The independency of stellar mass-loss rates on stellar X-ray luminosity and activity level based on solar X-ray flux and solar wind observations

AbstractMassive stars lose a considerable amount of mass during their lifetime. When the star explodes as a supernova (SN), the resulting shock wave expands in the medium created by the stellar mass-loss. Thermal X-ray emission from the SN depends on the square of the density of the ambient medium, which in turn depends on the mass-loss rate (and velocity) of the progenitor wind. The emission can therefore be used to probe the stellar mass-loss in the decades or centuries before the star’s death.We have aggregated together data available in the literature, or analysed by us, to compute the X-ray lightcurves of almost all young supernovae detectable in X-rays. We use this database to explore the mass-loss rates of massive stars that collapse to form supernovae. Mass-loss rates are lowest for the common Type IIP supernovae, but increase by several orders of magnitude for the highest luminosity X-ray SNe.

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Measuring mass-loss rates and constraining shock physics using X-ray line profiles of O stars from the Chandra archive

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stu008 ◽

2014 ◽

Vol 439 (1) ◽

pp. 908-923 ◽

Cited By ~ 48

Author(s):

David H. Cohen ◽

Emma E. Wollman ◽

Maurice A. Leutenegger ◽

Jon O. Sundqvist ◽

Alex W. Fullerton ◽

...

Keyword(s):

Mass Loss ◽

Line Profiles ◽

Shock Physics ◽

X Ray ◽

Loss Rates

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What Do We Really Know About the Winds of Massive Stars?

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308020371 ◽

2007 ◽

Vol 3 (S250) ◽

pp. 89-96

Author(s):

D. John Hillier

Keyword(s):

Mass Loss ◽

Massive Stars ◽

Standard Theory ◽

Stellar Winds ◽

X Rays ◽

X Ray ◽

Stellar Photosphere ◽

Weak Winds ◽

Ionization Balance ◽

Loss Rates

AbstractThe standard theory of radiation driven winds has provided a useful framework to understand stellar winds arising from massive stars (O stars, Wolf-Rayet stars, and luminous blue variables). However, with new diagnostics, and advances in spectral modeling, deficiencies in our understanding of stellar winds have been thrust to the forefront of our research efforts. Spectroscopic observations and analyses have shown the importance of inhomogeneities in stellar winds, and revealed that there are fundamental discrepancies between predicted and theoretical mass-loss rates. For late O stars, spectroscopic analyses derive mass-loss rates significantly lower than predicted. For all O stars, observed X-ray fluxes are difficult to reproduce using standard shock theory, while observed X-ray profiles indicate lower mass-loss rates, the potential importance of porosity effects, and an origin surprisingly close to the stellar photosphere. In O stars with weak winds, X-rays play a crucial role in determining the ionization balance, and must be taken into account.

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Radiation-hydrodynamical models of X-ray photoevaporation in carbon-depleted circumstellar discs

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2939 ◽

2019 ◽

Vol 490 (4) ◽

pp. 5596-5614 ◽

Cited By ~ 2

Author(s):

Lisa Wölfer ◽

Giovanni Picogna ◽

Barbara Ercolano ◽

Ewine F van Dishoeck

Keyword(s):

Mass Loss ◽

Gas Phase ◽

Central Star ◽

X Rays ◽

Hydrodynamical Models ◽

X Ray ◽

Energetic Radiation ◽

Low Metallicity ◽

Penetration Depths ◽

Loss Rates

ABSTRACT The so-called transition discs provide an important tool to probe various mechanisms that might influence the evolution of protoplanetary discs and therefore the formation of planetary systems. One of these mechanisms is photoevaporation due to energetic radiation from the central star, which can in principal explain the occurrence of discs with inner cavities like transition discs. Current models, however, fail to reproduce a subset of the observed transition discs, namely objects with large measured cavities and vigorous accretion. For these objects the presence of (multiple) giant planets is often invoked to explain the observations. In our work, we explore the possibility of X-ray photoevaporation operating in discs with different gas-phase depletion of carbon and show that the influence of photoevaporation can be extended in such low-metallicity discs. As carbon is one of the main contributors to the X-ray opacity, its depletion leads to larger penetration depths of X-rays in the disc and results in higher gas temperatures and stronger photoevaporative winds. We present radiation-hydrodynamical models of discs irradiated by internal X-ray + EUV radiation assuming carbon gas-phase depletions by factors of three, 10, and 100 and derive realistic mass-loss rates and profiles. Our analysis yields robust temperature prescriptions as well as photoevaporative mass-loss rates and profiles which may be able to explain a larger fraction of the observed diversity of transition discs.

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Mass loss via solar wind and coronal mass ejections during solar cycles 23 and 24

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1001 ◽

2019 ◽

Vol 486 (4) ◽

pp. 4671-4685 ◽

Cited By ~ 5

Author(s):

Wageesh Mishra ◽

Nandita Srivastava ◽

Yuming Wang ◽

Zavkiddin Mirtoshev ◽

Jie Zhang ◽

...

Keyword(s):

Solar Wind ◽

Mass Loss ◽

Sunspot Number ◽

Loss Rate ◽

Mass Loss Rate ◽

Occurrence Rate ◽

The Sun ◽

Solar Cycles ◽

X Ray ◽

X Ray Background

ABSTRACT Similar to the Sun, other stars shed mass and magnetic flux via ubiquitous quasi-steady wind and episodic stellar coronal mass ejections (CMEs). We investigate the mass loss rate via solar wind and CMEs as a function of solar magnetic variability represented in terms of sunspot number and solar X-ray background luminosity. We estimate the contribution of CMEs to the total solar wind mass flux in the ecliptic and beyond, and its variation over different phases of the solar activity cycles. The study exploits the number of sunspots observed, coronagraphic observations of CMEs near the Sun by SOHO/LASCO, in situ observations of the solar wind at 1 AU by WIND, and GOES X-ray flux during solar cycles 23 and 24. We note that the X-ray background luminosity, occurrence rate of CMEs and ICMEs, solar wind mass flux, and associated mass loss rates from the Sun do not decrease as strongly as the sunspot number from the maximum of solar cycle 23 to the next maximum. Our study confirms a true physical increase in CME activity relative to the sunspot number in cycle 24. We show that the CME occurrence rate and associated mass loss rate can be better predicted by X-ray background luminosity than the sunspot number. The solar wind mass loss rate which is an order of magnitude more than the CME mass loss rate shows no obvious dependency on cyclic variation in sunspot number and solar X-ray background luminosity. These results have implications for the study of solar-type stars.

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X-Ray Observations of Elliptical Galaxies by ASCA Satellite

Symposium - International Astronomical Union ◽

10.1017/s0074180900233317 ◽

1996 ◽

Vol 171 ◽

pp. 412-412

Author(s):

K. Matsushita ◽

K. Makishima

Keyword(s):

Low Temperature ◽

Mass Loss ◽

Elliptical Galaxies ◽

Stellar Mass ◽

Plasma Emission ◽

X Ray ◽

Theoretical Predictions ◽

Long Time ◽

Temperature Component ◽

Hubble Time

Using ASCA, we have confirmed that the ISM of X-ray bright elliptical galaxies are surprisingly metal poor, as compared to the theoretical predictions. In fact the exact values of the derived metallicity depend considerably on the plasma emission codes. However, the overall metallicity cannot be larger than ∼ 1 solar. For low LX/LB galaxies, all the available plasma codes suggest abundances less than half a solar. The ASCA spectra may be compatible with somewhat higher metallicity if we assume there is an additional low-temperature component (e.g. kTe ∼ 0.3 keV). However, the derived abundance can not be over 1 solar. In particular, the Si abundance turns out to be < 1.5 solar, confirming the metal-poor nature of the ISM. These ASCA results are in severe contradiction with most of the SN Ia rate, particularly that of Tammann (1982). Considering further that a fairly long time (109–10yr) is needed for the stellar mass loss to accumulates into the ISM, it is suggested that the SN Ia rate has remained quite low throughout Hubble time.

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X-ray induced stellar mass loss near active galactic nuclei

The Astrophysical Journal ◽

10.1086/166549 ◽

1988 ◽

Vol 331 ◽

pp. 197 ◽

Cited By ~ 18

Author(s):

G. Mark Voit ◽

J. Michael Shull

Keyword(s):

Mass Loss ◽

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Stellar Mass ◽

X Ray

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Mass Loss and Stellar Wind in Massive X-Ray Binaries

Highlights of Astronomy ◽

10.1017/s1539299600004433 ◽

1980 ◽

Vol 5 ◽

pp. 541-547

Author(s):

H. F. Henrichs

Keyword(s):

Mass Loss ◽

Stellar Wind ◽

Binary Systems ◽

Massive Stars ◽

Compact Star ◽

X Rays ◽

Early Type ◽

X Ray ◽

X Ray Binaries ◽

Loss Rates

A number of massive stars of early type is found in X-ray binary systems. The catalog of Bradt et al. (1979) contains 21 sources optically identified with massive stars ranging in spectral type from 06 to B5 out of which 13 are (nearly) unevolved stars and 8 are supergiants. Single stars of this type generally show moderate to strong stellar winds. The X-rays in these binaries originate from accretion onto a compact companion (we restrict the discussion to this type of X-rays).We consider the compact star as a probe traveling through the stellar wind. This probe enables us to derive useful information about the mass outflow of massive stars.After presenting the basic data we derive an upper limit to mass loss rates of unevolved early type stars by studying X-ray pulsars. Next we consider theoretical predictions concerning the influence of X-rays on the stellar wind and compare these with the observations. Finally, using new data from IUE, we draw some conclusions about mass loss rates and velocity laws as derived from X-ray binaries.

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Constraining the Stellar Mass Function in the Galactic Center via Mass Loss from Stellar Collisions

Advances in Astronomy ◽

10.1155/2011/174105 ◽

2011 ◽

Vol 2011 ◽

pp. 1-19 ◽

Cited By ~ 1

Author(s):

Douglas Rubin ◽

Abraham Loeb

Keyword(s):

Mass Loss ◽

Galactic Center ◽

Mass Loss Rate ◽

Mass Function ◽

Stellar Mass ◽

Initial Mass Function ◽

Total Mass Loss ◽

Stellar Collisions ◽

Mass Functions ◽

Loss Rates

The dense concentration of stars and high-velocity dispersions in the Galactic center imply that stellar collisions frequently occur. Stellar collisions could therefore result in significant mass loss rates. We calculate the amount of stellar mass lost due to indirect and direct stellar collisions and find its dependence on the present-day mass function of stars. We find that the total mass loss rate in the Galactic center due to stellar collisions is sensitive to the present-day mass function adopted. We use the observed diffuse X-ray luminosity in the Galactic center to preclude any present-day mass functions that result in mass loss rates>10-5M⨀yr−1in the vicinity of~1″. For present-day mass functions of the form,dN/dM∝M-α, we constrain the present-day mass function to have a minimum stellar mass≲7M⨀and a power-law slope≳1.25. We also use this result to constrain the initial mass function in the Galactic center by considering different star formation scenarios.

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Is there a Connection Between Non-Synchronous Rotation and X-Ray Emission in Massive Binary Systems?

Symposium - International Astronomical Union ◽

10.1017/s0074180900195476 ◽

2004 ◽

Vol 215 ◽

pp. 163-165 ◽

Cited By ~ 2

Author(s):

Sinhué Haro ◽

Juan Antonio Juárez ◽

Gloria Koenigsberger

Keyword(s):

Mass Loss ◽

Orbital Period ◽

Binary Systems ◽

X Ray ◽

Rotating Systems ◽

Tidal Forces ◽

Synchronous Rotation ◽

Massive Binary Systems ◽

Loss Rates

A correlation between orbital period and log(LX/Lbol) is found for a sample of B-type binary systems. We suggest that wind-wind collisions are the likely mechanism for generating the X-ray emission, and that the mass-loss rates may be enhanced in non-synchronously rotating systems due to the oscillations that are excited by the tidal forces.

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