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The standard picture of CV secular evolution predicts a spike in the CV distribution near the observed short-period cutoff P_0 ~ 78 min, which is not observed. We show that an intrinsic spread in minimum (`bounce') periods P_b resulting from a genuine difference in some parameter controlling the evolution can remove the spike without smearing the sharpness of the cutoff. The most probable second parameter is different admixtures of magnetic stellar wind braking (at up to 5 times the GR rate) in a small tail of systems, perhaps implying that the donor magnetic field strength at formation is a second parameter specifying CV evolution. We suggest that magnetic braking resumes below the gap with a wide range, being well below the GR rate in most CVs, but significantly above it in a small tail.

Understanding global-scale orogenic processes related to supercontinents, and their relationship to the secular evolution of the Earth's lithosphere, represent important challenges for Earth scientists today. The record of these processes is preserved in the microstructures, mineral assemblages and mineral compositions of lithospheric rocks exhumed to the Earth's surface. Given a well-characterized microstructural evolution, thermodynamic modelling is the key to quantifying changes in pressure and temperature, with the rate of these changes being provided by rock-forming and accessory mineral-based geochronology. Thus, metamorphic rocks provide Pressure–Temperature–time–deformation (P–T–t–d) data that help to parameterize orogenic processes.

Longevity of famous men. Secular evolution of life-times. A data base of 4 585 points, concerning famous men, allows us to explore the secular evolution of their longevity (life span)_from the 5th century BC to the 20th century. Women have been excluded because of small sample size, and individuals of less than 18 years for lack of justification of their celebrity. After a very unstable and poorly known period, we establish, starting in the 6th century AD, a linear increase (after logarithmic transformation) of the life span. In the same conditions, there is a regular decrease in the variability of the results. We note also that the mean life of famous men is clearly higher than that after 18 years of men in an ordinary population. The characteristics of this evolution are discussed in particular concerning the genetic and environmental parts of their determinism. The utility of a long life span is considered and an hypothesis of protection of the descendants of long life parents is proposed. This parental protection is favourable for their selection.

I examine whether the observed scatter of the mass transfer rates among CVs of a given orbital period can be explained in terms of irradiation-driven mass transfer cycles. I show that, if such cycles work in CVs, they are characterized by an amplitude A and duty cycle d with A d≫1 . On the other hand, as is demonstrated by means of a simple top hat model for the mass transfer variations, observational constraints require that A d . Therefore, irradiation-driven mass transfer cycles are unlikely to be the cause of the observed scatter of the mass transfer rates. Furthermore, I examine whether the supersoft X-ray sources (SSSs) can be explained as ordinary CVs seen in a high state of an irradiation-driven mass transfer cycle. I argue that while it is possible to get a SSS in this way, this mechanism probably cannot account for a sizable fraction of the SSSs.

The secular evolution of the pulsation period of δ Cephei, η Aquilae, and ζ Geminorum during a cumulative total of 577 years suggests wave-like departures about the smooth time trends.

In this paper, we present three qualitatively different scenarios for bulge formation: a secular evolution model in which bulges form after disks and undergo several central starbursts, a primordial collapse model in which bulges and disks form simultaneously, and an early bulge formation model in which bulges form prior to disks. We normalize our models to the local z=0 observations of de Jong & van der Kruit (1994) and Peletier & Balcells (1996) and make comparisons with high redshift observations. We consider model predictions relating directly to bulge-to-disk properties. As expected, smaller bulge-to-disk ratios and bluer bulge colors are predicted by the secular evolution model at all redshifts, although uncertainties in the data are currently too large to differentiate strongly between the models., 19 pages, 6 figures, accepted for publication in the Astrophysical Journal

Mass accretion is the key factor for evolution of galaxies. It can occur through secular evolution, when gas in the outer parts is driven inwards by dynamical instabilities, such as spirals or bars. This secular evolution proceeds very slowly when spontaneous, and can be accelerated when triggered by companions. Accretion can also occur directly through merging of small companions, or more violent interaction and coalescence. We discuss the relative importance of both processes, their time-scale and frequency along a Hubble time. Signatures of both processes can be found in the Milky Way. It is however likely that our Galaxy had already gathered the bulk of its mass about 8-10 Gyr ago, as is expected in hierarchical galaxy formation scenarios.

The stellar spin orientation relative to the orbital planes of multiplanet systems are becoming accessible to observations. For example, 55 Cancri is a system composed of 5 planets orbiting a member of a stellar binary for which a projected obliquity of 72+-12 deg relative to the orbit of the innermost planet has been reported (Bourrier & Hebrard 2014). This large obliquity has been attributed to the perturbation induced by the binary. Here we describe the secular evolution of similar systems and we discuss the case of the 55 Cancri system more deeply. We provide two different orbital configurations compatible with the currently available observations., Accepted for publication in the proceedings of IAU Symposium 310: Complex Planetary Systems

This article has been accepted for publication in Monthly Notices Royal Astronomical Society ©: 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved, The details of bulge formation via collapse, mergers, secular processes or their interplay remain unresolved. To start answering this question and quantify the importance of distinct mechanisms, we mapped a sample of three galactic bulges using data from the integral field spectrograph WiFeS on the ANU's 2.3-m telescope in Siding Spring Observatory. Its highresolution gratings (R ~ 7000) allow us to present a detailed kinematic and stellar population analysis of their inner structures with classical and novel techniques. The comparison of those techniques calls for the necessity of inversion algorithms in order to understand complex substructures and separate populations. We use line-strength indices to derive single stellar population equivalent ages and metallicities. Additionally, we use full spectral fitting methods, here the code STECKMAP, to extract their star formation histories. The high quality of our data allows us to study the 2D distribution of different stellar populations (i.e. young, intermediate and old). We can identify their dominant populations based on these age-discriminated 2D light and mass contribution. In all galactic bulges studied, at least 50 per cent of the stellar mass already existed 12 Gyr ago, more than currently predicted by simulations. A younger component (age between ~1 and ~8 Gyr) is also prominent and its present day distribution seems to be affected much more strongly by morphological structures, especially bars, than the older one. This in-depth analysis of the three bulges supports the notion of increasing complexity in their evolution, likely to be found in numerous bulge structures if studied at this level of detail, which cannot be achieved by mergers alone and require a non-negligible contribution of secular evolution, MKS acknowledges the support of the Instituto de Astrofísica de Canarias via an Astrophysicist Resident fellowship and Ignacio Martín-Navarro, Andra Stroe and Stéphane Courteau for useful discussions. RC acknowledges the Ministerio de Ciencia e Innovación by means of their FPI program (grant AYA- 2010-21322-C03-03 and AYA-2013-48226-C3-3-P). JFB acknowledges support from the Ramón y Cajal Program and from the FP7 Marie Curie Actions of the European Commission, via the Initial Training Network DAGAL under REA grant agreement number 289313. TRL thanks the support of the Spanish Ministerio de Educación, Cultura y Deporte by means of the FPU fellowship. This research has been supported by the Spanish Ministry of Economy and Competitiveness (MINECO; grants AYA2010-21322-C03-02 and AYA2009-11137) and by the Spanish Ministry of Science and Innovation (MICINN; grants AYA2011-24728 and Consolider-Ingenio CSD2010-00064) and by the Junta de Andalucía (FQM-108)

The increase in life expectancy at all ages during the last two centuries is in need of a quantitative model capable of resuming the whole process under a single concept and simple mathematics. The basic hypothesis was that through improved hygiene, medicine, and life-style, the stumbling blocks to the full expression of longevity were progressively removed. The mathematics of learning processes was then applied to the secular evolution of life expectancy at various ages. The hypothesis proved very fertile. Logistic equations fit long strings of statistical data, covering the evolution of life expectancy at various ages, for both sexes, and in many European nations for almost two centuries. These life expectancy increases seem to move progressively to a common asymptote of about 79 years for men and about 84 years for women. It is suggested that these values are taken as a definition of longevity, presumably explicitating a coding in DNA. The evolution of life expectancy during the last couple of centuries appears to follow consistent paths precisely mapped with simple mathematics. This opens the way to more integrated and holistic theories.

Self-gravitating systems evolve toward the most tightly bound configuration that is reachable via available evolution processes. The inner parts shrink and the outer parts expand, provided that some physical process transports energy or angular momentum outward. The evolution of stars, star clusters, protostellar and protoplanetary disks, black hole accretion disks, and galaxy disks are all fundamentally similar. These processes for galaxy disks are the subjects of my lectures and of this Canary Islands Winter School. Part 1 discusses formation, growth, and death of bars. Part 2 details the slow ("secular") rearrangement of angular momentum that results from interactions between stars or gas and nonaxisymmetries such as bars. We have a heuristic understanding of how this forms outer rings, inner rings, and stuff dumped into the center. Observations show that barred galaxies have central concentrations of gas and star formation. Timescales imply that they grow central "pseudobulges" that get mistaken for elliptical-galaxy-like classical bulges but that formed gently out of disks. Part 3 shows how we distinguish between classical and pseudo bulges. Part 4 reviews how environmental secular evolution transforms gas-rich, star-forming spirals and irregulars into gas-poor, red and dead S0 and spheroidal ("Sph") galaxies. Sphs are not ellipticals; they have structural parameters like those of low-luminosity S+Im galaxies. So Sphs are bulgeless S0s. Part 5 combines hierarchical clustering and secular evolution into a comprehensive picture.

The formation and evolution of galaxies is one of the most important topics in astrophysics. Secular evolution refers to the relatively slow dynamical evolution due to internal processes induced by a galaxy's spiral arms, bars, galactic winds, black holes and dark matter haloes. It plays an important role in the evolution of spiral galaxies with major consequences for galactic bulges, the transfer of angular momentum, and the distribution of a galaxy's constituent stars, gas and dust. This internal evolution is key to understanding cosmological models of galaxy formation and evolution. Based on the twenty-third Winter School of the Canary Islands Institute of Astrophysics, this volume presents reviews from nine experts on the observational and theoretical research into secular processes, and what these processes can tell us about the structure and formation of galaxies. The volume provides a grounding for graduate students and researchers working on galactic dynamics and galaxy evolution.

[Abridged] We analyse the morphological structures in galaxies of the ATLAS3D sample by fitting a single Sersic profile and decomposing all non-barred objects (180 of 260 objects) in two components parameterised by an exponential and a general Sersic function. The aim of this analysis is to look for signatures of discs in light distributions of nearby early-type galaxies and compare them to kinematic properties. Using Sersic index from single component fits for a distinction between slow and fast rotators, or even late- and early-type galaxies, is not recommended. Assuming that objects with n>3 are slow rotators (or ellipticals), there is only a 22 per cent probability to correctly classify objects as slow rotators (or 37 per cent of previously classified as ellipticals). We show that exponential sub-components, as well as light profiles fitted with only a single component of a low Sersic index, can be linked with the kinematic evidence for discs in early-type galaxies. The median disk-to-total light ratio for fast and slow rotators is 0.41 and 0.0, respectively. Similarly, the median Sersic indices of the bulge (general Sersic component) are 1.7 and 4.8 for fast and slow rotators, respectively. Overall, discs or disc-like structures, are present in 83 per cent of early-type galaxies which do not have bars, and they show a full range of disk-to-total light ratios. Discs in early-type galaxies contribute with about 40 per cent to the total mass of the analysed (non-barred) objects. The decomposition into discs and bulges can be used as a rough approximation for the separation between fast and slow rotators, but it is not a substitute, as there is only a 59 per cent probability to correctly recognise slow rotators. Kinematics (i.e. projected angular momentum) remains the best approach to mitigate the influence of the inclination effects., Accepted for publication in MNRAS. 29 pages 14 figures. More information about our Atlas3D project is available at http://purl.org/atlas3d

[Context] Galaxy mergers are widely discussed as one possible evolution mechanism for lenticular galaxies (S0s), because even minor mergers induce structural changes that are difficult to reconcile with the strong bulge-disk coupling observed in the photometric scaling relations of these galaxies., [Aims] We check if the evolution induced onto S0s by dry intermediate and minor mergers can reproduce the S0 photometric scaling relations., [Methods] We analyse the bulge-disk decompositions of the collisionless N-body simulations of intermediate and minor mergers onto S0s presented previously to determine the evolution induced by the mergers in several relevant photometric planes., [Results] The mergers induce an evolution in the photometric planes that is compatible with the data of S0s, even in the relations that indicate a strong bulge-disk coupling. Mergers drive the formation of the observed photometric relation in some cases and induce a slight dispersion compatible with data in others. Therefore, this evolutionary mechanism tends to preserve the observational photometric relations. In the photometric planes where the morphological types segregate, the mergers always induce evolution towards the region populated by S0s. No clear trends with the mass ratio of the encounter, the central satellite density, or the spin-orbit coupling are found for the range of values studied. Long-pericentre orbits generate more concentrated disks and expanded bulges than initially, while short-pericentre orbits do the opposite. The structural coupling of the bulge and the disk is preserved or reinforced in the models because mergers trigger internal secular processes in the primary disk that induce significant bulge growth. This happens even though the encounters do not induce bars in the disks., [Conclusions] Intermediate and minor mergers can be considered to be plausible mechanisms for the evolution of S0s if one includes their photometric scaling relations, because they can preserve and even strengthen any pre-existing structural bulge-disk coupling by triggering significant internal secular evolution, even without bars or dissipational effects. Satellite accretions thus seem to unavoidably entail internal secular evolution, meaning that it may be quite complex to isolate the effects of the internal secular evolution driven by mergers from the one due to purely intrinsic disk instabilities in individual early-type disks at the present., Supported by the Spanish Ministry of Science and Innovation (MICINN) under projects AYA2009-10368, AYA2006-12955, AYA2010-21887-C04-04, AYA2009-11137, and AYA2012-30717, and by the Madrid Regional Government through the AstroMadrid Project (CAM S2009/ESP-1496, http://www.laeff.cab.inta-csic.es/projects/astromadrid/main/index.php). Funded by the Spanish MICINN under the Consolider-Ingenio 2010 Program grant CSD2006-00070: “First Science with the GTC” (http://www.iac.es/consolider-ingenio-gtc/), and by the Spanish programme of International Campus of Excellence Moncloa (CEI). A.C.G.G. is a Ramon y Cajal Fellow of the Spanish MICINN.

We consider the secular evolution of the orbits of bodies in the Outer Solar System under the perturbations of the jovian planets assumed on coplanar and circular orbits. Through the approach used for asteroidal belt by Yoshihide Kozai in 1962, we obtain that the Kozai resonance do not affect the behavior of bodies belonging to the Kuiper belt but concerns the long-timescale evolution of long-period comets. In particular this resonance appears as a process contributing to produce Sun-grazer comets.

The contracts drawn up in the 18th century between European captains and Ottoman charterers state precisely the currency to be used for payment. The exploitation, on this point, of 1719 contracts, written in both Maghrib and Machrek Ottoman harbours, has concerned three periods, 1686-1707, 1754-1767 and 1791-1794. It reveals a secular evolution characterized by the simultaneous and successive circulation of numerous ottoman and european currencies and the persistency of two distinguished areas of use, the Maghrib and the Levant, which expresses the diversity and the upholding of these areas, long after they joined the Ottoman empire.

Aims. We locate escape routes from the main asteroid belt, particularly into the near-Earth-object (NEO) region, and estimate the relative fluxes for different escape routes as a function of object size under the influence of the Yarkovsky semimajor-axis drift.Methods. We integrated the orbits of 78 355 known and 14 094 cloned main-belt objects and Cybele and Hilda asteroids (hereafter collectively called MBOs) for 100 Myr and recorded the characteristics of the escaping objects. The selected sample of MBOs with perihelion distance q > 1.3 au and semimajor axis a V V We find more than ten obvious escape routes from the asteroid belt to the NEO region, and they typically coincide with low-order mean-motion resonances with Jupiter and secular resonances. The locations of the escape routes are independent of the semimajor-axis drift rate and thus are also independent of the asteroid diameter. The locations of the escape routes are likewise unaffected when we added a model for Yarkovsky-O’Keefe-Radzievskii-Paddack (YORP) cycles coupled with secular evolution of the rotation pole as a result of the solar gravitational torque. A Yarkovsky-only model predicts a flux of asteroids entering the NEO region that is too high compared to the observationally constrained flux, and the discrepancy grows larger for smaller asteroids. A combined Yarkovsky and YORP model predicts a flux of small NEOs that is approximately a factor of 5 too low compared to an observationally constrained estimate. This suggests that the characteristic timescale of the YORP cycle is longer than our canonical YORP model predicts.

Bulges are not just elliptical subgalaxies situated in the centers of large spirals. It might seem that way from their ages and chemistry, but bulge kinematics have been known to be different since the first long slit spectra were obtained. M31 presents the best opportunity to investigate all the issues of the stellar populations of bulges. This review collects the array of probing data that has been accumulated in the last decade. But the intriguing question `how did it form like this ?' remains., Comment: submitted to PASA

PurposeRegionalization of care for ST-segment elevation myocardial infarction (STEMI) has been advocated, although its effect on processes of care – compared with secular evolution – remains uncertain. The aim of this study was to evaluate the impact of a regional system of care on reperfusion strategies for STEMI patients relative to control hospitals.MethodsWe analysed the original data from two nationwide, prospective cohort studies, with the same methods. The fisrt was conducted in November 2000 (FAST MI 2010) and the second in November 2005 (FAST MI 2005). A total of 160 French hospitals participated in both studies. Seven hospitals (2 with percutaneous coronary intervention facilities and 5 without) were involved in a regional system of care implemented in the Northern Alps in 2002 (RESURCOR); 153 control hospitals were located in other French areas with no corresponding regional system of care. From 2002 to 2005, RESURCOR promoted prehospital fibrinolysis followed by routine/rescue coronary angiography. We compared change in rate of prehospital fibrinolysis and routine/rescue coronary angiography after fibrinolysis between 2000 and 2005 in the RESURCOR region versus the control hospitals.ResultsA total of 102 STEMI patients were enrolled in the Northern Alps hospitals and 2377 in the control hospitals. In the RESURCOR area we observed a larger absolute increase in the use of prehospital fibrinolysis (18% vs 63%, P

Supermassive black holes launching plasma jets at close to speed of light, producing gamma-rays, have ubiquitously been found to be hosted by massive elliptical galaxies. Since elliptical galaxies are generally believed to be built through galaxy mergers, active galactic nuclei (AGN) launching relativistic jets are associated to the latest stages of galaxy evolution. We have discovered a pseudo-bulge morphology in the host galaxy of the gamma-ray AGN PKS 2004-447. This is the first gamma-ray emitter radio loud AGN found to be launched from a system where both black hole and host galaxy have been actively growing via secular processes. This is evidence for an alternative black hole-galaxy co-evolutionary path to develop powerful relativistic jets that is not merger-driven., 20 pages, 4 figures. Astrophysical Journal, accepted

Dating the First Solids The solar system's first solids: calcium-aluminum–rich inclusions and chondrules are found in meteorites and provide a direct record of the dynamics of the solar protoplanetary disk that led to the formation of the solar system. Previous results indicate that chondrules formed 1 to 2 million years after the inclusions—an age difference that has been used in constructing models of chondrule formation. Based on uranium- and lead-isotope measurements of a collection of these primitive materials, Connelly et al. (p. 651 ) show that chondrules in fact started to form at the same time as the inclusions, 4.567 billion years ago, and that their formation took about 3 million years.

We determine central values and radial trends in the stellar populations of the bulges of a sample of 28 edge-on S0-Sb disk galaxies, 22 of which are boxy/peanut-shaped (and therefore barred). Our principal findings are the following. (1) At a given velocity dispersion, the central stellar populations of galaxies with boxy/peanut-shaped bulges are indistinguishable from those of early-type (elliptical and S0) galaxies. Either secular evolution affects stellar populations no differently to monolithic collapse or mergers, or secular evolution is not important in the central regions of these galaxies, despite the fact that they are barred. (2) The radial metallicity gradients of boxy/peanut-shaped bulges are uncorrelated with velocity dispersion and are, on average, shallower than those of unbarred early-type galaxies. This is qualitatively consistent with chemodynamical models of bar formation, in which radial inflow and outflow smears out pre-existing gradients.

We study C/O white dwarfs with masses of 1.0 to 1.4 Msun accreting solar-composition material at very high accretion rates. We address the secular changes in the WDs, and in particular, the question whether accretion and the thermonuclear runaways result is net accretion or erosion. The present calculation is unique in that it follows a large number of cycles, thus revealing the secular evolution of the WD system. We find that counter to previous studies, accretion does not give rise to steady state burning. Instead, it produces cyclic thermonuclear runaways of two types. During most of the evolution, many small cycles of hydrogen ignition and burning build a helium layer over the surface of the white dwarf. This He layer gradually thickens and progressively becomes more degenerate. Once a sufficient amount of He has accumulated, several very large helium burning flashes take place and expel the accreted envelope, leaving no net mass accumulation. The results imply that such a system will not undergo an accretion induced collapse, nor will it lead to a SN Type Ia, unless a major new physical process is found., 8 pages, 7 figures, submitted to MNRAS

What are the main drivers of activity in the local universe? Observations have been instrumental in identifying the mechanisms responsible for fueling activity in galaxy nuclei. In this context we summarize the main results of the NUclei of GAlaxies (NUGA) survey. The aim of NUGA is to map, at high resolution and high sensitivity, the distribution and dynamics of the molecular gas in the central kiloparsec region of 25 galaxies, and to study the different mechanisms responsible for gas fueling of low-luminosity AGNs (LLAGN). Gas flows in NUGA maps reveal a wide range of instabilities. The derived gravity torque maps show that only about 1/3 of NUGA galaxies show evidence of ongoing fueling. Secular evolution and dynamical decoupling are seen to be key ingredients to understand the AGN fueling cycle. We discuss the future prospects for this research field with the advent of instruments like the Atacama Large Millimeter Array (ALMA)., 6 pages, 3 figures, Proceedings of "The Central Kiloparsec in Galactic Nuclei-Astronomy at High Angular Resolution 2011", to appear in Journal of Physics, Conf Series, IOP Publishing

Both the Earth’s Moon and Pluto’s moon, Charon, have an important fraction of the mass of their systems, and therefore they could be classified as double-planets rather than as satellites. The proto-planetary disk is unlikely to produce such systems, and their origin seems to be due to a catastrophic impact of the initial planet with a body of comparable dimensions (e.g. Canup, 2005; Canup & Asphaug, 2001). On the other hand, Neptune’s moon, Triton, and the Martian moon, Phobos, are spiraling down into the planet, clearly indicating that the present orbits are not primordial, and may have undergone a long evolving process from a previous capture (e.g. Goldreich et al., 1989; Mignard, 1981).

Bars and spirals are among the main drivers of the secular evolution of galactic disks, and it is, thus, of prime importance to better understand their exact nature and dynamics. In this respect, the Milky Way provides a unique laboratory in which to study a snapshot of their detailed dynamical influence in six-dimensional phase-space. With the advent of present and future astrometric and spectroscopic surveys, such six-dimensional phase-space data can be obtained for stars in an increasingly large volume around the Sun. Here, we review the signatures of - and constraints on - disk non-axisymmetries obtained from recent stellar kinematical data sets, including (i) the detection of resonant moving groups in the solar neighbourhood, (ii) the non-zero value of the Oort constants C and K, and (iii) the detection of a radial velocity gradient of 4 km/s/kpc in the extended solar neighbourhood (d, 6 pages, 4 figures, invited review at "Assembling the Puzzle of the Milky Way", Grand Bornand, April 2011, eds. C. Reyle, A. Robin, M. Schultheis

Bulges can be classified into classical and pseudobulges; the former are considered to be end products of galactic mergers and the latter to form via secular evolution of galactic disks. Observationally, bulges of disk galaxies are mostly pseudobulges, including the Milky Way's. We here show, by using self-consistent cosmological simulations of galaxy formation, that the formation of pseudobulges of Milky Way-sized disk galaxies has mostly completed before disk formation; thus the main channel of pseudobulge formation is not secular evolution of disks. Our pseudobulges form by rapid gas supply at high-redshift and their progenitors would be observed as high-redshift disks., 3 pages, 2 figures, to appear in the proceedings of `First Stars IV - from Hayashi to the future', M. Umemura, K. Omukai (eds.)

We address the effects of bar-driven secular evolution in discs by comparing their properties in a sample of nearly 700 unbarred and barred (42 +- 3 per cent of the population) massive disc galaxies (M* > 10^10 Msun). We make use of accurate structural parameters derived from i-band bulge/disc/bar decompositions to show that, as a population, barred discs tend to have fainter central surface brightness (Delta mu_0 ~ 0.25 mag), and disc scale lengths that are ~15 per cent larger than those of unbarred galaxies of the same stellar mass. The corresponding distributions of mu_0 and h are statistically inconsistent at the 5.2 sigma and 3.8 sigma levels, respectively. Bars rarely occur in high-surface brightness discs, with less than 5 per cent of the barred population having mu_0 < 19.5 mag arcsec^-2 -- compared to 20 per cent for unbarred galaxies. They tend to reside in moderately blue discs, with a bar fraction that peaks at (g-i)_disc ~ 0.95 mag and mildly declines for both bluer and redder colours. These results demonstrate noticeable structural differences between the discs of barred and unbarred galaxies, which we argue are the result of bar-driven evolution -- in qualitative agreement with longstanding theoretical expectations., 6 pages, 4 figures. Accepted for publication in MNRAS

With the aim of constructing accurate two-dimensional maps of the stellar mass distribution in nearby galaxies from Spitzer Survey of Stellar Structure in Galaxies 3.6 and 4.5 mu m images, we report on the separation of the light from old stars from the emission contributed by contaminants. Results for a small sample of six disk galaxies (NGC 1566, NGC 2976, NGC 3031, NGC 3184, NGC 4321, and NGC 5194) with a range of morphological properties, dust content, and star formation histories are presented to demonstrate our approach. To isolate the old stellar light from contaminant emission (e.g., hot dust and the 3.3 mu m polycyclic aromatic hydrocarbon (PAH) feature) in the IRAC 3.6 and 4.5 mu m bands we use an independent component analysis (ICA) technique designed to separate statistically independent source distributions, maximizing the distinction in the [3.6]-[4.5] colors of the sources. The technique also removes emission from evolved red objects with a low mass-to-light ratio, such as asymptotic giant branch (AGB) and red supergiant (RSG) stars, revealing maps of the underlying old distribution of light with [3.6]-[4.5] colors consistent with the colors of K and M giants. The contaminants are studied by comparison with the non-stellar emission imaged at 8 mu m, which is dominated by the broad PAH feature. Using the measured 3.6 mu m/8 mu m ratio to select individual contaminants, we find that hot dust and PAHs together contribute between similar to 5% and 15% to the integrated light at 3.6 mu m, while light from regions dominated by intermediate-age (AGB and RSG) stars accounts for only 1%-5%. Locally, however, the contribution from either contaminant can reach much higher levels; dust contributes on average 22% to the emission in star-forming regions throughout the sample, while intermediate-age stars contribute upward of 50% in localized knots. The removal of these contaminants with ICA leaves maps of the old stellar disk that retain a high degree of structural information and are ideally suited for tracing stellar mass, as will be the focus in a companion paper.

We present Expanded Very Large Array (EVLA) D-array observations in the 21-cm line of neutral hydrogen (HI) of CIG 292, an isolated SA(s)b galaxy at a distance of ~ 24.3Mpc. From previous HI single dish observations the galaxy was known to have a mildly asymmetric HI profile (A_flux =1.23 {\pm}0.3). Our EVLA observations show there is ~ 12% more HI projected South of the optical centre (approaching velocities) than in the North (receding velocities), despite the HI extending ~ 16% further to the North than the South. The HI projected within the optical disk must have been perturbed within the HI relaxation time (~ 10^8 yr) which implies that this can not have been caused by any of the three nearest companions, as their distance (~ 0.5Mpc) is too large. Neither HI-rich companions nor tidal tails were found within our field of view and velocity range covered. Our kinematical data suggest that the inner part harbors an oval distortion whereas the outer regions show signs of a modest warp. The mild asymmetry in the HI global profile thus actually masks stronger asymmetries in the two-dimensional distributions of gas and star forming regions in this galaxy. Since the galaxy is isolated, this must predominantly be due to processes related to its formation and secular evolution., Comment: 14 pages, 4 figures

G. Orban de Xivry∗†a, R. Daviesa, M. Schartmanna,b, S. Komossaa,c,d,e, A. Marconi f , E. Hicksg, H. Engela, L. Tacconia aMax Planck Institut fur extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching, Germany bUniversitats-Sternwarte Munchen, Scheinerstrasse 1, D-81679 Munchen, Germany cTechnische Universitat Munchen, Fakultat fur Physik, James-Franck-Strasse, 85748 Garching, Germany dExcellence Cluster Universe, TUM, Boltzmannstrasse 2, 85748 Garching, Germany eMax Planck Institut fur Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany f Dipartimento di Fisica e Astronomia, Universita degli Studi di Firenze, Largo E. Fermi 2, 50125 Firenze, Italy gDepartment of Astronomy, University of Washington, Box 351580, Seattle, WA 98195, USA E-mail: xivry@mpe.mpg.de

It has been known for some time that the Milky Way is a barred disk galaxy. More recently several studies inferred from starcount observations that the Galaxy must contain a separate, new, flat long bar component, twisted relative to the barred bulge. Here we use a simulation with a boxy bulge and bar to suggest that these observations can be reproduced with a single structure. In this simulation a stellar bar evolved from the disk, and the boxy bulge originated from it through secular evolution and the buckling instability. We calculate starcount distributions for this model at different longitudes and latitudes, in a similar way as observers have done for resolved starcounts. Good agreement between the simulation and the observations can be achieved for a suitable snapshot, even though the simulation has a single boxy bulge and bar} structure. In this model, part of the long bar signature is due to a volume effect in the starcounts, and another part is due to chosing a snapshot in which the planar part of the boxy bulge and bar has developed leading ends through interaction with the adjacent spiral arm heads. We also provide predictions from this model for the line-of-sight velocity distributions at the longitudes with the long bar signature, for comparison with upcoming surveys., Comment: 4 pages, 5 figures, accepted for publication in ApJL

Stellar bars are important for the secular evolution of disk galaxies because they can drive gas into the galactic central regions. To investigate the star formation properties in barred galaxies, we presented a multi-wavelength study of two barred galaxies NGC 2903 and NGC 7080. We performed the three-component bulge-disk-bar decomposition using the 3.6 {\mu}m images, and identified the bulges in the two galaxies as pseudobulges. Based on the narrowband H{\alpha} images, the star formation clumps were identified and analyzed. the clumps in the bulge regions have the highest star formation rate surface densities in both galaxies, while the star formation activities in the bar of NGC 2903 are more intense than those in the bar of NGC 7080. Finally, we compared with the scenario of bar-driven secular evolution in previous studies, and discussed the possible evolutionary stages of the two galaxies., Comment: 17 pages, 5 figures, 3 tables, accepted for publication in RAA

With the aim of characterizing rejuvenation processes in early-type galaxies, we analyzed five barred S0 galaxies showing prominent outer ring in ultraviolet (UV) imaging. We analyzed GALEX far- (FUV) and near- (NUV) UV and optical data using stellar population models and estimated the age and the stellar mass of the entire galaxies and of the UV-bright ring structures. Outer rings consist of young (, 23 pages, 5 figures and 2 tables, Accepted for publication in The Astrophysical Journal

We present a study of the stellar populations of ring and/or arm-like structures in a sample of S0 galaxies using GALEX far- and near-ultraviolet imaging and SDSS optical data. Such structures are prominent in the UV and reveal recent star formation. We quantitatively characterize these rejuvenation events, estimating the average age and stellar mass of the ring structures, as well as of the entire galaxy. The mass fraction of the UV-bright rings is a few percent of the total galaxy mass, although the UV ring luminosity reaches 70% of the galaxy luminosity. The integrated colors of these S0s locates them in the red sequence (NGC 2962) and in the so-called green valley. We suggest that the star formation episodes may be induced by different triggering mechanisms, such as the inner secular evolution driven by bars, and interaction episodes., Comment: Conference "UV Universe 2010" S. Petersburg 31 May 3 June 2010, Accepted for publication in Astrophysics & Space Science. The final publication is available at http://www.springerlink.com

A classical nova may accrete a non-homogeneousenvelope, which can result in the ignition of a local thermonuclear runaway on the surface of the white dwarf. We studied the propagation of thermal flows along the meridian in the hydrogen rich envelope, to find the conditions under which a thermonuclear runaway is not spherically symmetric. We included mass accretion and tested the effect of temperature inhomogeneities in the secular evolution of the envelope, supposing perturbations with different wavelengths, ranging from very small to comparable with the radius of the white dwarf. The calculations were stopped at the onset of a thermonuclear runaway, when the hydrodynamic expansion starts. We found the ranges of accretion rates and masses of white dwarfs for which the runaway ignites locally. The propagation time of the runaway along the meridian may be as long as days and weeks. “Local” thermonuclear runaways can explain the asymmetries and inhomogeneities of the nova shells and account for the slow rise time to maximum (about one week) of many novae.

Using data from the Near-Infrared S0 Survey (NIRS0S) of nearby, early-type galaxies, we examine the distribution of bar strengths in S0 galaxies as compared to S0/a and Sa galaxies, and as compared to previously published bar strength data for Ohio State University Bright Spiral Galaxy Survey (OSUBSGS) spiral galaxies. Bar strengths based on the gravitational torque method are derived from 2.2 micron Ks-band images for a statistical sample of 138 (98 S0, 40 S0/a,Sa) galaxies having a mean total blue magnitude, Accepted for publication in the Astrophysical Journal, September 2010 issue (LaTex, 29 pages + 3 figures, uses aastex.cls)

Recent results are reviewed on galaxy dynamics, bar evolution, destruction and re-formation, cold gas accretion, gas radial flows and AGN fueling, minor mergers. Some problems of galaxy evolution are discussed in particular, exchange of angular momentum, radial migration through resonant scattering, and consequences on abundance gradients, the frequency of bulgeless galaxies, and the relative role of secular evolution and hierarchical formation., 7 pages, 3 figures, Proceedings of IAU Symp. 271, Astrophysical Dynamics: from Stars to Galaxies, ed. N. Brummell & A.S. Brun, Cambrige Univ Press

We use ~8,600 >5e10 Msol COSMOS galaxies to study how the morphological mix of massive ellipticals, bulge-dominated disks, intermediate-bulge disks, bulge-less disks and irregular galaxies evolves from z=0.2 to z=1. The morphological evolution depends strongly on mass. At M>3e11 Msol, no evolution is detected in the morphological mix: ellipticals dominate since z=1, and the Hubble sequence has quantitatively settled down by this epoch. At the 1e11 Msol mass scale, little evolution is detected, which can be entirely explained with major mergers. Most of the morphological evolution from z=1 to z=0.2 takes place at masses 5e10 - 1e11 Msol, where: (i) The fraction of spirals substantially drops and the contribution of early-types increases. This increase is mostly produced by the growth of bulge-dominated disks, which vary their contribution from ~10% at z=1 to >30% at z=0.2 (cf. the elliptical fraction grows from ~15% to ~20%). Thus, at these masses, transformations from late- to early-types result in disk-less elliptical morphologies with a statistical frequency of only 30% - 40%. Otherwise, the processes which are responsible for the transformations either retain or produce a non-negligible disk component. (ii) The bulge-less disk galaxies, which contribute ~15% to the intermediate-mass galaxy population at z=1, virtually disappear by z=0.2. The merger rate since z=1 is too low to account for the disappearance of these massive bulge-less disks, which most likely grow a bulge via secular evolution., 5 pages, 3 figures, submitted to ApJL

We describe two morphological structures of barred galaxies with the help of numerical simulations. The first one is a feature seen in face-on barred galaxies, the ansae, probably very important dynamically speaking. The second one are the Boxy/Peanut bulges in disc galaxies. They have been associated to stellar bars, and are a result of the secular evolution of barred galaxies. We analyze their properties in a large sample of N-body simulations, using different methods to measure their strength, shape and possible asymmetry, and then inter-compare the results. Some of these methods can be applied to both simulations and observations. In particular, we seek correlations between bar and peanut properties, which, when applied to real galaxies, will give information on bars in edge-on galaxies, and on peanuts in face-on galaxies.

Secular evolution gradually shapes galaxies by internal processes, in contrast to early cosmological evolution which is more rapid. An important driver of secular evolution is the flow of gas from the disk into the central regions, often under the influence of a bar. In this paper, we review several new observational results on bars and nuclear rings in galaxies. They show that these components are intimately linked to each other, and to the properties of their host galaxy. We briefly discuss how upcoming observations, e.g., imaging from the Spitzer Survey of Stellar Structure in Galaxies (S4G), will lead to significant further advances in this area of research.

In this paper we prove the validity of formal asymptotic results on perturbation theory for kink solutions of the sine-Gordon equation, originally obtained by McLaughlin and Scott. We prove that for appropriate perturbations, of size β in an appropriate norm, slowly varying in time in the rest frame of the kink, the shape of the kink is unaltered in the L°° norm to 0(e) for a time of 0 ί - 1 . The kink parameters, which represent its velocity and centre, evolve slowly in time in the way predicted by the asymptotics. The method of proof uses an orthogonal decomposition of the solution into an oscillatory part and a one-dimensiona l "zero-mode" term. The slow evolution of the kink parameters is chosen so as to suppress secular evolution of the zero-mode.

We present a study of large-scale bars in field and cluster environments out to redshifts of ~0.8 using a final sample of 945 moderately inclined disk galaxies drawn from the EDisCS project. We characterize bars and their host galaxies and look for relations between the presence of a bar and the properties of the underlying disk. We investigate whether the fraction and properties of bars in clusters are different from their counterparts in the field. The total optical bar fraction in the redshift range z=0.4-0.8 (median z=0.60), averaged over the entire sample, is 25% (20% for strong bars). For the cluster and field subsamples, we measure bar fractions of 24% and 29%, respectively. We find that bars in clusters are on average longer than in the field and preferentially found close to the cluster center, where the bar fraction is somewhat higher (~31%) than at larger distances (~18%). These findings however rely on a relatively small subsample and might be affected by small number statistics. In agreement with local studies, we find that disk-dominated galaxies have a higher optical bar fraction (~45%) than bulge-dominated galaxies (~15%). This result is based on Hubble types and effective radii and does not change with redshift. The latter finding implies that bar formation or dissolution is strongly connected to the emergence of the morphological structure of a disk and is typically accompanied by a transition in the Hubble type. (abridged), Comment: 17 pages, accepted for publication in A&A

Aims: We show the existence of a small family of inner-galaxy dust lanes and dust lane standing shocks beyond the two major ones that were previously known to exist Methods: We analyze images of CO emission in the inner regions of the Galaxy Results: The peculiar kinematics of the major dust lane features are repeated in several other distinct instances at l > 0deg, in one case at a contrary location 100 pc above the galactic equator at l > 3degr at the upper extremity of Clump 2. Like the previously-known dust lanes, these new examples are alsoassociated with localized, exceptionally broad line profiles believed to be characteristic of the shredding of neutral gas at the standing dust lane shocks. Conclusions: There may be secondary dust lane and standing shocks in the Milky Way bulge. The vertical structure provides a temporal sequence for understanding the secular evolution of gas flow in the bar.

The secular evolution of solar activity and the Sun–Earth relationships have been important research topics of the scientific community throughout the last century. This whole type of investigation needed a variable that was able to provide information on the state of the Sun. For historical reasons, the variables used have depended fundamentally on the sunspots (number of groups of sunspots, Wolf number, sunspot area, etc.). Recently, because the Sun is now monitored practically using almost the whole electromagnetic spectrum and particle flux, the number of indices that give us information on the state of the Sun has increased considerably, although the time series are very short.