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Population synthesis of binary relativistic stars

“…A conservative lower limit to the event rate of galactic binary neutron star coalescence of about 1 per 10 6 year follows from double pulsar statistics studies (Narayan et al (1991), Phinney (1991)). Binary population synthesis, however, give much higher values, of about 1 per 3000 -10000 year (Lipunov & Postnov (1987a), Tutukov & Yungelson (1993), Lipunov et al (1995b)). Fortunately, discovery of double pulsars J07373039B (Burgay et al (2003)) close the disagreement between radiopulsars merging rate estimation and population synthesis one (see history on Fig.…”

“…Obviously, this function reaches a minimum value of 2 once C=O for all species. Lipunov et al (1997) compare the calculated ("C") and observed ("O") numbers of binary radio-pulsars with NS (PSR+NS), WD (PSR+WD) and normal OB-stars (PSR+OB). The COOC criterion for binary radio-pulsar species as a function of the mean kick velocity ).…”

“…The history of the Scenario Machine can be briefly summarized as follows: a+e - Kornilov & Lipunov (1983a), Kornilov & Lipunov (1983b) Massive binaries a+e +f - Kornilov & Lipunov (1984) Massive binaries a+b + c+d+e - Lipunov & Postnov (1987b) Low Massive Binaries a + d - Dewey & Cordes (1987) Massive Binaries + radiopulsar evolution a+b+c+d+e+f -Scenario Machine Lipunov & Postnov (1987a), Lipunov & Postnov (1987b), Lipunov & Postnov (1988) The results obtained with the Scenario Machine include the following: 1) Prediction of nearly 100 new stages of binary systems with magnetized compact companions; 2) Prediction of millisecond X-ray accreting pulsars (see Kornilov & Lipunov (1983b)), later confirmed by discovery of A0538-66 (P = 0.067 s); 3)Explanation of some of the ultrasoft superluminous sources as superaccreting compact stars in binaries (Lipunov et al (1993)), which was confirmed by the discovery of a transient X-ray pulsar RX J0059.2-7138 in the Small Magellanic Cloud (SMC) (Hughes (1994)); 4) Prediction of the strong dependence of the X-ray luminosity on star formation history in galaxies; 5) Prediction and estimation of the number of binary radiopulsars with OB-stars (1 per 700 visible galactic pulsars) (Kornilov & Lipunov (1984), ), which was confirmed by discovery of PSR B1259-63 (Johnston et al (1992)); 6) Estimation of the number of binary radiopulsars with black holes (Lipunov (1994)); 7) Calculation of the gravitational wave background formed by galactic and extragalactic binaries (Lipunov & Postnov (1987a), Lipunov & Postnov (1988); Lipunov et al (1995a)); 8) Anisotropy of supernova explosions giving "kick"-velocities of young pulsars of 70-100 km/s (Kornilov & Lipunov (1984); similar estimates are given by Dewey & Cordes (1987)), a more detailed discussion will be given below; 9) A significant evolution of Xray luminosity of the galaxies (discovered on RXTE, Chandra, INTEGRAL) as indicator of star formation rate history (Tatarintzeva et al (1989)); 10) A significant evolution of supernova rates and binary NS merging rates at cosmological distances (Lipunov & Postnov (1988); Lipunov et al (1995b)). …”

Glimpses of Be Binary Evolution

“…Numerical models of this process Portegies Zwart 1995;Lipunov, Postnov, & Prokhorov 1996;Van Bever & Vanbeveren 1997) require input parameters describing (1) binary frequency, (2) the distributions of mass, mass ratio, and period, (3) the fraction of mass accreted versus lost to the system, (4) the angular momentum lost, (5) the distribution of kick velocities for supernovae, and (6) the relative lifetimes in the various stages. There are significant uncertainties about all of these parameterizations, and consequently, the model predictions about the numbers and kinds of binary products remain diverse.…”

The Evolutionary Evidence for Most Be Stars Being Paired with Hot White Dwarfs

“…The calculations have been made using the "Scenario Machine" (a numerical code that models the evolution of large ensembles of binary systems; Lipunov et al 1996). The existence of white dwarf companions of Be stars is of significant importance from an evolutionary standpoint since they must have evolved from massive progenitors, perhaps close to the maximum mass for white dwarf progenitor stars, and they are likely themselves to be much more massive than the mean for white dwarfs in general (0.57 M©, Finley, Koester & Basri 1997).…”