120 research outputs found
Spektroskopsko prouÄavanje laserom izazvane disprozijeve plazme
We report the observations of the excimer laser-induced dysprosium plasma. The time evolution of DyI and DyII selected resonance line intensities and line widths was studied. It is found that the time development of the plasma plume can be significantly influenced by the presence of argon backing gas. The comparison of the measurements of dysprosium atomic line widths made in vacuum and in argon shows a small influence of argon on the measured Stark line widths.Opisuje se prouÄavanje laserom stvorene disprozijeve plazme. Istraživala se vremenska ovisnost jakosti i Å”irina izabranih rezonantnih linija DyI i DyII. Opazili smo da na vremenski razvoj plazme jako utjeÄe prisutnost argona. Usporedba Å”irina linija DyI izmjerenih u vakuumu i u argonu pokazuje malen utjecaj na mjerene Starkove Å”irine linija
Spektorskopska svojstva plazme metala litija i cinka i LiāZn legura proizvedenih ablacijom pomoÄu XeCl lasera
Using 308 nm laser ablation, we have produced lithium, zinc and lithium-zinc plasmas and have studied their spectral, temporal and spatial characteristics. In pure lithium plume, linear Stark effect is observed in n2D-2 2P transitions n = 3, 4, 5, 6) up to 0.3 Ī¼s after the laser pulse. In pure zinc plume, both atomic and ionic spectral lines are observed. Time evolution of spectral line intensities suggests that the mechanism responsible for population of atomic zinc states is a cascade of ion-electron recombination processes. The ablation of Li-Zn alloy shows much faster decay of Zn spectral features than of Li spectral lines. Therefore, the decomposition of plume into shells of different colours is observabProuÄavali smo spektralna, vremenska i prostorna svojstva litijeve, cinkove i litij-cink plazme stvorene ablacijom pomoÄu lasera na 308 nm. Kod Äistog litija opažen je pri n2 D2 -22 P prijelazima (n = 3, 4, 5, 6) linearni Starkov efekt u vremenu do 0.3 Ī¼s nakon laserskog pulsa. Kod Äistog cinka opažene su i atomske i ionske spektralne linije. Na temelju vremenske evolucije intenziteta spektralnih linija može se zakljuÄiti da je mehanizam naseljavanja pobuÄenih stanja atoma cinka kaskada rekombinacijskih procesa izmeÄu iona i elektrona. Pri ablaciji litij-cink slitine opaženo je mnogo brže guženje zinkovih spektralnih pojava nego litijevih. To je glavni razlog razdvajanja oblaÄka litij-cink plazme u ljuske razliÄitih boja
Spektroskopsko prouÄavanje laserom izazvane disprozijeve plazme
We report the observations of the excimer laser-induced dysprosium plasma. The time evolution of DyI and DyII selected resonance line intensities and line widths was studied. It is found that the time development of the plasma plume can be significantly influenced by the presence of argon backing gas. The comparison of the measurements of dysprosium atomic line widths made in vacuum and in argon shows a small influence of argon on the measured Stark line widths.Opisuje se prouÄavanje laserom stvorene disprozijeve plazme. Istraživala se vremenska ovisnost jakosti i Å”irina izabranih rezonantnih linija DyI i DyII. Opazili smo da na vremenski razvoj plazme jako utjeÄe prisutnost argona. Usporedba Å”irina linija DyI izmjerenih u vakuumu i u argonu pokazuje malen utjecaj na mjerene Starkove Å”irine linija
Spektorskopska svojstva plazme metala litija i cinka i LiāZn legura proizvedenih ablacijom pomoÄu XeCl lasera
Using 308 nm laser ablation, we have produced lithium, zinc and lithium-zinc plasmas and have studied their spectral, temporal and spatial characteristics. In pure lithium plume, linear Stark effect is observed in n2D-2 2P transitions n = 3, 4, 5, 6) up to 0.3 Ī¼s after the laser pulse. In pure zinc plume, both atomic and ionic spectral lines are observed. Time evolution of spectral line intensities suggests that the mechanism responsible for population of atomic zinc states is a cascade of ion-electron recombination processes. The ablation of Li-Zn alloy shows much faster decay of Zn spectral features than of Li spectral lines. Therefore, the decomposition of plume into shells of different colours is observabProuÄavali smo spektralna, vremenska i prostorna svojstva litijeve, cinkove i litij-cink plazme stvorene ablacijom pomoÄu lasera na 308 nm. Kod Äistog litija opažen je pri n2 D2 -22 P prijelazima (n = 3, 4, 5, 6) linearni Starkov efekt u vremenu do 0.3 Ī¼s nakon laserskog pulsa. Kod Äistog cinka opažene su i atomske i ionske spektralne linije. Na temelju vremenske evolucije intenziteta spektralnih linija može se zakljuÄiti da je mehanizam naseljavanja pobuÄenih stanja atoma cinka kaskada rekombinacijskih procesa izmeÄu iona i elektrona. Pri ablaciji litij-cink slitine opaženo je mnogo brže guženje zinkovih spektralnih pojava nego litijevih. To je glavni razlog razdvajanja oblaÄka litij-cink plazme u ljuske razliÄitih boja
Bose-Einsteinova kondenzacija u razrijeÄenim parama: novo makroskopsko kvantno stanje materije
Nastanak 7LiCd u Cd+7Li2 (F1Ī£ + g ) reakciji
Blue-green excimer band of 7LiCd was observed as a result of 7Li2(F 1Ī£+g)+Cdā7LiCd(2 2Ī )+Li photochemical reaction. Lithium dimer was excited into F1Ī£+g by using opticalāoptical double resonance excitation with single dye laser photons in the 615 ā 671 nm range where a number of accidental resonances (X1Ī£+g āA1Ī£+u āF1Ī£+g) occur. The reactivity of the excited gerade state in the formation process of the intermetallic excimers is comparable to reactivity of the ungerade states.Plavozelene vrpce 7LiCd eksimera opažene su kao rezultat 7Li2(F 1Ī£ + g )+Cdā 7LiCd(2 2Ī ) + Li fotokemijske reakcije. Litijev dimer se pobuÄivao u F1Ī£ + g stanje pomoÄu optiÄkoāoptiÄku dvostruku rezonanciju fotonima dyeālasera u podruÄju izmeÄu 615 i 671 nm, gdje se nalaze brojne sluÄajne rezonancije (X1Ī£ + g ā A1Ī£ + u ā F 1Ī£ + g ). Reaktivnost pobuÄenog parnog gerade stanja u procesu formiranja intermetalnih eksimera je vrlo sliÄna (usporediva) s reaktivnoÅ”Äu neparnih (ungerade) stanja litijeve molekule
Nastanak 7LiCd u Cd+7Li2 (F1Ī£ + g ) reakciji
Blue-green excimer band of 7LiCd was observed as a result of 7Li2(F 1Ī£+g)+Cdā7LiCd(2 2Ī )+Li photochemical reaction. Lithium dimer was excited into F1Ī£+g by using opticalāoptical double resonance excitation with single dye laser photons in the 615 ā 671 nm range where a number of accidental resonances (X1Ī£+g āA1Ī£+u āF1Ī£+g) occur. The reactivity of the excited gerade state in the formation process of the intermetallic excimers is comparable to reactivity of the ungerade states.Plavozelene vrpce 7LiCd eksimera opažene su kao rezultat 7Li2(F 1Ī£ + g )+Cdā 7LiCd(2 2Ī ) + Li fotokemijske reakcije. Litijev dimer se pobuÄivao u F1Ī£ + g stanje pomoÄu optiÄkoāoptiÄku dvostruku rezonanciju fotonima dyeālasera u podruÄju izmeÄu 615 i 671 nm, gdje se nalaze brojne sluÄajne rezonancije (X1Ī£ + g ā A1Ī£ + u ā F 1Ī£ + g ). Reaktivnost pobuÄenog parnog gerade stanja u procesu formiranja intermetalnih eksimera je vrlo sliÄna (usporediva) s reaktivnoÅ”Äu neparnih (ungerade) stanja litijeve molekule
Vremenski razvoj intermetalnih difuznih spektara
LiZn and LiCd vapour mixtures prepared in the heat-pipe oven are irradiated with pulsed excimer laser emission at 308 nm. Temporal evolution of the fluorescence spectra is observed showing that different processes occur such as multiphoton excitation, collisional energy transfer, photochemical reaction, relaxation etc. Temporal change of the LiZn and LiCd blue-green diffuse bands spectral shape is observed and interpreted in terms of previous spectral simulations. The effective lifetimes of different spectral features are determined.MjeÅ”avine para Li-Zn i Li-Cd pripremili smo u toplovodnim peÄima i obasjavali pulsnim excimerskim laserom na 308 nm. Opažanje vremenskog razvoja fluorescentnih spektara pokazalo je postojanje razliÄitih procesa kao Å”to je multifotonska pobuda, sudarni prijenos energije, fotokemijska reakcija, relaksacija itd. Opaženu vremensku promjenu spektralnog oblika plavo-zelenih difuznih vrpci LiZn i LiCd molekula objasnili smo pomoÄu ranijih svojstava spektralnih simulacija. Odredili smo efektivna vremena života razliÄitih spektralnih pojava
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