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ARF Bot

{
  "id": "cli07qqnv00c9sa0g8njd4w3l-991aaa9081505b7fb822b42cc486a3a2",
  "text": "R.V. Kochanov, Y. Tan, P.F. Bernath, M. Birk, V. Boudon, A. Campargue, K.V. Chance, B.J. Drouin, J.-M. Flaud, R.R. Gamache, J.T. Hodges, D. Jacquemart, V.I. Perevalov, A. Perrin, K.P. Shine, M.-A.H. Smith, J. Tennyson, G.C. Toon, H. Tran, V.G. Tyuterev, A. Barbe, A.G. Császár, V.M. Devi, T. Furtenbacher, J.J. Harrison, J.-M. Hartmann, A. Jolly, T.J. Johnson, T. Karman, I. Kleiner, A.A. Kyuberis, J. Loos, O.M. Lyulin, S.T. Massie, S.N. Mikhailenko, N. Moazzen-Ahmadi, H.S.P. Müller, O.V. Naumenko, A.V. Nikitin, O.L. Polyansky, M. Rey, M. Rotger, S.W. Sharpe, K. Sung, E. Starikova, S.A. Tashkun, J. Vander Auwera, G. Wagner, J. Wilzewski, P. Wcisło, S. Yu, E.J. Zak, \"The HITRAN2016 molecular spectroscopic database,\" Journal of Quantitative Spectroscopy and Radiative Transfer 203, 3-69 (2017)]. By changing the laser temperature we could accessed several of these transitions, as shown in Fig. 3b. Absorption line near 4991.2 cm"
}

{
  "id": "cli07qqnv00c9sa0g8njd4w3l-d10f2409fd8f519f823a3c2a59ea9b9a",
  "text": "higher order modes are strongly attenuated. As a result, as shown in this work but also in [refs] where Kagome-type fiber was used, optical fringes visible in spectroscopic setups with AR-HCFs may have much lower amplitudes. However, their amplitude strongly depends on coupling into the HCF. Figure 6 shows two 2f WMS spectra recorded within less than one minute. Between the two measurements we have slightly realigned fiber from the laser diode. It is clear that one spectral scan (dashed line) contains fringes with much larger amplitude comparing to the other (solid line). Interestingly, in both cases total power reaching the detector was very similar. Therefore, it must be concluded that aligning the system to maximize the coupling efficiency and power on the detector only does not guarantee that spectrum with no fringes will be obtained. It is also worth noticing that when the setup was left for one or two days optical fringes similar to shown in Fig. 6 with dashed line were present. With small realignment these unwanted features could be removed and the setup stayed stable for few hours.\n\nFigure 6.\n\nConclusions\n\nIn this paper a very simple laser-based spectrometer at 2 µm using anti-resonant hollow core fiber was presented. A minimum detection limit of 5 ppmv of CO2 (which corresponds to minimum detectable fractional absorption of 110-4) and gas exchange rate as low as 5 seconds were obtained. This was achieved using 1.35-m-long fiber and a very simple optical configuration (without any mirrors or lenses in the setup). This outperforms not only previously demonstrated examples of absorption-based spectroscopy with PBG-type HCFs [refs] but also recently published results obtained using Kagome-type HCFs [refs]. Thanks to relatively low losses of AR-HCFs presented performance gives perspective for simple and highly compact fiber-based spectrom"
}

{
  "id": "cli07qqnv00c9sa0g8njd4w3l-7c251830ce925fa8afcf2127cf83e064",
  "text": "type HCFs [refs] but also recently published results obtained using Kagome-type HCFs [refs]. Thanks to relatively low losses of AR-HCFs presented performance gives perspective for simple and highly compact fiber-based spectrometers with long optical path-lengths.\n\nAcknowledgements\n\nThis work has been carried out in scope of the project Narodowe Centrum Nauki (NCN) OPUS grant (UMO-2016/21/B/ST7/02249) and First TEAM programme of the Foundation for Polish Science co-financed by the European Union under the European Regional Development Fund (project number First TEAM/2016-1/1)."
}