The Phoenix Deep Survey: The 1.4 GHz microJansky catalogue

The initial Phoenix Deep Survey (PDS) observations with the Australia Telescope Compact Array have been supplemented by additional 1.4 GHz observations over the past few years. Here we present details of the construction of a new mosaic image covering an area of 4.56 square degrees, an investigation of the reliability of the source measurements, and the 1.4 GHz source counts for the compiled radio catalogue. The mosaic achieves a 1-sigma rms noise of 12 microJy at its most sensitive, and a homogeneous radio-selected catalogue of over 2000 sources reaching flux densities as faint as 60 microJy has been compiled. The source parameter measurements are found to be consistent with the expected uncertainties from the image noise levels and the Gaussian source fitting procedure. A radio-selected sample avoids the complications of obscuration associated with optically-selected samples, and by utilising complementary PDS observations including multicolour optical, near-infrared and spectroscopic data, this radio catalogue will be used in a detailed investigation of the evolution in star-formation spanning the redshift range 0 < z < 1. The homogeneity of the catalogue ensures a consistent picture of galaxy evolution can be developed over the full cosmologically significant redshift range of interest. The 1.4 GHz mosaic image and the source catalogue are available on the web at http://www.atnf.csiro.au/~ahopkins/phoenix/ or from the authors by request.Comment: 16 pages, 11 figures, 4 tables. Accepted for publication by A

Suplementação mineral para bovinos de corte no Pantanal (Sub-região da Nhecolândia).

Os levantamentos de concentrações de minerais nas pastagens e nos tecidos de bovinos feitos em algumas sub-regiões do Pantanal indicaram ocorrência de deficiências acentuadas, principalmente de cálcio e fósforo. Baseado nesse trabalho, a Embrapa Pantanal elaborou cinco fórmulas de suplemento mineral para diferentes sub-regiões do Pantanal

Do fiscal imbalances deteriorate sovereign debt ratings ?

We use sovereign debt rating estimations from Afonso, Gomes and Rother (2009, 2011) for Fitch, Moody’s, and Standard & Poor’s, to assess to what extent the recent fiscal imbalances are being reflected on the sovereign debt notations. With macro and fiscal data up to 2010, and macro and fiscal projections, we obtain the expected rating for several OECD countries. The answer to the title question is yes, but in a diverse way for each country. Our average model predictions point to a heterogeneous behaviour of rating agencies across countries

Radio observations of the CDF-South: a possible link between radio emission and star formation in X-ray selected AGN

We explore the nature of the radio emission of X-ray selected AGN by combining deep radio (1.4GHz; 60micro-Jy) and X-ray data with multiwavelength (optical, mid-infrared) observations in the Extended Chandra Deep Field South (E-CDFS). The fraction of radio detected X-ray sources increases from 9% in the E-CDFS to 14% in the central region of this field, which has deeper X-ray coverage from the 1Ms CDFS. We find evidence that the radio emission of up to 60% of the hard X-ray/radio matched AGN is likely associated with star-formation in the host galaxy. Firstly, the mid-IR (24micron) properties of these sources are consistent with the infrared/radio correlation of starbursts. Secondly, most of them are found in galaxies with blue rest-frame optical colours (U-V), suggesting a young stellar population. On the contrary, X-ray/radio matched AGN which are not detected in the mid-infrared have red U-V colours suggesting their radio emission is associated with AGN activity. We also find no evidence for a population of heavily obscured radio-selected AGN that are not detected in X-rays. Finally, we do no confirm previous claims for a correlation between radio emission and X-ray obscuration. Assuming that the radio continuum measures star-formation, this finding is against models where the dust and gas clouds associated with circumnuclear starbursts are spherically blocking our view to the central engine.Comment: Accepted by A&

A Tale of Two Souths: microsatellite assessment of the role Portuguese Salmo salar populations play in Europe

Tese de mestrado, Biologia da Conservação, 2022, Universidade de Lisboa, Faculdade de CiênciasAtlantic salmon (Salmo salar L.) is an anadromous species with homing behaviour. Generally, individuals from this species are born in freshwater systems, migrate to feeding grounds in North Atlantic and return to their birthplace to reproduce. This reproductive isolation potentiates local adaptation. In recent years, Atlantic salmon populations in Europe have experienced great declines and are now classified as Vulnerable (VU). In Portugal, very little is known about this species, but this species is classified as Critically Endangered (CR), the highest threatened status. In this work, 14 microsatellite loci are used to assess population structure, migratory patterns and genetic diversity of 28 already identified and analysed populations (Gilbey et al., 2018), plus two additional populations, one from Galicia, Spain (Lerez River) and the other from Portuguese Minho basin (Mouro River). This is the first work to analyse Portuguese Atlantic salmon population’s genetics. The goal of the present study was to assess if the Portuguese populations were genetically distinguishable from other European populations. This work described a new Iberian genetic cluster, which is pointed out by several analysis (namely, STRUCTURE, PCoA and POPTREE2). This new group has a similar degree of differentiation from the Main European clusters as the Icelandic cluster that was described in previous works. Another important discovery described was the high relatedness among populations from Portugal and Galicia, when compared with the Asturian population, all located in the Iberian Peninsula. The genetic diversity analysis showed that the genetic uniqueness of each population is decreasing if compared to other works. The estimates of population effective size (Ne) indicate low Ne in most of the populations. It concludes that future genetic approaches to this species must consider this new Iberian cluster. On the other side, more studies must be done to fully understand the correlation between Iberian populations (in particular, northwestern coast populations and northern coast populations). It is also highlighted the necessity of management measures, for Portuguese populations since they are the most threatened populations

The Phoenix Deep Survey: spectroscopic catalog

The Phoenix Deep Survey is a multi-wavelength survey based on deep 1.4 GHz radio imaging, reaching well into the sub-100 microJy level. One of the aims of this survey is to characterize the sub-mJy radio population, exploring its nature and evolution. In this paper we present the catalog and results of the spectroscopic observations aimed at characterizing the optically ``bright'' (R<~ 21.5 mag) counterparts of faint radio sources. Out of 371 sources with redshift determination, 21% have absorption lines only, 11% show AGN signatures, 32% are star-forming galaxies, 34% show narrow emission lines that do not allow detailed spectral classification (due to poor signal-to-noise ratio and/or lack of diagnostic emission lines) and the remaining 2% are identified with stars. For the star-forming galaxies with a Balmer decrement measurement we find a median extinction of A(Ha)=1.9 mag, higher than that of optically selected samples. This is a result of the radio selection, which is not biased against dusty systems. Using the available spectroscopic information, we estimate the radio luminosity function of star-forming galaxies in two independent redshift bins at z~0.1 and 0.3 respectively. We find direct evidence for strong luminosity evolution of these systems consistent with L(1.4 GHz) ~ (1+z)^(2.7).Comment: 39 pages, 12 figures. References added, and minor changes to reflect published versio

The Phoenix Deep Survey: X-ray properties of faint radio sources

In this paper we use a 50ks XMM-Newton pointing overlapping with the Phoenix Deep Survey, a homogeneous radio survey reaching muJy sensitivities, to explore the X-ray properties and the evolution of star-forming galaxies. UV, optical and NIR photometry is available and is used to estimate photometric redshifts and spectral types for radio sources brighter than R=21.5mag (total of 82). Sources with R<21.5mag and spiral galaxy SEDs (34) are grouped into two redshift bins with a median of z=0.240 and 0.455 respectively. Stacking analysis for both the 0.5-2 and 2-8keV bands is performed on these subsamples. A high confidence level signal (>3.5sigma) is detected in the 0.5-2keV band corresponding to a mean flux of ~3e-16cgs for both subsamples. This flux translates to mean luminosities of ~5e40 and 1.5e41cgs for the z=0.240 and 0.455 subsamples respectively. Only a marginally significant signal (2.6sigma) is detected in the 2-8keV band for the z=0.455 subsample. We argue that the stacked signal above is dominated by star-formation. The mean L_X/L_B ratio and the mean L_X of the two subsamples are found to be higher than optically selected spirals and similar to starbursts. We also find that the mean L_X and L_1.4 of the faint radio sources studied here are consistent with the L_X-L_1.4 correlation of local star-forming galaxies. Moreover, the X-ray emissivity of sub-mJy sources to z~0.3 is found to be elevated compared to local HII galaxies. The observed increase is consistent with L_X evolution of the form (1+z)^3. Assuming that our sample is indeed dominated by starbursts this is direct evidence for evolution of such systems at X-ray wavelengths. Using an empirical L_X to SFR conversion we estimate a global SFR density at z~0.3 of \~0.029M_o/yr/Mpc in agreement with previous studies.Comment: 12 pages, 6 figures, accepted for publication in MNRA

Flowing bodies: Exploring the micro and macro scales of bodily interactions with urban media installations

In this paper we investigate human interactions with urban media installations by adopting two scales of analysis: the body scale (micro) and the city scale (macro). This twofold approach allows us to better understand the relationships between the design properties of outdoor installations and the urban spatial layout around them. We conducted in-the-wild studies of two urban media installations, one consisting of fixed components, and the other of movable components, which were deployed in different places and encouraged different types of whole-body interaction. We provide a detailed account of the micro and macro levels of interactions, based on observational and qualitative explorations. Our studies reveal that the urban spatial layout is a key element in defining the interactions and encounters around outdoor interfaces, and therefore it needs to inform the design process from the outset