Cosmic structures leave an imprint on the microwave background radiation through the integrated Sachs–Wolfe (ISW) effect. We construct a template map of the linear signal using the Sloan Digital Sky ...Survey-III Baryon Acoustic Oscillation Survey at redshift 0.43 < z < 0.65. We verify the imprint of this map on the Planck cosmic microwave background (CMB) temperature map at the 97 per cent confidence level and show consistency with the density–temperature cross-correlation measurement. Using this ISW reconstruction as a template, we investigate the presence of ISW sources and further examine the properties of the Granett–Neyrinck–Szapudi supervoid and supercluster catalogue. We characterize the three-dimensional density profiles of these structures for the first time and demonstrate that they are significant structures. Model fits demonstrate that the supervoids are elongated along the line of sight and we suggest that this special orientation may be picked out by the void-finding algorithm in photometric redshift space. We measure the mean temperature profiles in Planck maps from public void and cluster catalogues. In an attempt to maximize the stacked ISW signal, we construct a new catalogue of superstructures based upon local peaks and troughs of the gravitational potential. However, we do not find a significant correlation between these structures and the CMB temperature.
We present the first quantitative detection of large-scale filamentary structure at z NOT approximately equal to 0.7 in the large cosmological volume probed by the VIMOS Public Extragalactic ...Redshift Survey (VIPERS). We use simulations to show the capability of VIPERS to recover robust topological features in the galaxy distribution, in particular the filamentary network. We then investigate how galaxies with different stellar masses and stellar activities are distributed around the filaments, and find a significant segregation, with the most massive or quiescent galaxies being closer to the filament axis than less massive or active galaxies. The signal persists even after downweighting the contribution of peak regions. Our results suggest that massive and quiescent galaxies assemble their stellar mass through successive mergers during their migration along filaments towards the nodes of the cosmic web. On the other hand, low-mass star-forming galaxies prefer the outer edge of filaments, a vorticity-rich region dominated by smooth accretion, as predicted by the recent spin alignment theory. This emphasizes the role of large-scale cosmic flows in shaping galaxy properties.
Euclid
is poised to survey galaxies across a cosmological volume of unprecedented size, providing observations of more than a billion objects distributed over a third of the full sky. Approximately ...20 million of these galaxies will have their spectroscopy available, allowing us to map the three-dimensional large-scale structure of the Universe in great detail. This paper investigates prospects for the detection of cosmic voids therein and the unique benefit they provide for cosmological studies. In particular, we study the imprints of dynamic (redshift-space) and geometric (Alcock–Paczynski) distortions of average void shapes and their constraining power on the growth of structure and cosmological distance ratios. To this end, we made use of the Flagship mock catalog, a state-of-the-art simulation of the data expected to be observed with
Euclid
. We arranged the data into four adjacent redshift bins, each of which contains about 11 000 voids and we estimated the stacked void-galaxy cross-correlation function in every bin. Fitting a linear-theory model to the data, we obtained constraints on
f
/
b
and
D
M
H
, where
f
is the linear growth rate of density fluctuations,
b
the galaxy bias,
D
M
the comoving angular diameter distance, and
H
the Hubble rate. In addition, we marginalized over two nuisance parameters included in our model to account for unknown systematic effects in the analysis. With this approach,
Euclid
will be able to reach a relative precision of about 4% on measurements of
f
/
b
and 0.5% on
D
M
H
in each redshift bin. Better modeling or calibration of the nuisance parameters may further increase this precision to 1% and 0.4%, respectively. Our results show that the exploitation of cosmic voids in
Euclid
will provide competitive constraints on cosmology even as a stand-alone probe. For example, the equation-of-state parameter,
w
, for dark energy will be measured with a precision of about 10%, consistent with previous more approximate forecasts.
It is well known that the probability distribution function (PDF) of galaxy density contrast is approximately lognormal; whether the PDF of mass fluctuations derived from weak lensing convergence ...(...WL) is lognormal is less well established. We derive PDFs of the galaxy and projected matter density distributions via the counts-in-cells (CiC) method. We use maps of galaxies and weak lensing convergence produced from the Dark Energy Survey Science Verification data over 139 deg2. We test whether the underlying density contrast is well described by a lognormal distribution for the galaxies, the convergence and their joint PDF. We confirm that the galaxy density contrast distribution is well modelled by a lognormal PDF convolved with Poisson noise at angular scales from 10 to 40 arcmin (corresponding to physical scales of 3-10 Mpc). We note that as ...WL is a weighted sum of the mass fluctuations along the line of sight, its PDF is expected to be only approximately lognormal. We find that the ...WL distribution is well modelled by a lognormal PDF convolved with Gaussian shape noise at scales between 10 and 20 arcmin, with a best-fitting X2/dof of 1.11 compared to 1.84 for a Gaussian model, corresponding to p-values 0.35 and 0.07, respectively, at a scale of 10 arcmin. Above 20 arcmin a simple Gaussian model is sufficient. The joint PDF is also reasonably fitted by a bivariate lognormal. As a consistency check, we compare the variances derived from the lognormal modelling with those directly measured via CiC. Our methods are validated against maps from the MICE Grand Challenge N-body simulation. (ProQuest: ... denotes formulae/symbols omitted.)
The aim of this study is to distinguish genuine cosmic voids, found in a galaxy catalog by the void finder ZOBOV–VIDE, from under-dense regions in a Poisson distribution of objects. For this purpose, ...we perform two multivariate analyses using the following physical void characteristics: volume, redshift, density contrast, minimum density, contrast significance and number of member galaxies of the void. The multivariate analyses are trained on a catalog of voids obtained from a random Poisson distribution of points, used as background, and a catalog of voids identified in a mock galaxy catalog, used as signal. The classifications are then applied to voids extracted from the Data Release 12 sample of Luminous Red Galaxies in the redshift range 0.45 ≤ z ≤ 0.7 from the Sloan Digital Sky Survey Baryon Oscillation Spectroscopic Survey (SDSS BOSS DR12 CMASS). Our results show that the resulting void catalog is nearly free of contamination by Poisson noise. We also study the effect of tracer sparsity and bias on the classification efficiencies.
We tested whether short-term nutritional supplementation (500 g lupin grain per head daily) would affect the response of ewes to the ram effect. Experiment 1 (end of non-breeding season): ewes were ...supplemented for either Days -6 to -1 relative to ram introduction (
24) or for 12 days after ram introduction (Days 11 to 22 of the ram-induced cycle;
29). Controls (
30) were not supplemented. Across all groups, 94-100% of ewes ovulated. Supplementation before ram introduction did not affect ovulation rate at the ram-induced ovulation but increased it during the ram-induced cycle (Control 1.37; supplemented 1.66;
< 0.05). Experiment 2 (the middle of non-breeding season): the supplement was fed for Days -5 to -1 relative to ram introduction. Again, supplementation did not increase number ovulating (Control 16/29; Supplemented 10/29) but it did increase ovulation rate at the ram-induced ovulation (Control 1.31; Supplemented 1.68;
< 0.05). In neither experiment did supplementation affect the frequency of short cycles. Supplementation before ram introduction did not improve the percentage of ewes ovulating or reduce the frequency of short cycles (so will not improve the synchrony of lambing). However, supplementation after ram introduction can increase prolificacy.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Abstract Growing concerns about the risk of addiction to benzodiazepines have led to increasing interest in alternative therapies to treat anxiety and depression. Lavender oil ( Lavendula ...augustifolia ) is reportedly anxiolytic in a number of species but little is known about how it affects individuals that are more or less anxious when faced with a stressor. In this study, we used changes in locomotor activity and the plasma concentrations of cortisol to test whether lavender oil would reduce behavioral and endocrine correlates of anxiety in calm and nervous sheep exposed to an isolation stressor. During the non-breeding season, ‘calm’ or ‘nervous’ female sheep from the UWA temperament flock were exposed to a mask containing either 1 mL of 10% lavender oil (calm: n = 8; nervous: n = 8) or peanut oil (calm: n = 8; nervous: n = 8). After 30 min, each sheep was isolated for 5 min and then returned to the group. Blood was sampled prior to the mask, prior to isolation, 1 min and 30 min after isolation to profile changes in the plasma concentrations of cortisol. Agitation score, locomotor activity and vocalizations were recorded as correlates of anxiety associated with the isolation stressor. Irrespective of whether they were exposed to lavender oil, calm sheep had a lower agitation score (P < 0.001), crossed the central lines of the isolation box less frequently (P < 0.001), expressed fewer vocalizations (P < 0.001) and had lower plasma concentrations of cortisol immediately after isolation (P < 0.001) than nervous sheep. Exposure of calm sheep to lavender oil decreased the agitation score (P < 0.001), frequency of vocalizations (P < 0.05), decreased the number of crosses of the central lines of the isolation box (P < 0.05), and the plasma concentrations of cortisol prior to isolation (P < 0.05) (after mask application) compared to calm control sheep. Exposure of nervous sheep to lavender oil increased the frequency of vocalizations (P < 0.05), the number of sheep attempting to escape (P < 0.05) and the plasma concentrations of cortisol 30 min after isolation (P < 0.05) compared to nervous control sheep. We conclude that genetic differences in temperament determine whether lavender oil alleviates or exacerbates the behavioral and/or endocrine correlates of anxiety in sheep.
Aims.
We analyse the properties of the host galaxies of a NeV-selected sample to investigate whether and how they are affected by the AGN.
Methods.
We have selected a sample of galaxies at 0.62 <
z
... < 1.2 from the VIMOS Public Extragalactic Redshift Survey (VIPERS) and divided it in blue cloud galaxies, red passive galaxies and green valley galaxies using the NUV
r
K
diagram. Within each category, galaxies with AGN activity were identified based on the detection of the high-ionisation NeV
λ
3426 emission line. For each galaxy we derived several properties (stellar age and mass, the (
r
−
K
) colour, the OII luminosity) and compared them between active and inactive galaxies matched in stellar mass and redshift.
Results
. We find statistically significant differences in the properties between active and inactive galaxies. These differences imply that the AGN is more often found in galaxies with younger stellar populations and more recent star-forming activity than their parent samples. Interestingly, the AGN identified through the NeV
λ
3426 emission line is not commonly found by traditional AGN-selection techniques based on shallow X-ray data, mid-IR colours, and classical line diagnostic diagrams, and might thus reveal a specific evolutionary phase. The spectral analysis reveals a sub-set of AGN within the blue cloud that has spectral signatures implying a sudden suppression of star formation activity similar to post-starburst galaxies.
Conclusion
. Using the rich dataset of the large VIPERS sample we identify a novel class of active post-starburst galaxies that would be missed by traditional selection techniques. These galaxies belong to the blue cloud, but their star-formation activity has been recently suppressed, possibly by the AGN identified through the presence of the NeV
λ
3426 emission line in their spectra. Our results support the idea that AGN feedback may be responsible for halting star-formation in active blue galaxies and for their transition into the red sequence, at least in the 0.6–1.2 redshift range and for stellar masses greater than 5 × 10
10
ℳ
⊙
. Our results are based on a complete spectroscopic sample and limited by the NeV observability, and the AGN can be variable and with a relatively short duty cycle. Considering this, AGN feedback that makes blue galaxies quickly transition to the red sequence may be even more common than previously believed.
We use the unparalleled statistics of the VIPERS survey to investigate the relation between the surface mean stellar mass density Σ = ℳ/(2
π
R
e
2
) of massive passive galaxies (MPGs, ℳ ≥ 10
11
M
⊙
...) and their local environment in the redshift range 0.5 ≤
z
≤ 0.8. Passive galaxies were selected on the basis of their NUV
r
K colors (∼900 objects), and the environment was defined as the galaxy density contrast,
δ
, using the fifth nearest-neighbor approach. The analysis of Σ versus
δ
was carried out in two stellar mass bins. In galaxies with ℳ ≤ 2 × 10
11
M
⊙
, no correlation between Σ and
δ
is observed. This implies that the accretion of satellite galaxies, which is more frequent in denser environments (groups or cluster outskirts) and efficient in reducing the galaxy Σ, is not relevant in the formation and evolution of these systems. Conversely, in galaxies with ℳ > 2 × 10
11
M
⊙
, we find an excess of MPGs with low Σ and a deficit of high-Σ MPGs in the densest regions with respect to other environments. We interpret this result as due to the migration of some high-Σ MPGs (< 1% of the total population of MPGs) into low-Σ MPGs, probably through mergers or cannibalism of small satellites. In summary, our results imply that the accretion of satellite galaxies has a marginal role in the mass-assembly history of most MPGs. We have previously found that the number density of VIPERS massive star-forming galaxies (MSFGs) declines rapidily from
z
= 0.8 to
z
= 0.5, which mirrors the rapid increase in the number density of MPGs. This indicates that the MSFGs at
z
≥ 0.8 migrate to the MPG population. Here, we investigate the Σ–
δ
relation of MSFGs at
z
≥ 0.8 and find that it is consistent within 1
σ
with that of low-Σ MPGs at
z
≤ 0.8. Thus, the results of this and our previous paper show that MSFGs at
z
≥ 0.8 are consistent in terms of number and environment with being the progenitors of low-Σ MPGs at
z
< 0.8.
We present equations for the gravitational lensing flexion expected for an elliptical lens mass distribution. These can be reduced to one-dimensional finite integrals, thus saving significant ...computing time over a full two-dimensional calculation. We estimate constraints on galaxy halo ellipticities for a range of potential future surveys, finding that the constraints from the two different types of flexion are comparable and are up to two orders of magnitude tighter than those from shear. Flexion therefore appears to be a very promising potential tool for constraining the shapes of galaxy haloes from future surveys.
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