Unveiling the faint ultraviolet Universe

AbstractWith this paper we participate to the call for ideas issued by the European Space Agency to define the Science Program and plan for space missions from 2035 to 2050. In particular we present five science cases where major advancements can be achieved thanks to space-based spectroscopic observations at ultraviolet (UV) wavelengths. We discuss the possibility to (1) unveil the large-scale structures and cosmic web in emission at redshift $\lesssim 1.7$ ≲ 1.7 ; (2) study the exchange of baryons between galaxies and their surroundings to understand the contribution of the circumgalactic gas to the evolution and angular-momentum build-up of galaxies; (3) constrain the efficiency of ram-pressure stripping in removing gas from galaxies and its role in quenching star formation; (4) characterize the progenitor population of core-collapse supernovae to reveal the explosion mechanisms of stars; (5) target accreting white dwarfs in globular clusters to determine their evolution and fate. These science themes can be addressed thanks to UV (wavelength range $\lambda \sim 90 - 350$ λ ∼ 90 − 350 nm) observations carried out with a panoramic integral field spectrograph (field of view $\sim \!1 \times 1$ ∼ 1 × 1 arcmin2), and medium spectral (R = 4000) and spatial ($\sim \!1^{\prime \prime } - 3^{\prime \prime }$ ∼ 1 ′ ′ − 3 ′ ′ ) resolution. Such a UV-optimized instrument will be unique in the coming years, when most of the new large facilities such as the Extremely Large Telescope and the James Webb Space Telescope are optimized for infrared wavelengths.

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The MURALES survey

Astronomy and Astrophysics ◽

10.1051/0004-6361/202039062 ◽

2020 ◽

Vol 645 ◽

pp. A12

Author(s):

B. Balmaverde ◽

A. Capetti ◽

A. Marconi ◽

G. Venturi ◽

M. Chiaberge ◽

...

Keyword(s):

Emission Line ◽

Large Scale ◽

Line Emission ◽

Emission Region ◽

Gas Velocity ◽

Ionized Gas ◽

Large Scale Structures ◽

Scale Structures ◽

Integral Field Spectrograph ◽

Integral Field

We present the final observations of a complete sample of 37 radio galaxies from the Third Cambridge Catalogue (3C) with redshift < 0.3 and declination < 20° obtained with the VLT/MUSE optical integral field spectrograph. These data were obtained as part of the MUse RAdio Loud Emission line Snapshot (MURALES) survey with the main goal of exploring the AGN feedback process in the most powerful radio sources. We present the data analysis and, for each source, the resulting emission line images and the 2D gas velocity field. Thanks to the unprecedented depth these observations reveal emission line regions (ELRs) extending several tens of kiloparsec in most objects. The gas velocity shows ordered rotation in 25 galaxies, but in several sources it is highly complex. We find that the 3C sources show a connection between radio morphology and emission line properties. In the ten FR I sources the line emission region is generally compact, only a few kpc in size; only in one case does it exceed the size of the host. Conversely, all but two of the FR II galaxies show large-scale structures of ionized gas. The median extent is 16 kpc with the maximum reaching a size of ∼80 kpc. There are no apparent differences in extent or strength between the ELR properties of the FR II sources of high and low gas excitation. We confirm that the previous optical identification of 3C 258 is incorrect: this radio source is likely associated with a quasi-stellar object at z ∼ 1.54.

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Some comments about observations and image processing of comet 29P/Schwassmann-Wachmann 1

International Astronomical Union Colloquium ◽

10.1017/s0252921100031493 ◽

1999 ◽

Vol 173 ◽

pp. 243-248

Author(s):

D. Kubáček ◽

A. Galád ◽

A. Pravda

Keyword(s):

Image Processing ◽

Large Scale ◽

Harvard College ◽

Oak Ridge ◽

Large Scale Structures ◽

Short Period Comet ◽

Short Period ◽

Scale Structures ◽

Harvard College Observatory ◽

Period Comet

AbstractUnusual short-period comet 29P/Schwassmann-Wachmann 1 inspired many observers to explain its unpredictable outbursts. In this paper large scale structures and features from the inner part of the coma in time periods around outbursts are studied. CCD images were taken at Whipple Observatory, Mt. Hopkins, in 1989 and at Astronomical Observatory, Modra, from 1995 to 1998. Photographic plates of the comet were taken at Harvard College Observatory, Oak Ridge, from 1974 to 1982. The latter were digitized at first to apply the same techniques of image processing for optimizing the visibility of features in the coma during outbursts. Outbursts and coma structures show various shapes.

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Large-Scale Structures in a Compressible Mixing Layer over a Cavity

AIAA Journal ◽

10.2514/1.1825 ◽

2003 ◽

Vol 41 (12) ◽

Author(s):

Jonathan Poggie ◽

Alexander J. Smits

Keyword(s):

Large Scale ◽

Mixing Layer ◽

Compressible Mixing Layer ◽

Large Scale Structures ◽

Scale Structures

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Large-scale structures predicted by linear models of wall-bounded turbulence

Journal of Physics Conference Series ◽

10.1088/1742-6596/1522/1/012006 ◽

2020 ◽

Vol 1522 ◽

pp. 012006

Author(s):

S. Symon ◽

S. J. Illingworth ◽

I. Marusic

Keyword(s):

Large Scale ◽

Linear Models ◽

Large Scale Structures ◽

Scale Structures ◽

Wall Bounded Turbulence

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The organization and control of an evolving interdependent population

Journal of The Royal Society Interface ◽

10.1098/rsif.2015.0044 ◽

2015 ◽

Vol 12 (108) ◽

pp. 20150044 ◽

Cited By ~ 5

Author(s):

Dervis C. Vural ◽

Alexander Isakov ◽

L. Mahadevan

Keyword(s):

Evolutionary Game Theory ◽

Large Scale ◽

Social Evolution ◽

Evolutionary Game ◽

Large Scale Structures ◽

External Perturbations ◽

Emergence Of Cooperation ◽

Scale Structures ◽

And Control ◽

Evolutionarily Stable

Starting with Darwin, biologists have asked how populations evolve from a low fitness state that is evolutionarily stable to a high fitness state that is not. Specifically of interest is the emergence of cooperation and multicellularity where the fitness of individuals often appears in conflict with that of the population. Theories of social evolution and evolutionary game theory have produced a number of fruitful results employing two-state two-body frameworks. In this study, we depart from this tradition and instead consider a multi-player, multi-state evolutionary game, in which the fitness of an agent is determined by its relationship to an arbitrary number of other agents. We show that populations organize themselves in one of four distinct phases of interdependence depending on one parameter, selection strength. Some of these phases involve the formation of specialized large-scale structures. We then describe how the evolution of independence can be manipulated through various external perturbations.

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