QSO2 outflow characterization using data obtained with OSIRIS at the Gran Telescopio Canarias

Context. Ionized outflows are ubiquitous in non-radio-loud obscured quasars (QSO2s) at different redshifts. However, the actual size of the outflows and their efficiency for gas ejection and star formation truncation are controversial. Large-scale (exceeding several kiloparsec) extended radio structures might be necessary to identify (even to trigger) outflow signatures across such large spatial scales. Aims. We search for large-scale ionized outflows associated with six optically selected QSO2 (five non-radio-loud and one radio-loud) at z ∼ 0.2−0.5, targeting objects with extended radio structures. We also investigate the dynamical state of the QSO2 host galaxies. Methods. We obtained data with the optical imager and long-slit spectrograph (OSIRIS) mounted on the 10.4m Gran Telescopio Canarias Spanish telescope (GTC) for these six QSO2 with the slit located along the radio axis. We traced the gas kinematics with the [OIII]λλ4959,5007 lines to investigate ionized outflows and characterize the dynamical state of the host galaxies. This second study was complemented with previously published spectroscopic data obtained with the multimode focal reducer and low dispersion spectrograph (FORS2) mounted on the Very Large Telescope (VLT) of 13 more QSO2 at similar z. Results. We identify ionized outflows in four out of the six QSO2 observed with the GTC. The outflows are spatially unresolved in two QSO2 and compact in a third (radial size of R = 0.8 ± 0.3 kpc). Of particular interest is the radio-quiet QSO2 SDSS 0741+3020 at z = 0.47. It is associated with a giant ∼112 kpc nebula. An ionized outflow probably induced by the radio structures has been detected along the axis defined by the central ∼1″ radio structure, extending up to at least ∼4 kpc from the active galactic nucleus (AGN). Turbulent gas (σ ∼ 130 km s−1) has also been detected across the giant gas nebula up to ∼40 kpc from the AGN. This turbulence may have been induced by outflows triggered by the interaction between a so-far undetected large-scale radio source and the nebula. Regarding the dynamical state of the host galaxies, we find that the majority of the QSO2 show v/σ < 1, implying that they are dominated by random motions (so-called dispersion-dominated systems). Most (17 of 19) fall in the area of the E/S0 galaxies in the dynamical diagram v/σ versus σ. None are consistent with spiral or disk galaxies.

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Patterns of floral morphology in relation to climate and floral visitors

Annals of Botany ◽

10.1093/aob/mcz172 ◽

2019 ◽

Vol 125 (3) ◽

pp. 433-445 ◽

Cited By ~ 2

Author(s):

Urs K Weber ◽

Scott L Nuismer ◽

Anahí Espíndola

Keyword(s):

Structural Equation ◽

Large Scale ◽

Floral Morphology ◽

Spatial Scales ◽

Climatic Conditions ◽

Climatic Data ◽

Floral Variation ◽

Floral Visitors ◽

Using Data ◽

Pollinator Fauna

Abstract Background and Aims The diversity of floral morphology among plant species has long captured the interest of biologists and led to the development of a number of explanatory theories. Floral morphology varies substantially within species, and the mechanisms maintaining this diversity are diverse. One possibility is that spatial variation in the pollinator fauna drives the evolution of spatially divergent floral ecotypes adapted to the local suite of pollinators. Another possibility is that geographic variation in the abiotic environment and local climatic conditions favours different floral morphologies in different regions. Although both possibilities have been shown to explain floral variation in some cases, they have rarely been competed against one another using data collected from large spatial scales. In this study, we assess floral variation in relation to climate and floral visitors in four oil-reward-specialized pollination interactions. Methods We used a combination of large-scale plant and pollinator samplings, morphological measures and climatic data. We analysed the data using spatial approaches, as well as traditional multivariate and structural equation modelling approaches. Key Results Our results indicate that the four species have different levels of specialization, and that this can be explained by their climatic niche breadth. In addition, our results show that, at least for some species, floral morphology can be explained by the identity of floral visitors, with climate having only an indirect effect. Conclusions Our results demonstrate that, even in very specialized interactions, both biotic and abiotic variables can explain a substantial amount of intraspecific variation in floral morphology.

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Bent It Like FRs: Extended Radio AGN in the COSMOS Field and Their Large-Scale Environment

Galaxies ◽

10.3390/galaxies9040093 ◽

2021 ◽

Vol 9 (4) ◽

pp. 93

Author(s):

Eleni Vardoulaki ◽

Franco Vazza ◽

Eric F. Jiménez-Andrade ◽

Ghassem Gozaliasl ◽

Alexis Finoguenov ◽

...

Keyword(s):

Large Scale ◽

Ambient Medium ◽

Adaptive Mesh ◽

Radio Structure ◽

X Ray ◽

Galaxy Groups ◽

Extended Radio ◽

Wide Range ◽

Jet Interactions ◽

Host Properties

A fascinating topic in radio astronomy is how to associate the complexity of observed radio structures with their environment in order to understand their interplay and the reason for the plethora of radio structures found in surveys. In this project, we explore the distortion of the radio structure of Fanaroff–Riley (FR)-type radio sources in the VLA-COSMOS Large Project at 3 GHz and relate it to their large-scale environment. We quantify the distortion by using the angle formed between the jets/lobes of two-sided FRs, namely bent angle (BA). Our sample includes 108 objects in the redshift range 0.08<z<3, which we cross-correlate to a wide range of large-scale environments (X-ray galaxy groups, density fields, and cosmic web probes) in the COSMOS field. The median BA of FRs in COSMOS at zmed∼0.9 is 167.5−37.5+11.5 degrees. We do not find significant correlations between BA and large-scale environments within COSMOS covering scales from a few kpc to several hundred Mpc, nor between BA and host properties. Finally, we compare our observational data to magnetohydrodynamical (MHD) adaptive-mesh simulations ENZO-MHD of two FR sources at z = 0.5 and at z = 1. Although the scatter in BA of the observed data is large, we see an agreement between observations and simulations in the bent angles of FRs, following a mild redshift evolution with BA. We conclude that, for a given object, the dominant mechanism affecting the radio structures of FRs could be the evolution of the ambient medium, where higher densities of the intergalactic medium at lower redshifts as probed by our study allow more space for jet interactions.

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Linking gas and galaxies at high redshift: MUSE surveys the environments of six damped Lyα systems at z ≈ 3

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1501 ◽

2019 ◽

Vol 487 (4) ◽

pp. 5070-5096 ◽

Cited By ~ 12

Author(s):

Ruari Mackenzie ◽

Michele Fumagalli ◽

Tom Theuns ◽

David J Hatton ◽

Thibault Garel ◽

...

Keyword(s):

Large Scale ◽

High Redshift ◽

Large Telescope ◽

Host Galaxies ◽

High Confidence ◽

High Detection Rate ◽

Very Large Telescope ◽

High Detection ◽

Impact Parameters ◽

Characteristic Mass

ABSTRACT We present results from a survey of galaxies in the fields of six z ≥ 3 damped Lyman α (Lyα) systems (DLAs) using the Multi Unit Spectroscopic Explorer (MUSE) at the Very Large Telescope (VLT). We report a high detection rate of up to ${\approx } 80{{\ \rm per\ cent}}$ of galaxies within 1000 km s−1 from DLAs and with impact parameters between 25 and 280 kpc. In particular, we discovered five high-confidence Lyα emitters associated with three DLAs, plus up to nine additional detections across five of the six fields. The majority of the detections are at relatively large impact parameters (>50 kpc) with two detections being plausible host galaxies. Among our detections, we report four galaxies associated with the most metal-poor DLA in our sample (Z/Z⊙ = −2.33 ± 0.22), which trace an overdense structure resembling a filament. By comparing our detections with predictions from the Evolution and Assembly of GaLaxies and their Environments (EAGLE) cosmological simulations and a semi-analytic model designed to reproduce the observed bias of DLAs at z > 2, we conclude that our observations are consistent with a scenario in which a significant fraction of DLAs trace the neutral regions within haloes with a characteristic mass of $M_{\rm h} \approx 10^{11}-10^{12}~\rm M_\odot$, in agreement with the inference made from the large-scale clustering of DLAs. We finally show how larger surveys targeting ≈25 absorbers have the potential of constraining the characteristic masses of haloes hosting high-redshift DLAs with sufficient accuracy to discriminate between different models.

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Stellar Populations of Kinematically Decoupled Cores in E/S0 Galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306005540 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 122-122

Author(s):

Richard M. McDermid ◽

Eric Emsellem ◽

Kristen L. Shapiro ◽

Roland Bacon ◽

Martin Bureau ◽

...

Keyword(s):

Large Scale ◽

Small Sample Size ◽

Abundance Ratio ◽

Small Sample ◽

Gas Kinematics ◽

Integral Field Spectroscopy ◽

Counter Rotation ◽

Central Regions ◽

S0 Galaxies ◽

Line Strengths

AbstractIn this poster contribution, we present results from high spatial resolution integral-field spectroscopy of elliptical (E) and lenticular (S0) galaxies from the SAURON representative survey, obtained with the OASIS and GMOS spectrographs. These seeing-limited observations explore the central ∼10''10″ (typically one kiloparsec diameter) regions of these galaxies using a spatial sampling four times higher than SAURON (0″27 vs. 0″94 spatial elements), resulting in almost a factor of two improvement in the median PSF. These data allow accurate study of the central regions to complement the large-scale view provided by SAURON. We derive the stellar and gas kinematics, stellar absorption-line strengths and nebular emission-line strengths for our sample, and derive maps of the luminosity-weighted stellar age, metallicity and abundance ratio via stellar population models. From these data we find a wealth of structures either not seen or poorly resolved in the SAURON data, including a number of kinematically-decoupled cores (KDCs) in the centres of some galaxies. We compare the intrinsic size and luminosity-weighted stellar age of all the visible KDCs in the full SAURON sample, and find two types of components: kiloparsec-scale KDCs, which are older than 8 Gyr, and are found in galaxies with little net rotation; and compact KDCs, which have intrinsic diameters of less than a few hundred parsec, show a range of stellar ages from 0.5 - 15 Gyr (with 5/6 younger than 5 Gyr), are found exclusively in fast-rotating galaxies, and are close to counter-rotating around the same axis as their host. Of the 7 galaxies in the SAURON sample with integrated luminosity-weighted ages less than 5 Gyr, 5 show such compact KDCs, suggesting a link between counter-rotation and recent star-formation. We show that this may be partly due to a combination of small sample size at young ages, and an observational bias, since young KDCs are easier to detect than their older and/or co-rot ating counterparts.

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J1110+4817 – a compact symmetric object candidate revisited

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1669 ◽

2020 ◽

Vol 496 (2) ◽

pp. 1811-1818 ◽

Cited By ~ 1

Author(s):

Máté Krezinger ◽

Sándor Frey ◽

Tao An ◽

Sumit Jaiswal ◽

Yingkang Zhang

Keyword(s):

Large Scale ◽

Galactic Nuclei ◽

Host Galaxy ◽

Nuclear Activity ◽

Radio Structure ◽

Long Baseline ◽

Extended Radio ◽

Evolutionary Phase ◽

Resolution Imaging ◽

Jet Structure

ABSTRACT Compact symmetric objects (CSOs) are radio-emitting active galactic nuclei (AGNs) typically with a double-lobed radio structure confined to within 1 kpc. CSOs represent the earliest evolutionary phase of jetted AGNs. Some of them may eventually evolve into large-scale extended double sources, while others stall within the host galaxy and die out, depending on the longevity of nuclear activity, the jet power, and parameters of the surrounding galactic environment. Studying CSOs is a useful tool for understanding the evolution of the galaxies and the interactions between the jets and the medium of the host galaxy. Based on milliarcsec-resolution imaging observations using very long baseline interferometry (VLBI), it is not always straightforward to distinguish between a compact double-lobed or a core–jet structure. The quasar J1110+4817 was considered a CSO candidate in the literature earlier, but because of the lack of clear evidence, it could not be securely classified as a CSO. Here we present a comprehensive analysis of archival multifrequency VLBI observations combined with accurate Gaia optical astrometric information. Lower frequency VLBI images reveal an extended radio feature nearly perpendicular to the main structural axis of the source, apparently emanating from the brighter northern feature, which is rare among the known CSOs. While the presence of a binary AGN system cannot be fully excluded, the most plausible explanation is that J1110+4817 is a CSO.

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Different Types of Radio Sources and Possible Evolution of Radio Galaxies

International Astronomical Union Colloquium ◽

10.1017/s0252921100030906 ◽

2002 ◽

Vol 184 ◽

pp. 301-303

Author(s):

Gabriel A. Ohanian

Keyword(s):

Radio Source ◽

Large Scale ◽

Large Range ◽

Host Galaxy ◽

Radio Sources ◽

Powerful Radio ◽

Host Galaxies ◽

Radio Structure ◽

Different Types ◽

The Universe

Extragalactic radio sources have been studied for many years, but it is still unclear how they are formed and evolve. The sizes of the most powerful radio emitters in the Universe vary from less than one parsec to more than 1 Mpc. This large range of sizes has been interpreted as evidence for the evolution of the linear sizes of radio structure (e.g., O’Dea and Baum, 1997). A crucial element in the study of their evolution is the identification of the young compact counterparts of “old” FRI/FRII extended objects. Good candidates for young radio sources are those with peaked spectra (Gigahertz Peaked Spectrum - GPS and Compact Steep Spectrum - CSS, e.g., O’Dea 1998). Radio sources are presumably born in the very compact GPS phase, then they expand beyond 1 kpc into the CSS regime and finally, they reach a size of 20 kpc, and afterwards evolve into large-scale radio sources (young scenario, e.g., O’Dea 1998). Alternatively, GPS sources may be compact because a particularly dense environment prevents them from growing larger (old scenario, e.g., O’Dea 1998). In either scenario, the radio source host galaxy determines the time evolution of the radio structure. By studying the optical environments and host galaxies we hope to obtain clues to the evolution of the radio sources. Similarities or differences in host galaxy properties over a range of radio source types and sizes enable us to investigate possible differences or similarities of the radio size class as a whole.

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Student Perceptions of Community: A Different Perspective

NASPA Journal ◽

10.2202/0027-6014.1064 ◽

1998 ◽

Vol 35 (4) ◽

Author(s):

Jackie Clark ◽

Joan Hirt

Keyword(s):

Student Perceptions ◽

Large Scale ◽

Research University ◽

Small Scale ◽

Social Environments ◽

Common Assumption ◽

Small Communities ◽

Public Research University ◽

The Common ◽

Using Data

The creation of small communities has been proposed as a way of enhancing the educational experience of students at large institutions. Using data from a survey of students living in large and small residences at a public research university, this study does not support the common assumption that small-scale social environments are more conducive to positive community life than large-scale social environments.

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Ionized gas kinematics of massive elliptical galaxies in CALIFA and in cosmological zoom-in simulations

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936441 ◽

2020 ◽

Vol 635 ◽

pp. A41

Author(s):

Jan Florian ◽

Bodo Ziegler ◽

Michaela Hirschmann ◽

Polychronis Papaderos ◽

Ena Choi ◽

...

Keyword(s):

Radial Profile ◽

Major Axis ◽

Velocity Fields ◽

Host Galaxies ◽

Ionized Gas ◽

Massive Galaxies ◽

Gas Kinematics ◽

Major Merger ◽

Ordered Motion ◽

Integral Field

Context. Powerful active galactic nuclei (AGN) are supposed to play a key regulatory role on the evolution of their host galaxies by shaping the thermodynamic properties of their gas component. However, little is known as to the nature and the visibility timescale of the kinematical imprints of AGN-driven feedback. Gaining theoretical and observational insights into this subject is indispensable for a thorough understanding of the AGN-galaxy coevolution and could yield empirical diagnostics for the identification of galaxies that have experienced a major AGN episode in the past. Aims. We present an investigation of kinematical imprints of AGN feedback on the warm ionized gas medium (WIM) of massive early-type galaxies (ETGs). To this end, we take a two-fold approach that involves a comparative analysis of Hα velocity fields in 123 local ETGs from the CALIFA (Calar Alto Legacy Integral Field Area Survey) integral field spectroscopy survey with 20 simulated galaxies from high-resolution hydrodynamic cosmological SPHgal simulations. The latter were resimulated for two modeling setups, one with and another without AGN feedback. Methods. In order to quantify the effects of AGN feedback on gas kinematics, we measured three parameters that probe deviations from simple regular rotation by using the kinemetry package. These indicators trace the possible presence of distinct kinematic components in Fourier space (k3, 5/k1), variations in the radial profile of the kinematic major axis (σPA), and offsets between the stellar and gas velocity fields (Δϕ). These quantities were monitored in the simulations from a redshift 3 to 0.2 to assess the connection between black hole accretion history, stellar mass growth, and the kinematical perturbation of the WIM. Results. Observed local massive galaxies show a broad range of irregularities, indicating disturbed warm gas motions, which is irrespective of being classified via diagnostic lines as AGN or not. Simulations of massive galaxies with AGN feedback generally exhibit higher irregularity parameters than without AGN feedback, which is more consistent with observations. Besides AGN feedback, other processes like major merger events or infalling gas clouds can lead to elevated irregularity parameters, but they are typically of shorter duration. More specifically, k3, 5/k1 is most sensitive to AGN feedback, whereas Δϕ is most strongly affected by gas infall. Conclusions. We conclude that even if the general disturbance of the WIM velocity is not a unique indicator for AGN feedback, irregularity parameters that are high enough to be consistent with observations can only be reproduced in simulations with AGN feedback. Specifically, an elevated value for the deviation from simple ordered motion is a strong sign for previous events of AGN activity and feedback.

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Analysis of 220 Years of Floodplain Population Dynamics in the US at Different Spatial Scales

Water ◽

10.3390/w13020141 ◽

2021 ◽

Vol 13 (2) ◽

pp. 141

Author(s):

Firoza Akhter ◽

Maurizio Mazzoleni ◽

Luigia Brandimarte

Keyword(s):

Population Dynamics ◽

Large Scale ◽

Spatial Scales ◽

National Level ◽

State Level ◽

Economic Activities ◽

Protection Measures ◽

Management Planning ◽

The Us ◽

Over Time

In this study, we explore the long-term trends of floodplain population dynamics at different spatial scales in the contiguous United States (U.S.). We exploit different types of datasets from 1790–2010—i.e., decadal spatial distribution for the population density in the US, global floodplains dataset, large-scale data of flood occurrence and damage, and structural and nonstructural flood protection measures for the US. At the national level, we found that the population initially settled down within the floodplains and then spread across its territory over time. At the state level, we observed that flood damages and national protection measures might have contributed to a learning effect, which in turn, shaped the floodplain population dynamics over time. Finally, at the county level, other socio-economic factors such as local flood insurances, economic activities, and socio-political context may predominantly influence the dynamics. Our study shows that different influencing factors affect floodplain population dynamics at different spatial scales. These facts are crucial for a reliable development and implementation of flood risk management planning.

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Insectivorous songbirds as early indicators of future defoliation by spruce budworm

Landscape Ecology ◽

10.1007/s10980-021-01300-z ◽

2021 ◽

Author(s):

Marion Germain ◽

Daniel Kneeshaw ◽

Louis De Grandpré ◽

Mélanie Desrochers ◽

Patrick M. A. James ◽

...

Keyword(s):

Large Scale ◽

Spatial Scales ◽

Spruce Budworm ◽

Detection Methods ◽

Maximum Probability ◽

Point Count ◽

Probability Of Presence ◽

Time Lagged ◽

One Year ◽

Local Sampling

Abstract Context Although the spatiotemporal dynamics of spruce budworm outbreaks have been intensively studied, forecasting outbreaks remains challenging. During outbreaks, budworm-linked warblers (Tennessee, Cape May, and bay-breasted warbler) show a strong positive response to increases in spruce budworm, but little is known about the relative timing of these responses. Objectives We hypothesized that these warblers could be used as sentinels of future defoliation of budworm host trees. We examined the timing and magnitude of the relationships between defoliation by spruce budworm and changes in the probability of presence of warblers to determine whether they responded to budworm infestation before local defoliation being observed by standard detection methods. Methods We modelled this relationship using large-scale point count surveys of songbirds and maps of cumulative time-lagged defoliation over multiple spatial scales (2–30 km radius around sampling points) in Quebec, Canada. Results All three warbler species responded positively to defoliation at each spatial scale considered, but the timing of their response differed. Maximum probability of presence of Tennessee and Cape May warbler coincided with observations of local defoliation, or provided a one year warning, making them of little use to guide early interventions. In contrast, the probability of presence of bay-breasted warbler consistently increased 3–4 years before defoliation was detectable. Conclusions Early detection is a critical step in the management of spruce budworm outbreaks and rapid increases in the probability of presence of bay-breasted warbler could be used to identify future epicenters and target ground-based local sampling of spruce budworm.

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