Millimeter and radio observational study of Massive Star Forming Region G323.459-0.079 Using MeerKAT and ALMA Data

Project Description: 

High-mass star formation is one of the most promising research areas in astronomy. However, their early formation processes remain poorly understood from an observational point of view. This is because massive protostars are rarely observed, evolve quickly, located at far distance and continue to accrete even in their main-sequence stage. Within the last two decades, observational studies of high-mass stars have advanced considerably due to significant increase in the number of sensitive, high resolution data sets available at mid-infrared, millimetre and submillimetre wavelengths. Unlike the low-mass star formation, the observed evolutionary stages of high-mass star formation are still under debate. High-mass star formation is mostly believed to evolve into four stages namely: infrared dark clouds, high-mass protostellar objects, hot molecular cores and HII regions. One of the science goals of SARAO MeerKAT Galactic Plane Survey (SMGPS) is to identify HII regions, which are high-mass star forming regions. G323.459-0.079 is one of the known HII regions identified in the SMGPS and a good source to explore ongoing high-mass star formation processes such as outflows, rotating structures (disk or envelope) and episodic accretion. The radio continuum properties of G323.459-0.079 such as the ionizing photon rate and dynamical age, which provide information about the ionized gas within the environment of massive forming stars will be obtained from the MeerKAT data. The ALMA data will provide the dust continuum (size and mass) and kinematic (outflows or disks) properties of the region. The study will provide an improved understanding of the observational sequence of evolution of high-mass stars and attempt reconstructing the evolutionary stages. The procedures will involve calibrating and re-imaging of ALMA data using CASA, extracting the radio and dust continuum properties, such as the integrated flux and peak intensity, analyzing spectral line data, which includes modelling and identification of lines using MADCUBA package, carrying out rotation-diagram analysis, creating moment maps and PV-diagrams using CASA, carrying out Keplerian fitting with SpectralCube and pvextractor packages, calculating the physical properties, such as the core mass and column density, estimating the outflow mass, momentum, energy and the driving force of outflows, as well as estimating the ionized gas properties, such as the Lyman ionization flux, brightness temperature, dynamical age, emission measure, electron density and mass. The IDIA/ilifu cloud computing facilities will be accessible to the student for the purpose of calibration, imaging and analysis of the data. The IDIA support team and other researchers are always available to interact and assist the students in the computing aspect. The student will have usual access to other facilities like desk and office space, internet and library. High level breakdown of activities: · - Extensive literature review on massive star formation and HII regions (2027) · - Calibrate and image the data (2027) · - Analyse the data (2027) · - Calculate the millimeter and radio properties (2028) · - Write up thesis (2028) This project falls under the highest priority area: MeerKAT for science. The project will provide a deep look into the properties of one of the sources (G323.459-0.079) observed in SMGPS. The project will utilise data from SMGPS, which is already available in the archives and repository. Good python programming skills and experience in the use of CASA software will be an added advantage. However, students without prior skills and experience will acquire the skills during the course of study.(NWU)

Supervisor

University of South Africa (Unisa)

Co-Supervisor