Akademska digitalna zbirka SLovenije - logo
E-viri
Celotno besedilo
Odprti dostop
  • Stoyanov, K A; Luna, G J M; Zamanov, R K; Ilkiewicz, K; Nikolov, Y M; Moyseev, M; Minev, M; Kurtenkov, A; Stefanov, S Y

    arXiv.org, 06/2024
    Paper, Journal Article

    T CrB is a symbiotic star that experiences nova outbursts every \(\sim\) 80~yr. The next, long-anticipated nova outburst should occur during the 2024-2026 period. Here, we present results of high-resolution optical spectroscopy of T CrB in the period 2016 - 2023. In these spectra, we measured the equivalent widths of the H\(\alpha\), H\(\beta\), HeI and HeII emission lines. The maximum equivalent width (EW) was recorded on May 2021, when the EW of \(H\alpha\) reached -44.6 \AA and H\(\beta\) = -21.5 \AA. At the other extreme, the minimum of EW(\(H\alpha\))= -2.9 \AA was recorded in October 2023. After October 2023, the B-band emission brightened, suggesting a re-appearance of the orbital modulation. In addition to the optical data, we study the X-ray behaviour in the same period. We find a strong correlation between \(EW(H\alpha)\) and X-ray flux with a correlation coefficient -0.78 and a significance of 2.6\(\times 10^{-5}\).