BM Cas – a long-period eclipsing young supergiant binary system in common envelope stage

Binaries with very wide spearations are thought to evolve to small separations through a catastrophic form of mass exchange/loss known as common-envelope evolution. The theory of this process is fairly well developed, but proper tests remain elusive. Simply put, the theory argues that the rapidly shrinking Roche lobe of the mass losing giant will strip away the giant's main-sequence companion. Loss of mass from the system during the process carries away orbital angular momentum, thereby strengthening the effect.

Download Full-text

Progress of Common Envelope Evolution

Highlights of Astronomy ◽

10.1017/s1539299600007681 ◽

1989 ◽

Vol 8 ◽

pp. 155-159

Author(s):

R. E. Taam

Keyword(s):

Binary System ◽

Time Scale ◽

Binary Systems ◽

Efficiency Factor ◽

Final Phase ◽

Common Envelope ◽

Orbital Decay ◽

Mass Outflow ◽

The Common ◽

Orbital Periods

AbstractThe current understanding of the common envelope binary phase of evolution is presented. The results obtained from the detailed computations of the hydrodynamical evolution of this phase demonstrate that the deposition of energy by the double core via frictional processes is sufficiently rapid to drive a mass outflow, primarily in the equatorial plane of the binary system. Specifically, recent calculations suggest that large amounts of mass and angular momentum can be lost from the binary system in a such a phase. Since the time scale for mass loss at the final phase of evolution is much shorter than the orbital decay time scale of the companion, the tranformation of binary systems from long orbital periods (> month) to short orbital periods (< day) is likely. The energy efficiency factor for the process is estimated to lie in the range between 0.3 and 0.6.

Download Full-text

A type Ia supernova at the heart of superluminous transient SN 2006gy

Science ◽

10.1126/science.aaw1469 ◽

2020 ◽

Vol 367 (6476) ◽

pp. 415-418 ◽

Cited By ~ 5

Author(s):

Anders Jerkstrand ◽

Keiichi Maeda ◽

Koji S. Kawabata

Keyword(s):

Binary System ◽

Light Curve ◽

Supernova Explosion ◽

Large Mass ◽

Late Time ◽

Standard Type ◽

Circumstellar Material ◽

Common Envelope ◽

Type Ia Supernova ◽

Type Ia

Superluminous supernovae radiate up to 100 times more energy than normal supernovae. The origin of this energy and the nature of the stellar progenitors of these transients are poorly understood. We identify neutral iron lines in the spectrum of one such supernova, SN 2006gy, and show that they require a large mass of iron (≳0.3 solar masses) expanding at 1500 kilometers per second. By modeling a standard type Ia supernova hitting a shell of circumstellar material, we produce a light curve and late-time iron-dominated spectrum that match the observations of SN 2006gy. In such a scenario, common envelope evolution of a progenitor binary system can synchronize envelope ejection and supernova explosion and may explain these bright transients.

Download Full-text

The evolutionary status of symbiotic stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100097840 ◽

1982 ◽

Vol 70 ◽

pp. 275-282 ◽

Cited By ~ 2

Author(s):

Bronislaw Rudak

Keyword(s):

Cataclysmic Variables ◽

Evolutionary Status ◽

Spherically Symmetric ◽

Symbiotic Stars ◽

Transfer Phase ◽

Common Envelope ◽

Long Period ◽

Red Giant ◽

Detached Binaries ◽

Rapid Mass

AbstractThe evolutionary relations between symbiotic stars and cataclysmic variables are presented. The symbiotic stars are assumed to be long period detached binaries containing a carbon-oxygen degenerate primary and a red giant losing its mass through a spherically symmetric wind. Such systems can be obtained in Case C evolution, provided a common envelope during a rapid mass transfer phase was not formed. The same way recurrent novae containing a red giant as a secondary component may be produced. The factors influencing the differences between symbiotic stars and nova-type stars are discussed.

Download Full-text

Detection of a pulsar in a long-period binary system

The Astrophysical Journal ◽

10.1086/183191 ◽

1980 ◽

Vol 236 ◽

pp. L25 ◽

Cited By ~ 22

Author(s):

R. N. Manchester ◽

L. M. Newton ◽

D. J. Cooke ◽

A. G. Lyne

Keyword(s):

Binary System ◽

Long Period

Download Full-text

A long-period globular-cluster pulsar in an eclipsing binary system

Nature ◽

10.1038/361047a0 ◽

1993 ◽

Vol 361 (6407) ◽

pp. 47-49 ◽

Cited By ~ 39

Author(s):

A. G. Lyne ◽

J. D. Biggs ◽

P. A. Harrison ◽

M. Bailes

Keyword(s):

Binary System ◽

Globular Cluster ◽

Eclipsing Binary ◽

Long Period

Download Full-text

Extremely long period-stacking structure in the Sb–Te binary system

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768105017714 ◽

2005 ◽

Vol 61 (5) ◽

pp. 492-497 ◽

Cited By ~ 71

Author(s):

Kouichi Kifune ◽

Yoshiki Kubota ◽

Toshiyuki Matsunaga ◽

Noboru Yamada

Keyword(s):

Crystal Structure ◽

Binary System ◽

Atomic Level ◽

Structural Units ◽

Long Period ◽

Synchrotron Powder Diffraction ◽

Δ Phase ◽

Relationship Of ◽

Stacking Structure ◽

Inverse Proportionality

The crystal structure of the δ-phase in the Sb–Te binary system has been determined by synchrotron powder diffraction. It is clearly shown that many intermetallic compounds, which have different stacking periods depending on compound composition, exist in this phase. These structures are based on the cubic ABC stacking structure, and two kinds of fundamental structural units form an intergrowth along the stacking direction at the atomic level. The chemical formulae of these compounds are expressed as Sb2n Te3, where n is an integer and the number of stacking layers is 2n + 3. There is a relationship of inverse proportionality between the stacking period and the Te concentration.

Download Full-text