A deeper view of extremely red galaxies: the redshift distribution in the GOODS/CDFS ISAAC field     

K. I. Caputi  J. S. Dunlop  R. J. McLure  N. D. Roche 《Monthly notices of the Royal Astronomical Society》2004,353(1):30-42

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The coincidence and angular clustering of Chandra and SCUBA sources     

O. Almaini  S. E. Scott  J. S. Dunlop  J. C. Manners  C. J. Willott  A. Lawrence  R. J. Ivison  O. Johnson  A. W. Blain  J. A. Peacock  S. J. Oliver  M. J. Fox  R. G. Mann  I. Pérez-Fournon  E. González-Solares  M. Rowan-Robinson  S. Serjeant  F. Cabrera-Guerra  D. H. Hughes 《Monthly notices of the Royal Astronomical Society》2003,338(2):303-311

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Obscured active galactic nuclei from the ELAIS Deep X-ray Survey     

C. J. Willott  C. Simpson  O. Almaini  J. C. Manners  O. Johnson  A. Lawrence  J. S. Dunlop  R. J. Ivison  S. Rawlings  E. González-Solares  I. Pérez-Fournon  S. Serjeant  S. J. Oliver  N. D. Roche  R. G. Mann  M. Rowan-Robinson 《Monthly notices of the Royal Astronomical Society》2003,339(2):397-409

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A sample of radio galaxies spanning three decades in radio luminosity – I. The host galaxy properties and black hole masses     

Ross J. McLure  Chris J. Willott  Matt J. Jarvis  Steve Rawlings  Gary J. Hill  Ewan Mitchell  James S. Dunlop  Margrethe Wold 《Monthly notices of the Royal Astronomical Society》2004,351(1):347-361

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Submillimetre observations of the Hubble Deep Field and Flanking Fields     

S. Serjeant  J. S. Dunlop  R. G. Mann  M. Rowan-Robinson  D. Hughes  A. Efstathiou  A. Blain  M. Fox  R. J. Ivison  T. Jenness  A. Lawrence  M. Longair  S. Oliver  J. A. Peacock 《Monthly notices of the Royal Astronomical Society》2003,344(3):887-904

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The SCUBA HAlf Degree Extragalactic Survey – VI. 350-μm mapping of submillimetre galaxies     

Kristen Coppin  Mark Halpern  Douglas Scott  Colin Borys  James Dunlop  Loretta Dunne  Rob Ivison  Jeff Wagg  Itziar Aretxaga  Elia Battistelli  rew Benson  rew Blain  Scott Chapman  Dave Clements  Simon Dye  Duncan Farrah  David Hughes  Tim Jenness  Eelco van Kampen  Cedric Lacey  Angela Mortier  Alexandra Pope  Robert Priddey  Stephen Serjeant  Ian Smail  Jason Stevens  Mattia Vaccari 《Monthly notices of the Royal Astronomical Society》2008,384(4):1597-1610

A follow-up survey using the Submillimetre High-Angular Resolution Camera (SHARC-II) at 350 μm has been carried out to map the regions around several 850-μm-selected sources from the Submillimetre HAlf Degree Extragalactic Survey (SHADES). These observations probe the infrared (IR) luminosities and hence star formation rates in the largest existing, most robust sample of submillimetre galaxies (SMGs). We measure 350-μm flux densities for 24 850-μm sources, seven of which are detected at ≥2.5σ within a 10 arcsec search radius of the 850-μm positions. When results from the literature are included the total number of 350-μm flux density constraints of SHADES SMGs is 31, with 15 detections. We fit a modified blackbody to the far-IR (FIR) photometry of each SMG, and confirm that typical SMGs are dust-rich  ( M _dust≃ 9 × 10⁸ M_⊙)  , luminous  ( L _FIR≃ 2 × 10¹² L_⊙)  star-forming galaxies with intrinsic dust temperatures of ≃35 K and star formation rates of  ≃400 M_⊙ yr⁻¹  . We have measured the temperature distribution of SMGs and find that the underlying distribution is slightly broader than implied by the error bars, and that most SMGs are at 28 K with a few hotter. We also place new constraints on the 350-μm source counts, N ₃₅₀(>25 mJy) ∼ 200–500 deg⁻².  相似文献   

The SCUBA Half Degree Extragalactic Survey (SHADES) – IX. The environment, mass and redshift dependence of star formation     

S. Serjeant  S. Dye  A. Mortier  J. Peacock  E. Egami  M. Cirasuolo  G. Rieke  C. Borys  S. Chapman  D. Clements  K. Coppin  J. Dunlop  S. Eales  D. Farrah  M. Halpern  P. Mauskopf  A. Pope†  M. Rowan-Robinson  D. Scott  I. Smail  M. Vaccari 《Monthly notices of the Royal Astronomical Society》2008,386(4):1907-1921

We present a comparison between the SCUBA (Submillimetre Common User Bolometer Array) Half Degree Extragalactic Survey (SHADES) at 450 and  850 μm  in the Lockman Hole East with a deep Spitzer Space Telescope survey at  3.6–24 μm  conducted in guaranteed time. Using stacking analyses we demonstrate a striking correspondence between the galaxies contributing the submm extragalactic background light, with those likely to dominate the backgrounds at Spitzer wavelengths. Using a combination BRIzK plus Spitzer photometric redshifts, we show that at least a third of the Spitzer -identified submm galaxies at  1 < z < 1.5  appear to reside in overdensities when the density field is smoothed at 0.5–2 Mpc comoving diameters, supporting the high-redshift reversal of the local star formation–galaxy density relation. We derive the dust-shrouded cosmic star formation history of galaxies as a function of assembled stellar masses. For model stellar masses  <10¹¹ M_⊙  , this peaks at lower redshifts than the ostensible   z ∼ 2.2  maximum for submm point sources, adding to the growing consensus for 'downsizing' in star formation. Our surveys are also consistent with 'downsizing' in mass assembly. Both the mean star formation rates  〈d M _*/d t 〉  and specific star formation rates  〈(1/ M _*) d M _*/d t 〉  are in striking disagreement with some semi-analytic predictions from the Millenium Simulation. The discrepancy could either be resolved with a top-heavy initial mass function, or a significant component of the submm flux heated by the interstellar radiation field.  相似文献   

Clarifying the nature of the brightest submillimetre sources: interferometric imaging of LH 850.02     

J. D. Younger  J. S. Dunlop  A. B. Peck  R. J. Ivison  A. D. Biggs  E. L. Chapin  D. L. Clements  S. Dye  T. R. Greve  D. H. Hughes  D. Iono  I. Smail  M. Krips  G. R. Petitpas  D. Wilner  A. M. Schael  C. D. Wilson 《Monthly notices of the Royal Astronomical Society》2008,387(2):707-712

We present high-resolution interferometric imaging of LH 850.02, the brightest 850- and 1200-μm submillimetre (submm) galaxy in the Lockman Hole. Our observations were made at 890 μm with the Submillimetre Array (SMA). Our high-resolution submm imaging detects LH 850.02 at  ≳6σ  as a single compact (size ≲1 arcsec or ≲8 kpc) point source and yields its absolute position to ∼0.2-arcsec accuracy. LH 850.02 has two alternative radio counterparts within the Submillimetre Common User Bolometer Array (SCUBA) beam (LH 850.02N and LH 850.02S), both of which are statistically very unlikely to be so close to the SCUBA source position by chance. However, the precise astrometry from the SMA shows that the submm emission arises entirely from LH 850.02N, and is not associated with LH 850.02S (by far the brighter of the two alternative identifications at 24 μm). Fits to the optical–infrared (IR) multicolour photometry of LH 850.02N and LH 850.02S indicate that both lie at   z ≈ 3.3  , and are therefore likely to be physically associated. At these redshifts, the 24-μm-to-submm flux density ratios suggest that LH 850.02N has an Arp 220-type starburst-dominated far-IR spectral energy distribution (SED), while LH 850.02S is more similar to Mrk 231, with less dust enshrouded star formation activity, but a significant contribution at 24 μm (rest frame 5–6 μm) from an active nucleus. This complex mix of star formation and active galactic nucleus (AGN) activity in multicomponent sources may be common in the high-redshift ultraluminous galaxy population, and highlights the need for precise astrometry from high-resolution interferometric imaging for a more complete understanding.  相似文献   

A direct comparison of the properties of CRM and VRM in the low-temperature oxidation of magnetite   总被引：1，自引：0，他引：1  

A. K. Gapeev  S. K. Gribov  D. J. Dunlop  Ö. Özdemir  V. P. Shcherbakov 《Geophysical Journal International》1991,105(2):407-418

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First-order reversal curve (FORC) diagrams for pseudo-single-domain magnetites at high temperature     

Adrian R. Muxworthy  David J. Dunlop 《Earth and Planetary Science Letters》2002,203(1):369-382

The recently developed first-order reversal curve (FORC) technique for rapidly examining magnetic domain state has great potential for paleomagnetic and environmental magnetic investigations. However, there are still some gaps in the basic understanding of FORC diagrams, in particular the behavior of pseudo-single-domain (PSD) grains and the contribution of magnetostatic interactions. In this paper we address some of these problems. We report the first FORC diagrams measurements on narrowly sized and well-characterized synthetic PSD through multidomain (MD) magnetite samples. The FORC diagrams evolve with grain size from single-domain (SD)-like to MD-like through the PSD grain size range. Since each sample contains grains of essentially a single size, individual PSD grains evidently contain contributions from both SD-like and MD-like magnetic moments, in proportions that vary with grain size; the evolving FORC diagrams cannot be due to physical mixtures of SD and MD grains of widely different sizes. The FORC diagrams were all asymmetric. Small PSD samples have FORC diagrams with a distinctive closed-contour structure. The distributions of the larger MD grains display no peak, and lie closer to the interaction-field axis. To assess the effect of magnetostatic interactions, we measured FORC diagrams between room temperature and the Curie temperature. On heating the FORC distributions contract without changing shape until ∼500°C. Above this temperature the diagrams become more MD-like, and in addition become more symmetric. The temperature dependence of the interaction-field parameter is proportional to that of the saturation magnetization, in accordance with Néel’s interpretation of the Preisach diagram. The decrease in asymmetry with heating suggests that the origin of the asymmetry lies in magnetostatic interactions. The magnetic hysteresis parameters as a function of temperature were determined from the FORC curves. As the grain size decreased the normalized coercive force was found to decrease more rapidly with temperature.  相似文献