Active Galaxies NewsletterAn electronic publication dedicated to the observations and theory of active galaxies
Edited by Megan Argo
The Active Galaxies Newsletter is an electronic publication dedicated to the observation and theory of active galaxies. It is intended to be used to notify others in the field of recently accepted papers, conference proceedings and dissertations, and also contains announcements of jobs and conferences. It is produced monthly and sent to over 600 subscribers.
The Latex macros for submitting contributions of all sorts is available here and are also appended to each issue of the newsletter. The editor may reject submissions which do not use the template.
Information and web-links for upcoming meetings, conferences, jobs and special announcements, as well as recent thesis abstracts can now be directly linked to on the left hand side bar. These pages are updated throughout the month as soon as adverts and announcements are received. To advertise forthcoming job opportunities and meetings please email the editor with the relevant information. These adverts are also run in newsletter itself.
If you wish to be sent the newsletter, please send an email to email@example.com entitled `subscribe'. Available below are the latest editions and archives of the active galaxies newsletter.
Further information on the Active Galaxies Newsletter and submitting contributions or subscribing is available here.
While astro-ph is a valuable resource, the Active Galaxies Newsletter directly targets researchers in this field and in this sense is a complementary resource.
Previous issues of the AGN Newsletter can be found in the Back Issues link on the left side bar.
|Active||An electronic publication dedicated to|
|Galaxies||the observation and theory of|
|No. 207 -- January 2015||Editor: Megan Argo (firstname.lastname@example.org)|
Jobs Adverts - Meetings Adverts - Special Announcements
Welcome to all the new subscribers, and thanks to everyone who contributed to this issue of the Active Galaxies Newsletter. This newsletter is intended to disseminate paper abstracts, meeting announcements, job adverts and other information which may be of interest to the active galaxies community. It is produced monthly and, whilst the deadline for contributions is the last day of the month, contributions may be submitted at any time.
The Latex macros for submitting abstracts and dissertation abstracts are appended to each issue of the newsletter and are also available on the web page. Please note that the editor may reject submissions which do not use the template. As always, any suggestions or feedback regarding the newsletter are welcome.
Happy new year, and thanks for your continued subscription.
A Minor Merger Caught In The Act Of Fueling The AGN In Mrk 509
T.C. Fischer1, D.M. Crenshaw1, S.B. Kraemer2, H.R. Schmitt3, T. Storchi-Bergmann4, and R.A. Riffel5
1. Department of Physics and Astronomy, Georgia State University, Astronomy Offices, 25 Park Place, Suite 600, Atlanta, GA 30303
2. Institute for Astrophysics and Computational Sciences, Department of Physics, The Catholic University of America, Washington, DC 20064
3. Naval Research Laboratory, Washington, DC 20375
4. Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, IF, CP 15051, 91501-970 Porto Alegre, RS, Brazil
5. Departamento de Fisica, Centro de Ciencias Naturais e Exatas, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil
In recent observations by the Hubble Space Telescope (HST) as part of a campaign to discover locations and kinematics of AGN outflows, we found that Mrk 509 contains a 3" (∼2100 pc) linear filament in its central region. Visible in both optical continuum and [OIII] imaging, this feature resembles a 'check mark' of several knots of emission that travel northwest to southeast before jutting towards the nucleus from the southwest. Space Telescope Imaging Spectrograph (STIS/HST) observations along the inner portion of the filament reveal redshifted velocities, indicating that the filament is inflowing. We present further observations of the nucleus in Mrk 509 using the Gemini Near-Infrared Integral Field Spectrograph (NIFS), from which we conclude that this structure cannot be related to previously studied, typical NLR outflows and instead embodies the remains of an ongoing minor merger with a gas-rich dwarf galaxy, therefore providing a great opportunity to study the fueling of an AGN by a minor merger in progress.
Accepted by The Astrophysical Journal
E-mail contact: email@example.com
Preprint available at http://arxiv.org/abs/1412.1444
Compton Thick AGN in the XMM-COSMOS survey
G. Lanzuisi1,2, P. Ranalli1, I. Georgantopoulos1 et al
1. Institute of Astronomy & Astrophysics, National Observatory of Athens, Palaia Penteli, 15236, Athens, Greece
2. INAF - Osservatorio Astronomico di Bologna, Via Ranzani 1, 40127, Bologna, Italy
Heavily obscured, Compton Thick (CT, NH > 1024 cm-2) Active Galactic Nuclei (AGN) may represent an important phase in AGN/galaxy co-evolution and are expected to provide a significant contribution to the cosmic X-ray background at its peak. However, unambiguously identifying CT AGN beyond the local Universe is a challenging task even in the deepest X-ray surveys, and given the expected low spatial density of these sources in the 2-10 keV band, large area surveys are needed to collect sizable samples. Through direct X-ray spectra analysis, we selected 39 heavily obscured AGN (NH > 3 × 1023 cm-2) at bright xray fluxes (F2-10 ≳ 10-14 erg s-1 cm-2) in the 2 deg2 XMM-COSMOS survey. After selecting CT AGN based on the fit of a simple absorbed two power law model to the shallow XMM data, the presence of bona-fide CT AGN was confirmed in 80% of the sources using deeper Chandra data and more complex models. The final sample comprises 10 CT AGN (6 of them also have a detected Fe Kα line with EW ∼1 keV), spanning a large range of redshift (z ∼ 0.1 - 2.5) and luminosity (L2-10 ∼ 1043.5 − 1045 ergs) and is complemented by 29 heavily obscured AGN spanning the same redshift and luminosity range. We collected the rich multi-wavelength information available for all these sources, in order to study the distribution of SMBH and host properties, such as BH mass (MBH), Eddington ratio (λEdd), stellar mass (M*), specific star formation rate (sSFR) in comparison with a sample of unobscured AGN. We find that highly obscured sources tend to have significantly smaller MBH and higher λEdd with respect to unobscured sources, while a weaker evolution in M* is observed. The sSFR of highly obscured sources is consistent with the one observed in the main sequence of star forming galaxies, at all redshift. We also present and briefly discuss optical spectra, broad band spectral energy distribution (SED) and morphology for the sample of 10 CT AGN. Both the optical spectra and SED agree with the classification as highly obscured sources: all the available optical spectra are dominated by the stellar component of the host galaxy, and to reproduce the broad band SED, an highly obscured torus component is needed for all the CT sources. Exploiting the high resolution Hubble-ACS images available, we are able to show that these highly obscured sources have a significantly larger merger fraction with respect to other xray selected samples of AGN. Finally we discuss the implications of our findings in the context of AGN/galaxy co-evolutionary models, and compare our results with the predictions of xray background synthesis models.
Accepted by A&A on 25 November 2014.
E-mail contact: firstname.lastname@example.org
Preprint available at: http://arxiv.org/pdf/1409.1867v2.pdf
Very Large Baseline Array observations of Mrk6: probing the jet-lobe connection
P. Kharb1, C. P. O'Dea2, S. A. Baum2, M. J. Hardcastle3, D. Dicken4, J. H. Croston5, B. Mingo6, J. Noel-Storr2
1. Indian Institute of Astrophysics, II Block, Koramangala, Bangalore 560034, India
2. Rochester Institute of Technology, Rochester, NY 14623, USA
3. School of Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK
4. CEA-Saclay, F-91191 Gif-sur-Yvette, France
5. School of Physics and Astronomy, University of Southampton, Southampton, Hampshire SO17 1BJ, UK
6. Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH, UK
We present the results of high-resolution VLBI (very long baseline interferometry) observations at 1.6 and 4.9 GHz of the radio-loud Seyfert galaxy, Mrk6. These observations are able to detect a compact radio core in this galaxy for the first time. The core has an inverted spectral index (α1.6
4.9 = +1.0±0.2) and a brightness temperature of 1×108 K. Three distinct radio components, which resemble jet elements and/or hotspots, are also detected. The position angles of these elongated jet elements point not only to a curved jet in Mrk6, but also towards a connection between the AGN and the kpc-scale radio lobes/bubbles in this galaxy. Firmer constraints on the star formation rate provided by new Herschel observations (SFR < 0.8 M⊙ yr-1) make the starburst-wind-powered bubble scenario implausible. From plasma speeds, obtained via prior Chandra X-ray observations, and ram pressure balance arguments for the interstellar medium and radio bubbles, the north-south bubbles are expected to take 7.5 × 106 yr to form, and the east-west bubbles 1.4 × 106 yr. We suggest that the jet axis has changed at least once in Mrk6 within the last ≈107 yr. A comparison of the nuclear radio-loudness of Mrk6 and a small sample of Seyfert galaxies with a subset of low-luminosity FR I radio galaxies reveals a continuum in radio properties.
Accepted by MNRAS
E-mail contact: email@example.com
Preprint available at http://arxiv.org/abs/1402.7174
VLBI Imaging of the Double Peaked Emission Line Seyfert KISSR1494
P. Kharb1, M. Das1, Z. Paragi2, S. Subramanian1, L. P. Chitta1
1. Indian Institute of Astrophysics, II Block, Koramangala, Bangalore 560034, India
2. Joint Institute for VLBI in Europe, Postbus 2, 7990 AA Dwingeloo, the Netherlands
We present here the results from dual-frequency phase-referenced VLBI observations of the Seyfert galaxy KISSR1494, which exhibits double peaked emission lines in its SDSS spectrum. We detect a single radio component at 1.6 GHz, but not at 5 GHz implying a spectral index steeper than −1.5±0.5 (Sν ∝ να). The high brightness temperature of the radio component (∼1.4 × 107 K) and the steep radio spectrum support a non-thermal synchrotron origin. A crude estimate of the black hole mass derived from the MBH − σ☆ relation is ∼1.4±1.0×108 M⊙; it is accreting at an Eddington rate of ∼0.02. The radio data are consistent with either the radio emission coming from the parsec-scale base of a synchrotron wind originating in the magnetised corona above the accretion disk, or from the inner ionised edge of the accretion disk or torus. In the former case, the narrow line region (NLR) clouds may form a part of the broad outflow, while in the latter, the NLR clouds may form a part of an extended disk beyond the torus. The radio and NLR emission may also be decoupled so that the radio emission originates in an outflow while the NLR is in a disk, and vice versa. While with the present data, it is not possible to clearly distinguish between these scenarios, there appears to be greater circumstantial evidence supporting the coronal wind picture in KISSR1494. From the kiloparsec-scale radio emission, the time-averaged kinetic power of this outflow is estimated to be Q ≈ 1.5×1042 erg s-1, which is typical of radio outflows in low-luminosity AGN. This supports the idea that radio "jets" and outflowing coronal winds are indistinguishable in Seyfert galaxies.
Accepted by ApJ
E-mail contact: firstname.lastname@example.org
Preprint available at: http://arxiv.org/abs/1412.0400
Variability-selected active galactic nuclei in the VST-SUDARE/VOICE survey of the COSMOS field
D. De Cicco1, M. Paolillo1,2,3, G. Covone1,2, S. Falocco1,2, G. Longo1,4, A. Grado5, L. Limatola5, M. T. Botticella5, G. Pignata6,7, E. Cappellaro8, M. Vaccari9, D. Trevese10, F. Vagnetti11, M. Salvato12, M. Radovich8, W. N. Brandt13,14, M. Capaccioli1, N. R. Napolitano5, P. Schipani5
1. Department of Physics, University of Napoli ``Federico II'', via Cinthia 9, 80126 Napoli, Italy
2. INFN - Sezione di Napoli, via Cinthia 9, 80126 Napoli, Italy
3. ASI Science Data Center, via del Politecnico snc, 00133 Roma, Italy
4. Visiting associate - Department of Astronomy, California Institute of Technology, CA 90125, USA
5. INAF - Osservatorio Astronomico di Capodimonte, via Moiariello 16, 80131 Napoli, Italy
6. Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago, Chile
7. Millennium Institute of Astrophysics, Santiago, Chile
8. INAF - Osservatorio Astronomico di Padova, vicolo dell'Osservatorio 5, I-35122 Padova, Italy
9. Astrophysics Group, Department of Physics, University of the Western Cape, Private Bag X17, 7535 Bellville, Cape Town, South Africa
10. Department of Physics, University of Roma ``La Sapienza'', Piazzale Aldo Moro 2, 00185 Roma, Italy
11. Department of Physics, University of Roma ``Tor Vergata'', via della Ricerca Scientifica 1, 00133 Roma, Italy
12. Max Planck Institut für Extraterrestrische Physik, Giessenbachstraße 1, D-85748 Garching bei München, Germany
13. Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802, USA
14. Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, PA 16802, USA
Active galaxies are characterized by variability at every wavelength, with timescales from hours to years depending on the observing window. Optical variability has proven to be an effective way of detecting AGNs in imaging surveys, lasting from weeks to years. In the present work we test the use of optical variability as a tool to identify active galactic nuclei in the VST multiepoch survey of the COSMOS field, originally tailored to detect supernova events. We make use of the multiwavelength data provided by other COSMOS surveys to discuss the reliability of the method and the nature of our AGN candidates. The selection on the basis of optical variability returns a sample of 83 AGN candidates; based on a number of diagnostics, we conclude that 67 of them are confirmed AGNs (81% purity), 12 are classified as supernovae, while the nature of the remaining 4 is unknown. For the subsample of AGNs with some spectroscopic classification, we find that Type 1 are prevalent (89%) compared to Type 2 AGNs (11%). Overall, our approach is able to retrieve on average 15% of all AGNs in the field identified by means of spectroscopic or X-ray classification, with a strong dependence on the source apparent magnitude (completeness ranging from 26% to 5%). In particular, the completeness for Type 1 AGNs is 25%, while it drops to 6% for Type 2 AGNs. The rest of the X-ray selected AGN population presents on average a larger r.m.s. variability than the bulk of non-variable sources, indicating that variability detection for at least some of these objects is prevented only by the photometric accuracy of the data. The low completeness is in part due to the short observing span: we show that increasing the temporal baseline results in larger samples as expected for sources with a red-noise power spectrum. Our results allow us to assess the usefulness of this AGN selection technique in view of future wide-field surveys.
Accepted by A&A
E-mail contact: email@example.com
Preprint available at http://arxiv.org/abs/1412.1488
Storm in a "Teacup": a radio-quiet quasar with ≈10kpc radio-emitting bubbles and extreme gas kinematics
C. M. Harrison1, A. P. Thomson1, D. M. Alexander1, F. E. Bauer2,3,4, A. C. Edge1, M. T. Hogan1, J. R. Mullaney5, and A. M. Swinbank1
1. Department of Physics, Durham University, South Road, Durham, DH1 3LE, U.K.
2. Instituto de Astrofísica, Facultad de Física, Pontifica Universidad Católica de Chile, 306, Santiago 22, Chile
3. Millennium Institute of Astrophysics, Vicuña Mackenna 4860, 7820436 Macul, Santiago, Chile
4. Space Science Institute, 4750 Walnut Street, Suite 205, Boulder, CO 80301, USA
5. Department of Physics and Astronomy, University of Sheffield, Sheffield, S7 3RH, U.K.
We present multi-frequency (1-8GHz) VLA data, combined with VIMOS IFU data and HST imaging, of a z=0.085 radio-quiet type 2 quasar (with L1.4GHz ≈ 5×1023 W Hz-1 and LAGN ≈ 2×1045 ergs-1). Due to the morphology of its emission-line region, the target (J1430+1339) has been referred to as the Teacup AGN in the literature. We identify "bubbles" of radio emission that are extended ≈10−12kpc to both the east and west of the nucleus. The edge of the brighter eastern bubble is co-spatial with an arc of luminous ionized gas. We also show that the Teacup AGN hosts a compact radio structure, located ≈ 0.8kpc from the core position, at the base of the eastern bubble. This radio structure is co-spatial with an ionized outflow with an observed velocity of v = −740 km s-1. This is likely to correspond to a jet, or possibly a quasar wind, interacting with the interstellar medium at this position. The large-scale radio bubbles appear to be inflated by the central AGN, which indicates that the AGN can also interact with the gas on ≳10 kpc scales. Our study highlights that even when a quasar is formally "radio-quiet" the radio emission can be extremely effective for observing the effects of AGN feedback.
Accepted by ApJ
E-mail contact: firstname.lastname@example.org
Preprint available at http://adsabs.harvard.edu/abs/2014arXiv1410.4198H
A Symposium to Honor David Hollenbach's Lifetime in Science
Asilomar, California, USA
June 28 to July 3rd, 2015
The goal of this meeting is to overview the state of the art in theoretical PDR studies, to review the processes that control the physical and chemical conditions in PDRs and their emission characteristics, to compare and contrast these models with recent observations of PDRs obtained with the Spitzer Space Telescope, the Herschel Space Observatory, the Stratospheric Observatory For Infrared Astronomy, and the Atacama Large Millimeter Array, to connect studies of dense PDRs in regions of star formation to the studies of the evolution of the interstellar medium of galaxies over the history of the Universe, and to link and compare and contrast studies of PDRs to those of regions dominated by X-rays, by turbulence, by shocks, and by cosmic rays. In addition, we take this occasion to celebrate the contributions to this field of one of the pioneers, David Hollenbach.
The scientific topics of this meeting include:
- The Physics and Chemistry of PDRs,
- Models of PDRs,
- Observations PDRs in the galactic environment,
- PDRs & star and planet formation,
- PDRs & the ISM of galaxies, and
- PDRs in starburst, (U)LIRG, and high-z environments.
The format of the meeting will consist of invited reviews, invited talks, contributed papers, and poster papers. A list of invited speakers is available on the website.
The Asilomar conference center is a California State Park (http://www.visitasilomar.com) beautifully situated on the coast of the Monterey peninsula in a very quiet and serene setting that we hope will be very conducive to a highly interactive meeting.
SOFIA has generously provided support for deserving students to defer their room and board during the meeting. Students who wish to be considered for a SOFIA travel grant have to send a letter of motivation plus a supporting letter from their supervisor. Details can be found on the website.
Registration is now open.
Early registration is encouraged, as the number of participants will be limited to approximately 150.
Registration and Abstract submission deadline: April 2nd, 2015
Student grant requests: February 20th, 2015
See the website for details.
For more information, visit our website:
We are looking forward to an exciting meeting and hope to welcome you in Asilomar,
On behalf of the Scientific Organizing Committee,
Margaret Meixner & Xander Tielens
Dept of Physics & Astronomy, University of Manitoba
Deadline 28th February 2015
Further Information: http://umanitoba.ca/faculties/science/departments/physics/index.html
The Department of Physics and Astronomy at the University of Manitiba invites applications for a postdoctoral fellow working with Profs. Stefi Baum and Chris O'Dea on multi-wavelength observational studies of Active Galactic Nuclei and/or Clusters of Galaxies.
Candidates must hold a Ph.D. degree in astronomy, physics, or a related subject by the appointment start. The initial appointment will be for one year, renewable for a second and third year upon mutual agreement and availability of funding. The starting date is negotiable between the summer and early fall.
Applicants should submit a cover letter, CV, publication list, and a statement of research interests. Three letters of reference should also be submitted. All information should be emailed to email@example.com. Review of materials will begin Feb 1, 2015.
Winnipeg is the largest city in the Province of Manitoba. The city has a rich cultural environment, including symphony, opera, dance, theatre, and ethnic festivals. The region provides ample opportunities for outdoor recreation in all seasons. Learn more about Winnipeg at http://www.city.winnipeg.mb.ca.
The University of Manitoba is strongly committed to diversity within its community and especially welcomes applications from qualified women and men, visible minority group members, Aboriginal peoples, persons with disabilities, persons of all sexual orientations and genders and others who may contribute to the further diversification of ideas. All qualified candidates are encouraged to apply; however, Canadians and permanent residents will be given priority. Application materials, including letters of reference, will be handled in accordance with the protection of privacy provisions of The Freedom of Information and Protection of Privacy (Manitoba). Please note that your curriculum vitae may be provided to participating members of the search process.