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An FMOS survey of moderate-luminosity broad-line Agn in COSMOS, SXDS and E-CDF-S

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arXiv 2018年

作者： Schulze, Andreas Silverman, John D. Kashino, Daichi Akiyama, Masayuki Schramm, Malte Sanders, Dave Kartaltepe, Jeyhan Daddi, Emanuele Rodighiero, Giulia Renzini, Alvio Arimoto, Nobuo Nagao, Tohru Puglisi, Annagrazia Trakhtenbrot, Benny Civano, Francesca Suh, Hyewon National Astronomical Observatory of Japan Mitaka Tokyo181-8588 Japan University of Tokyo KashiwaChiba277-8583 Japan Department of Physics ETH Zürich Wolfgang-Pauli-strasse 27 ZürichCH-8093 Switzerland Astronomical Institute Tohoku University Aramaki Aobaku Sendai980-8578 Japan Institute for Astronomy University of Hawaii 2680 Wood-lawn Drive HonoluluHI96822 United States School of Physics and Astronomy Rochester Institute of Technology 84 Lomb Memorial Drive RochesterNY14623 United States CEA IRFU DAp AIM Université Paris-Saclay Université Paris Diderot Sorbonne Paris Cité CNRS Gif-surYvetteF-91191 France Dipartimento di Fisica e Astronomia Universita di Padova vicolo Osservatorio 3 PadovaI-35122 Italy Instituto Nazionale de Astrofisica Osservatorio Astronomico di Padova vicolo dell’ Osservatorio 5 PadovaI-35122 Italy Astronomy Program Department of Physics and Astronomy Seoul National University 599 Gwanak-ro Gwanaku-gu Seoul151-742 Korea Republic of Graduate School of Science and Engineering Ehime University 2-5 Bunkyo-cho Matsuyama790-8577 Japan School of Physics and Astronomy Tel Aviv University Tel Aviv69978 Israel Harvard-Smithsonian Center for Astrophysics 60 Garden Street CambridgeMA02138 United States Yale Center for Astronomy and Astrophysics 260 Whitney Avenue New HavenCT06520 United States Subaru Telescope 650 North A’ohoku Place HiloHI96720 United States

We present near-IR spectroscopy in J- and H-band for a large sample of 243 X-ray selected moderate-luminosity type-1 AGN in the COSMOS, SXDS and E-CDF-S survey fields using the multi-object spectrograph Subaru/FMOS. Our sample covers the redshift range 0.5 . z . 3.0 and an X-ray luminosity range of 1043 . L[2−10keV] . 1045 erg s−1. We provide emission-line properties and derived virial black hole mass estimates, bolometric luminosities and Eddington ratios, based on Hα (211), Hβ (63) and Mg II (4). We compare line widths, luminosities and black hole mass estimates from Hα and Hβ and augment these with commensurate measurements of Mg II and C IV detected in optical spectra. We demonstrate the robustness of using Hα, Hβ and Mg II as reliable black hole mass estimators for high-z moderate-luminosity AGN, while the use of C IV is prone to large uncertainties (& 0.4 dex). We extend a recently proposed correction based on the C IV blueshift to lower luminosities and black hole masses. While our sample shows an improvement in their C IV black hole mass estimates, the deficit of high blueshift sources reduces its overall importance for moderate-luminosity AGN, compared to the most luminous quasars. In addition, we revisit luminosity correlations between Lbol, L[2−10keV], L[OIII], L5100 and LHα and find them to be consistent with a simple empirical model, based on a small number of well-established scaling relations. We finally highlight our highest redshift AGN, CID 781, at z = 4.6 which shows the lowest black hole mass (∼ 108M☉) among current near-IR samples at this redshift, and is in a state of fast growth. Copyright © 2018, The Authors. All rights reserved.

关键词： Luminance

Optimization Properties of Environmentally Friendly Paper Coating Based Starch-Polyethylene glycol (PEG) Mixture

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Journal of physics: Conference Series 2017年第1期909卷

作者： Diani Galih Saputri Khairuddin Nanik Dwi Nurhayati Trinh Pham Physics Department of Sebelas Maret University Indonesia 57126 Chemistry (FKIP) Department of Graduate Program Sebelas Maret University Indonesia 57126 Danang University of Science and Technology Vietnam 550000

The use of starch as biodegradable base material for packaging application was of great interest as an environmentally friendly alternative to the present use of polyethylene and polyvinyl chloride. However, starch tended to be brittle and had a lack of stability due to exposure to water. Several aproaches have been done to improve shellac properties including through chemical modification, mixing with polymers, clays, and plasticizers. The present study related to optimization of starch properties when mixing with polyethylene glycol (PEG) coated on the paper. The aim was to obtain the temperature and mixing time between starch and PEG so produced composites with optimal barrier properties. The composites of PEG/starch 10 % w/w were prepared using solvent casting and coated on paper surface, and dried in the oven for 12 hours at 40°C. Water Vapour Transmitter Rate (WVTR) (Payne cup method) showed that 70°C was the optimum temperature when mixing time was 30 minutes. Moreover, it showed that the optimum mixing time was 30 minutes when mixing temperature was 80 and 70 °C. Fourier Transform Infra Red (FTIR) showed a strong interaction between PEG400 and starch.

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Preparation and Characterization of Microwave-absorption of Sarulla North Sumatra Zeolite and Ferric Oxide-filled Polyurethane Nanocomposites

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Procedia Chemistry 2016年 19卷 441-446页

作者： Golfrid Gultom Basuki Wirjosentono Kerista Sebayang Masno Ginting University of Sumatera Utara Physics Post Graduate Program Medan 20155 Indonesia Polytechnic of Chemical Industry Technology Medan 20228 Indonesia University of Sumatera Utara Chemistry Department Medan 20155 Indonesia University of Sumatera Utara Physics Department Medan 20155 Indonesia Indonesian Institute of Science Research Center for Physics Serpong 15314 Indonesia

Microwave-absorptive polymeric composite materials are becoming important to protect interference of any communication systems due to the increase in the use of microwave-inducing devices. In this work, the microwave-absorptive polyurethane composites are prepared using natural zeolites of Sarulla North Sumatra and commercial ferric-oxide as fillers. Weight ratio of the natural zeolite to ferric oxide were varied (18:2; 16:4; 14:6; 12:8 and 10:10) by weight. The fillers are prepared using ball milling technique and characterized using Particle Size Analyzer for particle size distribution. The nanocomposites, prepared using in-situ reaction of polyethylene glycol and toluene diisocyanate, is characterized for physical and mechanical properties using tensile strength, thermal properties with TGA techniques, as well as morphological and chemical properties using scanning electron microscopy. Composition and loading of the nanofillers against polyurethane matrices is 20% by weight. Microwave-absorption properties of the nanocomposites is characterized using 8-12 GHz frequency. Tensile strengths of the natural zeolite-ferric oxides polyurethane nanocomposites shows higher values when matrices filled with lower ferric-oxide, which could be due to the nanozeolites have functioned as reinforcement for the polyurethane matrix through polar-polar interaction between the filler surfaces with the matrices. The microwave absorption properties, which investigated by Vector Network Analyzer, of the nanocomposites filled in polyurethane with the ratio of nanozeolite to ferric oxide filler of 12:8 shows reflection loss of – 13.2 dB. This condition was observed at 11.1 GHz.

关键词： Polyurethane Nanozeolites Microwave-absorption

AKARI mid-infrared slitless spectroscopic survey of star-forming galaxies at z < 0.5

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arXiv 2018年

作者： Ohyama, Y. Wada, T. Matsuhara, H. Takagi, T. Malkan, M. Goto, T. Egami, E. Lee, H.-M. Im, M. Kim, J.-H. Pearson, C. Inami, H. Oyabu, S. Usui, F. Burgarella, D. Mazyed, F. Imanishi, M. Jeong, W.-S. Miyaji, T. Tello, J. Díaz Nakagawa, T. Serjeant, S. Takeuchi, T.T. Toba, Y. White, G.J. Hanami, H. Ishigaki, T. Academia Sinica Institute of Astronomy and Astrophysics 11F of Astronomy-Mathematics Building AS/NTU No. 1 Sec. 4 Roosevelt Rd. Taipei10617 Taiwan Institute of Space and Astronautical Science Japan Aerospace Exploration Agency 3-1-1 Yoshinodai Chuo-ku Sagamihara Kanagawa252-5210 Japan Japan Space Forum Shin-Ochanomizu Urban Trinity Bldg. 2F 3-2-1 Kandasurugadai Chiyoda-ku Tokyo101-0062 Japan Division of Astronomy and Astrophysics University of California Los Angeles 430 Portola Plaza Box 951547 Los AngelesCA90095-1547 United States Dark Cosmology Centre Niels Bohr Institute University of Copenhagen Juliane Maries Vej 30 Copenhagen Ø2100 Denmark National Tsing hua University No. 101 Section 2 Kuang-Fu Road Hsinchu30013 Taiwan Steward Observatory University of Arizona 933 N. Cherry Ave TucsonAZ85721 United States Astronomy Program Department of Physics and Astronomy Seoul National University Shillim-Dong Kwanak-Gu Seoul151-742 Korea Republic of Subaru Telescope National Astronomical Observatory of Japan 650 North Aòhoku Place HiloHI96720 United States RAL Space STFC Rutherford Appleton Laboratory Chilton Didcot OxfordshireOX11 0QX United Kingdom Department of Physics and Astronomy Open University Walton Hall Milton KeynesMK7 6AA United Kingdom Oxford Astrophysics Denys Wilkinson Building University of Oxford Keble Rd OxfordOX1 3RH United Kingdom National Optical Astronomy Observatory 950 North Cherry Avenue TucsonAZ85719 United States CRAL Observatoire de Lyon 9 avenue Charles André Saint Genis Laval69561 France Graduate School of Science Nagoya University Furo-cho Chikusa-ku Nagoya Aichi464-8602 Japan Graduate School of Science University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo113-0033 Japan Center for Planetary Science Graduate School of Science Kobe University 7-1-48 Minatojima-Minamimachi Chuo-Ku Kobe650-0047 Japan Laboratoire d’Astrophysique de Marseille Pôle de l’Étoile Site de Château-Gombert 38 rue F

Context. Deep mid-infrared (MIR) surveys have revealed numerous strongly star-forming galaxies at redshift z . 2. Their MIR fluxes are produced by a combination of continuum and Polycyclic Aromatic Hydrocarbon (PAH) emission features. The PAH features can dominate the total MIR flux, but are difficult to measure without spectroscopy. Aims. We aim to study star-forming galaxies by using a blind spectroscopic survey at MIR wavelengths to understand evolution of their star formation rate (SFR) and specific SFR (SFR per stellar mass) up to z ' 0.5, by paying particular attention to their PAH properties. Methods. We conducted a low-resolution (R ' 50) slitless spectroscopic survey at 5–13 µm of 9 µm flux-selected sources (> 0.3 mJy) around the North Ecliptic Pole with the Infrared Camera (IRC) onboard AKARI. After removing 11 AGN candidates by using the IRC photometry, we identified 48 PAH galaxies with PAH 6.2, 7.7, and 8.6 µm features at z Copyright © 2018, The Authors. All rights reserved.

关键词： Polycyclic aromatic hydrocarbons

Multi-wavelength fibril dynamics and oscillations above sunspot– I. morphological signature

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Research in Astronomy and Astrophysics 2015年第11期15卷 1843-1856页

作者： Emanuel Sungging Mumpuni Dhani Herdiwijaya Mitra Djamal Thomas Djamaluddin Graduate Program in Astronomy Faculty of Mathematics and Natural Sciences Bandung Institute of TechnologyGedung CAS Lt. 6 ITB Jl. Ganesha 10 Bandung 40132 Indonesia Space Science Center LAPAN Graduate Program in Physics Faculty of Mathematics and Natural Sciences Bandung Institute of Technology Department of PhysicsJl. Ganesha 10 Bandung 40132 Indonesia

In this work we selected one particular fibril from a high resolution observation of the solar chromosphere with the Dutch Open Telescope, and tried to obtain a broad picture of the intricate mechanism that might be operating in the multiple layers of the solar atmosphere visible in high cadence multi-wavelength observations. We analyzed the changing fibril pattern using multi-wavelength tomography, which consists of both the Hα line center and the blue wing, Doppler signal, Ca II H, and the G-band. We have found that the intermittent ejected material through the fibril from Doppler images has clearly shown an oscillation mode, as seen in the Hα blue *** oscillations in the umbrae and penumbrae magnetic field lines that are above the sunspot cause a broadening and the area forms a ring shape from 3 to 15 minute oscillations as a function of height. These made a distinct boundary between the umbrae and penumbrae which suggests a comb structure, and indicates that the oscillations could propagate along the inclined magnetic flux tubes from below. The 3 minute oscillations strongly appeared in the broadly inclined penumbrae magnetic field lines and showed a clear light bridge. The well known 5 minute oscillations were dominant in the umbrae-penumbrae region boundary. The long 7 minute oscillations were transparent in the Hα blue wing, as well as the 10 and 15 minute oscillations. They were concentrated in the inner-penumbrae, as seen in the Hα line center. From these findings we propose that the fibril acts as a fabric for interaction between the layers,as well as related activities around the active region under investigation.

关键词： minute morphological signature picture propagate fabric Figure sector visible concentrated

Ultrafast carrier dynamics in BiVO4: Interplay between free carriers, trapped carriers and low-frequency lattice vibrations

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Ultrafast carrier dynamics in BiVO4: Interplay between free ...

International Conference on Infrared and Millimeter Waves

作者： Benjamin J. Dringoli Keith T. Butler Lite Zhou Binod Giri Pratap M. Rao A. Walsh Lyubov V. Titova Department of Physics Worcester Polytechnic Institute Worcester MA USA Department of Chemistry University of Bath UK Materials Science and Engineering Graduate Program Worcester Polytechnic Institute Worcester MA USA

ISBN: (纸本)9781467384865

BiVO 4 is a promising material for solar energy conversion applications. However, it suffers from low mobility due to strong carrier-phonon coupling, which favors formation of polarons. To elucidate carrier transport mechanisms in BiVO 4 , we apply time-resolved THz spectroscopy to probe dynamics of photexcited carriers and their coupling to lattice vibrational modes at early times (1-20 ps) after photoexcitation. We find that at high excitation fluences, trap states are saturated and a short-lived population of highly mobile residual carriers exists. At the same time, saturation of hole trap states manifests itself in changes in the low-frequency (1.92 THz) seesaw phonon mode between the Bi and VO 4 units.

关键词： Absorption Phonons Conductivity Films Lattices Chemistry Couplings

The gravitational field equations of a twisted skyrmion string: numerical solution

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Journal of physics: Conference Series 2017年第1期795卷

作者： Miftachul Hadi Malcolm Anderson Andri Husein Department of Mathematics Universiti Brunei Darussalam NEGARA BRUNEI DARUSSALAM Physics Research Centre Indonesian Institute of Sciences (LIPI) INDONESIA School of Physics Ulsan National Institute of Science and Technology (UNIST) SOUTH KOREA Institute of Modern Physics Chinese Academy of Sciences Lanzhou CHINA Physics Department of Post Graduate Program Sebelas Maret University INDONESIA

We study nonlinear sigma model, especially Skyrme model with twist: twisted Skyrmion string where twist term, mkz, is indicated in vortex solution. To add gravity, we replace gμv in Lagrangian system with a space-time metric tensor, gμv which in view of the time-independence and cylindrical symmetry of the assumed vortex solution is taken to be a function of r alone. We use ode45 for numerical calculation, i.e. a tool box in Matlab to solve coupled Einstein field equations which have ordinary differential equations (ODE) form.

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Constraints on core-collapse supernova progenitors from explosion site integral field spectroscopy

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arXiv 2017年

作者： Kuncarayakti, H. Anderson, J.P. Galbany, L. Maeda, K. Hamuy, M. Aldering, G. Arimoto, N. Doi, M. Morokuma, T. Usuda, T. University of Turku Väisäläntie 20 Piikkiö21500 Finland Tuorla Observatory Department of Physics and Astronomy University of Turku Väisäläntie 20 Piikkiö21500 Finland Millennium Institute of Astrophysics Casilla 36-D Santiago Chile Departamento de Astronomía Universidad de Chile Casilla 36-D Santiago Chile European Southern Observatory Alonso de Córdova 3107 Casilla 19001 Vitacura Santiago Chile PITT PACC Department of Physics and Astronomy University of Pittsburgh PittsburghPA15260 United States Department of Astronomy Graduate School of Science Kyoto University Sakyo-ku Kyoto606-8502 Japan University of Tokyo 5-1-5 Kashiwanoha Kashiwa Chiba277-8583 Japan Physics Division Lawrence Berkeley National Laboratory 1 Cyclotron Road BerkeleyCA94720 United States Astronomy Program Department of Physics and Astronomy Seoul National University 599 Gwanak-ro Gwanak-gu Seoul151-742 Korea Republic of Subaru Telescope National Astronomical Observatory of Japan National Institutes of Natural Sciences 650 North A'ohoku Place HiloHI96720 United States Institute of Astronomy Graduate School of Science University of Tokyo 2-21-1 Osawa Mitaka Tokyo181-0015 Japan Research Center for the Early Universe Graduate School of Science University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo113-0033 Japan National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan

Context. Observationally, supernovae are divided into subclasses pertaining to their distinct characteristics. This diversity naturally reflects the diversity in the progenitor stars. It is not entirely clear however, how different evolutionary paths leading massive stars to become a supernova are governed by fundamental parameters such as progenitor initial mass and metallicity. Aims. This paper places constraints on progenitor initial mass and metallicity in distinct core-collapse supernova subclasses, through a study of the parent stellar populations at the explosion sites. Methods. Integral field spectroscopy (IFS) of 83 nearby supernova explosion sites with a median distance of 18 Mpc has been collected and analysed, enabling detection and spectral extraction of the parent stellar population of supernova progenitors. From the parent stellar population spectrum, the initial mass and metallicity of the coeval progenitor are derived by means of comparison to simple stellar population models and strong-line methods. Additionally, near-infrared IFS was employed to characterise the star formation history at the explosion sites. Results. No significant metallicity differences are observed among distinct supernova types. The typical progenitor mass is found to be highest for supernova type Ic, followed by type Ib, then types IIb and II. Type IIn is the least associated with young stellar populations and thus massive progenitors. However, statistically significant differences in progenitor initial mass are observed only when comparing supernovae IIn with other subclasses. Stripped-envelope SN progenitors with initial mass estimate lower than 25 Moare found;these are thought to be the result of binary progenitors. Confirming previous studies, these results support the notion that core-collapse supernova progenitors cannot arise from single-star channel only, and both single and binary channels are at play in the production of core-collapse supernovae. Near-infrared IFS s

关键词： Supernovae

SciPy 1.0—Fundamental algorithms for scientific computing in python

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arXiv 2019年

作者： Virtanen, Pauli Gommers, Ralf Oliphant, Travis E. Haberland, Matt Reddy, Tyler Cournapeau, David Burovski, Evgeni Peterson, Pearu Weckesser, Warren Bright, Jonathan van der Walt, Stéfan J. Brett, Matthew Wilson, Joshua Millman, K. Jarrod Mayorov, Nikolay Nelson, Andrew R.J. Jones, Eric Kern, Robert Larson, Eric Carey, C.J. Polat, Ilhan Feng, Yu Moore, Eric W. VanderPlas, Jake Laxalde, Denis Perktold, Josef Cimrman, Robert Henriksen, Ian Quintero, E.A. Harris, Charles R. Archibald, Anne M. Ribeiro, Antônio H. Pedregosa, Fabian van Mulbregt, Paul University of Jyväskylä University of Jyväskylä FI-40014 Finland Quansight LLC AustinTX United States Ultrasound Imaging Mayo Clinic RochesterMN55902 United States Electrical Engineering Brigham Young University ProvoUT84604 United States Enthought Inc. AustinTX78701 United States Anaconda Inc AustinTX78701 United States BioResource and Agricultural Engineering Department California Polytechnic State University San Luis ObispoCA93407 United States Department of Mathematics University of California Los AngelesCA90025 United States Los Alamos National Laboratory Los AlamosNM87544 United States Independent Researcher Higher School of Economics Myasnitskaya 20 Moscow101000 Russia Independent Researcher Saue Estonia Department of Mechanics and Applied Mathematics Institute of Cybernetics Tallinn Technical University Akadeemia Rd 21 Tallinn Estonia Independent Researcher NY United States Berkeley Institute for Data Science University of California BerkeleyCA94720 United States School of Psychology University of Birmingham Edgbaston BirmighamB15 2TT United Kingdom Division of Biostatistics University of California BerkeleyCA94720 United States WayRay LLC Skolkovo Innovation Center Moscow143026 Russia Australian Nuclear Science and Technology Organisation Locked Bag 2001 Kirrawee DCNSW2232 Australia Institute for Learning and Brain Sciences University of Washington SeattleWA98195 United States College of Information and Computing Sciences University of Massachusetts Amherst AmherstMA01002 United States Berkeley Center for Cosmological Physics University of California BerkeleyCA94720 United States Bruker Biospin Corp. 15 Fortune Drive BillericaMA01821 United States University of Washington SeattleWA98195 United States New Technologies - Research Centre University of West Bohemia Univerzitní 8 Plzeň306 14 Czech Republic Oden Institute for Computational Engineering and Sciences University of Texas at Austin AustinTX7

SciPy is an open source scientific computing library for the Python programming language. SciPy 1.0 was released in late 2017, about 16 years after the original version 0.1 release. SciPy has become a de facto standard for leveraging scientific algorithms in the Python programming language, with more than 600 unique code contributors, thousands of dependent packages, over 100,000 dependent repositories, and millions of downloads per year. This includes usage of SciPy in almost half of all machine learning projects on GitHub, and usage by high profile projects including LIGO gravitational wave analysis and creation of the first-ever image of a black hole (M87). The library includes functionality spanning clustering, Fourier transforms, integration, interpolation, file I/O, linear algebra, image processing, orthogonal distance regression, minimization algorithms, signal processing, sparse matrix handling, computational geometry, and statistics. In this work, we provide an overview of the capabilities and development practices of the SciPy library and highlight some recent technical developments. Copyright © 2019, The Authors. All rights reserved.

关键词： Open source software