morphology around the Galactic center (GC) at GeV energies observed in the Fermi-LAT data is one of the most intriguing features in the gamma-ray sky as it is consistent with annihilation of dark matter particles. Astrophysical explanations include a population of millisecond pulsars (MSPs). We use machine learning algorithms to search for MSP candidates...
Pulsars are highly magnetised, rapidly rotating neutron stars that emit beams of electromagnetic radiation from their magnetic poles and are remarkable laboratories for testing theories of gravity, studying neutron star interiors, and constraining equations of state. Previous surveys searching for such intriguing objects have provided high-impact science results, and new-generation radio...
The Galactic Centre is a region filled with non-thermal astrophysical phenomena, making it a prime target for cutting-edge research using advanced radio telescopes. Using the capabilities of the MeerKAT S-Band receiver, our research is dedicated to finding pulsars within this complex region.
Pulsars, the highly magnetized, rotating neutron stars, are expected to be abundant in the Galactic...
We present an investigation of the L-band emission from known massive young stellar objects (MYSOs) in the SARAO MeerKAT Galactic Plane Survey to search for non-thermal radio emitters from the sample. A total of 398 massive protostars, identified from the Red MSX Source (RMS) survey, are located within the survey region. Among these, 164 fields that host the protostars are isolated from nearby...
The recent detection of the gamma-ray burst GRB 221009A has garnered significant attention due to its unprecedented brightness and the first-ever detection of very-high energy (VHE, > 10 TeV) gamma rays from a GRB at the redshift of z=0.151. This redshift indicates a distance at which the gamma-ray flux at these energies would typically undergo severe attenuation due to gamma-gamma pair...
The unified model of jetted active galactic nuclei (AGNs) based on intrinsic properties presumes that the blazar subtypes of BL Lacertae objects (BLs) and flat-spectrum radio quasars (FSRQs) are aligned equivalents of Fanaroff–Riley type I (FR I) and Fanaroff–Riley type II (FR II) radio galaxies from where their parent sources are obtained. Using compiled radio, X-ray and γ-ray data of 397...
I present the results of my Master's project to comprehensively search for high-redshift radio galaxies (HzRGs) within 37 fields of the MeerKAT Galaxy Cluster Legacy Survey's first data release. These fields are distinguished by their good dynamic range and comprehensive optical and infrared coverage through the Dark Energy Camera Legacy Survey and the All-sky Wide Infrared Survey Explorer....
Observations of galaxy clusters at low radio frequencies serve as a valuable tool for studying the non-thermal intracluster medium (ICM). Diffuse radio emissions, such as radio halos and relics, assist in probing a cluster’s non-thermal physics and magnetic fields. However, radio observations lack redshift information, rendering it challenging to determine the origin of extended radio...
Namibia, renowned for its pristine night skies and minimal light pollution, has emerged as a significant hub for astronomical research. Hosting the first International Dark Sky Association (IDA) Dark Sky Reserve in Africa, the NamibRand Nature Reserve, Namibia boasts ideal conditions for astronomical observations. This work delves into measurements of night-sky brightness proximal to the...
A significant fraction of the highest energy gamma-ray astrophysical sources observed are associated with Pulsar Wind Nebulae (PWNe). Given recent observations, the postulated, but unverified, hadronic component from PWNe requires renewed attention in the long search for PeVatrons. We estimate possible ranges for the average pulsar pair production multiplicity on 31 sources in the Australia...
Galaxies exhibit a wide variety of observable properties. The environment in which a galaxy resides is known to significantly impact its characteristics. A galaxy's cold gas component (usually a disk for late-type systems) is particularly sensitive to environmental conditions. Neutral atomic hydrogen (HI) as we know it, makes up the large majority of a galaxy's gas content.
Galaxies are...
We present an investigation of the properties of radio relics (RRs), one type of diffuse emission located at the outskirts of some Galaxy Clusters (GCs), and a search for information about the origin of non-thermal processes taking place in the cluster atmospheres. We adopt a new approach to constrain models for the origin of RRs according to the following steps: i) Instead of working on a...
The chemical abundance of active galaxies, which host active galactic nuclei (AGN) at their centre, remains poorly studied, most often due to the difficulty of removing the effect of AGN in metallicity measurements. In particular, the chemical abundance of active galaxies in different environments, including clusters and groups of galaxies, is still unknown. In this work, we use a novel HCm...
The MeerKAT Exploration of Relics, Giant Halos, and Extragalactic Radio Sources (MERGHERS) survey is targeting a homogeneously selected sample of SZ-detected galaxy clusters with the aim of probing the cosmic and mass evolution of diffuse cluster radio emission. Almost all statistical cluster samples studied for diffuse radio emission are restricted to low-redshift, high-mass clusters due to...
cores, provides valuable insights into supermassive black holes, galaxy evolution, and cosmic environments. The Africa Millimetre Telescope (AMT) that will be constructed in the Khomas Highlands in Namibia will be designed to add to the Event Horizon Telescope (EHT) network. With the AMT, the EHT will be able to produce colour movies of black holes, allowing us to better determine their...
We present the second data release of the MeerKAT Absorption Line Survey (MALS), consisting of wideband continuum catalogues of 391 pointings observed by MALS at L band. The full wideband catalogue covers 4344 deg$^2$ of sky with a depth down to $10\ \mu \mathrm{Jy\ beam}^{-1}$, and contains 971,980 sources. With its balance between survey depth and sky coverage, MALS DR2 covers five orders of...
From observations, we see non-thermal radio emission with emissivity ranging from 1 to 3, extended over a large region (∼ megaparsec) in galaxy clusters, which contain largely collisionless plasma. To explain this, the electrons should be energized or accelerated. One explanation is that the energy released during a merger event could be channeled to accelerate electrons through turbulence or...
Studying the radio spectral energy distribution (SED) of distant galaxies is essential for understanding their assembly and evolution over cosmic time. We present rest-frame mid-radio ($\simeq 1-16$\, GHz) SEDs of a sample of starburst galaxies at 1.5 < z < 4.5 in the COSMOS field as part of the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) project. MeerKAT...
