I report recent results of numerical simulations designed to study the inner structure of Cold Dark Matter (CDM) halos. This work confirms the proposal of Navarro, Frenk & White (NFW) that the shape of ACDM halo mass profiles differs strongly from a power law and is approximately independent of mass. the logarithmic slope of the spherically-averaged density profile, as measured by β = –d ln ρ/d ln r, decreases monotonically towards the center, becoming shallower than isothermal (β < 2) inside a characteristic radius, r–2, and shows no evidence for convergence to a well-defined asymptotic value (β0) at the center. the dark mass contained within the innermost radius resolved by the simulations places strong constraints on β0; cusps as steep as r–1.5 are clearly ruled out in our highest resolution simulations. A profile where the radial dependence of the slope is a simple power law, β(r) ∝ rα, approximates the structure of halos better than the NFW profile and so may minimize errors when extrapolating our results inward to radii not yet reliably probed by numerical simulations. We compare the spherically-averaged circular velocity (Vc) profiles to the rotation curves of low surface brightness (LSB) galaxies in the samples of de Blok et al. and Swaters et al. the Vc profiles of simulated CDM halos are generally consistent with the rotation curves of LSB galaxies, but there are also some clearly discrepant cases. This disagreement has been interpreted as excluding the presence of cusps, but it may also just reflect the difference between circular velocity and rotation speed likely to arise in gaseous disks embedded within realistic triaxial halos.

Observational evidence of transient flares which produce conspicuous changes in the total brightness and in the spectra of dwarf stars is limited, at present, to a small number of faint late-type stars. The outbursts take place with extraordinary rapidity and the duration is usually only a few minutes or hours. Accompanying spectral changes such as veiled and fuzzy absorption lines, greatly increased intensity of the bright lines of hydrogen and helium, and the appearance of an emission continuum shortward of λ 3750, have been reported.

We present examples of activity cycle timescales on different types of stars from lowmass dwarfs to more massive giants, with wide-ranging rotation rates, and compare the observed cyclicities to the irradiance based solar cycle and its modulations. Using annual spectral solar irradiance in wavelength bands typical for stellar observations reconstructed by Shapiro et al. (2011), a direct comparison can be made between cycle timescales and amplitudes derived for the Sun and the stars. We show that cycles on multiple timescales, known to be present in solar activity, also show up on stars when the dataset is long enough to allow recognition. The cycle lengths are not fixed, but evolve – gradually during some periods but there are also changes on short timescales. In case the activity is dominated by spots, i.e., by cooler surface features, the star is redder when fainter, whereas other type of activity make the stars bluer when the activity is higher. We found the Sun to be a member of the former group, based on reconstructed spectral irradiance data by Shapiro et al. (2011).

Recent progress in modeling core-collapse supernovae is summarized and set in perspective. Two-dimensional simulations with state-of-the-art treatment of neutrino transport still fail to produce powerful explosions, but evidence is presented that they are very close to a success.

A compilation is given of transition probabilities of forbidden lines which occur in the spectra of gaseous nebulae.

We have developed a method to understand the detailed structure of the mean pulse profile of pulsars, namely, the Gaussian fit separation of the average profile (GFSAP) method, in which we assume the total profile is the superposition of several individual Gaussian-distributed components. Linear polarization data is used to simplify the fitting. The components of PSR 1451–68 are separated and their spectral indices calculated. We find that the profile of PSR 1451–68 is actually quintuple instead of triple, which is in agreement with the idea that quintuple is the prototype shape of pulsar profiles. The core component is shown to have the steepest spectrum, while the inner cone has the flattest. Another conclusion from PSR 1451–68 is that the core width does not change with frequency.

Additional α(16)Λ(9)-photometry of upper main sequence stars with anomalous abundances confirm our previous results, namely, Ap stars are neatly separated from normal main sequence stars. Furthermore, Ap stars are located on three different zones of the α(16)Λ(9)-plane, according to their abundance anomalies to form three photometric groups, (i) Si stars, (ii) Hg,Mn stars, and (iii) Cr,Eu,Sr stars.

It is shown that a number of features of meteor showers such as the correlation of orbital semimajor axes and longitudes of the ascending nodes with meteor magnitudes, the restriction of visibility periods and the displacement of maximum activity dates is explained by the joint influence of planetary perturbations, the Poynting-Robertson effect and its corpuscular analogue, light pressure and ejection velocities of different mass meteoroids from cometary nuclei.

The term extreme ultraviolet (EUV or XUV) is employed in upper atmosphere physics and in solar work where it usually denotes the wavelength band between 100 and 1000 Å. Since thermal emission with 30,000 ≲ T ≲ 300,000 K peaks in this band, it might be expected that studies at these wavelengths would be especially useful for objects with effective temperatures in this range. In fact9 few such studies have been carried out. The reason for this anomaly is that very few EUV studies have been made at all, particularly because of unreasonably pessimistic estimates of the opacity of the interstellar medium and partially because of instrumental difficulties encountered at these wavelengths. The first search for extreme ultraviolet emitting objects was carried out in 1975 with instrumentation on the Apollo spacecraft in the Apollo-Soyuz mission. Four of approximately thirty preselected objects were detected with this instrumentation. The objects detected unquestionably are more a reflection of the prejudices of the investigators than they are a sampling of the contents of the universe. Nonetheless, two of the four objects detected were hot white dwarfs: HZ 43 and Feige 24. In addition, upper limits which turned out to be extremely useful were obtained on the Sirius A/B system. These results, plus more recent results obtained on hot white dwarfs will be discussed in this review.

ζ Ophiuchi and η Centauri are hot, rapidly rotating, southern Be stars showing multi-mode nonradial pulsations (nrp). We use high resolution, high signal-to-noise ratio spectroscopic observations of these objects to test the Telting and Schrijvers’ method (TS) of mode degree l and azimuthal order | m | estimation. In this method, these quantum numbers are calculated from the blue-to-red phase difference of the corresponding main frequency and its first harmonic, respectively. The phase differences were obtained withe the help of the Clean and Cleanest algorithms. Quantum numbers calculated with TS are compatible with those obtained with the Fourier Doppler method within the estimated errors. In the absence of other tools, the TS method can thus be used to estimate l and | m | with reasonably accuracy.

The lightcurves of non-magnetic X-ray binaries are usually modelled using standard techniques developed for ordinary double stars plus some assumptions about the geometry and temperature distribution of the accretion disk. The analyses of the observed optical lightcurves of systems suggest that the disks must have extremely large rims (H/R ~ 0.3) in order to produce the variable obscuration needed to reproduce the often asymmetric lightcurves. However, even models with large rims have problems explaining the X-ray absorption seen in systems with smaller inclinations. We discuss two phenomena which show that non-standard effects in X-ray binaries can play major roles in the determination of the lightcurves: the “spray” caused by the passage of the accretion stream through the “bow-shock” at the outer rim of the disk; and the effects of soft X-ray illumination of the secondary star.

It is both convenient and realistic to regard the solar radio-emission as being composed of a quiet permanent part coming from the whole of the sun's surface, together with a superimposed variable part emitted from centres of activity. The variable part can be further subdivided into various components to which separate reference will be made. The components are almost independent and add to one another to give the solar emission recorded by radio telescopes. For our understanding of the phenomena it would be a great advantage if the components could be completely and reliably segregated but this is not always possible. The results from a wide network of observational stations are recorded in the Quarterly Bulletin of Solar Activity, from which the intensities and characteristics of most of the components may be extracted.

The results of observations aimed at detecting magnetic fields in the Be star λ Eri are reported. The observational data are analyzed both through application of an approximate analytical method and through computation of a number of simple numerical models in view of deriving constraints on the magnetic fields. General conclusions are drawn about future prospects for magnetic field detections in Be stars.

We present results that trace the dynamics of two historical remnants, SN 1006 and SN 1572 (Tycho), for the past two decades. 21-cm radio images of each remnant were recorded during two previous epochs: 1983–1984 and 1991–1994. We obtained third-epoch images of both remnants from 2001 to 2003. After a direct comparison of images from these three epochs, we found the mean radio expansion rate of Tycho now agrees with a previous X-ray expansion study, and for the first time, we have measured the azimuthal expansion rate over the entire rim of SN 1006.

This Special Session is devoted to the secular evolution of disk galaxies. Here ‘secular’ means ‘slow’; i.e., evolution on time scales that are generally much longer than the galaxy crossing or rotation time. Internal and environmentally driven evolution both are covered.

I am indebted to Albert Bosma for reminding me at the 2011 Canary Islands Winter School on Secular Evolution that our subject first appeared in print in a comment made by Ivan King (1977) in his introductory talk at the Yale University meeting on The Evolution of Galaxies and Stellar Populations: ‘John Kormendy would like us to consider the possibility that a galaxy can interact with itself.. . . I'm not at all convinced, but John can show you some interesting pictures.’ Two of the earliest papers that followed were Kormendy (1979a, b); the first discusses the interaction of galaxy components with each other, and the second studies these phenomena in the context of a morphological survey of barred galaxies. The earliest modeling paper that we still use regularly is Combes & Sanders (1981), which introduces the now well known idea that box-shaped bulges in edge-on galaxies are side-on, vertically thickened bars.

It is gratifying to see how this subject has grown since that time. Hundreds of papers have been written, and the topic features prominently at many meetings (e.g., Block et al. 2004; Falcoń-Barroso & Knapen 2012, and this Special Session). My talk here introduces both internal and environmental secular evolution; a brief abstract follows. My Canary Islands Winter School review covers both subjects in more detail (Kormendy 2012). Kormendy & Kennicutt (2004) is a comprehensive review of internal secular evolution, and Kormendy & Bender (2012) covers environmental evolution. Both of these subject make significant progress at this meeting.

Secular evolution happens because self-gravitating systems evolve toward the most tightly bound configuration that is reachable by the evolution processes that are available to them. They do this by spreading – the inner parts shrink while the outer parts expand. Significant changes happen only if some process efficiently transports energy or angular momentum outward. The consequences are very general: evolution by spreading happens in stars, star clusters, protostellar and protoplanetary disks, black hole accretion disks and galaxy disks. This meeting is about disk galaxies, so the evolution most often involves the redistribution of angular momentum.

We now have a good heuristic understanding of how nonaxisymmetric structures rearrange disk gas into outer rings, inner rings and stuff dumped onto the center. Numerical simulations reproduce observed morphologies very well. Gas that is transported to small radii reaches high densities that are seen in CO observations. Star formation rates measured (e.g.) in the mid-infrared show that many barred and oval galaxies grow, on timescales of a few Gyr, dense central ‘pseudobulges’ that are frequently mistaken for classical (elliptical-galaxy-like) bulges but that were grown slowly out of the disk (not made rapidly by major mergers). Our resulting picture of secular evolution accounts for the richness observed in morphological classification schemes such as those of de Vaucouleurs (1959) and Sandage (1961). State-of-the art morphology discussions include the de Vaucouleurs Atlas of Galaxies (Buta et al. 2007) and Buta (2012, 2013).

Pseudobulges as disk-grown alternatives to merger-built classical bulges are important because they impact many aspects of our understanding of galaxy evolution. For example, they are observed to contain supermassive black holes (BHs), but they do not show the well known, tight correlations between BH mass and host properties (Kormendy et al. 2011). We can distinguish between classical and pseudo bulges because the latter retain a ‘memory’ of their disky origin. That is, they have one or more characteristics of disks: (1) flatter shapes than those of classical bulges, (2) correspondingly large ratios of ordered to random velocities, (3) small velocity dispersions σ with respect to the Faber-Jackson correlation between σ and bulge luminosity, (4) spiral structure or nuclear bars in the ‘bulge’ part of the light profile, (5) nearly exponential brightness profiles and (6) starbursts. None of the above classification criteria are 100% reliable. Published disagreements on (pseudo)bulge classifications usually result from the use of diffferent criteria. It is very important to use as many classification criteria as possible. When two or more criteria are used, the probability of misclassification becomes very small.

I also review environmental secular evolution – the transformation of gas-rich, star-forming spiral and irregular galaxies into gas-poor, ‘red and dead’ S0 and spheroidal (‘Sph’) galaxies. I show that Sph galaxies such as NGC 205 and Draco are not the low-luminosity end of the structural sequence (the ‘fundamental plane’) of elliptical galaxies. Instead, Sph galaxies have structural parameters like those of low-luminosity S+Im galaxies. Spheroidals are continuous in their structural parameters with the disks of S0 galaxies. They are bulgeless S0s. S+Im → S0+Sph transformation involves a variety of internal (supernova-driven baryon ejection) and environmental processes (e.g., ram-pressure gas stripping, harassment, and starvation). Improved evidence for galaxy transformation is presented in several papers at this meeting.

We report the discovery of widespread millimeter-wavelength Class I methanol maser emission associated with protostellar molecular outflows in the massive (proto)cluster G11.92−0.61. Our ~0.5″-resolution SMA and ALMA observations of the 229 GHz and 278 GHz Class I transitions reveal seven and twelve candidate masers, respectively: all 229 GHz masers have 278 GHz counterparts, and five are also coincident with 44 GHz Class I masers previously detected with the VLA. For paired masers, the peak intensities at 229 GHz and 278 GHz are correlated. We also find tentative evidence for a correlation between the strength of millimeter-wavelength Class I maser emission and the energy of the associated molecular outflow.

It is well known that the energy for solar eruptions comes from magnetic fields in solar active regions. Magnetic energy storage and dissipation are regarded as important physical processes in the solar corona. With incomplete theoretical modeling for eruptions in the solar atmosphere, activity forecasting is mainly supported with statistical models. Solar observations with high temporal and spatial resolution continuously from space well describe the evolution of activities in the solar atmosphere, and combined with three dimensional reconstruction of solar magnetic fields, makes numerical short-term (within hours to days) solar activity forecasting possible. In the current report, we propose the erupting frequency and main attack direction of solar eruptions as new forecasts and present the prospects for numerical short-term solar activity forecasting based on the magnetic topological framework in solar active regions.

“Galaxies are like people: they depend on both genetics and environment” (van den Bergh 1975)

The Advanced Stokes Polarimeter is a new instrument dedicated to quantitative measurement of vector magnetic fields in lines formed at several heights in the solar atmosphere at high angular resolution. We present results for a small, symmetric sunspot observed under good seeing conditions near disk center on 25 March 1992. The narrow penumbral “spines” of more vertical field reported by Degenhardt and Wiehr (1991) and Title et al. (1992) are clearly seen in these observations. These spines are characterized by higher field strength than the surrounding penumbra. The inferred field azimuth indicates that these spines flare out with height, as would be expected of stronger field intrusions within the background penumbral field. The observations indicate the penumbral field “canopy” extends well beyond the outer edge of the penumbra. Outside of the sunspot, the small flux elements of mixed polarity are nearly vertical in orientation.

The enigmatic oxygen sequence Wolf-Rayet (WO) stars represent a very late stage in massive star evolution, although their exact nature is still under debate. The spectra of most of the WO stars have never been analysed through detailed modelling with a non-local thermodynamic equilibrium expanding atmosphere code. Here we present preliminary results of the first homogeneous analysis of the (apparently) single WOs.