The 2017 Magnetism Roadmap

Sander, D,Valenzuela, S O,Makarov, D,Marrows, C H,Fullerton, E E,Fischer, P,McCord, J,Vavassori, P,Mangin, S,Pirro, P,Hillebrands, B,Kent, A D,Jungwirth, T,Gutfleisch, O,Kim, C G,Berger, A Institute of Physics Publishing Ltd. 2017 Journal of Physics. D, Applied Physics Vol.50 No.36

<P>Building upon the success and relevance of the 2014 Magnetism Roadmap, this 2017 Magnetism Roadmap edition follows a similar general layout, even if its focus is naturally shifted, and a different group of experts and, thus, viewpoints are being collected and presented. More importantly, key developments have changed the research landscape in very relevant ways, so that a novel view onto some of the most crucial developments is warranted, and thus, this 2017 Magnetism Roadmap article is a timely endeavour. The change in landscape is hereby not exclusively scientific, but also reflects the magnetism related industrial application portfolio. Specifically, Hard Disk Drive technology, which still dominates digital storage and will continue to do so for many years, if not decades, has now limited its footprint in the scientific and research community, whereas significantly growing interest in magnetism and magnetic materials in relation to energy applications is noticeable, and other technological fields are emerging as well. Also, more and more work is occurring in which complex topologies of magnetically ordered states are being explored, hereby aiming at a technological utilization of the very theoretical concepts that were recognised by the 2016 Nobel Prize in Physics.</P> <P>Given this somewhat shifted scenario, it seemed appropriate to select topics for this Roadmap article that represent the three core pillars of magnetism, namely magnetic materials, magnetic phenomena and associated characterization techniques, as well as applications of magnetism. While many of the contributions in this Roadmap have clearly overlapping relevance in all three fields, their relative focus is mostly associated to one of the three pillars. In this way, the interconnecting roles of having suitable magnetic materials, understanding (and being able to characterize) the underlying physics of their behaviour and utilizing them for applications and devices is well illustrated, thus giving an accurate snapshot of the world of magnetism in 2017.</P> <P>The article consists of 14 sections, each written by an expert in the field and addressing a specific subject on two pages. Evidently, the depth at which each contribution can describe the subject matter is limited and a full review of their statuses, advances, challenges and perspectives cannot be fully accomplished. Also, magnetism, as a vibrant research field, is too diverse, so that a number of areas will not be adequately represented here, leaving space for further Roadmap editions in the future. However, this 2017 Magnetism Roadmap article can provide a frame that will enable the reader to judge where each subject and magnetism research field stands overall today and which directions it might take in the foreseeable future.</P> <P>The first material focused pillar of the 2017 Magnetism Roadmap contains five articles, which address the questions of atomic scale confinement, 2D, curved and topological magnetic materials, as well as materials exhibiting unconventional magnetic phase transitions. The second pillar also has five contributions, which are devoted to advances in magnetic characterization, magneto-optics and magneto-plasmonics, ultrafast magnetization dynamics and magnonic transport. The final and application focused pillar has four contributions, which present non-volatile memory technology, antiferromagnetic spintronics, as well as magnet technology for energy and bio-related applications. As a whole, the 2017 Magnetism Roadmap article, just as with its 2014 predecessor, is intended to act as a reference point and guideline for emerging research directions in modern magnetism.</P>

THE COSMIC EVOLUTION OF LUMINOUS INFRARED GALAXIES: STRONG INTERACTIONS/MERGERS OF GAS-RICH DISKS

SANDERS D. B. The Korean Astronomical Society 2003 Journal of The Korean Astronomical Society Vol.36 No.3

Deep surveys at mid-infared through submillimeter wavelengths indicate that a substantial fraction of the total luminosity output from galaxies at high redshift (z > 1) emerges at wavelengths 30 - 300${\mu}m$. In addition, much of the star formation and AGN activity associated with galaxy building at these epochs appears to reside in a class of luminous infrared galaxies (LIGs), often so heavily enshrouded in dust that they appear as 'blank-fields' in deep optical/UV surveys. Here we present an update on the state of our current knowledge of the cosmic evolution of LIGs from z = 0 to z $\~$ 4 based on the most recent data obtained from ongoing ground-based redshift surveys of sources detected in ISO and SCUBA deep fields. A scenario for the origin and evolution of LIGs in the local Universe (z < 0.3), based on results from multiwavelength observations of several large complete samples of luminous IRAS galaxies, is then discussed.

AzTEC Millimetre Survey of the COSMOS field – II. Source count overdensity and correlations with large-scale structure

Austermann, J. E.,Aretxaga, I.,Hughes, D. H.,Kang, Y.,Kim, S.,Lowenthal, J. D.,Perera, T. A.,Sanders, D. B.,Scott, K. S.,Scoville, N.,Wilson, G. W.,Yun, M. S. Blackwell Publishing Ltd 2009 Monthly notices of the Royal Astronomical Society Vol.393 No.4

<P>ABSTRACT</P><P>We report an overdensity of bright submillimetre galaxies (SMGs) in the 0.15 deg<SUP>2</SUP> AzTEC/COSMOS survey and a spatial correlation between the SMGs and the optical-IR galaxy density at <I>z</I>≲ 1.1. This portion of the COSMOS field shows a ∼3σ overdensity of robust SMG detections when compared to a background, or ‘blank-field’, population model that is consistent with SMG surveys of fields with no extragalactic bias. The SMG overdensity is most significant in the number of very bright detections (14 sources with measured fluxes <I>S</I><SUB>1.1 mm</SUB> > 6 mJy), which is entirely incompatible with sample variance within our adopted blank-field number densities and infers an overdensity significance of ≫ 4σ. We find that the overdensity and spatial correlation to optical-IR galaxy density are most consistent with lensing of a background SMG population by foreground mass structures along the line of sight, rather than physical association of the SMGs with the <I>z</I>≲ 1.1 galaxies/clusters. The SMG positions are only weakly correlated with weak-lensing maps, suggesting that the dominant sources of correlation are individual galaxies and the more tenuous structures in the survey region, and not the massive and compact clusters. These results highlight the important roles cosmic variance and large-scale structure can play in the study of SMGs.</P>

THE HST COSMOS PROJECT: CONTRIBUTION FROM THE SUBARU TELESCOPE

TANIGUCHI YOSHIAKI,SCOVILLE N. Z.,SANDERS D. B.,MOBASHER B.,AUSSEL H.,CAPAK P.,AJIKI M.,MURAYAMA T.,MIYAZAK S.,KOMIYAMA Y.,SHIOYA Y.,NAGAO T. The Korean Astronomical Society 2005 Journal of The Korean Astronomical Society Vol.38 No.2

The Cosmic Evolution Survey (COSMOS) is a Hubble Space Telescope (HST) treasury project. The COSMOS aims to perform a 2 square degree imaging survey of an equatorial field in I(F814W) band, using the Advanced Camera for Surveys (ACS). Such a wide field survey, combined with ground-based photometric and spectroscopic data, is essential to understand the interplay between large scale structure, evolution and formation of galaxies and dark matter. In 2004, we have obtained high-quality, broad band images of the COSMOS field (B, V, r', i', and z') using Suprime-Cam on the Subaru Telescope, and we have started our new optical multi-band program, COSMOS-21 in 2005. Here, we present a brief summary of the current status of the COSMOS project together with contributions from the Subaru Telescope. Our future Subaru program, COSMOS-21, is also discussed briefly.

AzTEC millimetre survey of the COSMOS field – I. Data reduction and source catalogue

Scott, K. S.,Austermann, J. E.,Perera, T. A.,Wilson, G. W.,Aretxaga, I.,Bock, J. J.,Hughes, D. H.,Kang, Y.,Kim, S.,Mauskopf, P. D.,Sanders, D. B.,Scoville, N.,Yun, M. S. Blackwell Publishing Ltd 2008 MONTHLY NOTICES- ROYAL ASTRONOMICAL SOCIETY Vol.385 No.4

<P>ABSTRACT</P><P>We present a 1.1 mm wavelength imaging survey covering 0.3 deg<SUP>2</SUP> in the COSMOS field. These data, obtained with the AzTEC continuum camera on the James Clerk Maxwell Telescope, were centred on a prominent large-scale structure overdensity which includes a rich X-ray cluster at <I>z</I>≈ 0.73. A total of 50 mm-galaxy candidates, with a significance ranging from 3.5 to 8.5σ, are extracted from the central 0.15 deg<SUP>2</SUP> area which has a uniform sensitivity of ∼1.3 mJy beam<SUP>−1</SUP>. 16 sources are detected with S/N ≥ 4.5, where the expected false-detection rate is zero, of which a surprisingly large number (9) have intrinsic (deboosted) fluxes ≥5 mJy at 1.1 mm. Assuming the emission is dominated by radiation from dust, heated by a massive population of young, optically obscured stars, then these bright AzTEC sources have far-infrared luminosities >6 × 10<SUP>12</SUP> L<SUB>⊙</SUB> and star formation rates >1100 M<SUB>⊙</SUB> yr<SUP>−1</SUP>. Two of these nine bright AzTEC sources are found towards the extreme peripheral region of the X-ray cluster, whilst the remainder are distributed across the larger scale overdensity. We describe the AzTEC data reduction pipeline, the source-extraction algorithm, and the characterization of the source catalogue, including the completeness, flux deboosting correction, false-detection rate and the source positional uncertainty, through an extensive set of Monte Carlo simulations. We conclude with a preliminary comparison, via a stacked analysis, of the overlapping MIPS 24-μm data and radio data with this AzTEC map of the COSMOS field.</P>