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3. Revealing the star formation history of a mature galaxy cluster at z=2

Author

Trudeau, Ariane, Willis, Jon, Rennehan, Douglas, Canning, Rebecca, and Noordeh, Emil

Subjects
Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

At z=1.98, XLSSC 122 is a massive and mature galaxy cluster with 37 spectroscopically confirmed members. We employ12 band PSF-matched photometry and BAGPIPES SED modelling to investigate the star formation histories, stellar mass, dust and metal content of the 37 confirmed members. XLSSC 122 therefore provides a unique opportunity to explore massive galaxy evolution in dense environments at early times. The galaxy star formation history results can be placed in the context of the cluster accretion history, using cosmological simulations such as the MultiDark Planck 2 simulation. We demonstrate that red-sequence galaxies display a range of ages, from greater than 2 Gyrs for the BCG to 0.5 Gyr for the less massive satellite galaxies. Comparisons with simulated galaxy clusters show that the oldest cluster members formed when XLSSC 122 had assembled 10 to 30% of its z=2 mass, a result that provides an important new view of the mass-scale associated with both the onset and cessation of star formation in this cluster., AT is supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) Postgraduate Scholarship-Doctoral Program. JPW acknowledges support from the NSERC Discovery Grant program.

Published
2021
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4. K2: A new method for the detection of galaxy clusters based on CFHTLS multicolor images

Author

Thanjavur, Karun, Willis, Jon, and Crampton, David

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

We have developed a new method, K2, optimized for the detection of galaxy clusters in multicolor images. Based on the Red Sequence approach, K2 detects clusters using simultaneous enhancements in both colors and position. The detection significance is robustly determined through extensive Monte-Carlo simulations and through comparison with available cluster catalogs based on two different optical methods, and also on X-ray data. K2 also provides quantitative estimates of the candidate clusters' richness and photometric redshifts. Initially K2 was applied to 161 sq deg of two color gri images of the CFHTLS-Wide data. Our simulations show that the false detection rate, at our selected threshold, is only ~1%, and that the cluster catalogs are ~80% complete up to a redshift of 0.6 for Fornax-like and richer clusters and to z ~0.3 for poorer clusters. Based on Terapix T05 release gri photometric catalogs, 35 clusters/sq deg are detected, with 1-2 Fornax-like or richer clusters every two square degrees. Catalogs containing data for 6144 galaxy clusters have been prepared, of which 239 are rich clusters. These clusters, especially the latter, are being searched for gravitational lenses -- one of our chief motivations for cluster detection in CFHTLS. The K2 method can be easily extended to use additional color information and thus improve overall cluster detection to higher redshifts. The complete set of K2 cluster catalogs, along with the supplementary catalogs for the member galaxies, are available on request from the authors., Comment: Accepted in ApJ. 25 pages, including 10 figures. Latex with emulateapj v03/07/07

Published
2009
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5. Serendipity and the SDSS: Discovery of the Largest Known Planetary Nebula on the Sky

Author

Hewett, Paul C, Irwin, Michael J, Skillman, Evan D, Foltz, Craig B, Willis, Jon P, Warren, Stephen J, and Walton, Nicholas A

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Investigation of spectra from the Sloan Digital Sky Survey reveals the presence of a region of ionized gas of >2 degrees diameter centered approximately at alpha = 10^h 37^m delta = -00^o 18' (J2000) (Galactic coordinates l=248, b=+48). [OIII] 4959,5007 emission is particularly strong and emission from H-alpha and [NII] 6548,6583 is also detectable over a substantial area on the sky. The combination of emission line ratios, the close to zero heliocentric radial velocity and the morphology of the structure are consistent with an identification as a very nearby planetary nebula. The proximity of the hot, DO white dwarf PG1034+001 further strengthens this interpretation. The object is: i) the largest planetary nebula on the sky, ii) certainly closer than any planetary nebula other than Sh 2--216, iii) the first to be unambiguously associated with a DO white dwarf. A parallax distance for PG1034+001 would establish whether the structure is in fact the closest, and one of the physically largest, planetary nebula known., 12 pages including 4 figures. ApJ Letters in press

Published
2003
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6. High-Redshift Gravitationally Lensed Galaxies and Tunable Filter Imaging

Author

Hewett, Paul C., Warren, Stephen J., Willis, Jon P., Bland-Hawthorn, Joss, and Lewis, Geraint F.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Most surveys for multiply-imaged gravitational lenses, outside of rich galaxy clusters, are based on sifting through large samples of distant sources to identify the rare examples of lensing. An alternative strategy, based on the selection of optimal lines-of-sight, offers a number of significant advantages. Utilising the multiplex capability of wide-area multifibre spectroscopy, together with tunable Fabry-Perot imaging, it is now possible to undertake such investigations. Progress in compiling a sample of high-redshift star-forming galaxies, gravitationally lensed by massive early-type galaxies at intermediate redshift, z~0.4, is described., Comment: 6 pages, 3 figures, to appear in proceedings of conference ``Imaging the Universe in Three Dimensions'', Walnut Creek, California, March 1999

Published
1999
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7. The Detailed Science Case for the Maunakea Spectroscopic Explorer: the Composition and Dynamics of the Faint Universe

Author

Mcconnachie, Alan, Babusiaux, Carine, Balogh, Michael, Driver, Simon, Côté, Pat, Courtois, Helene, Davies, Luke, Ferrarese, Laura, Gallagher, Sarah, Ibata, Rodrigo, Martin, Nicolas, Robotham, Aaron, Venn, Kim, Villaver, Eva, Bovy, Jo, Boselli, Alessandro, Colless, Matthew, Comparat, Johan, Denny, Kelly, Duc, Pierre-Alain, Ellison, Sara, Grijs, Richard, Fernandez-Lorenzo, Mirian, Freeman, Ken, Guhathakurta, Raja, Hall, Patrick, Hopkins, Andrew, Hudson, Mike, Johnson, Andrew, Kaiser, Nick, Koda, Jun, Konstantopoulos, Iraklis, Koshy, George, Lee, Khee-Gan, Nusser, Adi, Pancoast, Anna, Peng, Eric, Peroux, Celine, Petitjean, Patrick, Pichon, Christophe, Poggianti, Bianca, Schmid, Carlo, Shastri, Prajval, Shen, Yue, Willot, Chris, Croom, Scott, Lallement, Rosine, Schimd, Carlo, Smith, Dan, Walker, Matthew, Willis, Jon, Colless, Alessandro Bosselli Matthew, Goswami, Aruna, Jarvis, Matt, Jullo, Eric, Kneib, Jean-Paul, Konstantopoloulous, Iraklis, Newman, Jeff, Richard, Johan, Sutaria, Firoza, Taylor, Edwar, Waerbeke, Ludovic, Battaglia, Giuseppina, Hall, Pat, Haywood, Misha, Sakari, Charli, Seibert, Arnaud, Thirupathi, Sivarani, Wang, Yuting, Wang, Yiping, Babas, Ferdinand, Bauman, Steve, Caffau, Elisabetta, Laychak, Mary Beth, Crampton, David, Devost, Daniel, Flagey, Nicolas, Han, Zhanwen, Higgs, Clare, Hill, Vanessa, Ho, Kevin, Isani, Sidik, Mignot, Shan, Murowinski, Rick, Pandey, Gajendra, Salmon, Derrick, Siebert, Arnaud, Simons, Doug, Starkenburg, Else, Szeto, Kei, Tully, Brent, Vermeulen, Tom, Withington, Kanoa, Arimoto, Nobuo, Asplund, Martin, Aussel, Herve, Bannister, Michele, Bhatt, Harish, Bhargavi, Ss, Blakeslee, John, Bland-Hawthorn, Joss, Bullock, James, Burgarella, Denis, Chang, Tzu-Ching, Cole, Andrew, Cooke, Jeff, Cooper, Andrew, Di Matteo, Paola, Favole, Ginevra, Flores, Hector, Gaensler, Bryan, Garnavich, Peter, Karoline Gilbert, Gonzalez-Delgado, Rosa, Guhathakurta, Puragra, Hasinger, Guenther, Herwig, Falk, Hwang, Narae, Jablonka, Pascale, Jarvis, Matthew, Kamath, Umanath, Kewley, Lisa, Le Borgne, Damien, Lewis, Geraint, Lupton, Robert, Martell, Sarah, Mateo, Mario, Mena, Olga, Nataf, David, Newman, Jeffrey, Pérez, Enrique, Prada, Francisco, Puech, Mathieu, Recio-Blanco, Alejandra, Robin, Annie, Saunders, Will, Smith, Daniel, Stalin, C. S., Tao, Charling, Thanjuvur, Karun, Tresse, Laurence, Waerbeke, Ludo, Wang, Jian-Min, Yong, David, Zhao, Gongbo, Boisse, Patrick, Bolton, James, Bonifacio, Piercarlo, Bouchy, Francois, Cowie, Len, Cunha, Katia, Deleuil, Magali, Mooij, Ernst, Dufour, Patrick, Foucaud, Sebastien, Glazebrook, Karl, Hutchings, John, Kobayashi, Chiaki, Kudritzki, Rolf-Peter, Li, Yang-Shyang, Lin, Lihwai, Lin, Yen-Ting, Makler, Martin, Narita, Norio, Park, Changbom, Ransom, Ryan, Ravindranath, Swara, Eswar Reddy, Bacham, Sawicki, Marcin, Simard, Luc, Srianand, Raghunathan, Storchi-Bergmann, Thaisa, Umetsu, Keiichi, Wang, Ting-Gui, Woo, Jong-Hak, Wu, Xue-Bing, 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), Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), NRC Herzberg Institute of Astrophysics, National Research Council of Canada (NRC), 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), Departamento de FisicaTeorica e IFT-UAM/CSIC, Universidad Autónoma de Madrid (UAM), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / 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), Cornell Lab of Ornithology, Cornell University [New York], Recherches Epistémologiques et Historiques sur les Sciences Exactes et les Institutions Scientifiques (REHSEIS (UMR_7596)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of Edinburgh, Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-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), CSIRO Digital Productivity Flagship, Public Health Agency of Canada, Laboratoire d'Astrophysique de Toulouse-Tarbes, École normale supérieure - Lyon (ENS Lyon)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Department of Electrical and Computer Engineering [Minneapolis] (ECE), University of Minnesota [Twin Cities] (UMN), University of Minnesota System-University of Minnesota System, Herzberg Institute of Astrophysics, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Department of electronic engineering, Chang Gung University, Canada-France-Hawaii Telescope Corporation (CFHT), National Research Council of Canada (NRC)-Centre National de la Recherche Scientifique (CNRS)-University of Hawai'i [Honolulu] (UH), Anglo-Australian Observatory (AAO), AUTRES, Instituto de Fisica Corpuscular (IFIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universitat de València (UV), Instituto de Astrofísica de Andalucía (IAA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), 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), Cosmological Impact of the First Stars (CIFIST), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Département de médecine oncologique, CRLCC Paul Strauss, Centre for Astrophysics and Supercomputing [Swinburne] (CAS), Swinburne University of Technology [Melbourne], Laboratoire Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Department of Chemical and Biomolecular Engineering, School of Physics, Korea Institute for Advanced Study (KIAS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Études des Structures, des Processus d’Adaptation et des Changements de l’Espace (ESPACE), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Avignon Université (AU)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), 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), Universidad Autonoma de Madrid (UAM), Cornell University, Recherches Epistémologiques et Historiques sur les Sciences Exactes et les Institutions Scientifiques (REHSEIS), PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), University of Minnesota [Twin Cities], Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Consejo Superior de Investigaciones Científicas [Spain] (CSIC)-Universitat de València (UV), Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), PSL Research University (PSL)-PSL Research University (PSL), 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), 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)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), 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), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Cornell Laboratory of Ornithology, Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), and Cornell Lab of Ornithology [New York]

Subjects
[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Astrophysics of Galaxies, Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics::Galaxy Astrophysics
Abstract

MSE is an 11.25m aperture observatory with a 1.5 square degree field of view that will be fully dedicated to multi-object spectroscopy. More than 3200 fibres will feed spectrographs operating at low (R ~ 2000 - 3500) and moderate (R ~ 6000) spectral resolution, and approximately 1000 fibers will feed spectrographs operating at high (R ~ 40000) resolution. MSE is designed to enable transformational science in areas as diverse as tomographic mapping of the interstellar and intergalactic media; the in-situ chemical tagging of thick disk and halo stars; connecting galaxies to their large scale structure; measuring the mass functions of cold dark matter sub-halos in galaxy and cluster-scale hosts; reverberation mapping of supermassive black holes in quasars; next generation cosmological surveys using redshift space distortions and peculiar velocities. MSE is an essential follow-up facility to current and next generations of multi-wavelength imaging surveys, including LSST, Gaia, Euclid, WFIRST, PLATO, and the SKA, and is designed to complement and go beyond the science goals of other planned and current spectroscopic capabilities like VISTA/4MOST, WHT/WEAVE, AAT/HERMES and Subaru/PFS. It is an ideal feeder facility for E-ELT, TMT and GMT, and provides the missing link between wide field imaging and small field precision astronomy. MSE is optimized for high throughput, high signal-to-noise observations of the faintest sources in the Universe with high quality calibration and stability being ensured through the dedicated operational mode of the observatory. (abridged), Comment: 210 pages, 91 figures. Exposure draft. Appendices to the Detailed Science Case can be found at http://mse.cfht.hawaii.edu/docs/

8. Hawk-I - First Results from Science Verification

Author

Kissler-Patig, Markus, Fontana, Andrea, Venemans, Bram, Kneib, Jean-Paul, Doherty, Michelle, Lidman, Christopher, Kuntschner, Harald, Mark Norris, Larsen, Soeren, Gieles, Mark, Mora Fernandes, Alcione, Mccaughrean, Mark, Preibisch, Thomas, Seifahrt, Andreas, Willis, Jon, and Wehner, Elizabeth

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