Division IX provides a forum for astronomers engaged in the planning, development, construction, and calibration of optical and infrared telescopes and instrumentation, as well as observational procedures including data processing. A few years ago, discussions were started about changes in the structure of Division IX, with the aim of bringing it more in line with today's world of large coordinated projects and multi-national observatories. The course of this process, and further steps to be taken in the period from 2009 to 2012, were at the focus of the deliberations at the business meeting of Division IX at the IAU General Assembly in Rio de Janeiro.

Observations have shown that the Sun's magnetic field has helical structures. The helicity content in magnetic field configurations is a crucial constraint on the dynamical evolution of the system. Since helicity is connected with the number of links we investigate configurations with interlocked magnetic flux rings and one with unlinked rings. It turns out that it is not the linking of the tubes which affects the magnetic field decay, but the content of magnetic helicity.

The early solar observations of Covington (1947) established a good relation between 10.7 cm solar flux and the presence of sunspots on solar disk. The first spatially resolved observation with a two-element interferometer at arc min resolution by Kundu (1959) found that the radio source at 3 cm has a core-halo structure; the core is highly polarized and corresponds to the umbra of a sunspot with magnetic fields of several hundred gauss, and the halo corresponds to the diffuse penumbra or plage region. The coronal temperature of the core was interpreted as due to gyroresonance opacity produced by acceleration of electrons gyrating in a magnetic field. Since the opacity is produced at resonant layers where the frequency matches harmonics of the gyrofrequency, the radio observation could be utilized to measure the coronal magnetic field. Since this simple interferometric observation, the next step for solar astronomers was to use arc second resolution offered by large arrays at cm wavelengths such as Westerbrock Synthesis Radio Telescope and the Very Large Array, which were primarily built for cosmic radio research. Currently, the Owens Valley Solar Array operating in the range 1-18 GHz and the Nobeyama Radio Heliograph at 17 and 34 GHz are the only solar dedicated radio telescopes. Using these telescopes at multiple wavelengths it is now possible to explore three dimensional structure of sunspot associated radio sources and therefore of coronal magnetic fields. We shall present these measurements at wavelengths ranging from 1.7 cm to 90 cm and associated theoretical developments.

Mercury-manganese (HgMn) stars were considered to be non-magnetic, showing no evidence of surface spots. However, recent investigations revealed that some stars in this class possess an inhomogeneous distribution of chemical elements on their surfaces. According to our current understanding, the most probable mechanism of spot formation involves magnetic fields. Taking the advantage of a newly-built polarimeter attached to the HARPS spectrometer at the ESO 3.6m-telescope, we performed a high-precision spectropolarimetric survey of a large group of HgMn stars. The main purpose of this study was to find out how typical it is for HgMn stars to have weak magnetic fields. We report no magnetic field detection for any of the studied objects, with a typical precision of the longitudinal field measurements of 10 G and down to 1 Gauss for some of the stars. We conclude that HgMn stars lack large-scale magnetic fields typical of spotted magnetic Ap stars and probably lack any fields capable of creating and sustaining chemical spots. Our study confirms that alongside the magnetically altered atomic diffusion, there must be other structure formation mechanism operating in the atmospheres of late-B main sequence stars.

In this work we show that protons can exhibit both superdiffusive and ballistic propagation, at variance with standard diffusion. We carry out an analysis of impulsive solar energetic particle (SEP) events, for which the observed time profile of energetic particle fluxes represent the propagator of the corresponding transport equation. We show that in the case of superdiffusive or ballistic transport the propagator in the time asymptotic regime has a power law form, and that a fit of the observed time profiles allows to determine the transport regime. Using data obtained from ACE and SoHO spacecraft, two proton and electron events, which exhibit both superdiffusive and ballistic transport, will be shown. The finding of these anomalous regimes implies that no finite mean free path can be defined.

We will present our campaign to estimate the projected spin-orbit angle for transiting hot Jupiters, obtained via observations of the Rossiter-McLaughlin effect. Combining our results to those of other teams we show what the current distribution in projected spin-orbit angle is, quickly reminding what interpretation we make of it. Finally we will show early results from a campaign that we initiated, surveying the Rossiter-McLaughlin effect on transiting SB1 intended to provide a comparison sample to the transiting planet's results.

Luminous infrared galaxies (LIRGs) are galaxies with LIR > 1011 L⊙. For a star-forming galaxy to emit at a LIRG level, it must have a very high star formation rate (SFR). In the local Universe, the star formation (SF) is primarily triggered by interactions. However, at intermediate redshift, a large fraction of LIRGs are disk galaxies with little sign of recent merger activity. The question arises whether the intermediate redshift LIRGs are “triggered” or experiencing “normal”, if elevated, SF. Understanding these SF processes is important since this type of systems may have contributed to 20% or more of the cosmic SFR in the early Universe. In order to address this issue we study similar systems in the Local Universe, that is isolated late-type galaxies displaying LIRG activity. We use different observational techniques in order to trace the star-forming history of these systems. Here we present preliminary results.

We investigate conditions in a radially self-similar outflow in the regime of large resistivity. Using the PLUTO code, we performed simulations with proper choice of boundary conditions, relaxed at the footpoints of critical surfaces in the flow. We investigate outflow propagation in a high-resistive disk corona, and compare it to the results with small or vanishing resistivity.

Recent numerical studies have focused their interest on the impact outflows have on the cloud's turbulence. The contradictory results obtained by these studies indicate that it is essential for observers to provide the required data to constrain the models. Here we discuss the impact of outflows on the environment surrounding clusters of young stellar objects, from an observer's point of view. We have conducted several studies of outflows in different active star-forming regions. In all cases it is clear that outflows have the power to sustain the observed turbulence in the gas surrounding protostellar clusters. We investigate whether there is a correlation between outflow strength and star formation efficiency, as predicted by numerical simulations, for six different regions in the Perseus molecular cloud complex. We argue that results of other recent studies that use CO line maps to study the turbulence driving length should not be used to discard outflows as major drivers of turbulence in clusters.

Longterm continuous X-ray observations of blazars with MAXI are reported. Thanks to its unprecedentedly high sensitivity as an all sky X-ray monitor, MAXI is an ideal observatory to investigate variability of blazars, which should give a clue to particle acceleration in their jet, as well as the jet dynamics. Actually, since it started its operation in the summer of 2009, MAXI has successfully alerted two strong X-ray flares from the BL Lac object Mrk 421. Especially, in one of these flares, the X-ray flux of the object was found to become the highest in history. By closely examining the MAXI data, the physical quantities associated with the flares were estimated. These results clearly demonstrate the potential of MAXI for the variability of blazars.

The Business Meeting for Commission 25 was held on the 6th of August 2009. The meeting was chaired by Dr Eugene Milone, Vice President for the 2006-2009 triennium, and incoming President for the 2009-2011 triennium. Dr Milone presented an apology from the President of the Commission, Dr Peter Martinez, who was unable to attend the meeting.

The pre-stellar cores in which low mass stars form are generally well magnetized. Our simulations show that early protostellar discs are massive and experience strong magnetic torques in the form of magnetic braking and protostellar outflows. Simulations of protostellar disk formation suggest that these torques are strong enough to suppress a rotationally supported structure from forming for near critical values of mass-to-flux. We demonstrate through the use of a 3D adaptive mesh refinement code – including cooling, sink particles and magnetic fields – that one produces transient 1000 AU discs while simultaneously generating large outflows which leave the core region, carrying away mass and angular momentum. Early inflow/outflow rates suggest that only a small fraction of the mass is lost in the initial magnetic tower/jet event.

The formal origin of the IRWG occured at the Buenos Aires General Assembly, following a Joint Commission meeting at the IAU GA in Baltimore in 1988 that identified the problems with ground-based infrared photometry. The situation is summarized in Milone (1989). In short, the challenges involved how to explain the failure to achieve the milli-magnitude precision expected of infrared photometry and an apparent 3% limit on system transformability. The proposed solution was to redefine the broadband Johnson system, the passbands of which had proven so unsatisfactory that over time effectively different systems proliferated, although bearing the same JHKLMNQ designations; the new system needed to be better positioned and centered in the atmospheric windows of the Earth's atmosphere, and the variable water vapour content of the atmosphere needed to be measured in real time to better correct for atmospheric extinction.

Many hot Jupiters are observed to be misaligned with respect to the rotation axis of the star (as measured through the Rossiter–McLaughlin effect) and some (about ~ 25%) even appear to be in retrograde orbits. We show that the presence of an additional, moderately inclined and eccentric massive planet in the system can naturally explain close, inclined, eccentric, and even retrograde orbits. We have derived a complete and accurate treatment of the secular dynamics including both the key octupole-order effects and tidal friction. The flow of angular momentum from the inner orbit to the orbit of the perturber can lead to both high eccentricities and inclinations, and even flip the inner orbit. In our treatment the component of the inner orbit's angular momentum perpendicular to the stellar equatorial plane can change sign; a brief excursion to very high eccentricity during the chaotic evolution of the inner orbit can then lead to rapid “tidal capture,” forming a retrograde hot Jupiter. Previous treatments of the secular dynamics focusing on stellar-mass perturbers would not allow for such an outcome, since in that limit the component of the inner orbit's angular momentum perpendicular to the stellar equatorial plane is strictly conserved. Thus, the inclination of the planet's orbit could not change from prograde to retrograde.

We study the effects of different approximations of scattering in 3D radiation-hydrodynamics simulations on the photospheric temperature stratification of metal-poor red giant stars. We find that assuming a Planckian source function and neglecting the contribution of scattering to extinction in optically thin layers provides a good approximation of the effects of coherent scattering on the photospheric temperature balance.

Observations of sun-like stars rotating faster than our current sun tend to exhibit increased magnetic activity as well as magnetic cycles spanning multiple years. Using global simulations in spherical shells to study the coupling of large-scale convection, rotation, and magnetism in a younger sun, we have probed effects of rotation on stellar dynamos and the nature of magnetic cycles. Major 3-D MHD simulations carried out at three times the current solar rotation rate reveal hydromagnetic dynamo action that yields wreaths of strong toroidal magnetic field at low latitudes, often with opposite polarity in the two hemispheres. Our recent simulations have explored behavior in systems with considerably lower diffusivities, achieved with sub-grid scale models including a dynamic Smagorinsky treatment of unresolved turbulence. The lower diffusion promotes the generation of magnetic wreaths that undergo prominent temporal variations in field strength, exhibiting global magnetic cycles that involve polarity reversals. In our least diffusive simulation, we find that magnetic buoyancy coupled with advection by convective giant cells can lead to the rise of coherent loops of magnetic field toward the top of the simulated domain.

Due to its proximity, size, complex structure and high inclination angle, M31 offers an excellent opportunity for studying galactic structures outside the Milky Way and for drawing implications for their cosmological origin. We have studied the stellar populations of M 31 using the Sloan Digital Sky Survey (SDSS) photometry and the Spitzer far-infrared (FIR) mappings of dust. Combining these data, we have constructed a 3-dimensional model of the galaxy, laying constraints on the intrinsic (dust-free) properties of the galaxy and its stellar populations: their apparent and intrinsic luminosities, luminosity distributions, colours, shapes and sizes. We have interpreted the derived spectral energy distributions with synthetic stellar populations created with the Starburst99 software, in order to constrain the ages and masses of the stellar components.

We report on the detection of a strong, organized magnetic field in the helium-variable early B-type star HR 7355 using spectropolarimetric data obtained with ESPaDOnS on CFHT by the MiMeS large program. We also present results from new V-band differential photometry obtained with the CTIO 0.9m telescope. We investigate the longitudinal field, using a technique called Least-Squares Deconvolution (LSD), and the rotational period of HR 7355. These new observations strongly support the proposal that HR 7355 harbors a structured magnetosphere similar to that in the prototypical helium-strong star, σ Ori E.

We suggest the existence of two BLRs in 3C 390.3 which have different locations. The BLR1 is located at a distance in accordance to the hydrogen line time lags of ≈20 days. This disk-like region emits predominantly low ionization lines. The BLR2 forms around the radio-jet and is located at the distance corresponding to time lags of ≈ 40-80 days. The BLR2 is responsible for most of the emission in UV lines. The Lα line partly forms in BLR2 (40-60%) and partly in BLR1.

We studied numerically electron acceleration by a perpendicular wavy shock. Distribution function of accelerated electrons is highly anisotropic, with many sharp peaks. The peaks are caused by (usually single) reflections of electrons by the shock and subsequent transmission.