We present a detailed study of a peculiar source detected in the COSMOS survey at z = 0.359. Source CXOC J100043.1+020637, also known as CID-42, has two compact optical sources embedded in the same ...galaxy. The distance between the two, measured in the HST/ACS image, is 0.495" ± 0.005" that, at the redshift of the source, corresponds to a projected separation of 2.46 ± 0.02 kpc. A large (~1200 km s-1) velocity offset between the narrow and broad components of Hβ has been measured in three different optical spectra from the VLT/VIMOS and Magellan/IMACS instruments. CID-42 is also the only X-ray source in COSMOS, having in its X-ray spectra a strong redshifted broad absorption iron line and an iron emission line, drawing an inverted P-Cygni profile. The Chandra and XMM-Newton data show that the absorption line is variable in energy by ΔE = 500 eV over four years and that the absorber has to be highly ionized in order not to leave a signature in the soft X-ray spectrum. That these features—the morphology, the velocity offset, and the inverted P-Cygni profile—occur in the same source is unlikely to be a coincidence. We envisage two possible explanations, both exceptional, for this system: (1) a gravitational wave (GW) recoiling black hole (BH), caught 1-10 Myr after merging; or (2) a Type 1/Type 2 system in the same galaxy where the Type 1 is recoiling due to the slingshot effect produced by a triple BH system. The first possibility gives us a candidate GW recoiling BH with both spectroscopic and imaging signatures. In the second case, the X-ray absorption line can be explained as a BAL-like outflow from the foreground nucleus (a Type 2 AGN) at the rearer one (a Type 1 AGN), which illuminates the otherwise undetectable wind, giving us the first opportunity to show that fast winds are present in obscured active galactic nuclei (AGNs), and possibly universal in AGNs.
ABSTRACT We use the low-redshift Zurich Environmental Study (ZENS) catalog to study the dependence of the quenched satellite fraction at , and of the morphological mix of these quenched satellites, ...on three different environmental parameters: group halo mass, halo-centric distance, and large-scale structure (LSS) overdensity. Within the two mass bins into which we divide our galaxy sample, the fraction of quenched satellites is more or less independent of halo mass and the surrounding LSS overdensity, but it increases toward the centers of the halos, as found in previous studies. The morphological mix of these quenched satellites is, however, constant with radial position in the halo, indicating that the well-known morphology-density relation results from the increasing fraction of quenched galaxies toward the centers of halos. If the radial variation in the quenched fraction reflects the action of two quenching processes, one related to mass and the other to environment, then the constancy with radius of the morphological outcome suggests that both have the same effect on the morphologies of the galaxies. Alternatively, mass and environment quenching may be two reflections of a single physical mechanism. The quenched satellites have larger bulge-to-total ratios (B/T) and smaller half-light radii than the star-forming satellites. The bulges in quenched satellites have very similar luminosities and surface brightness profiles, and any mass growth of the bulges associated with quenching cannot greatly change these quantities. The differences in the light-defined B/T and in the galaxy half-light radii are mostly due to differences in the disks, which have lower luminosities in the quenched galaxies. The difference in galaxy half-light radii between quenched and star-forming satellites is however larger than can be explained by uniformly fading the disks following quenching, and the quenched disks have smaller scale lengths than in star-forming satellites. This can be explained either by a differential fading of the disks with galaxy radius or the disks being generally smaller in the past, both of which would be expected in an inside-out disk growth scenario. The overall conclusion is that, at least at low redshifts, the structure of massive quenched satellites at these masses is produced by processes that operate before the quenching takes place. A comparison of our results with semianalytic models argues for a reduction in the efficiency of group halos in quenching their disk satellites and for mechanisms to increase the B/T of low-mass quenched satellites.
We present photometric measurements for the galaxies-and when possible their bulges and disks-in the 0.05 < z < 0.0585 groups of the Zurich Environmental Study (ZENS); these measurements include (B - ...I) colors, color gradients and maps, color dispersions, as well as stellar masses and star formation rates. The ZENS galaxies are classified into quenched, moderately star-forming, and strongly star-forming using a combination of spectral features and far-UV-to-optical colors; this approach optimally distinguishes quenched systems from dust-reddened star-forming galaxies. The latter contribute up to 50% to the (B - I) "red sequence" at ~10 super(10) M sub(middot in circle). At fixed morphological or spectral type, we find that galaxy stellar masses are largely independent of environment, and especially of halo mass. As a first utilization of our photometric database, we study, at fixed stellar mass and Hubble type, how (B - I) colors, color gradients, and color dispersion of disk satellites depend on group mass M sub(GROUP), group-centric distance R/R sub(200), and large-scale structure overdensity delta sub(LSS). The strongest environmental trend is found for disk-dominated satellites with M sub(GROUP) and R/R sub(200). At M lap 10 super(10) M sub(middot in circle), disk-dominated satellites are redder in the inner regions of the groups than in the outer parts. At M gap 10 super(10) M sub(middot in circle), these satellites have shallower color gradients in higher mass groups and in the cores of groups compared with lower mass groups and the outskirts of groups. Stellar population analyses and semi-analytic models suggest that disk-dominated satellites undergo quenching of star formation in their outer disks, on timescales tau sub(quench) ~ 2 Gyr, as they progressively move inside the group potential.
In recent feminist research, women and children are not seen collectively as one marginalized group, but children and animals have been given their own research focus and categories. Judith 8:1 ...states an impressive list of forebears of Judith that defines her character and role, but scholars say nothing about the fact that she prefers to terminate this lineage by not having children or offspring, no legacy. In Judith, children are absent in the victory section, their crying out to YHWH during the period of mourning is not recognised and forgotten. Children and animals form a vulnerable group, especially in biblical narratives. In Judith 4:8- 15 and Jonah 3:6-9 at the time of a national disaster, a period of communal mourning is called by the leaders. Children and animals are given the agency to petition YHWH to intervene and not allow the crises to happen. This agency of children and animals contradicts their vulnerability as they are not involved in decision-making concerning their participation in events and overall well-being. In this paper, the agency of children and animals in Judith 4:8- 15 and Jonah 3:6-10 is critically assessed to determine if they are given a real agency to petition YHWH or if their vulnerability is exploited for communal purposes and interests. Although Judith’s role inspires feminists to focus on her independence and perseverance in saving Israel, as well as to undermine motherhood as an essential woman attribute, what has the story to say about the future and agency of children and animals, the most vulnerable in society?
Radio quasar sightlines with strong Mg II absorption lines display statistically enhanced Faraday rotation measures (RMs ), indicating the presence of additional magneto-active plasma with respect to ...sightlines free of such absorption. In this Letter, we use multi-color optical imaging to identify the galaxies likely hosting the magneto-active plasma, and to constrain the location of the latter with respect to the putative parent halo. We find that all of the sightlines with high RM pass within 50 kpc of a galaxy and that the RM distribution for low impact parameters, D < 50 kpc, is significantly different than for larger impact parameters. In addition, we find a decrease in the ratio of the polarization at 21 cm and 1.5 cm, p sub(21)/p sub(1.5), toward lower D. These two effects are most likely related, strengthen the association of excess RM with intervening galaxies, and suggest that intervening galaxies operate as inhomogeneous Faraday screens. These results are difficult to reconcile with only a disk model for the magnetic field, but are consistent with highly magnetized winds associated with Mg II systems. We infer strong magnetic fields of a few tens of mu G, consistent with the values required by the lack of evolution of the FIR-radio correlation at high redshifts. Finally, these findings lend support to the idea that the small-scale helicity bottleneck of alpha -Omega galactic dynamos can be significantly alleviated via galactic winds.
In the Letter of Jude, the author uses images from the environment to demonstrate the moral decline of the faith community. The environment is portrayed inter alia as dark, clouds without rain, trees ...without fruit, and trees uprooted. The author uses provocative or insulting language to describe the opponents of Jude as men whose appearance, behaviour or speech is typically associated with women. By linking the men with immoral women, they are effeminated. This paper examines the language used for the environment and women to depict the moral decline of the opponents in the Letter of Jude. The aim of the paper is to challenge a worldview based on the inferior status of the environment and of women, and to promote a view of the environment and women as subjects rather than substances. Ecofeminists suggest a worldview that places a high value on connection and relationship, instead of the androcentric worldview of contrast and separation.
THE zCOSMOS 20k GROUP CATALOG KNOBEL, C; LILLY, S. J; KNEIB, J.-P ...
The Astrophysical journal,
07/2012, Letnik:
753, Številka:
2
Journal Article
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We present an optical group catalog between 0.1 <, ~ z <, ~ 1 based on 16,500 high-quality spectroscopic redshifts in the completed zCOSMOS-bright survey. The catalog published herein contains 1498 ...groups in total and 192 groups with more than five observed members. The catalog includes both group properties and the identification of the member galaxies. Based on mock catalogs, the completeness and purity of groups with three and more members should be both about 83% with respect to all groups that should have been detectable within the survey, and more than 75% of the groups should exhibit a one-to-one correspondence to the "real" groups. Particularly at high redshift, there are apparently more galaxies in groups in the COSMOS field than expected from mock catalogs. We detect clear evidence for the growth of cosmic structure over the last seven billion years in the sense that the fraction of galaxies that are found in groups (in volume-limited samples) increases significantly with cosmic time. In the second part of the paper, we develop a method for associating galaxies that only have photo-z to our spectroscopically identified groups. We show that this leads to improved definition of group centers, improved identification of the most massive galaxies in the groups, and improved identification of central and satellite galaxies, where we define the former to be galaxies at the minimum of the gravitational potential wells. Subsamples of centrals and satellites in the groups can be defined with purities up to 80%, while a straight binary classification of all group and non-group galaxies into centrals and satellites achieves purities of 85% and 75%, respectively, for the spectroscopic sample.
We present a spectroscopic survey of galaxies in the COSMOS field using the Fiber Multi-object Spectrograph (FMOS), a near-infrared instrument on the Subaru Telescope. Our survey is specifically ...designed to detect the H alpha emission line that falls within the H-band (1.6-1.8 mu m) spectroscopic window from star-forming galaxies with 1.4 \textless z \textless 1.7 and M-stellar greater than or similar to 10(10) M-circle dot. With the high multiplex capability of FMOS, it is now feasible to construct samples of over 1000 galaxies having spectroscopic redshifts at epochs that were previously challenging. The high-resolution mode (R similar to 2600) effectively separates H alpha and N IIlambda 6585, thus enabling studies of the gas-phase metallicity and photoionization state of the interstellar medium. The primary aim of our program is to establish how star formation depends on stellar mass and environment, both recognized as drivers of galaxy evolution at lower redshifts. In addition to the main galaxy sample, our target selection places priority on those detected in the far-infrared by Herschel/PACS to assess the level of obscured star formation and investigate, in detail, outliers from the star formation rate (SFR)-stellar mass relation. Galaxies with Ha detections are followed up with FMOS observations at shorter wavelengths using the J-long (1.11-1.35 mu m) grating to detect H beta and O IIIlambda 5008 which provides an assessment of the extinction required to measure SFRs not hampered by dust, and an indication of embedded active galactic nuclei. With 460 redshifts measured from 1153 spectra, we assess the performance of the instrument with respect to achieving our goals, discuss inherent biases in the sample, and detail the emission-line properties. Our higher-level data products, including catalogs and spectra, are available to the community.
Bars in early- and late-type discs in COSMOS Cameron, E.; Carollo, C. M.; Oesch, P. ...
Monthly notices of the Royal Astronomical Society,
11/2010, Letnik:
409, Številka:
1
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We investigate the (large-scale) bar fraction in a mass-complete sample of M > 1010.5 M⊙ disc galaxies at 0.2 < z < 0.6 in the Cosmological Evolution Survey (COSMOS) field. The fraction of barred ...discs strongly depends on mass, disc morphology and specific star formation rate (SSFR). At intermediate stellar mass (1010.5 < M < 1011 M⊙) the bar fraction in early-type discs is much higher, at all redshifts, by a factor of ∼2, than that in late-type discs. This trend is reversed at higher stellar mass (M > 1011 M⊙), where the fraction of bars in early-type discs becomes significantly lower, at all redshifts, than that in late-type discs. The bar fractions for galaxies with low and high SSFRs closely follow those of the morphologically selected early- and late-type populations, respectively. This indicates a close correspondence between morphology and SSFR in disc galaxies at these earlier epochs. Interestingly, the total bar fraction in 1010.5 < M < 1011 M⊙ discs is built up by a factor of ∼2 over the redshift interval explored, while for M > 1011 M⊙ discs it remains roughly constant. This indicates that, already by z∼ 0.6, spectral and morphological transformations in the most massive disc galaxies have largely converged to the familiar Hubble sequence that we observe in the local Universe, while for intermediate-mass discs this convergence is ongoing until at least z∼ 0.2. Moreover, these results highlight the importance of employing mass-limited samples for quantifying the evolution of barred galaxies. Finally, the evolution of the barred galaxy populations investigated does not depend on the large-scale environmental density (at least, on the scales which can be probed with the available photometric redshifts).
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