G Trinchieri

University of Birmingham, Birmingham, England, United Kingdom

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Publications (395)2095.91 Total impact

  • Source
    G. Trinchieri · R. Rampazzo · P. Mazzei · A. Marino · A. Wolter
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    ABSTRACT: We report here the results from the X-ray observations of 12 early-type galaxies (ETGs) observed with Swift and XMM-Newton, originally selected from a sample of galaxies with Spitzer and/or GALEX data. With the combined analysis of new X-ray and optical-UV observations and of previously available data from archives, we aim at investigating the relation between X-ray luminosity and evolutionary phases of ETGs. We will interpret the results with the additional aid of smoothed particle hydrodynamics chemo-photometric simulations. All galaxies have been detected in the X-ray band, with luminosities Lx > 1039 erg s−1. X-ray emitting gas has been detected in about half of the sample, with luminosities from ≥1039 to 1040 erg s−1. UVOT images show a variety of morphologies, from absence of peculiar features relative to optical wavelengths typical of red and dead early-types, to well defined almost circular rings clearly emerging in the U band, to more spectacular and complex features connected to recent or even ongoing star formation (SF). We find little evidence of any influence of the SF activity on their global X-ray properties, and in particular, on the luminosity-weighted age of the system, usually estimated in the nuclear region. However, with the present data we cannot exclude that such a relation exists on smaller scales, related to the specific sites where we see evidence of newly formed stars, such as outer rings and arcs and peculiar features observed in UV images.
    Monthly Notices of the Royal Astronomical Society 03/2015; 449(3):3021-3042. DOI:10.1093/mnras/stv466 · 5.23 Impact Factor
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    S. Andreon · A. B. Newman · G. Trinchieri · A. Raichoor · R. S. Ellis · T. Treu
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    ABSTRACT: Using deep two-color near-infrared HST imaging and unbiased grism spectroscopy we present a detailed study of the z=1.803 JKCS041 cluster. Uniquely, for a high redshift cluster, we confirm a mass of $\log M=14.2$ in solar units using three different techniques based on the X-ray temperature, the X-ray luminosity and the cluster richness. JKCS041 is thus a progenitor of a local system like the Coma cluster. Our rich dataset and the abundant population of 14 spectroscopically-confirmed red sequence galaxies allows us to explore the past star formation history of this system in unprecedented detail. Remarkably, we find a prominent red sequence down to stellar masses as low as $\log M=9.8$, corresponding to a mass range of 2 dex. These quiescent galaxies are concentrated around the cluster center with a core radius of 330 kpc. Blue members are few and avoid the cluster center. In JKCS041 quenching was therefore largely completed by a look-back time of 10 Gyr and we can constrain the epoch at which this occurred via spectroscopic age-dating of the individual galaxies. Most galaxies were quenched about 1.1 Gyr prior to the epoch of observation. The less massive quiescent galaxies are somewhat younger, corresponding to a decrease in age of 650 Myr per mass dex, but the scatter in age at fixed mass is only 380 Myr (at $\log M=11$). The size-mass relation of quiescent galaxies in JKCS041 is consistent with that observed for local clusters within our uncertainties. Comparing our data on JKCS041 with 41 clusters at lower redshift, we find that the form of the mass function of red sequence galaxies has hardly evolved in the past 10 Gyr, both in terms of its faint end slope and characteristic mass. Despite observing JKCS041 soon after its quenching and the three fold expected increase in mass in the next 10 Gyr, it is already remarkably similar to present-day clusters.
    Astronomy and Astrophysics 11/2013; 565. DOI:10.1051/0004-6361/201323077 · 4.48 Impact Factor
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    ABSTRACT: HST WFPC2 data for NGC 4261 were obtained with the F450W, F606W and F814W filters (roughly corresponding to the B, V and I bands, respectively; see WFPC2 Instrument Handbook, version 10.0, table 3.1). (1 data file).
  • E. Memola · G. Trinchieri · A. Wolter · P. Focardi · B. Kelm
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    ABSTRACT: Aims. We investigate the X-ray properties of four isolated elliptical galaxies, selected from the Updated Zwicky Catalog according to strict isolation criteria. Isolated galaxies are not influenced by the group/cluster environment, and their X-ray emission can be studied independently of the often overwhelming contribution of the hot intergalactic medium. They are therefore suited to studying the X-ray characteristics relative to their intrinsic properties. Methods. We analyzed our own XMM-Newton and archival Chandra data in detail for three objects, and derived, when possible, the spatial and spectral characteristics of each source. An upper limit for the fourth one was obtained from archival ASCA data. We compared their characteristics with those of other 23 isolated objects for which X-ray and optical data are available in the literature. We explored possible theoretical explanations to interpret our results. Results. In spite of our attempt to select very homogeneous objects, both in terms of optical properties and environmental characteristics, we find a wide range in X-ray luminosities and LX/LB ratios for the four objects: two of them show a hot gaseous halo, whereas no gas is detected in the other two, to a factor> 10 in luminosity. In fact, we find a large spread in the LX/LB for all galaxies considered, suggesting that the presence of hot gas is not easily related to the optical luminosity or to the mass, even in isolated systems. Younger objects tend to be less luminous in X-rays than older systems. However, it appears that older objects could span a wide range in luminosities. Key words. X-rays: galaxies – Galaxies: elliptical and lenticular, cD 1.
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    ABSTRACT: c ○ Springer-Verlag •••• Abstract Shell galaxies are considered the debris of recent accretion/merging episodes. Their high frequency in low density environments suggest that such episodes could drive the secular evolution for at least some fraction of the early-type galaxy population. We present here the preliminary results of ultraviolet and X-ray data for a sample of three shell galaxies, namely NGC 474, NGC 7070A and ESO 2400100. The Far UV morphology and photometry are derived using the observations obtained with the Galaxy Evolution Explorer and the XMM-Newton Optical Monitor. We aim at investigating the rejuvenation processes in the stellar population using the UV information as well as at gaining information about the possible evolution with time of the X-ray emission due interaction/merging processes. Keywords Ultraviolet: galaxies — X-ray:galaxies —
  • G. Trinchieri
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    ABSTRACT: The X-ray band provides a very powerful and unique way to explore the hot phase of the ISM in external galaxies. This phase has been known to exist in galaxies since the early Einstein observations, but only with recent detailed observations of objects in the local universe are we beginning to study it in detail and appreciate the importance of the hot ISM as a vehicle of chemical enrichment in different astrophysical environments. This knowledge can then be used to understand the properties of galaxies at the epoch of formation and their subsequent evolution, both in the field and in clusters.
    EAS Publications Series 09/2012; 56:231-238. DOI:10.1051/eas/1256037
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    G. Trinchieri · A. Marino · P. Mazzei · R. Rampazzo · A. Wolter
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    ABSTRACT: [Abridged] NGC 5238 and NGC 4756 are the brightest unperturbed elliptical galaxies in their respective loose groups. In the present study we aim at characterizing the properties of the hot gas in the halos of the brightest members and in the environment. In NGC 4756 we are also interested in the properties of a substructure identified to the SW and the region connecting the two structures, to search for a physical connection between the two. However, we have to take into account the fact that the group is projected against the bright, X-ray emitting cluster A1361, which heavily contaminates and confuses the emission from the foreground structure. We present a careful analysis of XMM-Newton data of the groups to separate different components. We also present a re-evaluation of the dynamical properties of the systems and . SPH simulations to interpret the results. We find that the X-ray source associated with NGC 4756 indeed sits on top of extended emission from the background cluster A1361, but can be relatively well distinguished from it as a significant excess over it out to r\sim150"\ (~40 kpc). NGC 4756 has an X-ray luminosity of ~10^41 erg/s due to hot gas, with an average temperature of kT\sim0.7 keV. We measure a faint diffuse emission also in the region of the subclump to the SW, but more interestingly, we detect gas between the two structures, indicating a possible physical connection. The X-ray emission from NGC 5328 is clearly peaked on the galaxy, also at 10^41 erg/s, and extends to r\sim110 kpc. Simulations provide an excellent reproduction of the SED and the global properties of both galaxies, which are caught at two different epochs of the same evolutionary process, with NGC 5328 ~2.5 Gyr younger than NGC 4756.
    Astronomy and Astrophysics 08/2012; 545. DOI:10.1051/0004-6361/201219775 · 4.48 Impact Factor
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    ABSTRACT: We report the spectral and temporal variability properties of 18 candidate transient and potential transient (TC and PTC) sources detected in deep multi-epoch Chandra observation of the nearby elliptical galaxies, NGC 3379, NGC 4278 and NGC 4697. Only one source can be identified with a background counterpart, leaving 17 TCs + PTCs in the galaxies. Of these, 14 are in the galaxy field, supporting the theoretical picture that the majority of field X-ray binaries (XRBs) will exhibit transient accretion for >75% of their lifetime. Three sources are coincident with globular clusters (GCs), including two high-luminosity candidate black hole (BH) XRBs, with Lx=5.4E38 erg/s, and Lx=2.8E39 erg/s, respectively. The spectra, luminosities and temporal behavior of these 17 sources suggest that the transient population is heterogeneous, including neutron star (NS) and BH XRBs in both normal and high-rate accretion modes, and super soft sources containing white dwarf binaries. Our TC and PTC detections are noticeably fewer that the number expected from the populations synthesis (PS) models of Fragos et al. (2009), tailored to our new Chandra pointings of NGC 4278. We attribute this discrepancy to the PS assumption that the transient population is composed of NS XRBs, as well as differences between the statistical analysis and error estimates used in the model and our observations.
    The Astrophysical Journal 06/2012; 755(2). DOI:10.1088/0004-637X/755/2/162 · 6.28 Impact Factor
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    S. Tamburri · G. Trinchieri · A. Wolter · J. Sulentic · A. Durbala · M. Rosado
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    ABSTRACT: Seyfert's Sextet (a.k.a HCG 79) is one of the most compact and isolated galaxy groups in the local Universe. It shows a prominent diffuse light component that accounts for ~50% of the total observed light. This likely indicates that the group is in an advanced evolutionary phase, which would predict a significant hot gaseous component. Previous X-ray observations had suggested a low luminosity for this system, but with large uncertainties and poor resolution. We present the results from a deep (70 ks), high resolution Chandra observation of Seyfert's Sextet, requested with the aim of separating the X-ray emission associated with the individual galaxies from that of a more extended inter-galactic component. We discuss the spatial and spectral characteristics of this group we derive with those of a few similar systems also studied in the X-ray band. The high resolution X-ray image indicates that the majority of the detected emission does not arise in the compact group but is concentrated towards the NW and corresponds to what appears to be a background galaxy cluster. The emission from the group alone has a total luminosity of ~1x10^40 erg/s in the (0.5-5) keV band. Most of the luminosity can be attributed to the individual sources in the galaxies, and only ~2x10^39 erg/s is due to a gaseous component. However, we find that this component is also mostly associated with the individual galaxies of the Sextet, leaving little or no residual in a truly IGM component. The extremely low luminosity of the diffuse emission in Seyfert's Sextet might be related to its small total mass.
    Astronomy and Astrophysics 04/2012; 541. DOI:10.1051/0004-6361/201118758 · 4.48 Impact Factor
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    ABSTRACT: We present an analysis of the globular cluster (GC) population of the elliptical galaxy NGC 4261 based on Hubble Space Telescope Wide Field Planetary Camera 2 data in the B, V and I bands. We study the spatial distribution of the GCs in order to probe the anisotropy in the azimuthal distribution of the discrete X-ray sources in the galaxy revealed by Chandra images. The luminosity function of our GC sample (complete at the 90 per cent level for mV= 23.8 mag) peaks at mV= 25.1? mag, which corresponds to a distance consistent with previous measurements. The colour distribution can be interpreted as being the superposition of a blue and red GC component with average colours V-I= 1.01? mag and 1.27? mag, respectively. This is consistent with a bimodal colour distribution typical of elliptical galaxies. The red GC's radial profile is steeper than that of the galaxy surface brightness, while the profile of the blue subpopulation looks more consistent with it. The most striking finding is the significant asymmetry in the azimuthal distribution of the GC population about a north-east-south-west (NE-SW) direction. The lack of any obvious feature in the morphology of the galaxy suggests that the asymmetry could be the result of an interaction or a merger.
    Monthly Notices of the Royal Astronomical Society 04/2012; 421(4):2872-2887. DOI:10.1111/j.1365-2966.2012.20514.x · 5.23 Impact Factor
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    S. Andreon · G Trinchieri · F. Pizzolato
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    ABSTRACT: The evolution of the properties of the hot gas that fills the potential well of galaxy clusters is poorly known, since models are unable to give robust predictions and observations lack a sufficient redshift leverage and are affected by selection effects. Here, with just two high redshift, z approx 1.8, clusters avoiding selection biases, we obtain a significant extension of the redshift range and we begin to constrain the possible evolution of the X-ray luminosity vs temperature relation. The two clusters, JKC041 at z=2.2 and ISCSJ1438+3414 at z=1.41, are respectively the most distant cluster overall, and the second most distant that can be used for studying scaling relations. Their location in the X-ray luminosity vs temperature plane, with an X-ray luminosity 5 times lower than expected, suggests at the 95 % confidence that the evolution of the intracluster medium has not been self-similar in the last three quarters of the Universe age. Our conclusion is reinforced by data on a third, X-ray selected, high redshift cluster, too faint for its temperature when compared to a sample of similarly selected objects. Our data suggest that non-gravitational effects, such as the baryon physics, influence the evolution of galaxy cluster. Precise knowledge of evolution is central for using galaxy clusters as cosmological probes in planned X-ray surveys such as WFXT or JDEM. Comment: MNRAS, in press. Fig 1 degraded to fit arxiv size constraints
    Monthly Notices of the Royal Astronomical Society 12/2010; 412(4). DOI:10.1111/j.1365-2966.2010.18062.x · 5.23 Impact Factor
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    ABSTRACT: We report a detailed spectral analysis of the population of low-mass X-ray binaries (LMXBs) detected in the elliptical galaxy NGC 4278 with Chandra. Seven luminous sources were studied individually, four in globular clusters (GCs) and three in the stellar field. The range of (0.3-8 keV) L X for these sources is ~(3-8) × 1038 erg s–1, suggesting that they may be black hole binaries (BHBs). Fitting the data with either single thermal accretion disk or power-law (PO) models results in best-fit temperatures of ~0.7-1.7 keV and Γ ~ 1.2-2.0, consistent with those measured in Galactic BHBs. Comparison of our results with simulations allows us to discriminate between disk and power-law-dominated emission, pointing to spectral/luminosity variability, reminiscent of Galactic BHBs. The BH masses derived from a comparison of our spectral results with the L X ~ T 4 in relation of Galactic BHBs are in the 5-15 M ☉ range, as observed in the Milky Way. The analysis of joint spectra of sources selected in three luminosity ranges (L X ≥ 1.5 × 1038 erg s–1, 6 × 1037ergs–1 ≤ L X < 1.5 × 1038 erg s–1, and L X < 6 × 1037 erg s–1) suggests that while the high-luminosity sources have prominent thermal disk emission components, power-law components are likely to be important in the mid- and low-luminosity spectra. Comparing low-luminosity average spectra, we find a relatively larger N H in the GC spectrum; we speculate that this may point to either a metallicity effect or to intrinsic physical differences between field and GC accreting binaries. Analysis of average sample properties uncovers a previously unreported L X-R G correlation (where R G is the galactocentric radius) in the GC-LMXB sample, implying richer LMXB populations in more central GCs. No such trend is seen in the field LMXB sample. We can exclude that the GC L X-R G correlation is the by-product of a luminosity effect and suggest that it may be related to the presence of more compact GCs at smaller galactocentric radii, fostering more efficient binary formation.
    The Astrophysical Journal 12/2010; 725(2):1824. DOI:10.1088/0004-637X/725/2/1824 · 6.28 Impact Factor
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    G Trinchieri · A. Wolter
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    ABSTRACT: Galaxies are essential building blocks in the Universe. However they are faint and complex X-ray sources and require high performance instrumentation to be properly studied. Yet they are fundamental for our understanding of the Universe, and a detailed knowledge of the local structures is mandatory to explain the deep and far Universe. We make a few examples, and discuss how well suited WFXT is to address this issue. Comment: 6 pages, 4 figures; to appear in the Proceedings of "The Wide Field X-ray Telescope Workshop", held in Bologna, Italy, Nov. 25-26 2009, published by Memorie della Societ\`a Astronomica Italiana 2010 (arXiv:1010.5889)
    11/2010;
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    ABSTRACT: The radio source 3C270, hosted by nearby elliptical galaxy NGC4261, is the brightest known example of counterjet X-ray emission from a low-power radio galaxy. We report on the X-ray emission of the jet and counterjet from 130 ks of Chandra data. We argue that the X-ray emission is synchrotron radiation and that the internal properties of the jet and counterjet are remarkably similar. We find a smooth connection in X-ray hardness and X-ray-to-radio ratio between the jet and one of the X-ray components within the core spectrum. We observe wedge-like depressions in diffuse X-ray surface brightness surrounding the jets, and interpret them as regions where an aged population of electrons provides pressure to balance the interstellar medium of NGC4261. About 20 per cent of the mass of the interstellar medium has been displaced by the radio source. Treating 3C270 as a twin-jet system, we find an interesting agreement between the ratio of jet-to-counterjet length in X-rays and that expected if X-rays are observed over the distance that an outflow from the core would have travelled in ~ 6 × 104 yr. X-ray synchrotron loss times are shorter than this, and we suggest that most particle acceleration arises as a result of turbulence and dissipation in a stratified flow. We speculate that an episode of activity in the central engine beginning ~ 6 × 104 yr ago has led to an increased velocity shear. This has enhanced the ability of the jet plasma to accelerate electrons to X-ray-synchrotron-emitting energies, forming the X-ray jet and counterjet that we see today.
    Monthly Notices of the Royal Astronomical Society 10/2010; 408:701-712. DOI:10.1111/j.1365-2966.2010.17162.x · 5.23 Impact Factor
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    ABSTRACT: We report a detailed spectral analysis of the population of low-mass X-ray binaries (LMXBs) detected in the elliptical galaxy NGC~4278 with Chandra. Seven luminous sources were studied individually, four in globular clusters (GCs), and three in the stellar field. The range of (0.3-8 keV) $L_X$ for these sources suggests that they may be black hole binaries (BHBs). Comparison of our results with simulations allows us to discriminate between disk and power-law dominated emission, pointing to spectral/luminosity variability, reminiscent of Galactic BHBs. The BH masses derived from a comparison of our spectral results with the $L_X \sim T^4_{in}$ relation of Galactic BHBs are in the 5-15 $M_{\odot}$ range, as observed in the Milky Way. The analysis of joint spectra of sources selected in three luminosity ranges suggests that while the high luminosity sources have prominent thermal disk emission components, power-law components are likely to be important in the mid and low-luminosity spectra. Comparing low-luminosity average spectra, we find a relatively larger $N_H$ in the GC spectrum; we speculate that this may point to either a metallicity effect, or to intrinsic physical differences between field and GC accreting binaries. Analysis of average sample properties uncover a previously unreported $L_X - R_G$ correlation (where $R_G$ is the galactocentric radius) in the GC-LMXB sample, implying richer LMXB populations in more central GCs. No such trend is seen in the field LMXB sample. We can exclude that the GC $L_X - R_G$ correlation is the by-product of a luminosity effect, and suggest that it may be related to the presence of more compact GCs at smaller galactocentric radii, fostering more efficient binary formation. Comment: Accepted for publication in ApJ
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    ABSTRACT: The X-ray-infrared spectral energy distributions (SEDs) of a sample of X-ray selected AGN at z=0.2-3 are modeled with a nuclear and host component in order to determine the importance of host type, nuclear obscuration, and AGN intrinsic SED in sources of different type and luminosity. Overall, there is a good correspondence between optical obscuration and X-ray absorption. The AGN is X-ray absorbed in type 2 AGN and unabsorbed in type 1 AGN, as expected. We find two types of intrinsic AGN SEDs with different X-ray/mid-infrared luminosity ratios independently of the AGN luminosity and obscuration.
    10/2010;
  • A. Wolter · D. Vergani · G. Trinchieri
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    ABSTRACT: Emission from cold gas is rarely found in ellipticals and is not correlated to the optical luminosity. However, HI is detected in on-going mergers as e.g. the NGC5719/13 pair (Vergani et al. 2007). Dynamical modeling require late-type spiral progenitors (Hibbard et al. 1995), which produced HI-rich tidal tails expected to fall back to the main body of the galaxy in about 3 Gyr. Es formed through merging of spirals might possess a reservoir of cold gas which is otherwise missing. Also the large intrinsic scatter in the X-ray properties of early type galaxies could be due to their different merging histories. Galaxies with distinctive signs of disturbances show a strong deficiency of hot ISM, and merger remnants, like NGC3921 and NGC7252 are under-luminous in X-rays compared with the typical mature E in which these remnants are expected to evolve (for details, see discussion in Memola et al 2009).We are currently studying the hypothesis that the presence of HI is related to a recent merger event and anti-correlated with high X-ray-luminosity gas. If true, this would also help explaining the LX / LK spread in terms of different evolutionary paths. The figure shows that in a sample of isolated ellipticals (Memola et al 2009, Trinchieri, this volume) most of the galaxies for which we have a secure detection of hot X-ray emitting gas have only upper limits in HI, while the objects for which cold gas is present are actually upper limits for the hot gas, hinting at the above hypothesis. However the paucity of data does not allow us to draw conclusions at this time.
    10/2010;
  • G. Trinchieri · A. Wolter · E. Memola · P. Focardi · B. Kelm
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    ABSTRACT: In spite of careful selection of very homogeneous objects, both in terms of optical properties and environmental characteristics, we were unable to significantly reduce the large spread in the Lx vs Lb plane. We confirm that optical luminosities are not clear predictors of the X-ray luminosity in early-type galaxies, even when environmental effects have been minimized by choosing a sample of truly isolated objects.
    10/2010;
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    ABSTRACT: AGN exhibit a variety of spectral energy distributions whose shapes depend on the intrinsic properties of the AGN, the extinction and absorption suffered by the nuclear radiation and the contribution of the host galaxy. Here, the intrinsic AGN spectral energy distributions of a hard X-ray selected sample of AGN from the XMDS are characterized after removing the host contribution and taking into account the effects of obscuration and absorption. We find that the intrinsic AGN spectral energy distributions can differ in their mid-infrared-to-X-ray luminosity ratios.
    07/2010; DOI:10.1063/1.3475317
  • M. Molina · M. Polletta · L. Chiappetti · L. Paioro · G. Trinchieri
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    ABSTRACT: We present the XMM-Newton sample in the Chandra/SWIRE field. We compare the recent XMM (2008-2009) and previous Chandra (2004) observations to identify a sub-sample of variable sources. We find that variability is independent of X-ray absorption and dust obscuration. The analysis of the radio fluxes reveals a significant fraction of radio-weak AGNs and a higher incidence of absorption among radio-loud sources. The source list and multi-wavelength catalogs in the Chandra/SWIRE field can be accessed through an on-line database.
    07/2010; DOI:10.1063/1.3475308

Publication Stats

30k Citations
2,095.91 Total Impact Points

Institutions

  • 2012
    • University of Birmingham
      • School of Physics and Astronomy
      Birmingham, England, United Kingdom
  • 1985–2012
    • Harvard-Smithsonian Center for Astrophysics
      • Smithsonian Astrophysical Observatory
      Cambridge, Massachusetts, United States
    • New York Medical College
      • Department of Microbiology and Immunology
      New York, New York, United States
  • 1991–2010
    • The Astronomical Observatory of Brera
      Merate, Lombardy, Italy
    • European Southern Observatory
      Arching, Bavaria, Germany
  • 2007
    • University of Milan
      Milano, Lombardy, Italy
  • 2004–2005
    • University of Crete
      • Department of Physics
      Retimo, Crete, Greece
  • 2001
    • University of Maryland, College Park
      CGS, Maryland, United States
  • 1976–2001
    • Wistar Institute
      • Melanoma Research Center
      Philadelphia, Pennsylvania, United States
  • 1999
    • Space Telescope Science Institute
      Baltimore, Maryland, United States
  • 1981–1999
    • University of Pennsylvania
      Philadelphia, Pennsylvania, United States
  • 1998
    • William Penn University
      Filadelfia, Pennsylvania, United States
  • 1997
    • Università degli Studi di Perugia
      • Department of Experimental Medicine and Biochemical Sciences
      Perugia, Umbria, Italy
  • 1996–1997
    • Johns Hopkins University
      • Department of Medicine
      Baltimore, MD, United States
    • Uniformed Services University of the Health Sciences
      • Department of Microbiology & Immunology
      Maryland, United States
    • Case Western Reserve University
      Cleveland, Ohio, United States
  • 1993–1997
    • Thomas Jefferson University
      • Department of Microbiology & Immunology
      Philadelphia, PA, United States
    • University of Florence
      • Dipartimento di Medicina Sperimentale e Clinica
      Florence, Tuscany, Italy
  • 1992–1996
    • University of Verona
      • Section of General Pathology
      Verona, Veneto, Italy
  • 1995
    • Molecular and Cellular Biology Program
      Seattle, Washington, United States
    • University of Münster
      • Klinik und Poliklinik für Hautkrankheiten
      Muenster, North Rhine-Westphalia, Germany
    • Infectious Disease Research Institute
      Seattle, Washington, United States
  • 1994
    • National Institute of Allergy and Infectious Diseases
      • Laboratory of Parasitic Diseases (LPD)
      Maryland, United States
    • Chungnam National University
      Daiden, Daejeon, South Korea
    • Palo Alto Institute for Research and Education
      Palo Alto, California, United States
  • 1990–1994
    • The Children's Hospital of Philadelphia
      • Division of Infectious Diseases
      Philadelphia, Pennsylvania, United States
    • INO - Istituto Nazionale di Ottica
      Florens, Tuscany, Italy
    • National Research Council
      Roma, Latium, Italy
  • 1989
    • Metamark Genetics
      Cambridge, Massachusetts, United States
  • 1986
    • Massachusetts Institute of Technology
      Cambridge, Massachusetts, United States
  • 1980
    • Ludwig Institute for Cancer Research
      لا هویا, California, United States