The AGN fuelling/feedback cycle in nearby radio galaxies – III. 3D relative orientations of radio jets and CO discs and their interaction

ABSTRACT This is the third paper of a series exploring the multifrequency properties of a sample of eleven nearby low-excitation radio galaxies (LERGs) in the southern sky. We are conducting an extensive study of different galaxy components (stars, dust, warm and cold gas, radio jets) with the aim of better understanding the AGN fuelling/feedback cycle in LERGs. Here, we present new, deep, sub-kpc resolution Karl G. Jansky Very Large Array (JVLA) data for five sample sources at 10 GHz. Coupling these data with previously acquired Atacama Large Millimetre/submillimetre Array (ALMA) CO(2–1) observations and measurements of comparable quality from the literature, we carry out for the first time a full 3D analysis of the relative orientations of jet and disc rotation axes in six FR I LERGs. This analysis shows (albeit with significant uncertainties) that the relative orientation angles span a wide range (≈30○–60○). There is no case where both axes are accurately aligned and there is a marginally significant tendency for jets to avoid the disc plane. Our study also provides further evidence for the presence of a jet-CO disc interaction (already inferred from other observational indicators) in at least one source, NGC 3100. In this case, the limited extent of the radio jets, along with distortions in both the molecular gas and the jet components, suggest that the jets are young, interacting with the surrounding matter and rapidly decelerating.

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Jansky VLA observations of synchrotron emitting optical hotspots of 3C 227 and 3C 445 radio galaxies

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa777 ◽

2020 ◽

Vol 494 (2) ◽

pp. 2244-2253 ◽

Cited By ~ 1

Author(s):

M Orienti ◽

G Migliori ◽

G Brunetti ◽

H Nagai ◽

F D’Ammando ◽

...

Keyword(s):

Magnetic Field ◽

Large Scale ◽

Optical Emission ◽

Position Angle ◽

Radio Galaxies ◽

Very Large Array ◽

Peculiar Characteristic ◽

Intensity Images ◽

First Time ◽

Shock Fronts

ABSTRACT We report results on deep Jansky Very Large Array (VLA) A-configuration observations at 22 GHz of the hotspots of the radio galaxies 3C 227 and 3C 445. Synchrotron emission in the optical on scales up to a few kpc was reported for the four hotspots. Our VLA observations point out the presence of unresolved regions with upper limit to their linear size of about 100 pc. This is the first time that such compact components in hotspots have been detected in a mini-sample, indicating that they are not a peculiar characteristic of a few individual hotspots. The polarization may reach values up to 70 per cent in compact (about 0.1 kpc scale) regions within the hotspot, indicating a highly ordered magnetic field with size up to a hundred parsecs. On larger scales, the average polarization of the hotspot component is about 30–45 per cent, suggesting the presence of a significant random field component, rather than an ordered magnetic field. This is further supported by the displacement between the peaks in polarized intensity and in total intensity images that is observed in all the four hotspots. The electric vector position angle is not constant, but changes arbitrarily in the central part of the hotspot regions, whereas it is usually perpendicular to the total intensity contours of the outermost edge of the hotspot structure, likely marking the large-scale shock front. The misalignment between X-ray and radio-to-optical emission suggests that the former is tracing the current particle acceleration, whereas the latter marks older shock fronts.

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Early results from a diagnostic 1.3 cm survey of massive young protostars

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312007594 ◽

2012 ◽

Vol 8 (S287) ◽

pp. 497-501

Author(s):

Crystal L. Brogan ◽

Todd R. Hunter ◽

Claudia J. Cyganowski ◽

Remy Indebetouw ◽

Rachel Friesen ◽

...

Keyword(s):

Massive Star ◽

Thermal Emission ◽

Young Stellar Objects ◽

Large Array ◽

Stellar Objects ◽

Very Large Array ◽

Early Results ◽

Wide Range ◽

First Time ◽

24 Ghz

AbstractWe have used the recently-upgraded Karl G. Jansky Very Large Array (JVLA) to conduct a K-band (~24 GHz) study of 22 massive young stellar objects in 1.3 cm continuum and a comprehensive set of diagnostic lines. This survey is unique in that it samples a wide range of massive star formation signposts simultaneously for the first time. In this proceeding we present preliminary results for the 11 sources in the 2-4 kpc distance bin. We detect compact NH3 cores in all of the fields, with many showing emission up through the (6,6) transition. Maser emission in the 25 GHz CH3OH ladder is present in 7 of 11 sources. We also detect non-thermal emission in the NH3 (3,3) transition in 7 of 11 sources.

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Systematics of Large-Scale Radio Jets

Symposium - International Astronomical Union ◽

10.1017/s0074180900027509 ◽

1982 ◽

Vol 97 ◽

pp. 121-128 ◽

Cited By ~ 4

Author(s):

Alan H. Bridle

Keyword(s):

Large Scale ◽

Radio Galaxies ◽

Radio Jets ◽

Linear Resolution ◽

Wide Range

Radio jets occur in sources with a wide range of radio luminosities, and in 70% to 80% of nearby radio galaxies. There may be two basic types of large-scale (>1 kpc) jet — B‖-dominated one-sided jets in sources with luminous radio cores, and B⊥-dominated two-sided jets in sources with weak radio cores. The large-scale jets that have been observed at high linear resolution are well collimated within a few kpc of their cores, then flare and recollimate further out. Their brightness-radius evolution is often “subadiabatic”.

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Alignment in the orientation of LOFAR radio sources

Astronomy and Astrophysics ◽

10.1051/0004-6361/202037680 ◽

2020 ◽

Vol 642 ◽

pp. A70

Author(s):

E. Osinga ◽

G. K. Miley ◽

R. J. van Weeren ◽

T. W. Shimwell ◽

K. J. Duncan ◽

...

Keyword(s):

Statistical Tests ◽

Low Frequency ◽

Radio Galaxies ◽

Three Dimensions ◽

Radio Sources ◽

3D Analysis ◽

Photometric Redshift ◽

Radio Jets ◽

Significant Alignment ◽

Using Data

Various studies have laid claim to finding an alignment of the polarization vectors or radio jets of active galactic nuclei over large distances, but these results have proven controversial and so far, there is no clear explanation for this observed alignment. To investigate this case further, we tested the hypothesis that the position angles of radio galaxies are randomly oriented in the sky by using data from the Low-Frequency Array (LOFAR) Two-metre Sky Survey (LoTSS). A sample of 7555 double-lobed radio galaxies was extracted from the list of 318 520 radio sources in the first data release of LoTSS at 150 MHz. We performed statistical tests for uniformity of the two-dimensional (2D) orientations for the complete 7555 source sample. We also tested the orientation uniformity in three dimensions (3D) for the 4212 source sub-sample with photometric or spectroscopic redshifts. Our sample shows a significant deviation from uniformity (p-value < 10−5) in the 2D analysis at angular scales of about four degrees, mainly caused by sources with the largest flux densities. No significant alignment was found in the 3D analysis. Although the 3D analysis has access to fewer sources and suffers from uncertainties in the photometric redshift, the lack of alignment in 3D points towards the cause of the observed effect being unknown systematics or biases that predominantly affect the brightest sources, although this has yet to be demonstrated irrefutably and should be the subject of subsequent studies.

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The AGN fuelling/feedback cycle in nearby radio galaxies – II. Kinematics of the molecular gas

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2368 ◽

2019 ◽

Vol 489 (3) ◽

pp. 3739-3757 ◽

Cited By ~ 2

Author(s):

Ilaria Ruffa ◽

Timothy A Davis ◽

Isabella Prandoni ◽

Robert A Laing ◽

Rosita Paladino ◽

...

Keyword(s):

Position Angle ◽

Radio Galaxies ◽

Host Galaxy ◽

Molecular Gas ◽

Gas Kinematics ◽

Radio Jets ◽

Feedback Cycle ◽

Rotation Pattern ◽

Special Cases ◽

Cold Gas

ABSTRACT This is the second paper of a series exploring the multicomponent (stars, warm and cold gas, and radio jets) properties of a sample of 11 nearby low-excitation radio galaxies, with the aim of better understanding the active galactic nuclei (AGN) fuelling/feedback cycle in these objects. Here, we present a study of the molecular gas kinematics of six sample galaxies detected in 12CO(2-1) with the Atacama Large Millimeter/submillimeter Array (ALMA). In all cases, our modelling suggests that the bulk of the gas in the observed (sub-)kpc CO discs is in ordered rotation. Nevertheless, low-level distortions are ubiquitous, indicating that the molecular gas is not fully relaxed into the host galaxy potential. The majority of the discs, however, are only marginally resolved, preventing us from drawing strong conclusions. NGC 3557 and NGC 3100 are special cases. The features observed in the CO velocity curve of NGC 3557 allow us to estimate a supermassive black hole (SMBH) mass of (7.10 ± 0.02) × 108 M⊙, in agreement with expectations from the MSMBH–σ* relation. The rotation pattern of NGC 3100 shows distortions that appear to be consistent with the presence of both a position angle and an inclination warp. Non-negligible radial motions are also found in the plane of the CO disc, likely consistent with streaming motions associated with the spiral pattern found in the inner regions of the disc. The dominant radial motions are likely to be inflows, supporting a scenario in which the cold gas is contributing to the fuelling of the AGN.

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The complete local volume groups sample – III. Characteristics of group central radio galaxies in the Local Universe

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2082 ◽

2019 ◽

Vol 489 (2) ◽

pp. 2488-2504 ◽

Cited By ~ 2

Author(s):

Konstantinos Kolokythas ◽

Ewan O’Sullivan ◽

Huib Intema ◽

Somak Raychaudhury ◽

Arif Babul ◽

...

Keyword(s):

Black Hole ◽

Radio Emission ◽

Detection Rate ◽

Very Large Array ◽

Galaxy Groups ◽

Local Volume ◽

Radio Jets ◽

Radio Detection ◽

Wide Range ◽

Poor Group

ABSTRACT Using new 610 and 235 MHz observations from the giant metrewave radio telescope (GMRT) in combination with archival GMRT and very large array (VLA) survey data, we present the radio properties of the dominant early-type galaxies in the low-richness subsample of the complete local-volume groups sample (CLoGS; 27 galaxy groups) and provide results for the radio properties of the full CLoGS sample for the first time. We find a high radio detection rate in the dominant galaxies of the low-richness subsample of 82 per cent (22/27); for the full CLoGS sample the detection rate is 87 per cent (46/53). The group-dominant galaxies exhibit a wide range of radio power, 1020–1025 W Hz−1 in the 235 and 610 MHz bands, with the majority (53 per cent) presenting point-like radio emission, 19 per cent hosting currently active radio jets, 6 per cent having remnant jets, 9 per cent being diffuse, and 13 per cent having no detected radio emission. The mean spectral index of the detected radio sources in the 235−610 MHz frequency range is found to be $\alpha _{235}^{610}\sim$0.68, and $\alpha _{235}^{1400}\sim$0.59 in the 235−1400 MHz one. In agreement with earlier studies, we find that the fraction of ultrasteep spectrum sources (α > 1.3) is ∼4 per cent, mostly dependent on the detection limit at 235 MHz. The majority of point-like systems are found to reside in dynamically young groups, whereas jet systems show no preference between spiral-rich and spiral-poor group environments. The mechanical power of the jet sources in the low-richness sample groups is estimated to be ∼1042–1044 erg s−1 with their black hole masses ranging between 2 × 108 and 5 × 109 M⊙. We confirm previous findings that while radio jet sources tend to be associated with more massive black holes, black hole mass is not the decisive factor in determining jet activity or power.

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Radio spectral properties and jet duty cycle in the restarted radio galaxy 3C388

Astronomy and Astrophysics ◽

10.1051/0004-6361/202037457 ◽

2020 ◽

Vol 638 ◽

pp. A29

Author(s):

M. Brienza ◽

R. Morganti ◽

J. Harwood ◽

T. Duchet ◽

K. Rajpurohit ◽

...

Keyword(s):

Duty Cycle ◽

Radio Galaxy ◽

Low Frequency ◽

Radio Galaxies ◽

Radio Spectrum ◽

Frequency Range ◽

Very Large Array ◽

Spatially Resolved ◽

New Generation ◽

First Time

Context. Restarted radio galaxies represent a unique tool for investigating the duty cycle of the jet activity in active galactic nuclei (AGN). The radio galaxy 3C388 has long been claimed to be a peculiar example of an AGN with multi-epoch activity because it shows a very sharp discontinuity in the GHz spectral index distribution of its lobes. Aims. We present here for the first time a spatially resolved study of the radio spectrum of 3C388 down to MHz frequencies aimed at investigating the radiative age of the source and constraining its duty cycle. Methods. We used new low-frequency observations at 144 MHz performed with the Low Frequency Array and at 350 MHz performed with the Very Large Array that we combined with archival data at higher frequencies (614, 1400, and 4850 MHz). Results. We find that the spectral indices in the lower frequency range, 144−614 MHz, have flatter values (αlow ∼ 0.55−1.14) than those observed in the higher frequency range, 1400−4850 MHz, (αhigh ∼ 0.75−1.57), but they follow the same distribution across the lobes, with a systematic steepening towards the edges. However, the spectral shape throughout the source is not uniform and often deviates from standard models. This suggests that mixing of different particle populations occurs, although it remains difficult to understand whether this is caused by observational limitations (insufficient spatial resolution and/or projection effects) or by the intrinsic presence of multiple particle populations, which might be related to the two different outbursts. Conclusions. Using single-injection radiative models, we compute that the total source age is ≲80 Myr and that the duty cycle is about ton/ttot ∼ 60%, which is enough to prevent the intracluster medium from cooling, according to X-ray estimates. While to date the radio spectral distribution of 3C388 remains a rare case among radio galaxies, multi-frequency surveys performed with new-generation instruments will soon allow us to investigate whether more sources with the same characteristics exist.

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On the Margins of Modernism

10.3366/edinburgh/9780748696369.001.0001 ◽

2017 ◽

Cited By ~ 1

Author(s):

Christopher Rosenmeier

Keyword(s):

Short Stories ◽

Detailed Analysis ◽

Chinese Literature ◽

Popular Literature ◽

Extensive Study ◽

Wide Range ◽

Chinese Fiction ◽

Scant Attention ◽

Narrative Techniques ◽

Chinese Writing

Xu Xu and Wumingshi were among the most widely read authors in China during and after the Second Sino-Japanese War (1937–1945). Despite being an integral part of the Chinese literary scene, their bestselling fiction has, however, been given scant attention in histories of Chinese writing. This book is the first extensive study of Xu Xu and Wumingshi in English or any other Western language and it re-establishes their importance within the popular Chinese literature of the 1940s. Their romantic novels and short stories were often set abroad and featured a wide range of stereotypes, from pirates, spies and patriotic soldiers to ghosts, spirits and exotic women who confounded the mostly cosmopolitan male protagonists. Christopher Rosenmeier’s detailed analysis of these popular novels and short stories shows that such romances broke new ground by incorporating and adapting narrative techniques and themes from the Shanghai modernist writers of the 1930s, notably Shi Zhecun and Mu Shiying. The study thereby contests the view that modernism had little lasting impact on Chinese fiction, and it demonstrates that the popular literature of the 1940s was more innovative than usually imagined, with authors, such as those studied here, successfully crossing the boundaries between the popular and the elite, as well as between romanticism and modernism, in their bestselling works.

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Safety assessment of biological raw materials in the system of medicines quality assurance

10.33920/med-06-2002-05 ◽

2020 ◽

pp. 63-72

Author(s):

Yu. Olefir ◽

E. Sakanyan ◽

I. Osipova ◽

V. Dobrynin ◽

M. Smirnova ◽

...

Keyword(s):

Raw Materials ◽

State Level ◽

The State ◽

Spongiform Encephalopathy ◽

Safety Standards ◽

Wide Range ◽

The Russian Federation ◽

Key Aspects ◽

First Time ◽

Medicines Quality

The entry of a wide range of biotechnological products into the pharmaceutical market calls for rein-forcement of the quality, efficacy and safety standards at the state level. The following general monographs have been elaborated for the first time to be included into the State Pharmacopoeia of the Russian Federation, XIV edition: "Viral safety" and "Reduction of the risk of transmitting animal spongiform encephalopathy via medicinal products". These general monographs were elaborated taking into account the requirements of foreign pharmacopoeias and the WHO recommendations. The present paper summarises the key aspects of the monographs.

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Innovation in Byzantine Medicine

10.1093/oso/9780198850687.001.0001 ◽

2020 ◽

Author(s):

Petros Bouras-Vallianatos

Keyword(s):

Human Physiology ◽

Medical Literature ◽

Cultural Exchange ◽

Significant Degree ◽

Medieval Medicine ◽

Medieval Latin ◽

Main Thesis ◽

Wide Range ◽

Comprehensive Examination ◽

First Time

Byzantine medicine is still a little-known and misrepresented field not only in the wider arena of debates on medieval medicine but also among Byzantinists. Byzantine medical literature is often viewed as ‘stagnant’ and mainly preserving ancient ideas; and our knowledge of it continues to be based to a great extent on the comments of earlier authorities, which are often repeated uncritically. This book presents the first comprehensive examination of the medical corpus of, arguably, the most important late Byzantine physician John Zacharias Aktouarios (c.1275–c.1330). The main thesis is that John’s medical works show an astonishing degree of openness to knowledge from outside Byzantium combined with a significant degree of originality, in particular, in the fields of uroscopy, pharmacology, and human physiology. The analysis of John’s edited (On Urines and On Psychic Pneuma) and unedited (Medical Epitome) works is supported for the first time by the consultation of a large number of manuscripts. The study is also informed by evidence from a wide range of medical sources, including previously unpublished ones, and texts from other genres, such as epistolography and merchants’ accounts. The contextualization of John’s works sheds new light on the development of Byzantine medical thought and practice, and enhances our understanding of the late Byzantine social and intellectual landscape. Finally, John’s medical observations are also examined in the light of examples from the medieval Latin and Islamic worlds, placing his medical theories in the wider Mediterranean milieu and highlighting the cultural exchange between Byzantium and its neighbours.

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