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This paper presents an extensive parameter study of a non-intrusive and non-seeded laser diagnostic method for measuring one dimensional (1D) rotational temperature of molecular nitrogen (N2) at 165 - 450 K. Compared to previous efforts using molecular oxygen, here resonantly ionized and photoelectron induced fluorescence of molecular nitrogen for thermometry (N2RIPT) was demonstrated. The RIPT signal is generated by directly probing various rotational levels within the rovibrational absorption band of N2, corresponding to the 3-photon transition of N2(X1Σg+,v=0→b1Πu,v′=6) near 285 nm, without involving collisional effects of molecular oxygen and nitrogen. The photoionized N2produces strong first negative band of N2+(B2Σu+−X2Σg+) near 390 nm, 420 nm, and 425 nm. Boltzmann analyses of various discrete fluorescence emission lines yield rotational temperatures of molecular nitrogen. By empirically choosing multiple rotational levels within the absorption band, non-scanning thermometry can be accurately achieved for molecular nitrogen. It is demonstrated that the N2RIPT technique can measure 1D temperature profile up to ∼5 cm in length within a pure N2environment. Multiple wavelengths are thoroughly analyzed and listed that are accurate for RIPT for various temperature ranges.
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Attosecond electronic dynamics of core-excited states of N2O probed by transient soft X-ray spectroscopy
Half-cycle oscillation is observed in transient absorption spectra of N2O at NKedge (400 eV) irradiated by intense IR pulses, which is attributed to tunneling ionization of core excited states by intensive TDSE-based simulation.
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- Award ID(s):
- 1912507
- PAR ID:
- 10360809
- Date Published:
- Journal Name:
- The International Conference on Ultrafast Phenomena (UP) 2022
- Page Range / eLocation ID:
- W1A.3
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/UP.2022.W1A.3
