Research Specialisation: Solar Astrophysics, Solar quiet field, and data analysis Technique.

Title of the project: Magnetic Energy Balance in the Quiet Sun

Abstract:

Small-scale magnetic fields in the quiet solar photosphere are believed to store and transfer a large amount of energy to the outer photospheric part. A mechanism responsible for the storage of energy in the solar photosphere and its transport to the atmospheric layer has importance to solar active regions and quiet Sun, where space weather phenomena originate. Therefore, it is fundamental to study the properties of the deriving quantities (e.g. magnetic energy density) of the quiet Sun. In this project, the student will use magnetograms acquired from a space experiment to evaluate the vertical magnetic field and the Fast Local Correlation Tracking technique ( FLCT) to compute the plasma horizontal velocity field.

Requirements: The student should be familiarized with computer software and programming language. A background in theoretical physics and image analysis.

Contact Person: Negessa T. Shukure (PhD)
Addis Ababa University
College of Natural Sciences
Department of physics
Email: nagessa2006@gmail.com
Telephone: (+251) 910145236
P.O. Box 33679
Addis Ababa,
Ethiopia

Research Specialisation: Solar Astrophysics, Solar Variability, and data analysis Technique.

Title: The Solar Surface Magnetic Flux Density and Solar UV Irradiance Variability

Abstract:

Solar surface magnetic flux (SSMF) is assumed to be the main deriver of solar UV variability in the longer timescale. Therefore, understanding its variability and influence on UV irradiance is used to introduce the new index that uses the SSMF as an input. The main purpose of this project is to identify a magnetic flux density (MFD) interval that is responsible for UV variability and the UV dependency on MFD. In this project, a student will use data from the Solar Dynamic Observatory (SDO)/Helioseismic Magnetic Imager (HMI) instrument to develop the time series of SSMF and UV proxy models for further analysis. The new index introduced here will be helpful in solar and solar-terrestrial studies.

Requirements: The student should be familiarized with computer software and programming language. A background in physics and image analysis.

Contact Person: Negessa T. Shukure (PhD)
Addis Ababa University
College of Natural Sciences
Department of physics
Email: nagessa2006@gmail.com
Telephone: (+251) 910145236
P.O. Box 33679
Addis Ababa,
Ethiopia

Research Specialisation: Space Physics

Title: Thermosphere-Ionosphere coupling

Abstract:

The vertical gradients of the pressure in the thermosphere results winds that move the electrically conducting fluid through the geomagnetic fields, that further generates a dynamo effect. Electric fields and currents play an important role in the dynamics of the upper atmosphere for both neutral and partially ionized plasma components. The vertical electric field is generated by the low-latitude wind, the electrons are drift to wards the east while protons are drift towards the west which produces an east-west electric currents in the same direction as the wind, which reduce the ion drag and result in strong zonal winds. This project will exploit ionospheric dynamo models to calculate, neutral wind parameters, electric conductivities, and other space- and ground-based observatories, together with theoretical modeling, to gain a better understanding of the electrodynamics of our near-Earth environment. The main purpose of the research include: study the variability of the ionosphere, how ionosphere and thermosphere are coupling, and what mechanisms govern the structure and dynamics of the ionosphere irregularities over equatorial ionosphere in response to the thermosphre; how neutral dynamics, electric conductivity, electric field and electric currents are mutually coupled.

Requirements: Computational skills in python/Matla is advantageous A background in Astrophysical object data analysis will be a plus.

Contact Person: Dr. Ephrem Tesfaye,
Telephone: (+251) 913-350-026
Email: :ephrem.tesfaye@aau.edu.et
Addis Ababa University
College of Natural Sciences
Department of Physics
Addis Ababa,
Ethiopia

Research Specialisation: Space Physics

Title: Magnetosphere-Ionosphere coupling

Abstract:

The research project focus on research the Ionosphere and magnetosphere coupling, using observational data from both ground and spacecraft data. The solar wind disturbance on the magnetosphere results in many complex processes, it controls the shape and size of the magnetosphere (MS), it damps energy into MS, and it enhances the global magnetospheric current system. The magnetic reconnection between the solar wind and terrestrial magnetic fields at the magnetopause and at the magnetotail are the key regions for transfer of mass, momentum and energy into the magnetosphere-ionosphere that results a process to transport plasma materials into the pole and equator that enhance Birkeland and equatorial current system respectively. The dynamics can be thought of as driven by electric currents generated at the magnetopause and magnetotail further diverted into the ionosphere and inner MS, forming current loops that transmit stress from the solar wind into the magnetosphereionosphere. Understanding the mechanisms of ionosphere irregularities over geomagnetic equator in response to solar and magnetospheric drivers are still an open issues. We seek qualified applicants, strong in observational big data analysis or theoretical plasma (optional) but computational skills in python/Matlab are required.

Computational skills in python/Matla is advantageous

Host Contact: Dr. Ephrem Tesfaye
Telephone: (+251) 9913-350-026
Email: :ephrem.tesfaye@aau.edu.et
Addis Ababa University
College of Natural Sciences
Department of Physics
Addis Ababa,
Ethiopia

MSc Research Project

Field: Astrobiology and Planetary Geology

The astrobiological potential of Precambrian stromatolites from South Africa and Botswana.

Stromatolites are amongst the earliest evidences for microbial life on our planet. They developed and thrived in a geological period when environmental conditions on earth might have been similar to those on Mars during the Noachian. Precambrian stromatolites can therefore be custodian of precious information for the study of Mars habitability. Moreover, analysis of ancient microbialites on earth can inform us on the potential and limits of analytical techniques in our quest to explore exobiological evidences.

In this project the student will collect, prepare and analyse samples of stromatolitic dolostone and limestones from the lower Transvaal Supergroup of South Africa and Botswana. The samples will be dated in order to provide better constraints to their age of formation and stratigraphic positon. These stromatolites will then be investigating for presence of potentially biogenic minerals and dispersed organic matter (OM) using Raman spectroscopy and for the presence of microbial micromorphologies using a scanning electrons microscope (SEM). The environmental conditions at time of formation of these stromatolites are crucial to establish a parallelism with Noachian Mars. The student will therefore perform a number of geochemical analyses aimed at the study of the fractionation of traditional (C and O) and non-traditional (S, Ca, Mg) isotopes during formation of the microbial carbonates.

Supervisor: Assoc. Prof. Fulvio Franchi
franchif@biust.ac.bw
Earth and Environmental Science Department,
Botswana International University of Science and Technology (BIUST)
Botswana
Co-Supervisor: Prof Robert Bolhar
robert.bolhar@wits.ac.za
School of Geosciences
University of the Witwatersrand

Research Specialisation: Astrophysics

Title: A merger – AGN connection?

Abstract

Active galactic nuclei (AGNs) are accreting supermassive black holes, lying in the center of most (if not all) massive galaxies. However, it is found that driving fuel to the AGN is actually difficult (the angular momentum transfer needed is very large) and it is generally argued that violent relaxation is needed, in the guise of mergers and interactions. There should therefore be a connection between AGN activity and morphological disturbance, or the presence of close companions, but this is not well supported by observations.

We have observed a small sample of interacting galaxy close pairs and merger remnants from the MGC survey, using XMM and the Optical Monitor telescope, at all X_ray bandpasses and the 2300 Å filter in the OM. We wish to compare optical (from SDSS and PanStarrs) and UV morphologies (to identify regions of star formation) and measure the X-ray flux, seeing if it also correlates with star formation regions within each galaxy.

Supervisor: Prof Roberto De Propis
deproprisr@biust.ac.bw
Department of physics and Astronomy
Botswana International University of Science and Technology (BIUST)
Private Mail Bag 16, Palapye
BOTSWANA

Research Specialisation: Astrophysics

Title: Determination Of Stellar Masses In M37 Variable Stars

Abstract:

Most stars are found in binary systems accounting for up to 50%. Some stars are in triple or even higher-multiple systems. This project investigates the stellar masses in M37 variable stars by using a combination of observation and catalogue data from J/ApJ/675/1254/m37var. The Las Cumbres 40cm system of remote telescopes will be used to remotely observe the variable stars.

Contact Person: Prospery Simpemba
pcs200800@gmail.com
Copperbelt University
Department of Physics
School of Mathematics and Natural Sciences
P.O Box 21692
Kitwe, Zambia

Phone: +260 21 2290945
Mobile: +260977704168 (WhatsApp)

Research Specialisation: Astrophysics

Title: Resolving Prestellar Molecular Clumps In External Galaxies

Abstract

The goal of this proposal is to analyse data from ALMA telescope and map prestellar molecular clumps within nearby galaxies to an unprecedented precision in order to compare them against equivalent clumps in our own Galaxy mapped by the Hi-Gal Survey. External galaxies offers an opportunity to look at these structures at different metallicity and the mass spectrum of its molecular clouds. This project seeks to examine these differences on a scale only systematically mapped in our own Galaxy before. The work will use the proved molecular gas mass tracers of CO(2-1), 13(2-1) and C18O(2-1) lines. This project will allow us to examine how external galaxies differences are effecting star formation on an entirely new size scale.

The student is expected to have some good command in Python programming language. A background in Astrophysics and Physics.

Contact Person: Dr. Saul Paul Phiri
saulphiri@gmail.com
Copperbelt University
Department of Physics
School of Mathematics and Natural Sciences
P.O Box 21692
Kitwe, Zambia

Research Specialization:

Title: Constraining the equation-of-state of neutron stars using astrophysical observables

Abstract

Neutron stars are the densest objects in the universe outside black holes. The envisaged properties of matter inside them are well-thought-out with equation-of-state (EoS). Typically, equations-of-state as a theoretical perception are engulfed with enormous uncertainties to the extent that the structures of neutron stars are equation-of-state dependent.

Meanwhile, neutron stars are seen as natural laboratories for understanding the behavior of matter at extreme densities not attainable in our terrestrial laboratories. As such, we rely on astrophysical observations of neutron stars for such indispensable laboratories. Transient astrophysical observables such as core-collapse supernovae, kilonovae, gamma-ray bursts, and gravitational waves from neutron star mergers offer a distinctive examination of the dense-matter EoS. As such, these observables serve as a tool in constraining the dense-matter equations of state. In the realm of low densities, results from laboratory experiments have placed a constraint on the theoretically inferred dense-matter equations. However, such a constraint could not be extrapolated to high densities attainable in neutron star interiors. This shortcoming has moved theorist towards integrating new observations of neutron star phenomena in constraining dense-matter equations of state.

In this project, the candidate shall use astrophysical observations of neutron stars to constrain the dense-matter EoS. Then using the Bayes statistics, the candidate shall enhance the EoS to align with current neutron star observables. The candidate could place a constraint on neutron star radius by developing a model for a direct comparison between neutron star radii measured via gravitational wave data to X-ray observations of the neutron star radius. The results obtained shall be a viable tool for those using timing irregularities to study neutron star structure and other observables.

Contact Person: Dr. Innocent O. Eya
innocent.eya@unn.edu.ng
Mobile: +234 8039482662
Whatsapp: +234 9080606751

Department of Science Laboratory Technology
University of Nigeria Nsukka
Enugu State
Nigeria

Research Specialization: Astrophysics, Observational, Instrumentation

Title: A Portable Pulsar Detection Radio Telescope operating at 608 – 611 MHz: Design, Construction and Performance

Abstract

Pulsar signals are relatively weak and detected with a very sensitive receiver, at least when compared to that used to detect other radio sources. The first pulsar PSR J1919+21 was discovered by Jocelyn Bell in 1967 with a 16,000 m 2 array of 2000 dipoles tuned to 81.5 M Hz. With the recent introduction of the Software Defined Receivers (SDR) and availability of high performance PCs, this same observation can be carried out today with a relatively small antenna of no more than 2m2 and consisting of no more than 35 dipole elements, However, the detection of pulsar will NOT be in real time as done in professional radio telescopes but the approach is to record the signal and use modern specialised techniques of digital signal processing to increase the Signal-to-Noise Ratio (SNR) and be able to detect the pulses. This project will basically involve the design and construction of a small portable radio telescope (along with its frontends and backends) with processing software capable of collecting sufficient data over a 4 to 6 hour time-frame to detect the brightest pulsars in the northern and southern hemispheres, PSR B0329+54 and PSR B0833-45, in the frequency band 608-611 M Hz.

Briefly, the front-end system will comprise a 2.5 m long 17-element Yagi which will be designed (using the YagiCAD software) and constructed by the student, a 5-element interdigital mechanical filter that will be also designed and constructed, ultra-low noise amplifiers, power dividers and bias tees that will be acquired from reputable radio astronomy equipments manufacturers. For the back-end components, a number of SDRs with at least a bandwidth of 2 MHz and precise internal clocks will be used as the receiver, a PC running Linux will be used for data acquisition and analysis.

Data acquisition softwares will be based on the GNU Radio Consortium while data analysis and validation will be done using PRESTO (PulsaR Exploration and Search TOolkit), a C and python based analysis software primarily designed to efficiently search for binary millisecond pulsars from long observations. This project will serve as a basis for subsequent ones which will be aim at detecting less brighter pulsars by improving the overall system temperature.

Contact Person: Dr. Iyke A. Obi
tonykassidy_z@yahoo.com
NASRDA-Centre for Basic Space Sciences
University of Nigeria Nsukka
Enugu State
Nigeria

Research Specialization: Astrophysics, Star formation

Title: Star formation and AGN activities in nearby star-forming HII galaxies

Abstract

Galaxy formation and evolution involves complex physical processes and understanding how galaxies evolve through cosmic time remains a fundamental question in astrophysical research. Star-formation (SF), one of the most important processes is fundamental to the formation and evolution of galaxies. A measure of the rate of star formation, along with other properties of a galaxy such as the stellar mass, are obtained through fitting SED (spectral energy distribution) models to multi-wavelength spectrophotometric observational data of the galaxy. This allows for SFR calibrations of luminosities at various wavelengths.

The Hα emission line stands out as the best tracer of SF coming from HII regions ionised by massive stars. However such line can also arise from these same massive stars heated by Active Galactic Nuclei (AGN), hence SFR calibrations based on Hα line can be overestimated by the presence of an AGN if the AGN’s contribution is not taken into account.

In this project, our goal is to study the effect of AGN on the SFR of it’s host galaxy. We will use the python-based code, CIGALE (Code Investigating GALaxy Emission), a state-of-the-art galaxy SED-fitting model relying on energy balance, to compute the contribution of an AGN in a self consistent manner in estimating the SFR of a statistical significant sample of nearby star forming galaxies. This will be followed by a comparative analysis of the AGN contributions obtained from other independent methods such as line ratio diagnostic diagrams as well as that obtained with other SED-fitting models. Correlations between the AGN Xray luminosity and SFR will be searched for. The analytical component of the project will also involve some level of computing/modelling.

Contact Person: Dr. Iyke A. Obi
tonykassidy_z@yahoo.com
NASRDA-Centre for Basic Space Sciences
University of Nigeria Nsukka
Enugu State
Nigeria

Research Specialization: Astrophysics, Cosmic rays

Title: Forbush Decrease detection, timing, and magnitude estimation from isolated neutron monitors

Abstract

Forbush decrease (FD), discovered by Scott E. Forbush over eight decades ago, is one of the outstanding transient changes in the intensity of cosmic ray (CR) flux, observed by ground-based neutron monitor (NM) detectors. It is observed as a non-periodic short-term depression in CR intensity, presumed to be associated with large-scale perturbations in the solar wind and the interplanetary magnetic field. FDs are grouped as either sporadic/non-recurrent or recurrent in accordance with the kind of interplanetary medium disturbances that generate them. Sporadic/non-recurrent FDs are those caused by ephemeral interplanetary events associated with coronal mass ejections and their interplanetary counterparts streaming from the Sun. The recurrent FDs result from high-velocity streams from coronal holes corotating with the Sun

FD phenomenon plays a significant role in our understanding of the Sun–Earth electrodynamics as it is being deployed as a mediator parameter in solar-terrestrial superposition analyses. Whereas ground-based NMs register CR counts which are time series data, FD magnitude and timing have to be reasonably calculated. Even though many studies have been devoted to FDs for several decades, accurate timing, and magnitude estimation are yet among the intractable problems in FD investigations. Manual and semi-automated techniques have been commonly employed in estimating the FD magnitudes. Recently, FD timing and magnitude have been successfully automated by our research group.

In this project, the FD selection approach from isolated neutron monitors that incorporates rolling means shall be explored. Consequently, some existing works that employed static averages would be re-analysed in light of the new event catalog. This is expected to yield interesting results that will be of interest to the CR scientist community

Contact Person: Jibrin Alhassan (Ph.D)
jibrin.alhassan@unn.edu.ng
NASRDA-Centre for Basic Space Sciences
University of Nigeria Nsukka
Enugu State
Nigeria

Research Specialization: Astrophysics, Active Galactic Nuclei

Title: The role of γ-ray Emitting Radio AGN in galaxy Evolution and Unification

Abstract

Radio loud active galactic nuclei (AGN) are now known to launch powerful relativistic jets of material, whose energetic output plays a critical role in controlling stellar activities in their surrounding galaxies. However, too large numbers of classes and subclasses of the AGN are identified in literature and great effort of research on AGNs is directed to the development of a unified scheme – theoretical framework in which the differences observed among AGN subclasses can be explained as similar objects observed at either varying orientations of the radio axes to the line of sight or at different cosmic times. While this scheme has been fairly studied in the radio band, a major challenge has been the paucity of high energy data for a vast majority of known radio AGNs

Nevertheless, over the past 12 years, the Fermi large area telescope (Fermi-LAT) has been turning in a lot of γ-ray data on increasing number of known radio AGNs than previously possible. This M.Sc research is aimed at filling up this gap in AGN research by examining the relationship between radio and high energy components of the spectral energy distribution of large samples of the radio AGNs.

The research will employ statistical techniques using Fermi-LAT AGN catalogues, to model the high energy data of the radio AGNs in the light of the unified schemes and evolution of their host galaxies across cosmic time.

Contact Person: Jibrin Alhassan (Ph.D)
jibrin.alhassan@unn.edu.ng
NASRDA-Centre for Basic Space Sciences
University of Nigeria Nsukka
Enugu State
Nigeria

Research Specialization:

Title: Pulsar glitch recoveries and neutron star’s components relative motion.

Abstract

The swift spin-up in the spin frequency of an otherwise gradually decelerating pulsar, known as a pulsar glitch is a direct probe of the dynamics of matter in neutron stars’ interior. After the spin-up in the pulsar spin frequency, which is transient, a relaxation phase follows at which the pulsar restores itself to a gradually decelerating state. The relaxation phase is the glitch recovery and the time it takes the pulsar to relax is the recovery time. A developed neutron star is expected to have layers of superfluid matter in its interior. Direct observation of these layers is not possible with the present-day instruments. To study such a layer, an indirect approach via pulsar glitch analysis is employed. Mechanisms involving the transfer of angular momentum from the superfluid component to the crust are more useful in understanding the pulsar glitch phenomenon. In that, the neutron star superfluid component rotates differentially from the rest of the star enabling it to store angular momentum. The velocity difference of the superfluid to the rest of the star is the differential rotation lag of which the superfluid component is leading. The superfluid rotates via an array of quantized superfluid vortices. These vortices are pinned at the lattice of the inner crust. Anytime the vortices unpin, they transfer their momentum to the bulk of the neutron star leading to a spin-up of the pulsar. After a glitch, a relaxation process known as glitch recovery usually follows. During the relaxation, the pulsar regains a stable spin rate, which could be the same as the pre-glitch spin rate if the pulsar recovered completely. But if the pulsar does not recover completely, a new spin rate which is not the same as the pre-glitch spin rate is attained.

Pulsar glitches are primarily characterized by their sizes and inter-glitch time intervals, while the recoveries are characterized by their pattern and the time constant. Glitch sizes span several orders of magnitude and can vary from event to event, likewise the inter-glitch time intervals. The amount of the spin-up that recover are not similar, it can vary from glitch to glitch likewise the recovery time. The glitch size is an insight into the amount of the transferred momentum, while the inter-glitch time intervals give insight into the rate of accumulation of transferrable momentum.

On the other hand, the state of the rotation lag at the onset of a glitch is essential for the proper estimation of the sizes of the neutron star components pulsar glitches. The lag can either disappear completely or decrease at the onset of glitches. In literature, the state of the lag at the onset of a glitch is usually investigated with a “glitch size – inter-glitch time interval relationship”. Since there is science in that, not considering the effects of glitch recoveries on the pulsar spin parameters is a limitation to it. The number of times a given pulsar has rotated at any given two equal inter-glitch time intervals are not the same if the pulsar did not recover completely in the given glitches. As such, the inter-glitch time interval is not a complete measure of the rate of accumulation of transferable momentum.

In this project, we shall investigate the glitch size – inter-glitch time interval relationship from a different approach using the number of times pulsar rotated before a given glitch. This approach will take care of incomplete recovery/new spin rate for which the inter-glitch time intervals couldn’t account for. In addition, using the glitch recovery parameters, we shall model the moment of inertia of the superfluid component, and study its distribution with respect to recovery time to ascertain a possible connections.

Contact Person: Dr. Innocent O. Eya
innocent.eya@unn.edu.ng
Mobile: +234 8039482662
Whatsapp: +234 9080606751

Department of Science Laboratory Technology
University of Nigeria Nsukka
Enugu State
Nigeria

Title: Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) classification of mine tailings in Southern Africa

Abstract

The project aims to build a national scale inventory and characterisation of mine tailings from active and closed mines in South Africa, in a form of a geospatial GIS database. Studies of this nature have not been reported in the literature in South Africa. Therefore, this project will generate a tangible outcome in a form of a database that will be available to the public and represents the groundwork for future research.

Surface mine tailings are the most visible legacy of the mining activity, which played and continues to play a pivotal role in the economic development of Southern Africa. Due to the large volume of material and land coverage, they can be seen from space and easily studied in satellite images via remote sensing. The detailed study and combination of available, free, high-resolution multispectral and hyperspectral data, such as the advanced spaceborne thermal emission and reflection radiometer (ASTER) together with the analusys of Sentinel-2 (Copernicus Programme), and PRISMA (PRecursore IperSpettrale della Missione Applicativa, Italian Space Agency) offer an ideal and robust tool in discriminating lithologies and in regional mapping.

In South Africa there are many mine tailings, and most of them are are not monitored or even mapped. The minerals and rocks exposed and accumulated in mine tailings pose a significant risk to the surrounding environment as a source of heavy metals pollution, due to exposure to wind and rain. In turn, mine waste also offers a new mining opportunity, contributing to the mine value chain and extending the life of mines. All over the world, there is a rising interest in mine tailings as they may host critical metals (such as Cu, Co, REE, Ge, and U), which represent the building blocks for a clean and digitized economy. Southern Africa should capitalise on this increasing global demand for critical minerals, and quickly secure a position in shifting supply chains for long-term economic growth and prosperity.

Contact Person: Dr Linda Iaccheri
linda.iaccheri@wits.ac.za
University of the Witwatersrand
School of Geosciences
Johannesburg
South Africa

Title: Digitisation Of The Astronomical Plate Archive Of The South African Sky

Abstract

The Astronomical Plate Archive of the South African Sky, comprising dozens of historically important photographic plates taken at the Johannesburg Observatory dating back to 1909, is now based in the School of Physics at Wits. In order to maximise the potential of this invaluable data archive for scientific research, the contents of the plates must be digitised and rendered into a modern, open data format accessible to scientists worldwide.

Wits has begun the process of producing calibrated digital photographs of the plates and digitising the contents of the associated log books. What is needed is an automated process that can transform the digitised contents of the plates and log books into data formatted with astronomically relevant metadata and images compatible with resources such as the Virtual Observatory and other scientific open access databases. This MSc project will be to research the appropriate data format and algorithms and to develop and deploy the automated proces that will transform the raw data of the digitised plate archive into a valuable and globally accessible resource for astronomical research.

Contact Person: Prof Andrew Chen
andrew.chen@wits.ac.za
Wits Centre for Astrophysics
University of the Witwatersrand
Johannesburg
South Africa

Title: How To Discover Dark Matter Properly

Abstract

If we go hunting for dark matter with MeerKAT and we actually see a potential signal, how would we determine that it really is dark matter? After all, it could originate from a variety of faint baryonic emissions. Dwarf galaxies are ideal dark matter testbeds with high dark matter densities and low backgrounds (no diffuse radio emission observed to date). They would, however, have radio signals from low-level star formation. This project would involve simulating star formation emission in dwarf galaxies, using theoretical models, and evaluating strategies for the extraction of a dark matter signal in its presence. This would be the first work of its kind undertaken for dark matter searches and would lead to a journal article. This would be an MSc project supervised by Dr G Beck and Dr S Makhathini. This project could be developed into PhD work by considering other sources with faint radio backgrounds like radio-poor spiral galaxies and galaxy clusters.

Contact Person: Dr Geoffrey Beck
geoffrey.beck@wits.ac.za
University of the Witwatersrand
Johannesburg
South Africa
Contact Person: Dr Sphesihle Makhathini
sphesihle.makhathini@wits.ac.za
University of the Witwatersrand
Johannesburg
South Africa

Title: MULTI-WAVELENGTH STUDY OF LARGE-SCALE OUTFLOWS FROM NGC 1068 – Search for Fermi-bubble like structures in galaxies

Abstract

NGC 1068 is a composite starburst/Seyfert galaxy that exhibits circumnuclear outflow. We investigate whether they originate from nuclear star formation activity or if they are jets from an active galactic core. High-resolution radio observations allow us to study the morphology of the circumnuclear region of NGC 1068. In this work, a multi-wavelength analysis of this system is conducted using the available radio observations and Fermi-LAT data, to aid in the understanding of the origin of these structures. These results are also compared to the star-formation driven Fermi bubbles in the Milky Way, which have been observed in both the gamma-ray and the radio bands, to determine physical similarities between these structures.

Contact Person: Prof Andrew Chen
andrew.chen@wits.ac.za
Wits Centre for Astrophysics
University of the Witwatersrand
Johannesburg
South Africa

Title: MULTI-WAVELENGTH STUDY OF LARGE-SCALE OUTFLOWS FROM NGC 3079

Abstract

NGC 3079 is a starburst-Seyfert galaxy with a prominent circumnuclear superbubble structure. We investigate whether the bubble originates from nuclear star formation activity or from an active galactic nucleus. High-resolution radio observations allow us to study the morphology of the circumnuclear region of NGC 3079. In this work, a multi-wavelength analysis of this system is conducted using the available multiwavelength data, to aid in the understanding of the origin of these structures. These results are also compared to the star-formation driven Fermi bubbles in the Milky Way, which have been observed in both the gamma-ray and the radio bands, to determine physical similarities between these structures.

Contact Person: Prof Andrew Chen
andrew.chen@wits.ac.za
School of Geoscience,
University of the Witwatersrand
South Africa

Title: A SET OF APIS TO INTERFACE QUARTICAL AND WSCLEAN TO APACHE PARQUET FILES ON A REMOTE STORAGE SERVER

Abstract

The CASA-table based measurement set (MS) database has served the community well over the decades, providing a standardized interface for radio astronomy data. However, since the format is so specialized for radio data it does not interface well with storage layer tools such as Delta Lake and Snowflake. These tools provide ACID transactions, scalable metadata handling, and facilitate distributed computing. Moreover, these tools are also supported by large organizations like AWS, Google, Apache, and Microsoft. For this project, we will write a set of APIs to interface the WSClean and the QuartiCal software applications to a remote storage based on the Apache Parquet database format and the Delta Lake storage layer. The aim is to gauge the performance of this storage ecosystem, especially in the context of distributed computing.

Contact Person: Dr Sphesihle Makhathini
sphesihle.makhathini@wits.ac.za
University of the Witwatersrand
Johannesburg
South Africa

Research Specialization: Planetary Science

Title: Morokweng Impact Structure

Abstract

The ~80 km wide Late Jurassic Morokweng impact structure, which is buried beneath Kalahari Group sediments in South Africa’s North West province, is one of the 7 largest impact craters found on Earth and is relatively poorly understood owing to its inaccessibility. Previous work includes petrological, structural and geochemical investigations of several borehole cores, which include one of the thickest intersections of a differentiated impact melt sheet. Original estimates of the crater morphology were made from a regional magnetic dataset. Subsequently, unpublished high-res aeromagnetic data were flown by Falconbridge over the impact crater for mineral exploration purposes,  but not interpreted further.

This study will involve the measurement of petrophysical properties of the 1100 m M3 and 370 m M4 drill cores to investigate the density and seismic velocity associated with the thick, heterogeneous melt sheet and highly deformed crater basement, respectively. A magnetic model will also be created to evaluate the Falconbridge dataset and previous geophysical interpretations.

Contact Person: Prof. Roger Gibson
roger.gibson@wits.ac.za
School of Geosciences
University of the Witwatersrand
Johannesburg
South Africa
Contact Person: Dr Stephanie Enslin
stephanie.scheiber@wits.ac.za
School of Geosciences
University of the Witwatersrand
Johannesburg
South Africa