398 results on '"Windhorst, R. A."'
Search Results
102. Closing in on the Hydrogen Reionization Edge at z < 7.2 with Deep STIS/CCD Parallels
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Windhorst, R., Bernstein, R., Collins, N., Plait, P., Woodgate, B., Mather, J., Madau, P., Shaver, P., Cristiani, Stefano, editor, Renzini, Alvio, editor, and Williams, Robert E., editor
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- 2001
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103. Young and Old Galaxies at High Redshift
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Windhorst, R., Odewahn, S., Burg, C., Cohen, S., Waddington, I., Block, David L., editor, Puerari, Ivânio, editor, Stockton, Alan, editor, and Ferreira, Dewet, editor
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- 2000
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104. JWST's PEARLS: A new lens model for ACT-CL J0102-4915, "El Gordo," and the first red supergiant star at cosmological distances discovered by JWST.
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Diego, J. M., Meena, A. K., Adams, N. J., Broadhurst, T., Dai, L., Coe, D., Frye, B., Kelly, P., Koekemoer, A. M., Pascale, M., Willner, S. P., Zackrisson, E., Zitrin, A., Windhorst, R. A., Cohen, S. H., Jansen, R. A., Summers, J., Tompkins, S., Conselice, C. J., and Driver, S. P.
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COSMOLOGICAL distances ,STELLAR parallax ,SUPERGIANT stars ,SPACE telescopes ,DWARF galaxies ,GALACTIC redshift - Abstract
The first James Webb Space Telescope (JWST) data on the massive colliding cluster El Gordo allow for 23 known families of multiply lensed images to be confirmed and for eight new members of these families to be identified. Based on these families, which have been confirmed spectroscopically by MUSE, we derived an initial lens model. This model guided the identification of 37 additional families of multiply lensed galaxies, among which 28 are entirely new systems, and nine were previously known. The initial lens model determined geometric redshifts for the 37 new systems. The geometric redshifts agree reasonably well with spectroscopic or photometric redshifts when those are available. The geometric redshifts enable two additional models that include all 60 families of multiply lensed galaxies spanning a redshift range 2 < z < 6. The derived dark-matter distribution confirms the double-peak configuration of mass found by earlier work with the southern and northern clumps having similar masses. We confirm that El Gordo is the most massive known cluster at z > 0:8 and has an estimated virial mass close the maximum mass allowed by standard cosmological models. The JWST images also reveal the presence of small-mass perturbers that produce small lensing distortions. The smallest of these is consistent with being a dwarf galaxy at z = 0:87 and has an estimated mass of 3:8 109 M, making it the smallest substructure found at z > 0:5. The JWST images also show several candidate caustic-crossing events. One of them is detected at high significance at the expected position of the critical curve and is likely a red supergiant star at z = 2:1878. This would be the first red supergiant found at cosmological distances. The cluster lensing should magnify background objects at z > 6, making more of them visible than in blank fields of a similar size, but there appears to be a deficiency of such objects. [ABSTRACT FROM AUTHOR]
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- 2023
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105. The HST Medium Deep Susrvey: Galaxy Morphology at High Redshift
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Griffiths, R. E., Ratnatunga, K. U., Casertano, S., Im, M., Neuschaefer, L. W., Ellis, R. S., Gilmore, G. F., Elson, R. A. W., Glazebrook, K., Santiago, B., Windhorst, R. A., Driver, S. P., Ostrander, E. J., Mutz, S. B., Koo, D. C., Illingworth, G. D., Forbes, D. A., Phillips, A. C., Green, R. F., Huchra, J. P., Tyson, A. J., Kafatos, Menas, editor, and Kondo, Yoji, editor
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- 1996
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106. The nature of faint galaxies from the medium deep survey and other deep HST images
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Windhorst, R. A., Driver, S. P., Ostrander, E. J., Mutz, S. B., Schmidtke, P. C., Griffiths, R. E., Ratnatunga, K. U., Casertano, S., Im, M., Neuschaefer, L. W., Ellis, R. S., Gilmore, G. F., Elson, R. A. W., Glazebrook, K., Santiago, B., Keel, W. C., Koo, D. C., Illingworth, G. D., Forbes, D. A., Phillips, A. C., Green, R. F., Huchra, J. P., Tyson, A. J., Araki, H., editor, Brézin, E., editor, Ehlers, J., editor, Frisch, U., editor, Hepp, K., editor, Jaffe, R. L., editor, Kippenhahn, R., editor, Weidenmüller, H. A., editor, Wess, J., editor, Zittartz, J., editor, Beiglböck, W., editor, Hippelein, Hans, editor, Meisenheimer, Klaus, editor, and Röser, Hermann-Josef, editor
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- 1995
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107. The NuSTAR extragalactic survey of the James Webb Space Telescope North Ecliptic Pole time-domain field
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Zhao, X, primary, Civano, F, additional, Fornasini, F M, additional, Alexander, D M, additional, Cappelluti, N, additional, Chen, C T, additional, Cohen, S H, additional, Elvis, M, additional, Gandhi, P, additional, Grogin, N A, additional, Hickox, R C, additional, Jansen, R A, additional, Koekemoer, A, additional, Lanzuisi, G, additional, Maksym, W P, additional, Masini, A, additional, Rosario, D J, additional, Ward, M J, additional, Willmer, C N A, additional, and Windhorst, R A, additional
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- 2021
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108. HST/FOS UV-Spectroscopy of Weak Radio Galaxies At z = 0.1-0.6
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Windhorst, R. A., Pascarelle, S. M., Keel, W. C., Bertola, F., McCarthy, P. J., O’Connell, R. W., Renzini, A., Spinrad, H., Wamsteker, W., editor, Longair, M. S., editor, and Kondo, Y., editor
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- 1994
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109. Deep Extragalactic VIsible Legacy Survey (DEVILS): consistent multiwavelength photometry for the DEVILS regions (COSMOS, XMMLSS, and ECDFS)
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Davies, L J M, primary, Thorne, J E, additional, Robotham, A S G, additional, Bellstedt, S, additional, Driver, S P, additional, Adams, N J, additional, Bilicki, M, additional, Bowler, R A A, additional, Bravo, M, additional, Cortese, L, additional, Foster, C, additional, Grootes, M W, additional, Häußler, B, additional, Hashemizadeh, A, additional, Holwerda, B W, additional, Hurley, P, additional, Jarvis, M J, additional, Lidman, C, additional, Maddox, N, additional, Meyer, M, additional, Paolillo, M, additional, Phillipps, S, additional, Radovich, M, additional, Siudek, M, additional, Vaccari, M, additional, and Windhorst, R A, additional
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- 2021
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110. An HR Diagram for the LMC From the Medium Deep Survey
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Forbes, Duncan A., Elson, Rebecca A. W., Griffiths, R. E., Ellis, R. S., Gilmore, G., Green, R. F., Huchra, J. P., Illingworth, G. D., Koo, D. C., Ratnatunga, k., Tyson, A., Windhorst, R. A., Robertson, J. G., editor, and Tango, W. J., editor
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- 1994
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111. The Medium-Deep Survey Using the Hubble Space Telescope
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Griffiths, R. E., Ratnatunga, K., Neuschaefer, L. W., Windhorst, R. A., Gordon, J., Schmidtke, P., Ellis, R. S., Gilmore, G. F., Elson, R. A. W., Schade, D. J., Koo, D. C., Illingworth, G. D., Forbes, D., Phillips, D., Huchra, J. P., Tyson, A. J., Green, R. F., Wamsteker, W., editor, Longair, M. S., editor, and Kondo, Y., editor
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- 1994
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112. Multiband Photometry of Selected Areas in a Study of Galactic Structure
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Lu P. K., Tsay W. S., Chen A. B. C., Chen R., Sun W. H., Byun Υ. I., Chen W. P., Chiueh T. H., Kuo H. J., Burstein D., Hester J. J., Windhorst R. A., Fang L. Z., Chen J. S., Zhu J., Deng L. C., Fan X. H., Jiang Z. J., Li Y., Wu H., Zhang M., Zheng Ζ. Y., Zhou X., Chen F. Z., Deng Z. G., Chu Y. Q., Su J., Shang Ζ. H., Yan Η. J., and Xia X. Y.
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Astronomy ,QB1-991 - Published
- 1997
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113. Free-form Lens Model and Mass Estimation of the High-redshift Galaxy Cluster ACT-CL J0102-4915, “El Gordo”
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Diego, Jose M., primary, Molnar, S. M., additional, Cerny, C., additional, Broadhurst, T., additional, Windhorst, R., additional, Zitrin, A., additional, Bouwens, R., additional, Coe, D., additional, Conselice, C., additional, and Sharon, K., additional
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- 2020
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114. What Will the Next Generation Radio Telescope Detect at 1.4 GHz?
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Hopkins, A., Windhorst, R., Cram, L., and Ekers, R.
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- 2000
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115. Young and Old Galaxies at High Redshift
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Windhorst, R., Odewahn, S., Burg, C., Cohen, S., and Waddington, I.
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- 1999
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116. Limits to Rest-frame Ultraviolet Emission from Far-infrared-luminous z ≃ 6 Quasar Hosts
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Marshall, M. A., primary, Mechtley, M., additional, Windhorst, R. A., additional, Cohen, S. H., additional, Jansen, R. A., additional, Jiang, L., additional, Jones, V. R., additional, Wyithe, J. S. B., additional, Fan, X., additional, Hathi, N. P., additional, Jahnke, K., additional, Keel, W. C., additional, Koekemoer, A. M., additional, Marian, V., additional, Ren, K., additional, Robinson, J., additional, Röttgering, H. J. A., additional, Ryan, R. E., additional, Scannapieco, E., additional, Schneider, D. P., additional, Schneider, G., additional, Smith, B. M., additional, and Yan, H., additional
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- 2020
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117. The Insignificance of Major Mergers in Driving Star Formation at z approximately equal to 2
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Kaviraj, S, Cohen, S, Windhorst, R. A, Silk, J, O'Connell, R. W, Dopita, M. A, Dekel, A, Hathi, N. P, Straughn, A, and Rutkowski, M
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Astrophysics - Abstract
We study the significance of major mergers in driving star formation in the early Universe, by quantifying the contribution of this process to the total star formation budget in 80 massive (M(*) > 10(exp 10) Solar M) galaxies at z approx = 2. Employing visually-classified morphologies from rest-frame V-band HST imaging, we find that 55(exp +/-14)% of the star formation budget is hosted by non-interacting late-types, with 27(exp +/-18% in major mergers and 18(exp +/- 6)% in spheroids. Given that a system undergoing a major merger continues to experience star formation driven by other processes at this epoch (e.g. cold accretion, minor mergers), approx 27% is a likely upper limit for the major-merger contribution to star formation activity at this epoch. The ratio of the average specific star formation rate in major mergers to that in the non-interacting late-types is approx 2.2:1, suggesting that the typical enhancement of star formation due to major merging is modest and that just under half the star formation in systems experiencing major mergers is unrelated to the merger itself. Taking this into account, we estimate that the actual major-merger contribution to the star formation budget may be as low as approx 15%. While our study does not preclude a major-merger-dominated. era in the very early Universe, if the major-merger contribution to star formation does not evolve significantly into larger look-back times, then this process has a relatively insignificant role in driving stellar mass assembly over cosmic time.
- Published
- 2012
118. The Size Evolution of Passive Galaxies: Observations From the Wide-Field Camera 3 Early Release Science Program
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Ryan, R. E., Jr, Mccarthy, P.J, Cohen, S. H, Yan, H, Hathi, N. P, Koekemoer, A. M, Rutkowski, M. J, Mechtley, M. R, Windhorst, R. A, O’Connell, R. W, Balick, B, Bond, H. E, Bushouse, H, Calzetti, D, Crockett, R. M, Disney, M, Dopita, M. A, Frogel, J. A, Hall, D., N., B, Holtzman, J. A, Kaviraj, S, Kimble, R. A, MacKenty, J, Trauger, J, and Young, E
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Astrophysics - Abstract
We present the size evolution of passively evolving galaxies at z approximately 2 identified in Wide-Field Camera 3 imaging from the Early Release Science program. Our sample was constructed using an analog to the passive BzK galaxy selection criterion, which isolates galaxies with little or no ongoing star formation at z greater than approximately 1.5. We identify 30 galaxies in approximately 40 arcmin(sup 2) to H less than 25 mag. By fitting the 10-band Hubble Space Telescope photometry from 0.22 micrometers less than approximately lambda (sub obs) 1.6 micrometers with stellar population synthesis models, we simultaneously determine photometric redshift, stellar mass, and a bevy of other population parameters. Based on the six galaxies with published spectroscopic redshifts, we estimate a typical redshift uncertainty of approximately 0.033(1+z).We determine effective radii from Sersic profile fits to the H-band image using an empirical point-spread function. By supplementing our data with published samples, we propose a mass-dependent size evolution model for passively evolving galaxies, where the most massive galaxies (M(sub ∗) approximately 10(sup 11) solar mass) undergo the strongest evolution from z approximately 2 to the present. Parameterizing the size evolution as (1 + z)(sup - alpha), we find a tentative scaling of alpha approximately equals (−0.6 plus or minus 0.7) + (0.9 plus or minus 0.4) log(M(sub ∗)/10(sup 9 solar mass), where the relatively large uncertainties reflect the poor sampling in stellar mass due to the low numbers of highredshift systems. We discuss the implications of this result for the redshift evolution of the M(sub ∗)-R(sub e) relation for red galaxies.
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- 2012
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119. Stellar Populations of Lyman Break Galaxies at z approx. to 1-3 in the HST/WFC3 Early Release Science Observations
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Hathi, N. P, Cohen, S. H, Ryan, R. E., Jr, Finkelstein, S. L, McCarthy, P. J, Windhorst, R. A, Yan, H, Koekemoer, A. M, Rutkowski, M. J, OConnell, R. W, Straughn, A. N, Balick, B, Bond, H. E, Calzetti, D, Disney, M. J, Dopita, M. A, Frogel, Jay A, Hall, D. N. B, Holtzman, J. A, Kimble, R. A, Paresce, F, Saha, A, Silk, J. I, Tauger, J. T, and Young, E. T
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Astronomy - Abstract
We analyze the spectral energy distributions (SEDs) of Lyman break galaxies . (LBGs) at z approx = 1-3 selected using the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) UVIS channel filters. These HST /WFC3 obse,rvations cover about 50 arcmin2 in the GOODS-South field as a part of the WFC3 Early Release Science program. These LBGs at z approx = 1-3 are selected using dropout selection criteria similar to high redshift LBGs. The deep multi-band photometry in this field is used to identify best-fit SED models, from which we infer the following results: (1) the photometric redshift estimate of these dropout selected LBGs is accurate to within few percent; (2) the UV spectral slope f3 is redder than at high redshift (z > 3), where LBGs are less dusty; (3) on average, LBGs at .z approx = 1-3 are massive, dustier and more highly star-forming, compared to LBGs at higher redshifts with similar luminosities, though their median values are similar within 1a uncertainties. This could imply that identical dropout selection technique, at all. redshifts, find physically similar galaxies; and (4) the stellar masses of these LBGs are directly proportional to their UV luminosities with a logarithmic slope of approx 0.46, and star-formation rates are proportional to their stellar masses with a logarithmic slope of approx 0.90. These relations hold true - within luminosities probed in this study - for LBGs from z approx = 1.5 to 5. The star-forming galaxies selected using other color-based techniques show similar correlations at z approx = 2, but to avoid any selection biases, and for direct comparison with LBGs at z > 3, a true Lyman break selection at z approx = 2 is essential. The future HST UV surveys,. both wider and deeper, covering a large luminosity range are important to better understand LBG properties, and their evolution.
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- 2012
120. HST WFC3 Early Release Science: Emission-Line Galaxies from IR Grism Observations
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Straughn, A. N, Kuntschner, H, Kuemmel, M, Walsh, J. R, Cohen, S. H, Gardner, J. P, Windhorst, R. A, O'Connell, R. W, Pirzkal, N, Meurer, G, McCarthy, P. J, Hathi, N. P, Malhotra, S, Rhoads, J, Balick, B, Bond, H. E, Calzetti, D, Disney, M. J, Dopita, M. A, Frogel, J. A, Hall, D. N. B, Holtzman, J. A, Kimlbe, R. A, Trauger, J. T, and Young, E. T
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Astronomy - Abstract
We present grism spectra of emission line galaxies (ELGs) from 0.6-1.6 microns from the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). These new infrared grism data augment previous optical Advanced Camera for Surveys G800L (0.6-0.95 micron) grism data in GOODS South, extending the wavelength coverage well past the G800L red cutoff. The ERS grism field was observed at a depth of 2 orbits per grism, yielding spectra of hundreds of faint objects, a subset of which are presented here. ELGs are studied via the Ha, [O III ], and [OII] emission lines detected in the redshift ranges 0.2 less than or equal to z less than or equal to 1.6, 1.2 less than or equal to z less than or equal to 2.4 and 2.0 less than or equal to z less than or equal to 3.6 respectively in the G102 (0.8-1.1 microns; R approximately 210) and C141 (1.1-1.6 microns; R approximately 130) grisms. The higher spectral resolution afforded by the WFC3 grisms also reveals emission lines not detectable with the G800L grism (e.g., [S II] and [S III] lines). From these relatively shallow observations, line luminosities, star formation rates, and grism spectroscopic redshifts are determined for a total of 25 ELGs to M(sub AB)(F098M) approximately 25 mag. The faintest source in our sample with a strong but unidentified emission line--is MAB(F098M)=26.9 mag. We also detect the expected trend of lower specific star formation rates for the highest mass galaxies in the sample, indicative of downsizing and discovered previously from large surveys. These results demonstrate the remarkable efficiency and capability of the WFC3 NIR grisms for measuring galaxy properties to faint magnitudes.
- Published
- 2010
121. Electromagnetic probes of primordial black holes as dark matter
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Kashlinsky, A., Ali-Haimoud, Y., Clesse, S., Garcia-Bellido, J., Wyrzykowski, L., Achucarro, A., Amendola, L., Annis, J., Arbey, A., Arendt, R. G., Atriobarandela, F., Bellomo, N., Belotsky, K., Bernal, J-L, Bird, S., Bozza, V., Byrnes, C., Calchi Novati, S., Calore, F., Carr, B. J., Chluba, J., Cholis, I., Cieplak, A., Cole, P., Dalianis, I., Davis, A-C, Davis, T., Luca, V., Dvorkin, I., Emparan, R., Ezquiaga, J-M, Fleury, P., Franciolini, G., Gaggero, D., Georg, J., Germani, C., Giudice, G-F, Goobar, A., Hasinger, G., Hector, A., Hundertmark, M., Hutsi, G., Jansen, R., Kamionkowski, M., Kawasaki, M., Kazanas, D., Kehagias, A., Khlopov, M., Knebe, A., Kohri, K., Koushiappas, S., Kovetz, E., Kuhnel, F., Macgibbon, J., Marzola, L., Mediavilla, E., Meszaros, P., Mroz, P., Munoz, J., Musco, I., Nesseris, S., Ozsoy, O., Pani, P., Poulin, V., Raccanelli, A., Racco, D., Raidal, M., Ranc, C., Rattenbury, N., Rhodes, J., Ricotti, M., Riotto, A., Rubin, S., Rubio, J., Ruiz-Morales, E., Sasaki, M., Schnittman, J., Shvartzvald, Y., Street, R., Takada, M., Takhistov, V., Tashiro, H., Tasinato, G., Tringas, G., Caner Unal, Tada, Y., Tsapras, Y., Vaskonen, V., Veermae, H., Vidotto, F., Watson, S., Windhorst, R., Yokoyama, S., Young, S., Université Claude Bernard Lyon 1 (UCBL), Université de Lyon, Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon (IPNL), 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), and Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
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Astrophysics and Astronomy ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,lens ,Astrophysics::High Energy Astrophysical Phenomena ,spin: 0 ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,dark matter: density ,galaxy: halo ,star ,accretion ,supernova ,quasar ,LIGO ,Astrophysics::Galaxy Astrophysics ,pulsar ,fluctuation ,Astrophysics::Instrumentation and Methods for Astrophysics ,stability ,coherence ,electromagnetic ,X-ray: background ,infrared ,astro-ph.CO ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,black hole: primordial ,Astrophysics - Cosmology and Nongalactic Astrophysics ,cosmic background radiation: anisotropy - Abstract
The LIGO discoveries have rekindled suggestions that primordial black holes (BHs) may constitute part to all of the dark matter (DM) in the Universe. Such suggestions came from 1) the observed merger rate of the BHs, 2) their unusual masses, 3) their low/zero spins, and 4) also from the independently uncovered cosmic infrared background (CIB) fluctuations signal of high amplitude and coherence with unresolved cosmic X-ray background (CXB). Here we summarize the prospects to resolve this important issue with electromagnetic observations using the instruments and tools expected in the 2020's. These prospects appear promising to make significant, and potentially critical, advances. We demonstrate that in the next decade, new space- and ground-borne electromagnetic instruments, combined with concurrent theoretical efforts, should shed critical light on the long-considered link between primordial BHs and DM. Specifically the new data and methodologies under this program will involve: I) Probing with high precision the spatial spectrum of source-subtracted CIB with Euclid and WFIRST, and its coherence with unresolved cosmic X-ray background using eROSITA and Athena, II) Advanced searches for microlensing of Galactic stars by the intervening Galactic Halo BHs with OGLE, Gaia, LSST and WFIRST, III) Supernovae (SNe) lensing in the upcoming surveys with WFIRST, LSST and also potentially with Euclid and JWST, IV) Advanced theoretical work to understand the details of PBH accretion and evolution and their influence on cosmic microwave background (CMB) anisotropies in light of the next generation CMB experiments, V) Better new samples and theoretical understanding involving stability and properties of ultra faint dwarf galaxies, pulsar timing, and cosmological quasar lensing., Comment: Science whitepaper submitted to the Astro2020 Decadal Survey
- Published
- 2019
122. Major Mergers Are Not the Dominant Trigger for High-accretion AGNs at z ∼ 2
- Author
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Marian, V., Jahnke, K., Mechtley, M., Cohen, S., Husemann, B., Jones, V., Koekemoer, A., Schulze, A., van der Wel, A., Villforth, C., and Windhorst, R.
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Astrophysics::High Energy Astrophysical Phenomena ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
Research over the past decade has shown diminishing evidence for major galaxy mergers being a dominant mechanism for the growth of supermassive black holes (BHs) in galaxies and the triggering of optically or X-ray- selected active galactic nuclei (AGNs). For the first time we test whether such a connection exists at least in the most “plausible” part of parameter space: the highest specific accretion rate broad-line AGNs at the peak epoch of BH activity around z = 2. To that end we analyze two samples—21 AGNs with L/L edd > 0.7 and 92 stellar mass- and redshift-matched inactive galaxies—observed with HST/WFC3. We remove the AGN point sources from their host galaxies and avoid bias in visual classification by adding and then subtracting mock point sources to and from the comparison galaxies, producing matched residual structures for both sets. The resulting samples are joined and visually ranked according to distortion strength by 10 experts. The ensuing individual rankings are combined into a consensus sequence and from this we derive the merger fractions for both samples. With the merger fractions f m,agn = 0.24 ± 0.09 for the AGN host galaxy sample and f m,ina = 0.19 ± 0.04 for the inactive galaxies, we find no significant difference between the samples. This finding is consistent with previous studies for different AGN populations, and we conclude that even BH growth at the highest specific accretion rates and at the peak of cosmic AGN activity is not predominantly caused by major mergers.
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- 2019
123. High-Redshift Milli-Jansky Radio Galaxies
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Dunlop, J., Peacock, J., Windhorst, R., Spinrad, H., Dey, A., Waddington, I., Ekers, R., editor, Fanti, C., editor, and Padrielli, L., editor
- Published
- 1996
- Full Text
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124. X-Ray Properties of Lyman Break Galaxies in the Hubble Deep Field North Region
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Nandra, K, Mushotzky, R. F, Arnaud, K, Steidel, C. C, Adelberger, K. L, Gardner, J. P, Teplitz, H. I, Windhorst, R. A, and White, Nicholas E
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Astrophysics - Abstract
We describe the X-ray properties of a large sample of z approximately 3 Lyman Break Galaxies (LBGs) in the region of the Hubble Deep Field North, derived from the 1 Ms public Chandra observation. Of our sample of 148 LBGs, four are detected individually. This immediately gives a measure of the bright AGN (active galactic nuclei) fraction in these galaxies of approximately 3 per cent, which is in agreement with that derived from the UV (ultraviolet) spectra. The X-ray color of the detected sources indicates that they are probably moderately obscured. Stacking of the remainder shows a significant detection (6 sigma) with an average luminosity of 3.5 x 10(exp 41) erg/s per galaxy in the rest frame 2-10 keV band. We have also studied a comparison sample of 95 z approximately 1 "Balmer Break" galaxies. Eight of these are detected directly, with at least two clear AGN based on their high X-ray luminosity and very hard X-ray spectra respectively. The remainder are of relatively low luminosity (< 10(exp 42) erg/s, and the X-rays could arise from either AGN or rapid star-formation. The X-ray colors and evidence from other wavebands favor the latter interpretation. Excluding the clear AGN, we deduce a mean X-ray luminosity of 6.6 x 10(exp 40) erg/s, a factor approximately 5 lower than the LBGs. The average ratio of the UV and X-ray luminosities of these star forming galaxies L(sub UV)/L (sub X), however, is approximately the same at z = 1 as it is at z = 3. This scaling implies that the X-ray emission follows the current star formation rate, as measured by the UV luminosity. We use our results to constrain the star formation rate at z approximately 3 from an X-ray perspective. Assuming the locally established correlation between X-ray and far-IR (infrared) luminosity, the average inferred star formation rate in each Lyman break galaxy is found to be approximately 60 solar mass/yr, in excellent agreement with the extinction-corrected UV estimates. This provides an external check on the UV estimates of the star formation rates, and on the use of X-ray luminosities to infer these rates in rapidly starforming galaxies at high redshift.
- Published
- 2002
125. The nature of faint galaxies from the medium deep survey and other deep HST images
- Author
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Windhorst, R. A., primary, Driver, S. P., additional, Ostrander, E. J., additional, Mutz, S. B., additional, Schmidtke, P. C., additional, Griffiths, R. E., additional, Ratnatunga, K. U., additional, Casertano, S., additional, Im, M., additional, Neuschaefer, L. W., additional, Ellis, R. S., additional, Gilmore, G. F., additional, Elson, R. A. W., additional, Glazebrook, K., additional, Santiago, B., additional, Keel, W. C., additional, Koo, D. C., additional, Illingworth, G. D., additional, Forbes, D. A., additional, Phillips, A. C., additional, Green, R. F., additional, Huchra, J. P., additional, and Tyson, A. J., additional
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- 1995
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126. A Scheduling Algorithm Compatible with a Distributed Management of Arrivals in the National Airspace System
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Sadovsky, A., primary and Windhorst, R., additional
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- 2019
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- View/download PDF
127. Modelling and Simulating Airport Surface Operations with Gate Conflicts
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Zelinski, S., primary and Windhorst, R., additional
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- 2018
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- View/download PDF
128. Sub-galactic clumps at a redshift of 2.39 and implications for galaxy formation
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Pascarelle, S. M., Windhorst, R. A., Keel, W. C., and Odewahn, S. C.
- Published
- 1996
129. Identification of faint radio sources with optically luminous interacting disk galaxies
- Author
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Windhorst, R. A., Fomalont, E. B., Kellermann, K. I., Partridge, R. B., Richards, E., Franklin, B. E., Pascarelle, S. M., and Griffiths, R. E.
- Published
- 1995
130. Deep HST imaging of distant weak radio and field galaxies
- Author
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Windhorst, R. A, Gordon, J. M, Pascarelle, S. M, Schmidtke, P. C, Keel, W. C, Burkey, J. M, and Dunlop, J. S
- Subjects
Astronomy - Abstract
We present deep Hubble Space Telescope (HST) Wide-Field Camera (WFC) V- and I-band images of three distant weak radio galaxies with z = 0.311-2.390 and seven field galaxies with z = 0.131-0.58. The images were deconvolved with both the Lucy and multiresolution CLEAN methods, which yield a restoring Full Width at Half Maximum (FWHM) of less than or equal to 0.2 sec, (nearly) preserve photons and signal-to-noise ratio at low spatial frequencies, and produce consistent light profiles down to our 2 sigma surface brightness sensitivity limit of V approximately 27.2 and I approximately 25.9 mag/sq arcsec. Multi-component image modeling was used to provide deconvolution-independent estimates of structural parameters for symmetric galaxies. We present 12-band (m(sub 2750) UBVRIgriJHK) photometry for a subset of the galaxies and bootstrap the unknown FOC/48 zero point at 2750 A in three independent ways (yielding m(sub 2750) = 21.34 +/- 0.09 mag for 1.0 e(-)/s). Two radio galaxies with z = 0.311 and 0.528, as well as one field galaxy with z = 0.58, have the colors and spectra of early-type galaxies, and a(exp 1/4)-like light profiles in the HST images. The two at z greater than 0.5 have little or no color gradients in V - I and are likely giant ellipticals, while the z = 0.311 radio galaxy has a dim exponential disk and is likely an S0. Six of the seven field galaxies have light profiles that indicate (small) inner bulges following a(exp 1/4) laws and outer exponential disks, both with little or no color gradients. These are (early-type) spiral galaxies with z = 0.131-0.528. About half have faint companions or bars. One shows lumpy structure, possibly a merger. The compact narrow-line galaxy 53W002 at z = 2.390 has less than or = 30% +/- 10% of its HST V and I flux in the central kiloparsec (due to its weak Active Galactic Nucleus (AGN)). Most of its light (V approximately equal to 23.3) occurs in a symmetric envelope with a regular a(exp 1/4)-like profile of effective radius a approximately equal to 1.1 sec (approximately equal to 12 kpc for H(sub 0) = 50, q(sub 0) = 0.1. Its (HST) V - I color varies at most from approximately 0.3 mag at a approximately equal to 0.2 sec to approximately 1.2 mag at a approximately greater than 0.4 sec, and possibly to approximately greater than 2.2 mag at a approximately greater than 1.2 sec. Together with its I - K color (approximately equal to 2.5 mag for a approximately greater than 1.0 sec-2.0 sec), this is consistent with an aging stellar population approximately 0.3-0.5 Gyr old in the galaxy center (a approx. less than 2 kpc radius), and possibly approximately 0.5-1.0 Gyr old at a approximately greater than 10 kpc radius. While its outer part may thus have started to collapse at z = 2.5-4, its inner part still is aligned with its redshifted Ly(alpha) cloud and its radio axis, possibly caused by star formation associated with the radio jet, or by reflection from its AGN cone.
- Published
- 1994
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131. The morphology of faint galaxies in Medium Deep Survey images using WFPC2
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Griffiths, R. E, Casertano, S, Ratnatunga, K. U, Neuschaefer, L. W, Ellis, R. S, Gilmore, G. F, Glazebrook, K, Santiago, B, Huchra, J. P, and Windhorst, R. A
- Subjects
Astronomy - Abstract
First results from Hubble Space Telescope (HST) Medium Deep Survey images taken with Wide Field/Planetary Camera-2 (WFPC2) demonstrate that galaxy classifications can be reliably performed to magnitudes I814 approximately less than 22.0 in the F815W band. Published spectroscopic surveys to this depth indicate a mean redshift of bar-z approximately 0.5. We have classified over 200 galaxies in nine WFPC2 fields according to a basic morphological scheme. The majority of these faint galaxies appear to be similar to regular Hubble-sequence examples observed at low redshift. To the precision of our classification scheme, the relative proportion of spheroidal and disk systems of normal appearance is as expected from nearby samples, indicating that the bulk of the local galaxy population was in place at half the Hubble time. However, the most intriguing result is the relatively high proportion (approximately 40%) of objects which are in some way anomalous, and which may be of relevance in understanding the origin of the familiar excess population of faint galaxies established by others. These diverse objects include apparently interacting pairs whose multiple structure is only revealed with HST's angular resolution, galaxies with superluminous star-forming regions, diffuse low surface brightness galaxies of various forms, and compact galaxies. These anomalous galaxies contribute a substantial fraction of the excess counts at our limiting magnitude, and may provide insights into the 'faint blue galaxy' problem.
- Published
- 1994
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- View/download PDF
132. Hubble Space Telescope Medium Deep Survey. 2: Deconvolution of Wide Field Camera field galaxy images in the 13 hour + 43 deg field
- Author
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Windhorst, R. A, Schmidtke, P. C, Pascarelle, S. M, Gordon, J. M, Griffiths, R. E, Ratnatunga, K. U, Neuschaefer, L. W, Ellis, R. S, Gilmore, G, and Glazebrook, K
- Subjects
Astrophysics - Abstract
We present isophotal profiles of six faint field galaxies from some of the first deep images taken for the Hubble Space Telescope (HST) Medium Deep Survey (MDS). These have redshifts in the range z = 0.126 to 0.402. The images were taken with the Wide Field Camera (WFC) in `parallel mode' and deconvolved with the Lucy method using as the point-spread function nearby stars in the image stack. The WFC deconvolutions have a dynamic range of 16 to 20 dB (4 to 5 mag) and an effective resolution approximately less than 0.2 sec (FWHM). The multiorbit HST images allow us to trace the morphology, light profiles, and color gradients of faint field galaxies down to V approximately equal to 22 to 23 mag at sub-kpc resolution, since the redshift range covered is z = 0.1 to 0.4. The goals of the MDS are to study the sub-kpc scale morphology, light profiles, and color gradients for a large samole of faint field galaxies down to V approximately equal to 23 mag, and to trace the fraction of early to late-type galaxies as function of cosmic time. In this paper we study the brighter MDS galaxies in the 13 hour + 43 deg MDS field in detail, and investigate to what extent model fits with pure exponential disks or a(exp 1/4) bulges are justified at V approximately less than 22 mag. Four of the six field galaxies have light profiles that indicate (small) inner bulges following r(exp 1/4) laws down to 0.2 sec resolution, plus a dominant surrounding exponential disk with little or no color gradients. Two occur in a group at z = 0.401, two are barred spiral galaxies at z = 0.179 and z = 0.302, and two are rather subluminous (and edge-on) disk galaxies at z = 0.126 and z = 0.179. Our deep MDS images can detect galaxies down to V, I approximately less than 25 to 26 mag, and demonstrate the impressive potential of HST--even with its pre-refurbished optics--to resolve morphological details in galaxies at cosmologically significant distances (v approximately less than 23 mag). Since the median redshift of these galaxies is approximately less than 0.4, the HST resolution allows us to study sub kpc size scales at the galaxy, which cannot be done with stable images over wide fields from the best ground-based sites.
- Published
- 1994
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133. Initial results from a ROSAT deep survey in Lynx
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Anderson, S. F, Windhorst, R. A, Maccacaro, T, Burstein, D, Franklin, B. E, Griffiths, R. E, Koo, D. C, Mathis, D. F, Morgan, W. A, and Neuschaefer, L. W
- Subjects
Astronomy - Abstract
Preliminary results from a deep (70 ksec) Rosat survey of the high galactic latitude selected area Lynx.3A are presented. Lynx.3A sensitivity was previously studied in both the optical radio, with deep Westerbork surveys and deep multicolor Charge Couple Device (CCD) images form the Palomar 200 inch Four-Shooter. About 70 x-ray sources were detected within the central 40 foot diameter region of the Position Sensitive Proportional Counter (PSPC), observed surface densities of approximately 200 x-ray sources/sq deg are suggested, and these x-ray sources alone account for approximately 30 percent of the cosmic x-ray background (0.9 to 2.2 keV). An initial look at the observed x-ray logN - logS curve is presented, but a detailed assessment requires further study. The 4 sigma limit of about 7 times 10 to the minus 15th power erg/s.sq cm (0.5 to 2.0 keV) is considerably deeper then the Einstein deep surveys, and of comparable sensitivity to the deepest current Rosat surveys. Cross correlation with our Four Shooter optical catalogs yields at least one likely optical candidate for nearly all of the Rosat x-ray sources; a number of the likely optical identifications have colors of quasi-stellar objects (and stellar PSF), but in other cases galaxies/groups are also viable candidates.
- Published
- 1992
134. Deep Extragalactic VIsible Legacy Survey (DEVILS): motivation,design, and target catalogue
- Author
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Davies, L J M, primary, Robotham, A S G, additional, Driver, S P, additional, Lagos, C P, additional, Cortese, L, additional, Mannering, E, additional, Foster, C, additional, Lidman, C, additional, Hashemizadeh, A, additional, Koushan, S, additional, O’Toole, S, additional, Baldry, I K, additional, Bilicki, M, additional, Bland-Hawthorn, J, additional, Bremer, M N, additional, Brown, M J I, additional, Bryant, J J, additional, Catinella, B, additional, Croom, S M, additional, Grootes, M W, additional, Holwerda, B W, additional, Jarvis, M J, additional, Maddox, N, additional, Meyer, M, additional, Moffett, A J, additional, Phillipps, S, additional, Taylor, E N, additional, Windhorst, R A, additional, and Wolf, C, additional
- Published
- 2018
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135. Lyman continuum escape fraction of faint galaxies at z ~ 3.3 in the CANDELS/GOODS-North, EGS, and COSMOS fields with LBC
- Author
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Grazian, A., primary, Giallongo, E., additional, Paris, D., additional, Boutsia, K., additional, Dickinson, M., additional, Santini, P., additional, Windhorst, R. A., additional, Jansen, R. A., additional, Cohen, S. H., additional, Ashcraft, T. A., additional, Scarlata, C., additional, Rutkowski, M. J., additional, Vanzella, E., additional, Cusano, F., additional, Cristiani, S., additional, Giavalisco, M., additional, Ferguson, H. C., additional, Koekemoer, A., additional, Grogin, N. A., additional, Castellano, M., additional, Fiore, F., additional, Fontana, A., additional, Marchi, F., additional, Pedichini, F., additional, Pentericci, L., additional, Amorín, R., additional, Barro, G., additional, Bonchi, A., additional, Bongiorno, A., additional, Faber, S. M., additional, Fumana, M., additional, Galametz, A., additional, Guaita, L., additional, Kocevski, D. D., additional, Merlin, E., additional, Nonino, M., additional, O’Connell, R. W., additional, Pilo, S., additional, Ryan, R. E., additional, Sani, E., additional, Speziali, R., additional, Testa, V., additional, Weiner, B., additional, and Yan, H., additional
- Published
- 2017
- Full Text
- View/download PDF
136. VLA AND ALMA IMAGING OF INTENSE GALAXY-WIDE STAR FORMATION INz∼ 2 GALAXIES
- Author
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Rujopakarn, W., primary, Dunlop, J. S., additional, Rieke, G. H., additional, Ivison, R. J., additional, Cibinel, A., additional, Nyland, K., additional, Jagannathan, P., additional, Silverman, J. D., additional, Alexander, D. M., additional, Biggs, A. D., additional, Bhatnagar, S., additional, Ballantyne, D. R., additional, Dickinson, M., additional, Elbaz, D., additional, Geach, J. E., additional, Hayward, C. C., additional, Kirkpatrick, A., additional, McLure, R. J., additional, Michałowski, M. J., additional, Miller, N. A., additional, Narayanan, D., additional, Owen, F. N., additional, Pannella, M., additional, Papovich, C., additional, Pope, A., additional, Rau, U., additional, Robertson, B. E., additional, Scott, D., additional, Swinbank, A. M., additional, Werf, P. van der, additional, Kampen, E. van, additional, Weiner, B. J., additional, and Windhorst, R. A., additional
- Published
- 2016
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- View/download PDF
137. DO THE MOST MASSIVE BLACK HOLES ATz= 2 GROW VIA MAJOR MERGERS?
- Author
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Mechtley, M., primary, Jahnke, K., additional, Windhorst, R. A., additional, Andrae, R., additional, Cisternas, M., additional, Cohen, S. H., additional, Hewlett, T., additional, Koekemoer, A. M., additional, Schramm, M., additional, Schulze, A., additional, Silverman, J. D., additional, Villforth, C., additional, van der Wel, A., additional, and Wisotzki, L., additional
- Published
- 2016
- Full Text
- View/download PDF
138. Modelling and Simulating Airport Surface Operations with Gate Conflicts.
- Author
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Zelinski, S. and Windhorst, R.
- Abstract
The Surface Operations Simulator and Scheduler (SOSS) is a fast-time simulation of the airport surface used to rapidly develop and test new surface scheduling concepts. Gate conflicts present a challenge for surface scheduling. A late departure pushback or early arrival sharing the same gate can cause a gate conflict, which if left unmanaged, can lead to surface gridlock. Surface scheduling concepts that meter departures at their gates can increase the likelihood of gate conflicts. In real operations, hardstand areas are used to temporality park aircraft out of the way to avoid gate conflicts. New SOSS models and functionality for hardstand operations were developed to simulate gate conflict management approaches using hardstands to temporarily park either the arrival or departure out of the way of the other. Four gate conflict management approaches were simulated with surface scheduling and their effects on surface operations were compared. The four gate conflict management approaches each allowed a unique subset of resolution actions including early departure pushback, sending the departure to the hardstand, and sending the arrival to the hardstand. The gate conflict management approaches allowing arrivals to be sent to the hardstand were found to be most successful in resolving the gate conflicts and maintaining scheduler performance measured by takeoff time predictability. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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139. FIRST RESULTS FROM THE FAINT INFRARED GRISM SURVEY (FIGS): FIRST SIMULTANEOUS DETECTION OF Ly α EMISSION AND LYMAN BREAK FROM A GALAXY AT z = 7.51
- Author
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Tilvi, V., primary, Pirzkal, N., additional, Malhotra, S., additional, Finkelstein, S. L., additional, Rhoads, J. E., additional, Windhorst, R., additional, Grogin, N. A., additional, Koekemoer, A., additional, Zakamska, N. L., additional, Ryan, R., additional, Christensen, L., additional, Hathi, N., additional, Pharo, J., additional, Joshi, B., additional, Yang, H., additional, Gronwall, C., additional, Cimatti, A., additional, Walsh, J., additional, O’Connell, R., additional, Straughn, A., additional, Ostlin, G., additional, Rothberg, B., additional, Livermore, R. C., additional, Hibon, P., additional, and Gardner, Jonathan P., additional
- Published
- 2016
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- View/download PDF
140. Constraining stellar assembly and active galactic nucleus feedback at the peak epoch of star formation
- Author
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Kimm, T., Kaviraj, S., Devriendt, J. E. G., Cohen, S. H., Windhorst, R. A., Dubois, Y., Slyz, A., Hathi, N. P., Ryan, R. E., O’Connell, R. W., Dopita, M. A., Silk, J., Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), and Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,galaxies: high-redshift ,[SDU]Sciences of the Universe [physics] ,Astrophysics::High Energy Astrophysical Phenomena ,ultraviolet: galaxies ,galaxies: formation ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We study stellar assembly and feedback from active galactic nuclei (AGN) around the epoch of peak star formation (1 ≲ z ≲ 2), by comparing hydrodynamic simulations to rest-frame UV-optical galaxy colours from the Wide Field Camera 3 (WFC3) Early Release Science (ERS) programme. Our adaptive mesh refinement simulations include metal-dependent radiative cooling, star formation, kinetic outflows due to supernova explosions and feedback from supermassive black holes. Our model assumes that when gas accretes on to black holes, a fraction of the energy is used to form either thermal winds or subrelativistic momentum-imparting collimated jets, depending on the accretion rate. We find that the predicted rest-frame UV-optical colours of galaxies in the model that includes AGN feedback are in broad agreement with the observed colours of the WFC3 ERS sample at 1 ≲ z ≲ 2. The predicted number of massive galaxies also matches well with observations in this redshift range. However, the massive galaxies are predicted to show higher levels of residual star formation activity than the observational estimates, suggesting the need for further suppression of star formation without significantly altering the stellar mass function. We discuss possible improvements, involving faster stellar assembly through enhanced star formation during galaxy mergers while star formation at the peak epoch is still modulated by the AGN feedback. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.
- Published
- 2012
141. The brown dwarf atmosphere monitoring (BAM) project – II. Multi-epoch monitoring of extremely cool brown dwarfs
- Author
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Rajan, A., primary, Patience, J., additional, Wilson, P. A., additional, Bulger, J., additional, De Rosa, R. J., additional, Ward-Duong, K., additional, Morley, C., additional, Pont, F., additional, and Windhorst, R., additional
- Published
- 2015
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- View/download PDF
142. Optical Spectra of Low Flux Radio Sources
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Koo, D. C., primary, Kron, R. G., additional, and Windhorst, R. A., additional
- Published
- 1989
- Full Text
- View/download PDF
143. Passively Evolving Early-type Galaxies at 1.4
- Author
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Daddi, E., Renzini, A., Pirzkal, N., Cimatti, A., Malhotra, S., Stiavelli, M., Xu, C., Pasquali, A., Rhoads, J. E., Brusa, M., Alighieri, S. di Serego, Ferguson, H. C., Koekemoer, A. M., Moustakas, L. A., Panagia, N., and Windhorst, R. A.
- Subjects
Astrophysics (astro-ph) ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We report on a complete sample of 7 luminous early-type galaxies in the Hubble Ultra Deep Field (UDF) with spectroscopic redshifts between 1.39 and 2.47 and to K1.4. Low-resolution spectra of these objects have been extracted from the HST+ACS grism data taken over the UDF by the GRAPES project. Redshift for the 7 galaxies have been identified based on the UV feature at rest frame 2640=1.7 appears to be roughly a factor of 2--3 smaller than that of their local counterparts, further supporting the notion that such massive and old galaxies are already ubiquitous at early cosmic times. Much smaller effective radii are derived for some of the objects compared to local massive ellipticals, which may be due to morphological K corrections, evolution, or the presence of a central point-like source. Nuclear activity is indeed present in a subset of the galaxies, as revealed by them being hard X-ray sources, hinting to AGN activity having played a role in discontinuing star formation., 18 pages, 15 figures, ApJ in press
- Published
- 2005
- Full Text
- View/download PDF
144. Closing in on the Hydrogen Reionization Edge at z < 7.2 with Deep STIS/CCD Parallels
- Author
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Windhorst, R., primary, Bernstein, R., additional, Collins, N., additional, Plait, P., additional, Woodgate, B., additional, Mather, J., additional, Madau, P., additional, and Shaver, P., additional
- Full Text
- View/download PDF
145. The role of major mergers in the size growth of intermediate-mass spheroids
- Author
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Kaviraj, S., primary, Huertas-Company, M., additional, Cohen, S., additional, Peirani, S., additional, Windhorst, R. A., additional, O'Connell, R. W., additional, Silk, J., additional, Dopita, M. A., additional, Hathi, N. P., additional, Koekemoer, A. M., additional, Mei, S., additional, Rutkowski, M., additional, Ryan, R. E., additional, and Shankar, F., additional
- Published
- 2014
- Full Text
- View/download PDF
146. HST imaging of an old galaxy group at Z=1.55
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Bunker, A, Spinrad, H, McLure, R, Dey, A, Dunlop, J, Peacock, J, Stern, D, Thompson, R, Waddington, I, and Windhorst, R
- Published
- 2002
147. INVESTIGATING THE CORE MORPHOLOGY-SEYFERT CLASS RELATIONSHIP WITHHUBBLE SPACE TELESCOPEARCHIVAL IMAGES OF LOCAL SEYFERT GALAXIES
- Author
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Rutkowski, M. J., primary, Hegel, P. R., additional, Kim, Hwihyun, additional, Tamura, Kazuyuki, additional, and Windhorst, R. A., additional
- Published
- 2013
- Full Text
- View/download PDF
148. STELLAR POPULATIONS OF LYMAN BREAK GALAXIES ATz≃ 1-3 IN THEHST/WFC3 EARLY RELEASE SCIENCE OBSERVATIONS
- Author
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Hathi, N. P., primary, Cohen, S. H., additional, Ryan, R. E., additional, Finkelstein, S. L., additional, McCarthy, P. J., additional, Windhorst, R. A., additional, Yan, H., additional, Koekemoer, A. M., additional, Rutkowski, M. J., additional, O'Connell, R. W., additional, Straughn, A. N., additional, Balick, B., additional, Bond, H. E., additional, Calzetti, D., additional, Disney, M. J., additional, Dopita, M. A., additional, Frogel, Jay A., additional, Hall, D. N. B., additional, Holtzman, J. A., additional, Kimble, R. A., additional, Paresce, F., additional, Saha, A., additional, Silk, J. I., additional, Trauger, J. T., additional, Walker, A. R., additional, Whitmore, B. C., additional, and Young, E. T., additional
- Published
- 2013
- Full Text
- View/download PDF
149. The insignificance of major mergers in driving star formation at z ≃ 2
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Kaviraj, S., primary, Cohen, S., additional, Windhorst, R. A., additional, Silk, J., additional, O'Connell, R. W., additional, Dopita, M. A., additional, Dekel, A., additional, Hathi, N. P., additional, Straughn, A., additional, and Rutkowski, M., additional
- Published
- 2012
- Full Text
- View/download PDF
150. Newborn spheroids at high redshift: when and how did the dominant, old stars in today's massive galaxies form?
- Author
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Kaviraj, S., primary, Cohen, S., additional, Ellis, R. S., additional, Peirani, S., additional, Windhorst, R. A., additional, O’Connell, R. W., additional, Silk, J., additional, Whitmore, B. C., additional, Hathi, N. P., additional, Ryan, R. E., additional, Dopita, M. A., additional, Frogel, J. A., additional, and Dekel, A., additional
- Published
- 2012
- Full Text
- View/download PDF
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