Analysis of optical spectra of V1357 Cyg≡Cyg X-1

Shimanskii, V. V.; Karitskaya, E. A.; Bochkarev, N. G.; Галазутдинов, Г. А.; Lyuty, V. M.; Shimanskaya, N. N.

doi:10.1134/s106377291210006x

Cited by 22 publications

(36 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We note that the BH dimensionless spin recently reported is extremely high, a * > 0.9985 (Miller-Jones et al 2021), which is consistent with the previous measurement, namely a * > 0.983 (Reynolds 2021;Gou et al 2014;Cantiello et al 2014;Orosz et al 2011;Zhao et al 2021). In addition, it has been found that the surface helium-to-hydrogen ratio is about more than a factor of two relative to the solar composition (Shimanskii et al 2012). Therefore, the observations of BH spin measurement and high surface abundance of its companion star has put a challenge for stellar models of massive binary evolution.…”

Section: Introductionsupporting

confidence: 92%

Hypercritical Accretion for Black Hole High Spin in Cygnus X-1

Qin,

Shu,

et al. 2022

Preprint

View full text Add to dashboard Cite

Recent observations of AdLIGO and Virgo have shown that the spin measurements in binary black hole (BH) systems are typically small, which is consistent with the predictions by the classical isolated binary evolution channel. In this standard formation channel, the progenitor of the first-born BH is assumed to have efficient angular momentum transport. The BH spins in high-mass X-ray binaries (HMXBs), however, have been found consistently to be extremely high. In order to explain the high BH spins, the inefficient angular momentum transport inside the BH progenitor is required. This requirement, however, is incompatible with the current understanding of conventional efficient angular momentum transport mechanism. We find that this tension can be highly alleviated as long as the hypercritical accretion is allowed. We show that, for a case study of Cygnus X-1, the hypercritical accretion cannot only be a good solution for the inconsistent assumption upon the angular momentum transport within massive stars, but match its other properties reported recently.

show abstract

Section: Introductionsupporting

confidence: 92%

Hypercritical Accretion for Black Hole High Spin in Cygnus X-1

Qin,

Shu,

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…1. The cross-hatching area marks the stellar chromosphere with the temperature inversion which appears in the case of the "soft" X-ray state (Shimanskii et al, 2012). Fig.…”

Section: Brightness Spots Formation On Cyg X-1 O Supergiantmentioning

confidence: 98%

“…The elements diffusion does not work because of short evolution time and strong macro-turbulence (V macro % 65 AE 7 km/s, Shimanskii et al, 2012). So the magnetic force is the main factor necessary to be taken into account.…”

Section: Magnetic Field Effects On Stellar Atmosphere Structurementioning

confidence: 99%

“…For this purpose, we use the model atmosphere without magnetic field computed by Karitskaya et al (2007) and Shimanskii et al (2012). Fig.…”

Section: Brightness Spots Formation On Cyg X-1 O Supergiantmentioning

confidence: 99%

“…The model atmosphere for the optical component of Cyg X-1 was computed by Karitskaya et al (2005Karitskaya et al ( , 2007 and Shimanskii et al (2012). The X-ray illumination by "soft" and "hard" spectra, tidal distortion of the stellar shape, non-LTE effects were taken into account.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

On possible photometric manifestation of magnetic field in CygX-1

Karitskaya

Bochkarev

2015

Advances in Space Research

View full text Add to dashboard Cite

Element‐abundance inhomogeneity of interstellar matter as it follows from the chemical composition of the O‐type supergiants HDE 226868 (Cyg X‐1) and α Cam

et al. 2013

View full text Add to dashboard Cite

By means of synthetic spectrum modeling with non‐LTE effects, we determined element abundances in the atmospheres of two O supergiants with similar physical characteristics: HDE 226868 (the optical component of Cyg X‐1) and α Cam. These objects are situated at the distance about 2.5 kpc from each other. HDE 226868 has higher abundances compared to α Cam. The differences of Al, S, Zn, and averaged CNO abundances are within 0.15–0.30 dex. This is in a good qualitative agreement with the inhomogeneity of the heavy‐element distribution over the Galactic disk derived by Luck et al. (2006) from Cepheids. This finding confirms the inhomogeneity of chemical‐element distribution on the scale of 2 kpc and is in agreement with the concept of interstellar‐matter superclouds preserving their intrinsic particularities on a time scale in excess of 1 Gyr. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

show abstract

Analysis of optical spectra of V1357 Cyg≡Cyg X-1

Cited by 22 publications

References 33 publications

Hypercritical Accretion for Black Hole High Spin in Cygnus X-1

Hypercritical Accretion for Black Hole High Spin in Cygnus X-1

On possible photometric manifestation of magnetic field in CygX-1

Element‐abundance inhomogeneity of interstellar matter as it follows from the chemical composition of the O‐type supergiants HDE 226868 (Cyg X‐1) and α Cam

Contact Info

Product

Resources

About