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1. Euclid preparation

Author

Collaboration, Euclid, Barnett, R., Warren, S. J., Mortlock, D. J., Cuby, J. -G., Conselice, C., Hewett, P. C., Willott, C. J., Auricchio, N., Balaguera-Antolínez, A., Baldi, M., Bardelli, S., Bellagamba, F., Bender, R., Biviano, A., Bonino, D., Bozzo, E., Branchini, E., Brescia, M., Brinchmann, J., Burigana, C., Camera, S., Capobianco, V., Carbone, C., Carretero, J., Carvalho, C. S., Castander, F. J., Castellano, M., Cavuoti, S., Cimatti, A., Clédassou, R., Congedo, G., Conversi, L., Copin, Y., Corcione, L., Coupon, J., Courtois, H. M., Cropper, M., Da Silva, A., Duncan, C. A. J., Dusini, S., Ealet, A., Farrens, S., Fosalba, P., Fotopoulou, S., Fourmanoit, N., Frailis, M., Fumana, M., Galeotta, S., Garilli, B., Gillard, W., Gillis, B. R., Graciá-Carpio, J., Grupp, F., Hoekstra, H., Hormuth, F., Israel, H., Jahnke, K., Kermiche, S., Kilbinger, M., Kirkpatrick, C. C., Kitching, T., Kohley, R., Kubik, B., Kunz, M., Kurki-Suonio, H., Laureijs, R., Ligori, S., Lilje, P. B., Lloro, I., Maiorano, E., Mansutti, O., Marggraf, O., Martinet, N., Marulli, F., Massey, R., Mauri, N., Medinaceli, E., Mei, S., Mellier, Y., Metcalf, R. B., Metge, J. J., Meylan, G., Moresco, M., Moscardini, L., Munari, E., Neissner, C., Niemi, S. M., Nutma, T., Padilla, C., Paltani, S., Pasian, F., Paykari, P., Percival, W. J., Pettorino, V., Polenta, G., Poncet, M., Pozzetti, L., Raison, F., Renzi, A., Rhodes, J., Rix, H. -W., Romelli, E., Roncarelli, M., Rossetti, E., Saglia, R., Sapone, D., Scaramella, R., Schneider, P., Scottez, V., Secroun, A., Serrano, S., Sirri, G., Stanco, L., Sureau, F., Tallada-Crespí, P., Tavagnacco, D., Taylor, A. N., Tenti, M., Tereno, I., Toledo-Moreo, R., Torradeflot, F., Valenziano, L., Vassallo, T., Wang, Y., Zacchei, A., Zamorani, G., Zoubian, J., Zucca, E., Aix Marseille Université (AMU), INAF - Osservatorio Astronomico di Trieste (OAT), Istituto Nazionale di Astrofisica (INAF), Dipartimento de Fisica Roma Tre (DF-Roma3), Università degli Studi Roma Tre, Consiglio Nazionale delle Ricerche [Bologna] (CNR), Institut de Biologie Intégrative de la Cellule (I2BC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Sénescence et stabilité génomique (SEN), Département Biologie des Génomes (DBG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Biologie Intégrative de la Cellule (I2BC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Astronomia, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Centre National d'Études Spatiales [Toulouse] (CNES), Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Mullard Space Science Laboratory (MSSL), University College of London [London] (UCL), 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Istituto di Astrofisica Spaziale e Fisica Cosmica - Milano (IASF-MI), Royal Observatory Edinburgh (ROE), University of Edinburgh, Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, Département d'Astrophysique (ex SAP) (DAP), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Department of Physics [Helsinki], Falculty of Science [Helsinki], University of Helsinki-University of Helsinki, 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), University of Helsinki, Institut Régional de Médecine Physique et de Réadaptation Louis Pierquin [Nancy] (IRR Louis Pierquin), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Dipartimento di Fisica e Astronomia [Bologna], University of Waterloo [Waterloo], Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Dipartimento di Fisica, Universita` di Roma Tor Vergata, Università degli Studi di Roma Tor Vergata [Roma], INAF - Osservatorio Astronomico di Bologna (OABO), Department of Agricultural, Food and Environmental Sciences, University of Perugia (DSA3), Università degli Studi di Perugia (UNIPG), Department of Biochemistry [Lausanne], Université de Lausanne (UNIL), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), DEMR, ONERA, Université Paris Saclay (COmUE) [Palaiseau], Université Paris Saclay (COmUE)-ONERA, Antarctic Research a European Network for Astrophysics (ARENA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Biomécanique et Bioingénierie (BMBI), Université de Technologie de Compiègne (UTC)-Centre National de la Recherche Scientifique (CNRS), Continental Dynamics Laboratory [CAGS Beijing], Institute of Geology [CAGS Beijing] (CAGS), Chinese Academy of Geological Sciences [Beijing] (CAGS), Ministry of Land and Resources (MLR)-Ministry of Land and Resources (MLR)-Chinese Academy of Geological Sciences [Beijing] (CAGS), Ministry of Land and Resources (MLR)-Ministry of Land and Resources (MLR), Oncology Institute of Southern Switzerland, Euclid Collaboration, Euclid Primeval Universe Science Working Group, Università degli Studi Roma Tre = Roma Tre University (ROMA TRE), 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), Helsingin yliopisto = Helsingfors universitet = University of Helsinki-Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Helsingin yliopisto = Helsingfors universitet = University of Helsinki, 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), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères = Laboratory for Studies of Radiation and Matter in Astrophysics and Atmospheres (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Perugia = University of Perugia (UNIPG), Université de Lausanne = University of Lausanne (UNIL), ONERA-Université Paris Saclay (COmUE), Barnett R., Warren S.J., Mortlock D.J., Cuby J.-G., Conselice C., Hewett P.C., Willott C.J., Auricchio N., Balaguera-Antolinez A., Baldi M., Bardelli S., Bellagamba F., Bender R., Biviano A., Bonino D., Bozzo E., Branchini E., Brescia M., Brinchmann J., Burigana C., Camera S., Capobianco V., Carbone C., Carretero J., Carvalho C.S., Castander F.J., Castellano M., Cavuoti S., Cimatti A., Cledassou R., Congedo G., Conversi L., Copin Y., Corcione L., Coupon J., Courtois H.M., Cropper M., Da Silva A., Duncan C.A.J., Dusini S., Ealet A., Farrens S., Fosalba P., Fotopoulou S., Fourmanoit N., Frailis M., Fumana M., Galeotta S., Garilli B., Gillard W., Gillis B.R., Gracia-Carpio J., Grupp F., Hoekstra H., Hormuth F., Israel H., Jahnke K., Kermiche S., Kilbinger M., Kirkpatrick C.C., Kitching T., Kohley R., Kubik B., Kunz M., Kurki-Suonio H., Laureijs R., Ligori S., Lilje P.B., Lloro I., Maiorano E., Mansutti O., Marggraf O., Martinet N., Marulli F., Massey R., Mauri N., Medinaceli E., Mei S., Mellier Y., Metcalf R.B., Metge J.J., Meylan G., Moresco M., Moscardini L., Munari E., Neissner C., Niemi S.M., Nutma T., Padilla C., Paltani S., Pasian F., Paykari P., Percival W.J., Pettorino V., Polenta G., Poncet M., Pozzetti L., Raison F., Renzi A., Rhodes J., Rix H.-W., Romelli E., Roncarelli M., Rossetti E., Saglia R., Sapone D., Scaramella R., Schneider P., Scottez V., Secroun A., Serrano S., Sirri G., Stanco L., Sureau F., Tallada-Crespi P., Tavagnacco D., Taylor A.N., Tenti M., Tereno I., Toledo-Moreo R., Torradeflot F., Valenziano L., Vassallo T., Wang Y., Zacchei A., Zamorani G., Zoubian J., Zucca E., Astronomy, Helsinki Institute of Physics, Department of Physics, Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Institut de Biologie Intégrative de la Cellule (I2BC), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Università di Bologna [Bologna] (UNIBO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), Institut Régional de Médecine Physique et de Réadaptation [Nancy] (IRR), PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), DEMR, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Biologie Intégrative de la Cellule (I2BC), Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Science and Technology Facilities Council, Science and Technology Facilities Council (STFC), Barnett, R., Warren, S. J., Mortlock, D. J., Cuby, J. -G., Conselice, C., Hewett, P. C., Willott, C. J., Auricchio, N., Balaguera-Antolinez, A., Baldi, M., Bardelli, S., Bellagamba, F., Bender, R., Biviano, A., Bonino, D., Bozzo, E., Branchini, E., Brescia, M., Brinchmann, J., Burigana, C., Camera, S., Capobianco, V., Carbone, C., Carretero, J., Carvalho, C. S., Castander, F. J., Castellano, M., Cavuoti, S., Cimatti, A., Cledassou, R., Congedo, G., Conversi, L., Copin, Y., Corcione, L., Coupon, J., Courtois, H. M., Cropper, M., Da Silva, A., Duncan, C. A. J., Dusini, S., Ealet, A., Farrens, S., Fosalba, P., Fotopoulou, S., Fourmanoit, N., Frailis, M., Fumana, M., Galeotta, S., Garilli, B., Gillard, W., Gillis, B. R., Gracia-Carpio, J., Grupp, F., Hoekstra, H., Hormuth, F., Israel, H., Jahnke, K., Kermiche, S., Kilbinger, M., Kirkpatrick, C. C., Kitching, T., Kohley, R., Kubik, B., Kunz, M., Kurki-Suonio, H., Laureijs, R., Ligori, S., Lilje, P. B., Lloro, I., Maiorano, E., Mansutti, O., Marggraf, O., Martinet, N., Marulli, F., Massey, R., Mauri, N., Medinaceli, E., Mei, S., Mellier, Y., Metcalf, R. B., Metge, J. J., Meylan, G., Moresco, M., Moscardini, L., Munari, E., Neissner, C., Niemi, S. M., Nutma, T., Padilla, C., Paltani, S., Pasian, F., Paykari, P., Percival, W. J., Pettorino, V., Polenta, G., Poncet, M., Pozzetti, L., Raison, F., Renzi, A., Rhodes, J., Rix, H. -W., Romelli, E., Roncarelli, M., Rossetti, E., Saglia, R., Sapone, D., Scaramella, R., Schneider, P., Scottez, V., Secroun, A., Serrano, S., Sirri, G., Stanco, L., Sureau, F., Tallada-Crespi, P., Tavagnacco, D., Taylor, A. N., Tenti, M., Tereno, I., Toledo-Moreo, R., Torradeflot, F., Valenziano, L., Vassallo, T., Wang, Y., Zacchei, A., Zamorani, G., Zoubian, J., and Zucca, E.

Subjects
statistical [Methods], education, Astrophysics, Surveys, Astronomy & Astrophysics, 01 natural sciences, black-holes, Photometry (optics), surveys, quasars: general, 0201 Astronomical and Space Sciences, 0103 physical sciences, ionization, luminosity function, 010303 astronomy & astrophysics, stellar, Physics, methods: statistical, 010308 nuclear & particles physics, ly-alpha emission, Sigma, general [Quasars], Astronomy and Astrophysics, Quasar, neutral hydrogen, accretion flows, z-similar-to-6 quasars, 115 Astronomy, Space science, Astrophysics - Astrophysics of Galaxies, Redshift, Space and Planetary Science, Methods: statistical, Quasars: general, reionization, digital sky survey, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Data release, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We provide predictions of the yield of $78$ may be selected from Euclid $OYJH$ photometry alone, but selection over the redshift interval $77.5$ should be found in the DR1 data release, expected in 2024. It will be possible to determine the bright-end slope of the QLF, $7, Comment: Published in A&A. Updated to match accepted version

Published
2019

2. A complete search for redshift z>6.5 quasars in the VIKING survey

Author

Barnett, R., Warren, S. J., Cross, N. J. G., Mortlock, D. J., Fan, X., Wang, F., and Hewett, P. C.

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences
Abstract

We present the results of a new, deeper, and complete search for high-redshift $6.56.5$ quasars in this field. Additional observations of the other 17 candidates, primarily DESI Legacy Survey photometry and ESO FORS2 spectroscopy, confirm that none is a quasar. This is the first complete sample from the VIKING survey, and we provide the computed selection function. We include a detailed comparison of the BMC method against two other selection methods: colour cuts and minimum-$��^2$ SED fitting. We find that: i) BMC produces eight times fewer false positives than colour cuts, while also reaching 0.3 mag. deeper, ii) the minimum-$��^2$ SED fitting method is extremely efficient but reaches 0.7 mag. less deep than the BMC method, and selects only one of the four known quasars. We show that BMC candidates, rejected because their photometric SEDs have high $��^2$ values, include bright examples of galaxies with very strong [OIII]$����$4959,5007 emission in the $Y$ band, identified in fainter surveys by Matsuoka et al. This is a potential contaminant population in Euclid searches for faint $z>7$ quasars, not previously accounted for, and that requires better characterisation., Accepted for MNRAS

Published
2020
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3. Euclid preparation: V. Predicted yield of redshift 7

Author

Euclid Collaboration, Barnett, R., Warren, S. J., Mortlock, D. J., Cuby, J. -G., Conselice, C., Hewett, P. C., Willott, C. J., Auricchio, N., Balaguera-Antol��nez, A., Baldi, M., Bardelli, S., Bellagamba, F., Bender, R., Biviano, A., Bonino, D., Bozzo, E., Branchini, E., Brescia, M., Brinchmann, J., Burigana, C., Camera, S., Capobianco, V., Carbone, C., Carretero, J., Carvalho, C. S., Castander, F. J., Castellano, M., Cavuoti, S., Cimatti, A., Cl��dassou, R., Congedo, G., Conversi, L., Copin, Y., Corcione, L., Coupon, J., Courtois, H. M., Cropper, M., Da Silva, A., Duncan, C. A. J., Dusini, S., Ealet, A., Farrens, S., Fosalba, P., Fotopoulou, S., Fourmanoit, N., Frailis, M., Fumana, M., Galeotta, S., Garilli, B., Gillard, W., Gillis, B. R., Graci��-Carpio, J., Grupp, F., Hoekstra, H., Hormuth, F., Israel, H., Jahnke, K., Kermiche, S., Kilbinger, M., Kirkpatrick, C. C., Kitching, T., Kohley, R., Kubik, B., Kunz, M., Kurki-Suonio, H., Laureijs, R., Ligori, S., Lilje, P. B., Lloro, I., Maiorano, E., Mansutti, O., Marggraf, O., Martinet, N., Marulli, F., Massey, R., Mauri, N., Medinaceli, E., Mei, S., Mellier, Y., Metcalf, R. B., Metge, J. J., Meylan, G., Moresco, M., Moscardini, L., Munari, E., Neissner, C., Niemi, S. M., Nutma, T., Padilla, C., Paltani, S., Pasian, F., Paykari, P., Percival, W. J., Pettorino, V., Polenta, G., Poncet, M., Pozzetti, L., Raison, F., Renzi, A., Rhodes, J., Rix, H. -W., Romelli, E., Roncarelli, M., Rossetti, E., Saglia, R., Sapone, D., Scaramella, R., Schneider, P., Scottez, V., Secroun, A., Serrano, S., Sirri, G., Stanco, L., Sureau, F., Tallada-Cresp��, P., Tavagnacco, D., Taylor, A. N., Tenti, M., Tereno, I., Toledo-Moreo, R., Torradeflot, F., Valenziano, L., Vassallo, T., Wang, Y., Zacchei, A., Zamorani, G., Zoubian, J., and Zucca, E.

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences
Abstract

We provide predictions of the yield of $78$ may be selected from Euclid $OYJH$ photometry alone, but selection over the redshift interval $77.5$ should be found in the DR1 data release, expected in 2024. It will be possible to determine the bright-end slope of the QLF, $7, Published in A&A. Updated to match accepted version

Published
2019
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4. Black hole mass estimates and emission-line properties of a sample of redshift z>6.5 quasars

Author

De Rosa, G., Venemans, B. P., Decarli, R., Gennaro, M., Simcoe, R. A., Dietrich, M., Peterson, B. M., Walter, F., Frank, S., McMahon, R. G., Hewett, P. C., Mortlock, D. J., and Simpson, C.

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

We present the analysis of optical and near-infrared spectra of the only four $z>6.5$ quasars known to date, discovered in the UKIDSS-LAS and VISTA-VIKING surveys. Our data-set consists of new VLT/X-Shooter and Magellan/FIRE observations. These are the best optical/NIR spectroscopic data that are likely to be obtained for the $z>6.5$ sample using current $6$ - $10$ m facilities. We estimate the black hole mass, the Eddington ratio, and the SiIV/CIV, CIII]/CIV, and FeII/MgII emission-line flux ratios. We perform spectral modeling using a procedure that allows us to derive a probability distribution for the continuum components and to obtain the quasar properties weighted upon the underlying distribution of continuum models. The $z>6.5$ quasars show the same emission properties as their counterparts at lower redshifts. The $z>6.5$ quasars host black holes with masses of $\sim 10^9$ M$_{\odot}$ that are accreting close to the Eddington luminosity ($\langle{\rm log} (L_{\rm Bol}/L_{\rm Edd})\rangle= -0.4\pm0.2$), in agreement with what has been observed for a sample of $4.0, 18 pages, 11 figures. Submitted to ApJ

Published
2013
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6. Forty seven new T dwarfs from the UKIDSS Large Area Survey

Author

Burningham, Ben, Pinfield, D. J., Lucas, P. W., Leggett, S. K., Deacon, N. R., Tamura, M., Tinney, C. G., Lodieu, N., Zhang, Z. H., Huelamo, N., Jones, H. R. A., Murray, D. N., Mortlock, D. J., Patel, M., Navascues, D. Barrado y, Osorio, M. R. Zapatero, Ishii, M., Kuzuhara, M., and Smart, R. L.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, Astrophysics - Astrophysics of Galaxies, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

We report the discovery of 47 new T dwarfs in the Fourth Data Release (DR4) from the Large Area Survey (LAS) of the UKIRT Infrared Deep Sky Survey with spectral types ranging from T0 to T8.5. These bring the total sample of LAS T dwarfs to 80 as of DR4. In assigning spectral types to our objects we have identified 8 new spectrally peculiar objects, and divide 7 of them into two classes. H2O-H-early have a H2O-H index that differs with the H2O-J index by at least 2 sub-types. CH4-J-early have a CH4-J index that disagrees with the H20-J index by at least 2 subtypes. We have ruled out binarity as a sole explanation for both types of peculiarity, and suggest that they may represent hitherto unrecognised tracers of composition and/or gravity. Clear trends in z'(AB)-J and Y-J are apparent for our sample, consistent with weakening absorption in the red wing of the KI line at 0.77microns with decreasing effective temperature. We have used our sample to estimate space densities for T6-T9 dwarfs. By comparing our sample to Monte-Carlo simulations of field T dwarfs for various mass functions of the form phi(M) \propto M^-alpha, we have placed weak constraints on the form of the field mass function. Our analysis suggests that the substellar mass function is declining at lower masses, with negative values of alpha preferred. This is at odds with results for young clusters that have been generally found to have alpha > 0., 23 pages, 10 figures. MNRAS accepted. Version 2 includes omitted authors.

Published
2010
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7. The UKIRT Infrared Deep Sky Survey Second Data Release

Author

Warren, S. J., Cross, N. J. G., Dye, S., Hambly, N. C., Almaini, O., Edge, A. C., Hewett, P. C., Hodgkin, S. T., Irwin, M. J., Jameson, R. F., Lawrence, A., Lucas, P. W., Mortlock, D. J., andrew adamson, Bryant, J., Collins, R. S., Davis, C. J., Emerson, J. P., Evans, D. W., Gonzales-Solares, E. A., Hirst, P., Kerr, T. H., Lewis, J. R., Mann, R. G., Rawlings, M. G., Read, M. A., Riello, M., Sutorius, E. T. W., and Varricatt, W. P.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics
Abstract

The UKIRT Infrared Deep Sky Survey (UKIDSS) is a set of five large near-infrared surveys, covering a complementary range of areas, depths, and Galactic latitudes. The UKIDSS Second Data Release (DR2) includes the First Data Release (DR1), with minor improvements, plus new data for the LAS, GPS, GCS, and DXS, from observations made over 2006 May through July (when the UDS was unobservable). DR2 was staged in two parts. The first part excluded the GPS, and took place on 2007 March 1. The GPS was released on 2007 April 12. DR2 includes 282 sq. degs of multicolour data to (Vega) K=18, complete in the full YJHK set for the LAS, 57 sq. degs in the ZYJHK set for the GCS, and 236 sq. degs in the JHK set for the GPS. DR2 includes nearly 7 sq. degs of deep JK data (DXS, UDS) to an average depth K=21. In addition the release includes a comparable quantity of data where coverage of the filter set for any survey is incomplete. We document changes that have occurred since DR1 to the pipeline, calibration, and archive procedures. The two most noteworthy changes are presentation of the data in a single database (compared to two previously), and provision of additional error flags for detected sources, flagging potentially spurious artifacts, corrupted data and suspected cross-talk sources. We summarise the contents of each of the surveys in terms of filters, areas, and depths., submitted to astro-ph only (not a journal publication) revised in v2 to include GPS details

Published
2007

8. The UKIRT Infrared Deep Sky Survey First Data Release

Author

Warren, S. J., Hambly, N. C., Dye, S., Almaini, O., Cross, N. J. G., Edge, A. C., Foucaud, S., Hewett, P. C., Hodgkin, S. T., Irwin, M. J., Jameson, R. F., Lawrence, A., Lucas, P. W., Adamson, A. J., Bandyopadhyay, R. M., Bryant, J., Collins, R. S., Davis, C. J., Dunlop, J. S., Emerson, J. P., Evans, D. W., Gonzales-Solares, E. A., Hirst, P., Jarvis, M. J., Kendall, T. R., Kerr, T. H., Leggett, S. K., Lewis, J. R., Mann, R. G., McLure, R. J., McMahon, R. G., Mortlock, D. J., Rawlings, M. G., Read, M. A., Riello, M., Simpson, C., Smith, D. J. B., Sutorius, E. T. W., Targett, T. A., and Varricatt, W. P.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics
Abstract

The First Data Release (DR1) of the UKIRT Infrared Deep Sky Survey (UKIDSS) took place on 2006 July 21. UKIDSS is a set of five large near-infrared surveys, covering a complementary range of areas, depths, and Galactic latitudes. DR1 is the first large release of survey-quality data from UKIDSS and includes 320 sq degs of multicolour data to (Vega) K=18, complete (depending on the survey) in three to five bands from the set ZYJHK, together with 4 sq degs of deep JK data to an average depth K=21. In addition the release includes a similar quantity of data with incomplete filter coverage. In JHK, in regions of low extinction, the photometric uniformity of the calibration is better than 0.02 mag. in each band. The accuracy of the calibration in ZY remains to be quantified, and the same is true of JHK in regions of high extinction. The median image FWHM across the dataset is 0.82 arcsec. We describe changes since the Early Data Release in the implementation, pipeline and calibration, quality control, and archive procedures. We provide maps of the areas surveyed, and summarise the contents of each of the five surveys in terms of filters, areas, and depths. DR1 marks completion of 7 per cent of the UKIDSS 7-year goals., Replaced with accepted version. 12 figures. 6 figures are low resolution. Version of paper with full-resolution figures available at http://astro.ic.ac.uk/~sjw4/ukidss_dr1_accepted.ps.gz

Published
2006

9. Non-Gaussianity detections in the Bianchi VIIh corrected WMAP 1-year data made with directional spherical wavelets

Author

McEwen, J. D., Hobson, M. P., Lasenby, A. N., and Mortlock, D. J.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics
Abstract

Many of the current anomalies reported in the Wilkinson Microwave Anisotropy Probe (WMAP) 1-year data disappear after `correcting' for the best-fit embedded Bianchi type VII_h component (Jaffe et al. 2005), albeit assuming no dark energy component. We investigate the effect of this Bianchi correction on the detections of non-Gaussianity in the WMAP data that we previously made using directional spherical wavelets (McEwen et al. 2005a). As previously discovered by Jaffe et al. (2005), the deviations from Gaussianity in the kurtosis of spherical Mexican hat wavelet coefficients are eliminated once the data is corrected for the Bianchi component. This is due to the reduction of the cold spot at Galactic coordinates (l,b)=(209^\circ,-57\circ), which Cruz et al. (2005) claim to be the source of non-Gaussianity introduced in the kurtosis. Our previous detections of non-Gaussianity observed in the skewness of spherical wavelet coefficients are not reduced by the Bianchi correction. Indeed, the most significant detection of non-Gaussianity made with the spherical real Morlet wavelet at a significant level of 98.4% remains (using a very conservative method to estimate the significance). We make our code to simulate Bianchi induced temperature fluctuations publicly available., 11 pages, 8 figures, replaced to match version accepted by MNRAS

Published
2005

10. A high-significance detection of non-Gaussianity in the WMAP 1-year data using directional spherical wavelets

Author

McEwen, J. D., Hobson, M. P., Lasenby, A. N., and Mortlock, D. J.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics
Abstract

A directional spherical wavelet analysis is performed to examine the Gaussianity of the WMAP 1-year data. Such an analysis is facilitated by the introduction of a fast directional continuous spherical wavelet transform. The directional nature of the analysis allows one to probe orientated structure in the data. Significant deviations from Gaussianity are detected in the skewness and kurtosis of spherical elliptical Mexican hat and real Morlet wavelet coefficients for both the WMAP and Tegmark et al. (2003) foreground-removed maps. The previous non-Gaussianity detection made by Vielva et al. (2003) using the spherical symmetric Mexican hat wavelet is confirmed, although their detection at the 99.9% significance level is only made at the 95.3% significance level using our most conservative statistical test. Furthermore, deviations from Gaussianity in the skewness of spherical real Morlet wavelet coefficients on a wavelet scale of 550 arcmin (corresponding to an effective global size on the sky of approximately 26 degrees and an internal size of 3 degrees) at an azimuthal orientation of 72 degrees, are made at the 98.3% significance level, using the same conservative method. The wavelet analysis inherently allows one to localise on the sky those regions that introduce skewness and those that introduce kurtosis. Preliminary noise analysis indicates that these detected deviation regions are not atypical and have average noise dispersion. Further analysis is required to ascertain whether these detected regions correspond to secondary or instrumental effects, or whether in fact the non-Gaussianity detected is due to intrinsic primordial fluctuations in the cosmic microwave background., Comment: 14 pages, 10 figures, references added, replaced to match version accepted by MNRAS

Published
2004
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11. A fast directional continuous spherical wavelet transform

Author

McEwen, J. D., Hobson, M. P., Lasenby, A. N., and Mortlock, D. J.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics
Abstract

A fast algorithm for Antoine and Vandergheynst's (1998) directional continuous spherical wavelet transform (CSWT) is presented. Computational requirements are reduced by a factor of O(\sqrt{N}), when N is the number of pixels on the sphere. The spherical Mexican hat wavelet Gaussianity analysis of the WMAP 1-year data performed by Vielva et al. (2003) is reproduced and confirmed using the fast CSWT. The proposed extension to directional analysis is inherently afforded by the fast CSWT algorithm., Comment: 4 pages, 2 figures, XXXIXth Recontres de Moriond

Published
2004
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12. Reconstruction of total solar irradiance 1974–2009

Author

Ball, W. T., Unruh, Y., Krivova, N. A., Solanki, S. K., Wenzler, T., Mortlock, D. J., and Jaffe, A. H.

Subjects
13. Climate action, Sunspots, Sun: activity, 500: Naturwissenschaften, Sun: photosphere, Sun: faculae, plages
Abstract

Context: The study of variations in total solar irradiance (TSI) is important for understanding how the Sun affects the Earth’s climate. Aims: Full-disk continuum images and magnetograms are now available for three full solar cycles. We investigate how modelled TSI compares with direct observations by building a consistent modelled TSI dataset. The model, based only on changes in the photospheric magnetic flux can then be tested on rotational, cyclical and secular timescales. Methods: We use Kitt Peak and SoHO/MDI continuum images and magnetograms in the SATIRE-S model to reconstruct TSI over cycles 21-23. To maximise independence from TSI composites, SORCE/TIM TSI data are used to fix the one free parameter of the model. We compare and combine the separate data sources for the model to estimate an uncertainty on the reconstruction and prevent any additional free parameters entering the model. Results: The reconstruction supports the PMOD composite as being the best historical record of TSI observations, although on timescales of the solar rotation the IRMB composite provides somewhat better agreement. Further to this, the model is able to account for 92% of TSI variations from 1978 to 2009 in the PMOD composite and over 96% during cycle 23. The reconstruction also displays an inter-cycle, secular decline of 0.20 (+0.12, −0.09) Wm−2 between cycle 23 minima, in agreement with the PMOD composite. Conclusions: SATIRE-S is able to recreate TSI observations on all timescales of a day and longer over 31 years from 1978. This is strong evidence that changes in photospheric magnetic flux alone are responsible for almost all solar irradiance variations over the last three solar cycles.

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