Standard Evolution Models Research Articles

The Place of Attachment in Human Mating

Application of the principles of evolution and natural selection to the phenomena of human mating does not lead inevitably to a single theoretical model. According to the standard evolutionary model, formally known as sexual strategies theory ( D. M. Buss & D. P. Schmitt, 1993 ), biologically based sex differences in parental investment have resulted in hard-wired sex differences in mate preferences and mating strategies. A critical analysis of the logical and empirical foundations of the theory reveals several weaknesses and limitations. This article demonstrates how attachment theory ( J. Bowlby, 1969/1982 , 1973 , 1979 , 1980 , 1988 ) can be used to integrate a diverse set of ideas and research findings and provide a more grounded account of human mating.

Postcolonial Representation of Aboriginal Australian Culture

Postcolonial Representation of Aboriginal Australian Culture

The place of attachment in human mating.

Application of the principles of evolution and natural selection to the phenomena of human mating does not lead inevitably to a single theoretical model. According to the standard evolutionary model, formally known as sexual strategies theory (D. M. Buss & D. P. Schmitt, 1993), biologically based sex differences in parental investment have resulted in hard-wired sex differences in mate preferences and mating strategies. A critical analysis of the logical and empirical foundations of the theory reveals several weaknesses and limitations. This article demonstrates how attachment theory (J. Bowlby, 1969/1982, 1973, 1979, 1980, 1988) can be used to integrate a diverse set of ideas and research findings and provide a more grounded account of human mating.

The strong magnetic fields of the X-ray pulsars Hercules X-1 and 4U 1626–67 and their evolutionary scenarios

We consider the magnetic and spin evolution of the X-ray binary pulsars Her X-1 and 4U 1626–67, assuming that their magnetic fields are of crustal origin. We adopt the standard evolutionary model which implies that the neutron star passes through several phases in a binary system (‘isolated pulsar’ — propeller — wind accretion — Roche lobe overflow). In the framework of the model under consideration, the strong magnetic fields of relatively old pulsars like Her X-1 and 4U 1626–67 can naturally be understood if, at their birth, they had a sufficiently strong magnetic field, ∼3 × 1013 G, comparable to the maximal field observed in radio pulsars.

Keck Spectroscopy of Candidate Proto–Globular Clusters in NGC 1275

?????Keck spectroscopy of five proto?globular cluster candidates in NGC 1275 has been combined with Hubble Space Telescope Wide Field Planetary Camera 2 photometry to explore the nature and origin of these objects and discriminate between merger and cooling-flow scenarios for globular cluster formation. The objects we have studied are not H II regions, but rather star clusters, yet their integrated spectral properties do not resemble young or intermediate-age Magellanic Cloud clusters or Milky Way open clusters. The clusters' Balmer absorption appears to be too strong to be consistent with any of the standard Bruzual & Charlot evolutionary models at any metallicity. If the Bruzual & Charlot models are adopted, an initial mass function (IMF) that is skewed to high masses provides a better fit to the data of the proto?globular cluster candidates. A truncated IMF with a mass range of 2?3 M? reproduces the observed Balmer equivalent widths and colors at ~450 Myr. Formation in a continuous cooling flow appears to be ruled out since the age of the clusters is much larger than the cooling time, the spatial scale of the clusters is much smaller than the cooling-flow radius, and the deduced star formation rate in the cooling flow favors a steep rather than a flat IMF. A merger would have to produce clusters only in the central few kiloparsecs, presumably from gas in the merging galaxies that was channeled rapidly to the center. Widespread shocks in merging galaxies cannot have produced these clusters. If these objects are confirmed to have a relatively flat, or truncated, IMF, it is unclear whether they will evolve into objects that we would regard as bona fide globular clusters.

Political marketing and party development in Britain

Argues that by utilizing a standard evolutionary model of marketing it is possible to map out three key stages in the development of electioneering, each of which is directly comparable with the production, sales and marketing orientations in commerce. In politics the respective phases can be labelled the propaganda, media and marketing approaches to the electorate. Using this framework the differences between the three campaign orientations become self‐evident. Interestingly, it also becomes possible to trace the similarities in approach, specifically the important, if previously largely unrecognized, role that basic marketing concepts have played in British elections since the beginning of the century. Contrary to popular perception, professional advertising and image consciousness are not legacies of the 1980s but date back to the decade following the introduction of near universal suffrage in 1918. The realization of popular television and consumer marketing in the 1950s exacerbated the need for more coherent party image management. Finally in the late 1970s and 1980s both main contenders for government underwent strategic changes akin to embracing a marketing orientation.

Properties of the Exceptionally Long-Period AM Herculis System RX J0515.41+0104.6

view Abstract Citations (8) References (29) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Properties of the Exceptionally Long-Period AM Herculis System RX J0515.41+0104.6 Frank, J. ; Lasota, J. -P. ; Chanmugam, G. Abstract We show that the properties of the recently discovered AM Her type cataclysmic variable RX J0515.41+0104.6 can be understood in terms of the standard evolutionary model, which accounts for both the near-synchronism at the observed period and the size of the mass-donor star. We find that either the system is in a low state long enough to bring the white dwarf to synchronism or that the magnetic field of the secondary is strong enough, but not unusually so (≳1 kG), to maintain synchronism at this period and the system may exhibit radio flares. Publication: The Astrophysical Journal Pub Date: November 1995 DOI: 10.1086/176405 Bibcode: 1995ApJ...453..446F Keywords: STARS: BINARIES: CLOSE; STARS: EVOLUTION; STARS: INDIVIDUAL ALPHANUMERIC: RX J0515.41+0104.6; STARS: NOVAE; CATACLYSMIC VARIABLES full text sources ADS | data products SIMBAD (1)

A photometric and spectrographic study of SX Phoenicis

Simultaneous photometric (uvbyβ) and spectrographic observations of SX Phe are described. Analysis of the light and velocity frequency spectra are performed. It is shown that all frequencies detected are harmonics or combinations of the fundamental and first harmonic frequencies. Intrinsic (b−y) and c 1 values used in conjunction with a model-atmosphere grid appropriate for a star with [M/H]=−1.0 yields =7630 K and =3.90. Standard evolutionary models indicate the mass is 1.13 M ○. and value is +2.9. The radial-velocity data indicate a mean radial velocity of −37 km/s and a total range of 38 km/s

Infall models of galaxy evolution: a solution to the redshift distribution problem?

Galaxy number counts at faint magnitudes exceed the expectations from non-evolving models, based on the present-day galaxy population, by a large margin. Despite this, redshift surveys show that the redshift distribution is as expected in the non-evolving case, lacking in particular the tail of evolved bright galaxies at high z predicted by the standard evolutionary models. We consider here the effect of using a broadly peaked, rather than steadily rising, luminosity evolution model. Evolution of this form has as its physical basis current infall models for the history of star formation in our galaxy

Chromospherically active stars. VIII - HD 155638 = V792 Herculis: Observational constraints on evolutionary theory

view Abstract Citations (13) References (28) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Chromospherically Active Stars. VIII. HD 155683 = V972 Herculis: Observational Constraints on Evolutionary Theory Fekel, Francis C. Abstract V792 Her is an eclipsing RS CVn binary with an orbital period of 27.54 days whose components have spectral types of K0 III and F2 IV. New spectroscopic observations combined with existing photometry have resulted in masses of 1.47 + or - 0.003 solar mass and 1.41 + or - 0.003 solar mass for the K giant and F star, respectively. Additional fundamental parameters are derived. Standard evolutionary models were specifically computed by VandenBerg (1990) for the two stars. The best fit occurs if the components are somewhat metal poor with Fe/H/ = - 0.46. Ages of about 2.3 x 10 to the 9th yr derived for the two components differ by less than 3 percent. Thus, standard evolutionary models with no convective overshoot are able to fit the observed parameters of stars as massive as 1.45 solar mass. However, a definitive comparison is not yet possible since the metal abundance of the stars is unknown and metal-poor convective-overshoot tracks in this mass range are needed. Publication: The Astronomical Journal Pub Date: April 1991 DOI: 10.1086/115781 Bibcode: 1991AJ....101.1489F Keywords: Chromosphere; Eclipsing Binary Stars; Stellar Activity; Stellar Atmospheres; Stellar Evolution; F Stars; Hertzsprung-Russell Diagram; K Stars; Radial Velocity; Stellar Mass; Stellar Spectra; Astrophysics; STARS: RS CVN; STARS: ECLIPSING BINARIES full text sources ADS | data products SIMBAD (8) Related Materials (25) Part 1: 1985AJ.....90.2581F Part 2: 1986AJ.....92.1150F Part 3: 1987AJ.....94..726F Part 4: 1988AJ.....95..215F Part 5: 1988AJ.....96.1426F Part 6: 1989AJ.....97..202F Part 7: 1989AJ.....97.1139F Part 9: 1991AJ....102.1439F Part 10: 1993AJ....105.2265F Part 11: 1993AJ....106.2370F Part 12: 1994AJ....108..694F Part 13: 1994AJ....108.1936F Part 14: 1995AJ....109.2821F Part 15: 1996AJ....112..269F Part 16: 1997AJ....114.2747F Part 17: 1998AJ....115.1153F Part 18: 2000AJ....120.3265F Part 19: 2001AJ....122..991F Part 20: 2001AJ....122.3447F Part 21: 2002AJ....124.1064F Part 22: 2004AJ....127.2303F Part 23: 2004AJ....127.2931F Part 24: 2005AJ....129.1669F Part 25: 2005AJ....130..794F Part 26: 2007AJ....134.2079F

High-resolution CCD spectra of stars in globular clusters. IV - Carbon isotope ratios in red giants

view Abstract Citations (73) References (34) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS High-Resolution CCD Spectra of Stars in Globular Clusters. IV. Carbon Isotope Ratios in Red Giants Brown, Jeffery A. ; Wallerstein, George Abstract Carbon isotope ratios for stars in four globular clusters are derived by means of spectrum synthesis analysis of CN features in high-resolution spectra around 8000 A. In the strong-CN stars in the clusters M4, M22, Omega Cen, and 47 Tuc, the isotope ratios are generally quite low, approaching the equilibrium value in the CN cycle, namely 3-8; this includes a barium star and an S star in Omega Cen and a CH star in M22. (C-13)N is not detected in weak-CN stars, but the limits on the (C-12)/(C-13) ratios in these stars are not significant. Ratios as low as 3-8 are not predicted by standard evolution models of low-mass metal-poor stars. Publication: The Astronomical Journal Pub Date: November 1989 DOI: 10.1086/115248 Bibcode: 1989AJ.....98.1643B Keywords: Carbon Isotopes; Charge Coupled Devices; Globular Clusters; Red Giant Stars; Stellar Spectra; High Resolution; Stellar Evolution; Stellar Mass; Stellar Models; Astrophysics; STARS: ABUNDANCES; CLUSTERS: GLOBULAR full text sources ADS | data products SIMBAD (16) Related Materials (9) Part 1: 1986AJ.....91.1117L Part 2: 1986STIN...8710789L Part 3: 1987AJ.....93..338L Part 4: 1987AJ.....93.1137W Part 6: 1990AJ....100.1561B Part 7: 1991AJ....101.1693B Part 8: 1992AJ....104.1818B Part 9: 1993AJ....106..133B Part 10: 1997AJ....114..180B

SN 1987A - Was Sanduleak -69 deg 202 mixed up?

Stars of mass about 20 solar masses with luminosity and effective temperature in the range observed for SK -69 deg 202, the progenitor of SN 1987A, have a convective zone near the base of the hydrogen-rich envelope. The extent and efficiency of this convective zone are functions of the core and envelope mass, the envelope composition, the luminosity, and the effective temperature. A parameter study is used to establish the conditions under which this convective zone can penetrate the composition barrier at the helium core boundary. For given L, T(eff), and M there is a critical core mass below which core penetration and substantial mixing will occur. This critical core mass is only a few tenths of a solar mass less than the core masses derived in standard evolutionary models. Overshooting (downward) in the convective zone or enhancement of the envelope mass by transfer from a companion could lead naturally to such mixing. Such core penetration will enrich the envelope in helium and nitrogen and might substantially alter the subsequent evolution. 16 refs.

Absolute Dimensions of Algol Binary Systems

In order to check the evolutionary status and theoretical models of eclipsing binaries of Algol type, a reliable determination of their absolute dimensions is needed. In this communication, we compare the most commonly used methods to derive absolute parametors in single-lined aclipsing binaries. Let us first assume that the mass function, f(m), is known from the analysis of the radial velocity curve while the relative radii and orbital inclination are derived from the light curve. The determination of absolute parameters is then equivalent to the obtention of the mass ratio, q = m2/m1. The following methods are available to estimate q from observed parameters — over-all errors being estimated for observational uncertainties of the order of 5 % in relative radii and temperatures and 15 % in f(m) —:1.qs: It is assumed that the primary component follows the mass-luminosity relation for main-sequence stars. This procedure provides qs with an uncertainty of about 10 %.2.qsD: It is assumed that the secondary component fills its Roche lobe. Errors of at least 15 to 20 % are expected from this procedure mainly due to its high sensitivity to small variations in the observed value of r2, particularly if r2 > 0.2.Both methods can be used together when f(m) is doubtful, or completely unknown, but errors can not be expected to be better than in case 2.3.qn: It is assumed that the primary component rotates synchronously in a circular orbit. This assumption is difficult to adopt due to the expected transfer of angular momentum through mass transfer and the value of qn is estimated with about 20 to 30 % error.4.qED: It is assumed that the primary component, is well reproduced by standard evolutionary models within the main sequence. Adopting a grid of models for a given chemical composition, an iterative procedure in the log Ti,.–log g plane permits the determination of m1 and thus q. This method is equivalent to (1) but avoids errors due to evolution from the ZAMS to the TAMS, not taken into account in the previous method, and allows to reach a higher accuracy, around 5 %, except for those primary stars located around the TAMS, where the determination of mi is not unique.

Classical bump Cepheids - Reconciliation of theory with observations

view Abstract Citations (28) References (145) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Classical Bump Cepheids: Reconcilliation of Theory with Observations Carson, T. Richard ; Stothers, Richard B. Abstract New models of classical bump Cepheids lying along the Cepheid ridge line in the H-R diagram are computed to obtain a more accurate set of predicted surface velocity curves. Acceptable Cepheid models are found to be 0.5 mag brighter at a fixed stellar mass than standard evolutionary models. All the previously obtained manifestations of the Cepheid mass discrepancy, except for the anomalous double-mode Cepheid masses, are resolved, at least in a statistical sense, by accepting the implied luminosity increase. The need for the luminosity increase is independently inferred from standard evolutionary models of intermediate-mass and high-mass giant and supergiant stars from their location in the observational H-R diagram. Publication: The Astrophysical Journal Pub Date: May 1988 DOI: 10.1086/166281 Bibcode: 1988ApJ...328..196C Keywords: Cepheid Variables; Hertzsprung-Russell Diagram; Stellar Interiors; Stellar Luminosity; Stellar Oscillations; Binary Stars; Statistical Analysis; Stellar Evolution; Stellar Mass; Supergiant Stars; Astrophysics; OPACITIES; STARS: CEPHEIDS; STARS: INTERIORS; STARS: LUMINOSITIES; STARS: PULSATION full text sources ADS | data products SIMBAD (44)

The Distribution of Faint Galaxies

Faint galaxy data are reviewed in the context of standard evolutionary models and our understanding of the statistical properties of galaxy populations. The differences in number magnitude counts from group to group can largely be understood via fluctuations induced by large scale clustering. However count slopes still present convincing arguments for an extra component of faint blue galaxies beyond B ∼21. Colours provide an useful tool in estimating redshift distributions but the uncertainties are large for the bluest galaxies of interest. However, new faint object redshift surveys are now underway and promise to determine definitively the nature of this extra component. We discuss preliminary results from one of these surveys. Neither distant luminous galaxies nor intrinsically faint nearby galaxies appear to be very numerous to B = 21.5. Many of the galaxies with 0.2 < z < 0.4 show spectral signatures of prominent star-formation. If such objects are somehow related to the excess counts, the traditional redshift-dependent evolutionary theory may require revision.

Opening of the Symposium

The place of stellar physics in Astrophysics is not the same as it were 50 years ago. Stellar evolution theory has been one of the preferred places of numerical calculations, and as a consequence, standard evolution models, from the homogeneous pre-main sequence star to the final stages, white dwarfs, neutron stars, supernovae, has become sort of archetype of numerical analysis and computation, the essence of perfection.

Stellar Winds and Spindown in Solar Type Stars

The angular momentum loss produced by stellar winds is reviewed and a simple model of angular momentum loss with multipole fields is presented in which the field is potential when the flow speed is less than the Alfvén speed, and radial when greater than the Alfvén speed. The simpler the magnetic geometry, the larger is the angular momentum loss rate. This result is used to explain the rotational discontinuity across the Vaughan-Preston gap as being due to a sudden increase in angular momentum loss when the dynamo field switches from a quadropole to a dipole geometry.The evolution of the internal rotation of stars as a result of surface angular momentum loss is considered. In the absence of a magnetic field, differential rotation can drive instabilities which then transport angular momentum out from the interior down the angular velocity gradient. Other instabilities such as that caused by the build up of 3He can also transport angular momentum outwards. If angular momentum is transported by such weak turbulence, it also makes the star more homogeneous than standard evolutionary models and lowers the predicted value of the solar neutrino flux.The recent results on rotational splitting of solar oscillations are considered: these suggest that the inside of the sun is spinning faster than the surface and are compatible with models in which angular momentum is transported by mild turbulence. But data is scarce — and in such circumstances the speculations of the theorist must be viewed with caution!

Comments on the Cluster Main Sequence Fitting Method - Part Two - a Reexamination of the Data for NGC6649 and the Cepheid V367-SCUTI

view Abstract Citations (28) References (24) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Comments on the cluster main-sequence fitting method. II. A reexamination of the data for NGC 6649 and the Cepheid V367 Scuti. Turner, D. G. Abstract Available UBV data for stars in the cluster NGC 6649 are reexamined with a view to a resolution of the discrepancy noted by Flower (1978) between the evolutionary status of the Cepheid V367 Scuti and that of other likely cluster members. The data of Madore and van den Bergh (1975) and Talbert (1975) are combined, and it is shown that a significant amount of differential reddening is present in the cluster. With the effects of this removed, the cluster color-magnitude diagram exhibits far less scatter than has been found previously. As a consequence, the age estimated for cluster members is consistently near 5 (±1) × 107 yr, in agreement with the estimated age of V367 Scuti. Possible uncertainties in the evolutionary status of the luminous B giant members are demonstrated to be a problem inherent to other moderately rich clusters of similar age, and may indicate the need for changes to standard evolutionary models of intermediate-mass stars which account for convective overshooting in the core. It is concluded on the basis of its derived reddening, luminosity, and evolutionary status that V367 Scuti is almost certainly a member of NGC 6649. Publication: The Astronomical Journal Pub Date: February 1981 DOI: 10.1086/112878 Bibcode: 1981AJ.....86..231T full text sources ADS | data products SIMBAD (12) Related Materials (2) Part 1: 1981AJ.....86..222T Part 3: 1989AJ.....98.2300T

Supernova remnants in the Large Magellanic Cloud

view Abstract Citations (60) References (18) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Supernova remnants in the Large Magellanic Cloud. Long, K. S. ; Helfand, D. J. Abstract X-ray emission from 10 previously identified supernova remnants (SNR) in the Large Magellanic Cloud has been discovered in a partially completed survey of this nearby galaxy with the imaging proportional counter on the Einstein Observatory. The X-ray luminosities (0.5-3.0 keV) of these remnants range from 3 x 10 to the 35th to 4 x 10 to the 37th ergs/s. N157B and N158A, whose identifications as SNR were previously based solely on their radio spectra, have been detected as strong X-ray emitters. Two other objects from an optically selected list of candidate SNR were found to coincide with X-ray sources and therefore probably are SNR. The value of obtaining such a uniform sample of SNR at a known distance is illustrated by comparing the properties of the remnants and by fitting standard evolutionary models to the results. Publication: The Astrophysical Journal Pub Date: November 1979 DOI: 10.1086/183113 Bibcode: 1979ApJ...234L..77L Keywords: Heao 2; Magellanic Clouds; Supernova Remnants; X Ray Sources; Astronomical Observatories; Luminosity; Nebulae; Astrophysics; Magellanic Clouds:Supernova Remnants; Supernova Remnants:X Rays; Supernova Remnants:X-Ray Luminosities full text sources ADS |