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Antichi J.,Istituto Nazionale di Astrofisica Osservatorio Astrofisico di Arcetri | Munari M.,Istituto Nazionale di Astrofisica Osservatorio Astrofisico di Catania | Magrin D.,Istituto Nazionale di Astrofisica Osservatorio Astronomico di Padua | Riccardi A.,Istituto Nazionale di Astrofisica Osservatorio Astrofisico di Arcetri
Journal of Astronomical Telescopes, Instruments, and Systems | Year: 2016

Following the unprecedented results in terms of performances delivered by the first light adaptive optics system at the Large Binocular Telescope, there has been a wide-spread and increasing interest on the pyramid wavefront sensor (PWFS), which is the key component, together with the adaptive secondary mirror, of the adaptive optics (AO) module. Currently, there is no straightforward way to model a PWFS in standard sequential ray-tracing software. Common modeling strategies tend to be user-specific and, in general, are unsatisfactory for general applications. To address this problem, we have developed an approach to PWFS modeling based on user-defined surface (UDS), whose properties reside in a specific code written in C language, for the ray-tracing software ZEMAX™. With our approach, the pyramid optical component is implemented as a standard surface in ZEMAX™, exploiting its dynamic link library (DLL) conversion then greatly simplifying ray tracing and analysis. We have utilized the pyramid UDS DLL surface - referred to as pyramidal acronyms may be too risky (PAM2R) - in order to design the current PWFS-based AO system for the Giant Magellan Telescope, evaluating tolerances, with particular attention to the angular sensitivities, by means of sequential ray-tracing tools only, thus verifying PAM2R reliability and robustness. This work indicates that PAM2R makes the design of PWFS as simple as that of other optical standard components. This is particularly suitable with the advent of the extremely large telescopes era for which complexity is definitely one of the main challenges. © 2016 Society of Photo-Optical Instrumentation Engineers (SPIE).

Gruppioni C.,Istituto Nazionale di Astrofisica Osservatorio Astronomico di Bologna | Berta S.,Max Planck Institute for Extraterrestrial Physics | Spinoglio L.,Istituto di Astrofisica Spaziale e Fisica Cosmica | Pereira-Santaella M.,CSIC - National Institute of Aerospace Technology | And 9 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2016

We present new estimates of AGN accretion and star formation (SF) luminosity in galaxies obtained for the local 12 μm sample of Seyfert galaxies (12MGS), by performing a detailed broad-band spectral energy distribution (SED) decomposition including the emission of stars, dust heated by SF and a possible AGN dusty torus. Thanks to the availability of data from the X-rays to the sub-millimetre, we constrain and test the contribution of the stellar, AGN and SF components to the SEDs. The availability of Spitzer-InfraRed Spectrograph (IRS) low-resolution mid-infrared (mid-IR) spectra is crucial to constrain the dusty torus component at its peak wavelengths. The results of SED fitting are also tested against the available information in other bands: the reconstructed AGN bolometric luminosity is compared to those derived from X-rays and from the high excitation IR lines tracing AGN activity like [Ne v] and [O iv]. The IR luminosity due to SF and the intrinsic AGN bolometric luminosity are shown to be strongly related to the IR line luminosity. Variations of these relations with different AGN fractions are investigated, showing that the relation dispersions are mainly due to different AGN relative contribution within the galaxy. Extrapolating these local relations between line and SF or AGN luminosities to higher redshifts, by means of recent Herschel galaxy evolution results, we then obtain mid-and far-IR line luminosity functions useful to estimate how many star-forming galaxies and AGN we expect to detect in the different lines at different redshifts and luminosities with future IR facilities (e.g. JWST, SPICA). © 2016 The Authors.

Forster Schreiber N.M.,Max Planck Institute for Extraterrestrial Physics | Genzel R.,Max Planck Institute for Extraterrestrial Physics | Genzel R.,University of California at Berkeley | Newman S.F.,University of California at Berkeley | And 30 more authors.
Astrophysical Journal | Year: 2014

We report the detection of ubiquitous powerful nuclear outflows in massive (≥1011 M ) z 2 star-forming galaxies (SFGs), which are plausibly driven by an active galactic nucleus (AGN). The sample consists of the eight most massive SFGs from our SINS/zC-SINF survey of galaxy kinematics with the imaging spectrometer SINFONI, six of which have sensitive high-resolution adaptive optics-assisted observations. All of the objects are disks hosting a significant stellar bulge. The spectra in their central regions exhibit a broad component in Hα and forbidden [N II] and [S II] line emission, with typical velocity FWHM 1500 km s-1, [N II]/Hα ratio 0.6, and intrinsic extent of 2-3 kpc. These properties are consistent with warm ionized gas outflows associated with Type 2 AGN, the presence of which is confirmed via independent diagnostics in half the galaxies. The data imply a median ionized gas mass outflow rate of 60 M yr-1 and mass loading of 3. At larger radii, a weaker broad component is detected but with lower FWHM 485 km s -1 and [N II]/Hα 0.35, characteristic for star formation-driven outflows as found in the lower-mass SINS/zC-SINF galaxies. The high inferred mass outflow rates and frequent occurrence suggest that the nuclear outflows efficiently expel gas out of the centers of the galaxies with high duty cycles and may thus contribute to the process of star formation quenching in massive galaxies. Larger samples at high masses will be crucial in confirming the importance and energetics of the nuclear outflow phenomenon and its connection to AGN activity and bulge growth. © 2014. The American Astronomical Society. All rights reserved..

Milone A.P.,Australian National University | Marino A.F.,Australian National University | Bedin L.R.,Istituto Nazionale di Astrofisica Osservatorio Astronomico di Padua | Piotto G.,Istituto Nazionale di Astrofisica Osservatorio Astronomico di Padua | And 17 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2014

The M 4 Core Project with HST is designed to exploit the Hubble Space Telescope (HST) to investigate the central regions of M 4, the Globular Cluster closest to the Sun. In this paper we combine optical and near-infrared photometry to study multiple stellar populations in M4.We detected two sequences of M-dwarfs containing ~38 per cent (MSI) and ~62 per cent (MSII) of MS stars below the main-sequence (MS) knee. We compare our observations with those of NGC 2808, which is the only other GCs where multiple MSs of very low-mass stars have been studied to date. We calculate synthetic spectra for M-dwarfs, assuming the chemical composition mixture inferred from spectroscopic studies of stellar populations along the red giant branch, and different helium abundances, and we compare predicted and observed colours. Observations are consistent with two populations, one with primordial abundance and another with enhanced nitrogen and depleted oxygen. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Bedin L.R.,Istituto Nazionale di Astrofisica Osservatorio Astronomico di Padua | Anderson J.,US Space Telescope Science Institute | Heggie D.C.,University of Edinburgh | Piotto G.,Istituto Nazionale di Astrofisica Osservatorio Astronomico di Padua | And 21 more authors.
Astronomische Nachrichten | Year: 2013

We present an overview of the ongoing Hubble Space Telescope large program GO-12911. The program is focused on the core of M 4, the nearest Galactic globular cluster, and the observations are designed to constrain the number of binaries with massive companions (black holes, neutron stars, or white dwarfs) by measuring the "wobble" of the luminous (mainsequence) companion around the center of mass of the pair, with an astrometric precision of ∼50 μas. The high spatial resolution and stable medium-band PSFs of WFC3/UVIS will make these measurements possible. In this work we describe (i) the motivation behind this study, (ii) our observing strategy, (iii) the many other investigations enabled by this unique data set, and which of those our team is conducting, and (iv) a preliminary reduction of the first-epoch dataset collected on 2012 October 10. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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