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On 2014 December 9.61, the All-sky Automated Survey for SuperNovae (ASAS-SN or "Assassin") discovered ASASSN-141p just similar to 2 days after first light using a global array of 14 cm diameter telescopes. ASASSN-141p went on to become a bright supernova (V = 11.94 mag), second only to SN 2014J for the year. We present prediscovery photometry (with a detection less than a day after first light) and ultraviolet through near-infrared photometric and spectroscopic data covering the rise and fall of ASASSN-141p for more than 100 days. We find that ASASSN-141p had a broad light curve (Delta m(15) (B) = 0.80 +/- 0.05), a B-band maximum at 2457015.82 +/- 0.03, a rise time of 16.941(-0.10)(+0.11) days, and moderate host-galaxy extinction (E (B - V)host = 0.33 +/- 0.06). Using ASASSN-141p, we derive a distance modulus for NGC 4666 of mu = 30.8 +/- 0.2, corresponding to a distance of 14.7 +/- 1.5 Mpc. However, adding ASASSN-141p to the calibrating sample of Type Ia supernovae still requires an independent distance to the host galaxy. Finally, using our early-time photometric and spectroscopic observations, we rule out red giant secondaries and, assuming a favorable viewing angle and explosion time, any nondegenerate companion larger than 0.34 RG(circle dot).

We cross-match the two currently largest all-sky photometric catalogs, mid-infrared WISE and SuperCOSMOS scans of UKST/POSS-II photographic plates, to obtain a new galaxy sample that covers 3pi steradians. In order to characterize and purify the extragalactic dataset, we use external GAMA and SDSS spectroscopic information to define quasar and star loci in multicolor space, aiding the removal of contamination from our extended-source catalog. After appropriate data cleaning we obtain a deep wide-angle galaxy sample that is approximately 95% pure and 90% complete at high Galactic latitudes. The catalog contains close to 20 million galaxies over almost 70% of the sky, outside the Zone of Avoidance and other confused regions, with a mean surface density of over 650 sources per square degree. Using multiwavelength information from two optical and two mid-IR photometric bands, we derive photometric redshifts for all the galaxies in the catalog, using the ANNz framework trained on the final GAMA-II spectroscopic data. Our sample has a median redshift of z_{med} = 0.2 but with a broad dN/dz reaching up to z>0.4. The photometric redshifts have a mean bias of |delta_z|~10^{-3}, normalized scatter of sigma_z = 0.033 and less than 3% outliers beyond 3sigma_z. Comparison with external datasets shows no significant variation of photo-z quality with sky position. Together with the overall statistics, we also provide a more detailed analysis of photometric redshift accuracy as a function of magnitudes and colors. The final catalog is appropriate for `all-sky' 3D cosmology to unprecedented depths, in particular through cross-correlations with other large-area surveys. It should also be useful for source pre-selection and identification in forthcoming surveys such as TAIPAN or WALLABY., Data available from http://ssa.roe.ac.uk/WISExSCOS

The MAGIC (Major Atmospheric Gamma-ray Imaging Cherenkov) telescopes observed the BL Lac object H1722+119 (redshift unknown) for six consecutive nights between 2013 May 17 and 22, for a total of 12.5 h. The observations were triggered by high activity in the optical band measured by the KVA (Kungliga Vetenskapsakademien) telescope. The source was for the first time detected in the very high energy (VHE, $E > 100$ GeV) $\gamma$-ray band with a statistical significance of 5.9 $\sigma$. The integral flux above 150 GeV is estimated to be $(2.0\pm 0.5)$ per cent of the Crab Nebula flux. We used contemporaneous high energy (HE, 100 MeV $ < E < 100$ GeV) $\gamma$-ray observations from Fermi-LAT (Large Area Telescope) to estimate the redshift of the source. Within the framework of the current extragalactic background light models, we estimate the redshift to be $z = 0.34 \pm 0.15$. Additionally, we used contemporaneous X-ray to radio data collected by the instruments on board the Swift satellite, the KVA, and the OVRO (Owens Valley Radio Observatory) telescope to study multifrequency characteristics of the source. We found no significant temporal variability of the flux in the HE and VHE bands. The flux in the optical and radio wavebands, on the other hand, did vary with different patterns. The spectral energy distribution (SED) of H1722+119 shows surprising behaviour in the $\sim 3\times10^{14} - 10^{18}$ Hz frequency range. It can be modelled using an inhomogeneous helical jet synchrotron self-Compton model., Comment: 12 pages, 5 figures, 2 tables

We describe the algorithm used to select the Luminous Red Galaxy (LRG) sample for the extended Baryon Oscillation Spectroscopic Survey (eBOSS) of the Sloan Digital Sky Survey IV (SDSS-IV) using photometric data from both the SDSS and the Wide-Field Infrared Survey Explorer (WISE). LRG targets are required to meet a set of color selection criteria and have z-band and i-band MODEL magnitudes z < 19.95 and 19.9 < i < 21.8, respectively. Our algorithm selects roughly 50 LRG targets per square degree, the great majority of which lie in the redshift range 0.6 < z < 1.0 (median redshift 0.71). We demonstrate that our methods are highly effective at eliminating stellar contamination and lower-redshift galaxies. We perform a number of tests using spectroscopic data from SDSS-III/BOSS to determine the redshift reliability of our target selection and its ability to meet the science requirements of eBOSS. The SDSS spectra are of high enough signal-to-noise ratio that at least 89% of the target sample yields secure redshift measurements. We also present tests of the uniformity and homogeneity of the sample, demonstrating that it should be clean enough for studies of the large-scale structure of the universe at higher redshifts than SDSS-III/BOSS LRGs reached., Submitted in ApJS, 15 pages, 10 figures

We present the first public release of photometric redshifts, galaxy rest-frame properties and associated magnification values in the cluster and parallel pointings of the first two Frontier Fields, Abell-2744 and MACS-J0416. We exploit a multi-wavelength catalogue ranging from HST to ground-based K and Spitzer IRAC which is specifically designed to enable detection and measurement of accurate fluxes in crowded cluster regions. The multi-band information is used to derive photometric redshifts and physical properties of sources detected either in the H-band image alone or from a stack of four WFC3 bands. To minimize systematics median photometric redshifts are assembled from six different approaches to photo-z estimates. Their reliability is assessed through a comparison with available spectroscopic samples. State of the art lensing models are used to derive magnification values on an object-by-object basis by taking into account sources positions and redshifts. We show that photometric redshifts reach a remarkable ~3-5% accuracy. After accounting for magnification the H band number counts are found in agreement at bright magnitudes with number counts from the CANDELS fields, while extending the presently available samples to galaxies intrinsically as faint as H160~32-33 thanks to strong gravitational lensing. The Frontier Fields allow to probe the galaxy stellar mass distribution at 0.5-1.5 dex lower masses, depending on magnification, with respect to extragalactic wide fields, including sources at Mstar~ 10^7-10^8 Msun at z>5. Similarly, they allow the detection of objects with intrinsic SFRs>1dex lower than in the CANDELS fields reaching 0.1-1 Msun/yr at z~6-10. [abridged], 10 pages, 9 figures, accepted for publication on A&A. CDS images and catalogues interface at http://astrodeep.u-strasbg.fr/ff/ . Full catalogues available for download from the ASTRODEEP website at http://www.astrodeep.eu/frontier-fields/

We report the discovery of the largest giant radio galaxy, J1420-0545: a FR type II radio source with an angular size of 17.4' identified with an optical galaxy at z=0.3067. Thus, the projected linear size of the radio structure is 4.69 Mpc (if we assume that H_{0}=71 km\s\Mpc, Omega_{m}=0.27, and Omega_{\Lambda}=0.73). This makes it larger than 3C236, which is the largest double radio source known to date. New radio observations with the 100 m Effelsberg telescope and the Giant Metrewave Radio Telescope, as well as optical identification with a host galaxy and its optical spectroscopy with the William Herschel Telescope are reported. The spectrum of J1420-0545 is typical of elliptical galaxies in which continuum emission with the characteristic 4000A discontinuity and the H and K absorption lines are dominated by evolved stars. The dynamical age of the source, its jets' power, the energy density, and the equipartition magnetic field are calculated and compared with the corresponding parameters of other giant and normal-sized radio galaxies from a comparison sample. The source is characterized by the exceptionally low density of the surrounding IGM and an unexpectedly high expansion speed of the source along the jet axis. All of these may suggest a large inhomogeneity of the IGM., Comment: 20 pages, 5 figures, 3 tables

arXiv:1601.03668v1, We study the clustering of galaxies as a function of spectral type and redshift in the range 0.35, This work was mainly supported by the Spanish Ministry for Economy and Competitiveness and FEDER funds through grants AYA2010-22111-C03-02 and AYA2013-48623-C2-2, and by the Generalitat Valenciana through project PrometeoII 2014/060. We also acknowledge support from the Spanish Ministry for Economy and Competitiveness and FEDER funds through grants AYA2012-39620, AYA2013-40611-P, AYA2013-42227-P, AYA2013-43188-P, AYA2013-48623-C2-1, ESP2013-48274, AYA2014-58861-C3-1, Junta de Andalucia grants TIC114, JA2828, P10-FQM-6444, and Generalitat de Catalunya project SGR-1398. Begona Ascaso acknowledge funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 656354.

We explore the massive bluer star-forming population of the Sloan Digital Sky Survey (SDSS) III/BOSS CMASS DR11 galaxies at z > 0.55 to quantify their differences, in terms of redshiftspace distortions and large-scale bias, with respect to the luminous red galaxy sample. We perform a qualitative analysis to understand the significance of these differences and whether we can model and reproduce them in mock catalogues. Specifically, we measure galaxy clustering in CMASS on small and intermediate scales (0.1 ≲ r ≲ 50 h Mpc) by computing the two-point correlation function - both projected and redshift-space - of these galaxies, and a new statistic, Σ(π), able to separate the coherent and dispersed redshift-space distortion contributions and the large-scale bias. We interpret our clustering measurements by adopting a Halo Occupation Distribution (HOD) scheme that maps them on to high-resolution N-body cosmological simulations to produce suitable mock galaxy catalogues. The traditional HOD prescription can be applied to the red and the blue samples, independently, but this approach is unphysical since it allows the same mock galaxies to be either red or blue. To overcome this ambiguity, we modify the standard formulation and infer the red and the blue models by splitting the full mock catalogue into two complementary and non-overlapping submocks. This separation is performed by constraining the HOD with the observed CMASS red and blue galaxy fractions and produces reliable and accurate models. © 2016 The Authors., GF is supported by the Ministerio de Educacion y Ciencia of the Spanish Government through FPI grant AYA2010-2131-C02-01 and wishes to thank the Smithsonian Center for Astrophysics and the Harvard University, Astronomy Department, for the hospitality during the creation of this work. GF acknowledges support from the Spanish Government through EEBB-I-13-07167 and EEBB-I-12-05220 grants. GF, FP, and CC acknowledge support from the Spanish MICINNs Consolider-Ingenio 2010 Programme under grant MultiDark CSD2009-00064, MINECO Centro de Excelencia Severo Ochoa Programme under grant SEV-2012-0249, and MINECO grant AYA2014-60641-C2-1-P. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation and the U.S. Department of Energy.

Current and future large redshift surveys, as the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey (SDSS-IV/eBOSS) or the Dark Energy Spectroscopic Instrument (DESI), will use emission-line galaxies (ELGs) to probe cosmological models by mapping the large-scale structure of the Universe in the redshift range 0.6 < z < 1.7. With current data, we explore the halo-galaxy connection by measuring three clustering properties of g-selected ELGs as matter tracers in the redshift range 0.6 < z < 1: (i) the redshift-space two-point correlation function using spectroscopic redshifts from the BOSS ELG sample and VIPERS; (ii) the angular two-point correlation function on the footprint of the CFHT-LS; (iii) the galaxy-galaxy lensing signal around the ELGs using the CFHTLenS. We interpret these observations by mapping them on to the latest high-resolution MultiDark Planck N-body simulation, using a novel (Sub)Halo-Abundance Matching technique that accounts for the ELG incompleteness. ELGs at z ~ 0.8 live in haloes of (1 ± 0.5) × 10 hM⊙ and 22.5 ± 2.5 per cent of them are satellites belonging to a larger halo. The halo occupation distribution of ELGs indicates that we are sampling the galaxies in which stars form in the most efficient way, according to their stellar-to-halo mass ratio. © 2016 The Authors., GF is supported by the Ministerio de Educacion y Ciencia of the Spanish Government through FPI grant AYA2010-2131-C02-01. JC acknowledges financial support from MINECO (Spain) under project number AYA2012-31101. GY acknowledges financial support from MINECO (Spain) under project number AYA2012-31101 and grant FPA2012-34694. EJ acknowledges the support of CNRS, and the Labex OCEVU. SEN acknowledges support by the Deutsche Forschungsgemeinschaft under the grant NU 332/21. GF, FP, SART, AK, SN and CC acknowledge financial support from the Spanish MICINN Consolider-Ingenio 2010 Programme under grant MultiDark CSD2009-00064, MINECO Centro de Excelencia Severo Ochoa Programme under grant SEV-2012-0249, and MINECO grant AYA2014-60641-C2-1-P. GF, JC and FP wish to thank the Lawrence Berkeley National Laboratory for the hospitality during the creation of this work. FP acknowledges the spanish MEC 'Salvador de Madariaga' program, Ref. PRX14/00444.

International audience; We explore the accuracy of the clustering-based redshift estimation proposed by Menard et al. when applied to VIMOS Public Extragalactic Redshift Survey (VIPERS) and Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) real data. This method enables us to reconstruct redshift distributions from measurement of the angular clustering of objects using a set of secure spectroscopic redshifts. We use state-of-the-art spectroscopic measurements with i(AB) \textless 22.5 from the VIPERS as reference population to infer the redshift distribution of galaxies from the CFHTLS T0007 release. VIPERS provides a nearly representative sample to a flux limit of iAB \textless 22.5 at a redshift of \textgreater 0.5 which allows us to test the accuracy of the clustering-based redshift distributions. We show that this method enables us to reproduce the true mean colour-redshift relation when both populations have the same magnitude limit. We also show that this technique allows the inference of redshift distributions for a population fainter than the reference and we give an estimate of the colour-redshift mapping in this case. This last point is of great interest for future large-redshift surveys which require a complete faint spectroscopic sample.

The determination of galaxy redshifts in James Webb Space Telescope (JWST)'s blank-field surveys will mostly rely on photometric estimates, based on the data provided by JWST's Near-Infrared Camera (NIRCam) at 0.6-5.0 {\mu}m and Mid Infrared Instrument (MIRI) at {\lambda}>5.0 {\mu}m. In this work we analyse the impact of choosing different combinations of NIRCam and MIRI broad-band filters (F070W to F770W), as well as having ancillary data at {\lambda}=10, but the zphot quality significantly degrades at S/N, Comment: 29 pages, 27 figures, 12 tables. Accepted for publication at the ApJS

The Astrophysical Journal 221.2 (2015): 27 reproduced by permission of the AAS, As part of the Sloan Digital Sky Survey (SDSS) IV the extended Baryon Oscillation Spectroscopic Survey (eBOSS) will improve measurements of the cosmological distance scale by applying the Baryon Acoustic Oscillation (BAO) method to quasar samples. eBOSS will adopt two approaches to target quasars over 7500 deg2. First, a "CORE" quasar sample will combine the optical selection in ugriz using a likelihood-based routine called XDQSOz, with a mid-IR-optical color cut. eBOSS CORE selection (to g < 22 or r < 22) should return ∼70 deg-2 quasars at redshifts 0.9 < z < 2.2 and ∼7 deg-2z > 2.1 quasars. Second, a selection based on variability in multi-epoch imaging from the Palomar Transient Factory should recover an additional ∼3-4 deg-2z > 2.1 quasars to g < 22.5. A linear model of how imaging systematics affect target density recovers the angular distribution of eBOSS CORE quasars over 96.7% (76.7%) of the SDSS north (south) Galactic Cap area. The eBOSS CORE quasar sample should thus be sufficiently dense and homogeneous over 0.9 < z < 2.2 to yield the first few-percent-level BAO constraint near eBOSS quasars at z > 2.1 will be used to improve BAO measurements in the Lyα Forest. Beyond its key cosmological goals, eBOSS should be the next-generation quasar survey, comprising >500,000 new quasars and >500,000 uniformly selected spectroscopically confirmed 0.9 < z < 2.2 quasars. At the conclusion of eBOSS, the SDSS will have provided unique spectra for more than 800,000 quasars, We are grateful for insightful discussions about quasar selection statistics with Joe Hennawi, David Hogg, and Gordon Richards. A.D.M. acknowledges a generous research fellowship from the Alexander von Humboldt Foundation at the MaxPlanck-Institut für Astronomie and was supported in part by NASA-ADAP awards NNX12AI49G and NNX12AE38G and by NSF awards 1211112 and 1515404. J.P.K. acknowledges support from the ERC advanced grant LIDA. This paper includes targets derived from the images of the Wide-Field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the JetPropulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This paper represents an effort by both the SDSS-III and SDSS-IV collaborations. Funding for SDSS-III was provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS-IV acknowledges support and resources from the Center for HighPerformance Computing at the University of Utah. The SDSS web site is www.sdss.org.

We present a Hubble diagram of SNe II using corrected magnitudes derived only from photometry, with no input of spectral information. We use a data set from the Carnegie Supernovae Project I for which optical and near-infrared light curves were obtained. The apparent magnitude is corrected by two observables, one corresponding to the slope of the plateau in the V band and the second a color term. We obtain a dispersion of 0.44 mag using a combination of the (V - i) color and the r band and we are able to reduce the dispersion to 0.39 mag using our golden sample. A comparison of our photometric color method (PCM) with the standardized candle method (SCM) is also performed. The dispersion obtained for the SCM (which uses both photometric and spectroscopic information) is 0.29 mag, which compares with 0.43 mag from the PCM for the same SN sample. The construction of a photometric Hubble diagram is of high importance in the coming era of large photometric wide-field surveys, which will increase the detection rate of supernovae by orders of magnitude. Such numbers will prohibit spectroscopic follow up in the vast majority of cases, and hence methods must be deployed which can proceed using solely photometric data., La lista completa de autores que integran el documento puede consultarse en el archivo., Facultad de Ciencias Astronómicas y Geofísicas, Instituto de Astrofísica de La Plata

The Galaxy And Mass Assembly (GAMA) survey is one of the largest contemporary spectroscopic surveys of low-redshift galaxies. Covering an area of ~286 deg^2 (split among five survey regions) down to a limiting magnitude of r < 19.8 mag, we have collected spectra and reliable redshifts for 238,000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope. In addition, we have assembled imaging data from a number of independent surveys in order to generate photometry spanning the wavelength range 1 nm - 1 m. Here we report on the recently completed spectroscopic survey and present a series of diagnostics to assess its final state and the quality of the redshift data. We also describe a number of survey aspects and procedures, or updates thereof, including changes to the input catalogue, redshifting and re-redshifting, and the derivation of ultraviolet, optical and near-infrared photometry. Finally, we present the second public release of GAMA data. In this release we provide input catalogue and targeting information, spectra, redshifts, ultraviolet, optical and near-infrared photometry, single-component S��rsic fits, stellar masses, H$��$-derived star formation rates, environment information, and group properties for all galaxies with r < 19.0 mag in two of our survey regions, and for all galaxies with r < 19.4 mag in a third region (72,225 objects in total). The database serving these data is available at http://www.gama-survey.org/., Accepted for publication in MMRAS, 40 pages, 33 figures

We present the catalogue of blended galaxy spectra from the Galaxy And Mass Assembly (GAMA) survey. These are cases where light from two galaxies are significantly detected in a single GAMA fibre. Galaxy pairs identified from their blended spectrum fall into two principal classes: they are either strong lenses, a passive galaxy lensing an emission-line galaxy; or occulting galaxies, serendipitous overlaps of two galaxies, of any type. Blended spectra can thus be used to reliably identify strong lenses for follow-up observations (high resolution imaging) and occulting pairs, especially those that are a late-type partly obscuring an early-type galaxy which are of interest for the study of dust content of spiral and irregular galaxies. The GAMA survey setup and its autoz automated redshift determination were used to identify candidate blended galaxy spectra from the cross-correlation peaks. We identify 280 blended spectra with a minimum velocity separation of 600 km/s, of which 104 are lens pair candidates, 71 emission-line-passive pairs, 78 are pairs of emission-line galaxies and and 27 are pairs of galaxies with passive spectra. We have visually inspected the candidates in the Sloan Digital Sky Survey (SDSS) and Kilo Degree Survey (KiDS) images. Many blended objects are ellipticals with blue fuzz (Ef in our classification). These latter "Ef" classifications are candidates for possible strong lenses, massive ellipticals with an emission-line galaxy in one or more lensed images. The GAMA lens and occulting galaxy candidate samples are similar in size to those identified in the entire SDSS. This blended spectrum sample stands as a testament of the power of this highly complete, second-largest spectroscopic survey in existence and offers the possibility to expand e.g., strong gravitational lens surveys., Comment: 12 pages, 10 figures, 3 tables. Table 3 full length version is in the appendix. Accepted for publication by MNRAS, typo fixed so Figure 2 is included properly

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved, We present a simple method of generating approximate synthetic halo catalogues: HALOGEN. This method uses a combination of second-order Lagrangian Perturbation Theory (2LPT) in order to generate the large-scale matter distribution, analytical mass functions to generate halo masses, and a single-parameter stochastic model for halo bias to position haloes. HALOGEN represents a simplification of similar recently published methods. Our method is constrained to recover the two-point function at intermediate (10 h-1 Mpc, SA and JGB acknowledge financial support from the Spanish MINECO under grant FPA39684-C03-02 and Consolider-Ingenio “Physics of the Accelerating Universe (PAU)” (CSD2007-00060). They also acknowledge the support from the Spanish MINECO’s “Centro de Excelencia Severo Ochoa” Programme under Grant No. SEV-2012-0249. SA is also supported by a PhD FPI-fellowship from the Universidad Autónoma de Madrid. AK is supported by the Ministerio de Economía y Competitividad (MINECO) in Spain through grant AYA2012-31101 as well as the Consolider-Ingenio 2010 Programme of the Spanish Ministerio de Ciencia e Innovación (MICINN) under grant MultiDark CSD2009-00064. He also acknowledges support from the Australian Research Council (ARC) grants DP130100117 and DP140100198

We use ultradeep SCUBA-2 850um observations (~0.37 mJy rms) of the 2 Ms Chandra Deep Field-North (CDF-N) and 4 Ms Chandra Deep Field-South (CDF-S) X-ray fields to examine the amount of dusty star formation taking place in the host galaxies of high-redshift X-ray AGNs. Supplementing with COSMOS, we measure the submillimeter fluxes of the 4-8 keV sources at z>1, finding little flux at the highest X-ray luminosities but significant flux at intermediate luminosities. We determine gray body and MIR luminosities by fitting spectral energy distributions to each X-ray source and to each radio source in an ultradeep Karl G. Jansky Very Large Array (VLA) 1.4 GHz (11.5uJy at 5-sigma) image of the CDF-N. We confirm the FIR-radio and MIR-radio correlations to z=4 using the non-X-ray detected radio sources. Both correlations are also obeyed by the X-ray less luminous AGNs but not by the X-ray quasars. We interpret the low FIR luminosities relative to the MIR for the X-ray quasars as being due to a lack of star formation, while the MIR stays high due to the AGN contribution. We find that the FIR luminosity distributions are highly skewed and the means are dominated by a small number of high-luminosity galaxies. Thus, stacking or averaging analyses will overestimate the level of star formation taking place in the bulk of the X-ray sample. We conclude that most of the host galaxies of X-ray quasars are not strong star formers, perhaps because their star formation is suppressed by AGN feedback., 16 pages, updated to The Astrophysical Journal accepted version

Weak lensing is emerging as a powerful observational tool to constrain cosmological models, but is at present limited by an incomplete understanding of many sources of systematic error. Many of these errors are multiplicative and depend on the population of background galaxies. We show how the commonly cited geometric test, which is rather insensitive to cosmology, can be used as a ratio test of systematics in the lensing signal at the 1 per cent level. We apply this test to the galaxy-galaxy lensing analysis of the Sloan Digital Sky Survey (SDSS), which at present is the sample with the highest weak lensing signal to noise and has the additional advantage of spectroscopic redshifts for lenses. This allows one to perform meaningful geometric tests of systematics for different subsamples of galaxies at different mean redshifts, such as brighter galaxies, fainter galaxies and high-redshift luminous red galaxies, both with and without photometric redshift estimates. We use overlapping objects between SDSS and the DEEP2 and 2SLAQ spectroscopic surveys to establish accurate calibration of photometric redshifts and to determine the redshift distributions for SDSS. We use these redshift results to compute the projected surface density contrast DeltaSigma around 259 609 spectroscopic galaxies in the SDSS; by measuring DeltaSigma with different source samples we establish consistency of the results at the 10 per cent level (1-sigma). We also use the ratio test to constrain shear calibration biases and other systematics in the SDSS survey data to determine the overall galaxy-galaxy weak lensing signal calibration uncertainty. We find no evidence of any inconsistency among many subsamples of the data., 39 pages, 19 figures

© 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. We present the measurements and modelling of the projected and redshift-space clustering of CMASS galaxies in the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey Data Release 11. For a volume-limited luminous red galaxy sample in the redshift range of 0.48 < z < 0.55, we perform halo occupation distribution modelling of the small- and intermediate-scale (0.1-60 h-1Mpc) projected and redshift-space two-point correlation functions, with an accurate model built on high-resolution N-body simulations. To interpret the measured redshift-space distortions, the distribution of galaxy velocities must differ from that of the dark matter inside haloes of ~1013-1014h-1M⊙, i.e. the data require the existence of galaxy velocity bias. Most notably, central galaxies on average are not at rest with respect to the core of their host haloes, but rather move around it with a 1D velocity dispersion of 0.22-0.04+0.03times that of the dark matter, implying a spatial offset from the centre at the level of ≲1 per cent of the halo virial radius. The luminous satellite galaxies move more slowly than the dark matter, with velocities 0.86-0.03+0.08times those of the dark matter, which suggests that the velocity and spatial distributions of these satellites cannot both be unbiased. The constraints mainly arise from the Fingers-of-God effect at non-linear scales and the smoothing to the Kaiser effect in the translinear regime; the robustness of the results is demonstrated by a variety of tests. We discuss the implications of the existence of galaxy velocity bias for investigations of galaxy formation and cosmology.

Based on observations collected at the German-Spanish Astronomical Center, Calar Alto, jointly operated by the Max-Planck-Institut für Astronomie (MPIA) at Heidelberg and the Instituto de Astrofísica de Andalucía (CSIC).-- et al., [Context]: Most observational results on the high redshift restframe UV-bright galaxies are based on samples pinpointed using the so-called dropout technique or Ly-α selection. However, the availability of multifilter data now allows the dropout selections to be replaced by direct methods based on photometric redshifts. In this paper we present the methodology to select and study the population of high redshift galaxies in the ALHAMBRA survey data. [Aims]: Our aim is to develop a less biased methodology than the traditional dropout technique to study the high redshift galaxies in ALHAMBRA and other multifilter data. Thanks to the wide area ALHAMBRA covers, we especially aim at contributing to the study of the brightest, least frequent, high redshift galaxies. [Methods]: The methodology is based on redshift probability distribution functions (zPDFs). It is shown how a clean galaxy sample can be obtained by selecting the galaxies with high integrated probability of being within a given redshift interval. However, reaching both a complete and clean sample with this method is challenging. Hence, a method to derive statistical properties by summing the zPDFs of all the galaxies in the redshift bin of interest is introduced. [Results]: Using this methodology we derive the galaxy rest frame UV number counts in five redshift bins centred at z = 2.5,3.0,3.5,4.0, and 4.5, being complete up to the limiting magnitude at mUV(AB) = 24, where mUV refers to the first ALHAMBRA filter redwards of the Ly-α line. With the wide field ALHAMBRA data we especially contribute to the study of the brightest ends of these counts, accurately sampling the surface densities down to mUV(AB) = 21-22. [Conclusions]: We show that using the zPDFs it is easy to select a very clean sample of high redshift galaxies. We also show that it is better to do statistical analysis of the properties of galaxies using a probabilistic approach, which takes into account both the incompleteness and contamination issues in a natural way., K. Viironen acknowledges the Juan de la Cierva fellowship of the Spanish government. We acknowledge funding from the FITE (Fondos de Inversiones de Teruel) and support from the Spanish Ministry for Economy and Competitiveness and FEDER funds through grants AYA2012-30789, AYA2006-14056, AYA 2003-00128, AYA 2006-01325, AYA 2007-62190, AYA2010-15169, AYA2010-22111-C03-02 and AYA2013-48623-C2-2. We also acknowledge Junta de Andalucía through the grant TIC 114 and Generalitat Valenciana projects Prometeo 2009/064 and PROMETEOII/2014/060, and the financial support from the Aragón Government through the Research Group E103. I. Oteo acknowledges support from the European Research Council (ERC) in the form of Advanced Grant, cosmicism. A. J. Cenarro acknowledges the Ramón y Cajal fellowship of the Spanish government. M. Povic acknowledges financial support from JAE-Doc program of the Spanish National Research Council (CSIC), cofunded by the European Social Fund.

Context. The present literature does not give a satisfactory answer to the question about the nature of the "Antlia galaxy cluster". Aims. The radial velocities of galaxies found in the region around the giant ellipticals NGC 3258/3268 range from about 1000 km s-1 to 4000 km s-1. We characterise this region and its possible kinematical and population substructure. Methods. We have obtained VLT-VIMOS multi-object spectra of the galaxy population in the inner part of the Antlia cluster and measure radial velocities for 45 potential members. We supplement our galaxy sample with literature data, ending up with 105 galaxy velocities. Results. We find a large radial velocity dispersion for the entire sample as reported in previous papers. However, we find three groups at about 1900 km s-1, 2800 km s-1, and 3700 km s-1, which we interpret as differences in the recession velocities rather than peculiar velocities. Conclusions. The high radial velocity dispersion of galaxies in the Antlia region reflects a considerable extension along the line of sight., Facultad de Ciencias Astronómicas y Geofísicas

We present extensive optical ($UBVRI$, $g'r'i'z'$, and open CCD) and near-infrared ($ZYJH$) photometry for the very nearby Type IIP SN ~2013ej extending from +1 to +461 days after shock breakout, estimated to be MJD $56496.9\pm0.3$. Substantial time series ultraviolet and optical spectroscopy obtained from +8 to +135 days are also presented. Considering well-observed SNe IIP from the literature, we derive $UBVRIJHK$ bolometric calibrations from $UBVRI$ and unfiltered measurements that potentially reach 2\% precision with a $B-V$ color-dependent correction. We observe moderately strong Si II $\lambda6355$ as early as +8 days. The photospheric velocity ($v_{\rm ph}$) is determined by modeling the spectra in the vicinity of Fe II $\lambda5169$ whenever observed, and interpolating at photometric epochs based on a semianalytic method. This gives $v_{\rm ph} = 4500\pm500$ km s$^{-1}$ at +50 days. We also observe spectral homogeneity of ultraviolet spectra at +10--12 days for SNe IIP, while variations are evident a week after explosion. Using the expanding photosphere method, from combined analysis of SN 2013ej and SN 2002ap, we estimate the distance to the host galaxy to be $9.0_{-0.6}^{+0.4}$ Mpc, consistent with distance estimates from other methods. Photometric and spectroscopic analysis during the plateau phase, which we estimated to be $94\pm7$ days long, yields an explosion energy of $0.9\pm0.3\times10^{51}$ ergs, a final pre-explosion progenitor mass of $15.2\pm4.2$~M$_\odot$ and a radius of $250\pm70$~R$_\odot$. We observe a broken exponential profile beyond +120 days, with a break point at +$183\pm16$ days. Measurements beyond this break time yield a $^{56}$Ni mass of $0.013\pm0.001$~M$_\odot$., Comment: 29 pages, 23 figures, 15 tables, Published in The Astrophisical Journal

The VISTA survey of the Magellanic Clouds System (VMC) is collecting deep $K_\mathrm{s}$--band time--series photometry of the pulsating variable stars hosted in the system formed by the two Magellanic Clouds and the Bridge connecting them. In this paper we have analysed a sample of 130 Large Magellanic Cloud (LMC) Type II Cepheids (T2CEPs) found in tiles with complete or near complete VMC observations for which identification and optical magnitudes were obtained from the OGLE III survey. We present $J$ and $K_\mathrm{s}$ light curves for all 130 pulsators, including 41 BL Her, 62 W Vir (12 pW Vir) and 27 RV Tau variables. We complement our near-infrared photometry with the $V$ magnitudes from the OGLE III survey, allowing us to build a variety of Period-Luminosity ($PL$), Period-Luminosity-Colour ($PLC$) and Period-Wesenheit ($PW$) relationships, including any combination of the $V, J, K_\mathrm{s}$ filters and valid for BL Her and W Vir classes. These relationships were calibrated in terms of the LMC distance modulus, while an independent absolute calibration of the $PL(K_\mathrm{s})$ and the $PW(K_\mathrm{s},V)$ was derived on the basis of distances obtained from $Hubble Space Telescope$ parallaxes and Baade-Wesselink technique. When applied to the LMC and to the Galactic Globular Clusters hosting T2CEPs, these relations seem to show that: 1) the two population II standard candles RR Lyrae and T2CEPs give results in excellent agreement with each other; 2) there is a discrepancy of $\sim$0.1 mag between population II standard candles and Classical Cepheids when the distances are gauged in a similar way for all the quoted pulsators. However, given the uncertainties, this discrepancy is within the formal 1$\sigma$ uncertainties., Comment: 18 pages + Appendix (14 pages). Accepted for publication on MNRAS

The astrophysical journal 802(1), 65 - (2015). doi:10.1088/0004-637X/802/1/65, Very high energy (VHE, E > 100 GeV) $\gamma-ray$ flaring activity of the high-frequency peaked BL Lac object PG 1553+113 has been detected by the H.E.S.S. telescopes. The flux of the source increased by a factor of 3 during the nights of 2012 April 26 and 27 with respect to the archival measurements with a hint of intra-night variability. No counterpart of this event has been detected in the Fermi-Large Area Telescope data. This pattern is consistent with VHE $\gamma-ray$ flaring being caused by the injection of ultrarelativistic particles, emitting $\gamma-rays$ at the highest energies. The dataset offers a unique opportunity to constrain the redshift of this source at z = 0.49 $\pm$ 0.04 using a novel method based on Bayesian statistics. The indication of intra-night variability is used to introduce a novel method to probe for a possible Lorentz invariance violation (LIV), and to set limits on the energy scale at which Quantum Gravity (QG) effects causing LIV may arise. For the subluminal case, the derived limits are $E_{QG,1}$ > 4.10 × $10^{17}$ GeV and $E_{QG,2}$ > 2.10 × $10^{10}$ GeV for linear and quadratic LIV effects, respectively., Published by Univ.11032, Chicago, Ill. [u.a.]

X-ray and radio observations of CIZA J2242.8+5301 suggest that it is a major cluster merger. Despite being well studied in the X-ray, and radio, little has been presented on the cluster structure and dynamics inferred from its galaxy population. We carried out a deep (i, 17 pages, 14 figures, submitted to ApJ

We describe techniques concerning wavelength calibration and sky subtraction to maximize the scientific utility of data from tunable filter instruments. While we specifically address data from the Optical System for Imaging and low Resolution Integrated Spectroscopy instrument (OSIRIS) on the 10.4-m Gran Telescopio Canarias telescope, our discussion is generalizable to data from other tunable filter instruments. A key aspect of our methodology is a coordinate transformation to polar coordinates, which simplifies matters when the tunable filter data are circularly symmetric around the optical centre. First, we present a method for rectifying inaccuracies in the wavelength calibration using OH sky emission rings. Using this technique, we improve the absolute wavelength calibration from an accuracy of ∼5 to 1 Å, equivalent to ∼7 per cent of our instrumental resolution, for 95 per cent of our data. Then, we discuss a new way to estimate the background sky emission by median filtering in polar coordinates. This method suppresses contributions to the sky background from the outer envelopes of distant galaxies, maximizing the fluxes of sources measured in the corresponding sky-subtracted images. We demonstrate for data tuned to a central wavelength of 7615 Å that galaxy fluxes in the new sky-subtracted image are ∼37 per cent higher, versus a sky-subtracted image from existing methods for OSIRIS tunable filter data.

The galaxy stellar mass function (GSMF) at high-z provides key information on star-formation history and mass assembly in the young Universe. We aimed to use the unique combination of deep optical/NIR/MIR imaging provided by HST, Spitzer and the VLT in the CANDELS-UDS, GOODS-South, and HUDF fields to determine the GSMF over the redshift range 3.54. These results confirm the unique synergy of the CANDELS+HUDF, HUGS, and SEDS surveys for the discovery and study of moderate/low-mass galaxies at high redshifts., Comment: 26 pages, 23 figures. Accepted for publication on A&A

We present HI 21cm observations of 1194 galaxies out to a redshift of 10,000 km/s selected as inclined spirals (i>60deg) from the 2MASS Redshift Survey. These observations were carried out at the National Radio Astronomy Observatory Robert C. Byrd Green Bank Telescope (GBT). This observing program is part of the 2MASS Tully-Fisher (2MTF) survey. This project will combine HI widths from these GBT observations with those from further dedicated observing at the Parkes Telescope, from the ALFALFA survey at Arecibo, and S/N>10 and spectral resolution, v_res < 10km/s published widths from a variety of telescopes. We will use these HI widths along with 2MASS photometry to estimate Tully-Fisher distances to nearby spirals and investigate the peculiar velocity field of the local Universe. In this paper we report on detections of neutral hydrogen in emission in 727 galaxies, and measure good signal-to-noise and symmetric HI global profiles suitable for use in the Tully-Fisher relation in 484., 13 pages. MNRAS in press. Supplementary files containing full multipage versions of figures in Appendix A, the tables in Appendix B and other data can be found at http://icg.port.ac.uk/~mastersk/2MTF/

We investigate the luminosity and colour dependence of clustering of CMASS galaxies in the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey Tenth Data Release. The halo occupation distribution framework is adopted to model the projected two-point correlation function measurements on small and intermediate scales (from $0.02$ to $60\,h^{-1}{\rm {Mpc}}$) and to interpret the observed trends and infer the connection of galaxies to dark matter halos. We find that luminous red galaxies reside in massive halos of mass $M{\sim}10^{13}$--$10^{14}\,h^{-1}{\rm M_\odot}$ and more luminous galaxies are more clustered and hosted by more massive halos. The strong small-scale clustering requires a fraction of these galaxies to be satellites in massive halos, with the fraction at the level of 5--8 per cent and decreasing with luminosity. The characteristic mass of a halo hosting on average one satellite galaxy above a luminosity threshold is about a factor $8.7$ larger than that of a halo hosting a central galaxy above the same threshold. At a fixed luminosity, progressively redder galaxies are more strongly clustered on small scales, which can be explained by having a larger fraction of these galaxies in the form of satellites in massive halos. Our clustering measurements on scales below $0.4\,h^{-1}{\rm {Mpc}}$ allow us to study the small-scale spatial distribution of satellites inside halos. While the clustering of luminosity-threshold samples can be well described by a Navarro-Frenk-White (NFW) profile, that of the reddest galaxies prefers a steeper or more concentrated profile. Finally, we also use galaxy samples of constant number density at different redshifts to study the evolution of luminous galaxies, and find the clustering to be consistent with passive evolution in the redshift range of $0.5 \lesssim z \lesssim 0.6$., Comment: MNRAS Accepted. Minor revisions from the last version

We studied the chronology of galactic bulge and disc formation by analysing the relative contributions of these components to the B-band rest-frame luminosity density at different epochs. We present the first estimate of the evolution of the fraction of rest-frame B-band light in galactic bulges and discs since redshift z~0.8. We performed a bulge-to-disc decomposition of HST/ACS images of 3266 galaxies in the zCOSMOS-bright survey with spectroscopic redshifts in the range 0.7 < z < 0.9. We find that the fraction of B-band light in bulges and discs is $(26 \pm 4)%$ and $(74 \pm 4)%$, respectively. When compared with rest-frame B-band measurements of galaxies in the local Universe in the same mass range ($10^{9} M_{\odot}\lessapprox M \lessapprox 10^{11.5} M_{\odot}$), we find that the B-band light in discs decreases by ~30% from z~0.7-0.9 to z~0, while the light from the bulge increases by ~30% over the same period of time. We interpret this evolution as the consequence of star formation and mass assembly processes, as well as morphological transformation, which gradually shift stars formed at half the age of the Universe from star-forming late-type/irregular galaxies toearlier types and ultimately into spheroids., Letter to the Editor, 4 pages, 2 figures, accepted for publication in Astronomy and Astrophysics

(Abridged) Fossil systems are group- or cluster-sized objects whose luminosity is dominated by a very massive central galaxy. In the current cold dark matter scenario, these objects formed hierarchically at an early epoch of the Universe and then slowly evolved until present day. That is the reason why they are called {\it fossils}. We started an extensive observational program to characterize a sample of 34 fossil group candidates spanning a broad range of physical properties. Deep $r-$band images were taken for each candidate and optical spectroscopic observations were obtained for $\sim$ 1200 galaxies. This new dataset was completed with SDSS DR7 archival data to obtain robust cluster membership and global properties of each fossil group candidate. For each system, we recomputed the magnitude gaps between the two brightest galaxies ($\Delta m_{12}$) and the first and fourth ranked galaxies ($\Delta m_{14}$) within 0.5 $R_{{\rm 200}}$. We consider fossil systems those with $\Delta m_{12} \ge 2$ mag or $\Delta m_{14} \ge 2.5$ mag within the errors. We find that 15 candidates turned out to be fossil systems. Their observational properties agree with those of non-fossil systems. Both follow the same correlations, but fossils are always extreme cases. In particular, they host the brightest central galaxies and the fraction of total galaxy light enclosed in the central galaxy is larger in fossil than in non-fossil systems. Finally, we confirm the existence of genuine fossil clusters. Combining our results with others in the literature, we favor the merging scenario in which fossil systems formed due to mergers of $L^\ast$ galaxies. The large magnitude gap is a consequence of the extreme merger ratio within fossil systems and therefore it is an evolutionary effect. Moreover, we suggest that at least one candidate in our sample could represent a transitional fossil stage., Comment: 14 pages, 11 figures, accepted for publication in A&A

We present the first Public Data Release (PDR-1) of the VIMOS Public Extragalactic Survey (VIPERS). It comprises 57 204 spectroscopic measurements together with all additional information necessary for optimal scientific exploitation of the data, in particular the associated photometric measurements and quantification of the photometric and survey completeness. VIPERS is an ESO Large Programme designed to build a spectroscopic sample of ' 100 000 galaxies with iAB < 22.5 and 0.5 < z < 1.5 with high sampling rate (~45%). The survey spectroscopic targets are selected from the CFHTLS-Wide five-band catalogues in the W1 and W4 fields. The final survey will cover a total area of nearly 24 deg2, for a total comoving volume between z = 0.5 and 1.2 of ~4x10^7 h^(-3)Mpc^3 and a median galaxy redshift of z~0.8. The release presented in this paper includes data from virtually the entire W4 field and nearly half of the W1 area, thus representing 64% of the final dataset. We provide a detailed description of sample selection, observations and data reduction procedures; we summarise the global properties of the spectroscopic catalogue and explain the associated data products and their use, and provide all the details for accessing the data through the survey database (http://vipers.inaf.it) where all information can be queried interactively., Accepted for publication in A&A Added and/or replaced some figure, added section on DataBase interface, expaned Introduction

We present a novel method to estimate accurate redshifts of star-forming galaxies by measuring the flux ratio of the same emission line observed through two adjacent narrow-band filters. We apply this method to our NB912 and new NB921 data taken with Suprime-Cam on the Subaru Telescope of a galaxy cluster, XMMXCS J2215.9-1738, at z=1.46 and its surrounding structures. We obtain redshifts for 170 [OII] emission line galaxies at z~1.46, among which 41 galaxies are spectroscopically confirmed with MOIRCS and FMOS on the Subaru mainly, showing an accuracy of $\sigma$((z-z_spec})/(1+z_spec))=0.002. This allows us to reveal filamentary structures that penetrate towards the centre of the galaxy cluster and intersect with other structures, consistent with the picture of hierarchical cluster formation. We also find that the projected celestial distribution does not precisely trace the real distribution of galaxies, indicating the importance of the three dimensional view of structures to properly identify and quantify galaxy environments. We investigate the environmental dependence of galaxy properties with local density, confirming that the median colour of galaxies becomes redder in higher density region while the star-formation rate of star-forming galaxies does not depend strongly on local environment in this structure. This implies that the star-forming activity in galaxies is truncated on a relatively short time scale in the cluster centre., Comment: 14 pages, 9 figures, 1 table, accepted for publication in MNRAS

We use the James Clerk Maxwell Telescope's SCUBA-2 camera to image a 400 arcmin^2 area surrounding the GOODS-N field. The 850 micron rms noise ranges from a value of 0.49 mJy in the central region to 3.5 mJy at the outside edge. From these data, we construct an 850 micron source catalog to 2 mJy containing 49 sources detected above the 4-sigma level. We use an ultradeep (11.5 uJy at 5-sigma) 1.4 GHz image obtained with the Karl G. Jansky Very Large Array together with observations made with the Submillimeter Array to identify counterparts to the submillimeter galaxies. For most cases of multiple radio counterparts, we can identify the correct counterpart from new and existing Submillimeter Array data. We have spectroscopic redshifts for 62% of the radio sources in the 9 arcmin radius highest sensitivity region (556/894) and 67% of the radio sources in the GOODS-N region (367/543). We supplement these with a modest number of additional photometric redshifts in the GOODS-N region (30). We measure millimetric redshifts from the radio to submillimeter flux ratios for the unidentified submillimeter sample, assuming an Arp 220 spectral energy distribution. We find a radio flux dependent K-z relation for the radio sources, which we use to estimate redshifts for the remaining radio sources. We determine the star formation rates (SFRs) of the submillimeter sources based on their radio powers and their submillimeter and find that they agree well. The radio data are deep enough to detect star-forming galaxies with SFRs >2000 solar masses per year to z~6. We find galaxies with SFRs up to ~6,000 solar masses per year over the redshift range z=1.5-6, but we see evidence for a turn-down in the SFR distribution function above 2000 solar masses per year., 23 pages, forgot to note that it is in press at The Astrophysical Journal

A. Molino et al., The Advance Large Homogeneous Area Medium-Band Redshift Astronomical (ALHAMBRA) survey has observed eight different regions of the sky, including sections of the Cosmic Evolution Survey (COSMOS), DEEP2, European Large-Area Infrared Space Observatory Survey (ELAIS), Great Observatories Origins Deep Survey North (GOODS-N), Sloan Digital Sky Survey (SDSS) and Groth fields using a new photometric system with 20 optical, contiguous ~300-Å filters plus the JHKs bands. The filter system is designed to optimize the effective photometric redshift depth of the survey, while having enough wavelength resolution for the identification of faint emission lines. The observations, carried out with the Calar Alto 3.5-m telescope using the wide-field optical camera Large Area Imager for Calar Alto (LAICA) and the near-infrared (NIR) instrument Omega-2000, represent a total of ~700 h of on-target science images. Here we present multicolour point-spread function (PSF) corrected photometry and photometric redshifts for ~438 000 galaxies, detected in synthetic F814W images. The catalogues are complete down to a magnitude I~24.5AB and cover an effective area of 2.79 deg2. Photometric zero-points were calibrated using stellar transformation equations and refined internally, using a new technique based on the highly robust photometric redshifts measured for emission-line galaxies. We calculate Bayesian photometric redshifts with the Bayesian Photometric Redshift (BPZ)2.0 code, obtaining a precision of δz/(1+zs)=1 per cent for I, We acknowledge financial support from the Spanish MICINN under the Consolider-Ingenio 2010 Program grant CSD2006-00070: First Science with the GTC. Part of this work was supported by Junta de Andalucía, through grant TIC-114 and the Excellence Project P08-TIC-3531, and by the Spanish Ministry for Science and Innovation through grants AYA2006-1456, AYA2010-15169, AYA2010-22111-C03-02, AYA2010-22111-C03-01 and Generalitat Valenciana project Prometeo 2009/064.

We present results from a study of the photometric redshift performance of the Dark Energy Survey (DES), using the early data from a Science Verification (SV) period of observations in late 2012 and early 2013 that provided science-quality images for almost 200 sq.~deg.~at the nominal depth of the survey. We assess the photometric redshift performance using about 15000 galaxies with spectroscopic redshifts available from other surveys. These galaxies are used, in different configurations, as a calibration sample, and photo-$z$'s are obtained and studied using most of the existing photo-$z$ codes. A weighting method in a multi-dimensional color-magnitude space is applied to the spectroscopic sample in order to evaluate the photo-$z$ performance with sets that mimic the full DES photometric sample, which is on average significantly deeper than the calibration sample due to the limited depth of spectroscopic surveys. Empirical photo-$z$ methods using, for instance, Artificial Neural Networks or Random Forests, yield the best performance in the tests, achieving core photo-$z$ resolutions $\sigma_{68} \sim 0.08$. Moreover, the results from most of the codes, including template fitting methods, comfortably meet the DES requirements on photo-$z$ performance, therefore, providing an excellent precedent for future DES data sets., Comment: Published in MNRAS. This version accounts for minor comments in the journal review

We discuss the construction of the Galaxy And Mass Assembly (GAMA) 10h region (G10) using publicly available data in the Cosmic Evolution Survey region (COSMOS) in order to extend the GAMA survey to z~1 in a single ~1 deg^2 field. In order to obtain the maximum number of high precision spectroscopic redshifts we re-reduce all archival zCOSMOS-bright data and use the GAMA automatic cross-correlation redshift fitting code autoz. We use all available redshift information (autoz, zCOSMOS-bright 10k, PRIMUS, VVDS, SDSS and photometric redshifts) to calculate robust best-fit redshifts for all galaxies and visually inspect all 1D and 2D spectra to obtain 16,583 robust redshifts in the full COSMOS region. We then define the G10 region to be the central ~1deg^2 of COSMOS, which has relatively high spectroscopic completeness, and encompasses the CHILES VLA region. We define a combined r < 23.0mag & i < 22.0mag G10 sample (selected to have the highest bijective overlap) with which to perform future analysis, containing 9,861 sources with reliable high precision VLT-VIMOS spectra. All tables, spectra and imaging are available at: http://ict.icrar.org/cutout/G10 ., 16 pages, 15 figures, Accepted to MNRAS

We present the measurements of the redshift-space three-point correlation function (3PCF) for z~0.5 luminous red galaxies of the CMASS sample in the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey Data Release 11. The 3PCF measurements are interpreted within the halo occupation distribution framework using high-resolution N-body simulations, and the model successfully reproduces the 3PCF on scales larger than 1Mpc/h. As with the case for the redshift-space two-point correlation functions, we find that the redshift-space 3PCF measurements also favour the inclusion of galaxy velocity bias in the model. In particular, the central galaxy in a halo is on average in motion with respect to the core of the halo. We discuss the potential of the small-scale 3PCF to tighten the constraints on the relation between galaxies and dark matter haloes and on the phase-space distribution of galaxies., Comment: MNRAS Letter accepted

We describe the design and data analysis of the DEEP2 Galaxy Redshift Survey, the densest and largest high-precision redshift survey of galaxies at z ∼ 1 completed to date. The survey was designed to conduct a comprehensive census of massive galaxies, their properties, environments, and large-scale structure down to absolute magnitude MB = -20 at z ∼ 1 via ∼90 nights of observation on the Keck telescope. The survey covers an area of 2.8 deg2 divided into four separate fields observed to a limiting apparent magnitude of RAB = 24.1. Objects with z ≲ 0.7 are readily identifiable using BRI photometry and rejected in three of the four DEEP2 fields, allowing galaxies with z > 0.7 to be targeted ∼2.5 times more efficiently than in a purely magnitude-limited sample. Approximately 60% of eligible targets are chosen for spectroscopy, yielding nearly 53,000 spectra and more than 38,000 reliable redshift measurements. Most of the targets that fail to yield secure redshifts are blue objects that lie beyond z ∼ 1.45, where the [O II] 3727 Å doublet lies in the infrared. The DEIMOS 1200 line mm-1 grating used for the survey delivers high spectral resolution (R ∼ 6000), accurate and secure redshifts, and unique internal kinematic information. Extensive ancillary data are available in the DEEP2 fields, particularly in the Extended Groth Strip, which has evolved into one of the richest multiwavelength regions on the sky. This paper is intended as a handbook for users of the DEEP2 Data Release 4, which includes all DEEP2 spectra and redshifts, as well as for the DEEP2 DEIMOS data reduction pipelines. Extensive details are provided on object selection, mask design, biases in target selection and redshift measurements, the spec2d two-dimensional data-reduction pipeline, the spec1d automated redshift pipeline, and the zspec visual redshift verification process, along with examples of instrumental signatures or other artifacts that in some cases remain after data reduction. Redshift errors and catastrophic failure rates are assessed through more than 2000 objects with duplicate observations. Sky subtraction is essentially photon-limited even under bright OH sky lines; we describe the strategies that permitted this, based on high image stability, accurate wavelength solutions, and powerful B-spline modeling methods. We also investigate the impact of targets that appear to be single objects in ground-based targeting imaging but prove to be composite in Hubble Space Telescope data; they constitute several percent of targets at z ∼ 1, approaching ∼5%-10% at z > 1.5. Summary data are given that demonstrate the superiority of DEEP2 over other deep high-precision redshift surveys at z ∼ 1 in terms of redshift accuracy, sample number density, and amount of spectral information. We also provide an overview of the scientific highlights of the DEEP2 survey thus far. © 2013. The American Astronomical Society. All rights reserved.

We measure the luminosity and color dependence and the redshift evolution of galaxy clustering in the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey Ninth Data Release. We focus on the projected two-point correlation function (2PCF) of subsets of its CMASS sample, which includes about 260,000 galaxies over ~3,300 sq. deg in the redshift range 0.43, Comment: Accepted for publication in ApJ. Matched to the accepted version

We study the clustering of galaxies as function of luminosity and redshift in the range $0.35 < z < 1.25$ using data from the Advanced Large Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) survey. The ALHAMBRA data used in this work cover $2.38 \mathrm{deg}^2$ in 7 independent fields, after applying a detailed angular selection mask, with accurate photometric redshifts, $��_z \lesssim 0.014 (1+z)$, down to $I_{\rm AB} < 24$. Given the depth of the survey, we select samples in $B$-band luminosity down to $L^{\rm th} \simeq 0.16 L^{*}$ at $z = 0.9$. We measure the real-space clustering using the projected correlation function, accounting for photometric redshifts uncertainties. We infer the galaxy bias, and study its evolution with luminosity. We study the effect of sample variance, and confirm earlier results that the COSMOS and ELAIS-N1 fields are dominated by the presence of large structures. For the intermediate and bright samples, $L^{\rm med} \gtrsim 0.6L^{*}$, we obtain a strong dependence of bias on luminosity, in agreement with previous results at similar redshift. We are able to extend this study to fainter luminosities, where we obtain an almost flat relation, similar to that observed at low redshift. Regarding the evolution of bias with redshift, our results suggest that the different galaxy populations studied reside in haloes covering a range in mass between $\log_{10}[M_{\rm h}/(h^{-1}\mathrm{M}_{\odot})] \gtrsim 11.5$ for samples with $L^{\rm med} \simeq 0.3 L^{*}$ and $\log_{10}[M_{\rm h}/(h^{-1}\mathrm{M}_{\odot})] \gtrsim 13.0$ for samples with $L^{\rm med} \simeq 2 L^{*}$, with typical occupation numbers in the range of $\sim 1 - 3$ galaxies per halo., 21 pages, 16 figures, 3 tables. Accepted for publication in MNRAS. v2: matches accepted version. Small changes following referee comments, including addition of new fig. 11 and discussion on halo occupation numbers. Main results remain unchanged

[Aims]: We aim to illustrate the potentiality of the Advanced Large, Homogeneous Area, Medium-Band Redshift Astronomical (ALHAMBRA) survey to investigate the high-redshift universe through the detection of quasi stellar objects (QSOs) at redshifts higher than 5. [Methods]: We searched for QSOs candidates at high redshift by fitting an extensive library of spectral energy distributions-including active and non-active galaxy templates, as well as stars-to the photometric database of the ALHAMBRA survey (composed of 20 optical medium-band plus the 3 broad-band JHKs near-infrared filters). [Results]: Our selection over ≈1 square degree of ALHAMBRA data (∼1/4 of the total area covered by the survey), combined with GTC/OSIRIS spectroscopy, has yielded identification of an optically faint QSO at very high redshift (z = 5.41). The QSO has an absolute magnitude of ∼-24 at the 1450 Å continuum, a bolometric luminosity of ≈2 × 1046 erg s -1, and an estimated black hole mass of ≈108 M ⊙. This QSO adds itself to a reduced number of known UV faint sources at these redshifts. The preliminary derived space density is compatible with the most recent determinations of the high-z QSO luminosity functions. This new detection shows how ALHAMBRA, as well as forthcoming well-designed photometric surveys, can provide a wealth of information on the origin and early evolution of this kind of object. © 2013 ESO., Part of this work was supported by Junta de Andalucía, through grant TIC-114 and the Excellence Project P08-TIC-3531, and by the Spanish Ministry for Science and Innovation through grants AYA2006-1456, AYA2010-15169, and AYA2010-22111-C03-02, and Generalitat Valenciana project Prometeo 2008/132. M.P. acknowledges financial support from the JAE-Doc programme of the Spanish National Research Council (CSIC), co-funded by the European Social Fund.

Aims. We aim to illustrate the potentiality of the Advanced Large, Homogeneous Area, Medium-Band Redshift Astronomical (ALHAMBRA) survey to investigate the high-redshift universe through the detection of quasi stellar objects (QSOs) at redshifts higher than 5. Methods. We searched for QSOs candidates at high redshift by fitting an extensive library of spectral energy distributions – including active and non-active galaxy templates, as well as stars – to the photometric database of the ALHAMBRA survey (composed of 20 optical medium-band plus the 3 broad-band JHKs near-infrared filters). Results. Our selection over ≈1 square degree of ALHAMBRA data (∼1/4 of the total area covered by the survey), combined with GTC/OSIRIS spectroscopy, has yielded identification of an optically faint QSO at very high redshift (z = 5.41). The QSO has an absolute magnitude of ∼−24 at the 1450 Å continuum, a bolometric luminosity of ≈2 × 1046 erg s−1, and an estimated black hole mass of ≈108 M . This QSO adds itself to a reduced number of known UV faint sources at these redshifts. The preliminary derived space density is compatible with the most recent determinations of the high-z QSO luminosity functions. This new detection shows how ALHAMBRA, as well as forthcoming well-designed photometric surveys, can provide a wealth of information on the origin and early evolution of this kind of object. Junta de Andalucía TIC-114, P08-TIC-3531 Ministerio de España de Ciencias e Innovación AYA2006-1456 AYA2010-15169 AYA2010-22111-C03-02

We investigate the dependence of galaxy clustering on luminosity and stellar mass in the redshift range 0.5, Comment: 17 pages, 10 figures, 4 tables. Accepted for publication in A&A

[Context]: The connection between active galactic nuclei (AGN) and their host galaxies has been widely studied and found to be of great importance for providing answers to some fundamental questions related to AGN fuelling mechanisms, and both their formation and evolution. [Aims]: Using X-ray data and one of the deepest broad-band optical data sets available, we study how morphology and colours are related to X-ray properties for sources at redshifts z ≤ 2.0, using a sample of 262 AGN in the Subaru/XMM-Newton Deep Survey (SXDS). [Methods]: We performed our morphological classification using the galSVM code, which is a new method that is particularly suited to dealing with high-redshift sources. Colour-magnitude diagrams were studied in relationship to redshift, morphology, X-ray obscuration, and X-ray-to-optical flux ratio. We analysed the different regions in the colour-magnitude diagrams, and searched for correlations with the observed properties of AGN populations using models of their formation and evolution. [Results]: We confirm that a robust and reliable morphological classification of a general galaxy population at high redshift should be based on a multi-parametric approach. At least 50% of X-ray detected AGN at z ≤ 2.0 analysed in this work reside in spheroidal and bulge-dominated galaxies, while at least 18% have disk-dominated hosts. This suggests that different mechanisms may be responsible for triggering the nuclear activity. When analysing populations of X-ray detected AGN in both colour-magnitude and colour-stellar mass diagrams, the highest number of sources is found to reside in the green valley at redshifts ≈0.5-1.5. However, a larger number of low-luminosity AGN have been detected than in previous works owing to the substantial depth of the SXDS optical data. Whether AGN are hosted by early-or late-type galaxies, no clear relationship has been found with the optical colours (independently of redshift), as is typical of normal galaxies. Both early-and late-type AGN cover similar ranges of X-ray obscuration, for both unobscured and obscured sources. [Conclusions]: Our findings appear to confirm some previous suggestions that X-ray selected AGN residing in the green valley represent a transitional population, quenching star formation by means of different AGN feedback mechanisms and evolving to red-sequence galaxies. They might be hosted by similar sources (the majority of sources being late-type elliptical and lenticular galaxies, and early-type spirals) with similar stellar populations, which are triggered mainly by major and/or minor mergers, and in some cases by means of secular mechanism, as shown in previous numerical simulations. In the aforementioned transition we observe different phases of AGN activity, with some AGN being in the >QSO-mode> detected as compact, blue, and unobscured in X-rays, and with others passing through different phases before and after the >QSO-mode>, being obscured and unobscured in X-rays, respectively. © 2012 ESO., This work was supported by the Spanish Plan Nacional de Astronomía y Astrofísica under grant AYA2011-29517-C03-01. J.I.G.S. acknowledges financial support from the Spanish Ministry of Science and Innovation under project AYA2008-06311-C02-02. M.P. acknowledges Junta de Andalucía and Spanish Ministry of Science and Innovation through projects PO8-TIC-03531 and AYA2010-15169.

We determine the low-redshift field galaxy stellar mass function (GSMF) using an area of 143 deg2 from the first three years of the Galaxy And Mass Assembly (GAMA) survey. The magnitude limits of this redshift survey are r < 19.4 mag over two-thirds and 19.8 mag over one-third of the area. The GSMF is determined from a sample of 5210 galaxies using a density-corrected maximum volume method. This efficiently overcomes the issue of fluctuations in the number density versus redshift. With H0= 70 km s−1 Mpc−1, the GSMF is well described between 108 and 1011.5 M⊙ using a double Schechter function with Graphic, Graphic, α1=−0.35, Graphic and α2=−1.47. This result is more robust to uncertainties in the flow-model corrected redshifts than from the shallower Sloan Digital Sky Survey main sample (r < 17.8 mag). The upturn in the GSMF is also seen directly in the i-band and K-band galaxy luminosity functions. Accurately measuring the GSMF below 108 M⊙ is possible within the GAMA survey volume but as expected requires deeper imaging data to address the contribution from low surface-brightness galaxies.

Using deep narrowband and broadband imaging, we identify 401 z ≈ 0.40 and 249 z ≈ 0.49 Hαline-emitting galaxies in the Subaru Deep Field. Compared to other Hαsurveys at similar redshifts, our samples are unique since they probe lower Hαluminosities, are augmented with multi-wavelength (rest-frame 1000 -1.5 μm) coverage, and a large fraction (20%) of our samples has already been spectroscopically confirmed. Our spectra allow us to measure the Balmer decrement for nearly 60 galaxies with Hβ detected above 5σ. The Balmer decrements indicate an average extinction of A(Hα) = 0.7+1.4-0.7mag. We find that the Balmer decrement systematically increases with higher Hαluminosities and with larger stellar masses, in agreement with previous studies with sparser samples. We find that the star formation rates (SFRs) estimated from modeling the spectral energy distribution (SED) are reliable - we derived an "intrinsic" Hαluminosity which is then reddened assuming the color excess from SED modeling. The SED-predicted Hαluminosity agrees with Hαnarrowband measurements over 3dex (rms of 0.25dex). We then use the SED SFRs to test different statistically based dust corrections for Hαand find that adopting 1mag of extinction is inappropriate: galaxies with lower luminosities are less reddened. We find that the luminosity-dependent dust correction of Hopkins et al. yields consistent results over 3dex (rms of 0.3dex). Our comparisons are only possible by assuming that stellar reddening is roughly half of nebular reddening. The strong correspondence argues that with SED modeling, we can derive reliable intrinsic SFRs even in the absence of Hαmeasurements at z ∼ 0.5. © 2012. The American Astronomical Society. All rights reserved.

Using deep narrowband and broadband imaging, we identify 401 z ≈ 0.40 and 249 z ≈ 0.49 Hαline-emitting galaxies in the Subaru Deep Field. Compared to other Hαsurveys at similar redshifts, our samples are unique since they probe lower Hαluminosities, are augmented with multi-wavelength (rest-frame 1000 -1.5 μm) coverage, and a large fraction (20%) of our samples has already been spectroscopically confirmed. Our spectra allow us to measure the Balmer decrement for nearly 60 galaxies with Hβ detected above 5σ. The Balmer decrements indicate an average extinction of A(Hα) = 0.7+1.4-0.7mag. We find that the Balmer decrement systematically increases with higher Hαluminosities and with larger stellar masses, in agreement with previous studies with sparser samples. We find that the star formation rates (SFRs) estimated from modeling the spectral energy distribution (SED) are reliable - we derived an "intrinsic" Hαluminosity which is then reddened assuming the color excess from SED modeling. The SED-predicted Hαluminosity agrees with Hαnarrowband measurements over 3dex (rms of 0.25dex). We then use the SED SFRs to test different statistically based dust corrections for Hαand find that adopting 1mag of extinction is inappropriate: galaxies with lower luminosities are less reddened. We find that the luminosity-dependent dust correction of Hopkins et al. yields consistent results over 3dex (rms of 0.3dex). Our comparisons are only possible by assuming that stellar reddening is roughly half of nebular reddening. The strong correspondence argues that with SED modeling, we can derive reliable intrinsic SFRs even in the absence of Hαmeasurements at z ∼ 0.5. © 2012. The American Astronomical Society. All rights reserved.