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1. The Sloan Digital Sky Survey Reverberation Mapping Project : sample characterization

Author

Karen Kinemuchi, Gordon T. Richards, Eric Morganson, Donald P. Schneider, Linhua Jiang, Patrick B. Hall, Guangtun Zhu, D. A. Starkey, Ian D. McGreer, Paul J. Green, Hengxiao Guo, Eugene A. Magnier, Rolf-Peter Kudritzki, Jonathan R. Trump, Christopher Waters, Yue Shen, K. C. Chambers, Luis C. Ho, Nick Kaiser, Jennifer I-Hsiu Li, Catherine J. Grier, T. Simm, Y. Homayouni, Shu Wang, W. N. Brandt, Patrick Petitjean, Keith Horne, University of St Andrews. School of Physics and Astronomy, University of St Andrews. St Andrews Centre for Exoplanet Science, University of Illinois at Urbana-Champaign [Urbana], University of Illinois System, York University [Toronto], SUPA School of Physics and Astronomy [University of St Andrews], University of St Andrews [Scotland]-Scottish Universities Physics Alliance (SUPA), Johns Hopkins University (JHU), Steward Observatory, University of Arizona, Max-Planck-Institut, University of Connecticut (UCONN), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Pennsylvania State University (Penn State), Penn State System, DeKalb Observatory, Laboratoire de Génie Electrique de Grenoble (G2ELab), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), University of Hawai'i [Honolulu] (UH), Astrophysique, Laboratoire de physique de l'ENS - ENS Paris (LPENS (UMR_8023)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Université Paris Diderot - Paris 7 (UPD7)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Université Paris Diderot - Paris 7 (UPD7)

Subjects
[PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], active [Galaxies], Library science, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Surveys, 01 natural sciences, Max planck institute, 0103 physical sciences, QB Astronomy, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, QB, Physics, 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, general [Quasars], DAS, Black hole physics, Astrophysics - Astrophysics of Galaxies, profiles [Line], [PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics - Instrumentation and Methods for Astrophysics, National laboratory
Abstract

We present a detailed characterization of the 849 broad-line quasars from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. Our quasar sample covers a redshift range of 0.1, Comment: Updated to match the accepted version (minor corrections). Catalog data and software tools are available at ftp://quasar.astro.illinois.edu/public/sdssrm/paper_data/Sample_char/

Published
2019
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2. SPIDERS: Selection of spectroscopic targets using AGN candidates detected in all-sky X-ray surveys

Author

Scott F. Anderson, D. Coffey, Chichuan Jin, Johannes Buchner, Tom Dwelly, A. Del Moro, Axel Schwope, M. L. Menzel, Paul J. Green, Nicolas Clerc, Antonis Georgakakis, Th. Boller, Andrea Merloni, Marcella Brusa, W. N. Brandt, J. Ridl, Robert C. Nichol, T. Simm, Kirpal Nandra, Tamás Budavári, Mara Salvato, Adam D. Myers, Institut de recherche en astrophysique et planétologie ( IRAP ), Université Paul Sabatier - Toulouse 3 ( UPS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Dwelly, T., Salvato, M., Merloni, A., Brusa, M., Buchner, J., Anderson, S. F., Boller, T. h., Brandt, W. N., Budavári, T., Clerc, N., Coffey, D., Del Moro, A., Georgakakis, A., Green, P. J., Jin, C., Menzel, M. -. L., Myers, A. D., Nandra, K., Nichol, R. C., Ridl, J., Schwope, A. D., and Simm, T.

Subjects
media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], galaxies: active, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Cosmology, surveys, quasars: general, 0103 physical sciences, ROSAT, Cluster analysis, 010303 astronomy & astrophysics, Galaxy cluster, Selection (genetic algorithm), Astrophysics::Galaxy Astrophysics, media_common, surveys, galaxies: active, quasars: general, galaxies: Seyfert, cosmology: observations, X-rays: galaxies, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Redshift, galaxies: Seyfert, X-rays: galaxies, Space and Planetary Science, Sky, Astrophysics of Galaxies (astro-ph.GA), cosmology: observations, Magnitude (astronomy), Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

SPIDERS (SPectroscopic IDentification of eROSITA Sources) is an SDSS-IV survey running in parallel to the eBOSS cosmology project. SPIDERS will obtain optical spectroscopy for large numbers of X-ray-selected AGN and galaxy cluster members detected in wide area eROSITA, XMM-Newton and ROSAT surveys. We describe the methods used to choose spectroscopic targets for two sub-programmes of SPIDERS: X-ray selected AGN candidates detected in the ROSAT All Sky and the XMM-Newton Slew surveys. We have exploited a Bayesian cross-matching algorithm, guided by priors based on mid-IR colour-magnitude information from the WISE survey, to select the most probable optical counterpart to each X-ray detection. We empirically demonstrate the high fidelity of our counterpart selection method using a reference sample of bright well-localised X-ray sources collated from XMM-Newton, Chandra and Swift-XRT serendipitous catalogues, and also by examining blank-sky locations. We describe the down-selection steps which resulted in the final set of SPIDERS-AGN targets put forward for spectroscopy within the eBOSS/TDSS/SPIDERS survey, and present catalogues of these targets. We also present catalogues of ~12000 ROSAT and ~1500 XMM-Newton Slew survey sources which have existing optical spectroscopy from SDSS-DR12, including the results of our visual inspections. On completion of the SPIDERS program, we expect to have collected homogeneous spectroscopic redshift information over a footprint of ~7500 deg$^2$ for >85 percent of the ROSAT and XMM-Newton Slew survey sources having optical counterparts in the magnitude range 17, Comment: MNRAS, accepted

Published
2017
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3. Pan-STARRS1 variability of XMM-COSMOS AGN. II. Physical correlations and power spectrum analysis

Author

Roberto P. Saglia, Giorgio Lanzuisi, Kirpal Nandra, Gabriele Ponti, Mara Salvato, Benny Trakhtenbrot, T. Simm, Ralf Bender, Simm, T., Salvato, M., Saglia, R., Ponti, G., Lanzuisi, G., Trakhtenbrot, B., Nandra, K., and Bender, R.

Subjects
Active galactic nucleus, Hubble Deep Field, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Luminosity, Black hole physic, Accretion, accretion disk, 0103 physical sciences, 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, Astronomy and Astrophysics, Quasar, Galaxies: active, Astronomy and Astrophysic, Light curve, Astrophysics - Astrophysics of Galaxies, Redshift, Black hole, Quasars: general, Amplitude, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics - High Energy Astrophysical Phenomena, X-rays: galaxie, Methods: data analysi
Abstract

[Abbreviated] We search for scaling relations between the fundamental AGN parameters and rest-frame UV/optical variability properties for a sample of $\sim$90 X-ray selected AGNs covering a wide redshift range from the XMM-COSMOS survey, with optical light curves in four bands provided by the Pan-STARRS1 (PS1) Medium Deep Field 04 survey. To estimate the variability amplitude we utilize the normalized excess variance ($\sigma_{\mathrm{rms}}^{2}$) and probe variability on rest-frame timescales of several months and years by calculating $\sigma_{\mathrm{rms}}^{2}$ from different parts of our light curves. In addition, we derive the rest-frame optical PSD for our sources using continuous-time autoregressive moving average (CARMA) models. We observe that the excess variance and the PSD amplitude are strongly anti-correlated with wavelength, bolometric luminosity and Eddington ratio. There is no evidence for a dependency of the variability amplitude on black hole mass and redshift. These results suggest that the accretion rate is the fundamental physical quantity determining the rest-frame UV/optical variability amplitude of quasars on timescales of months and years. The optical PSD of all of our sources is consistent with a broken power law showing a characteristic bend at rest-frame timescales ranging between $\sim$100 and $\sim$300 days. The break timescale exhibits no significant correlation with any of the fundamental AGN parameters. The low frequency slope of the PSD is consistent with a value of $-1$ for most of our objects, whereas the high frequency slope is characterized by a broad distribution of values between $\sim-2$ and $\sim-4$. These findings unveil significant deviations from the simple "damped random walk" model, frequently used in previous optical variability studies. We find a weak tendency for AGNs with higher black hole mass having steeper high frequency PSD slopes., Comment: Accepted by A&A, 23 pages, 19 figures

Published
2015

4. The Influence of Lath, Block and Prior Austenite Grain (PAG) Size on the Tensile, Creep and Fatigue Properties of Novel Maraging Steel.

Author

Simm T, Sun L, McAdam S, Hill P, Rawson M, and Perkins K

Abstract

The influence of martensitic microstructure and prior austenite grain (PAG) size on the mechanical properties of novel maraging steel was studied. This was achieved by looking at two different martensitic structures with PAG sizes of approximately 40 µm and 80 µm, produced by hot rolling to different reductions. Two ageing heat-treatments were considered: both heat-treatments consisted of austenisation at 960 °C, then aging at 560 °C for 5 h, but while one was rapidly cooled the other was slow cooled and then extended aged at 480 °C for 64 h. It is shown that for the shorter ageing treatment the smaller PAG size resulted in significant improvements in strength (increase of more than 150 MPa), ductility (four times increase), creep life (almost four times increase in creep life) and fatigue life (almost doubled). Whereas, the extended aged sample showed similar changes in the fatigue life, elongation and hardness it displayed yet showed no difference in tensile strength and creep. These results display the complexity of microstructural contributions to mechanical properties in maraging steels.

Published
2017
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