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003			EG-GiCUC
005			20250223031708.0
008			170326s2016 ua d f m 000 0 eng d
040			_aEG-GiCUC _beng _cEG-GiCUC
041	0		_aeng
049			_aDeposite
097			_aM.Sc
099			_aCai01.24.05.M.Sc.2016.Mo.R
100	0		_aMohamed Ahmed Abdelati Abdeltawwab
245	1	0	_aRole of physical processes in the production of sodium plasma by laser Ionization based on resonance saturation / _cMohamed Ahmed Abdelati Abdeltawwab ; Supervised Yosr Ezz Eldin Gamal , Mohamed Abdelhamid Mahmoud
246	1	5	_aدور العمليات الفيزيائية فى انتاج بلازما الصوديوم بواسطة التاين بالليزر المرتكز على التشبع الرنينى
260			_aCairo : _bMohamed Ahmed Abdelati Abdeltawwab , _c2016
300			_a95 P. : _bcharts ; _c25cm
502			_aThesis (M.Sc.) - Cairo University - National Institute of Laser Enhanced Sciences - Department of Laser Applications in Environmental Metrology Photochemistry and Agriculture Culture
520			_aThis work is based on the modification of a previously developed model by (Mahmoud and Gamal, 1995). This model was initially developed to study theoretically the time evolution of the energy distribution of free electrons created by collisional ionization of sodium vapor resonantly excited with CW laser due to different physical mechanisms basing on laser Ionization based on resonance saturation (LIBORS) technique. The modification is devoted to include into the model an ionization process which acts to increase the seed electrons density namely tri-atomic associative ionization process. The cross section of this process was determined experimentally by tapalian and smith (tapalian and smith, 1993) in their measurements of the trimer ion yield in sodium vapor. In this experiment two continuous dye lasers are tuned to the transitions Na (3s)-Na (3p) (589 nm) and Na(3p)-Na (4d) (569 nm) at intensities of up to 100 W/cm2. Under these conditions associative ionization (AI) processes involving high energy states (Na(4d), Na(5s)) are studied, for example AI collision of Na(4d) atoms with Na2 ground state molecule (present at {u2248} 0.5% percent in the atomic beam) resulting in Na3+ trimer ions. Accordingly an additional term refers to this process is included into the numerical model. This in turn implied the modification of the rate equations which describes the variation of the excited states population, ion currents as well as the electron energy distribution function (EEDF). Following to this modification the model is applied first to calculate the tri-atomic ions current against the density of the sodium vapor for different exposure time intervals taken into account the experimentally determined cross section given by tapalian and smith
530			_aIssued also as CD
653		4	_aPhysical processes
653		4	_aResonance saturation
653		4	_aSodium plasma
700	0		_aMohamed Abdelhamid Mahmoud , _eSupervisor
700	0		_aYosr Ezz Eldin Gamal , _eSupervisor
856			_uhttp://172.23.153.220/th.pdf
905			_aNazla _eRevisor
905			_aSamia _eCataloger
942			_2ddc _cTH
999			_c60426 _d60426