DOCSLIB.ORG

APJL20101.Pdf (1.903Mb)

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
APJL20101.Pdf (1.903Mb) The Astrophysical Journal, 708:171–187, 2010 January 1 doi:10.1088/0004-637X/708/1/171 C 2010. The American Astronomical Society. All rights reserved. Printed in the U.S.A. A MULTI-WAVELENGTH SPECTRAL AND POLARIMETRIC STUDY OF THE JET OF 3C 264 E. S. Perlman1,2, C. A. Padgett2,3, M. Georganopoulos2,3, D. M. Worrall4, J. H. Kastner5, G. Franz5,M.Birkinshaw4, F. Dulwich4,C.P.O’Dea5,S.A.Baum6, W. B. Sparks7, J. A. Biretta7,L.Lara8,10, S. Jester9, and A. Martel7 1 Physics and Space Sciences Department, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901, USA; eperlman@fit.edu 2 Department of Physics, University of Maryland-Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA 3 NASA’s Goddard Space Flight Center, Mail Code 660, Greenbelt, MD 20771, USA 4 Department of Physics, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK 5 Physics Department, Rochester Institute of Technology, 84 Lomb Memorial Drive, Rochester, NY 14623-5603, USA 6 Center for Imaging Science, Rochester Institute of Technology, 54 Lomb Memorial Drive, Rochester, NY 14623-5603, USA 7 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA 8 Dpto. Fis´ıca Teorica´ y del Cosmos, Universidad de Granada, Avenida Fuentenueva s/n, 18071 Granada, Spain 9 Max Planck Institut fur Astronomie, Konigstuhl¨ 17, D-69117 Heidelberg, Germany Received 2009 August 14; accepted 2009 November 5; published 2009 December 9 ABSTRACT We present a comprehensive multi-band spectral and polarimetric study of the jet of 3C 264 (NGC 3862). Included in this study are three Hubble Space Telescope (HST) optical and ultraviolet polarimetry data sets, along with new and archival Very Large Array radio imaging and polarimetry, a re-analysis of numerous HST broadband data sets from the near infrared to the far ultraviolet, and a Chandra ACIS-S observation. We investigate similarities and differences between optical and radio polarimetry, in both degree of polarization and projected magnetic field direction. We also examine the broadband spectral energy distribution of both the nucleus and jet of 3C 264, from the radio through the X-rays. From this, we place constraints on the physics of the 3C 264 system, the jet and its dynamics. We find significant curvature of the spectrum from the near-IR to ultraviolet, and synchrotron breaks steeper than 0.5, a situation also encountered in the jet of M87. This likely indicates velocity and/or magnetic field gradients and more efficient particle acceleration localized in the faster/higher magnetic field parts of the flow. The magnetic field structure of the 3C 264 jet is remarkably smooth; however, we do find complex magnetic field structure that is correlated with changes in the optical spectrum. We find that the X-ray emission is due to the synchrotron process; we model the jet spectrum and discuss mechanisms for accelerating particles to the needed energies, together with implications for the orientation of the jet under a possible spine-sheath model. Key words: galaxies: active – galaxies: elliptical and lenticular, cD – galaxies: jets – polarization – radiation mechanisms: non-thermal Online-only material: color figures 1. INTRODUCTION PKS 1136–135—M. Cara et al. 2010, in preparation). This is in comparison to the ∼34 detected optical extragalactic The characterization of jet polarization properties provides jets.11 Given this dearth of polarimetry observations, it is not a powerful diagnostic of jet physics, particularly with respect surprising that there are few constraints on the configuration of to magnetic field configuration and particle acceleration. Ex- the magnetic fields in optically emitting regions of extragalactic tragalactic jets generally emit a continuum of radiation from jets. Here, we present a comprehensive study of the jet of 3C radio through optical, and often into the X-ray regime. Through 264 that includes radio and optical polarimetry, as well as X-ray matched resolution comparisons of flux density measurements observations of the jet. at various frequencies, we can glean morphological information At a redshift of 0.0217 (Baum et al. 1990), and hence a about particle acceleration regions and jet energetic structure. distance of 94 Mpc, 3C 264 is among the closest known The closest kiloparsec-scale radio–optical jet is that of M87 at bright radio galaxies with an optical jet. Also detected at a distance of 16 Mpc (Tonry 1991). By using matched resolution X-ray energies, its relative proximity makes the 3C 264 jet a polarimetry at different wavelengths and combining this with prime candidate for deep optical, radio and X-ray studies, as we multi-wavelength imaging and X-ray imaging and spectroscopy, present here. It is hosted by NGC 3862, a large elliptical galaxy much information about jet energetics and magnetic fields, offset to the south–east from the center of the cluster Abell three-dimensional structure and particle acceleration can be 1367, and is classified as a Fanaroff–Riley type I radio source constrained (Perlman & Wilson 2005 and references therein). (Fanaroff & Riley 1974). On large scales, it exhibits a twin- There are relatively few jets for which there exists Hubble Space tail radio structure extending to the north–east (Bridle & Vallee Telescope (HST) optical polarimetry compared to the number 1981). On arcsec scales, it consists of a compact core, with that have been detected. As of this writing, a total of 10 optical a one-sided, nearly knot-free jet extending also to the north– jets have HST polarimetry observations (M87—e.g., Perlman east and a weak counter jet (Lara et al. 1997). The optical jet et al. 1999; 3C 273—Thomson et al. 1993; 3C 293—Floyd counterpart extends for only roughly 2 beyond the galaxy core, et al. 2006; 3C 15—Perlman et al. 2006 and Dulwich et al. the latter arcsecond of which is considerably fainter than the 2007; 3C 346—Perlman et al. 2006 and Dulwich et al. 2009; inner jet (Perlman et al. 2006). This short length combined with 3C 66B, 3C 78, 3C 264, and 3C 371—Perlman et al. 2006; the “smoothness” of the jet makes studying this object difficult. 10 Deceased 11 See http://home.fnal.gov/∼jester/optjets/ maintained by S. Jester. 171 172 PERLMAN ET AL. Vol. 708 Table 1 HST Observations a b c d Instrument Filter/Polarizer λ0 FWHM Num Exp Obs Date Time (s) WFPC2/PC F702W 6919 1382 2 1994 Dec 24 280 WFPC2/PC F606W 5997 1502 1 1995 Apr 16 500 WFPC2/PC F791W 7881 1224 2 1996 May 19 750 WFPC2/PC F547M 5483 484 2 1996 May 19 900 NICMOS/NIC2 F110W 11285 3844 4 1998 May 12 448 NICMOS/NIC2 F160W 16030 2772 4 1998 May 12 448 NICMOS/NIC2 F205W 20714 4314 4 1998 May 12 896 STIS/NUV-MAMA F25QTZ 2354 995 1 2000 Feb 12 1800 STIS/FUV-MAMA 25MAMA 1374 318 1 2000 Feb 12 1705 STIS/FUV-MAMA F25SRF2 1469 281 1 2000 Feb 12 1700 WFPC2/PC F702W 6919 1382 9 2002 Mar 30 1400 ACS/HRC F606W/POL0V 5895 1588 2 2002 Dec 05 300 ACS/HRC F606W/POL60V 5895 1588 2 2002 Dec 05 300 ACS/HRC F606W/POL120V 5895 1588 2 2002 Dec 05 300 ACS/HRC F330W/POL0UV 3372 410 2 2002 Dec 05 300 ACS/HRC F330W/POL60UV 3372 410 2 2002 Dec 05 300 ACS/HRC F330W/POL120UV 3372 410 2 2002 Dec 05 300 WFPC2/PC F555W/POLQe 5439 1232 8 2003 Mar 06 6500 WFPC2/PC F555W/POLQe 5439 1232 8 2003 Apr 25 6500 WFPC2/PC F555W/POLQe 5439 1232 8 2003 Jun 01 6500 Notes. a Pivot wavelength of filter in Å. b Approximate FWHM of filter bandpass in Å. c Number of images in raw data set (including CR-SPLITs). d Total integration time of all images in seconds. e Due to non-rotatability of the WFPC2 polarizer (POLQ), HST was allowed to precess between observations over a ∼2 month time period, simulating the nominal polarizer angles of 0◦,60◦, and 120◦. See the text for details. In particular, in the optical and near-IR useful observations are (corresponding to the latest WMAP cosmology, see Dunkley really only possible with HST, as most adaptive-optics systems et al. 2009), giving a projected linear scale of 0.42 kpc arcsec−1. require a nearby, bright point source. 3C 264 was part of the original Third Cambridge Catalog 2. OBSERVATIONS AND DATA REDUCTION with S159 MHz = 37 Jy (Edge et al. 1959) and the optical jet counterpart was discovered by Crane et al. (1993) with the pre- We obtained polarimetric observations of 3C 264 with the COSTAR Faint Object Camera (FOC) instrument on HST. Since WFPC2 instrument aboard HST as part of the Cycle 10 ob- this initial optical discovery, over 50 ks of HST observing time serving program GO-9142. As part of this same proposal, we has been dedicated to this source alone (e.g., Crane et al. 1993; obtained 38.3 ks of Chandra observations of this source. We Baum et al. 1997, 1998; Hutchings et al. 1998; Martel et al. also observed this object with the VLA in both A and B configu- 1999, 2000; Noel-Storr et al. 2003). More recent observations rations at 8.5 GHz and 22.5 GHz as part of observing program have concentrated on deep optical polarimetry with WFPC2 AP0439. Further observations in many wave bands and instru- (Perlman et al. 2006) and optical and UV polarimetry with the ment configurations with HST have been taken from the online HST Advanced Camera for Surveys (ACS) (Capetti et al. 2007). data archives (Table 1).
Load more

Recommended publications
  • The Title of My
    Research in Astronomy and Astrophysics manuscript no. (LATEX: cgw.tex; printed on January 14, 2020; 2:35) Constraints on individual supermassive binary black holes using observations of PSR J1909 3744 − Yi Feng1,2,3, Di Li1,3, Yan-Rong Li4 and Jian-Min Wang4 1 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China ; [email protected] 2 University of Chinese Academy of Sciences, Beijing 100049, China 3 CAS Key Laboratory of FAST, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 4 Institute of High Energy Physics, Chinese Academy of Sciences,19B Yuquan Road, Beijing 100049, China Abstract We perform a search for gravitational waves (GWs) from several supermassive binary black hole (SMBBH) candidates (NGC 5548, Mrk 231, OJ 287, PG 1302-102, NGC 4151, Ark 120 and 3C 66B) in long-term timing observations of the pulsar PSR J1909 3744 − obtained using the Parkes radio telescope. No statistically significant signals were found. We constrain the chirp masses of those SMBBH candidates and find the chirp mass of NGC 5548 and3C66Btobeless than2.4 109 M and 2.5 109 M (with 95% confidence), respectively. × ⊙ × ⊙ Our upperlimits remaina factor of 3 to 370 abovethe likely chirp masses for these candidates as estimated from other approaches. The observations processed here provide upper limits on the GW strain amplitude that improve upon the results from the first Parkes Pulsar Timing arXiv:1907.03460v2 [astro-ph.IM] 13 Jan 2020 Array data release by a factor of 2 to 7. We investigate how information about the orbital pa- rameters can help improve the search sensitivity for individual SMBBH systems.
    [Show full text]
  • 198 8Apj. . .329. .532K the Astrophysical Journal, 329:532-550
    .532K The Astrophysical Journal, 329:532-550,1988 June 15 © 1988. The American Astronomical Society. All rights reserved. Printed in U.S.A. .329. 8ApJ. 198 THE OPTICAL CONTINUA OF EXTRAGALACTIC RADIO JETS1 William C. Keel Sterrewacht Leiden Received 1987 August 11 ; accepted 1987 December 11 ABSTRACT Multicolor optical images have been used to measure the broad-band spectral shapes of radio jets known to show optical counterparts, and to search for such counterparts in additional objects. One new detection, the brightest knot in the NGC 6251 jet, is reported. In all cases, except part of the 3C 273 jet, the jet continua are well-represented by synchrotron spectra from truncated power-law electron distributions, with emitted-frame critical frequencies between 3 x 1014 and 2 x 1015 Hz. This may be due to fine structure in the jets or to the particle (re)acceleration process. Two hot spots (Pic A and 3C 303) differ from the jets, in showing unbroken power-law spectra from the radio to the B band. Image restoration has been used to examine the sub-arcsecond structure of the M87 jet and derive spectral shapes for various knots free of blending problems. The structure matches that seen in the radio to the Ol'S level, implying that the jet structure prevents particles from streaming freely over this distance (~30pc) Significant changes in turnover frequency occur from knot to knot, with an overall trend of higher frequency closer to the nucleus. Knot A is an exception, with a spectrum like the features near the core. An Appendix gives results of surface photometry for the program galaxies.
    [Show full text]
  • University of Southampton Research Repository Eprints Soton
    University of Southampton Research Repository ePrints Soton Copyright © and Moral Rights for this thesis are retained by the author and/or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder/s. The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders. When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given e.g. AUTHOR (year of submission) "Full thesis title", University of Southampton, name of the University School or Department, PhD Thesis, pagination http://eprints.soton.ac.uk UNIVERSITY OF SOUTHAMPTON The epoch and environmental dependence of radio-loud active galaxy feedback by Judith Ineson Thesis for the degree of Doctor of Philosophy in the FACULTY OF PHYSICAL SCIENCES AND ENGINEERING Department of Physics and Astronomy June 2016 UNIVERSITY OF SOUTHAMPTON ABSTRACT FACULTY OF PHYSICAL SCIENCES AND ENGINEERING Department of Physics and Astronomy Doctor of Philosophy THE EPOCH AND ENVIRONMENTAL DEPENDENCE OF RADIO-LOUD ACTIVE GALAXY FEEDBACK by Judith Ineson This thesis contains the first systematic X-ray investigation of the relationships between the properties of different types of radio-loud AGN and their large-scale environments, using samples at two distinct redshifts to isolate the effects of evolution. I used X-ray ob- servations of the galaxy clusters hosting the radio galaxies to characterise the properties of the environments and compared them with the low-frequency radio properties of the AGN.
    [Show full text]
  • Tev Gamma-Ray Observations of Mrk421 and H1426+428 with TACTIC Imaging Telescope
    TeV Gamma-Ray Observations of Mrk421 and H1426+428 with TACTIC Imaging Telescope A Thesis submitted to the University of Mumbai for the Ph. D. (SCIENCE) Degree in PHYSICS Submitted By Kuldeep Kumar Yadav Under the Guidance of Dr. R. C. Rannot arXiv:1109.1967v1 [astro-ph.CO] 9 Sep 2011 Astrophysical Sciences Division Bhabha Atomic Research Centre Trombay, Mumbai 400 085 October 2010 Dedicated to My Parents ii iii STATEMENT BY THE CANDIDATE As required by the University Ordinance 770, I wish to state that the work embodied in this thesis titled “ TeV Gamma-Ray Observations of Mrk421 and H1426+428 with TACTIC Imaging Telescope” forms my own contri- bution to the research work carried out under the guidance of Dr. R.C. Ran- not at Astrophysical Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai. This work has not been submitted for any other degree of this or any other University. Whenever reference have been made to previ- ous works of others, it has been clearly indicated as such and included in the Bibliography. ———————————– Signature of candidate Name : Kuldeep Kumar Yadav Certified by ———————————– Signature of Guide Name : Dr. R. C. Rannot Abstract We have observed extragalactic sources Mrk421 (z=0:30) and H1426+428 (z=0:129) in very high energy γ-ray region using TACTIC telescope at Mount Abu (24:6◦N, 72:7◦E, 1300 m asl), Rajasthan, India. Both of these sources belong to the blazar sub-class of active galactic nuclei whose jets are closely aligned to our line of sight. Blazars are most extreme and pow- erful variable sources of radiation of energies ranging from the radio to the γ-ray regimes.
    [Show full text]
  • Extragalactic Radio Jets
    Annual Reviews www.annualreviews.org/aronline Ann. Rev. Astron.Astrophys. 1984. 22 : 319-58 Copyright© 1984 by AnnualReviews Inc. All rights reserved EXTRAGALACTIC RADIO JETS Alan H. Bridle National Radio AstronomyObservatory, 1 Charlottesville, Virginia 22901 Richard A. Perley National Radio Astronomy Observatory, Socorro, New Mexico 87801 1. INTRODUCTION Powerful extended extragalactic radio sources pose two vexing astro- physical problems [reviewed in (147) and (157)]. First, from what energy reservoir do they draw their large radio luminosities (as muchas 10a8 W between 10 MHzand 100 GHz)?Second, how does the active center in the parent galaxy or QSOsupply as muchas 10~4 J in relativistic particles and fields to radio "lobes" up to several hundredkiloparsecs outside the optical object? Newaperture synthesis arrays (68, 250) and new image-processing algorithms (66, 101, 202, 231) have recently allowed radio imaging subarcsecond resolution with high sensitivity and high dynamicrange; as a result, the complexityof the brighter sources has been revealed clearly for the first time. Manycontain radio jets, i.e. narrow radio features between compact central "cores" and more extended "lobe" emission. This review examinesthe systematic properties of such jets and the dues they give to the by PURDUE UNIVERSITY LIBRARY on 01/16/07. For personal use only. physics of energy transfer in extragalactic sources. Wedo not directly consider the jet production mechanism,which is intimately related to the Annu. Rev. Astro. Astrophys. 1984.22:319-358. Downloaded from arjournals.annualreviews.org first problemnoted above--for reviews, see (207) and (251). 1. i Why "’Jets"? Baade & Minkowski(3) first used the term jet in an extragalactic context, describing the train of optical knots extending ,-~ 20" from the nucleus of M87; the knots resemble a fluid jet breaking into droplets.
    [Show full text]
  • Structure in Radio Galaxies
    Atxention Microfiche User, The original document from which this microfiche was made was found to contain some imperfection or imperfections that reduce full comprehension of some of the text despite the good technical quality of the microfiche itself. The imperfections may "be: — missing or illegible pages/figures — wrong pagination — poor overall printing quality, etc. We normally refuse to microfiche such a document and request a replacement document (or pages) from the National INIS Centre concerned. However, our experience shows that many months pass before such documents are replaced. Sometimes the Centre is not able to supply a "better copy or, in some cases, the pages that were supposed to be missing correspond to a wrong pagination only. We feel that it is better to proceed with distributing the microfiche made of these documents than to withhold them till the imperfections are removed. If the removals are subsequestly made then replacement microfiche can be issued. In line with this approach then, our specific practice for microfiching documents with imperfections is as follows: i. A microfiche of an imperfect document will be marked with a special symbol (black circle) on the left of the title. This symbol will appear on all masters and copies of the document (1st fiche and trailer fiches) even if the imperfection is on one fiche of the report only. 2» If imperfection is not too general the reason will be specified on a sheet such as this, in the space below. 3» The microfiche will be considered as temporary, but sold at the normal price. Replacements, if they can be issued, will be available for purchase at the regular price.
    [Show full text]
  • Cycle 12 Abstract Catalog
    Cycle 12 Abstract Catalog Generated April 04, 2003 ================================================================================ Proposal Category: GO Scientific Category: ISM AND CIRCUMSTELLAR MATTER ID: 9718 Title: SMC Extinction Curve Towards a Quiescent Molecular Cloud PI: Francois Boulanger PI Institution: Institut d'Astrophysique Spatiale The lack of 2175 A bump in the SMC extinction curve is interpreted as an absence of small carbon grains. ISO Mid-IR observations support this interpretation by showing that PAH features are absent in the spectra of SMC and LMC massive star forming regions. However, the only ISO observation of an SMC quiescent molecular cloud shows all PAH features, indicating a PAH abundance relative to large dust grains similar to that of Milky Way clouds. We identified a reddened B2III star associated with this cloud. We propose to observe it with STIS. This observation will provide the first measure of the extinction properties of SMC dust away from star forming regions. It will allow us to disentangle the effects of metallicity and massive stars on the SMC extinction curve and dust composition and to assess the relevance of the SMC bump-free extinction curve to low metallicity and/or starburst galaxies in general. ================================================================================ Proposal Category: GO Scientific Category: STELLAR POPULATIONS ID: 9719 Title: Search For Metallicity Spreads in M31 Globular Clusters PI: Terry Bridges PI Institution: Anglo-Australian Observatory Our recent deep HST photometry of the M31 halo globular cluster (GC) Mayall~II, also called G1, has revealed a red-giant branch with a clear spread that we attribute to an intrinsic metallicity dispersion of at least 0.4 dex in [Fe/H].
    [Show full text]
  • WISE J233237.05–505643.5: a Double-Peaked, Broad-Lined Active Galactic Nucleus with a Spiral-Shaped Radio Morphology
    WISE J233237.05–505643.5: A Double-peaked, Broad-lined Active Galactic Nucleus with a Spiral-shaped Radio Morphology. The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Tsai, Chao-Wei, T. H. Jarrett, Daniel Stern, Bjorn Emonts, R. Scott Barrows, Roberto J. Assef, Ray P. Norris, et al. 2013. “WISE J233237.05–505643.5: A Double-peaked, Broad-lined Active Galactic Nucleus with a Spiral-shaped Radio Morphology.” The Astrophysical Journal 779 (1) (December 10): 41. doi:10.1088/0004-637x/779/1/41. http://dx.doi.org/10.1088/0004-637X/779/1/41. Published Version 10.1088/0004-637X/779/1/41;doi:10.1088/0004-637x/779/1/41 Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:11829463 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA The Astrophysical Journal, 779:41 (14pp), 2013 December 10 doi:10.1088/0004-637X/779/1/41 C 2013. The American Astronomical Society. All rights reserved. Printed in the U.S.A. WISE J233237.05−505643.5: A DOUBLE-PEAKED, BROAD-LINED ACTIVE GALACTIC NUCLEUS WITH A SPIRAL-SHAPED RADIO MORPHOLOGY Chao-Wei Tsai1,2, T. H. Jarrett3, Daniel Stern2, Bjorn Emonts4,5, R. Scott Barrows6, Roberto J. Assef2,7, Ray P. Norris5, Peter R. M. Eisenhardt2, Carol Lonsdale8, Andrew W.
    [Show full text]
  • I ; the Astrophysical Journal Supplement Series
    \—IU ; The Astrophysical Journal Supplement Series, 72:41-59,1990 January ^ © 1990. The American Astronomical Society. AU rights reserved. Printed in U.S.A. r" C/} ft 1 OPTICAL OBSERVATIONS OF GALAXIES CONTAINING RADIO JETS: A CATALOG OF " SOURCES WITH REDSHIFT SMALLER THAN 0.15 L. Colina1,2 Departmento de Física Teórica, Universidad Autónoma de Madrid, Spain; and Space Telescope Science Institute AND I. Pérez-Fournon1 Instituto de Astrofísica de Canarias, La Laguna, Tenerife, Spain Received 1989 April 3; accepted 1989 July 13 ABSTRACT CCD imaging of 47 radio sources from the Bridle and Perley list of galaxies with radio jets is reported. All the observed galaxies are within the redshift range 0.01 <z <> 0.15 and are constrained in position to Ä > -15°. We describe the observations and the reduction procedure. Contour maps of all the sources are presented. Comments on individual galaxies as well as morphological features are given. Subject headings: galaxies: jets — galaxies: structure — radio sources: galaxies I. INTRODUCTION nearby companions play in triggering the radio activity? (5) Over the past few years many authors have devoted their Which is the optical morphology of these radio jet galaxies? attention to survey radio galaxies with high angular resolution On the other hand, since most of the galaxies with radio using the VLA (Parma et al 1987 and their series of papers; jets are low-luminosity radio galaxies, this study can be also Machalski and Condon 1985; O’Dea and Owen 1985a, b; used as a complement to the optical investigations of high- Ulrich and Meier 1984; Bums and Gregory 1982; Bums, luminosity radio galaxies samples (Heckman et al 1986; Lilly White, and Hough, 1981).
    [Show full text]
  • Chandra Observations of the X-Ray Jet in 3C 66B
    Mon. Not. R. Astron. Soc. 326, 1499–1507 (2001) Chandra observations of the X-ray jet in 3C 66B M. J. Hardcastle,P M. Birkinshaw and D. M. Worrall Department of Physics, University of Bristol, Tyndall Avenue, Bristol BS8 1TL Accepted 2001 May 22. Received 2001 May 15; in original form 2001 March 6 ABSTRACT Our Chandra observation of the FR I radio galaxy 3C 66B has resulted in the first detection of an X-ray counterpart to the previously known radio, infrared and optical jet. The X-ray jet is detected up to 7 arcsec from the core and has a steep X-ray spectrum, a < 1:3 ^ 0:1. The overall X-ray flux density and spectrum of the jet are consistent with a synchrotron origin for the X-ray emission. However, the inner knot in the jet has a higher ratio of X-ray to radio emission than the others. This suggests that either two distinct emission processes are present or differences in the acceleration mechanism are required; there may be a contribution to the emission from the inner knot from an inverse Compton process or it may be the site of an early strong shock in the jet. The peak of the brightest radio and X-ray knot is significantly closer to the nucleus in the X-ray than in the radio, which may suggest that the knots are privileged sites for high-energy particle acceleration. 3C 66B’s jet is similar both in overall spectral shape and in structural detail to those in more nearby sources such as M87 and Centaurus A.
    [Show full text]
  • Massive Black Hole Binary Evolution David Merritt Rochester Institute of Technology
    Rochester Institute of Technology RIT Scholar Works Articles 11-22-2005 Massive Black Hole Binary Evolution David Merritt Rochester Institute of Technology Milos Milosavljevic California Institute of Technology Follow this and additional works at: http://scholarworks.rit.edu/article Recommended Citation Merritt, D., Milosavljevic, M., "Massive Black Whole Binary Evolution", Living Reviews in Relativity, 8, (November, 2005). This Article is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Articles by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. Massive Black Hole Binary Evolution David Merritt Rochester Institute of Technology Rochester, NY USA e-mail:[email protected] http://www.rit.edu/ drmsps/ ∼ MiloˇsMilosavljevi´c Theoretical Astrophysics California Institute of Technology Pasadena, CA USA e-mail:[email protected] http://www.tapir.caltech.edu/ milos/ ∼ Abstract Coalescence of binary supermassive black holes (SBHs) would con- stitute the strongest sources of gravitational waves to be observed by LISA. While the formation of binary SBHs during galaxy mergers is al- most inevitable, coalescence requires that the separation between binary components first drop by a few orders of magnitude, due presumably to interaction of the binary with stars and gas in a galactic nucleus. This article reviews the observational evidence for binary SBHs and discusses how they would evolve. No completely convincing case of a bound, binary SBH has yet been found, although a handful of systems (e.g. interacting galaxies; remnants of galaxy mergers) are now believed to contain two arXiv:astro-ph/0410364 v2 12 Sep 2005 SBHs at projected separations of ∼< 1 kpc.
    [Show full text]
  • The Minimum and Maximum Gravitational-Wave Background from Supermassive Binary Black Holes
    MNRAS 000,1{9 (2018) Preprint 22 October 2018 Compiled using MNRAS LATEX style file v3.0 The minimum and maximum gravitational-wave background from supermassive binary black holes Xing-Jiang Zhu1;2?, Weiguang Cui3 and Eric Thrane1;2 1School of Physics and Astronomy, Monash University, Clayton, Vic 3800, Australia 2OzGrav: The Australian Research Council Centre of Excellence for Gravitational Wave Discovery 3Departamento de F´ısica Te´orica, M´odulo 15, Facultad de Ciencias, Universidad Aut´onoma de Madrid, 28049 Madrid, Spain Accepted XXX. Received YYY; in original form ZZZ ABSTRACT The gravitational-wave background from supermassive binary black holes (SMBBHs) has yet to be detected. This has led to speculations as to whether current pulsar timing array limits are in tension with theoretical predictions. In this paper, we use electromagnetic observations to constrain the SMBBH background from above and below. To derive the maximum amplitude of the background, we suppose that equal- mass SMBBH mergers fully account for the local black hole number density. This yields −15 a maximum characteristic signal amplitude at a period of one year Ayr < 2:4 × 10 , which is comparable to the pulsar timing limits. To derive the minimum amplitude requires an electromagnetic observation of an SMBBH. While a number of candidates have been put forward, there are no universally-accepted electromagnetic detections in the nanohertz band. We show the candidate 3C 66B implies a lower limit, which is inconsistent with limits from pulsar timing, casting doubt on its binary nature. −17 Alternatively, if the parameters of OJ 287 are known accurately, then Ayr > 6:1×10 at 95% confidence level.
    [Show full text]