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240 results on '"Jahnke, Knud"'

201. GEMS: Galaxy Evolution from Morphologies and SEDs

Author: Rix, Hans‐Walter, primary, Barden, Marco, additional, Beckwith, Steven V. W., additional, Bell, Eric F., additional, Borch, Andrea, additional, Caldwell, John A. R., additional, Haussler, Boris, additional, Jahnke, Knud, additional, Jogee, Shardha, additional, McIntosh, Daniel H., additional, Meisenheimer, Klaus, additional, Peng, Chien Y., additional, Sanchez, Sebastian F., additional, Somerville, Rachel S., additional, Wisotzki, Lutz, additional, and Wolf, Christian, additional
Published: 2004
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202. GEMS Imaging of Red-Sequence Galaxies at [FORMULA][F]z~0.7[/F][/FORMULA]: Dusty or Old?

Author: Bell, Eric F., primary, McIntosh, Daniel H., additional, Barden, Marco, additional, Wolf, Christian, additional, Caldwell, John A. R., additional, Rix, Hans-Walter, additional, Beckwith, Steven V. W., additional, Borch, Andrea, additional, Hussler, Boris, additional, Jahnke, Knud, additional, Jogee, Shardha, additional, Meisenheimer, Klaus, additional, Peng, Chien, additional, Sanchez, Sebastian F., additional, Somerville, Rachel S., additional, and Wisotzki, Lutz, additional
Published: 2003
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203. The Euclid mission design

Author: MacEwen, Howard A., Fazio, Giovanni G., Lystrup, Makenzie, Batalha, Natalie, Siegler, Nicholas, Tong, Edward C., Racca, Giuseppe D., Laureijs, René, Stagnaro, Luca, Salvignol, Jean-Christophe, Lorenzo Alvarez, José, Saavedra Criado, Gonzalo, Gaspar Venancio, Luis, Short, Alex, Strada, Paolo, Bönke, Tobias, Colombo, Cyril, Calvi, Adriano, Maiorano, Elena, Piersanti, Osvaldo, Prezelus, Sylvain, Rosato, Pierluigi, Pinel, Jacques, Rozemeijer, Hans, Lesna, Valentina, Musi, Paolo, Sias, Marco, Anselmi, Alberto, Cazaubiel, Vincent, Vaillon, Ludovic, Mellier, Yannick, Amiaux, Jérôme, Berthé, Michel, Sauvage, Marc, Azzollini, Ruyman, Cropper, Mark, Pottinger, Sabrina, Jahnke, Knud, Ealet, Anne, Maciaszek, Thierry, Pasian, Fabio, Zacchei, Andrea, Scaramella, Roberto, Hoar, John, Kohley, Ralf, Vavrek, Roland, Rudolph, Andreas, and Schmidt, Micha
Published: 2016
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204. Spectral energy distributions of type 1 AGN in XMM-COSMOS – II. Shape evolution.

Author: Hao, Heng, Elvis, Martin, Civano, Francesca, Zamorani, Gianni, Ho, Luis C., Comastri, Andrea, Brusa, Marcella, Bongiorno, Angela, Merloni, Andrea, Trump, Jonathan R., Salvato, Mara, Impey, Chris D., Koekemoer, Anton M., Lanzuisi, Giorgio, Celotti, Annalisa, Jahnke, Knud, Vignali, Cristian, Silverman, John D., Urry, C. Megan, and Schawinski, Kevin
Subjects: SPECTRAL energy distribution, GALACTIC nuclei, STELLAR luminosity function, QUASARS, X-rays, SPECTRUM analysis
Abstract: The mid-infrared-to-ultraviolet (0.1–10 μm) spectral energy distribution (SED) shapes of 407 X-ray-selected radio-quiet type 1 active galactic nuclei (AGN) in the wide-field ‘Cosmic Evolution Survey’ (COSMOS) have been studied for signs of evolution. For a sub-sample of 200 radio-quiet quasars with black hole mass estimates and host galaxy corrections, we studied their mean SEDs as a function of a broad range of redshift, bolometric luminosity, black hole mass and Eddington ratio, and compared them with the Elvis et al. (E94) type 1 AGN mean SED. We found that the mean SEDs in each bin are closely similar to each other, showing no statistical significant evidence of dependence on any of the analysed parameters. We also measured the SED dispersion as a function of these four parameters, and found no significant dependences. The dispersion of the XMM-COSMOS SEDs is generally larger than E94 SED dispersion in the ultraviolet, which might be due to the broader ‘window function’ for COSMOS quasars, and their X-ray-based selection. [ABSTRACT FROM AUTHOR]
Published: 2014

205. The environmental dependence of the structure of outer galactic discs in STAGES spiral galaxies.

Author: Maltby, David T., Gray, Meghan E., Aragón-Salamanca, Alfonso, Wolf, Christian, Bell, Eric F., Jogee, Shardha, Häußler, Boris, Barazza, Fabio D., Böhm, Asmus, and Jahnke, Knud
Subjects: SPIRAL galaxies, GALAXY clusters, GALACTIC evolution, IMAGING systems in astronomy, DISTRIBUTION of stars, STELLAR structure
Abstract: ABSTRACT We present an analysis of V-band radial surface brightness profiles for spiral galaxies from the field and cluster environments using Hubble Space Telescope/Advanced Camera for Surveys imaging and data from the Space Telescope A901/2 Galaxy Evolution Survey (STAGES). We use a large sample of ∼330 face-on to intermediately inclined spiral galaxies and assess the effect of the galaxy environment on the azimuthally averaged radial surface brightness μ profiles for each galaxy in the outer stellar disc (24 < μ < 26.5 mag arcsec−2). For galaxies with a purely exponential outer disc (∼50 per cent), we determine the significance of an environmental dependence on the outer disc scalelength hout. For galaxies with a broken exponential in their outer disc, either down-bending ( truncation, ∼10 per cent) or up-bending ( antitruncation, ∼40 per cent), we measure the strength T (outer-to-inner scalelength ratio, log10 hout/ hin) of the μ breaks and determine the significance of an environmental dependence on break strength T. Surprisingly, we find no evidence to suggest any such environmental dependence on either outer disc scalelength hout or break strength T, implying that the galaxy environment is not affecting the stellar distribution in the outer stellar disc. We also find that for galaxies with small effective radii ( re < 3 kpc) there is a lack of outer disc truncations in both the field and cluster environments. Our results suggest that the stellar distribution in the outer disc of spiral galaxies is not significantly affected by the galaxy environment. [ABSTRACT FROM AUTHOR]
Published: 2012
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206. GAS KINEMATICS IN Lyα NEBULAE.

Author: YUJIN YANG, ZABLUDOFF, ANN, JAHNKE, KNUD, EISENSTEIN, DANIEL, DAVE, ROMEEL, SHECTMAN, STEPHEN A., and KELSON, DANIEL D.
Subjects: KINEMATICS, NEBULA spectra, RADIATIVE transfer, GALACTIC redshift, GALAXY clusters, BINARY large objects
Abstract: Exploring the origin of Lyα nebulae ("blobs") at high redshift requires measurements of their gas kinematics that are impossible with only the resonant, optically thick Lyα line. To define gas motions relative to the systemic velocity of the blob, the Lyα line must be compared with an optically thin line like Hα λ6563, which is not much altered by radiative transfer effects and is more concentrated about the galaxies embedded in the nebula's core. We obtain optical and near-IR (NIR) spectra of the two brightest Lyα blobs (CDFS-LAB01 and CDFS-LAB02) from the Yang et al. sample using the Magellan/Magellan Echellette Spectrograph optical and Very Large Telescope/SINFONI NIR spectrographs. Both the Lyα and Hα lines confirm that these blobs lie at the survey redshift, z ~ 2.3. Within each blob, we detect several Hα sources, which roughly correspond to galaxies seen in Hubble Space Telescope rest-frame UV images. The Hα detections show that these galaxies have large internal velocity dispersions (σ v = 130-190 km s-1) and that, in the one system (LAB01), where we can reliably extract profiles for two Hα sources, their velocity difference is Δv ~ 440 km s-1. The presence of multiple galaxies within the blobs, and those galaxies' large velocity dispersions and large relative motion, is consistent with our previous finding that Lyα blobs inhabit massive dark matter halos that will evolve into those typical of present-day rich clusters and that the embedded galaxies may eventually become brightest cluster galaxies. To determine whether the gas near the embedded galaxies is predominantly infalling or outflowing, we compare the Lyα and Hα line centers, finding that Lyα is not offset (Δv Lyα = +0 km s-1) in LAB01 and redshifted by only +230 km s-1 in LAB02. These offsets are small compared to those of Lyman break galaxies, which average +450 km s-1 and extend to about +700 km s-1. In LAB02, we detect C II λ1334 and Si II λ1526 absorption lines, whose blueward shifts of ~200 km s-1 are consistent with the small outflow implied by the redward shift of Lyα. We test and rule out the simplest infall models and those outflow models with super/hyperwinds, which require large outflow velocities. Because of the unknown geometry of the gas distribution and the possibility of multiple sources of Lyα emission embedded in the blobs, a larger sample and more sophisticated models are required to test more complex or a wider range of infall and outflow scenarios. [ABSTRACT FROM AUTHOR]
Published: 2011
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207. Parametrizing arbitrary galaxy morphologies: potentials and pitfalls.

Author: Andrae, René, Jahnke, Knud, and Melchior, Peter
Subjects: *GALAXY clusters, *SIGNAL-to-noise ratio, *ASTRONOMICAL observations, *MORPHOLOGY, *LIGHT curves, *PARAMETER estimation, *DATA analysis, *INFORMATION asymmetry, *POTENTIAL theory (Physics)
Abstract: Given the enormous galaxy data bases of modern sky surveys, parametrizing galaxy morphologies is a very challenging task due to the huge number and variety of objects. We assess the different problems faced by existing parametrization schemes (CAS, Gini, , Sérsic profile, shapelets) in an attempt to understand why parametrization is so difficult and in order to suggest improvements for future parametrization schemes. We demonstrate that morphological observables (e.g. steepness of the radial light profile, ellipticity, asymmetry) are intertwined and cannot be measured independently of each other. We present strong arguments in favour of model-based parametrization schemes, namely reliability assessment, disentanglement of morphological observables and point spread function modelling. Furthermore, we demonstrate that estimates of the concentration and Sérsic index obtained from the Zurich Structure & Morphology catalogue are in excellent agreement with theoretical predictions. We also demonstrate that the incautious use of the concentration index for classification purposes can cause a severe loss of the discriminative information contained in a given data sample. Moreover, we show that, for poorly resolved galaxies, concentration index and suffer from strong discontinuities, i.e. similar morphologies are not necessarily mapped to neighbouring points in the parameter space. This limits the reliability of these parameters for classification purposes. Two-dimensional Sérsic profiles accounting for centroid and ellipticity are identified as the currently most reliable parametrization scheme in the regime of intermediate signal-to-noise ratios and resolutions, where asymmetries and substructures do not play an important role. We argue that basis functions provide good parametrization schemes in the regimes of high signal-to-noise ratios and resolutions. Concerning Sérsic profiles, we show that scale radii cannot be compared directly for profiles of different Sérsic indices. Furthermore, we show that parameter spaces are typically highly non-linear. This implies that significant caution is required when distance-based classification methods are used. [ABSTRACT FROM AUTHOR]
Published: 2011
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208. The environmental dependence of the stellar-mass–size relation in STAGES galaxies.

Author: Maltby, David T., Aragón-Salamanca, Alfonso, Gray, Meghan E., Barden, Marco, Häußler, Boris, Wolf, Christian, Peng, Chien Y., Jahnke, Knud, McIntosh, Daniel H., Böhm, Asmus, and van Kampen, Eelco
Subjects: ASTRONOMY, GALAXIES, STELLAR mass, SPIRAL galaxies, STELLAR evolution
Abstract: We present the stellar-mass–size relations for elliptical, lenticular and spiral galaxies in the field and cluster environments using Hubble Space Telescope/Advanced Camera for Surveys imaging and data from the Space Telescope A901/2 Galaxy Evolution Survey. We use a large sample of ∼1200 field and cluster galaxies and a sub-sample of cluster core galaxies, and quantify the significance of any putative environmental dependence on the stellar-mass–size relation. For elliptical, lenticular and high-mass spiral galaxies we find no evidence to suggest any such environmental dependence, implying that internal drivers are governing their size evolution. For intermediate-/low-mass spirals we find evidence, significant at the 2σ level, for a possible environmental dependence on galaxy sizes: the mean effective radius for lower mass spirals is ∼15–20 per cent larger in the field than in the cluster. This is due to a population of low-mass large- ae field spirals that are largely absent from the cluster environments. These large- ae field spirals contain extended stellar discs not present in their cluster counterparts. This suggests that the fragile extended stellar discs of these spiral galaxies may not survive the environmental conditions in the cluster. Our results suggest that internal physical processes are the main drivers governing the size evolution of galaxies, with the environment possibly playing a role affecting only the discs of intermediate-/low-mass spirals. [ABSTRACT FROM AUTHOR]
Published: 2010
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209. A weak lensing estimate from GEMS of the virial to stellar mass ratio in massive galaxies to z∼ 0.8.

Author: Heymans, Catherine, Bell, Eric F., Rix, Hans-Walter, Barden, Marco, Borch, Andrea, Caldwell, John A. R., McIntosh, Daniel H., Meisenheimer, Klaus, Peng, Chien Y., Wolf, Christian, Beckwith, Steven V. W., Häußler, Boris, Jahnke, Knud, Jogee, Shardha, Sánchez, Sebastian F., Somerville, Rachel, and Wisotzki, Lutz
Subjects: STELLAR mass, DENSITY of stars, GALAXIES, GALACTIC evolution, METAPHYSICAL cosmology
Abstract: We present constraints on the evolution of the virial to stellar mass ratio of galaxies with high stellar masses in the redshift range , by comparing weak lensing measurements of virial mass with estimates of stellar mass . For a complete sample of galaxies with , where the majority show an early-type morphology, we find that the virial mass to stellar mass ratio is given by . Assuming a baryon fraction from the concordance cosmology, this corresponds to a stellar fraction of baryons in massive galaxies of . Analysing the galaxy sample in different redshift slices, we find little or no evolution in the virial to stellar mass ratio, and place an upper limit of ∼2.5 on the growth of massive galaxies through the conversion of gas into stars from to the present day. [ABSTRACT FROM AUTHOR]
Published: 2006
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210. Cosmological weak lensing with the HST GEMS survey.

Author: Heymans, Catherine, Brown, Michael L., Barden, Marco, Caldwell, John A. R., Jahnke, Knud, Peng, Chien Y., Rix, Hans-Walter, Taylor, Andy, Beckwith, Steven V. W., Bell, Eric F., Borch, Andrea, Häußler, Boris, Jogee, Shardha, McIntosh, Daniel H., Meisenheimer, Klaus, Sánchez, Sebastian F., Somerville, Rachel, Wisotzki, Lutz, and Wolf, Christian
Subjects: GRAVITATIONAL lenses, MICROLENSING (Astrophysics), METAPHYSICAL cosmology, GALAXIES, SPECTRUM analysis
Abstract: We present our cosmic shear analysis of GEMS, one of the largest wide-field surveys ever undertaken by the Hubble Space Telescope. Imaged with the Advanced Camera for Surveys (ACS), GEMS spans 795 arcmin2 in the Chandra Deep Field South. We detect weak lensing by large-scale structure in high-resolution F606W GEMS data from ∼60 resolved galaxies per square arcminute. We measure the two-point shear correlation function, the top-hat shear variance and the shear power spectrum, performing an E/B mode decomposition for each statistic. We show that we are not limited by systematic errors and use our results to place joint constraints on the matter density parameter Ωm and the amplitude of the matter power spectrum σ8. We find where the 1σ error includes both our uncertainty on the median redshift of the survey and sampling variance. Removing image and point spread function (PSF) distortions are crucial to all weak lensing analyses. We therefore include a thorough discussion on the degree of ACS PSF distortion and anisotropy which we characterize directly from GEMS data. Consecutively imaged over 20 d, GEMS data also allow us to investigate PSF instability over time. We find that, even in the relatively short GEMS observing period, the ACS PSF ellipticity varies at the level of a few per cent which we account for with a semi-time-dependent PSF model. Our correction for the temporal and spatial variability of the PSF is shown to be successful through a series of diagnostic tests. [ABSTRACT FROM AUTHOR]
Published: 2005
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211. The B-band luminosities of quasar host galaxies.

Author: Jahnke, Knud and Wisotzki, Lutz
Subjects: *STELLAR luminosity function, *QUASARS, *GALAXIES, *ACTIVE galactic nuclei, *PHOTOMETRY
Abstract: We report on the analysis of B-band imaging data of 57 low-redshift quasi-stellar objects (quasars/QSOs) and Seyfert 1 galaxies selected from the Hamburg/ESO Survey, for which host-galaxy-dependent selection biases are greatly reduced compared with other optical surveys. Only one object in the sample is known to be radio-loud. We adopted a procedure to remove the active galactic nuclei (AGN) contribution by subtracting a scaled point spread function from each QSO image. To reclaim the integrated host galaxy flux we correct for oversubtraction based on simulations. This method is quite insensitive to the host galaxy morphological type, which we can unambiguously establish for 15 of the 57 objects. The quasar host galaxies are detected in all cases. The hosts are very luminous, ranging in absolute magnitude from −19.0 to −23.8, with an average of , considerably above for field galaxies. For the luminous QSO subsample with the average host absolute magnitude is , while for the complementary low-luminosity AGN we obtain , roughly equal to . The luminous host galaxies in the sample are typically ∼1 mag brighter than expected when inferring B-band luminosities from studies of similar objects at longer wavebands. We argue that this mismatch is not likely to be explained by selection effects, but favours host galaxy colours significantly bluer than those of inactive galaxies. Although published B-band data are scant, this result and the findings of other authors are in good agreement. [ABSTRACT FROM AUTHOR]
Published: 2003
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212. Euclid near infrared spectrophotometer instrument concept and first test results at the end of phase B

Author: Oschmann, Jacobus M., Clampin, Mark, Fazio, Giovanni G., MacEwen, Howard A., Maciaszek, Thierry, Ealet, Anne, Jahnke, Knud, Prieto, Eric, Barbier, Rémi, Mellier, Yannick, Costille, Anne, Ducret, Franck, Fabron, Christophe, Gimenez, Jean-Luc, Grange, Robert, Martin, Laurent, Rossin, Christelle, Pamplona, Tony, Vola, Pascal, Clémens, Jean Claude, Smadja, Gérard, Amiaux, Jérome, Barrière, Jean Christophe, Berthe, Michel, De Rosa, Adriano, Franceschi, Enrico, Morgante, Gianluca, Trifoglio, Massimo, Valenziano, Luca, Bonoli, Carlotta, Bortoletto, Favio, D'Alessandro, Maurizio, Corcione, Leonardo, Ligori, Sebastiano, Garilli, Bianca, Riva, Marco, Grupp, Frank, Vogel, Carolin, Hormuth, Felix, Seidel, Gregor, Wachter, Stefanie, Diaz, Jose Javier, Grañena, Ferran, Padilla, Cristobal, Toledo, Rafael, Lilje, Per B., Solheim, Bjarte G. B., Toulouse-Aastrup, Corinne, Andersen, Michael, Holmes, Warren, Israelsson, Ulf, Seiffert, Michael, Weber, Carissa, Waczynski, Augustyn, Laureijs, René J., Racca, Giuseppe, Salvignol, Jean-Christophe, and Strada, Paolo
Published: 2014
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213. LESS THAN 10 PERCENT OF STAR FORMATION IN z 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONS

Author: Robaina, Aday R., Bell, Eric F., Skelton, Rosalind E., McIntosh, Daniel H., Somerville, Rachel S., Zheng, Xianzhong, Rix, Walter, Bacon, David, Balogh, Michael, Barazza, Fabio D., Barden, Marco, Bohm, Asmus, R, John A., Gallazzi, Anna, Gray, Meghan E., Haussler, Boris, Heymans, Catherine, Jahnke, Knud, Jogee, Shardha, van, Eelco, Lane, Kyle, Meisenheimer, Klaus, Papovich, Casey, Peng, Chien Y., Sanchez, Sebastian F., Skibba, Ramin, Taylor, Andy, Wisotzki, Lutz, and Wolf, Christian
Abstract: Both observations and simulations show that major tidal interactions or mergers between gas-rich galaxies can lead to intense bursts of star formation. Yet, the average enhancement in star formation rate (SFR) in major mergers and the contribution of such events to the cosmic SFR are not well estimated. Here we use photometric redshifts, stellar masses, and UV SFRs from COMBO-17, 24 mm SFRs from Spitzer, and morphologies from two deep Hubble Space Telescope (HST) cosmological survey fields (ECDFS/GEMS and A901/STAGES) to study the enhancement in SFR as a function of projected galaxy separation. We apply two-point projected correlation function techniques, which we augment with morphologically selected very close pairs (separation <2'') and merger remnants from the HST imaging. Our analysis confirms that the most intensely star-forming systems are indeed interacting or merging. Yet, for massive (M * [?] 1010 M ) star-forming galaxies at 0.4 < z < 0.8, we find that the SFRs of galaxies undergoing a major interaction (mass ratios [?] 1:4 and separations [?] 40 kpc) are only 1.80 +- 0.30 times higher than the SFRs of non-interacting galaxies when averaged over all interactions and all stages of the interaction, in good agreement with other observational works. Our results also agree with hydrodynamical simulations of galaxy interactions, which produce some mergers with large bursts of star formation on [?]100 Myr timescales, but only a modest SFR enhancement when averaged over the entire merger timescale. We demonstrate that these results imply that only [?]10% of star formation at 0.4 [?] z [?] 0.8 is triggered directly by major mergers and interactions; these events are not important factors in the build-up of stellar mass since z = 1.
Published: 2009

214. THE COSMOS ACTIVE GALACTIC NUCLEUS SPECTROSCOPIC SURVEY. I. XMM-NEWTON COUNTERPARTS

Author: Trump, Jonathan R., Impey, Chris D., Elvis, Martin, McCarthy, Patrick J., Huchra, John P., Brusa, Marcella, Salvato, Mara, Capak, Peter, Cappelluti, Nico, Civano, Francesca, Comastri, Andrea, Gabor, Jared, Hao, Heng, Hasinger, Gunther, Jahnke, Knud, Kelly, Brandon C., Lilly, Simon J., Schinnerer, Eva, Scoville, Nick Z., and Smolcic, Vernesa
Abstract: We present optical spectroscopy for an X-ray and optical flux-limited sample of 677 XMM-Newton selected targets covering the 2 deg2 Cosmic Evolution Survey field, with a yield of 485 high-confidence redshifts. The majority of the spectra were obtained over three seasons (2005-2007) with the Inamori Magellan Areal Camera and Spectrograph instrument on the Magellan (Baade) telescope. We also include in the sample previously published Sloan Digital Sky Survey spectra and supplemental observations with MMT/Hectospec. We detail the observations and classification analyses. The survey is 90% complete to flux limits of f 0.5-10 keV > 8 x 10-16 erg cm-2 s-1 and i + AB < 22, where over 90% of targets have high-confidence redshifts. Making simple corrections for incompleteness due to redshift and spectral type allows for a description of the complete population to i + AB < 23. The corrected sample includes a 57% broad emission line (Type 1, unobscured) active galactic nucleus (AGN) at 0.13 < z < 4.26, 25% narrow emission line (Type 2, obscured) AGN at 0.07 < z < 1.29, and 18% absorption line (host-dominated, obscured) AGN at 0 < z < 1.22 (excluding the stars that made up 4% of the X-ray targets). We show that the survey's limits in X-ray and optical fluxes include nearly all X-ray AGNs (defined by L 0.5-10 keV > 3 x 1042 erg s-1) to z < 1, of both optically obscured and unobscured types. We find statistically significant evidence that the obscured-to-unobscured AGN ratio at z < 1 increases with redshift and decreases with luminosity.
Published: 2009

215. OBSCURED STAR FORMATION IN INTERMEDIATE-DENSITY ENVIRONMENTS: A SPITZER STUDY OF THE ABELL 901/902 SUPERCLUSTER

Author: Gallazzi, Anna, Bell, Eric F., Wolf, Christian, Gray, Meghan E., Papovich, Casey, Barden, Marco, Peng, Chien Y., Meisenheimer, Klaus, Heymans, Catherine, van, Eelco, Gilmour, Rachel, Balogh, Michael, McIntosh, Daniel H., Bacon, David, Barazza, Fabio D., Bohm, Asmus, R, John A., Haussler, Boris, Jahnke, Knud, Jogee, Shardha, Lane, Kyle, Robaina, Aday R., Sanchez, Sebastian F., Taylor, Andy, Wisotzki, Lutz, and Zheng, Xianzhong
Abstract: We explore the amount of obscured star formation as a function of environment in the Abell 901/902 (A901/902) supercluster at z = 0.165 in conjunction with a field sample drawn from the A901 and CDFS fields, imaged with the Hubble Space Telescope as part of the Space Telescope A901/902 Galaxy Evolution Survey and Galaxy Evolution from Morphology and Spectral Energy Distributions (SEDs) Survey. We combine the COMBO-17 near-UV/optical SED with Spitzer 24 m photometry to estimate both the unobscured and obscured star formation in galaxies with M * > 1010 M . We find that the star formation activity in massive galaxies is suppressed in dense environments, in agreement with previous studies. Yet, nearly 40% of the star-forming (SF) galaxies have red optical colors at intermediate and high densities. These red systems are not starbursting; they have star formation rates (SFRs) per unit stellar mass similar to or lower than blue SF galaxies. More than half of the red SF galaxies have low infrared-to-ultraviolet (IR-to-UV) luminosity ratios, relatively high Sersic indices, and they are equally abundant at all densities. They might be gradually quenching their star formation, possibly but not necessarily under the influence of gas-removing environmental processes. The other [?]40% of the red SF galaxies have high IR-to-UV luminosity ratios, indicative of high dust obscuration. They have relatively high specific SFRs and are more abundant at intermediate densities. Our results indicate that while there is an overall suppression in the SF galaxy fraction with density, the small amount of star formation surviving the cluster environment is to a large extent obscured, suggesting that environmental interactions trigger a phase of obscured star formation, before complete quenching.
Published: 2009

216. The Evolution of Early-Type Red Galaxies with the GEMS Survey: Luminosity-Size and Stellar Mass-Size Relations Since z = 1

Author: McIntosh, Daniel H., Bell, Eric F., Rix, Walter, Wolf, Christian, Heymans, Catherine, Peng, Chien Y., Somerville, Rachel S., Barden, Marco, W, Steven V., Borch, Andrea, R, John A., Haussler, Boris, Jahnke, Knud, Jogee, Shardha, Meisenheimer, Klaus, Sanchez, Sebastian F., and Wisotzki, Lutz
Abstract: We combine imaging from the Hubble Space Telescope Advanced Camera for Surveys, as part of the GEMS (Galaxy Evolution from Morphologies and SEDs) survey, with redshifts and rest-frame quantities from COMBO-17 to study the evolution of morphologically early-type galaxies with red colors since z = 1. From 0.deg5 x 0.deg5 imaging, we draw a large sample of 728 galaxies with centrally concentrated radial profiles (i.e., n [?] 2.5 from Sersic fits) and rest-frame (U - V) colors on the red sequence. We explore how the correlations of rest-frame V-band luminosity and of stellar mass with intrinsic half-light size change over the last half of cosmic time. By appropriate comparison with the well-defined local relations from the Sloan Digital Sky Survey, we find that the luminosity-size and stellar mass-size relations evolve in a manner that is consistent with the passive aging of ancient stellar populations. By itself, this result is consistent with a completely passive evolution of the red early-type galaxy population. If instead, as demonstrated by a number of recent surveys, the early-type galaxy population builds up in mass by roughly a factor of 2 since z ~ 1, our results imply that new additions to the early-type galaxy population follow similar luminosity-size and stellar mass-size correlations, compared to the older subset of early-type galaxies. Adding early-type galaxies to the red sequence through the fading of previously prominent disks appears to be consistent with the data. Through comparison with models, the role of dissipationless merging is limited to <1 major merger on average since z = 1 for the most massive galaxies. Predictions from models of gas-rich mergers are not yet mature enough to allow a detailed comparison to our observations. We find tentative evidence that the amount of luminosity evolution depends on galaxy stellar mass, such that the least massive galaxies show stronger luminosity evolution compared to more massive early types. This could reflect a different origin of low-mass early-type galaxies and/or younger stellar populations; the present data are insufficient to discriminate between these possibilities.
Published: 2005

217. Cosmology and Fundamental Physics with the Euclid Satellite

Author: Amendola, Luca, Appleby, Stephen, Bacon, David, Baker, Tessa, Baldi, Marco, Bartolo, Nicola, Blanchard, Alain, Bonvin, Camille, Borgani, Stefano, Branchini, Enzo, Burrage, Clare, Camera, Stefano, Carbone, Carmelita, Casarini, Luciano, Cropper, Mark, Rham, Claudia, Di Porto, Cinzia, Ealet, Anne, Ferreira, Pedro G., Finelli, Fabio, Garcia-Bellido, Juan, Giannantonio, Tommaso, Guzzo, Luigi, Heavens, Alan, Heisenberg, Lavinia, Heymans, Catherine, Hoekstra, Henk, Hollenstein, Lukas, Holmes, Rory, Horst, Ole, Jahnke, Knud, Kitching, Thomas D., Koivisto, Tomi, Kunz, Martin, La Vacca, Giuseppe, March, Marisa, Majerotto, Elisabetta, Markovic, Katarina, Marsh, David, Marulli, Federico, Massey, Richard, Mellier, Yannick, Mota, David F., Nunes, Nelson J., Percival, Will, Pettorino, Valeria, Porciani, Cristiano, Quercellini, Claudia, Read, Justin, Rinaldi, Massimiliano, Sapone, Domenico, Scaramella, Roberto, Constantinos Skordis, Simpson, Fergus, Taylor, Andy, Thomas, Shaun, Trotta, Roberto, Verde, Licia, Vernizzi, Filippo, Vollmer, Adrian, Wang, Yun, Weller, Jochen, Zlosnik, Tom, and Euclid Theory Working Grp

218. Inter-comparison of Radio-Loudness Criteria for Type 1 AGNs in the XMM-COSMOS Survey

Author: Hao, Heng, Sargent, Mark T., Elvis, Martin, Schinnerer, Eva, Zamorani, Gianni, Ho, Luis C., Donley, Jennifer L., Civano, Francesca, Smolcic, Vernesa, Celotti, Annalisa, Kuraszkiewicz, Joanna, Salvato, Mara, Brusa, Marcella, Capak, Peter, Carilli, Chris L., Comastri, Andrea, Impey, Chris D., Jahnke, Knud, Koekemoer, Anton M., Kevin Schawinski, Trump, Jonathan R., Urry, C. Megan, Vignali, Cristian, and Yun, Min
Subjects: Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, Astrophysics - Astrophysics of Galaxies
Abstract: Limited studies have been performed on the radio-loud fraction in X-ray selected type 1 AGN samples. The consistency between various radio-loudness definitions also needs to be checked. We measure the radio-loudness of the 407 type 1 AGNs in the XMM-COSMOS quasar sample using nine criteria from the literature (six defined in the rest-frame and three defined in the observed frame): $R_L=\log(L_{5GHz}/L_B)$, $q_{24}=\log(L_{24\mu m}/L_{1.4GHz})$, $R_{uv}=\log(L_{5GHz}/L_{2500\AA})$, $R_{i}=\log(L_{1.4GHz}/L_i)$, $R_X=\log(\nu L_{\nu}(5GHz)/L_X)$, $P_{5GHz}=\log(P_{5GHz}(W/Hz/Sr))$, $R_{L,obs}=\log(f_{1.4GHz}/f_B)$ (observed frame), $R_{i,obs}=\log(f_{1.4GHz}/f_i)$ (observed frame), and $q_{24, obs}=\log(f_{24\mu m}/f_{1.4GHz})$ (observed frame). Using any single criterion defined in the rest-frame, we find a low radio-loud fraction of $\lesssim 5\%$ in the XMM-COSMOS type 1 AGN sample, except for $R_{uv}$. Requiring that any two criteria agree reduces the radio-loud fraction to $\lesssim 2\%$ for about 3/4 of the cases. The low radio-loud fraction cannot be simply explained by the contribution of the host galaxy luminosity and reddening. The $P_{5GHz}=\log(P_{5GHz}(W/Hz/Sr))$ gives the smallest radio-loud fraction. Two of the three radio-loud fractions from the criteria defined in the observed frame without k-correction ($R_{L,obs}$ and $R_{i,obs}$) are much larger than the radio-loud fractions from other criteria., Comment: 12 pages, 7 figures, MNRAS submitted

219. 4MOST: Project overview and information for the First Call for Proposals

Author: De Jong, Roelof S., Agertz, Oscar, Berbel, Alex Agudo, Aird, James, Alexander, David A., Amarsi, Anish, Anders, Friedrich, Andrae, Rene, Ansarinejad, Behzad, Ansorge, Wolfgang, Antilogus, Pierre, Anwand-Heerwart, Heiko, Arentsen, Anke, Arnadottir, Anna, Asplund, Martin, Auger, Matt, Azais, Nicolas, Baade, Dietrich, Baker, Gabriella, Baker, Sufyan, Balbinot, Eduardo, Baldry, Ivan K., Banerji, Manda, Barden, Samuel, Barklem, Paul, Barthélémy-Mazot, Eléonore, Battistini, Chiara, Bauer, Svend, Bell, Cameron P. M., Bellido-Tirado, Olga, Bellstedt, Sabine, Belokurov, Vasily, Bensby, Thomas, Bergemann, Maria, Bestenlehner, Joachim M., Bielby, Richard, Bilicki, Maciej, Blake, Chris, Bland-Hawthorn, Joss, Boeche, Corrado, Boland, Wilfried, Boller, Thomas, Bongard, Sebastien, Bongiorno, Angela, Bonifacio, Piercarlo, Boudon, Didier, Brooks, David, Brown, Michael J. I., Brown, Rebecca, Brüggen, Marcus, Brynnel, Joar, Brzeski, Jurek, Buchert, Thomas, Buschkamp, Peter, Caffau, Elisabetta, Caillier, Patrick, Carrick, Jonathan, Casagrande, Luca, Case, Scott, Casey, Andrew, Cesarini, Isabella, Cescutti, Gabriele, Chapuis, Diane, Chiappini, Cristina, Childress, Michael, Christlieb, Norbert, Church, Ross, Cioni, Maria-Rosa L., Cluver, Michelle, Colless, Matthew, Collett, Thomas, Comparat, Johan, Cooper, Andrew, Couch, Warrick, Courbin, Frederic, Croom, Scott, Croton, Darren, Daguisé, Eric, Dalton, Gavin, Davies, Luke J. M., Davis, Tamara, De Laverny, Patrick, Deason, Alis, Dionies, Frank, Disseau, Karen, Doel, Peter, Döscher, Daniel, Driver, Simon P., Dwelly, Tom, Eckert, Dominique, Edge, Alastair, Edvardsson, Bengt, Youssoufi, Dalal El, Elhaddad, Ahmed, Enke, Harry, Erfanianfar, Ghazaleh, Farrell, Tony, Fechner, Thomas, Feiz, Carmen, Feltzing, Sofia, Ferreras, Ignacio, Feuerstein, Dietrich, Feuillet, Diane, Finoguenov, Alexis, Ford, Dominic, Fotopoulou, Sotiria, Fouesneau, Morgan, Frenk, Carlos, Frey, Steffen, Gaessler, Wolfgang, Geier, Stephan, Fusillo, Nicola Gentile, Gerhard, Ortwin, Giannantonio, Tommaso, Giannone, Domenico, Gibson, Brad, Gillingham, Peter, González-Fernández, Carlos, Gonzalez-Solares, Eduardo, Gottloeber, Stefan, Gould, Andrew, Grebel, Eva K., Gueguen, Alain, Guiglion, Guillaume, Haehnelt, Martin, Hahn, Thomas, Hansen, Camilla J., Hartman, Henrik, Hauptner, Katja, Hawkins, Keith, Haynes, Dionne, Haynes, Roger, Heiter, Ulrike, Helmi, Amina, Aguayo, Cesar Hernandez, Hewett, Paul, Hinton, Samuel, Hobbs, David, Hoenig, Sebastian, Hofman, David, Hook, Isobel, Hopgood, Joshua, Hopkins, Andrew, Hourihane, Anna, Howes, Louise, Howlett, Cullan, Huet, Tristan, Irwin, Mike, Iwert, Olaf, Jablonka, Pascale, Jahn, Thomas, Jahnke, Knud, Jarno, Aurélien, Jin, Shoko, Jofre, Paula, Johl, Diana, Jones, Damien, Jönsson, Henrik, Jordan, Carola, Karovicova, Iva, Khalatyan, Arman, Kelz, Andreas, Kennicutt, Robert, King, David, Kitaura, Francisco, Klar, Jochen, Klauser, Urs, Kneib, Jean-Paul, Koch, Andreas, Koposov, Sergey, Kordopatis, Georges, Korn, Andreas, Kosmalski, Johan, Kotak, Rubina, Kovalev, Mikhail, Kreckel, Kathryn, Kripak, Yevgen, Krumpe, Mirko, Kuijken, Koen, Kunder, Andrea, Kushniruk, Iryna, Lam, Man I, Lamer, Georg, Laurent, Florence, Lawrence, Jon, Lehmitz, Michael, Lemasle, Bertrand, Lewis, James, Li, Baojiu, Lidman, Chris, Lind, Karin, Liske, Jochen, Lizon, Jean-Louis, Loveday, Jon, Ludwig, Hans-Günter, McDermid, Richard M., Maguire, Kate, Mainieri, Vincenzo, Mali, Slavko, Mandel, Holger, Mandel, Kaisey, Mannering, Liz, Martell, Sarah, Delgado, David Martinez, Matijevic, Gal, McGregor, Helen, McMahon, Richard, McMillan, Paul, Mena, Olga, Merloni, Andrea, Meyer, Martin J., Michel, Christophe, Micheva, Genoveva, Migniau, Jean-Emmanuel, Minchev, Ivan, Monari, Giacomo, Muller, Rolf, Murphy, David, Muthukrishna, Daniel, Nandra, Kirpal, Navarro, Ramon, Ness, Melissa, Nichani, Vijay, Nichol, Robert, Nicklas, Harald, Niederhofer, Florian, Norberg, Peder, Obreschkow, Danail, Oliver, Seb, Owers, Matt, Pai, Naveen, Pankratow, Sergei, Parkinson, David, Paschke, Jens, Paterson, Robert, Pecontal, Arlette, Parry, Ian, Phillips, Dan, Pillepich, Annalisa, Pinard, Laurent, Pirard, Jeff, Piskunov, Nikolai, Plank, Volker, Plüschke, Dennis, Pons, Estelle, Popesso, Paola, Power, Chris, Pragt, Johan, Pramskiy, Alexander, Pryer, Dan, Quattri, Marco, Queiroz, Anna Barbara De Andrade, Quirrenbach, Andreas, Rahurkar, Swara, Raichoor, Anand, Ramstedt, Sofia, Rau, Arne, Recio-Blanco, Alejandra, Reiss, Roland, Renaud, Florent, Revaz, Yves, Rhode, Petra, Richard, Johan, Richter, Amon David, Rix, Hans-Walter, Robotham, Aaron S. G., Roelfsema, Ronald, Romaniello, Martino, Rosario, David, Rothmaier, Florian, Roukema, Boudewijn, Ruchti, Gregory, Rupprecht, Gero, Rybizki, Jan, Ryde, Nils, Saar, Andre, Sadler, Elaine, Sahlén, Martin, Salvato, Mara, Sassolas, Benoit, Saunders, Will, Saviauk, Allar, Sbordone, Luca, Schmidt, Thomas, Schnurr, Olivier, Scholz, Ralf-Dieter, Schwope, Axel, Seifert, Walter, Shanks, Tom, Sheinis, Andrew, Sivov, Tihomir, Skúladóttir, Ása, Smartt, Stephen, Smedley, Scott, Smith, Greg, Smith, Robert, Sorce, Jenny, Spitler, Lee, Starkenburg, Else, Steinmetz, Matthias, Stilz, Ingo, Storm, Jesper, Sullivan, Mark, Sutherland, William, Swann, Elizabeth, Tamone, Amélie, Taylor, Edward N., Teillon, Julien, Tempel, Elmo, Ter Horst, Rik, Thi, Wing-Fai, Tolstoy, Eline, Trager, Scott, Traven, Gregor, Tremblay, Pier-Emmanuel, Tresse, Laurence, Valentini, Marica, Van De Weygaert, Rien, Van Den Ancker, Mario, Veljanoski, Jovan, Venkatesan, Sudharshan, Wagner, Lukas, Wagner, Karl, Walcher, C. Jakob, Waller, Lew, Walton, Nicholas, Wang, Lingyu, Winkler, Roland, Wisotzki, Lutz, Worley, C. Clare, Worseck, Gabor, Xiang, Maosheng, Xu, Wenli, Yong, David, Zhao, Cheng, Zheng, Jessica, Zscheyge, Florian, and Zucker, Daniel
Subjects: 010308 nuclear & particles physics, 0103 physical sciences, 010303 astronomy & astrophysics, 01 natural sciences
Abstract: We introduce the 4-metre Multi-Object Spectroscopic Telescope (4MOST), a new high-multiplex, wide-field spectroscopic survey facility under development for the four-metre-class Visible and Infrared Survey Telescope for Astronomy (VISTA) at Paranal. Its key specifications are: a large field of view (FoV) of 4.2 square degrees and a high multiplex capability, with 1624 fibres feeding two low-resolution spectrographs (R = λ/Δλ ~ 6500), and 812 fibres transferring light to the high-resolution spectrograph (R ~ 20 000). After a description of the instrument and its expected performance, a short overview is given of its operational scheme and planned 4MOST Consortium science; these aspects are covered in more detail in other articles in this edition of The Messenger. Finally, the processes, schedules, and policies concerning the selection of ESO Community Surveys are presented, commencing with a singular opportunity to submit Letters of Intent for Public Surveys during the first five years of 4MOST operations., Published in The Messenger vol. 175, pp. 3-11, March 2019.

220. The STAGES view of red spirals and dusty red galaxies: mass-dependent quenching of star formation in cluster infall

Author: Wolf, Christian, Aragón-Salamanca, Alfonso, Balogh, Michael, Barden, Marco, Bell, Eric F., Gray, Meghan E., Peng, Chien Y., Bacon, David, Barazza, Fabio D., Böhm, Asmus, Caldwell, John A. R., Gallazzi, Anna, Häußler, Boris, Heymans, Catherine, Jahnke, Knud, Jogee, Shardha, Van Kampen, Eelco, Lane, Kyle, McIntosh, Daniel H., Meisenheimer, Klaus, Papovich, Casey, Sánchez, Sebastian F., Taylor, Andy, Wisotzki, Lutz, Zheng, Xianzhong, Wolf, Christian, Aragón-Salamanca, Alfonso, Balogh, Michael, Barden, Marco, Bell, Eric F., Gray, Meghan E., Peng, Chien Y., Bacon, David, Barazza, Fabio D., Böhm, Asmus, Caldwell, John A. R., Gallazzi, Anna, Häußler, Boris, Heymans, Catherine, Jahnke, Knud, Jogee, Shardha, Van Kampen, Eelco, Lane, Kyle, McIntosh, Daniel H., Meisenheimer, Klaus, Papovich, Casey, Sánchez, Sebastian F., Taylor, Andy, Wisotzki, Lutz, and Zheng, Xianzhong
Abstract: We investigate the properties of optically passive spirals and dusty red galaxies in the A901/2 cluster complex at redshift ∼0.17 using rest-frame near-ultraviolet-optical spectral energy distributions, 24-μm infrared data and Hubble Space Telescope morphologies from the STAGES data set. The cluster sample is based on COMBO-17 redshifts with an rms precision of σcz≈ 2000 km s−1. We find that ‘dusty red galaxies' and ‘optically passive spirals' in A901/2 are largely the same phenomenon, and that they form stars at a substantial rate, which is only four times lower than that in blue spirals at fixed mass. This star formation is more obscured than in blue galaxies and its optical signatures are weak. They appear predominantly in the stellar mass range of log M*/M⊙=[10, 11] where they constitute over half of the star-forming galaxies in the cluster; they are thus a vital ingredient for understanding the overall picture of star formation quenching in clusters. We find that the mean specific star formation rate (SFR) of star-forming galaxies in the cluster is clearly lower than in the field, in contrast to the specific SFR properties of blue galaxies alone, which appear similar in cluster and field. Such a rich red spiral population is best explained if quenching is a slow process and morphological transformation is delayed even more. At log M*/M⊙ < 10, such galaxies are rare, suggesting that their quenching is fast and accompanied by morphological change. We note that edge-on spirals play a minor role; despite being dust reddened they form only a small fraction of spirals independent of environment

221. The environmental dependence of the structure of outer galactic discs in STAGES spiral galaxies

Author: Maltby, David T., Gray, Meghan E., Aragón-Salamanca, Alfonso, Wolf, Christian, Bell, Eric F., Jogee, Shardha, Häußler, Boris, Barazza, Fabio D., Böhm, Asmus, Jahnke, Knud, Maltby, David T., Gray, Meghan E., Aragón-Salamanca, Alfonso, Wolf, Christian, Bell, Eric F., Jogee, Shardha, Häußler, Boris, Barazza, Fabio D., Böhm, Asmus, and Jahnke, Knud
Abstract: We present an analysis of V-band radial surface brightness profiles for spiral galaxies from the field and cluster environments using Hubble Space Telescope/Advanced Camera for Surveys imaging and data from the Space Telescope A901/2 Galaxy Evolution Survey (STAGES). We use a large sample of ∼330 face-on to intermediately inclined spiral galaxies and assess the effect of the galaxy environment on the azimuthally averaged radial surface brightness μ profiles for each galaxy in the outer stellar disc (24 < μ < 26.5 mag arcsec−2). For galaxies with a purely exponential outer disc (∼50 per cent), we determine the significance of an environmental dependence on the outer disc scalelength hout. For galaxies with a broken exponential in their outer disc, either down-bending (truncation, ∼10 per cent) or up-bending (antitruncation, ∼40 per cent), we measure the strength T (outer-to-inner scalelength ratio, log10 hout/hin) of the μ breaks and determine the significance of an environmental dependence on break strength T. Surprisingly, we find no evidence to suggest any such environmental dependence on either outer disc scalelength hout or break strength T, implying that the galaxy environment is not affecting the stellar distribution in the outer stellar disc. We also find that for galaxies with small effective radii (re < 3 kpc) there is a lack of outer disc truncations in both the field and cluster environments. Our results suggest that the stellar distribution in the outer disc of spiral galaxies is not significantly affected by the galaxy environment

222. The dark matter environment of the Abell 901/902 supercluster: a weak lensing analysis of the HST STAGES survey

Author: Heymans, Catherine, Gray, Meghan E., Peng, Chien Y., Van Waerbeke, Ludovic, Bell, Eric F., Wolf, Christian, Bacon, David, Balogh, Michael, Barazza, Fabio D., Barden, Marco, Böhm, Asmus, Caldwell, John A. R., Häußler, Boris, Jahnke, Knud, Jogee, Shardha, Van Kampen, Eelco, Lane, Kyle, McIntosh, Daniel H., Meisenheimer, Klaus, Mellier, Yannick, Sánchez, Sebastian F., Taylor, Andy N., Wisotzki, Lutz, Zheng, Xianzhong, Heymans, Catherine, Gray, Meghan E., Peng, Chien Y., Van Waerbeke, Ludovic, Bell, Eric F., Wolf, Christian, Bacon, David, Balogh, Michael, Barazza, Fabio D., Barden, Marco, Böhm, Asmus, Caldwell, John A. R., Häußler, Boris, Jahnke, Knud, Jogee, Shardha, Van Kampen, Eelco, Lane, Kyle, McIntosh, Daniel H., Meisenheimer, Klaus, Mellier, Yannick, Sánchez, Sebastian F., Taylor, Andy N., Wisotzki, Lutz, and Zheng, Xianzhong
Abstract: We present a high-resolution dark matter reconstruction of the z= 0.165 Abell 901/902 supercluster from a weak lensing analysis of the Hubble Space Telescope STAGES survey. We detect the four main structures of the supercluster at high significance, resolving substructure within and between the clusters. We find that the distribution of dark matter is well traced by the cluster galaxies, with the brightest cluster galaxies marking out the strongest peaks in the dark matter distribution. We also find a significant extension of the dark matter distribution of Abell 901a in the direction of an infalling X-ray group Abell 901α. We present mass, mass-to-light and mass-to-stellar mass ratio measurements of the structures and substructures that we detect. We find no evidence for variation of the mass-to-light and mass-to-stellar mass ratio between the different clusters. We compare our space-based lensing analysis with an earlier ground-based lensing analysis of the supercluster to demonstrate the importance of space-based imaging for future weak lensing dark matter ‘observations'

223. STAGES: the Space Telescope A901/2 Galaxy Evolution Survey

Author: Gray, Meghan E., Wolf, Christian, Barden, Marco, Peng, Chien Y., Häußler, Boris, Bell, Eric F., McIntosh, Daniel H., Guo, Yicheng, Caldwell, John A. R., Bacon, David, Balogh, Michael, Barazza, Fabio D., Böhm, Asmus, Heymans, Catherine, Jahnke, Knud, Jogee, Shardha, Van Kampen, Eelco, Lane, Kyle, Meisenheimer, Klaus, Sánchez, Sebastian F., Taylor, Andy, Wisotzki, Lutz, Zheng, Xianzhong, Green, David A., Beswick, R. J., Saikia, D. J., Gilmour, Rachel, Johnson, Benjamin D., Papovich, Casey, Gray, Meghan E., Wolf, Christian, Barden, Marco, Peng, Chien Y., Häußler, Boris, Bell, Eric F., McIntosh, Daniel H., Guo, Yicheng, Caldwell, John A. R., Bacon, David, Balogh, Michael, Barazza, Fabio D., Böhm, Asmus, Heymans, Catherine, Jahnke, Knud, Jogee, Shardha, Van Kampen, Eelco, Lane, Kyle, Meisenheimer, Klaus, Sánchez, Sebastian F., Taylor, Andy, Wisotzki, Lutz, Zheng, Xianzhong, Green, David A., Beswick, R. J., Saikia, D. J., Gilmour, Rachel, Johnson, Benjamin D., and Papovich, Casey
Abstract: We present an overview of the Space Telescope A901/2 Galaxy Evolution Survey (STAGES). STAGES is a multiwavelength project designed to probe physical drivers of galaxy evolution across a wide range of environments and luminosity. A complex multicluster system at z∼ 0.165 has been the subject of an 80-orbit F606W Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) mosaic covering the full span of the supercluster. Extensive multiwavelength observations with XMM-Newton, GALEX, Spitzer, 2dF, Giant Metrewave Radio Telescope and the 17-band COMBO-17 photometric redshift survey complement the HST imaging. Our survey goals include simultaneously linking galaxy morphology with other observables such as age, star formation rate, nuclear activity and stellar mass. In addition, with the multiwavelength data set and new high-resolution mass maps from gravitational lensing, we are able to disentangle the large-scale structure of the system. By examining all aspects of an environment we will be able to evaluate the relative importance of the dark matter haloes, the local galaxy density and the hot X-ray gas in driving galaxy transformation. This paper describes the HST imaging, data reduction and creation of a master catalogue. We perform the Sérsic fitting on the HST images and conduct associated simulations to quantify completeness. In addition, we present the COMBO-17 photometric redshift catalogue and estimates of stellar masses and star formation rates for this field. We define galaxy and cluster sample selection criteria, which will be the basis for forthcoming science analyses, and present a compilation of notable objects in the field. Finally, we describe the further multiwavelength observations and announce public access to the data and catalogues

224. A new automatic method to identify galaxy mergers - I. Description and application to the Space Telescope A901/902 Galaxy Evolution Survey

Author: Hoyos, Carlos, Aragón-Salamanca, Alfonso, Gray, Meghan E., Maltby, David T., Bell, Eric F., Barazza, Fabio D., Böhm, Asmus, Häußler, Boris, Jahnke, Knud, Jogee, Shardha, Lane, Kyle P., McIntosh, Daniel H., Wolf, Christian, Hoyos, Carlos, Aragón-Salamanca, Alfonso, Gray, Meghan E., Maltby, David T., Bell, Eric F., Barazza, Fabio D., Böhm, Asmus, Häußler, Boris, Jahnke, Knud, Jogee, Shardha, Lane, Kyle P., McIntosh, Daniel H., and Wolf, Christian
Abstract: We present a new automatic method to identify galaxy mergers using the morphological information contained in the residual images of galaxies after the subtraction of a smooth Sérsic model. The removal of the bulk signal from the host galaxy light is done with the aim of detecting the much fainter and elusive minor mergers. The specific morphological parameters that are used in the merger diagnostic suggested here are the residual flux fraction (RFF) and the asymmetry of the residuals [A(Res)]. The new diagnostic has been calibrated and optimized so that the resulting merger sample is very complete. However, the contamination by non-mergers is also high. If the same optimization method is adopted for combinations of other structural parameters such as the Concentration, Asymmetry, clumpineSs (CAS) system, the merger indicator we introduce yields merger samples of equal or higher statistical quality than the samples obtained through the use of other structural parameters. We investigate the ability of the method presented here to select minor mergers by identifying a sample of visually classified mergers that would not have been picked up by the use of the CAS system, when using its usual limits. However, given the low prevalence of mergers among the general population of galaxies and the optimization used here, we find that the merger diagnostic introduced in this work is best used as a negative merger test, that is, it is very effective at selecting non-merging galaxies. In common with all the currently available automatic methods, the sample of merger candidates selected is heavily contaminated by non-mergers, and further steps are needed to produce a clean merger sample. This merger diagnostic has been developed using the Hubble Space Telescope/ACS F606W images of the A901/902 multiple cluster system (z= 0.165) obtained by the Space Telescope A901/902 Galaxy Evolution Survey team. In particular, we have focused on a mass- and magnitude-limited sample (log M/M⊙ >

225. Mission-level performance verification approach for the Euclid space mission

Author: Angeli, George Z., Dierickx, Philippe, Vavrek, Roland D., Laureijs, René J., Lorenzo Alvarez, Jose, Amiaux, Jérôme, Mellier, Yannick, Azzollini, Ruyman, Buenadicha, Guillermo, Saavedra Criado, Gonzalo, Cropper, Mark, Dabin, Christophe, Ealet, Anne, Garilli, Bianca, Gregorio, Anna, Hoekstra, Henk, Jahnke, Knud, Kilbinger, Martin, Kitching, Tom, Hoar, John, Percival, Will, Racca, Giuseppe D., Salvignol, Jean-Christophe, Sauvage, Marc, Scaramella, Roberto, Gaspar Venancio, Luis M., Wang, Yun, Zacchei, Andrea, and Wachter, Stefanie
Published: 2016
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226. THE BULK OF THE BLACK HOLE GROWTH SINCE z ∼ 1 OCCURS IN A SECULAR UNIVERSE: NO MAJOR MERGER-AGN CONNECTION.

Author: Cisternas, Mauricio, Jahnke, Knud, Inskip, Katherine J., Kartaltepe, Jeyhan, Koekemoer, Anton M., Lisker, Thorsten, Robaina, Aday R., Scodeggio, Marco, Sheth, Kartik, Trump, Jonathan R., Andrae, René, Miyaji, Takamitsu, Lusso, Elisabeta, Brusa, Marcella, Capak, Peter, Cappelluti, Nico, Civano, Francesca, Ilbert, Olivier, Impey, Chris D., and Leauthaud, Alexie
Published: 2011
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227. LESS THAN 10 PERCENT OF STAR FORMATION IN z ∼ 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONS.

Author: Robaina, Aday R., Bell, Eric F., Skelton, Rosalind E., McIntosh, Daniel H., Somerville, Rachel S., Zheng, Xianzhong, Rix, Hans-Walter, Bacon, David, Balogh, Michael, Barazza, Fabio D., Barden, Marco, Böhm, Asmus, Caldwell, John A. R., Gallazzi, Anna, Gray, Meghan E., Häussler, Boris, Heymans, Catherine, Jahnke, Knud, Jogee, Shardha, and van Kampen, Eelco
Published: 2009
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228. Quasars Do Not Live in Merging Systems: No Enhanced Merger Rate at z≲0.8.

Author: Cisternas, Mauricio, Jahnke, Knud, and Inskip, Katherine J.
Abstract: We tackle the long-standing question “what is the relevance of major mergers and interactions as triggering mechanisms for AGN activity?” We study a sample of 83 quasars over z ~ 0.3–1.0 with high-resolution HST/ACS imaging in the F814W (broad I) band in the COSMOS field (Scoville et al. 2007), detected by their X-ray emission in the XMM-Newton survey (Hasinger et al. 2007). We perform a visual analysis of their morphologies, looking for signatures of merging and interactions in their host galaxies that could potentially be related to the AGN fueling mechanism. To get the best possible picture of the host galaxies, we remove the bright quasar by modeling each of them as a Sersic surface brightness profile plus a central point source, through a 2-D parametric fit. [ABSTRACT FROM PUBLISHER]
Published: 2009
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229. No Evolution in the MBH–M*,total Relation Over the Last 9 Gyrs.

Author: Jahnke, Knud, Cisternas, Mauricio, and Inskip, Katherine J.
Abstract: We investigate 10 QSO host galaxies at 1
Published: 2009
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230. GEMS Imaging of Red-Sequence Galaxies at ∼ 0.7: Dusty or Old?

Author: Bell, Eric F., McIntosh, Daniel H., Barden, Marco, Wolf, Christian, Caldwell, John A. R., Rix, Hans-Walter, Beckwith, Steven V. W., Borch, Andrea, Häussler, Boris, Jahnke, Knud, Jogee, Shardha, Meisenheimer, Klaus, Peng, Chien, Sanchez, Sebastian F., Somerville, Rachel S., and Wisotzki, Lutz
Published: 2004
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231. THE BULK OF THE BLACK HOLE GROWTH SINCE z 1 OCCURS IN A SECULAR UNIVERSE: NO MAJOR MERGER-AGN CONNECTION

Author: Cisternas, Mauricio, Jahnke, Knud, Inskip, Katherine J., Kartaltepe, Jeyhan, Koekemoer, Anton M., Lisker, Thorsten, Robaina, Aday R., Scodeggio, Marco, Sheth, Kartik, Trump, Jonathan R., Andrae, Rene, Miyaji, Takamitsu, Lusso, Elisabeta, Brusa, Marcella, Capak, Peter, Cappelluti, Nico, Civano, Francesca, Ilbert, Olivier, Impey, Chris D., Leauthaud, Alexie, Lilly, Simon J., Salvato, Mara, Scoville, Nick Z., and Taniguchi, Yoshi
Abstract: What is the relevance of major mergers and interactions as triggering mechanisms for active galactic nuclei (AGNs) activity? To answer this long-standing question, we analyze 140 XMM-Newton-selected AGN host galaxies and a matched control sample of 1264 inactive galaxies over z [?] 0.3-1.0 and M * < 1011.7 M with high-resolution Hubble Space Telescope/Advanced Camera for Surveys imaging from the COSMOS field. The visual analysis of their morphologies by 10 independent human classifiers yields a measure of the fraction of distorted morphologies in the AGN and control samples, i.e., quantifying the signature of recent mergers which might potentially be responsible for fueling/triggering the AGN. We find that (1) the vast majority (>85%) of the AGN host galaxies do not show strong distortions and (2) there is no significant difference in the distortion fractions between active and inactive galaxies. Our findings provide the best direct evidence that, since z [?] 1, the bulk of black hole (BH) accretion has not been triggered by major galaxy mergers, therefore arguing that the alternative mechanisms, i.e., internal secular processes and minor interactions, are the leading triggers for the episodes of major BH growth. We also exclude an alternative interpretation of our results: a substantial time lag between merging and the observability of the AGN phase could wash out the most significant merging signatures, explaining the lack of enhancement of strong distortions on the AGN hosts. We show that this alternative scenario is unlikely due to (1) recent major mergers being ruled out for the majority of sources due to the high fraction of disk-hosted AGNs, (2) the lack of a significant X-ray signal in merging inactive galaxies as a signature of a potential buried AGN, and (3) the low levels of soft X-ray obscuration for AGNs hosted by interacting galaxies, in contrast to model predictions.
Published: 2011

232. The properties of Lyα nebulae: gas kinematics from nonresonant lines

Author: Jahnke, Knud [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany)]
Published: 2014
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233. Euclid: Forecasts for k-cut 3×2 Point Statistics

Author: Richard Massey, Knud Jahnke, Harry Teplitz, J. Carretero, R. P. Saglia, Domenico Sapone, I. Lloro, Natalia Auricchio, M. Martinelli, Massimo Brescia, B. Garilli, F. Raison, Carmelita Carbone, Yu Wang, P. Tallada Crespí, Jochen Weller, Stefano Camera, L. Moscardini, S. Kermiche, Leonardo Corcione, Daniele Tavagnacco, B. Gillis, Stein Vidar Hagfors Haugan, B. Morin, Ole Marggraf, C. Giocoli, Edwin A. Valentijn, G. Sirri, I. Tutusaus, Stefano Cavuoti, S. Casas, K. Pedersen, S. Pires, W. A. Holmes, V. Yankelevich, A. Boucaud, V. Capobianco, S. Paltani, L. Conversi, C. Bodendorf, T. Kitching, G. Polenta, L. Popa, R. Cledassou, M. Poncet, T. Vassallo, A. Zacchei, M. Kilbinger, A. Balestra, Andy Taylor, Will J. Percival, E. Branchini, M. Castellano, V. Pettorino, Mauro Roncarelli, Luigi Guzzo, Massimo Meneghetti, Agnès Ferté, F. Bernardeau, E. M. Huff, G. Congedo, A. Secroun, Mark Cropper, K. Markovic, G. Seidel, Ismael Tereno, A. Cimatti, G. Meylan, S. Niemi, Felix Hormuth, F. Sureau, Sebastiano Ligori, Michele Moresco, P. B. Lilje, Simona Mei, Hannu Kurki-Suonio, S. Serrano, V. F. Cardone, Emanuel Rossetti, C. Padilla, A. C. Deshpande, Julien Zoubian, E. Franceschi, Alkistis Pourtsidou, Jason Rhodes, E. Medinaceli, Rafael Toledo-Moreo, Luca Valenziano, Peter Taylor, D. Bonino, Chiara Sirignano, M. Kunz, Z. Sakr, Peter Schneider, Fabio Pasian, Taylor, Peter L., Kitching, T., Cardone, V. F., Ferté, A., Huff, E. M., Bernardeau, F., Rhodes, J., Deshpande, A. C., Tutusaus, I., Pourtsidou, Alkisti, Camera, S., Carbone, C., Casas, S., Martinelli, M., Pettorino, V., Sakr, Z., Sapone, D., Yankelevich, V., Auricchio, N., Balestra, A., Bodendorf, C., Bonino, D., Boucaud, A., Branchini, Enzo, Brescia, M., Capobianco, V., Carretero, J., Castellano, M., Cavuoti, S., Cimatti, A., Cledassou, R., Congedo, G., Conversi, L., Corcione, L., Cropper, Mark, Franceschi, E., Garilli, B., Gillis, B., Giocoli, C., Guzzo, L., Haugan, S. V. H., Holmes, W., Hormuth, F., Jahnke, Knud, Kermiche, S., Kilbinger, M., Kunz, M., Kurki-Suonio, H., Ligori, S., Lilje, Per B., Lloro, I., Marggraf, O., Markovic, K., Massey, R., Mei, S., Medinaceli, E., Meneghetti, M., Meylan, G., Moresco, M., Morin, B., Moscardini, Lauro, Niemi, S., Padilla, C., Pasian, F., Paltani, S., Pedersen, K., Pires, S., Percival, Will J., Polenta, G., Poncet, M., Popa, L., Raison, F., Roncarelli, M., Rossetti, E., Saglia, R., Schneider, Peter, Secroun, A., Seidel, G., Serrano, S., Sirignano, C., Sirri, G., Sureau, F., Crespí, P. Tallada, Tavagnacco, D., Taylor, A. N., Teplitz, H. I., Tereno, I., Toledo-Moreo, R., Valentijn, E. A., Valenziano, L., Vassallo, T., Wang, Yun, Weller, Jochen, Zacchei, A., and Zoubian, J.
Subjects: Physics, Spectral density, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Baryon, Statistics, Dark energy, astro-ph.CO, Matrix analysis, Sensitivity (control systems), Cluster analysis, Weak gravitational lensing, Astrophysics::Galaxy Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Modelling uncertainties at small scales, i.e. high $k$ in the power spectrum $P(k)$, due to baryonic feedback, nonlinear structure growth and the fact that galaxies are biased tracers poses a significant obstacle to fully leverage the constraining power of the {\it Euclid} wide-field survey. $k$-cut cosmic shear has recently been proposed as a method to optimally remove sensitivity to these scales while preserving usable information. In this paper we generalise the $k$-cut cosmic shear formalism to $3 \times 2$ point statistics and estimate the loss of information for different $k$-cuts in a $3 \times 2$ point analysis of the {\it Euclid} data. Extending the Fisher matrix analysis of~\citet{blanchard2019euclid}, we assess the degradation in constraining power for different $k$-cuts. We work in the idealised case and assume the galaxy bias is linear, the covariance is Gaussian, while neglecting uncertainties due to photo-z errors and baryonic feedback. We find that taking a $k$-cut at $2.6 \ h \ {\rm Mpc} ^{-1}$ yields a dark energy Figure of Merit (FOM) of 1018. This is comparable to taking a weak lensing cut at $\ell = 5000$ and a galaxy clustering and galaxy-galaxy lensing cut at $\ell = 3000$ in a traditional $3 \times 2$ point analysis. We also find that the fraction of the observed galaxies used in the photometric clustering part of the analysis is one of the main drivers of the FOM. Removing $50 \% \ (90 \%)$ of the clustering galaxies decreases the FOM by $19 \% \ (62 \%)$. Given that the FOM depends so heavily on the fraction of galaxies used in the clustering analysis, extensive efforts should be made to handle the real-world systematics present when extending the analysis beyond the luminous red galaxy (LRG) sample....
Published: 2021
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234. NISP FM TV3 Test Specifications

Author: FRANCESCHI, ENRICO, ITA, FRA, DEU, Ealet, Anne, Jahnke, Knud, Barbier, Remi, Valenziano, Luca, Dusini, Stefano, Prieto, Eric, and Maciaszek, Thierry
Abstract: This document describes the specifications of the thermal vacuum test called NISP FM TV 3. This test comes after NISP EM and NISP FM TV1/2 tests. NISP FM TV1 test was dedicated to the final characterization of the 16 flight SCS triplet. NISP FM TV2 test was dedicated to first verification of the NISP optical performances and procedure debugging to prepare the NISP FM TV3 performance and calibration test. The NISP FM TV3 is the formal NISP performance and calibration ground test.
Published: 2020

235. Euclid Near Infrared Spectrometer and Photometer instrument concept and first test results obtained for different breadboards models at the end of phase C

Author: S. Ventura, Eric Prieto, Cédric Thizy, Florent Beaumont, Jean-Christophe Salvignol, René J. Laureijs, Warren Holmes, A. N. Sørensen, Carlotta Bonoli, Maurizio Spurio, Augustyn Waczynski, Jérôme Amiaux, J. F. Macías-Pérez, P. Sanchez, G. Sirri, Favio Bortoletto, Francesca Sortino, Giuseppe D. Racca, Natalia Auricchio, Doriane Dormoy, Paolo Strada, Ricard Casas, Corinne Toulouse-Aastrup, David Lizán, Maurizio D'Alessandro, David Le Mignant, C. Rosset, S. Vives, Anne Bonnefoi, L. Stanco, J. Garcia, M. Tenti, Jean-Luc Gimenez, N. Mauri, Frank Grupp, F. Fornari, Rafael Toledo-Moreo, Michael Seiffert, A. Caillat, Felix Hormuth, Allan Hornstrup, Annarita Margiotta, Tony Pamplona, Gian Paolo Guizzo, Leonardo Corcione, Michel Berthé, Riccardo Travaglini, Anne Costille, Niels Christian Jessen, L. Pasqualini, Luca Valenziano, F. Laudisio, L. Patrizii, Gianluca Morgante, Cristobal Padilla, S. Dusini, Philippe Laurent, A. Secroun, Ivan Lloro, Anne Ealet, Thierry Maciaszek, M. Trifoglio, G. Seidel, Yannick Mellier, Ulf E. Israelsson, A. Balestra, Adriano De Rosa, E. Medinaceli, M. Carle, Sylvain Ferriol, Chiara Sirignano, Jaime Gomez, Michael I. Andersen, Knud Jahnke, Christophe Fabron, R. Farinelli, Emmanuel Grassi, F. Giacomini, B. Foulon, Remi Barbier, Jean Christophe Barrière, J. J. Díaz, Mathieu Niclas, P. B. Lilje, Sebastiano Ligori, F. Dal Corso, Peter Viggo Jakobsen, Carlos Colodro-Conde, Franck Ducret, J. C. Clemens, E. Franceschi, Mikel Lamensans, W. Gillard, Tobias Boenke, Tommaso Chiarusi, William Bon, B. Serra, Stefanie Wachter, Laurent Martin, C. Rossin, Aurélien Febvre, E. Borsato, Carolin Wimmer, B. Kubik, Centre National d’Études Spatiales [Paris] (CNES), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), EUCLID, Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), MacEwen, Howard A., G. Fazio, Giovanni, Lystrup, Makenzie, Maciaszek, Thierry, Ealet, Anne, Jahnke, Knud, Prieto, Eric, Barbier, Rémi, Mellier, Yannick, Beaumont, Florent, Bon, William, Bonefoi, Anne, Carle, Michael, Caillat, Amandine, Costille, Anne, Dormoy, Doriane, Ducret, Franck, Fabron, Christophe, Febvre, Aurélien, Foulon, Benjamin, Garcia, Jose, Gimenez, Jean-Luc, Grassi, Emmanuel, Laurent, Philippe, Mignant, David Le, Martin, Laurent, Rossin, Christelle, Pamplona, Tony, Sanchez, Patrice, Vives, Sebastien, Clémens, Jean Claude, Gillard, William, Niclas, Mathieu, Secroun, Aurélia, Serra, Benoit, Kubik, Bogna, Ferriol, Sylvain, Amiaux, Jérome, Barrière, Jean Christophe, Berthe, Michel, Rosset, Cyrille, Macias-Perez, Juan Francisco, Auricchio, Natalia, De Rosa, Adriano, Franceschi, Enrico, Guizzo, Gian Paolo, Morgante, Gianluca, Sortino, Francesca, Trifoglio, Massimo, Valenziano, Luca, Patrizii, Laura, Chiarusi, T., Fornari, F., Giacomini, F., Margiotta, A., Mauri, N., Pasqualini, L., Sirri, G., Spurio, M., Tenti, M., Travaglini, R., Dusini, Stefano, Dal Corso, F., Laudisio, F., Sirignano, C., Stanco, L., Ventura, S., Borsato, Enrico, Bonoli, Carlotta, Bortoletto, Favio, Balestra, Andrea, D'Alessandro, Maurizio, Celi, Eduardo Medina, Farinelli, Ruben, Corcione, Leonardo, Ligori, Sebastiano, Grupp, Frank, Wimmer, Carolin, Hormuth, Felix, Seidel, Gregor, Wachter, Stefanie, Padilla, Cristobal, Lamensans, Mikel, Casas, Ricard, Lloro, Ivan, Toledo-Moreo, Rafael, Gomez, Jaime, Colodro-Conde, Carlo, Lizán, David, Diaz, Jose Javier, Lilje, Per B., Toulouse-Aastrup, Corinne, Andersen, Michael I., Sørensen, Anton N., Jakobsen, Peter, Hornstrup, Allan, Jessen, Niels-Christian, Thizy, Cédric, Holmes, Warren, Israelsson, Ulf, Seiffert, Michael, Waczynski, Augustyn, Laureijs, René J., Racca, Giuseppe, Salvignol, Jean-Christophe, Boenke, Tobia, and Strada, Paolo
Subjects: Cosmic Vision, [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Control unit, Condensed Matter Physic, 01 natural sciences, 7. Clean energy, law.invention, Photometry, 010309 optics, Optics, law, 0103 physical sciences, NISP, Electrical and Electronic Engineering, 010303 astronomy & astrophysics, Spectroscopy, ComputingMilieux_MISCELLANEOUS, Physics, Instrument control, Spacecraft, Spectrometer, business.industry, Electronic, Optical and Magnetic Material, Euclid, Computer Science Applications1707 Computer Vision and Pattern Recognition, Instrument, Photometer, Breadboard, Applied Mathematic, Grism, 13. Climate action, Infrared, business
Abstract: The Euclid mission objective is to understand why the expansion of the Universe is accelerating through by mapping the geometry of the dark Universe by investigating the distance-redshift relationship and tracing the evolution of cosmic structures. The Euclid project is part of ESA's Cosmic Vision program with its launch planned for 2020 (ref [1]). The NISP (Near Infrared Spectrometer and Photometer) is one of the two Euclid instruments and is operating in the near-IR spectral region (900- 2000nm) as a photometer and spectrometer. The instrument is composed of: - a cold (135K) optomechanical subsystem consisting of a Silicon carbide structure, an optical assembly (corrector and camera lens), a filter wheel mechanism, a grism wheel mechanism, a calibration unit and a thermal control system - a detection subsystem based on a mosaic of 16 HAWAII2RG cooled to 95K with their front-end readout electronic cooled to 140K, integrated on a mechanical focal plane structure made with molybdenum and aluminum. The detection subsystem is mounted on the optomechanical subsystem structure - a warm electronic subsystem (280K) composed of a data processing / detector control unit and of an instrument control unit that interfaces with the spacecraft via a 1553 bus for command and control and via Spacewire links for science data This presentation describes the architecture of the instrument at the end of the phase C (Detailed Design Review), the expected performance, the technological key challenges and preliminary test results obtained for different NISP subsystem breadboards and for the NISP Structural and Thermal model (STM). © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only. Copyright (2016) Society of Photo Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.
Published: 2016

236. Mission-level performance verification approach for the Euclid space mission

Author: Roberto Scaramella, Tom Kitching, Marc Sauvage, Anna Gregorio, J. Hoar, René J. Laureijs, Will J. Percival, Christophe Dabin, Guillermo Buenadicha, Stefanie Wachter, Andrea Zacchei, Yun Wang, Jose Lorenzo Alvarez, Bianca Garilli, Jérôme Amiaux, Jean Christophe Salvignol, Gonzalo Saavedra Criado, Ruyman Azzollini, Mark Cropper, Yannick Mellier, Martin Kilbinger, Giuseppe D. Racca, Anne Ealet, Luis M. Gaspar Venancio, Knud Jahnke, Henk Hoekstra, R. Vavrek, Angeli, George Z., Dierickx, Philippe, George Z. Angeli, Philippe Dierickx, Vavrek, Roland D., Laureijs, René J., Lorenzo Alvarez, Jose, Amiaux, Jérôme, Mellier, Yannick, Azzollini, Ruyman, Buenadicha, Guillermo, Saavedra Criado, Gonzalo, Cropper, Mark, Dabin, Christophe, Ealet, Anne, Garilli, Bianca, Gregorio, Anna, Hoekstra, Henk, Jahnke, Knud, Kilbinger, Martin, Kitching, Tom, Hoar, John, Percival, Will, Racca, Giuseppe D., Salvignol, Jean Christophe, Sauvage, Marc, Scaramella, Roberto, Gaspar Venancio, Luis M., Wang, Yun, Zacchei, Andrea, and Wachter, Stefanie
Subjects: Mission Database, Galactic astronomy, Condensed Matter Physic, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, 010309 optics, Telescope, Euclid, parameter database, performance verification, Electronic, Optical and Magnetic Materials, Condensed Matter Physics, Computer Science Applications1707 Computer Vision and Pattern Recognition, Applied Mathematics, Electrical and Electronic Engineering, law, 0103 physical sciences, Electronic, Optical and Magnetic Materials, Aerospace engineering, 010303 astronomy & astrophysics, Weak gravitational lensing, Astrophysics::Galaxy Astrophysics, Photometric redshift, Physics, Spacecraft, Spectrometer, business.industry, Electronic, Optical and Magnetic Material, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Galaxy, Applied Mathematic, Dark energy, Astrophysics::Earth and Planetary Astrophysics, business
Abstract: ESA's Dark Energy Mission Euclid will map the 3D matter distribution in our Universe using two Dark Energy probes: Weak Lensing (WL) and Galaxy Clustering (GC). The extreme accuracy required for both probes can only be achieved by observing from space in order to limit all observational biases in the measurements of the tracer galaxies. Weak Lensing requires an extremely high precision measurement of galaxy shapes realised with the Visual Imager (VIS) as well as photometric redshift measurements using near-infrared photometry provided by the Near Infrared Spectrometer Photometer (NISP). Galaxy Clustering requires accurate redshifts (Δz/(z+1)
Published: 2016

237. ACCRETION RATE AND THE PHYSICAL NATURE OF UNOBSCURED ACTIVE GALAXIES

Author: Anton M. Koekemoer, V. Mainieri, Chris Impey, Yoshiaki Taniguchi, Heng Hao, Francesca Civano, Mara Salvato, C. T. Liu, Nick Scoville, Knud Jahnke, C. Megan Urry, Brandon C. Kelly, Giorgio Lanzuisi, Jonathan R. Trump, Jared M. Gabor, Andrea Merloni, Aleksandar M. Diamond-Stanic, Tohru Nagao, Trump, Jonathan R, Impey, Christopher D., Kelly, Brandon C., Civano, Francesca, Gabor, Jared M., Diamond-Stanic, Aleksandar M., Merloni, Andrea, Urry, C. Megan, Hao, Heng, Jahnke, Knud, Nagao, Tohru, Taniguchi, Yoshi, Koekemoer, Anton M., Lanzuisi, Giorgio, Liu, Charle, Mainieri, Vincenzo, Salvato, Mara, and Scoville, Nick Z.
Subjects: Systematic error, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Active galactic nucleus, 010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Virial theorem, Physical cosmology, Accretion rate, accretion, quasars: general, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, accretion disk, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Nuclear and High Energy Physic, 0105 earth and related environmental sciences, Physics, Astronomy and Astrophysics, Torus, galaxies: Seyfert, Accretion (astrophysics), Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, galaxies: nuclei, quasars: emission line, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We show how accretion rate governs the physical properties of a sample of unobscured broad-line, narrow-line, and lineless active galactic nuclei (AGNs). We avoid the systematic errors plaguing previous studies of AGN accretion rate by using accurate accretion luminosities (L_int) from well-sampled multiwavelength SEDs from the Cosmic Evolution Survey (COSMOS), and accurate black hole masses derived from virial scaling relations (for broad-line AGNs) or host-AGN relations (for narrow-line and lineless AGNs). In general, broad emission lines are present only at the highest accretion rates (L_int/L_Edd > 0.01), and these rapidly accreting AGNs are observed as broad-line AGNs or possibly as obscured narrow-line AGNs. Narrow-line and lineless AGNs at lower specific accretion rates (L_int/L_Edd < 0.01) are unobscured and yet lack a broad line region. The disappearance of the broad emission lines is caused by an expanding radiatively inefficient accretion flow (RIAF) at the inner radius of the accretion disk. The presence of the RIAF also drives L_int/L_Edd < 10^-2 narrow-line and lineless AGNs to 10 times higher ratios of radio to optical/UV emission than L_int/L_Edd > 0.01 broad-line AGNs, since the unbound nature of the RIAF means it is easier to form a radio outflow. The IR torus signature also tends to become weaker or disappear from L_int/L_Edd < 0.01 AGNs, although there may be additional mid-IR synchrotron emission associated with the RIAF. Together these results suggest that specific accretion rate is an important physical "axis" of AGN unification, described by a simple model., Accepted for publication in the Astrophysical Journal. 15 pages, 9 figures
Published: 2011

238. Astronomy's climate emissions: Global travel to scientific meetings in 2019.

Author: Gokus A, Jahnke K, Woods PM, Moss VA, Ossenkopf-Okada V, Sacchi E, Stevens ARH, Burtscher L, Kayhan C, Dalgleish H, Grinberg V, Rector TA, Rybizki J, and White J
Abstract: Travel to academic conferences-where international flights are the norm-is responsible for a sizeable fraction of the greenhouse gas (GHG) emissions associated with academic work. In order to provide a benchmark for comparison with other fields, as well as for future reduction strategies and assessments, we estimate the CO 2 -equivalent emissions for conference travel in the field of astronomy for the prepandemic year 2019. The GHG emission of the international astronomical community's 362 conferences and schools in 2019 amounted to 42,500 tCO 2 e, assuming a radiative-forcing index factor of 1.95 for air travel. This equates to an average of 1.0 ± 0.6 tCO 2 e per participant per meeting. The total travel distance adds up to roughly 1.5 Astronomical Units, that is, 1.5 times the distance between the Earth and the Sun. We present scenarios for the reduction of this value, for instance with virtual conferencing or hub models, while still prioritizing the benefits conferences bring to the scientific community., (© The Author(s) 2024. Published by Oxford University Press on behalf of National Academy of Sciences.)
Published: 2024
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239. Detection of stellar light from quasar host galaxies at redshifts above 6.

Author: Ding X, Onoue M, Silverman JD, Matsuoka Y, Izumi T, Strauss MA, Jahnke K, Phillips CL, Li J, Volonteri M, Haiman Z, Andika IT, Aoki K, Baba S, Bieri R, Bosman SEI, Bottrell C, Eilers AC, Fujimoto S, Habouzit M, Imanishi M, Inayoshi K, Iwasawa K, Kashikawa N, Kawaguchi T, Kohno K, Lee CH, Lupi A, Lyu J, Nagao T, Overzier R, Schindler JT, Schramm M, Shimasaku K, Toba Y, Trakhtenbrot B, Trebitsch M, Treu T, Umehata H, Venemans BP, Vestergaard M, Walter F, Wang F, and Yang J
Abstract: The detection of starlight from the host galaxies of quasars during the reionization epoch (z > 6) has been elusive, even with deep Hubble Space Telescope observations 1,2 . The current highest redshift quasar host detected 3 , at z = 4.5, required the magnifying effect of a foreground lensing galaxy. Low-luminosity quasars 4-6 from the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) 7 mitigate the challenge of detecting their underlying, previously undetected host galaxies. Here we report rest-frame optical images and spectroscopy of two HSC-SSP quasars at z > 6 with the JWST. Using near-infrared camera imaging at 3.6 and 1.5 μm and subtracting the light from the unresolved quasars, we find that the host galaxies are massive (stellar masses of 13 × and 3.4 × 10 10 M ☉ , respectively), compact and disc-like. Near-infrared spectroscopy at medium resolution shows stellar absorption lines in the more massive quasar, confirming the detection of the host. Velocity-broadened gas in the vicinity of these quasars enables measurements of their black hole masses (1.4 × 10 9 and 2.0 × 10 8 M ☉ , respectively). Their location in the black hole mass-stellar mass plane is consistent with the distribution at low redshift, suggesting that the relation between black holes and their host galaxies was already in place less than a billion years after the Big Bang., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)
Published: 2023
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240. Cosmology and fundamental physics with the Euclid satellite.

Author: Amendola L, Appleby S, Avgoustidis A, Bacon D, Baker T, Baldi M, Bartolo N, Blanchard A, Bonvin C, Borgani S, Branchini E, Burrage C, Camera S, Carbone C, Casarini L, Cropper M, de Rham C, Dietrich JP, Di Porto C, Durrer R, Ealet A, Ferreira PG, Finelli F, García-Bellido J, Giannantonio T, Guzzo L, Heavens A, Heisenberg L, Heymans C, Hoekstra H, Hollenstein L, Holmes R, Hwang Z, Jahnke K, Kitching TD, Koivisto T, Kunz M, La Vacca G, Linder E, March M, Marra V, Martins C, Majerotto E, Markovic D, Marsh D, Marulli F, Massey R, Mellier Y, Montanari F, Mota DF, Nunes NJ, Percival W, Pettorino V, Porciani C, Quercellini C, Read J, Rinaldi M, Sapone D, Sawicki I, Scaramella R, Skordis C, Simpson F, Taylor A, Thomas S, Trotta R, Verde L, Vernizzi F, Vollmer A, Wang Y, Weller J, and Zlosnik T
Abstract: Euclid is a European Space Agency medium-class mission selected for launch in 2020 within the cosmic vision 2015-2025 program. The main goal of Euclid is to understand the origin of the accelerated expansion of the universe. Euclid will explore the expansion history of the universe and the evolution of cosmic structures by measuring shapes and red-shifts of galaxies as well as the distribution of clusters of galaxies over a large fraction of the sky. Although the main driver for Euclid is the nature of dark energy, Euclid science covers a vast range of topics, from cosmology to galaxy evolution to planetary research. In this review we focus on cosmology and fundamental physics, with a strong emphasis on science beyond the current standard models. We discuss five broad topics: dark energy and modified gravity, dark matter, initial conditions, basic assumptions and questions of methodology in the data analysis. This review has been planned and carried out within Euclid's Theory Working Group and is meant to provide a guide to the scientific themes that will underlie the activity of the group during the preparation of the Euclid mission.
Published: 2018
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