Browsing Natural and Agricultural Sciences by Author "10060499 - Van der Walt, Diederick Johannes (Supervisor)"
Now showing items 1-13 of 13
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Application of spectral analysis techniques on the gamma–ray data of Vela X–1 and PKS 2155–304
Van der Schyff, Augusts Eric. (North-West University, 2012)Studies of frequency variability can provide an important understanding of physical processes in the central regions of an AGN (Ulrich et al., 1997). For neutron star y–ray sources, variations in the intrinsic pulse frequency ... -
Formation of prebiotic hydrogen cyanide dimers in an astrophysical environment
Els, Paul Lodewyk (North-West University (South Africa), 2019)The past half-century has seen much advancement in the fields of astronomy and astrochemistry, but an emerging and highly interdisciplinary field, known as astrobiology, now seeks to answer one of the oldest and most ... -
An investigation into maser variability in high-mass star forming regions
Maswanganye, J.P. (North-West University, 2018)The two brightest class II methanol masers - at 6.7- and 12.2-GHz, are exclusively associated with the early phases of high-mass star formation. This implies that studying these maser species is an indirect probe of the ... -
An investigation into the variability of methanol and hydroxyl masers in the star-forming region G12.89+0.49
Langa, Mihloti Christina (North-West University, 2006)It is now widely accepted that 6.7 GHz and 12.2 GHz class I1 methanol masers are signposts of very young high mass star-forming regions. The exact location of these masers is still a matter of debate, they may be in disks ... -
Multi-scale study of massive star forming region NGC 6334I/F
Vorster, Jacobus Marthinus (North-West University (South Africa), 2023)This thesis reports an observational multi-scale study of the high-mass star-forming region NGC6334I=F on scales ranging from 10 000 AU down to 1 AU. In 2015, NGC6334I-MM1B started a period of high accretion analogous ... -
A multi-wavelength study on the low-mass stellar populations of the southern high-mass star-forming regions RCW 34 and NGC 2626
Czanik, R.J. (North-West University, 2019)The physical processes of how stars form is well understood and documented. However, the finer details of how high-mass stars (M > 8 Mꙩ) form is not yet fully known. High-mass stars are usually associated with class II ... -
An optical study of the high mass star forming region RCW 34
Czanik, Robert Johann (North-West University, 2013)This study consisted of an optical photometric and spectroscopic analysis on a 7′ 7′ field around the Southern high mass star forming region RCW 34. A previous study on RCW 34 in the NIR discov- ered many deeply embedded ... -
Periodic methanol masers and colliding wind binaries
Van den Heever, S.P. (North-West University, 2017)The process by which massive stars form is not yet fully understood. Since massive stars are rare, and generally found at great distances from the Sun, it is difficult to study them and their influence on their environment ... -
Search for optically visible clusters associated with methanol masers
Nyambuya, Golden Gadzi (North-West University (South Africa), 2002)We present a pilot study of the massive star formation region G 264.29+ 1.4 7. A photometric and a two-point correlation function study of this region has been carried out in order to find out whether or not there is ... -
A search for pulsating B–type variable stars in the southern open clusters NGC 6204 and Hogg 22
Mentz, Jacobus Johannes (North-West University, 2013)The theory of stellar evolution and stellar structure relies on the observation of stars in di erent phases of their evolutionary cycle. The relation between observations and theory can be strengthened by obtaining ... -
A search for radio recombination lines in selected ultra-compact HII regions
Molebatsi, Potso Treasure (North-West University (South Africa), 2020)The role that high-mass stars play in galaxies is significant. They strongly affect their environment through their strong ultraviolet radiation, powerful winds, and supernova explosions. The physical processes that control ... -
Sub-millimetre observations of periodic methanol maser sources
Morgan, J. (North-West University, 2019)One of the properties of high-mass star forming regions is that they are associated with masers. A small group of these star forming regions contain periodic methanol masers. A significant aspect of the periodic methanol ... -
Variability of methanol and OH masers associated with the star forming region G339.62-0.12
Seidu, Mavis (North-West University (South Africa), 2020)Astrophysical maser emission from various molecules and in a number of astrophysical environments is now a well-known phenomenon. Since the first discovery of hydroxyl (OH) maser emission by Weinreb et al. (1963), the use ...