A search for starlight reflected from HD 75289b     

Christopher Leigh  rew Collier Cameron  Stephane Udry  Jean-François Donati  Keith Horne  David James  Alan Penny 《Monthly notices of the Royal Astronomical Society》2003,346(2):L16-L20

We have used a Doppler tomographic analysis to conduct a deep search for the starlight reflected from the planetary companion to HD 75289. In four nights on VLT(UT2)/UVES in 2003 January, we obtained 684 high-resolution echelle spectra with a total integration time of 26 h. We establish an upper limit on the geometric albedo of the planet   p < 0.12  (to the 99.9 per cent significance level) at the most probable orbital inclination   i ≃ 60°  , assuming a grey albedo, a Venus-like phase function and a planetary radius   R _p= 1.6 R_Jup  . We are able to rule out some combinations of the predicted planetary radius and atmospheric albedo models with high, reflective cloud decks.  相似文献   

Kinematically quiet haloes around z∼ 2.5 radio galaxies. Keck spectroscopy     

M. Villar-Martín  J. Vernet  S. di Serego Alighieri  R. Fosbury  A. Humphrey  L. Pentericci 《Monthly notices of the Royal Astronomical Society》2003,346(1):273-294

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An optical and near-infrared search for brown dwarfs in the Pleiades cluster     

Chie Nagashima †  Paul D. Dobbie  Takahiro Nagayama  Yasushi Nakajima  Tetsuya Nagata  Motohide Tamura  Tadashi Nakajima  Koji Sugitani  Hidehiko Nakaya  Simon T. Hodgkin  rew J. Pickles  Shuji Sato 《Monthly notices of the Royal Astronomical Society》2003,343(4):1263-1270

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The GLARE Survey – II. Faint z≈ 6 Lyα line emitters in the HUDF     

Elizabeth R. Stanway †  rew J. Bunker  Karl Glazebrook  Roberto G. Abraham  James Rhoads  Sangeeta Malhotra  David Crampton  Matthew Colless  Kuenley Chiu 《Monthly notices of the Royal Astronomical Society》2007,376(2):727-738

The galaxy population at   z ≈ 6  has been the subject of intense study in recent years, culminating in the Hubble Ultra Deep Field (HUDF) – the deepest imaging survey yet. A large number of high-redshift galaxy candidates have been identified within the HUDF, but until now analysis of their properties has been hampered by the difficulty of obtaining spectroscopic redshifts for these faint galaxies. Our 'Gemini Lyman-Alpha at Reionization Era' (GLARE) project has been designed to undertake spectroscopic follow-up of faint  ( z ' < 28.5)  i '-drop galaxies at   z ≈ 6  in the HUDF. In a previous paper we presented preliminary results from the first 7.5 h of data from GLARE. In this paper we detail the complete survey. We have now obtained 36 h of spectroscopy on a single GMOS slitmask from Gemini-South, with a spectral resolution of  λ/Δλ_FWHM≈ 1000  . We identify five strong Lyα emitters at   z > 5.5  , and a further nine possible line emitters with detections at lower significance. We also place tight constraints on the equivalent width of Lyα emission for a further ten i '-drop galaxies and examine the equivalent width distribution of this faint spectroscopic sample of   z ≈ 6  galaxies. We find that the fraction of galaxies with little or no emission is similar to that at   z ≈ 3  , but that the   z ≈ 6  population has a tail of sources with high rest-frame equivalent widths. Possible explanations for this effect include a tendency towards stronger line emission in faint sources, which may arise from extreme youth or low metallicity in the Lyman-break population at high redshift, or possibly a top-heavy initial mass function.  相似文献   

The stellar mass density at z≈ 6 from Spitzer imaging of i'-drop galaxies     

Laurence P. Eyles  rew J. Bunker  Richard S. Ellis  Mark Lacy  Elizabeth R. Stanway  Daniel P. Stark  Kuenley Chiu 《Monthly notices of the Royal Astronomical Society》2007,374(3):910-930

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Period and chemical evolution of SC stars     

Albert A. Zijlstra  Timothy R. Bedding  rew J. Markwick  Rita Loidl-Gautschy  Vello Tabur  Kristen D. Alexander  rew P. Jacob  László L. Kiss  Aaron Price  Mikako Matsuura  Janet A. Mattei† 《Monthly notices of the Royal Astronomical Society》2004,352(1):325-337

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Marine scientific research and the law of the sea: by Alfred H.A. Soons Kluwer Law and Taxation Publishers,Deventer, The Netherlands, 1982, 383 pp     

George Humphrey 《Marine Policy》1983,7(2):129-130

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Community collaboration and climate change research in the Canadian Arctic     

Tristan D. Pearce  James D. Ford  Gita J. Laidler  Barry Smit  Frank Duerden  Mishak Allarut  Mark Andrachuk  Steven Baryluk  rew Dialla  Pootoogoo Elee  Annie Goose  Theo Ikummaq  Eric Joamie  Fred Kataoyak  Eric Loring  Stephanie Meakin  Scott Nickels  Kip Shappa  Jamal Shirley  & Johanna Wandel 《Polar research》2009,28(1):10-27

Research on climate change impacts, vulnerability and adaptation, particularly projects aiming to contribute to practical adaptation initiatives, requires active involvement and collaboration with community members and local, regional and national organizations that use this research for policy-making. Arctic communities are already experiencing and adapting to environmental and socio-cultural changes, and researchers have a practical and ethical responsibility to engage with communities that are the focus of the research. This paper draws on the experiences of researchers working with communities across the Canadian Arctic, together with the expertise of Inuit organizations, Northern research institutes and community partners, to outline key considerations for effectively engaging Arctic communities in collaborative research. These considerations include: initiating early and ongoing communication with communities, and regional and national contacts; involving communities in research design and development; facilitating opportunities for local employment; and disseminating research findings. Examples of each consideration are drawn from climate change research conducted with communities in the Canadian Arctic.  相似文献   

Accurate estimators of power spectra in N-body simulations     

Stéphane Colombi  rew Jaffe  Dmitri Novikov  Christophe Pichon 《Monthly notices of the Royal Astronomical Society》2009,393(2):511-526

A method to rapidly estimate the Fourier power spectrum of a point distribution is presented. This method relies on a Taylor expansion of the trigonometric functions. It yields the Fourier modes from a number of fast Fourier transforms (FFTs), which is controlled by the order N of the expansion and by the dimension D of the system. In three dimensions, for the practical value   N = 3  , the number of FFTs required is 20.
We apply the method to the measurement of the power spectrum of a periodic point distribution that is a local Poisson realization of an underlying stationary field. We derive an explicit analytic expression for the spectrum, which allows us to quantify – and correct for – the biases induced by discreteness and by the truncation of the Taylor expansion, and to bound the unknown effects of aliasing of the power spectrum. We show that these aliasing effects decrease rapidly with the order N . For   N = 3  , they are expected to be, respectively, smaller than  ∼10⁻⁴  and 0.02 at half the Nyquist frequency and at the Nyquist frequency of the grid used to perform the FFTs. The only remaining significant source of errors is reduced to the unavoidable cosmic/sample variance due to the finite size of the sample.
The analytical calculations are successfully checked against a cosmological N -body experiment. We also consider the initial conditions of this simulation, which correspond to a perturbed grid. This allows us to test a case where the local Poisson assumption is incorrect. Even in that extreme situation, the third-order Fourier–Taylor estimator behaves well, with aliasing effects restrained to at most the per cent level at half the Nyquist frequency.
We also show how to reach arbitrarily large dynamic range in Fourier space (i.e. high wavenumber), while keeping statistical errors in control, by appropriately 'folding' the particle distribution.  相似文献   

Biodiversity of the wetlands of the Kakadu Region, northern Australia     

C. Max Finlayson  John Lowry  Maria Grazia Bellio  Suthidha Nou  Robert Pidgeon  Dave Walden  Chris Humphrey  Gary Fox 《Aquatic Sciences - Research Across Boundaries》2006,68(3):374-399

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