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We present sipgi , a spectroscopic pipeline to reduce optical/near-infrared data from slit-based spectrographs. sipgi is a complete spectroscopic data reduction environment, which retains the high level of flexibility and accuracy typical of the standard 'by-hand' reduction methods but is characterized by a significantly higher level of efficiency. This is obtained by exploiting three main concepts: (i) the instrument model: at the core of the data reduction is an analytic description of the main calibration relations (e.g. spectra location and wavelength calibration) that can be easily checked and adjusted on data using a graphical tool; (ii) a built-in data organizer that classifies the data, together with a graphical interface that helps in providing the recipes with the correct input; (iii) the design and flexibility of the reduction recipes: The number of tasks required to perform a complete reduction is minimized, while preserving the possibility of verifying the accuracy of the main stages of data-reduction process with provided tools. The current version of sipgi manages data from the MODS and LUCI spectrographs mounted at the Large Binocular Telescope, and it is our plan to extend sipgi to support other through-slit spectrographs. Meanwhile, to allow using the same approach based on the instrument model with other instruments, we have developed SpectraPy , a spectrograph-independent python library working on through-slit spectra. In its current version, SpectraPy produces two-dimensional wavelength-calibrated spectra corrected by instrument distortions. The current release of sipgi and its documentation can be downloaded from http://pandora.lambrate.inaf.it/sipgi/ , while SpectraPy can be found at http://pandora.lambrate.inaf.it/SpectraPy/. [ABSTRACT FROM AUTHOR]

Using Large Binocular Telescope deep imaging data from the Smallest Scale of Hierarchy Survey (SSH) and archival Hubble Space Telescope data, we reveal the presence of two elongated stellar features contiguous to a bar-like stellar structure in the inner regions of the dwarf irregular galaxy NGC 3741. These structures are dominated by stars younger than a few hundred Myr and collectively are about twice as extended as the old stellar component. These properties are very unusual for dwarf galaxies in the nearby Universe and difficult to explain by hydro-dynamical simulations. From the analysis of archival 21-cm observations, we find that the young stellar 'bar' coincides with an H  i high-density region proposed by previous studies to be a purely gaseous bar; we furthermore confirm radial motions of a few km s−1, compatible with an inflow/outflow, and derive a steeply rising rotation curve and high H  i surface density at the centre, indicating a very concentrated mass distribution. We propose that the peculiar properties of the stellar and gaseous components of NGC 3741 may be explained by a recent merger or ongoing gas accretion from the intergalactic medium, which caused gas inflows towards the galaxy centre and triggered star formation a few hundred Myr ago. This event may explain the young and extended stellar features, the bar-like structure, the very extended H  i disc and the central H  i spiral arms. The high central H  i density and the steeply rising rotation curve suggest that NGC 3741 may be the progenitor or the descendant of a starburst dwarf. [ABSTRACT FROM AUTHOR]

We present results of time-series analysis of the first year of the Fairall 9 intensive disc-reverberation campaign. We used Swift and the Las Cumbres Observatory global telescope network to continuously monitor Fairall 9 from X-rays to near-infrared at a daily to subdaily cadence. The cross-correlation function between bands provides evidence for a lag spectrum consistent with the τ  ∝  λ 4/3 scaling expected for an optically thick, geometrically thin blackbody accretion disc. Decomposing the flux into constant and variable components, the variable component's spectral energy distribution is slightly steeper than the standard accretion disc prediction. We find evidence at the Balmer edge in both the lag and flux spectra for an additional bound-free continuum contribution that may arise from reprocessing in the broad-line region. The inferred driving light curve suggests two distinct components, a rapidly variable (<4 d) component arising from X-ray reprocessing, and a more slowly varying (>100 d) component with an opposite lag to the reverberation signal. [ABSTRACT FROM AUTHOR]

We report on the detection of a blueshifted Fe K absorption feature in two consecutive XMM–Newton   observations of the luminous blue quasar Ton 28, at the 4σ cumulative significance. The rest energy of 9.2 keV implies the presence of an accretion disc wind with bulk outflow velocity of ∼0.28 c, while the kinetic power is most likely a few per cent of the quasar luminosity. Remarkably, Ton 28 had been specifically selected as an optimal target to reveal an ultra-fast X-ray wind based on its total luminosity (L bol > 1046 erg s−1) and [O  iii ] λ5007 Å equivalent width (EW < 6 Å), suggestive of high accretion rate and low inclination, respectively. Other peculiar optical/UV emission-line properties include narrow Hβ, strong Fe  ii , and blueshifted C  iv  . These are key parameters in the Eigenvector 1 formalism, and are frequently found in active galaxies with ongoing accretion disc winds, hinting at a common physical explanation. Provided that the effectiveness of our selection method is confirmed with similar sources, this result could represent the first step towards the characterization of black hole winds through multiwavelength indicators in the absence of high-quality X-ray spectra. [ABSTRACT FROM AUTHOR]