Department of Physics
http://umoar.mu.edu.mm/handle/123456789/10
2017-09-25T06:13:41ZDoes Σ-Σ-α Form a Quasi-Bound State?
http://umoar.mu.edu.mm/handle/123456789/171
Does Σ-Σ-α Form a Quasi-Bound State?
Htun Htun Oo; Khin Swe Myint; Kamada, Hiroyuki; Gloeckle, Walter
We have investigated the possible existence of a quasi-bound state for the Σ-Σ-α system in the framework of Faddeev calculations. We are particularly interested in the state of total iso-spin T = 2, since for an inert α particle there is no strong conversion to Ξ-N-α or Λ-Λ-α possible. A Σ-α optical potential based on Nijmegen model D and original Σ-Σ interactions of the series of Nijmegen potentials NSC97 as well a simulated Gaussian type versions thereof are used. Our investigation of the Σ-Σ-α system leads to a quasi bound state where, depending on the potential parameters, the energy ranges between −1.4 and −2.4 MeV and the level width is less than 0.4 MeV.
2005-01-01T00:00:00ZStructure Analysis of Light [I] - Hypernuclei
http://umoar.mu.edu.mm/handle/123456789/98
Structure Analysis of Light [I] - Hypernuclei
Phyo Wai Wai Lwin; Aye Aye Min; Khin Swe Myint
In this research work, the binding energies of light ; hypernuclei namely ; -
12C, ; -
14N and ; -
16O have been calculated within the frame work of ; single-particle model by solving
nonrelativistic Schrödinger equation. In this calculation, the Gaussian basis wave function and
phenomenological Woods-Saxon central potential including coulomb interaction are used. By
using the strength of Woods-Saxon potential -14.0 MeV, the calculated bound state energy of ; -
14N is 3.07 MeV over binding than the recent experimental results, 4.38 r 0.25 MeV which
is observed from E373 experiment, KEK, Japan. Therefore, the binding energies of ; -
14N
have investigated by varying potential strength. At the potential depth -8.5 MeV, the calculated
binding energy of ; -
14N is in good agreement with the experimental result. Therefore, this
potential strength is applied to study the structure analysis of other two light ; hypernuclei.
The observed binding energies of 1S state for ; -
12C and ; -
16O are 3.64 MeV and 5.09 MeV
respectively. In addition, the root-mean-square radii of these light ; hypernuclei have also
investigated. The calculated results are 3.24 fm for ; -
12C, 3.11 fm for ; -
14N and 3.02 fm
for ; -
16O respectively. It is also found that 3D and 4F states are only pure ; - atomic states
while the other S and P states are Coulomb-assisted nuclear ; -bound states called hybrid
states.
2016-01-01T00:00:00ZRed Spinach Dye Extracts as Photosensitizer in Solid State Dye Sensitizer Dye Solar Cells : Varying Relative Ratio of Co-solvents and Dye Extracting Temperature
http://umoar.mu.edu.mm/handle/123456789/97
Red Spinach Dye Extracts as Photosensitizer in Solid State Dye Sensitizer Dye Solar Cells : Varying Relative Ratio of Co-solvents and Dye Extracting Temperature
Nan Kyi Kyi Thein; Than Zaw Oo
The natural dye solutions were extracted from red Spinach leaves and used as photosensitizer
in solid-state dye-sensitized solar cells (ssDSSCs). The optimal conditions for dye
concentration and extracting temperature in ethanol and relative concentration of co-solvents
(DMF and EtOH) were explored. With optimal dye concentration, the dyes extracted at 60 ºC
in ethanol and the dyes in DMF-rich solvent maximized the absorption of dye solutions.
Following the study of dye absorption in solution, ssDSSCs were fabricated using red spinach
dye extracts and their photovoltaic performances were examined against dye extracting
temperature and relative ratio of co-solvents. It is found that the device efficiencies were
insensitive to extracting temperature and a relatively higher efficiency of 0.10% was exhibited
in the device with red spinach dye in ethanol.
2016-01-01T00:00:00ZFabrication of Titanium Dioxide Nanotubes Array For Photoanode in Mesoscopic Solar Cells
http://umoar.mu.edu.mm/handle/123456789/96
Fabrication of Titanium Dioxide Nanotubes Array For Photoanode in Mesoscopic Solar Cells
Min Min Thein; Min Khant Ko; Hlaing Min; Nyein Wint Lwin; Than Zaw Oo
One dimensional (1D) nanostructures have been attracting the research interest and have many
potential applications including mesoscopic solar cells. In this work, 1D titanium dioxide
(TiO2) nanotubes array have been fabricated by the electrochemical anodization of Ti foils in
electrolyte. Focus was placed on the morphology and size control of TiO2 nanotubes by
varying fluoride content in electrolyte (0.3-0.6 Wt%). Fluoride contents of 0.4 and 0.5 Wt%
are optimum for production of well-defined nanotubes array with uniform size distribution
(tube diameter of 100 - 140 nm). It is also observed that higher the fluoride concentration, the
larger is the anodization current across the sample. The tube morphology and size are strongly
sensitive to the fluoride content in electrolyte.
2016-01-01T00:00:00Z