Multicomponent Activity Cycles using Hilbert-Huang Analysis

التفاصيل البيبلوغرافية
العنوان: Multicomponent Activity Cycles using Hilbert-Huang Analysis
المؤلفون: Velloso, E. N., Anthony, F., Nascimento Jr, J. D. do, Silveira, L. F. Q., Hall, J., Saar, S. H.
المصدر: The Astrophysical Journal Letters, Volume 945, Issue 1, id.L12, 2023
سنة النشر: 2023
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Solar and Stellar Astrophysics
الوصف: The temporal analysis of stellar activity evolution is usually dominated by a complex trade-off between model complexity and interpretability, often by neglecting the non-stationary nature of the process. Recent studies appear to indicate that the presence of multiple coexisting cycles in a single star is more common than previously thought. The correct identification of physically meaningful cyclic components in spectroscopic time series is therefore a crucial task, which cannot overlook local behaviors. Here we propose a decomposition technique which adaptively recovers amplitude- and frequency-varying components. We present our results for the solar activity as measured both by the sunspot number and the $K$-line emission index, and we consistently recover the Schwabe and Gleissberg cycles as well as the Gnevyshev-Ohl pattern probably related to the Hale cycle. We also recover the known 8-year cycle for 61 Cygni A, in addition to evidence of a three-cycles long pattern reminiscent of the Gnevyshev-Ohl rule. This is particularly interesting as we cannot discard the possibility of a relationship between the measured field polarity reversals and this Hale-like periodicity.
Comment: 8 pages, 3 figures
نوع الوثيقة: Working Paper
DOI: 10.3847/2041-8213/acb8b4
URL الوصول: http://arxiv.org/abs/2310.16974
رقم الأكسشن: edsarx.2310.16974
قاعدة البيانات: arXiv
الوصف
DOI:10.3847/2041-8213/acb8b4