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Title: Long term variability of Cygnus X-1: VII. Orbital variability of the focussed wind in Cyg X-1/HDE 226868 system

Abstract

Binary systems with an accreting compact object offer a unique opportunity to investigate the strong, clumpy, line-driven winds of early-type supergiants by using the compact object’s X-rays to probe the wind structure. In this paper, we analyze the two-component wind of HDE 226868, the O9.7Iab giant companion of the black hole Cyg X-1, using 4.77 Ms Rossi X-ray Timing Explorer (RXTE) observations of the system taken over the course of 16 years. Absorption changes strongly over the 5.6 d binary orbit, but also shows a large scatter at a given orbital phase, especially at superior conjunction. The orbital variability is most prominent when the black hole is in the hard X-ray state. Our data are poorer for the intermediate and soft state, but show signs for orbital variability of the absorption column in the intermediate state. We quantitatively compare the data in the hard state to a toy model of a focussed Castor-Abbott-Klein wind: as it does not incorporate clumping, the model does not describe the observations well. Finally, a qualitative comparison to a simplified simulation of clumpy winds with spherical clumps shows good agreement in the distribution of the equivalent hydrogen column density for models with a porosity lengthmore » on the order of the stellar radius at inferior conjunction; we conjecture that the deviations between data and model at superior conjunction could either be due to lack of a focussed wind component in the model or to a more complicated clump structure.« less

Authors:
 [1];  [2];  [3];  [2];  [4];  [5];  [6];  [1];  [7];  [8];  [6]
  1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Kavli Inst. for Astrophysics and Space Research
  2. Univ. of Maryland Baltimore County (UMBC), Baltimore, MD (United States). Center for Research and Exploration in Space Science & Technology (CRESST); NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States). Astrophysics Science Division
  3. Dr. Karl Remeis-Sternwarte – Astronomical Inst. and Erlangen Center for Astroparticle Physics (ECAP), Bamberg (Germany); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  4. Max Planck Inst. for Radio Astronomy, Bonn (Germany); Dr. Karl Remeis-Sternwarte – Astronomical Inst. and Erlangen Center for Astroparticle Physics (ECAP), Bamberg (Germany)
  5. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)
  6. Dr. Karl Remeis-Sternwarte – Astronomical Inst. and Erlangen Center for Astroparticle Physics (ECAP), Bamberg (Germany)
  7. Univ. of Delaware, Newark, DE (United States). Bartol Research Inst.; Ludwig Maximilian Univ., Munich (Germany). Inst. of Astronomy and Astrophysics
  8. Univ. of Wisconsin, Madison, WI (United States). Dept. of Astronomy
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Univ. of Maryland Baltimore County (UMBC), Baltimore, MD (United States); NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); Dr. Karl Remeis-Sternwarte – Astronomical Inst. and Erlangen Center for Astroparticle Physics (ECAP), Bamberg (Germany); Max Planck Inst. for Radio Astronomy, Bonn (Germany)
Sponsoring Org.:
USDOE; National Aeronautic and Space Administration (NASA); Federal Ministry for Economic Affairs and Energy (BMWi) (Germany)
OSTI Identifier:
1438677
Report Number(s):
LLNL-JRNL-741010
Journal ID: ISSN 0004-6361; TRN: US1900483
Grant/Contract Number:  
AC52-07NA27344; SV3-73016; NAS8-03060; NNX12AE37G; NNX12AC72G; 50 OR 1113
Resource Type:
Accepted Manuscript
Journal Name:
Astronomy and Astrophysics
Additional Journal Information:
Journal Volume: 576; Journal ID: ISSN 0004-6361
Publisher:
EDP Sciences
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; stars; Cyg X-1; binary x-rays; winds; outflows

Citation Formats

Grinberg, V., Leutenegger, M. A., Hell, N., Pottschmidt, K., Bock, M., Garcia, J. A., Hanke, M., Nowak, M. A., Sundqvist, J. O., Townsend, R. H. D., and Wilms, J. Long term variability of Cygnus X-1: VII. Orbital variability of the focussed wind in Cyg X-1/HDE 226868 system. United States: N. p., 2015. Web. doi:10.1051/0004-6361/201425418.
Grinberg, V., Leutenegger, M. A., Hell, N., Pottschmidt, K., Bock, M., Garcia, J. A., Hanke, M., Nowak, M. A., Sundqvist, J. O., Townsend, R. H. D., & Wilms, J. Long term variability of Cygnus X-1: VII. Orbital variability of the focussed wind in Cyg X-1/HDE 226868 system. United States. doi:10.1051/0004-6361/201425418.
Grinberg, V., Leutenegger, M. A., Hell, N., Pottschmidt, K., Bock, M., Garcia, J. A., Hanke, M., Nowak, M. A., Sundqvist, J. O., Townsend, R. H. D., and Wilms, J. Thu . "Long term variability of Cygnus X-1: VII. Orbital variability of the focussed wind in Cyg X-1/HDE 226868 system". United States. doi:10.1051/0004-6361/201425418. https://www.osti.gov/servlets/purl/1438677.
@article{osti_1438677,
title = {Long term variability of Cygnus X-1: VII. Orbital variability of the focussed wind in Cyg X-1/HDE 226868 system},
author = {Grinberg, V. and Leutenegger, M. A. and Hell, N. and Pottschmidt, K. and Bock, M. and Garcia, J. A. and Hanke, M. and Nowak, M. A. and Sundqvist, J. O. and Townsend, R. H. D. and Wilms, J.},
abstractNote = {Binary systems with an accreting compact object offer a unique opportunity to investigate the strong, clumpy, line-driven winds of early-type supergiants by using the compact object’s X-rays to probe the wind structure. In this paper, we analyze the two-component wind of HDE 226868, the O9.7Iab giant companion of the black hole Cyg X-1, using 4.77 Ms Rossi X-ray Timing Explorer (RXTE) observations of the system taken over the course of 16 years. Absorption changes strongly over the 5.6 d binary orbit, but also shows a large scatter at a given orbital phase, especially at superior conjunction. The orbital variability is most prominent when the black hole is in the hard X-ray state. Our data are poorer for the intermediate and soft state, but show signs for orbital variability of the absorption column in the intermediate state. We quantitatively compare the data in the hard state to a toy model of a focussed Castor-Abbott-Klein wind: as it does not incorporate clumping, the model does not describe the observations well. Finally, a qualitative comparison to a simplified simulation of clumpy winds with spherical clumps shows good agreement in the distribution of the equivalent hydrogen column density for models with a porosity length on the order of the stellar radius at inferior conjunction; we conjecture that the deviations between data and model at superior conjunction could either be due to lack of a focussed wind component in the model or to a more complicated clump structure.},
doi = {10.1051/0004-6361/201425418},
journal = {Astronomy and Astrophysics},
number = ,
volume = 576,
place = {United States},
year = {2015},
month = {4}
}

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Works referenced in this record:

X-Ray Absorption Events in Cygnus X-1 Observed with Copernicus
journal, September 1974

  • Mason, Keith O.; Hawkins, Frederick J.; Sanford, Peter W.
  • The Astrophysical Journal, Vol. 192
  • DOI: 10.1086/181592

Narrow absorption components and variability in ultraviolet P Cygni profiles of early-type stars
journal, June 1986

  • Prinja, R. K.; Howarth, I. D.
  • The Astrophysical Journal Supplement Series, Vol. 61
  • DOI: 10.1086/191117

In‐Flight Performance of the High Energy X‐Ray Timing Experiment on the Rossi XRay Timing Explorer
journal, March 1998

  • Rothschild, R. E.; Blanco, P. R.; Gruber, D. E.
  • The Astrophysical Journal, Vol. 496, Issue 1
  • DOI: 10.1086/305377

Spectro-timing analysis of Cygnus X-1 during a fast state transition
journal, August 2011


Long term variability of Cygnus X-1: VI. Energy-resolved X-ray variability 1999–2011
journal, April 2014


Long term variability of Cygnus X–1: I. X-ray spectral-temporal correlations in the hard state
journal, September 2003


Constraints on Porosity and mass loss in O-Star Winds from the Modeling of X-Ray Emission line Profile Shapes
journal, May 2013

  • Leutenegger, Maurice A.; Cohen, David H.; Sundqvist, Jon O.
  • The Astrophysical Journal, Vol. 770, Issue 1
  • DOI: 10.1088/0004-637X/770/1/80

Radiation-driven winds in X-ray binaries
journal, October 1982

  • Friend, D. B.; Castor, J. I.
  • The Astrophysical Journal, Vol. 261
  • DOI: 10.1086/160340

Predictions for mass-loss rates and terminal wind velocities of massive O-type stars
journal, January 2012


The distribution of X-ray dips with orbital phase in Cygnus X-1
journal, February 2000

  • Balucinska-Church, M.; Church, M. J.; Charles, P. A.
  • Monthly Notices of the Royal Astronomical Society, Vol. 311, Issue 4
  • DOI: 10.1046/j.1365-8711.2000.03149.x

Long term variability of Cyg X-1: II. The rms-flux relation
journal, January 2004


Constraints on the inclination and masses of the HDE 226868/Cygnus X-1 system from the observations
journal, July 1983

  • Davis, R.; Hartmann, L.
  • The Astrophysical Journal, Vol. 270
  • DOI: 10.1086/161158

X-ray line emission from a fragmented stellar wind
journal, April 2003


Evidence for an about 300 day period in Cygnus X-1
journal, July 1983

  • Priedhorsky, W. C.; Terrell, J.; Holt, S. S.
  • The Astrophysical Journal, Vol. 270
  • DOI: 10.1086/161114

ANS observations of Cygnus X-1
journal, June 1976

  • Parsignault, D. R.; Epstein, A.; Grindlay, J.
  • Astrophysics and Space Science, Vol. 42, Issue 1
  • DOI: 10.1007/BF00645539

A generalized porosity formalism for isotropic and anisotropic effective opacity and its effects on X-ray line attenuation in clumped O star winds: A generalized porosity formalism
journal, December 2011

  • Sundqvist, Jon O.; Owocki, Stanley P.; Cohen, David H.
  • Monthly Notices of the Royal Astronomical Society, Vol. 420, Issue 2
  • DOI: 10.1111/j.1365-2966.2011.20141.x

A Multiwavelength Study of Cygnus x-1: the First Mid-Infrared Spectroscopic Detection of Compact jets
journal, July 2011


Radiation-driven winds in Of stars
journal, January 1975

  • Castor, J. I.; Abbott, D. C.; Klein, R. I.
  • The Astrophysical Journal, Vol. 195
  • DOI: 10.1086/153315

Mass Loss by Hot Stars
journal, January 1970

  • Lucy, L. B.; Solomon, P. M.
  • The Astrophysical Journal, Vol. 159
  • DOI: 10.1086/150365

Long term variability of Cygnus X-1: V. State definitions with all sky monitors
journal, June 2013


The X‐Ray Spectrum and Global Structure of the Stellar Wind in Vela X‐1
journal, November 1999

  • Sako, Masao; Liedahl, Duane A.; Kahn, Steven M.
  • The Astrophysical Journal, Vol. 525, Issue 2
  • DOI: 10.1086/307924

Mass loss from very luminous OB stars and the Cygnus superbubble
journal, November 1981

  • Abbott, D. C.; Bieging, J. H.; Churchwell, E.
  • The Astrophysical Journal, Vol. 250
  • DOI: 10.1086/159412

Orbital, precessional and flaring variability of Cygnus X-1
journal, November 1999


Determination of the masses of the components of the HDE 226868/Cyg X-1 binary system
journal, February 2014

  • Ziółkowski, J.
  • Monthly Notices of the Royal Astronomical Society: Letters, Vol. 440, Issue 1
  • DOI: 10.1093/mnrasl/slu002

Time-dependent models of radiatively driven stellar winds. I - Nonlinear evolution of instabilities for a pure absorption model
journal, December 1988

  • Owocki, Stanley P.; Castor, John I.; Rybicki, George B.
  • The Astrophysical Journal, Vol. 335
  • DOI: 10.1086/166977

Discovery of Two Types of X‐Ray Dips in Cygnus X‐1
journal, January 2002

  • Feng, Y. X.; Cui, Wei
  • The Astrophysical Journal, Vol. 564, Issue 2
  • DOI: 10.1086/324284

On the role of the Accretion disk in Black hole Disk-Jet Connections
journal, August 2012


Broad-band spectra of Cygnus X-1 and correlations between spectral characteristics: Broad-band spectra of Cyg X-1
journal, August 2005


X-ray and ultraviolet spectroscopy of Cygnus X-1 = HDE 226868
journal, April 1980

  • Pravdo, S. H.; White, N. E.; Becker, R. H.
  • The Astrophysical Journal, Vol. 237
  • DOI: 10.1086/183237

CORONA, JET, AND RELATIVISTIC LINE MODELS FOR SUZAKU / RXTE / CHANDRA -HETG OBSERVATIONS OF THE CYGNUS X-1 HARD STATE
journal, January 2011

  • Nowak, Michael A.; Hanke, Manfred; Trowbridge, Sarah N.
  • The Astrophysical Journal, Vol. 728, Issue 1
  • DOI: 10.1088/0004-637X/728/1/13

ADVANCES IN THE RXTE PROPORTIONAL COUNTER ARRAY CALIBRATION: NEARING THE STATISTICAL LIMIT
journal, September 2012


The Spectrum of HDE 226868 (=CYGNUS X-1)
journal, January 1973

  • Walborn, Nolan R.
  • The Astrophysical Journal, Vol. 179
  • DOI: 10.1086/181131

Stellar Wind Variations during the X‐Ray High and Low States of Cygnus X‐11,2
journal, May 2008

  • Gies, D. R.; Bolton, C. T.; Blake, R. M.
  • The Astrophysical Journal, Vol. 678, Issue 2
  • DOI: 10.1086/586690

Clumping in the inner winds of hot, massive stars from hydrodynamical line-driven instability simulations
journal, November 2012

  • Sundqvist, Jon O.; Owocki, Stanley P.
  • Monthly Notices of the Royal Astronomical Society, Vol. 428, Issue 2
  • DOI: 10.1093/mnras/sts165

SAS 3 observations of Cygnus X-1 - The intensity dips
journal, March 1984

  • Remillard, R. A.; Canizares, C. R.
  • The Astrophysical Journal, Vol. 278
  • DOI: 10.1086/161846

Ultraviolet Observations of the X‐Ray Photoionized Wind of Cygnus X‐1 during X‐Ray Soft/High State1
journal, May 2008

  • Vrtilek, S. D.; Boroson, B. S.; Hunacek, A.
  • The Astrophysical Journal, Vol. 678, Issue 2
  • DOI: 10.1086/586692

Comprehensive Analysis of RXTE Data from Cygnus X‐1: Spectral Index–Quasi‐Periodic Oscillation Frequency–Luminosity Correlations
journal, June 2006

  • Shaposhnikov, Nickolai; Titarchuk, Lev
  • The Astrophysical Journal, Vol. 643, Issue 2
  • DOI: 10.1086/503272

Tomographic Analysis of Hα Profiles in HDE 226868/Cygnus X‐1
journal, October 1998

  • Sowers, J. W.; Gies, D. R.; Bagnuolo, Jr., W. G.
  • The Astrophysical Journal, Vol. 506, Issue 1
  • DOI: 10.1086/306246

Pulse Phase‐Resolved Analysis of the High‐Mass X‐Ray Binary Centaurus X‐3 over Two Binary Orbits
journal, March 2008

  • Suchy, Slawomir; Pottschmidt, Katja; Wilms, Jörn
  • The Astrophysical Journal, Vol. 675, Issue 2
  • DOI: 10.1086/527042

Atomic Data for Astrophysics. II. New Analytic FITS for Photoionization Cross Sections of Atoms and Ions
journal, July 1996

  • Verner, D. A.; Ferland, G. J.; Korista, K. T.
  • The Astrophysical Journal, Vol. 465
  • DOI: 10.1086/177435

A DETAILED X-RAY INVESTIGATION OF ζ Puppis. II. THE VARIABILITY ON SHORT AND LONG TIMESCALES
journal, January 2013


Clumped stellar winds in supergiant high-mass X-ray binaries: X-ray variability and photoionization: Clumped stellar winds in HMXBs
journal, March 2012


Long term variability of Cygnus X-1: IV. Spectral evolution 1999–2004
journal, January 2006


CHANDRA X-RAY SPECTROSCOPY OF THE FOCUSED WIND IN THE CYGNUS X-1 SYSTEM. I. THE NONDIP SPECTRUM IN THE LOW/HARD STATE
journal, December 2008


The mass of the Black hole in Cygnus x-1
journal, November 2011

  • Orosz, Jerome A.; McClintock, Jeffrey E.; Aufdenberg, Jason P.
  • The Astrophysical Journal, Vol. 742, Issue 2
  • DOI: 10.1088/0004-637X/742/2/84

The Effect of Porosity on X‐Ray Emission‐Line Profiles from Hot‐Star Winds
journal, September 2006

  • Owocki, Stanley P.; Cohen, David H.
  • The Astrophysical Journal, Vol. 648, Issue 1
  • DOI: 10.1086/505698

The Trigonometric Parallax of Cygnus x-1
journal, November 2011

  • Reid, Mark J.; McClintock, Jeffrey E.; Narayan, Ramesh
  • The Astrophysical Journal, Vol. 742, Issue 2
  • DOI: 10.1088/0004-637X/742/2/83

Two-dimensional simulations of the line-driven instability in hot-star winds
journal, July 2003


The Treatment of Non‐LTE Line Blanketing in Spherically Expanding Outflows
journal, March 1998

  • Hillier, D. John; Miller, D. L.
  • The Astrophysical Journal, Vol. 496, Issue 1
  • DOI: 10.1086/305350

Revealing the Focused Companion Wind in Cygnus X‐1 with Chandra
journal, February 2005

  • Miller, J. M.; Wojdowski, P.; Schulz, N. S.
  • The Astrophysical Journal, Vol. 620, Issue 1
  • DOI: 10.1086/426701

Superorbital variability of X-ray and radio emission of Cyg X-1 – I. Emission anisotropy of precessing sources
journal, September 2007

  • Ibragimov, Askar; Zdziarski, Andrzej A.; Poutanen, Juri
  • Monthly Notices of the Royal Astronomical Society, Vol. 381, Issue 2
  • DOI: 10.1111/j.1365-2966.2007.12222.x

The Cessation of Flickering during Dips in Cygnus X-1
journal, May 1997

  • BaŁuciŃska-Church, M.; Takahashi, T.; Ueda, Y.
  • The Astrophysical Journal, Vol. 480, Issue 2
  • DOI: 10.1086/310633

The doubling of the superorbital period of Cyg X-1: The doubling of the SO period of Cyg X-1
journal, January 2011

  • Zdziarski, Andrzej A.; Pooley, Guy G.; Skinner, Gerald K.
  • Monthly Notices of the Royal Astronomical Society, Vol. 412, Issue 3
  • DOI: 10.1111/j.1365-2966.2010.18034.x

Beyond XSPEC: Toward Highly Configurable Astrophysical Analysis
journal, July 2008

  • Noble, M. S.; Nowak, M. A.
  • Publications of the Astronomical Society of the Pacific, Vol. 120, Issue 869
  • DOI: 10.1086/590324

ISMabs: A COMPREHENSIVE X-RAY ABSORPTION MODEL FOR THE INTERSTELLAR MEDIUM
journal, February 2015


Wind Accretion and State Transitions in Cygnus X‐1
journal, January 2003

  • Gies, D. R.; Bolton, C. T.; Thomson, J. R.
  • The Astrophysical Journal, Vol. 583, Issue 1
  • DOI: 10.1086/345345

HIGHLY IONIZED Fe-K ABSORPTION LINE FROM CYGNUS X-1 IN THE HIGH/SOFT STATE OBSERVED WITH SUZAKU
journal, April 2013


X-Ray Variations at the Orbital Period from Cygnus x-1 in the High/Soft State
journal, January 2010


The Interaction of X-Ray Sources with Optically Thin Environments
journal, June 1969

  • Tarter, C. Bruce; Tucker, Wallace H.; Salpeter, Edwin E.
  • The Astrophysical Journal, Vol. 156
  • DOI: 10.1086/150026

X-ray emission lines from inhomogeneous stellar winds
journal, July 2004


The shadow wind in high-mass X-ray binaries
journal, November 1994

  • Blondin, John M.
  • The Astrophysical Journal, Vol. 435
  • DOI: 10.1086/174853

Long term variability of Cygnus X-1: III. Radio–X-ray correlations
journal, September 2004


Low charge states of Si and S in Cygnus X-1
journal, September 2013


The Optical Spectrum of HDE 226868=Cygnus X-1. III. A Focused Stellar Wind Model for He II lambda 4686 Emission
journal, May 1986

  • Gies, D. R.; Bolton, C. T.
  • The Astrophysical Journal, Vol. 304
  • DOI: 10.1086/164172

First Results from the All-Sky Monitor on the [ITAL]Rossi X-Ray Timing Explorer[/ITAL]
journal, September 1996

  • Levine, Alan M.; Bradt, Hale; Cui, Wei
  • The Astrophysical Journal, Vol. 469, Issue 1
  • DOI: 10.1086/310260

The optical spectrum of HDE 226868 = Cygnus X-1. II - Spectrophotometry and mass estimates
journal, May 1986

  • Gies, D. R.; Bolton, C. T.
  • The Astrophysical Journal, Vol. 304
  • DOI: 10.1086/164171

Simultaneous X-ray and optical observations of GX 339-4 in an X-ray high state
journal, September 1986

  • Makishima, K.; Maejima, Y.; Mitsuda, K.
  • The Astrophysical Journal, Vol. 308
  • DOI: 10.1086/164534

Calibration of the Rossi X‐Ray Timing Explorer Proportional Counter Array
journal, April 2006

  • Jahoda, Keith; Markwardt, Craig B.; Radeva, Yana
  • The Astrophysical Journal Supplement Series, Vol. 163, Issue 2
  • DOI: 10.1086/500659

Observation of an absorption dip in the X-ray intensity CYG X-1.
journal, July 1974

  • Li, K. F.; Clark, G. W.
  • The Astrophysical Journal, Vol. 191
  • DOI: 10.1086/181538

Superorbital variability of X-ray and radio emission of Cyg X-1 - II. Dependence of the orbital modulation and spectral hardness on the superorbital phase
journal, September 2008

  • Poutanen, Juri; Zdziarski, Andrzej A.; Ibragimov, Askar
  • Monthly Notices of the Royal Astronomical Society, Vol. 389, Issue 3
  • DOI: 10.1111/j.1365-2966.2008.13666.x

On the Absorption of X‐Rays in the Interstellar Medium
journal, October 2000

  • Wilms, J.; Allen, A.; McCray, R.
  • The Astrophysical Journal, Vol. 542, Issue 2
  • DOI: 10.1086/317016

Probing the temporal variability of Cygnus X-1 into the soft state
journal, June 2006


Using the X-Ray dust Scattering halo of Cygnus x-1 to Determine Distance and dust Distributions
journal, August 2011


The Discordance of Mass‐Loss Estimates for Galactic O‐Type Stars
journal, February 2006

  • Fullerton, A. W.; Massa, D. L.; Prinja, R. K.
  • The Astrophysical Journal, Vol. 637, Issue 2
  • DOI: 10.1086/498560

Mass Loss from Three OB Supergiants in Orion
journal, November 1967

  • Morton, Donald C.
  • The Astrophysical Journal, Vol. 150
  • DOI: 10.1086/149356