The cosmological co-evolution of supermassive black holes, AGN and galaxies

We model the cosmological co-evolution of galaxies and their central supermassive black holes (BHs) within a semi-analytical framework developed on the outputs of the Millennium Simulation (Croton et al., 2006; De Lucia & Blaizot, 2007). In this work, we analyze the model BH scaling relations, fundamental plane and mass function, and compare them with the most recent observational data. Furthermore, we extend the original code developed by Croton et al. (2006) to follow the evolution of the BH mass accretion and its conversion into radiation, and compare the derived AGN bolometric luminosity function with the observed one. We find, for the most part, a very good agreement between predicted and observed BH properties. Moreover, the model is in good agreement with the observed AGN number density in 0<z<5, provided it is assumed that the cold gas fraction accreted by BHs at high redshifts is larger than at low redshifts (Marulli et al., 2008).Comment: Proceedings of "The Central Kiloparsec: Active Galactic Nuclei and Their Hosts", Ierapetra, Crete, 4-6 June, 2008. To appear in Volume 79 of the Memorie della Societa' Astronomica Italiana. 5 pages, 4 figure

LCA to Estimate the Environmental Impact of Dairy Farms: A Case Study

Intensive farming is responsible for extreme environmental impacts under different aspects, among which global warming represents a major reason of concern. This is a quantitative problem linked to the farm size and a qualitative one, depending on farming methods and land management. The dairy sector is particularly relevant in terms of environmental impact, and new approaches to meeting sustainability goals at a global scale while meeting society's needs are necessary. The present study was carried out to assess the environmental impact of dairy cattle farms based on a life cycle assessment (LCA) model applied to a case study. These preliminary results show the possibility of identifying the most relevant impacts in terms of supplied products, such as animal feed and plastic packaging, accounting for 19% and 15% of impacts, respectively, and processes, in terms of energy and fuel consumption, accounting for 53% of impacts overall. In particular, the local consumption of fossil fuels for operations within the farm represents the most relevant item of impact, with a small margin for improvement. On the other hand, remarkable opportunities to reduce the impact can be outlined from the perspective of stronger partnerships with suppliers to promote the circularity of packaging and the sourcing of animal feed. Future studies may include the impact of drug administration and the analysis of social aspects of LCA

The miniJPAS survey : A preview of the Universe in 56 colors

The Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS) will scan thousands of square degrees of the northern sky with a unique set of 56 filters using the dedicated 2.55 m Javalambre Survey Telescope (JST) at the Javalambre Astrophysical Observatory. Prior to the installation of the main camera (4.2 deg(2) field-of-view with 1.2 Gpixels), the JST was equipped with the JPAS-Pathfinder, a one CCD camera with a 0.3 deg(2) field-of-view and plate scale of 0.23 arcsec pixel(-1). To demonstrate the scientific potential of J-PAS, the JPAS-Pathfinder camera was used to perform miniJPAS, a similar to 1 deg(2) survey of the AEGIS field (along the Extended Groth Strip). The field was observed with the 56 J-PAS filters, which include 54 narrow band (FWHM similar to 145 angstrom) and two broader filters extending to the UV and the near-infrared, complemented by the u, g, r, i SDSS broad band filters. In this miniJPAS survey overview paper, we present the miniJPAS data set (images and catalogs), as we highlight key aspects and applications of these unique spectro-photometric data and describe how to access the public data products. The data parameters reach depths of mag(AB) similar or equal to 22-23.5 in the 54 narrow band filters and up to 24 in the broader filters (5 sigma in a 3 '' aperture). The miniJPAS primary catalog contains more than 64 000 sources detected in the r band and with matched photometry in all other bands. This catalog is 99% complete at r = 23.6 (r = 22.7) mag for point-like (extended) sources. We show that our photometric redshifts have an accuracy better than 1% for all sources up to r = 22.5, and a precision of 2. The miniJPAS survey demonstrates the capability of the J-PAS filter system to accurately characterize a broad variety of sources and paves the way for the upcoming arrival of J-PAS, which will multiply this data by three orders of magnitude.Peer reviewe

Optimal dataset combining in f_nl constraints from large scale structure in an idealised case

We consider the problem of optimal weighting of tracers of structure for the purpose of constraining the non-Gaussianity parameter f_NL. We work within the Fisher matrix formalism expanded around fiducial model with f_NL=0 and make several simplifying assumptions. By slicing a general sample into infinitely many samples with different biases, we derive the analytic expression for the relevant Fisher matrix element. We next consider weighting schemes that construct two effective samples from a single sample of tracers with a continuously varying bias. We show that a particularly simple ansatz for weighting functions can recover all information about f_NL in the initial sample that is recoverable using a given bias observable and that simple division into two equal samples is considerably suboptimal when sampling of modes is good, but only marginally suboptimal in the limit where Poisson errors dominate.Comment: 6 pages, 5 figures; v2: comment on weighting for PS determination, fixed a couple of typos; v3: revised, matches version accepted by JCA

2MASS NIR photometry for 693 candidate globular clusters in M31 and the Revised Bologna Catalogue

We have identified in the 2MASS database 693 known and candidate globular clusters in M31. The 2MASS J,H,K magnitudes of these objects have been transformed to the same homogeneous photometric system of existing near infrared photometry of M31 globulars, finally yielding J,H,K integrated photometry for 279 confirmed M31 clusters, 406 unconfirmed candidates and 8 objects with controversial classification. Of these objects 529 lacked any previous estimate of their near infrared magnitudes. The newly assembled near infrared dataset has been implemented into a revised version of the Bologna Catalogue of M31 globulars, with updated optical (UBVRI) photometry taken, when possible, from the most recent sources of CCD photometry available in the literature and transformed to a common photometric system. The final Revised Bologna Catalogue (available in electronic form) is the most comprehensive list presently available of confirmed and candidate M31 globular clusters, with a total of 1164 entries. In particular, it includes 337 confirmed GCs, 688 GC candidates, 10 objects with controversial classification, 70 confirmed galaxies, 55 confirmed stars, and 4 HII regions lying within ~3 deg. from the center of the M31 galaxy. Using the newly assembled database we show that the V-K color provides a powerful tool to discriminate between M31 clusters and background galaxies, and we identify a sample of 83 globular cluster candidates, which is not likely to be contaminated by misclassified galaxies.Comment: 9 pages,5 figures,accepted for publication in Astronomy & Astrophysics ASCII (commented) version of the tables 2,3,4 are available at http://www.bo.astro.it/M3

Sawtooth period changes with mode conversion current drive on Alcator C-Mod

DEFC0299ER54512. Reproduction,  translation,  publication,  use and disposal,  in whole or in part,  by or for the United States government is permitted. Submitted for publication to Plasma Physics and Controlled Fusion. Sawtooth period changes with mode conversion current drive on Alcator C-Mo