Intensity interferometry of P Cygni in the H$\alpha$ emission line: towards distance calibration of LBV supergiant stars

Abstract

We present intensity interferometry of the luminous blue variable P Cyg in the light of its H$\alpha$ emission performed with 1\,m-class telescopes. We compare the measured visibility points to synthesized interferometric data based on the CMFGEN physical modeling of a high-resolution spectrum of P Cyg recorded almost simultaneously with our interferometry data. Tuning the stellar parameters of P Cyg and its H$\alpha$ linear diameter we estimate the distance of P Cyg as $1.56\pm 0.25$~kpc, which is compatible within $1\sigma$ with $1.36\pm 0.24$~kpc reported by the Gaia DR2 catalogue of parallaxes recently published. Both values are significantly smaller than the canonic value of $1.80\pm 0.10$~kpc usually adopted in literature. Our method used to calibrate the distance of P Cyg can apply to very massive and luminous stars both in our galaxy and neighbour galaxies and can improve the so-called Wind-Momentum Luminosity relation that potentially applies to calibrate cosmological candles in the local Universe.

arXiv commentTo be published in MNRAS

References in corpus (25)

• Gaia Data Release 2. Summary of the contents and survey properties
• A Grid of NLTE Line-Blanketed Model Atmospheres of Early B-type Stars
• PIONIER: a 4-telescope visitor instrument at VLTI
• O stars with weak winds: the Galactic case
• Properties of Galactic early-type O-supergiants: A combined FUV-UV and optical analysis
• Analysis of Galactic late-type O dwarfs: more constraints on the weak wind problem
• Near-Infrared interferometry of Eta Carinae with high spatial and spectral resolution using the VLTI and the AMBER instrument
• Models of interacting supernovae and their spectral diversity
• On the influence of the companion star in Eta Carinae: 2D radiative transfer modeling of the ultraviolet and optical spectra
• Temporal intensity interferometry: photon bunching on three bright stars
• The first X-ray survey of Galactic Luminous Blue Variables
• X-ray emission from massive stars in Cyg OB2
• Detailed Far-UV to Optical Analysis of Four [WR] Stars
• Optical intensity interferometry observations using the MAGIC imaging atmospheric Cherenkov telescopes
• Spatial intensity interferometry on three bright stars
• Asymptotic Giant Branch Variables in the Galaxy and the Local Group
• On the nature of WO stars: a quantitative analysis of the WO3 star DR1 in IC 1613
• Characterization of very narrow spectral lines with temporal intensity interferometry
• Probing the weak wind phenomenon in Galactic O-type giants
• Adaptive optics imaging of P Cygni in Halpha
• Optical long baseline intensity interferometry: prospects for stellar physics
• The H-band Emitting Region of the Luminous Blue Variable P Cygni: Spectrophotometry and Interferometry of the Wind
• The Spatially Resolved Hα-Emitting Wind Structure of P Cygni
• The H-alpha Variations of the Luminous Blue Variable P Cygni: Discrete Absorption Components and the Short S Doradus Phase
• Science opportunities enabled by the era of Visible Band Stellar Imaging with sub-100 μarc-sec angular resolution

Cited by in corpus (17)

• Demonstration of stellar intensity interferometry with the four VERITAS telescopes
• ASTRI Mini-Array Core Science at the Observatorio del Teide
• A quantitative comparison of amplitude versus intensity interferometry for astronomy
• Radiation-Driven Wind Hydrodynamics of Massive Stars: A Review
• A Panchromatic Study of Massive Stars in the Extremely Metal-Poor Local Group Dwarf Galaxy Leo A
• Stellar intensity interferometry of Vega in photon counting mode
• Combined spectroscopy and intensity interferometry to determine the distances of the blue supergiants P Cygni and Rigel
• Observations with the Southern Connecticut Stellar Interferometer. I. Instrument Description and First Results
• I3T: Intensity Interferometry Imaging Telescope
• Intensity Interferometry observations of the H$\alpha$ envelope of $\gamma$ Cas with MéO and a portable telescope
• Field and intensity correlations: the Siegert relation from stars to quantum emitters
• Comparing Different Approaches for Stellar Intensity Interferometry
• Photon counting intensity interferometry in the blue at a 0.5 m telescope
• Unveiling the evolutionary state of three B supergiant stars: PU Gem, $\epsilon$ CMa and $\eta$ CMa
• Investigating the accuracy achievable in reconstructing the angular sizes of stars through stellar intensity interferometry observations
• Stellar intensity interferometry in the photon-counting regime
• Radius measurement in binary stars: simulations of intensity interferometry