The kilohertz quasi-periodic oscillations (kHz QPOs) have been found in neutron star low mass X-ray binaries (NS-LMXBs), which present the millisecond timing phenomena close to the surface of the compact objects. We briefly summarize the following contents: (1). The correlations and distributions of twin kHz QPOs; (2). The relations of high-low frequency QPOs; (3). The QPO properties of NS Atoll and Z sources; (4). No clear direct correlations between NS spins and QPOs; (5). The mechanisms of kHz QPOs; (6). The implications of kHZ QPOs, e.g., NS mass and radius, disk thickness and magnetic field of Atoll and Z source.

In a series of works - Török et al. (2010, 2012a) and Urbanec et al. (2010a) - we explored restrictions to neutron star properties that are implied by various models of twin-peak quasi-periodic oscillations. Here we sketch an attempt to confront the obtained mass–angular-momentum relations and limits on neutron star compactness with the parameters estimated by assuming various equations of state and the spin frequency of the atoll source 4U 1636-53.

Recent surface- and volume-density star formation relations have been proposed which potentially unify our understanding of how gas is converted into stars, from the nearest star forming regions to ultra-luminous infrared galaxies. The inner 500 pc of our Galaxy – the Central Molecular Zone – contains the largest concentration of dense, high-surface density molecular gas in the Milky Way, providing an environment where the validity of these star-formation prescriptions can be tested.

We have used recently-available data from HOPS, MALT90 and HiGAL at wavelengths where the Galaxy is transparent, to find the dense, star-forming molecular gas across the Milky Way [Longmore et al. (2012a), Longmore et al. (2012b)]. We use water and methanol maser emission to trace star formation activity within the last 105 years and 30 GHz radio continuum emission from the Wilkinson Microwave Anisotropy Satellite (WMAP) to estimate the high-mass star formation rate averaged over the last ∼ 4 × 106 years.

We find the dense gas distribution is dominated by the very bright and spatially-extended emission within a few degrees of the Galactic centre [Purcell et al. (2012)]. This region accounts for ∼80% of the NH3(1,1) integrated intensity but only contains 4% of the survey area. However, in stark contrast, the distribution of star formation activity tracers is relatively uniform across the Galaxy.

To probe the dense gas vs SFR relationship towards the Galactic centre region more quantitatively, we compared the HiGAL column density maps to the WMAP-derived SFR across the same region. The total mass and SFR derived using these methods agree well with previous values in the literature. The main conclusion from this analysis is that both the column-density threshold and volumetric SF relations over-predict the SFR by an order of magnitude given the reservoir of dense gas available to form stars. The region 1° < l < 3.5°, |b| < 0.5° is particular striking in this regard. It contains ∼107 M⊙ of dense molecular gas — enough to form 1000 Orion-like clusters — but the present-day star formation rate within this gas is only equivalent to that in Orion. This implication of this result is that any universal column/volume density relations must be a necessary but not sufficient condition for SF to occur.

Understanding why such large reservoirs of dense gas deviate from commonly assumed SF relations is of fundamental importance and may help in the quest to understand SF in more extreme (dense) environments, like those found in interacting galaxies and at earlier epochs of the Universe.

We give a new numerical model of pulsar pulse radiation through the interstellar medium (ISM) considering the propagation effects. It explains the deficit of a scattering measure at the decameter range of frequencies that leads to the possibility of detecting the pulsar pulse fine structure. The results of numerical simulation confirm that the fine structure may be detected at low frequencies and this is qualitatively agreed with the observational data.

We observed with HARPS, the Rossiter-McLaughlin effect for 40 of the 75 transiting hot Jupiters discovered in the Southern Hemisphere by WASP. Our observations reveal a wide distribution in orbital inclinations indicative of past dynamical interactions. Our data also demonstrate the important effect produced by tidal interactions in shaping the spin–orbit (β) angle distribution. We briefly present and interpret the data we collected in a series of graphs.

The possibility of a polarization sounding of the pulsar magnetosphere is examined, using intrinsic pulsar emission as a probe signal, for modern radio telescopes operating in the meter and decameter wavelength range. Different models of the pulsar magnetosphere at altitudes higher than a radius of critical polarization are used. The propagation medium besides magnetosphere is described by the stratified model, in which each layer has its own density of free electrons and vector of magnetic induction, as well as the spatial and temporal fluctuation scales of these parameters.

The frequency dependence of the polarization parameters of the pulsar radio emission, obtained in the broad band for a selected pulse phase, will enable a sounding deep into the pulsar magnetosphere.

It is remarkable that the long gamma-ray bursts, as objects connected with the supernovae - i.e. with the end of the massive stars, trace the star formation rate. This connection is discussed in this contribution. The presentation is in essence a recapitulation of the article Mészáros A. et al. A&A, 2006, 455, 785.

The Kennicutt-Schmidt law (Schmidt 1959; Kennicutt 1998, hereafter K-S law) is a power law correlation between area averaged star formation rate (ΣSFR) and gas surface density (Σgas). Despite its importance, the physics that underlie this correlation has remained unclear. The power law index, N, is a prime discriminator of the mechanisms that regulate star formation and form the K-S law (e.g. Leroy et al. 2008; Tan 2010). We present a study of the resolved K-S law for 10 nearby disk galaxies using our new CO(1-0) data at 750 and 500 pc resolutions. The CO(1-0) line emission is established as a tracer of the molecular gas column density, and results in a super-linear correlation (N = 1.3 and 1.8). We discuss the cause of the discrepancy between previous studies, and the mechanism of star formation indicated from our new results.

Observation of pulsar glitches remains a powerful tool for studying the interior of neutron stars. Many of the observed glitch properties are shown to result from the evolution of glitches in the different manifestations of neutron stars. Specifically, the type of glitches associated with the Crab and Vela pulsars are explained by this model. We are, also, able to adequately account for the absence, or very low rate, of glitches among the youngest and the very old pulsars.

We discuss calculations of the star formation, nucleosynthesis, and stochastic evolution of proto-galactic clouds in a galactic chemical evolution model which is motivated by cold dark matter simulations of hierarchical galaxy formation (Saleh et al. 2006; Lan et al. 2010). We utilize SN-induced and dark matter halo formation-induced star formation within a model that follows the evolution of chemical enrichment and energy input to the clouds via Type II, Ia supernovae and stellar winds.

We present quadrupole moments of rotating neutron and strange stars calculated using standard Hartle Thorne approach. We demonstrate differences between neutron and strange star parameters connected with quadrupole moments and how this parameters could be, in the case of neutron stars, approximated almost independently on neutron star equation of state.

We developed a new particle simulation code which includes pair creation (magnetic pair creation and photon collision process), propagation of gamma-ray, inertia of particle, interaction of plasma and multi-pole stellar field for steady axisymmetric pulsar magnetosphere. The photon path is solved stochastically by an analytical solution of the mean free path of pair creation processes at the photon position. The superimposed quadrupole magnetic field forms asymmetric electrostatic clouds on tje poloidal plane and the accelerating region is different from the dipole case. Here, we demonstrate some results of a test run for our simulation. We will adopt the code for more complicated cases, such that all above-mentioned effects will be considered together in future work.

We carry out a multi-wavelength analysis of star forming galaxies in the massive cluster MS0451.6-0305 at z∼0.54 to shed light on the evolution of the far-infrared-radio relationship in rich clusters. We have performed Spectral Energy Distribution (SED) fitting of IRAC 3.6μ, IRAC 4.5μ and MIPS 24μ photometry from Spitzer to derive the total infrared bolometric luminosity of spectroscopically confirmed cluster members with radio counterparts. The radio flux densities were measured from deep Very Large Array (VLA) radio continuum observations. The relationship between the infrared and radio luminosities for our sources show the strong correlation found between these two parameters for star forming galaxies. The far-infrared to radio luminosity ratio (qIR) values measured for these sources are comparable to those measured in low redshift clusters and indicative of an excess of radio emission.

We study the propagation effects of radio waves in a pulsar magnetosphere, composed of relativistic electron-positron pair plasmas streaming along the magnetic field lines and corotating with the pulsar. We critically examine the various physical effects that can potentially influence the observed wave intensity and polarization. We numerically integrate the transfer equations for wave polarization in the rotating magnetosphere, taking account of all the propagation effects in a self-consistent manner. For typical magnetospheric plasma parameters produced by pair cascade, we find that the observed radio intensity and polarization profiles can be strongly modified by the propagation effects. Some applications of our results are discussed.

We present SINFONI observations of IRAS 19115-2124, dubbed the Bird, an intriguing triple galaxy encounter. NIR line strengths and line ratios are used to study the sequence of events in this complex system. The most massive and obscured component shows LINER-like activity, while the least massive irregular component is the source of 3/4 of the current total SF. This most recent compact starburst lies 3 kpc away from the dynamically dominant components. Cool and warm gas inflows and outflows are detected at the locations of the progenitor nuclei.

We obtained HST COS Lyα spectroscopy for 20 galaxies that were Hα-selected from the Kitt Peak International Spectroscopic Survey data release. We cover redshifts of z=0.02–0.06 and a broad range in metallicity, reddening, and luminosity. We investigate correlations between the properties of the Lyα-lines and fundamental properties of the galaxies. Our seven emitters have: equivalent widths in the range EW(Lyα)=1–12 Å, i.e., below the completeness limits of higher redshift studies; extinction corrected Lyα/Hα ratios of at most 12–15% of the case B recombination theory value; and O I λ1302 ISM absorptions blueshifted to 〈v(O I)〉= − 117±40 km/s, which are consistent with H I gas outflows. Six emitters have P-Cygni-like Lyα profiles with peaks redshifted to 〈v〉=172±25 km/s, and one of our face-on spiral galaxies has two Lyα peaks separated by 370 km/s. The latter peaks are such that the blueshifted peak is twice as strong as the redshifted peak. The rest of the galaxies show Lyα absorption troughs centered at 〈v〉=19 km/s and O I λ1302 absorptions centered at 〈v(O I)〉= − 34±25 km/s, which is consistent with static or low velocity H I gas. Our two most metal poor and least reddened galaxies, which have large Hα equivalent widths are absorbers. The spiral galaxies in our sample have Lyα in single emission, double emission, or absorption. There appears to be a correlation between the Hα derived SFR and the strength of the Lyα emission but our sample is small. Our observations cover regions of at most 3 kpc in diameter and may miss a significant fraction of the resonantly scattered Lyα emission. This work is supported by NASA grant N1317.