Here are some potential projects for MSc students in 2021. Projects are grouped into observational,
computational/modelling and construction/instrumentation. This project list will be continuously
updated over time. Students can as well contact the supervisor(s) for other projects ideas he/she
might have
- – 3D Map of the Milky Way Galaxy at 21cm with the CSRT
Project Description
The CBSS’s Small Radio Telescope (CSRT) is located at Egbirimirri Umuakashi, Nsukka in
Enugu State of Nigeria (6◦50’ 14” Lat, 7◦21’ 11” Long). It comprises a 3m-diameter parabolic
mesh dish with a prime focus feed system, a cylindrical 1420MHz feed horn based on a VE4MA
feed design and a rotor that moves the dish in elevation and azimuth. The front-end electronics
consist of low noise amplifiers and band pass filters while the back-end receiver system is
temporarily based on software defined radio (SDR). The 21cm (1420.405 MHz) line produced by
clouds of neutral hydrogen in the interstellar medium is the most important and significant
spectral lines in radio astronomy. It provides radio astronomers with a very useful probe for
studying the differential rotation of spiral galaxies. Through the observation of the line at
galactic longitudes along our galactic plane one can show that the angular velocity increases as
you look at points closer to the galactic center. The aim of the project is two-fold (a) to produce
a rotational curve for our galaxy using the 21-cm spectral lines observations obtained at different
galactic longitudes along the galactic plane (galactic latitude of 0 ◦) (b) to create a 3D-map by
performing such observations at several galactic-longitudes and different galactic latitudes.
Observations will be planned using the software, Stellarium and Radio Eyes while data
acquisition and analysis will be made using a python program based on the GNU Radio
Consortium.
Supervisor(s): Dr I.A. Obi
Prior knowledge: Basic astronomy knowledge, in particular celestial coordinate system
Estimated Duration: 4 – 6 months
Category: Observational, Computational - – Daily Drift Solar Observations with the CSRT during solar minimum
Project Description
December 2019 marked the beginning of a new solar cycle. The Sun is currently in a quiescent
phase called solar minimum and therefore we expect no or little flares. In this project, we will
make with CSRT, daily measurements of the Sun’s flux during this quite phase at frequencies of
1420 MHz and 1415 MHz and for a period of 3 months. Thereafter, we will search for (a)
correlations of our data with solar X-ray data readily available through the National Oceanic
and Atmospheric Administration (NOAA) and (b) solar flare events and possible correlations
with the above-mentioned solar x-ray data. Observations in literature, both during a period of
high solar (solar maximum) and low solar activities (solar minimum), has reported correlations
between solar events and x-ray data. This project will demonstrate the kind of solar science that
can be executed with CSRT and it’s conclusion will serve as a basis for future work. If time will
permit, this study will be complemented with solar visual observations that will be made with
the CBSS’s 10cm Lunt Solar Telescope.
Supervisor(s): Dr I.A. Obi
Prior knowledge:
Estimated Duration: 4 – 6 months
Category: Observational - – Star formation and AGN activities in nearby star-forming HII galaxies
Project Description
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.
Supervisor(s): Dr I.A. Obi
Prior knowledge:
Basic knowledge of any computer programming language (preferably python), Unix-based
command line, Stellar evolution theory.
Estimated Duration: 6 – 12 months
Category: Computational/Modelling - – Dust attenuation properties of high-redshift star-forming galaxies
Project Description
Modelling the spectral energy distributions (SED) of galaxies is commonly used to obtain
physical properties such as stellar and dust masses , star formation rate. The technique used is
population synthesis where the stellar emission coming from the various stellar populations (with
different ages and chemical compositions) of a galaxy is reconstructed, while assuming star
formation histories of varying complexity. However, dust plays a critical role by adversely
affecting and reshaping the original SED of stars by absorbing (the UV-optical wavelengths) and
scattering stellar photons and thermally emitting the absorbed energy in the infrared. This effect
of dust must be accounted for and this is done with dust models which mainly follow two
approaches, one that assumes that all energy absorbed by dust is radiated in the infrared (eg
CIGALE) and accounts for dust absorption and remission using simple attenuation laws and one
that, without any prior assumption of attenuation law, theoretically solves the radiative transfer
equation. Determining the shape and strength of the attenuation law is one of the most difficult
task in astrophysics and there is a strong evidence that this law could be different in different
environments. In this work we will use the fortran-based radiative transfer code GRASIL
(GRAphites and SILicates) which uses the most recent database of PARSEC (PAdova TRieste
Stellar Evolutionary Code) evolutionary tracks of massive stars to predict the panchromatic SED
(including Hα emission lines) of selected high redshift star forming galaxies. We will carry out
an investigation of the effect of environment on dust attenuation.
Supervisor(s): Dr I.A. Obi
Prior knowledge:
Basic knowledge of any computer programming language (preferably python), Unix-based
command line, Stellar evolution theory.
Estimated Duration: 6 – 12 months
Category: Computational/Modelling