DOCSLIB.ORG

XMM-Newton Observations of Seyfert Galaxies from the Palomar Spectroscopic Survey: the X-Ray Absorption Distribution

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

A&A 500, 999–1012 (2009) Astronomy DOI: 10.1051/0004-6361/200811371 & c ESO 2009 Astrophysics XMM-Newton observations of Seyfert galaxies from the Palomar spectroscopic survey: the X-ray absorption distribution A. Akylas and I. Georgantopoulos Institute of Astronomy & Astrophysics, National Observatory of Athens, I. Metaxa & B. Pavlou, Penteli, 15236 Athens, Greece Received 18 November 2008 / Accepted 16 March 2009 ABSTRACT We present XMM-Newton spectral analysis of all 38 Seyfert galaxies from the Palomar spectroscopic sample of galaxies. These are found at distances of up to 67 Mpc and cover the absorbed 2–10 keV luminosity range ∼1038–1043 erg s−1. Our aim is to determine the distribution of the X-ray absorption in the local Universe. Three of these are Compton-thick with column densities just above 24 −2 10 cm and high equivalent width FeKα lines (>700 eV). Five more sources have low values of the X-ray to [OIII] flux ratio suggesting that they could be associated with obscured nuclei. Their individual spectra show neither high absorbing columns nor flat 23 −2 spectral indices. However, their stacked spectrum reveals an absorbing column density of NH ∼ 10 cm . Therefore the fraction of absorbed sources (>1022 cm−2) could be as high as 55 ± 12%. A number of Seyfert-2 appear to host unabsorbed nuclei. These are 41 −1 associated with low-luminosity sources LX < 3 × 10 erg s . Their stacked spectrum again shows no absorption while inspection of the Chandra images, where available, shows that contamination from nearby sources does not affect the XMM-Newton spectra in most cases. Nevertheless, such low luminosity sources are not contributing significantly to the X-ray background flux. When we consider only the brighter, >1041 erg s−1, 21 sources, we find that the fraction of absorbed nuclei rises to 75 ± 19% while that of Compton-thick sources to 15–20%. The fraction of Compton-thick AGN is lower than that predicted by the X-ray background synthesis model in the same luminosity and redshift range. Key words. surveys – X-rays: galaxies – X-rays: general 1. Introduction Compton-thick AGN (see Comastri 2004, for a review) where the Compton scattering on the bound electrons becomes signif- The moderate to high redshift Universe has been probed at un- icant. Despite the fact that Compton-thick AGN are abundant parallelled depth with the most sensitive observations performed in our vicinity (e.g. NGC 1068, Circinus), only a few tens of at X-ray wavelengths in the Chandra Deep fields. The Chandra Compton-thick sources have been identified from X-ray data 2Ms observations (Alexander et al. 2003; Luo et al. 2008)re- (Comastri 2004). Although the population of Compton-thick solved about 80 per cent of the extragalactic X-ray light in the sources remains elusive there is concrete evidence for its pres- hard 2–10 keV band (see Brandt & Hasinger 2005,forare- ence. The X-ray background synthesis models can explain the view). These deep surveys find a sky density of 5000 sources per peak of the X-ray background at 30–40 keV, where most of its square degree, the vast majority of which are found to be AGN energy density lies, (Frontera et al. 2007;Churazovetal.2007) through optical spectroscopy (e.g. Barger et al. 2003). In con- only by invoking a large number of Compton-thick AGN (Gilli trast, the optical surveys for QSOs (e.g. the COMBO-17 survey) et al. 2007). Additional evidence for the presence of a Compton- reach only a surface density about an order of magnitude lower thick population comes from the directly measured space den- (e.g. Wolf et al. 2003). This clearly demonstrates the power of sity of black holes in the local Universe. It is found that this X-ray surveys for detecting AGN. This is because hard X-rays space density is a factor of two higher than that predicted from can penetrate large amounts of gas without suffering from sig- the X-ray luminosity function (Marconi et al. 2004). This imme- nificant absorption. Indeed detailed spectral analysis on X-ray diately suggests that the X-ray luminosity function is missing an selected AGN reveals large amount of obscuration (e.g. Akylas appreciable number of obscured AGN. et al. 2006; Tozzi et al. 2006; Georgantopoulos et al. 2007). In In recent years there have been many efforts to uncover heav- particular, about two thirds of the X-ray sources, over all lumi- 22 −2 ily obscured and in particular Compton-thick AGN in the local nosities, present column densities higher than 10 cm .These Universe by examining IR or optically selected, [OIII], AGN high absorbing columns are believed to originate in a molecular samples. This is because both the IR and the narrow-line re- torus surrounding the nucleus. gion originate beyond the obscuring region and thus represent However, even the efficient 2–10 keV X-ray surveys may be an isotropic property of the AGN. Risaliti et al. (1999)exam- missing a fraction of highly obscured sources. This is because at ine the X-ray properties of a large sample of [OIII] selected very high obscuring column densities (>1024 cm−2, correspond- Seyfert-2 galaxies whose X-ray spectra were available in the ing to an optical reddening of AV > 100), the X-ray photons literature. They find a large fraction of Compton-thick sources with energies between 2 and 10 keV are absorbed. These are the (over half of their sample). Their estimates are complemented by Article published by EDP Sciences 1000 A. Akylas and I. Georgantopoulos: X-ray absorption in the local universe more recent XMM-Newton observations of local AGN samples 3. X-ray observations (Cappi et al. 2006; Panessa et al. 2006; Guainazzi et al. 2005). All these authors also claim a large Compton-thick AGN frac- The X-ray data have been obtained with the EPIC (European tion exceeding 30 per cent of the Seyfert-2 population. The ad- Photon Imaging Cameras, Strüder et al. 2001; Turner et al. 2001) vent of the SWIFT and INTEGRAL missions which carry X-ray on board XMM-Newton. Thirty sources have been recovered from the XMM-Newton archive while the remaining ten objects detectors with imaging capabilities (e.g. Barthelmy et al. 2005; Ubertini et al. 2003) in ultra-hard X-rays (15–200 keV) try to (marked with a “ ”inTable2) have been observed by us during shed new light on the absorption properties of AGN in the lo- the Guest Observer program. cal Universe. In principle, at these ultra-hard X-rays obscura- The log of all the XMM-Newton observations is shown tion should play a negligible role, at least up to column densities in Table 2. The data have been analysed using the Scientific as high as 1025 cm−2. However, because of the limited effec- Analysis Software (SAS v.7.1). We produce event files for tive area the above surveys can provide X-ray samples, down to both the PN and the MOS observations using the EPCHAIN very bright fluxes 10−11 erg cm−2 s−1, with limited quality spec- and EMCHAIN tasks of SAS respectively. The event files are tra. Again XMM-Newton observations are often required to de- screened for high particle background periods. In our analysis termine the column density in each source. Interestingly, these we deal only with events corresponding to patterns 0–4 for the surveys find only a limited number of Compton-thick sources PN and 0–12 for the MOS instruments. (Markwardt et al. 2005; Bassani et al. 2006; Malizia et al. 2007; The source spectra are extracted from circular regions with radius of 20 arcsec. This area encircles at least the 70 per cent of Ajello 2008; Winter et al. 2008; Tueller et al. 2008; Sazonov ff et al. 2008). the all the X-ray photons at o -axis angles less than 10 arcmin. Here, we present XMM-Newton observations of all 38 A ten times larger source-free area is used for the background Seyfert galaxies in the Palomar spectroscopic sample of nearby estimation. The response and ancillary files are also produced galaxies (Ho et al. 1997). This is the largest complete optically using SAS tasks RMFGEN and ARFGEN respectively. selected AGN sample in the local Universe analyzed so far. 23 of We note that 18 of the XMM-Newton observations pre- the Seyfert galaxies presented here have already been discussed sented here, coincide with these presented in Cappi et al. (2006). in previous works (e.g. Cappi et al. 2006). For 5 of them newer However we choose to re-analyze these common data-sets in or- XMM-Newton observations are available and are presented here. der to present a uniform treatment of the sample. The current work should provide the most unbiased census of the AGN column density distribution at low redshifts and lumi- nosities. 4. X-ray spectral analysis We investigate the X-ray properties of the sources in our sam- 2. The sample ple by performing spectral fittings with XSPEC v.12.4 software package. 2 sources are excluded from the X-ray spectral anal- The Seyfert sample used in this study is derived from the ysis: the Seyfert-2 galaxy NGC185 for being undetected in the Palomar optical spectroscopic survey of nearby galaxies (Ho X-rays (see also Sect. 2), and the Seyfert-1.5 galaxy NGC 1275 et al. 1995). This survey has taken high quality spectra of 486 which belongs to the Perseus cluster and whose X-ray image ◦ bright (BT < 12.5 mag), northern (δ>0 ) galaxies selected shows that its flux is heavily contaminated by diffuse emission.
Recommended publications
  • John J. Cowan Date of Birth: April 3, 1948 Place of Birth: Washington, D.C

    John J. Cowan Date of Birth: April 3, 1948 Place of Birth: Washington, D.C

    VITA NAME: John J. Cowan Date of Birth: April 3, 1948 Place of Birth: Washington, D.C. EDUCATION: 1970 B.A. George Washington University, Washington, D.C. 1972 M.S. Case Institute of Technology, Cleveland, OH 1976 Ph.D. University of Maryland, College Park, MD PROFESSIONAL EXPERIENCE: 2002–present David Ross Boyd Professor, University of Oklahoma, 2002–2002 Research Fellow, University of Texas, Austin, TX 1998–2002 Samuel Roberts Noble Foundation Presidential Professor, University of Oklahoma, Norman, OK 1997–1998 Big XIIFaculty Fellow,University ofOklahoma 1991–1992 Visiting Professor, Department of Astronomy, Columbia University, New York, NY 1989–present Professor, Department of Physics and Astronomy, University of Oklahoma, Norman, OK 1988–1994 Consultant and Participating Guest, Lawrence Livermore National Laboratory, Livermore, CA 1987–1988 Visiting Research Associate, Harvard-Smithsonian Center for Astrophysics, Harvard University, Cambridge, MA 1984–1989 Associate Professor, University of Oklahoma 1979–1984 Assistant Professor, University of Oklahoma 1976–1979 Postdoctoral Research Fellow, Harvard-Smithsonian Center for Astrophysics, Harvard University PROFESSIONAL AND HONORARY SOCIETIES: American Astronomical Society International Astronomical Union Phi Beta Kappa RESEARCH INTERESTS: Stellar evolution, supernovae, nucleosynthesis and abundances Radio observations of supernovae and galaxies JOHN J. COWAN Page 2 PUBLICATIONS J. J. Cowan and W. K. Rose, “Production of 17O and 18O by Means of the Hot CNO Tri-Cycle,” Astrophys. J. (Letters) 201, L45 (1975) J. J. Cowan, M. Kafatos, and W. K. Rose, “Sources of Excitation of the Interstellar Gas and Galactic Structure,” Astrophys. J. 195, 47 (1975) M. F. A’Hearn and J. J. Cowan, “Molecular Production Rates in Comet Kohoutek,” As- tron.
  • CO Multi-Line Imaging of Nearby Galaxies (COMING) IV. Overview Of

    CO Multi-Line Imaging of Nearby Galaxies (COMING) IV. Overview Of

    Publ. Astron. Soc. Japan (2018) 00(0), 1–33 1 doi: 10.1093/pasj/xxx000 CO Multi-line Imaging of Nearby Galaxies (COMING) IV. Overview of the Project Kazuo SORAI1, 2, 3, 4, 5, Nario KUNO4, 5, Kazuyuki MURAOKA6, Yusuke MIYAMOTO7, 8, Hiroyuki KANEKO7, Hiroyuki NAKANISHI9 , Naomasa NAKAI4, 5, 10, Kazuki YANAGITANI6 , Takahiro TANAKA4, Yuya SATO4, Dragan SALAK10, Michiko UMEI2 , Kana MOROKUMA-MATSUI7, 8, 11, 12, Naoko MATSUMOTO13, 14, Saeko UENO9, Hsi-An PAN15, Yuto NOMA10, Tsutomu, T. TAKEUCHI16 , Moe YODA16, Mayu KURODA6, Atsushi YASUDA4 , Yoshiyuki YAJIMA2 , Nagisa OI17, Shugo SHIBATA2, Masumichi SETA10, Yoshimasa WATANABE4, 5, 18, Shoichiro KITA4, Ryusei KOMATSUZAKI4 , Ayumi KAJIKAWA2, 3, Yu YASHIMA2, 3, Suchetha COORAY16 , Hiroyuki BAJI6 , Yoko SEGAWA2 , Takami TASHIRO2 , Miho TAKEDA6, Nozomi KISHIDA2 , Takuya HATAKEYAMA4 , Yuto TOMIYASU4 and Chey SAITA9 1Department of Physics, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan 2Department of Cosmosciences, Graduate School of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan 3Department of Physics, School of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan 4Division of Physics, Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan 5Tomonaga Center for the History of the Universe (TCHoU), University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan 6Department of Physical Science, Osaka Prefecture University, Gakuen 1-1,
  • Radio Sources in Low-Luminosity Active Galactic Nuclei

    Radio Sources in Low-Luminosity Active Galactic Nuclei

    A&A 392, 53–82 (2002) Astronomy DOI: 10.1051/0004-6361:20020874 & c ESO 2002 Astrophysics Radio sources in low-luminosity active galactic nuclei III. “AGNs” in a distance-limited sample of “LLAGNs” N. M. Nagar1, H. Falcke2,A.S.Wilson3, and J. S. Ulvestad4 1 Arcetri Observatory, Largo E. Fermi 5, Florence 50125, Italy 2 Max-Planck-Institut f¨ur Radioastronomie, Auf dem H¨ugel 69, 53121 Bonn, Germany e-mail: [email protected] 3 Department of Astronomy, University of Maryland, College Park, MD 20742, USA Adjunct Astronomer, Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA e-mail: [email protected] 4 National Radio Astronomy Observatory, PO Box 0, Socorro, NM 87801, USA e-mail: [email protected] Received 23 January 2002 / Accepted 6 June 2002 Abstract. This paper presents the results of a high resolution radio imaging survey of all known (96) low-luminosity active galactic nuclei (LLAGNs) at D ≤ 19 Mpc. We first report new 2 cm (150 mas resolution using the VLA) and 6 cm (2 mas resolution using the VLBA) radio observations of the previously unobserved nuclei in our samples and then present results on the complete survey. We find that almost half of all LINERs and low-luminosity Seyferts have flat-spectrum radio cores when observed at 150 mas resolution. Higher (2 mas) resolution observations of a flux-limited subsample have provided a 100% (16 of 16) detection rate of pc-scale radio cores, with implied brightness temperatures ∼>108 K. The five LLAGNs with the highest core radio fluxes also have pc-scale “jets”.
  • SUPERMASSIVE BLACK HOLES and THEIR HOST SPHEROIDS III. the MBH − Nsph CORRELATION

    SUPERMASSIVE BLACK HOLES and THEIR HOST SPHEROIDS III. the MBH − Nsph CORRELATION

    The Astrophysical Journal, 821:88 (8pp), 2016 April 20 doi:10.3847/0004-637X/821/2/88 © 2016. The American Astronomical Society. All rights reserved. SUPERMASSIVE BLACK HOLES AND THEIR HOST SPHEROIDS. III. THE MBH–nsph CORRELATION Giulia A. D. Savorgnan Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia; [email protected] Received 2015 December 6; accepted 2016 March 6; published 2016 April 13 ABSTRACT The Sérsic R1 n model is the best approximation known to date for describing the light distribution of stellar spheroidal and disk components, with the Sérsic index n providing a direct measure of the central radial concentration of stars. The Sérsic index of a galaxy’s spheroidal component, nsph, has been shown to tightly correlate with the mass of the central supermassive black hole, MBH.TheMnBH– sph correlation is also expected from other two well known scaling relations involving the spheroid luminosity, Lsph:theLsph–n sph and the MLBH– sph. Obtaining an accurate estimate of the spheroid Sérsic index requires a careful modeling of a galaxy’s light distribution and some studies have failed to recover a statistically significant MnBH– sph correlation. With the aim of re-investigating the MnBH– sph and other black hole mass scaling relations, we performed a detailed (i.e., bulge, disks, bars, spiral arms, rings, halo, nucleus, etc.) decomposition of 66 galaxies, with directly measured black hole masses, that had been imaged at 3.6 μm with Spitzer.Inthispaper,the third of this series, we present an analysis of the Lsph–n sph and MnBH– sph diagrams.
  • A Nuclear Molecular Outflow in the Seyfert Galaxy NGC 3227

    A Nuclear Molecular Outflow in the Seyfert Galaxy NGC 3227

    Astronomy & Astrophysics manuscript no. ALMANGC3227_final c ESO 2019 June 18, 2019 A nuclear molecular outflow in the Seyfert galaxy NGC 3227 A. Alonso-Herrero1, S. García-Burillo2, M. Pereira-Santaella3, R. I. Davies4, F. Combes5, M. Vestergaard6; 7, S. I. Raimundo6, A. Bunker3, T. Díaz-Santos8, P. Gandhi9, I. García-Bernete10, E. K. S. Hicks11, S. F. Hönig8, L. K. Hunt12, M. Imanishi13; 14, T. Izumi13, N. A. Levenson15, W. Maciejewski16, C. Packham17; 13, C. Ramos Almeida18; 19, C. Ricci8; 20, D. Rigopoulou3, P. F. Roche3, D. Rosario21, M. Schartmann22; 4, A. Usero2, and M. J. Ward21 1 Centro de Astrobiología (CAB, CSIC-INTA), ESAC Campus, E-28692 Villanueva de la Cañada, Madrid, Spain e-mail: [email protected] 2 Observatorio de Madrid, OAN-IGN, Alfonso XII, 3, E-28014 Madrid, Spain 3 Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH, UK 4 Max Planck Institut für extraterrestrische Physik Postfach 1312, D-85741 Garching bei München, Germany 5 LERMA, Obs. de Paris, PSL Research Univ., Collége de France, CNRS, Sorbonne Univ., UPMC, Paris, France 6 DARK, The Niels Bohr Institute, University of Copenhagen, Vibenshuset, Lyngbyvej 2, DK-2100 Copenhagen O., Denmark 7 Steward Observatory, University of Arizona, 933 N. Cherry Avenue, Tucson, Arizona, USA 8 Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago, Chile 9 Department of Physics & Astronomy, University of Southampton, Hampshire SO17 1BJ, Southampton, UK 10 Instituto de Física de Cantabria, CSIC-Universidad de Cantabria, E-39005 Santander, Spain 11 Department of Physics & Astronomy, University of Alaska Anchorage, AK 99508-4664, USA 12 INAF-Osservatorio Astrofisico di Arcetri, Largo E.
  • Astronomy Magazine Special Issue

    Astronomy Magazine Special Issue

    γ ι ζ γ δ α κ β κ ε γ β ρ ε ζ υ α φ ψ ω χ α π χ φ γ ω ο ι δ κ α ξ υ λ τ μ β α σ θ ε β σ δ γ ψ λ ω σ η ν θ Aι must-have for all stargazers η δ μ NEW EDITION! ζ λ β ε η κ NGC 6664 NGC 6539 ε τ μ NGC 6712 α υ δ ζ M26 ν NGC 6649 ψ Struve 2325 ζ ξ ATLAS χ α NGC 6604 ξ ο ν ν SCUTUM M16 of the γ SERP β NGC 6605 γ V450 ξ η υ η NGC 6645 M17 φ θ M18 ζ ρ ρ1 π Barnard 92 ο χ σ M25 M24 STARS M23 ν β κ All-in-one introduction ALL NEW MAPS WITH: to the night sky 42,000 more stars (87,000 plotted down to magnitude 8.5) AND 150+ more deep-sky objects (more than 1,200 total) The Eagle Nebula (M16) combines a dark nebula and a star cluster. In 100+ this intense region of star formation, “pillars” form at the boundaries spectacular between hot and cold gas. You’ll find this object on Map 14, a celestial portion of which lies above. photos PLUS: How to observe star clusters, nebulae, and galaxies AS2-CV0610.indd 1 6/10/10 4:17 PM NEW EDITION! AtlAs Tour the night sky of the The staff of Astronomy magazine decided to This atlas presents produce its first star atlas in 2006.
  • EMISSION-LINE NUCLEI at HUBBLE SPACE TELESCOPE RESOLUTION1 Joseph C

    EMISSION-LINE NUCLEI at HUBBLE SPACE TELESCOPE RESOLUTION1 Joseph C

    The Astrophysical Journal, 654:125Y137, 2007 January 1 # 2007. The American Astronomical Society. All rights reserved. Printed in U.S.A. THE SURVEY OF NEARBY NUCLEI WITH THE SPACE TELESCOPE IMAGING SPECTROGRAPH: EMISSION-LINE NUCLEI AT HUBBLE SPACE TELESCOPE RESOLUTION1 Joseph C. Shields,2 Hans-Walter Rix,3 Marc Sarzi,4 Aaron J. Barth,5 Alexei V. Filippenko,6 Luis C. Ho,7 Daniel H. McIntosh,8 Gregory Rudnick,9,10 and Wallace L. W. Sargent11 Received 2004 August 14; accepted 2006 September 8 ABSTRACT We present results from a program of optical spectroscopy for 23 nearby galaxies with emission-line nuclei. This investigation takes advantage of the spatial resolution of the Hubble Space Telescope to study the structure and energetics of the central 10Y20 pc, and the resulting data have value for quantifying central black hole masses, star formation histories, and nebular properties. This paper provides a description of the experimental design, and new findings from the study of emission lines. The sample targets span a range of nebular spectroscopic class, from H ii to Seyfert nuclei. This data set and the resulting measurements are unique in terms of the sample size, the range of nebular class, and the investigation of physical scales extending down to parsecs. The line ratios indicative of nebular ionization show only modest variations over order-of-magnitude differences in radius, and demonstrate in a sys- tematic way that geometrical dilution of the radiation field from a central source cannot be assumed as a primary driver of ionization structure. Comparisons between large- and small-aperture measurements for the H ii/LINER tran- sition objects provide a new test that challenges conventional wisdom concerning the composite nature of these systems.
  • Classification of Galaxies Using Fractal Dimensions

    Classification of Galaxies Using Fractal Dimensions

    UNLV Retrospective Theses & Dissertations 1-1-1999 Classification of galaxies using fractal dimensions Sandip G Thanki University of Nevada, Las Vegas Follow this and additional works at: https://digitalscholarship.unlv.edu/rtds Repository Citation Thanki, Sandip G, "Classification of galaxies using fractal dimensions" (1999). UNLV Retrospective Theses & Dissertations. 1050. http://dx.doi.org/10.25669/8msa-x9b8 This Thesis is protected by copyright and/or related rights. It has been brought to you by Digital Scholarship@UNLV with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in UNLV Retrospective Theses & Dissertations by an authorized administrator of Digital Scholarship@UNLV. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted.
  • Black Hole Mass Scaling Relations for Spiral Galaxies. I. MBH–M*,Sph Benjamin L

    Black Hole Mass Scaling Relations for Spiral Galaxies. I. MBH–M*,Sph Benjamin L

    The Astrophysical Journal, 873:85 (26pp), 2019 March 1 https://doi.org/10.3847/1538-4357/aaf3b8 © 2019. The American Astronomical Society. All rights reserved. Black Hole Mass Scaling Relations for Spiral Galaxies. I. MBH–M*,sph Benjamin L. Davis1 , Alister W. Graham1 , and Ewan Cameron2 1 Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122, Australia; [email protected] 2 Oxford Big Data Institute, University of Oxford, Oxford OX3 7LF, UK Received 2018 May 18; revised 2018 October 19; accepted 2018 November 13; published 2019 March 6 Abstract ( )–( ) The supermassive black hole mass, MBH bulge stellar mass, M*,sph relation is, obviously, derived using two quantities. We endeavor to provide accurate values for the latter via detailed multicomponent galaxy decompositions for the current full sample of 43 spiral galaxies having directly measured MBH values; 35 of these galaxies have been alleged to contain pseudobulges, 21 have water maser measurements, and three appear bulgeless. This more than doubles the previous sample size of spiral galaxies with a finessed image analysis. We have analyzed near-infrared images, accounting for not only the bulge, disk (exponential, truncated, or inclined), and bar but also spiral arms and rings and additional central components (active galactic nuclei (AGNs),etc.). A symmetric Bayesian analysis finds = +0.35 / 10 +( ± ) υ log (MMBH ☉) (2.44-0.31) log{M*,sph [u(1.15´ 10 M☉ )]} 7.24 0.12 ,with a stellar mass-to-light ratio term. The level of scatter equals that about the MBH–σ* relation. The nonlinear slope rules out the idea that many mergers, coupled with the central limit theorem, produced this scaling relation, and it corroborates previous observational studies and simulations, which have reported a near-quadratic slope at the low-mass end of the MBH– M ,sph diagram.
  • The Herschel Sprint PHOTO ILLUSTRATION: PATRICIA GILLIS-COPPOLA, HERSCHEL IMAGE: WIKIMEDIA S&T

    The Herschel Sprint PHOTO ILLUSTRATION: PATRICIA GILLIS-COPPOLA, HERSCHEL IMAGE: WIKIMEDIA S&T

    The Herschel Sprint PHOTO ILLUSTRATION: PATRICIA GILLIS-COPPOLA, HERSCHEL IMAGE: WIKIMEDIA S&T 34 April 2015 sky & telescope William Herschel’s Extraordinary Night of DiscoveryMark Bratton Recreating the legendary sweep of April 11, 1785 There’s little doubt that William Herschel was the most clearly with his instruments. As we will see, he did make signifi cant astronomer of the 18th century. His accom- occasional errors in interpretation, despite the superior plishments included the discovery of Uranus, infrared optics; for instance, he thought that the planetary nebula radiation, and four planetary satellites, as well as the M57 was a ring of stars. compilation of two extensive catalogues of double and The other factor contributing to Herschel’s interest multiple stars. His most lasting achievement, however, was the success of his sister, Caroline, in her study of the was his exhaustive search for undiscovered star clusters sky. He had built her a small telescope, encouraging her and nebulae, a key component in his quest to understand to search for double stars and comets. She located Messier what he called “the construction of the heavens.” In Her- objects and more, occasionally fi nding star clusters and schel’s time, astronomers were concerned principally with nebulae that had escaped the French astronomer’s eye. the study of solar system objects. The search for clusters Over the course of a year of observing, she discovered and nebulae was, up to that point, a haphazard aff air, with about a dozen star clusters and galaxies, occasionally not- a total of only 138 recorded by all the observers in history.
  • A Search For" Dwarf" Seyfert Nuclei. VII. a Catalog of Central Stellar

    A Search For" Dwarf" Seyfert Nuclei. VII. a Catalog of Central Stellar

    TO APPEAR IN The Astrophysical Journal Supplement Series. Preprint typeset using LATEX style emulateapj v. 26/01/00 A SEARCH FOR “DWARF” SEYFERT NUCLEI. VII. A CATALOG OF CENTRAL STELLAR VELOCITY DISPERSIONS OF NEARBY GALAXIES LUIS C. HO The Observatories of the Carnegie Institution of Washington, 813 Santa Barbara St., Pasadena, CA 91101 JENNY E. GREENE1 Department of Astrophysical Sciences, Princeton University, Princeton, NJ ALEXEI V. FILIPPENKO Department of Astronomy, University of California, Berkeley, CA 94720-3411 AND WALLACE L. W. SARGENT Palomar Observatory, California Institute of Technology, MS 105-24, Pasadena, CA 91125 To appear in The Astrophysical Journal Supplement Series. ABSTRACT We present new central stellar velocity dispersion measurements for 428 galaxies in the Palomar spectroscopic survey of bright, northern galaxies. Of these, 142 have no previously published measurements, most being rela- −1 tively late-type systems with low velocity dispersions (∼<100kms ). We provide updates to a number of literature dispersions with large uncertainties. Our measurements are based on a direct pixel-fitting technique that can ac- commodate composite stellar populations by calculating an optimal linear combination of input stellar templates. The original Palomar survey data were taken under conditions that are not ideally suited for deriving stellar veloc- ity dispersions for galaxies with a wide range of Hubble types. We describe an effective strategy to circumvent this complication and demonstrate that we can still obtain reliable velocity dispersions for this sample of well-studied nearby galaxies. Subject headings: galaxies: active — galaxies: kinematics and dynamics — galaxies: nuclei — galaxies: Seyfert — galaxies: starburst — surveys 1. INTRODUCTION tors, apertures, observing strategies, and analysis techniques.
  • Accretion Disk Versus Jet Orientation in H2O Megamaser Galaxies F

    Accretion Disk Versus Jet Orientation in H2O Megamaser Galaxies F

    A&A 624, A42 (2019) Astronomy https://doi.org/10.1051/0004-6361/201834600 & c F. Kamali et al. 2019 Astrophysics Accretion disk versus jet orientation in H2O megamaser galaxies F. Kamali1;?, C. Henkel1,2, S. Koyama3,1, C. Y. Kuo4, J. J. Condon5, A. Brunthaler1, M. J. Reid6, J. E. Greene7, K. M. Menten1, C. M. V. Impellizzeri5,8, J. A. Braatz5, E. Litzinger9,10, and M. Kadler9 1 Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany e-mail: [email protected], [email protected] 2 Astron. Dept., King Abdulaziz University, PO Box 80203, Jeddah 21589, Saudi Arabia 3 Academia Sinica Institute of Astronomy and Astrophysics, PO Box 23-141, Taipei 10617, Taiwan 4 Physics Department, National Sun Yat-Sen University, No. 70, Lien-Hai Rd, Kaosiung City 80424, Taiwan 5 National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903, USA 6 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 7 Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA 8 Joint ALMA Office, Alonso de Córdova 3107, Vitacura, Santiago, Chile 9 Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Campus Hubland Nord, Emil-Fischer-Str. 31, 97074 Würzburg, Germany 10 Dr. Remeis-Observatory, Erlangen Centre for Astroparticle, Physics, University of Erlangen-Nuremberg, Sternwartstr. 7, 96049 Bamberg, Germany Received 7 November 2018 / Accepted 11 February 2019 ABSTRACT Context. An essential part of the paradigm describing active galactic nuclei is the alignment between the radio jet and the associated rotation axis of the sub-pc accretion disks.