241 research outputs found
Optical and radio properties of extragalactic radio sources with recurrent jet activity
We present a sample of 74 radio sources with recurrent jet activity. The
sample consists of 67 galaxies, 2 quasars and 5 unidentified sources, selected
from the published data or are newly recognized. The sample's redshift range is
0.002 < z < 0.7 and the size of inner and outer structures varies from 0.02 to
4248 kpc. We analyse the optical and radio properties of the sample and compare
them with the characteristics of ordinary one-off FRII radio sources. With the
help of stellar population modelling, we derive black hole masses and stellar
masses of host galaxies of 35 restarting radio sources, finding that the black
hole masses in restarting radio sources are comparable to those of typical
single-cycle FRII radio sources. The obtained median values of log M are
8.58 and 8.62 M Unlike the black hole masses, the stellar masses in
restarting radio sources tend to be smaller than in the FRII sources. Although
the stellar populations of the hosts of recurrent activity sources are
dominated by old stars, a significant fraction of young stars can be observed
as well. Based on the Sloan Digital Sky Survey photometric observations, we
also analyse the morphology of the host galaxies and obtained significantly
smaller concentration indices for the restarting radio sources when compared to
the classical FRII hosts. This effect can be interpreted as a result of
frequent merger events in the history of host galaxies of restarting radio
sources.Comment: 21 pages, 17 figure
„Środowisko artystyczne w La Force du désir Krysinskiej”
Marie Krysinska’s novel, La Force du désir, for the longest time was read as a roman à clef, an ironic depiction of the Parisian artistic milieu. Krysinska, a composer, poet, and a writer, exposes a society riddled with hypocrisy. The work of art is valued not by its merits, but by its popularity or by the sex of the creator, and, consequently, a mediocre male artisan achieves recognition for his work, while a true female artist – only a compliment on her beauty. In the artistic realm, a woman is the Other, Stranger, just like those male creators who do not submit themselves to doxa. Krysinska’s novel depicts the struggle and endurance of Art and the artist, suppressed by a mediocre audience and its false idols.Powieść Marii Krysinskiej, La Force du désir, przez długi czas była czytana jako powieść z kluczem, przedstawiająca, w sposób ironiczny, paryski światek artystyczny. Krysinska, kompozytorka, poetka i pisarka, pokazuje środowisko przeżarte hipokryzją. Ocenianie twórczości nie wedle jej wartości, ale wedle uznania publiczności lub płci sprawia, iż mierny autor zdobywa uznanie dla swego tworu, prawdziwa artystka – jedynie pochwałę swej urody. Na terenie sztuki kobieta jest Innym, Obcym, tak samo jak twórcy-mężczyźni, którzy nie wpisują się w doxa. Powieść Krysinskiej pokazuje walkę i trwanie Sztuki i artysty, tłamszonych przez miernych odbiorców i ich fałszywych bogów
Constraining jet production scenarios by studies of Narrow-Line-Radio-Galaxies
We study a large sample of narrow-line radio galaxies (NLRGs) with extended
radio structures. Using 1.4 GHz radio luminosities, , narrow optical
emission line luminosities, L_{\oiii} and , as well as black
hole masses derived from stellar velocity dispersions measured from
the optical spectra obtained with the Sloan Digital Sky Survey, we find that:
(i) NLRGs cover about 4 decades of the Eddington ratio, ; (ii) strongly
correlates with ; (iii) radio-loudness, , strongly anti-correlates with . A very broad range
of the Eddington ratio indicates that the parent population of NLRGs includes
both radio-loud quasars (RLQs) and broad-line radio galaxies (BLRGs). The
correlations they obey and their high jet production efficiencies favor a jet
production model which involves the so-called 'magnetically choked' accretion
scenario. In this model, production of the jet is dominated by the
Blandford-Znajek mechanism, and the magnetic fields in the vicinity of the
central black hole are confined by the ram pressure of the accretion flow.
Since large net magnetic flux accumulated in central regions of the accretion
flow required by the model can take place only via geometrically thick
accretion, we speculate that the massive, 'cold' accretion events associated
with luminous emission-line AGN can be accompanied by an efficient jet
production only if preceded by a hot, very sub-Eddington accretion phase.Comment: 24 pages, 6 figures, published in ApJ, moderate revisions to match
the published versio
« À quoi bon se parler avec la voix quand on se peut parler avec l’âme ? » Le silence dans les textes narratifs de Marie Krysinska
Literature is filled with silence, which, being polysemic, is a medium much harder to decipher than a word, whose semantic bearing capacity is more limited. To explore silence is to try to gain access to something most intimate, something that does not want to – or cannot – appear in verbal form. In Krysinska’s selected texts one observes silence on two levels, the narrative level and the story level. In most cases, we are dealing with a communicative silence. On the story level, characters use silence as an efficient way of achieving their goals or they are forced into silence by external factors. In many cases silence is imposed on the characters, it is not their choice, for in the given situation they could not utter even a single word. On the narrative level it is the narrator who condemns characters to the role of quasi-mutes, for any statements from characters are relatively rare. The narrator does not allow them to speak freely, he uses reported speech. He exercises active control over the reader, skilfully directing their reception and forcing them to accept his point of view
« Elle peint comme elle chante... »
The large part of Marie Krysinska’s poetry is pictorial in the intrinsic way. The range of the references to painting, both explicit and implicit, is not less significant than the musical references. Being a musician, Krysinska is as well sensitive to the colours and lines, she makes one hear and see her poetic images. This ability lets her create “images en l’air” whose pictorial intensity is varying, from the impression to the ekphrasis. Through different painting references Krysinska reveals her rooting in the culture, enters into the continuum of aesthetic reflection, involves herself in a dialogue between arts – which incessantly lasts throughout the ages – on the synchronic and diachronic level. Consciousness which diffuses through the poetic-pictorial work of art is consequently complex and heterogenic, both individual and collective. Pictoriality becomes a code, cultural and emotional, which reinforces the work of imagination and lets one feel a twofold aesthetic satisfaction
M.C. La Rocca, « Sur l’image qui manque à nos jours, Pascal Quignard et l’imaginaire de l’absence », [dans :] Quêtes littéraires, 2015, no 5, p. 201-211
M.C. La Rocca, « Sur l’image qui manque à nos jours, Pascal Quignard et l’imaginaire de l’absence », [dans :] Quêtes littéraires, 2015, no 5, p. 201-21
Effect of electron correlations in Pd, Ni, and Co monowires
We investigated the effect of mean-field electron correlations on the band
electronic structure of Co, Ni, and Pd ultra-thin monatomic nanowires, at the
breaking point, by means of density-functional calculations in the
self-interaction corrected LDA approach (LDA+SIC) and alternatively by the
LDA+ scheme. We find that adding static electron correlations increases the
magnetic moment in Pd monowires, but has negligible effect on the magnetic
moment in Co and Ni. Furthermore, the number of -dominated conductance
channels decreases somewhat compared to the LDA value, but the number of
-dominated channels is unaffected, and remains equal to one per spin.Comment: to appear in PR
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