Nigul Olspert

Research outputs

  1. 2019
  2. E-pub ahead of print
  3. 2018
  4. Published

    Transition from axi- to nonaxisymmetric dynamo modes in spherical convection models of solar-like stars

    Viviani, M., Warnecke, J., Käpylä, M. J., Käpylä, P. J., Olspert, N., Cole-Kodikara, E. M., Lehtinen, J. J. & Brandenburg, A., 1 Aug 2018, In : Astronomy and Astrophysics. 616, p. 1-19 A160.

    Research output: Contribution to journalArticleScientificpeer-review

  5. Published

    Estimating activity cycles with probabilistic methods I. Bayesian Generalised Lomb-Scargle Periodogram with Trend

    Olspert, N., Pelt, J., Käpylä, M. J. & Lehtinen, J. J., Jul 2018, In : Astronomy and Astrophysics. 615, p. 1-13 A111.

    Research output: Contribution to journalArticleScientificpeer-review

  6. Published

    Estimating activity cycles with probabilistic methods II: The Mount Wilson Ca H&K data

    Olspert, N., Lehtinen, J. J., Käpylä, M. J., Pelt, J. & Grigorievskiy, A., 2018, In : Astronomy and Astrophysics. 619, p. 1-20 A6.

    Research output: Contribution to journalArticleScientificpeer-review

  7. Published

    From periodic to cyclic processes in stellar magnetic activity research: time series analysis methods and their applications

    Olspert, N., 2018, Aalto University. 240 p.

    Research output: ThesisDoctoral ThesisCollection of Articles

  8. 2017
  9. Published

    Extended Subadiabatic Layer in Simulations of Overshooting Convection

    Käpylä, P. J., Rheinhardt, M., Brandenburg, A., Arlt, R., Käpylä, M. J., Lagg, A., Olspert, N. & Warnecke, J., 20 Aug 2017, In : Astrophysical Journal Letters. 845, 2, p. 1-6 L23.

    Research output: Contribution to journalArticleScientificpeer-review

  10. Published

    Method of frequency dependent correlations: Investigating the variability of total solar irradiance

    Pelt, J., Käpylä, M. & Olspert, N., 1 Apr 2017, In : Astronomy and Astrophysics. 600, p. 1-19 A9.

    Research output: Contribution to journalArticleScientificpeer-review

  11. Published

    Method for estimating cycle lengths from multidimensional time series: Test cases and application to a massive 'in silico' dataset

    Olspert, N., Kapyla, M. J. & Pelt, J., 2 Feb 2017, Proceedings - 2016 IEEE International Conference on Big Data, Big Data 2016. Institute of Electrical and Electronics Engineers, p. 3214-3223 10 p. 7840977

    Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

  12. Published

    Convection-driven spherical shell dynamos at varying Prandtl numbers

    Käpylä, P. J., Käpylä, M. J., Olspert, N., Warnecke, J. & Brandenburg, A., 2017, In : Astronomy and Astrophysics. 599, 18 p., A4.

    Research output: Contribution to journalArticleScientificpeer-review

  13. 2016
  14. Published

    Multiple dynamo modes as a mechanism for long-term solar activity variations

    Käpylä, M., Käpylä, P., Olspert, N., Brandenburg, A., Warnecke, J., Karak, B. B. & Pelt, J., May 2016, In : Astronomy and Astrophysics. 589, 24 p., 56.

    Research output: Contribution to journalArticleScientificpeer-review

  15. 2015
  16. Published

    Magnetically controlled stellar differential rotation near the transition from solar to anti-solar profiles

    Karak, B. B., Käpylä, P. J., Käpylä, M. J., Brandenburg, A., Olspert, N. & Pelt, J., 2015, In : Astronomy and Astrophysics. 576, 17 p., A26.

    Research output: Contribution to journalArticleScientificpeer-review

  17. Published

    Multiperiodicity, modulations, and flip-flops in variable star light curves - III.Carrier fit analysis of LQ Hydrae photometry for 19822014

    Olspert, N., Käpylä, M. J., Pelt, J., Cole, E. M., Hackman, T., Lehtinen, J. & Henry, G. W., 2015, In : Astronomy and Astrophysics. 577, 13 p., A120.

    Research output: Contribution to journalArticleScientificpeer-review

  18. Published

    Statistical Study of Strong and Extreme Geomagnetic Disturbances and Solar Cycle Characteristics

    Kilpua, E. K. J., Olspert, N., Grigorevskiy, A., Käpylä, M., Tanskanen, E. I., Miyahara, H., Kataoka, R., Pelt, J. & Liu, Y. D., 2015, In : Astrophysical Journal. 806, 2, p. 272

    Research output: Contribution to journalArticleScientificpeer-review

  19. 2013
  20. Published

    Multiperiodicity, modulations and flip-flops in variable star light curves: II. Analysis of II Pegasus photometry during 1979-2010

    Lindborg, M., Mantere, M. J., Olspert, N., Pelt, J., Hackman, T., Henry, G. W., Jetsu, L. & Strassmeier, K. G., 2013, In : Astronomy and Astrophysics. 559, p. 1-10 A97.

    Research output: Contribution to journalArticleScientificpeer-review

  21. 2011
  22. Published

    Multiperiodicity, modulations and flip-flops in variable star light curves: I. Carrier fit method

    Pelt, J., Olspert, N., Mantere, M. J. & Tuominen, I., 2011, In : Astronomy and Astrophysics. 535, p. 1-12 A23.

    Research output: Contribution to journalArticleScientificpeer-review

  23. Published

    Towards the automatic estimation of time delays of gravitational lenses

    Hirv, A., Olspert, N. & Pelt, J., 2011, In : Baltic Astronomy. 20, 2, p. 125-144 20 p.

    Research output: Contribution to journalArticleScientificpeer-review

ID: 85006