Jagiellonian University

About: Jagiellonian University is a education organization based out in Krakow, Poland. It is known for research contribution in the topics: Population & Catalysis. The organization has 17438 authors who have published 44092 publications receiving 862633 citations. The organization is also known as: Academia Cracoviensis & Akademia Krakowska.

The Structure and Emission Model of the Relativistic Jet in the Quasar 3C 279 Inferred from Radio to High-energy γ-Ray Observations in 2008-2010

Abstract: We present time-resolved broadband observations of the quasar 3C 279 obtained from multi-wavelength campaigns conducted during the first two years of the Fermi Gamma-ray Space Telescope mission. While investigating the previously reported γ-ray/optical flare accompanied by a change in optical polarization, we found that the optical emission appears to be delayed with respect to the γ-ray emission by about 10 days. X-ray observations reveal a pair of "isolated" flares separated by ~90 days, with only weak γ-ray/optical counterparts. The spectral structure measured by Spitzer reveals a synchrotron component peaking in the mid-infrared band with a sharp break at the far-infrared band during the γ-ray flare, while the peak appears in the millimeter (mm)/submillimeter (sub-mm) band in the low state. Selected spectral energy distributions are fitted with leptonic models including Comptonization of external radiation produced in a dusty torus or the broad-line region. Adopting the interpretation of the polarization swing involving propagation of the emitting region along a curved trajectory, we can explain the evolution of the broadband spectra during the γ-ray flaring event by a shift of its location from ~1 pc to ~4 pc from the central black hole. On the other hand, if the γ-ray flare is generated instead at sub-pc distance from the central black hole, the far-infrared break can be explained by synchrotron self-absorption. We also model the low spectral state, dominated by the mm/sub-mm peaking synchrotron component, and suggest that the corresponding inverse-Compton component explains the steady X-ray emission.

A spectral decomposition of the variable optical, ultraviolet and X-ray continuum of NGC 5548

Abstract: We present an analysis and decomposition of the broad-band optical/UV/X-ray/γ-ray spectrum of the Seyfert 1 galaxy NGC 5548. The spectrum consists of an average of simultaneous optical/IUE/Ginga observations accompanied by ROSATCGRO/OSSE data from non-simultaneous observations. We show that the overall optical/UV/X-ray/γ-ray spectrum can be deconvolved into three basic continuum components: a cool multitemperature blackbody, a hard thermal Comptonized component and an EUV/soft X-ray component well described by a thermal Comptonization continuum. Assuming that the optical/IUE spectrum comes from a cold disc, the maximum disc temperature is very well constrained by the data to be kTdisc = 3.2+0.2−0.2 eV. This rules out models explaining the soft excess as a far tail of the disc spectrum. We show that the soft excess inferred by the data requires a separate continuum component, which is consistent with thermal Comptonization in optically thick (τ ∼ 30), warm (∼0.3 keV) plasma. This Comptonization component contains a significant fraction of the source energy. The plasma parameters of the hard continuum (τ ∼ 2, kTHC ∼ 50 keV) are consistent with those suggested for the average spectrum of Seyferts. On the basis of the broad-band spectral model, we also re-analyse the simultaneous IUE/Ginga campaign. We find that the fluxes in all three continuum components are positively correlated. The total flux emitted in the hard component is positively correlated with both the spectral index and the solid angle of cold matter seen by the hot source. Such a correlation suggests that the variability mechanism is related to changes in the geometry of the continuum-emitting regions, and an excess in the amount of reflection requires deviations from a simple plane disc picture. The variations in the hard spectral index can then be explained by increased cooling of the hot plasma caused by the increased number of seed photons. We suggest that the geometry variations may be related to a transition region between a cold and a hot disc.

Catalysts based on amino acids for asymmetric reactions in water.

Abstract: Asymmetric organometallic and organocatalytic processes in aqueous systems are currently of great interest A few years ago, only a few practitioners studied the subject; now organic reactions in water have become one of the most exciting research areas The quest to identify water-compatible catalysts has evoked an intense search for new possibilities Following nature's lead, the application of amino acids as sources of chiral information seems particularly promising for aqueous systems Herein we provide an overview of very recent advances in the area of asymmetric catalysis in water with amino acids and their derivatives as effective catalysts or essential components of catalysts

Badenian evolution of the Central Paratethys Sea: paleogeography, climate and eustatic sea level changes

Abstract: The Miocene Central Paratethys Sea covered wide areas of the Pannonian Basin System, bordered by the mountain chains of the Alps, Carpathians and Dinarides. The epicontinental sea spread not only in the back-arc basin area, but flooded even the Alpine-Carpathian Foredeep, situated along the front of gradually uplifting mountains. The Early Badenian (early Langhian) transgressions from the Mediterranean toward the Central Paratethys realm, via Slovenia and northern Croatia (Transtethyan Trench Corridor or Trans Dinaride Corridor) flooded the Pannonian Basin and continued along straits in the Carpathian Chain into the Carpathian Foredeep. The isolation of eastern parts of the Central Paratethys at the end of this period (late Langhian) resulted in the "Middle Badenian" salinity crisis. Thick evaporite sediments, above all halite and gypsum were deposited in the Transcarpathian Basin, Transylvanian Basin and Carpathian Foredeep. During the Late Badenian (early Serravallian), the latest full marine flooding covered the whole back-arc basin and a great part of the foredeep. The main problem is to create a model of sea connections during that time, because some authors consider the western Transtethyan Trench Corridor (Trans Dinaride Corridor) closed and there is no evidence to prove a supposed strait towards the Eastern Mediterranean. A proposed possibility is a connection towards the Konkian Sea of the Eastern Paratethys. The Badenian climate of the Central Paratethys realm can be characterized as fairly uniform, reflecting the stable subtropical conditions of the Miocene Climatic Optimum. No considerable changes in terrestrial ecosystems were documented. Nevertheless, evolution of steep landscape associated with rapid uplift of the East Alpine and Western Carpathian mountain chains (including high stratovolcanoes) caused development of vertical zonation of dry land and consequently close occurrence of different vegetation zones in a relatively small distance during this time. In the Central Paratethys Sea a slight N-S climatic gradient seems to be expressed already from the Early Badenian, but a biogeographic differentiation between basins in the North and South starts to become more prominent first during the Late Badenian, when a moderate cooling of the seawater can also be documented. The Late Badenian sea-level highstand coincides with the appearance of stress factors such as stratification of the water column and hypoxic conditions at the basin bottom in the whole area. Taking into account all bioevents and changes of paleogeography in the Central Paratethys realm, we can very roughly correlate the Early (and "Middle") Badenian with the eustatic sea-level changes of TB 2.3, TB 2.4 or Bur5/Lan1, Lan2/Ser1 and the Late Badenian with TB 2.5 or Ser2 cycles (sensu Haq et al. 1988; Hardenbol et al. 1998). Generally, we can assign the Early Badenian transgressions to be controlled by both, tectonics (induced mainly by back-arc basin REVIEW