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With several large aperture optical and IR telescopes just coming on-line, or scheduled for the near future, solar physics is on the verge of a quantum leap in observational capabilities. An efficient use of such facilities will require new and innovative approaches to both observatory operations and data handling.
This two-days long Special Session discussed the science expected with large solar telescopes, and started addressing the strategies necessary to optimize their scientific return. Cutting edge solar science as derived from state-of-the-art observations and numerical simulations and modeling was presented, and discussions were held on the role of large facilities in satisfying the demanding requirements of spatial and temporal resolution, stray-light correction, and spectro-polarimetric accuracy. Building on the experience of recently commissioned telescopes, critical issues for the development of future facilities were discussed. These included operational issues peculiar to large telecopes as well as strategies for their best use.
We explore the connection between black hole growth at the center of obscured quasars selected from the XMM-COSMOS survey and the physical properties of their host galaxies. We study a bolometric regime (<Lbol> ∼ 8 × 1045 erg s−1) where several theoretical models invoke major galaxy mergers as the main fueling channel for black hole accretion. To derive robust estimates of the host galaxy properties, we use an SED fitting technique to distinguish the AGN and host galaxy emission. We find that at z ∼ 1, ≈ 62% of Type-2 QSOs hosts are actively forming stars and that their rates are comparable to those measured for normal star-forming galaxies. The fraction of star-forming hosts increases with redshift: ≈ 71% at z ∼ 2, and 100% at z ∼ 3. We also find that the evolution from z ∼ 1 to z ∼ 3 of the specific star-formation rate of the Type-2 QSO hosts is in excellent agreement with that measured for star-forming galaxies.
We have applied theoretical models to explain spectral energy distribution (SED) of three radio-loud broad absorption line (BAL) quasars: an extended hybrid object PG 1004+130 and two compact sources 1045+352 and 3C270.1. We calculate the emission from the very inner part of the sources which accounts for more than 90% of the observed X-ray radiation. In our analysis we consider a scenario in which the observed X-ray emission comes from the inverse-Compton (IC) scattering inside a jet and from the accretion disk corona. The compact objects 1045+352 and 3C270.1 are high-redshift quasars (z = 1.604 and 1.532 respectively), with strong radio cores. We argue that in the case of these two sources a non-thermal, inverse-Compton emission from the innermost parts of the jet can explain a large fraction of the observed X-ray emission. The large scale object PG 1004+130 with a peculiar radio morphology is a low-redshift (z = 0.24), lobe-dominated BAL quasar with a weak radio core. In this case simulated inverse-Compton X-ray emission of the jet is relatively low. However, the corona emission appears strong enough to explain the observed X-ray spectrum of this object.
The discovery of a pulsar (PSR) in orbit around a black hole (BH) is expected to provide a superb new probe of relativistic gravity and BH properties. Apart from a precise mass measurement for the BH, one could expect a clean verification of the dragging of space-time caused by the BH spin. In order to measure the quadrupole moment of the BH for testing the no-hair theorem of general relativity (GR), one has to hope for a sufficiently massive BH. In this respect, a PSR orbiting the super-massive BH in the center of our Galaxy would be the ultimate laboratory for gravity tests with PSRs. But even for gravity theories that predict the same properties for BHs as GR, a PSR-BH system would constitute an excellent test system, due to the high grade of asymmetry in the strong field properties of these two components. Here we highlight some of the potential gravity tests that one could expect from different PSR-BH systems, utilizing present and future radio telescopes, like FAST and SKA.
We present a measurement of the trigonometric parallax of IRAS 05168+3634 with VERA. The parallax is 0.532 ± 0.053 milli-arcsec, corresponding to a distance of 1.88+0.21−0.17 kpc. This is significantly closer than the previous distance estimate of 6 kpc based on a kinematic distance measurement. This drastic change in the source distance implies the need for revised values of not only the physical parameters of IRAS 05168+3634, but it also impies a different location in the Galaxy, placing it in the Perseus arm rather than the Outer arm. We also measured the proper motion of the source. A combination of the distance and proper motion with the systemic velocity yields a rotation velocity Θ = 227+9−11 km s−1 at the source position, assuming Θ0 = 240 km s−1. Our result, combined with previous VLBI results for six sources in the Perseus arm, indicates that the sources rotate systematically more slowly than the Galactic rotation velocity at the local standard of rest. In fact, we derive peculiar motions in the disk averaged over the seven sources in the Perseus arm of (Umean, Vmean) = (11 ± 3, −17 ± 3) km s−1, which indicates that these seven sources are moving systematically toward the Galactic Center and lag behind the overall Galactic rotation.
Raman scattering of far UV photons with atomic hydrogen is important in studying the mass loss and accretion processes in many symbiotic stars. We present basic atomic physical properties for the inelastic scattering of He II 949 with a hydrogen atom, which results in Raman scattered He II 4332 blueward of H gamma. At line center of He II 949, the total scattering cross section is computed to be σtot = 2.5 × 10−22 cm2 and the branching ratio into the level 2s is 0.12. It is proposed that comparisons of broad Balmer wings and Raman scattered He II features may provide an important diagnostic of far UV continuum around H I Lyman series.
We test a nonlinear force-free field (NLFFF) optimization code in spherical geometry with an analytical solution from Low and Lou. The potential field source surface (PFSS) model is served as the initial and boundary conditions where observed data are not available. The analytical solution can be well recovered if the boundary and initial conditions are properly handled. Next, we discuss the preprocessing procedure for the noisy bottom boundary data, and find that preprocessing is necessary for NLFFF extrapolations when we use the observed photospheric magnetic field as bottom boundaries. Finally, we apply the NLFFF model to a solar area where four active regions interacting with each other. An M8.7 flare occurred in one active region. NLFFF modeling in spherical geometry simultaneously constructs the small and large scale magnetic field configurations better than the PFSS model does.
I would like to outline briefly, at first, an introduction to the Pyongyang Astronomical Observatory(PAO) and the present status of PAO. Next, I will mention about its future strategic plan for the development of astronomy research and education as well as the public outreach in DPRK, and the ways and means for its achievement, mainly emphasizing the international cooperation and support by the IAU such as via ROAD and cooperation programs.
Studying the properties of the few compact massive galaxies that exist in the local Universe (Trujillo et al. 2009) might provide a closer look to the nature of their high redshift (z ≥ 1.0) massive counterparts. By this means we have characterized their main kinematics, structural properties, stellar populations and star formation histories with a set of new high quality spectroscopic and imaging data (Ferré-Mateu et al. 2012 and Trujillo et al. 2012). These galaxies seem to be truly unique, as they do not follow the characteristic kinematics, stellar surface mass density profiles and stellar population patterns of present-day massive ellipticals or spirals of similar mass. They are, instead, more alike their high-z analogs.
Summarizing, local compact massive galaxies are rare, unique and the perfect laboratory to study their high redshift counterparts.
The black hole mass and spin estimates assuming various specific models of the 3 : 2 high frequency quasi-periodic oscillations (HF QPOs) have been carried out in Török et al. (2005, 2011). Here we briefly summarize some current points. Spectral fitting of the spin a ≡ cJ/GM2 in the microquasar GRS 1915 + 105 reveals that this system can contain a near extreme rotating black hole (e.g., McClintock et al., 2011). Confirming the high value of the spin would have significant consequences for the theory of the HF QPOs. The estimate of a > 0.9 is almost inconsistent with the relativistic precession (RP), tidal disruption (TD), and the warped disc (WD) model. The epicyclic resonance (Ep) and discoseismic models assuming the c- and g- modes are instead favoured. However, consideration of all three microquasars that display the 3 : 2 HF QPOs leads to a serious puzzle because the differences in the individual spins, such as a = 0.9 compared to a = 0.7, represent a generic problem almost for any unified orbital 3:2 QPO model.
We present a summary of a three-year academic research proposal drafted during the Sao Paulo Advanced School of Astrobiology (SPASA) to prepare for upcoming observations of tidally locked planets orbiting M-dwarf stars. The primary experimental goal of the suggested research is to expose extremophiles from analogue environments to a modified space simulation chamber reproducing the environmental parameters of a tidally locked planet in the habitable zone of a late-type star. Here we focus on a description of the astronomical analysis used to define the parameters for this climate simulation.
A preliminary distance etimate to SMC 108.1.14904, a long-period eclipsing binary in the Small Magellanic Cloud, is presented. The binary system contains two bright, non-active G-type giants. Its orbital period is 185 days and the orbit is circular. Using surface brightness calibration, we obtain a distance modulus to the system of (m-M)= 19.02 ± 0.04 (statistical) ± 0.05 (systematic) mag, where the systematic error is dominated by uncertainties in the surface brightness calibration. This is a second eclipsing binary in the SMC analysed by our team.
The origin of the large-scale magnetic fields remains an open question, despite the efforts and the continual detection of magnetic fields in the universe. Primordial magnetism could answer the question of cosmic magnetogenesis, but there are still obstacles to overcome.
We report on cross-matching the ROSAT All-Sky Survey and the XMM-Newton catalogs with the Kepler Input Catalog (KIC). For several stars associated with X-ray sources, we provide also an access to our high-resolution spectroscopic observations.
The 2mass Tully–Fisher Survey (2mtf) aims to measure Tully–Fisher (TF) distances for all bright, inclined spirals in the 2mass Redshift Survey (2mrs) using high-quality Hi widths and 2mass photometry. Compared with previous peculiar-velocity surveys, the 2mtf survey provides more accurate width measurements and more uniform sky coverage, combining observations with the Green Bank, Arecibo, and Parkes telescopes. With this new redshift-independent distance database, we will significantly improve our understanding of the mass distribution in the local Universe.
We present a new ground-based technique to detect or follow-up long-period, potentially habitable exoplanets via precise relative astrometry of host stars using Multi-Conjugate Adaptive Optics (MCAO) on 8 meter telescopes equipped with diffractive masks. MCAO improves relative astrometry both by cancellation of high-altitude atmospheric layers, which induce dynamic focal-plane distortions, and the improvement of centroiding precision with sharper PSFs. However, mass determination of habitable exoplanets requires multi-year reference grid stability of ~1–10 μas or nanometer-level stability on the long-term average of out-of-pupil phase errors, which is difficult to achieve with MCAO (e.g., Meyer et al. 2011). The diffractive pupil technique calibrates dynamic distortion via extended diffraction spikes generated by a dotted primary mirror, which are referenced against a grid of background stars (Guyon et al. 2012). The diffractive grid provides three benefits to relative astrometry: (1) increased dynamic range, permitting observation of V < 10 stars without saturation; (2) calibration of dynamic distortion; and (3) a spectrum of the target star, which can be used to calibrate the magnitude of differential atmospheric refraction to the microarcsecond level. A diffractive 8-meter telescope with diffraction-limited MCAO in K-band reaches < 3–5 μas relative astrometric error per coordinate perpendicular to the zenith vector in one hour on a bright target star in fields of moderate stellar density (~10–40 stars arcmin−2). We present preliminary on-sky results of a test of the diffractive mask on the Nickel telescope at Lick Observatory.
Antarctic astronomical site-testing has been conducted using autonomous self-powered observatories for more than a decade (the AASTO at South Pole, the AASTINO at Dome C, and PLATO at Dome A/Dome F). More recently autonomous (PLATO) observatories have been developed and deployed to support small-scale scientific instruments, such as HEAT, a 0.6 m aperture terahertz telescope at Ridge A, and AST3, a 0.5 m optical telescope array at Dome A. This paper reviews the evolution of autonomous Antarctic astronomical observatories, and discusses the requirements and implications for observatories that will be needed for future larger-scale facilities.
The IAU Office of Astronomy for Development (OAD)†, established in March 2011 as part of the implementation of the IAU Strategic Plan, is currently located in South Africa and serves as a global coordinating centre for astronomy-for-development activities. In terms of structure the OAD is required to establish regional nodes (similar offices in different parts of the world which focus on a particular geographic or cultural region) and three task forces: (i) Astronomy for Universities and Research, (ii) Astronomy for Children and Schools, and (iii) Astronomy for the Public. This paper will describe the progress of the OAD towards the realisation of the vision ‘Astronomy for a better world’.