Vol. 37, issue 09, article # 12

Abstract:

The study of the spatiotemporal structure of optical turbulence and the development of methods for determining its characteristics at different altitudes in the atmosphere are of great importance for astronomical adaptive optics. Design of an adaptive optics system and technical characteristics of its components largely depend on optical turbulence along the line of sight a telescope. In this paper, the method for estimation of vertical profiles of the air refractive index structure characteristic is modified. Based on the ERA5 reanalysis data, this method was used to derive statistically representative vertical profiles of the air refractive index structure characteristic and the outer scale of turbulence at the Large Solar Vacuum Telescope (LSVT) site. The problem of estimating the turbulence outer scale is discussed taking into account surface mast micrometeorolo­gical measurements and optical measurements at the LSVT. The results are the basis for constructing a multi-mirror adaptive optics system for the LSVT. In particular, these profiles are important for further refinement of the optical conjugation heights. The suggested method can also be used to describe optical turbulence over other ground-based solar telescopes.

Keywords:

astroclimate, atmosphere, turbulence, outer scale of turbulence

References:

1. Bi C., Qing C., Qian X., Zhu W., Luo T., Li X., Cui S., Weng N. Astroclimatic parameters characterization at lenghu site with ERA5 products // Mon. Not. R. Astron. Soc. 2024. V. 527. P. 4616–4631. DOI: 10.1093/mnras/stad3414.
2. Bol'basova L.A., Lukin V.P. Analiticheskie modeli vysotnoi zavisimosti strukturnoi postoyannoi pokazatelya prelomleniya turbulentnoi atmosfery dlya zadach adaptivnoi optiki // Optika atmosf. i okeana. 2016. V. 29, N 11. P. 918–925. DOI: 10.15372/AOO20161104.
3. Langlois M., Moretto G., Richards K., Hegwer S., Rimmele T. Solar multi-conjugate adaptive optics at the Dunn Solar Telescope: Preliminary results // Proc. SPIE. 2004. V. 5490. DOI: 10.1051/ao4elt/201008002.
4. Schmidt D., Gorceix N., Goode P.R., Marino J., Rimmele T., Wöger F., Zhang X., Rigaut F., von der Lühe O. Clear widens the field for observations of the Sun with multi-conjugate adaptive optics // Astron. Astrophys. 2017. V. 597. L8. DOI: 10.1051/0004-6361/201629970.
5. Zhong L., Zhang L., Shi Z., Tian Y., Guo Y., Kong L., Rao X., Bao H., Zhu L., Rao C. Wide field-of-view, high-resolution solar observation in combination with ground layer adaptive optics and speckle imaging // Astron. Astrophys. 2020. V. 637. A99. DOI: 10.1051/0004-6361/201935109.
6. Schmidt D., Berkefeld T., Heidecke F., von der Lühe O., Soltau D. Testbed for the multi-conjugate adaptive optics system of the Solar Telescope GREGOR // Proc. SPIE. 2009. V. 74390X. DOI: 10.1117/12.829886.
7. Butterley T., Wilson R., Sarazin M. Determination of the profile of atmospheric optical turbulence strength from SLODAR data // Mon. Not. R. Astron. Soc. 2006. V. 369, N 2. P. 835–845. DOI: 10.1111/j.1365-2966.2006.10337.x.
8. Goodwin M., Jenkins C., Lambert A. Improved detection of atmospheric turbulence with SLODAR // Opt. Express. 2007. V. 15, N 22. P. 14844–14860. DOI: 10.1364/OE.15.014844.
9. Wilson R.W. SLODAR: Measuring optical turbulence altitude with a Shack–Hartmann wavefront sensor // Mon. Not. R. Astron. Soc. 2002. V. 337, N 1. P. 103–108. DOI: 10.1046/j.1365-8711.2002.05847.x.
10. Osborn J., Butterley T., Föhring D., Wilson R. Characterising atmospheric optical turbulence using stereo-SCIDAR // J. Phys.: Conf. Ser. 2015. V. 595. DOI: 10.1088/1742-6596/595/1/012022.
11. Potanin S.A., Kornilov M.V., Savvin A.D., Safonov B.S., Ibragimov M.A., Kopylov E.A., Nalivkin M.A., Shmagin V.E., Huy L.X., Thao N.T. A Facility for the study of atmospheric parameters based on the Shack–Hartmann Sensor // Astrophys. Bull. 2022. V. 77, N 2. P. 214–221. DOI: 10.1134/S1990341322020067.
12. Wang Z., Zhang L., Kong L., Bao H., Guo Y., Rao X., Zhong L., Zhu L., Rao C. A modified S-DIMM+: Applying additional height grids for characterizing daytime seeing profiles // Mon. Not. R. Astron. Soc. 2018. V. 478, N 2. P. 1459–1467.
13. Shikhovtsev A.Yu., Kiselev A.V., Kovadlo P.G., Kolobov D.Yu., Lukin V.P., Tomin V.E. Metod opredeleniya vysot turbulentnykh sloev v atmosfere // Optika atmosf. i okeana. 2019. V. 32, N 12. P. 994–1000. DOI: 10.15372/AOO20191208; Shikhovtsev A.Y., Kiselev A.V., Kovadlo P.G., Kolobov D.Yu., Tomin V.E., Lukin V.P. Method for estimating the altitudes of atmospheric layers with strong turbulence // Atmos. Ocean. Opt. 2020. V. 33, N 3. P. 295–301.
14. Shikhovtsev A.Y., Kovadlo P.G., Kiselev A.V., Kolobov D.Y., Lukin V.P., Russkikh I.V., Shikhovtsev M.Y. Modified method to detect the turbulent layers in the atmospheric boundary layer for the Large Solar Vacuum Telescope // Atmosphere. 2021. V. 12. P. 159. DOI: 10.3390/atmos12020159.
15. Tatarskii V.I. Rasprostranenie voln v turbulentnoi atmosfere. M.: Nauka, 1967. 548 p.
16. Maire J., Ziad A., Borgnino J., Martin F. Measurements of profiles of the wavefront outer scale using observations of the limb of the Moon // Mon. Not. R. Astron. Soc. 2007. V. 377. P. 1236–1244. DOI: 10.1111/j.1365-2966.2007.11681.x.
17. Dewan E., Good R., Beland R., Brown J. A Model C_n² (Optical Turbulence) Profiles Using Radiosonde Data  MA: Phillips Laboratory, 1993. N 1121.
18. van de Boer A., Moene A.F., Graf A., Simmer C., Holtslag A.A.M. Estimation of the refractive index structure parameter from single-level daytime routine weather data // Appl. Opt. 2014. V. 53. P. 5944–5960. DOI: 10.1364/AO.53.005944.
19. Wang S., Wang Q., Wauer B.J., Jiang Q. Computing refractive index structure parameter C_n² in a numerical weather prediction model // Geophys. Res. Lett. 2020. V. 47, N 17. DOI: 10.1029/2020GL089168.
20. Shikhovtsev A., Kovadlo P., Lukin V. Temporal variations of the turbulence profiles at the sayan solar observatory site // Atmosphere. 2019. V. 10, N 9. P. 499. DOI: 10.3390/atmos10090499.
21. Botygina N.N., Emaleev O.N., Konyaev P.A., Kopylov E.A., Lukin V.P. Development of elements for an adaptive optics system for solar telescope // J. Appl. Remote Sens. 2018. V. 12, N 4. P. 042403. DOI: 10.1117/1.JRS.12.042403.
22. Antoshkin L.V., Botygina N.N., Bolbasova L.A., Emaleev O.N., Konyaev P.A., Kopylov E.A., Kovadlo P.G., Kolobov D.Yu., Kudryashov A.V., Lavrinov V.V., Lavrinova L.N., Lukin V.P., Chuprakov S.A., Selin A.A., Shikhovtsev A.Yu. Adaptivnaya opticheskaya sistema dlya solnechnogo teleskopa, obespechivayushchaya ego rabotosposobnost' v usloviyakh sil'noi atmosfernoi turbulentnosti // Optika atmosf. i okeana. 2016. V. 29, N 11. P. 895–904. DOI: 10.15372/AOO20161101; Antoshkin L.V., Botygina N.N., Bolbasova L.A., Emaleev O.N., Konyaev P.A., Kopylov E.A., Kovadlo P.G., Kolobov D.Yu., Kudryashov A.V., Lavrinov V.V., Lavrinova L.N., Lukin V.P., Chuprakov S.A., Selin A.A., Shikhovtsev A.Yu. Adaptive optics system for solar telescope operating under strong atmospheric turbulence // Atmos. Ocean. Opt. 2017. V. 30, N 3. P. 291–299.
23. Abahamid A., Vernin J., Benkhaldoun Z., Jabiri A., Azouit M., Agabi A. Seeing, outer scale of optical turbulence, and coherence outer scale at different astronomical sites using instruments on meteorological balloons // Astron. Astrophys. 2004. V. 422. P. 1123–1127. DOI: 10.1051/0004-6361:20040215.
24. Lukin V.P. Vneshnii masshtab turbulentnosti i ego vliyanie na fluktuatsii opticheskikh voln // Uspekhi fiz. nauk. 2021. V. 191, N 3. P. 292–317. DOI: 10.3367/UFNr.2020.10.038849.
25. Koshkarov A.S., Mal'tsev G.N. Issledovanie uslovii anizoplanatizma nazemnykh opticheskikh sistem s ispol'zovaniem modelei atmosfery // Trudy Voenno-kosmicheskoi akademii im. A.F. Mozhaiskogo. 2023. V. 689. P. 52–59.
26. Molozhnikova Y.V., Shikhovtsev M.Y., Netsvetaeva O.G., Khodzher T.V. Ecological zoning of the Baikal basin based on the results of chemical analysis of the composition of atmospheric precipitation accumulated in the snow cover // Appl. Sci. 2023, V. 13. DOI: 10.3390/app13148171.