Active Galaxies Newsletter

An 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 agnews@manchester.ac.uk 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.

Latest Issue:

*Active*	An electronic publication dedicated to
*Galaxies*	the observation and theory of
*Newsletter*	active galaxies
*No. 219 -- January 2016*	*Editor: Megan Argo (agnews@manchester.ac.uk)*

Accepted Abstracts - Submitted Abstracts - Thesis Abstracts
Jobs Adverts - Meetings Adverts - Special Announcements

From the Editor

Welcome to all the new subscribers, thanks to everyone who contributed to this issue of the Active Galaxies Newsletter, and a Happy New Year.

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.

Thanks for your continued subscription.

Megan Argo

Abstracts of recently accepted papers

A multi-epoch spectroscopic study of the BAL quasar APM 08279+5255 II. Emission- and absorption-line variability time lags

F. G. Saturni^1,2, D. Trevese¹, F. Vagnetti³, M. Perna⁴ and M. Dadina⁵

1. Università degli Studi di Roma "La Sapienza", p.le A. Moro 5, I-00185 Rome (Italy)
2. Università degli Studi "Roma Tre", via della Vasca Navale 84, I-00146 Rome (Italy)
3. Università di Roma "Tor Vergata", via della Ricerca Scientifica 1, I-00133 Rome (Italy)
4. Università di Bologna, via Zamboni 33, I-40126 Bologna (Italy)
5. INAF-IASF Bologna, via Gobetti 101, I-40129 Bologna (Italy)

The study of high-redshift bright quasars is crucial to gather information about the history of galaxy assembly and evolution. Variability analyses can provide useful data on the physics of quasar processes and their relation with the host galaxy.
In this study, we aim to measure the black hole mass of the bright lensed BAL QSO APM 08279+5255 at z = 3.911 through reverberation mapping, and to update and extend the monitoring of its C IV absorption line variability.
We perform the first reverberation mapping of the Si IV and C IV emission lines for a high-luminosity quasar at high redshift with the use of 138 R-band photometric data and 30 spectra available over 16 years of observations. We also cross-correlate the C IV absorption equivalent width variations with the continuum light curve to estimate the recombination time lags of the various absorbers and infer the physical conditions of the ionised gas.
We find a reverberation-mapping time lag of ~900 rest-frame days for both Si IV and C IV emission lines. This is consistent with an extension of the BLR size-to-luminosity relation for active galactic nuclei up to a luminosity of ~10⁴⁸ erg s^-1, and implies a black hole mass of 10¹⁰ M_⊙. Additionally, we measure a recombination time lag of ~160 days in the rest frame for the C IV narrow absorption system, which implies an electron density of the absorbing gas of ~2.5 × 10⁴ cm^-3.
The measured black hole mass of APM 08279+5255 indicates that the quasar resides in an under-massive host-galaxy bulge with M_bulge ~7.5 M_BH, and that the lens magnification is lower than ~8. Finally, the inferred electron density of the narrow-line absorber implies a distance of the order of 10 kpc of the absorbing gas from the quasar, placing it within the host galaxy.

Accepted by A&A

E-mail contact: saturnfg@roma1.infn.it
Preprint available at: http://arxiv.org/abs/1512.03195

Radio galaxies in ZFOURGE/NMBS: no difference in the properties of massive galaxies with and without radio-AGN out to z=2.25

G. A. Rees^1,2, L. R. Spitler^1,3, R. P. Norris², M. J. Cowley^1,3, C. Papovich^4,5, K. Glazebrook⁶, R. F. Quadri^4,5, C. M. S. Straatman⁷, R. Allen^3,6, G. G. Kacprzak⁶, I. Labbe⁷, T. Nanayakkara⁶, A. R. Tomczak^4,5, K.-V. Tran^4,5

1. Macquarie University, Balaclava Road, Epping, NSW, Australia
2. CSIRO Australia Telescope National Facility, PO Box 76, Epping, NSW, 1710, Australia
3. Australian Astronomical Observatories, PO Box 915 North Ryde NSW 1670, Australia
4. George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A&M University, College Station, TX, 77843-4242 USA
5. Department of Physics and Astronomy, Texas A&M University, College Station, TX, 77843-4242 USA
6. Centre for Astrophysics & Supercomputing, Swinburne University, Hawthorn, VIC 3122, Australia
7. Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands

In order to reproduce the high-mass end of the galaxy mass-distribution, some process must be responsible for the suppression of star-formation in the most massive of galaxies. Commonly Active Galactic Nuclei (AGN) are invoked to fulfil this role, but the exact means by which they do so is still the topic of much debate, with studies finding evidence for both the suppression and enhancement of star-formation in AGN hosts. Using the ZFOURGE and NMBS galaxy surveys, we investigate the host galaxy properties of a mass-limited (M ≥ 10^10.5 M_⊙), high-luminosity (L_1.4 > 10²⁴ W Hz^-1) sample of radio-loud Active Galactic Nuclei to a redshift of z = 2.25. In contrast to low redshift studies, which associate radio-AGN activity with quiescent hosts, we find that the majority of z>1.5 radio-AGN are hosted by star-forming galaxies. Indeed, the stellar populations of radio-AGN are found to evolve with redshift in a manner that is consistent with the non-AGN mass-similar galaxy population. Interestingly, we find the radio-AGN fraction is constant across a redshift range of 0.25 ≤ z < 2.25, perhaps indicating that the radio-AGN duty cycle has little dependence on redshift or galaxy type. We do however see a strong relation between the radio-AGN fraction and stellar mass, with radio-AGN becoming rare below ~10^10.5 M_⊙ or a halo-mass of 10¹² M_⊙. This halo-mass threshold is in good agreement with simulations that initiate radio-AGN feedback at this mass limit. Despite this we find that radio-AGN host star-formation rates are consistent with the non-AGN mass-similar galaxy sample, suggesting that while radio-AGN are in the right place to suppress star-formation in massive galaxies they are not necessarily responsible for doing so.

Accepted by Monthly Notices of the Royal Astronomical Society DOI: http://dx.doi.org/10.1093/mnras/stv2468

E-mail contact: glen.rees@students.mq.edu.au
Preprint available at: http://arxiv.org/abs/1511.01988

The ionised X-ray outflowing torus in ESO323-G77 : low-ionisation clumps confined by homogeneous warm absorbers

Mario Sanfrutos¹, Giovanni Miniutti¹, Yair Krongold², Beatriz Agís-González¹ and Anna Lia Longinotti^{2, 3, 4}

1. Centro de Astrobiología (CSIC-INTA), Dep. de Astrofísica; ESAC, PO Box 78, Villanueva de la Cañada, E-28691 Madrid, Spain
2. Instituto de Astronomía, Universidad Nacional Autónoma de México, Apdo. 70-264, Cd. Universitaria, México DF 04510, México
3. European Space Astronomy Centre of ESA P.O. Box 78, Villanueva de la Cañada, E-28691 Madrid, Spain
4. Catedrática CONACYT - Instituto Nacional de Astrofísica, Óptica y Electrónica, Luis E. Erro 1, Tonantzintla, Puebla, México, C.P. 72840

We report on the long- and short-term X-ray spectral analysis of the polar-scattered Seyfert1.2 galaxy ESO323-G77, observed in three epochs between 2006 and 2013 with Chandra and XMM-Newton. Four high-resolution Chandra observations give us a unique opportunity to study the properties of the absorbers in detail, as well as their short time-scale (days) variability. From the rich set of absorption features seen in the Chandra data, we identify two warm absorbers with column densities and ionisations that are consistent with being constant on both short and long time-scales, suggesting that those are the signature of a rather homogeneous and extended outflow. A third absorber, ionised to a lesser degree, is also present and it replaces the strictly neutral absorber that is ubiquitously inferred from the X-ray analysis of obscured Compton-thin sources. This colder absorber appears to vary in column density on long time-scales, suggesting a non-homogeneous absorber. Moreover, its ionisation responds to the nuclear luminosity variations on time-scales as short as a few days, indicating that the absorber is in photoionisation equilibrium with the nuclear source on these time-scales. All components are consistent with being co-spatial and located between the inner and outer edges of the so-called dusty, clumpy torus. Assuming co-spatiality, the three phases also share the same pressure, suggesting that the warm/hot phases confine the colder, most likely clumpy, medium. We discuss further the properties of the outflow in comparison with the lower resolution XMM-Newton data.

Accepted by MNRAS

E-mail contact: sanfrutoscm@cab.inta-csic.es
Preprint available at: http://arxiv.org/abs/1512.06631

The case for inflow of the broad-line region of active galactic nuclei

C. Martin Gaskell¹ and René W. Goosmann²

1. Department of Astronomy and Astrophysics, University of California at Santa Cruz, Santa Cruz, CA 95064, USA
2. Observatoire astronomique de Strasbourg, Universit?? de Strasbourg, CNRS, UMR 7550, 11 rue de l???Université, F-67000 Strasbourg, France

The high-ionization lines of the broad-line region (BLR) of thermal active galactic nuclei (AGNs) show blueshifts of a few hundred km/s to several thousand km/sec with respect to the low-ionization lines. This has long been thought to be due to the high-ionization lines of the BLR arising in a wind of which the far side of the outflow is blocked from our view by the accretion disc. Evidence for and against the disc-wind model is discussed. The biggest problem for the model is that velocity-resolved reverberation mapping repeatedly fails to show the expected kinematic signature of outflow of the BLR. The disc-wind model also cannot readily reproduce the red side of the line profiles of high-ionization lines. The rapidly falling density in an outflow makes it difficult to obtain high equivalent widths. We point out a number of major problems with associating the BLR with the outflows producing broad absorption lines. An explanation which avoids all these problems and satisfies the constraints of both the line profiles and velocity-resolved reverberation-mapping is a model in which the blueshifting is due to scattering off material spiraling inwards with an inflow velocity of half the velocity of the blueshifting. We discuss how recent reverberation mapping results are consistent with the scattering-plus-inflow model but do not support a disc-wind model. We propose that the anti-correlation of the apparent redshifting of Hβ with the blueshifting of CIV is a consequence of contamination of the red wings of Hβ by the broad wings of [OIII].

Accepted for special issue of Astrophysics and Space Science, "Spectral Line Shapes in Astrophysics".

E-mail contact: mgaskell@ucsc.edu
Preprint available at: http://adsabs.harvard.edu/abs/2015arXiv151208900G

The case for cases B and C: intrinsic hydrogen line ratios of the broad-line region of active galactic nuclei, reddenings, and accretion disc sizes

C. Martin Gaskell¹

1. Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064

Low-redshift active galactic nuclei (AGNs) with extremely blue optical spectral indices are shown to have a mean, velocity-averaged, broad-line Hα/Hβ ratio of ≈2.72±0.04, consistent with the Baker-Menzel Case B value. Comparison of a wide range of properties of the very bluest AGNs with those of a luminosity-matched subset of the Dong et al. blue AGN sample indicates that the only difference is the internal reddening. Ultraviolet fluxes are brighter for the bluest AGNs by an amount consistent with the flat AGN reddening curve of Gaskell et al. (2004). The lack of a significant difference in the GALEX (FUV-NUV) colour index strongly rules out a steep SMC-like reddening curve and also argues against an intrinsically harder spectrum. For very blue AGNs the Lyα/Hβ ratio is also consistent with being the Case B value. The Case B ratios provide strong support for the self-shielded broad-line model of Gaskell, Klimek & Nazarova. It is proposed that the greatly enhanced Lyα/Hβ ratio at very high velocities is a consequence of continuum fluorescence in the Lyman lines (Case C).
Reddenings of AGNs mean that the far-UV luminosity is underestimated by an order of magnitude. This will be the main cause of the discrepancies between measured accretion disc sizes and the predictions of simple accretion disc theory. The greater luminosity of AGNs also resolves the photon underproduction problem for the intergalactic medium. The total mass in lower mass supermassive black holes must be greater than hitherto estimated.

Submitted to Monthly Notices of the Royal Astronomical Society

E-mail contact: mgaskell@ucsc.edu
Preprint is available at http://adsabs.harvard.edu/abs/2015arXiv151209291G

X-ray/UV variability and the origin of soft X-ray excess emission from II Zw 177

Main Pal¹, Gulab C. Dewangan¹, Ranjeev Misra¹, Pramod K. Pawar²

1. Inter University Centre for Astronomy and Astrophysics, Pune 411 007, India
2. Swami Ramanand Teerth Marathwada University, Nanded, India

We study X-ray and UV emission from the narrow-line Seyfert 1 galaxy II Zw 177 using a 137 ks long and another 13 ks short XMM observation performed in 2012 and 2001, respectively. Both observations show soft X-ray excess emission contributing 76.9±4.9% in 2012 and 58.8±10.2% in 2001 in the 0.3-2 kev band. We find that both blurred reflection from an ionized disc and Comptonized disc emission describe the observed soft excess well. Time-resolved spectroscopy on scales of ∼20ks reveals strong correlation between the soft excess and the powerlaw components. The fractional variability amplitude F_var derived from EPIC-pn lightcurves at different energy bands is nearly constant (F_var∼20%). This is in contrast to other AGNs where the lack of short term variation in soft X-ray excess emission has been attributed to intense light bending in the framework of the "lamppost" model. Thus, the variations in powerlaw emission are most likely intrinsic to corona rather than just due to the changes of height of compact corona. The variable UV emission (F_var∼1%) is uncorrelated to any of the X-ray components on short timescales suggesting that the UV emission is not dominated by the reprocessed emission. The gradual observed decline in the UV emission in 2012 may be related to the secular decline due to the changes in the accretion rate. In this case, the short term X-ray variability is not due to the changes in the seed photons but intrinsic to the hot corona.

Accepted by MNRAS

E-mail contact: mainpal@iucaa.in
Preprint available at: http://arxiv.org/abs/1601.00503

Jobs

Research Fellow in Radiative Hydrodynamics
University of Southampton, UK
Deadline: 1st February 2016

Email contact: s.hoenig@soton.ac.uk
Further Information: https://jobs.soton.ac.uk/Vacancy.aspx?ref=665515WF

The Astrogroup of the University of Southampton's Department of Physics & Astronomy invites applications for a postdoctoral research fellow in the field of hydrodynamical simulations. You will be joining an ambitious team and work with Dr Sebastian Hoenig on an ERC-funded effort to develop a new radiative hydrodynamical model of the dusty environment of active galactic nuclei (AGN).

Applications are welcome from both junior and more senior researchers with a background in hydrodynamical modelling and experience with state-of-the-art public SPH and/or moving mesh/adaptive mesh refinement codes. Previous experience with AGN is an asset, but not required.

The Southampton Astrogroup provides a stimulating and collegial environment with many opportunities to collaborate with other group members. Our main research themes are compact objects and time-domain astrophysics. We are strongly committed to diversity in the student and academic population and you will be supported in developing your career while maintaining a good work-life balance through family-friendly policies. The position will provide you with time and resources to explore and develop independent research.

The post is initially for two years, with annual extensions up to 4 years depending on performance. Arrangements for more senior candidates are negotiable. The appointment will be full time on University of Southampton Level 4 (£28,982 - £35,609 commensurate to experience). In addition, the University offers an attractive benefits package and relocation assistance. A starting date of 1 July 2016 is targeted but earlier or later dates can be discussed.

If you are interested, please apply via the university's job portal (reference: 665515WF). Applications submitted by 1 February 2016 will receive full consideration, but the position remains open until filled.

Applications should consist of a cover letter, CV, publication list, and a brief statement of research interested (2 pages max). Please upload all documents as one pdf file. Moreover, three letters of reference are required with contact details to be provided on application (letter requests will be sent automatically by the application system).

Informal inquiries are particularly welcome. Please contact Dr Sebastian Hoenig, s.hoenig@soton.ac.uk (Twitter: @dustrophysix).

Research Fellow in Observational Astrophysics
University of Southampton, UK
Deadline: 1st February 2016

Email contact: s.hoenig@soton.ac.uk
Further Information: https://jobs.soton.ac.uk/Vacancy.aspx?ref=665315WF

The Astrogroup of the University of Southampton's Department of Physics & Astronomy invites applications for a postdoctoral research fellow in high-resolution infrared/sub-mm studies of active galactic nuclei. You will be joining an ambitious team and work with Dr Sebastian Hoenig on an ERC-funded effort to spatially resolve the circumnuclear environment of AGN and constrain its kinematics and physical properties. New ALMA and VLT Interferometer data of nearby AGN are the main focus of the project to which you will be contributing.

Applications are welcome from both junior and more senior researchers with experience in infrared/sub-mm observations, interferometry, and/or advanced image processing. Previous work on AGN is an asset, but not required.

The post is initially for two years and can be extended depending on performance. The appointment will be full time on University of Southampton Level 4 (??28,982 - ??35,609 commensurate to experience). In addition, the University offers an attractive benefits package and relocation assistance. A starting date of 1 July 2016 is targeted but earlier or later dates can be discussed.

If you are interested, please apply via the university's job portal (reference: 665315WF) (see link above). Applications submitted by 1 February 2016 will receive full consideration, but the position remains open until filled.

Informal inquiries are particularly welcome. Please contact Dr Sebastian Hoenig, s.hoenig@soton.ac.uk (Twitter: @dustrophysix).

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