检索结果-内蒙古大学图书馆

The collapsed tetragonal phase as a strongly covalent and fully nonmagnetic state: Persistent magnetism with interlayer As-As bond formation in Rh-doped Ca0.8Sr0.2Fe2As2

arXiv

引用

arXiv 2017年

作者： Zhao, K. Glasbrenner, J.K. Gretarsson, H. Schmitz, D. Bednarcik, J. Etter, M. Sun, J.P. Manna, R.S. Al-Zein, A. Lafuerza, S. Scherer, W. Cheng, J.G. Gegenwart, P. Experimentalphysik VI Center for Electronic Correlations and Magnetism University of Augsburg Augsburg86159 Germany Department of Computational and Data Sciences Computational Materials Science Center George Mason University 4400 University Drive FairfaxVA22030 National Research Council/Code 6393 Naval Research Laboratory WashingtonDC20375 United States Max-Planck-Institut für Festkörperforschung Heisenbergstraße 1 StuttgartD-70569 Germany CPM Institute of Physics University of Augsburg Augsburg86135 Germany Hamburg22607 Germany Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing100190 China European Synchrotron Radiation Facility BP 220 Grenoble CedexF-38043 France

A well-known feature of CaFe2As2-based superconductors is the pressure-induced collapsed tetragonal phase that is commonly ascribed to the formation of an interlayer As-As bond. Using detailed X-ray scattering and spectroscopy, we find that Rh-doped Ca0.8Sr0.2Fe2As2does not undergo a firstorder phase transition and that local Fe moments persist despite the formation of interlayer As-As bonds. Our density functional theory calculations reveal that the Fe-As bond geometry is critical for stabilizing magnetism and that the pressure-induced drop in the c lattice parameter observed in pure CaFe2As2is mostly due to a constriction within the FeAs planes. These phenomena are best understood using an often overlooked explanation for the equilibrium Fe-As bond geometry, which is set by a competition between covalent bonding and exchange splitting between strongly hybridized Fe 3d and As 4p states. In this framework, the collapsed tetragonal phase emerges when covalent bonding completely wins out over exchange splitting. Thus the collapsed tetragonal phase is properly understood as a strong, covalent phase that is fully nonmagnetic with the As-As bond forming as a byproduct. Copyright © 2017, The Authors. All rights reserved.

关键词： Lattice theory

来源：评论

学校读者我要写书评

暂无评论

Euclid preparation: XV. Forecasting cosmological constraints for the Euclid and CMB joint analysis

arXiv

引用

arXiv 2021年

作者： Ilić, Stéphane Aghanim, N. Baccigalupi, C. Bermejo-Climent, J.R. Fabbian, G. Legrand, L. Paoletti, D. Ballardini, M. Archidiacono, M. Douspis, M. Finelli, F. Ganga, K. Hernández-Monteagudo, C. Lattanzi, M. Marinucci, D. Migliaccio, M. Carbone, C. Casas, S. Martinelli, M. Tutusaus, I. Natoli, P. Ntelis, P. Pagano, L. Wenzl, L. Gruppuso, A. Kitching, T. Langer, M. Mauri, N. Patrizii, L. Renzi, A. Sirri, G. Stanco, L. Tenti, M. Vielzeuf, P. Lacasa, F. Polenta, G. Yankelevich, V. Blanchard, A. Sakr, Z. Pourtsidou, A. Camera, S. Cardone, V.F. Kilbinger, M. Kunz, M. Markovic, K. Pettorino, V. Sánchez, A.G. Sapone, D. Amara, A. Auricchio, N. Bender, R. Bodendorf, C. Bonino, D. Branchini, E. Brescia, M. Brinchmann, J. Capobianco, V. Carretero, J. Castander, F.J. Castellano, M. Cavuoti, S. Cimatti, A. Cledassou, R. Congedo, G. Conselice, C.J. Conversi, L. Copin, Y. Corcione, L. Costille, A. Cropper, M. da Silva, A. Degaudenzi, H. Dubath, F. Duncan, C.A.J. Dupac, X. Dusini, S. Ealet, A. Farrens, S. Fosalba, P. Frailis, M. Franceschi, E. Franzetti, P. Fumana, M. Garilli, B. Gillard, W. Gillis, B. Giocoli, C. Grazian, A. Grupp, F. Guzzo, L. Haugan, S.V.H. Hoekstra, H. Holmes, W. Hormuth, F. Hudelot, P. Jahnke, K. Kermiche, S. Kiessling, A. Kohley, R. Kubik, B. Kümmel, M. Kurki-Suonio, H. Laureijs, R. Ligori, S. Lilje, P.B. Lloro, I. Mansutti, O. Marggraf, O. Marulli, F. Massey, R. Maurogordato, S. Meneghetti, M. Merlin, E. Meylan, G. Moresco, M. Morin, B. Moscardini, L. Munari, E. Niemi, S.M. Padilla, C. Paltani, S. Pasian, F. Pedersen, K. Percival, W. Pires, S. Poncet, M. Popa, L. Pozzetti, L. Raison, F. Rebolo, R. Rhodes, J. Roncarelli, M. Rossetti, E. Saglia, R. Scaramella, R. Schneider, P. Secroun, A. Seidel, G. Serrano, S. Sirignano, C. Starck, J.L. Tallada-Crespí, P. Taylor, A.N. Tereno, I. Toledo-Moreo, R. Torradeflot, F. Valentijn, E.A. Valenziano, L. Kleijn, G.A. Verdoes Wang, Y. Welikala, N. Université PSL Observatoire de Paris Sorbonne Université CNRS LERMA ParisF-75014 France CEICO Institute of Physics The Czech Academy of Sciences Na Slovance 2 Praha 8 Czech Republic Université de Toulouse CNRS UPS CNES 14 Av. Edouard Belin ToulouseF-31400 France Université Paris-Saclay CNRS Institut d'Astrophysique Spatiale Orsay91405 France IFPU Institute for Fundamental Physics of the Universe via Beirut 2 Trieste34151 Italy SISSA International School for Advanced Studies Via Bonomea 265 TS TriesteI-34136 Italy INFN Sezione di Trieste Via Valerio 2 TS TriesteI-34127 Italy INAF-Osservatorio Astronomico di Trieste Via G. B. Tiepolo 11 TriesteI-34131 Italy Departamento de Astrofísica Universidad de La Laguna Tenerife La LagunaE-38206 Spain INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna Via Piero Gobetti 93/3 BolognaI-40129 Italy INFN-Bologna Via Irnerio 46 BolognaI-40126 Italy Center for Computational Astrophysics Flatiron Institute 162 5th Avenue 10010 New YorkNY United States Université de Genève Département de Physique Théorique Centre for Astroparticle Physics 24 quai Ernest-Ansermet Genève 4CH-1211 Switzerland INFN-Sezione di Bologna Viale Berti Pichat 6/2 BolognaI-40127 Italy Dipartimento di Fisica e Astronomia Universitá di Bologna Via Gobetti 93/2 BolognaI-40129 Italy Dipartimento di Fisica 'Aldo Pontremoli' Universitá degli Studi di Milano Via Celoria 16 MilanoI-20133 Italy INFN-Sezione di Milano Via Celoria 16 MilanoI-20133 Italy Université de Paris CNRS Astroparticule et Cosmologie ParisF-75013 France Instituto de Astrofísica de Canarias Calle Vía Làctea s/n Tenerife San Cristòbal de la Laguna38204 Spain Plaza San Juan 1 planta 2 TeruelE-44001 Spain Istituto Nazionale di Fisica Nucleare Sezione di Ferrara Via Giuseppe Saragat 1 FerraraI-44122 Italy Dipartimento di Fisica Università di Roma Tor Vergata Via della Ricerca Scientifica 1 Roma Italy INFN Sezione di Roma 2 V

The combination and cross-correlation of the upcoming Euclid data with cosmic microwave background (CMB) measurements is a source of great expectation since it will provide the largest lever arm of epochs, ranging from recombination to structure formation across the entire past light cone. In this work, we present forecasts for the joint analysis of Euclid and CMB data on the cosmological parameters of the standard cosmological model and some of its extensions. This work expands and complements the recently published forecasts based on Euclid-specific probes, namely galaxy clustering, weak lensing, and their cross-correlation. With some assumptions on the specifications of current and future CMB experiments, the predicted constraints are obtained from both a standard Fisher formalism and a posterior-fitting approach based on actual CMB data. Compared to a Euclid-only analysis, the addition of CMB data leads to a substantial impact on constraints for all cosmological parameters of the standard Λ-cold-dark-matter model, with improvements reaching up to a factor of ten. For the parameters of extended models, which include a redshift-dependent dark energy equation of state, non-zero curvature, and a phenomenological modification of gravity, improvements can be of the order of two to three, reaching higher than ten in some cases. The results highlight the crucial importance for cosmological constraints of the combination and cross-correlation of Euclid probes with CMB data. Copyright © 2021, The Authors. All rights reserved.

关键词： Forecasting

来源：评论

学校读者我要写书评

暂无评论

The broad absorption line tidal disruption event iPTF15af: Optical and ultraviolet evolution

arXiv

引用

arXiv 2018年

作者： Blagorodnova, N. Cenko, S.B. Kulkarni, S.R. Arcavi, I. Bloom, J.S. Duggan, G. Filippenko, A.V. Fremling, C. Horesh, A. Hosseinzadeh, G. Karamehmetoglu, E. Levan, A. Masci, F.J. Nugent, P.E. Pasham, D.R. Veilleux, S. Walters, R. Yan, L. Zheng, W. Cahill Center for Astrophysics California Institute of Technology PasadenaCA91125 United States Joint Space-Science Institute University of Maryland College ParkMD20742 United States NASA Goddard Space Flight Center Mail Code 661 GreenbeltMD20771 United States Department of Physics University of California Santa BarbaraCA93106-9530 United States Las Cumbres Observatory 6740 Cortona Dr Ste 102 GoletaCA93117-5575 United States Department of Astronomy University of California BerkeleyCA94720-3411 United States Miller Institute for Basic Research in Science University of California BerkeleyCA94720 United States Racah Institute of Physics The Hebrew University of Jerusalem Jerusalem91904 Israel Harvard-Smithsonian Center for Astrophysics 60 Garden Street CambridgeMA02138-1516 United States Department of Astronomy Oskar Klein Centre Stockholm University AlbaNova Stockholm10691 Sweden Department of Physics University of Warwick CoventryCV4 7AL United Kingdom Infrared Processing and Analysis Center California Institute of Technology PasadenaCA91125 United States Computational Science Department Lawrence Berkeley National Laboratory 1 Cyclotron Road MS 50B-4206 BerkeleyCA94720 United States Massachusetts Institute of Technology CambridgeMA02139 United States Department of Astronomy University of Maryland Stadium Drive College ParkMD20742-2421 United States

We present multiwavelength observations of the tidal disruption event (TDE) iPTF15af, discovered by the intermediate Palomar Transient Factory (iPTF) survey at redshift z = 0.07897. The optical and ultraviolet (UV) light curves of the transient show a slow decay over five months, in agreement with previous optically discovered TDEs. It also has a comparable black-body peak luminosity of Lpeak ≈ 1.2 × 1044 erg. The inferred temperature from the optical and UV data shows a constant value of (3−5) ×104 K. The transient is not detected in X-rays up to LX 42 erg s−1 within the first five months after discovery. The optical spectra exhibit two distinct broad emission lines in the He ii region, and at later times also Hα emission. Additionally, emission from [N iii] and [O iii] is detected, likely produced by the Bowen fluorescence effect. UV spectra reveal broad emission and absorption lines associated with high-ionization states of N v, C iv, Si iv, and possibly P v. These features, analogous to those of broad absorption line quasars (BAL QSOs), require an absorber with column densities NH > 1023 cm−2. This optically thick gas would also explain the nondetection in soft X-rays. The profile of the absorption lines with the highest column density material at the largest velocity is opposite that of BAL QSOs. We suggest that radiation pressure generated by the TDE flare at early times could have provided the initial acceleration mechanism for this gas. Spectral line monitoring of future TDEs could test this proposal. Copyright © 2018, The Authors. All rights reserved.

关键词： Ionization of gases

来源：评论

学校读者我要写书评

暂无评论

Virtual states in the complex scaling method

引用

AIP Conference Proceedings 2018年第1期2038卷

作者： Kiyoshi Katō Myagmarjav Odsuren Takayuki Myo Hiroshi Masui Yuma Kikuchi 1Nuclear Data Center Faculty of Science Hokkaido University Sapporo 060-0810 Japan 2School of Engineering and Applied Sciences Nuclear Research Center National University of Mongolia Ulaanbaatar 210646 Mongolia 3General Education Faculty of Engineering Osaka Institute of Technology Osaka 535-8585 Japan 4Research Center for Nuclear Physics (RCNP) Osaka University Ibaraki 567-0047 Japan 5Information Processing Center Kitami Institute of Technology Kitami 090-8507 Japan 6Department of Physics Osaka City University Osaka 558-8585 Japan

A virtual state plays an important role in reaction cross sections just above the breakup threshold energy, such as producing the peak behaviour. However, the virtual state cannot be directly obtained as an isolated pole solution in the complex scaling method (CSM) because of a limit of the scaling angle in the CSM. Recently, we proposed a useful approach to find the pole position of the virtual state using the continuum level density (CLD), the scattering phase shift, and scattering length calculated in the CSM [4]. On the basis of the proposed method, we investigate the photo-disintegration cross sections of resonance and virtual states above the threshold energy to see their differences.

关键词：

来源：评论

学校读者我要写书评

暂无评论

The L 98-59 System: Three Transiting, Terrestrial-Sized Planets Orbiting a Nearby M-dwarf

arXiv

引用

arXiv 2019年

作者： Kostov, Veselin B. Schlieder, Joshua E. Barclay, Thomas Quintana, Elisa V. Colón, Knicole D. Brande, Jonathan Collins, Karen A. Feinstein, Adina D. Hadden, Samuel Kane, Stephen R. Kreidberg, Laura Kruse, Ethan Lam, Christopher Matthews, Elisabeth Montet, Benjamin T. Pozuelos, Francisco J. Stassun, Keivan G. Winters, Jennifer G. Ricker, George Vanderspek, Roland Latham, David Seager, Sara Winn, Joshua Jenkins, Jon M. Afanasev, Dennis Armstrong, James J.D. Arney, Giada Boyd, Patricia Barentsen, Geert Barkaoui, Khalid Batalha, Natalie E. Beichman, Charles Bayliss, Daniel Burke, Christopher Burdanov, Artem Cacciapuoti, Luca Carson, Andrew Charbonneau, David Christiansen, Jessie Ciardi, David Clampin, Mark Collins, Kevin I. Conti, Dennis M. Coughlin, Jeffrey Covone, Giovanni Crossfield, Ian Delrez, Laetitia Domagal-Goldman, Shawn Dressing, Courtney Ducrot, Elsa Essack, Zahra Everett, Mark E. Fauchez, Thomas Foreman-Mackey, Daniel Gan, Tianjun Gilbert, Emily Gillon, Michaël Gonzales, Erica Hamann, Aaron Hedges, Christina Hocutt, Hannah Hoffman, Kelsey Horch, Elliott P. Horne, Keith Howell, Steve Hynes, Shane Ireland, Michael Irwin, Jonathan M. Isopi, Giovanni Jensen, Eric L.N. Jehin, Emmanuël Kaltenegger, Lisa Kielkopf, John F. Kopparapu, Ravi Lewis, Nikole Lopez, Eric Lissauer, Jack J. Mann, Andrew W. Mallia, Franco Mandell, Avi Matson, Rachel A. Mazeh, Tsevi Monsue, Teresa Moran, Sarah E. Moran, Vickie Morley, Caroline V. Morris, Brett Muirhead, Philip Mukai, Koji Mullally, Susan Mullally, Fergal Murray, Catriona Narita, Norio Palle, Enric Pidhorodetska, Daria Quinn, David Relles, Howard Rinehart, Stephen Ritsko, Matthew Rodriguez, Joseph E. Rowden, Pamela Rowe, Jason F. Sebastian, Daniel Sefako, Ramotholo Shahaf, Sahar Shporer, Avi Reyes, Naylynn Tañón Tenenbaum, Peter Ting, Eric B. Twicken, Joseph D. van Belle, Gerard T. Vega, Laura Volosin, Jeffrey Walkowicz, Lucianne M. Youngblood, Allison NASA Goddard Space Flight Center GreenbeltMD20771 United States SETI Institute 189 Bernardo Ave Suite 200 Mountain ViewCA94043 United States University of Maryland Baltimore County 1000 Hilltop Cir BaltimoreMD21250 United States University of Maryland College ParkMD20742 United States Sellers Exoplanet Environments Collaboration United States Harvard-Smithsonian Center for Astrophysics 60 Garden St CambridgeMA02138 United States Department of Astronomy and Astrophysics University of Chicago 5640 S. Ellis Ave ChicagoIL60637 United States Department of Earth and Planetary Sciences University of California RiversideCA92521 United States Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology CambridgeMA02139 United States Institute Université de Liège 19C Allée du 6 Août Liège4000 Belgium Astrobiology Research Unit Université de Liège 19C Allée du 6 Août Liège4000 Belgium Vanderbilt University NashvilleTN37240 United States Department of Physics Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology CambridgeMA02139 United States Department of Earth Atmospheric and Planetary Sciences MIT CambridgeMA02139 United States Department of Aeronautics and Astronautics MIT CambridgeMA02139 United States Department of Astrophysical Sciences Princeton University PrincetonNJ08544 United States NASA Ames Research Center Moffett FieldCA94035 United States George Washington University 2121 I St NW WashingtonDC20052 United States University of Hawaii Institute for Astronomy 34 Ohia Ku Street PukalaniHI96768 United States Bay Area Environmental Research Institute P.O. Box 25 Moffett FieldCA Oukaimeden Observatory High Energy Physics and Astrophysics Laboratory Cadi Ayyad University Marrakech Morocco Department of Astronomy and Astrophysics University of California Santa CruzCA95064 United States NASA Exoplanet Science Institute Infrared Processing and Analysis C

We report the Transiting Exoplanet Survey Satellite (TESS) discovery of three terrestrial-sized planets transiting L 98-59 (TOI-175, TIC 307210830) – a bright M dwarf at a distance of 10.6 pc. Using the Gaia-measured distance and broad-band photometry we find that the host star is an M3 dwarf. Combined with the TESS transits from three sectors, the corresponding stellar parameters yield planet radii ranging from 0.8R to 1.6R. All three planets have short orbital periods, ranging from 2.25 to 7.45 days with the outer pair just wide of a 2:1 period resonance. Diagnostic tests produced by the TESS data Validation Report and the vetting package DAVE rule out common false positive sources. These analyses, along with dedicated follow-up and the multiplicity of the system, lend confidence that the observed signals are caused by planets transiting L 98-59 and are not associated with other sources in the field. The L 98-59 system is interesting for a number of reasons: the host star is bright (V = 11.7 mag, K = 7.1 mag) and the planets are prime targets for further follow-up observations including precision radial-velocity mass measurements and future transit spectroscopy with the James Webb Space Telescope;the near resonant configuration makes the system a laboratory to study planetary system dynamical evolution;and three planets of relatively similar size in the same system present an opportunity to study terrestrial planets where other variables (age, metallicity, etc.) can be held constant. L 98-59 will be observed in 4 more TESS sectors, which will provide a wealth of information on the three currently known planets and have the potential to reveal additional planets in the system. Copyright © 2019, The Authors. All rights reserved.

关键词： Satellites

来源：评论

学校读者我要写书评

暂无评论

Gaia DR2 unravels incompleteness of nearby cluster population: New open clusters in the direction of Perseus

arXiv

引用

arXiv 2018年

作者： Cantat-Gaudin, T. Krone-Martins, A. Sedaghat, N. Farahi, A. de Souza, R.S. Skalidis, R. Malz, A.I. Macêdo, S. Moews, B. Jordi, C. Moitinho, A. Castro-Ginard, A. Ishida, E.E.O. Heneka, C. Boucaud, A. Trindade, A.M.M. Martí i Franquès 1 BarcelonaE-08028 Spain CENTRA Faculdade de Ciências Universidade de Lisboa Ed. C8 Campo Grande Lisboa1749-016 Portugal Department of Computer Science University of Freiburg Georges-Koehler-Allee 052 Freiburg79110 Germany McWilliams Center for Cosmology Department of Physics Carnegie Mellon University 5000 Forbes Ave. PittsburghPA15213 United States Department of Physics & Astronomy University of North Carolina Chapel HillNC27599-3255 United States Department of Physics Institute for Theoretical and Computational Physics University of Crete HeraklionGR-71003 Greece Foundation for Research and Technology – Hellas IESL Voutes HeraklionGR-7110 Greece Center for Cosmology and Particle Physics New York University 726 Broadway New YorkNY10004 United States Department of Physics New York University 726 Broadway New YorkNY10004 United States Instituto Federal de Educação Ciência e Tecnologia de Pernambuco IFPE Recife-PE50670-430 Brazil Institute for Astronomy University of Edinburgh Blackford Hill EdinburghEH9 3HJ United Kingdom Université Clermont Auvergne CNRS/IN2P3 LPC Clermont-FerrandF-63000 France Scuola Normale Superiore Piazza dei Cavalieri 7 Pisa56126 Italy LAL Univ. Paris-Sud CNRS/IN2P3 Université Paris-Saclay Orsay France Paris-Saclay Center for Data Science Université Paris-Saclay Orsay France Instituto de Astrofísica e Ciências do Espaço Universidade do Porto CAUP Rua das Estrelas Porto4150-762 Portugal

Context. Open clusters (OCs) are popular tracers of the structure and evolutionary history of the Galactic disk. The OC population is often considered to be complete within 1.8 kpc of the Sun. The recent Gaia data Release 2 (DR2) allows the latter claim to be challenged. Aims. We perform a systematic search for new OCs in the direction of Perseus using precise and accurate astrometry from Gaia DR2. Methods. We implement a coarse-to-fine search method. First, we exploit spatial proximity using a fast density-aware partitioning of the sky via a k-d tree in the spatial domain of Galactic coordinates, (l, b). Secondly, we employ a Gaussian mixture model in the proper motion space to quickly tag fields around OC candidates. Thirdly, we apply an unsupervised membership assignment method, UPMASK, to scrutinise the candidates. We visually inspect colour-magnitude diagrams to validate the detected objects. Finally, we perform a diagnostic to quantify the significance of each identified overdensity in proper motion and in parallax space. Results. We report the discovery of 41 new stellar clusters. This represents an increment of at least 20% of the previously known OC population in this volume of the Milky Way. We also report on the clear identification of NGC 886, an object previously considered an asterism. This study challenges the previous claim of a near-complete sample of open clusters up to 1.8 kpc. Our results reveal that this claim requires revision, and a complete census of nearby open clusters is yet to be found. Copyright © 2018, The Authors. All rights reserved.

关键词： Object detection

来源：评论

学校读者我要写书评

暂无评论

Euclid: Forecasts for k-cut 3 × 2 point statistics

arXiv

引用

arXiv 2020年

作者： Taylor, Peter L. Kitching, T. Cardone, V.F. Ferté, A. Huff, E.M. Bernardeau, F. Rhodes, J. Deshpande, A.C. Tutusaus, I. Pourtsidou, A. Camera, S. Carbone, C. Casas, S. Martinelli, M. Pettorino, V. Sakr, Z. Sapone, D. Yankelevich, V. Auricchio, N. Balestra, A. Bodendorf, C. Bonino, D. Boucaud, A. Branchini, E. Brescia, M. Capobianco, V. Carretero, J. Castellano, M. Cavuoti, S. Cimatti, A. Cledassou, R. Congedo, G. Conversi, L. Corcione, L. Cropper, M. Franceschi, E. Garilli, B. Gillis, B. Giocoli, C. Guzzo, L. Haugan, S.V.H. Holmes, W. Hormuth, F. Jahnke, K. Kermiche, S. Kilbinger, M. Kunz, M. Kurki-Suonio, H. Ligori, S. Lilje, P.B. Lloro, I. Marggraf, O. Markovic, K. Massey, R. Medinaceli, E. Mei, S. Meneghetti, M. Meylan, G. Moresco, M. Morin, B. Moscardini, L. Niemi, S. Padilla, C. Paltani, S. Pasian, F. Pedersen, K. Percival, W.J. Pires, S. Polenta, G. Poncet, M. Popa, L. Raison, F. Roncarelli, M. Rossetti, E. Saglia, R. Schneider, P. Secroun, A. Seidel, G. Serrano, S. Sirignano, C. Sirri, G. Sureau, F. Crespí, P. Tallada Tavagnacco, D. Taylor, A.N. Teplitz, H.I. Tereno, I. Toledo-Moreo, R. Valentijn, E.A. Valenziano, L. Vassallo, T. Wang, Y. Weller, J. Zacchei, A. Zoubian, J. Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive PasadenaCA91109 United States Mullard Space Science Laboratory University College London Holmbury St Mary Dorking SurreyRH5 6NT United Kingdom INAF-Osservatorio Astronomico di Roma Via Frascati 33 Monteporzio CatoneI-00078 Italy Institut de Physique Théorique CEA CNRS Université Paris-Saclay Gif-sur-Yvette CedexF-91191 France Institut d'Astrophysique de Paris 98bis Boulevard Arago ParisF-75014 France Campus UAB Carrer de Can Magrans s/n Barcelona08193 Spain Carrer Gran Capitá 2-4 Barcelona08034 Spain School of Physics and Astronomy Queen Mary University of London Mile End Road LondonE1 4NS United Kingdom INFN-Sezione di Torino Via P. Giuria 1 TorinoI-10125 Italy Dipartimento di Fisica Universitá degli Studi di Torino Via P. Giuria 1 TorinoI-10125 Italy INAF-IASF Milano Via Alfonso Corti 12 MilanoI-20133 Italy AIM CEA CNRS Université Paris-Saclay Université Paris Diderot Sorbonne Paris Cité Gif-sur-YvetteF-91191 France Instituto de Física Téorica UAM-CSIC Campus de Cantoblanco MadridE-28049 Spain Université St Joseph UR EGFEM Faculty of Sciences Beirut Lebanon Université de Toulouse CNRS UPS CNES 14 Av. Edouard Belin ToulouseF-31400 France Departamento de Física FCFM Universidad de Chile Blanco Encalada 2008 Santiago Chile Astrophysics Research Institute Liverpool John Moores University 146 Brownlow Hill LiverpoolL3 5RF United Kingdom INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna Via Piero Gobetti 93/3 BolognaI-40129 Italy INAF-Osservatorio Astronomico di Padova Via dell'Osservatorio 5 PadovaI-35122 Italy Max Planck Institute for Extraterrestrial Physics Giessenbachstr. 1 GarchingD-85748 Germany INAF-Osservatorio Astrofisico di Torino Via Osservatorio 20 TO Pino TorineseI-10025 Italy Université de Paris CNRS Astroparticule et Cosmologie ParisF-75006 France INFN-Sezione di Roma Tre Via della Vasca Nava

Modelling uncertainties at small scales, i.e. high k in the power spectrum P(k), due to baryonic feedback, nonlinear structure growth and the fact that galaxies are biased tracers poses a significant obstacle to fully leverage the constraining power of the Euclid wide-field survey. k-cut cosmic shear has recently been proposed as a method to optimally remove sensitivity to these scales while preserving usable information. In this paper we generalise the k-cut cosmic shear formalism to 3 × 2 point statistics and estimate the loss of information for different k-cuts in a 3 × 2 point analysis of the Euclid data. Extending the Fisher matrix analysis of Euclid Collaboration: Blanchard et al. (2019), we assess the degradation in constraining power for different k-cuts. We work in the idealised case and assume the galaxy bias is linear, the covariance is Gaussian, while neglecting uncertainties due to photo-z errors and baryonic feedback. We find that taking a k-cut at 2.6 h Mpc-1 yields a dark energy Figure of Merit (FOM) of 1018. This is comparable to taking a weak lensing cut at = 5000 and a galaxy clustering and galaxy-galaxy lensing cut at = 3000 in a traditional 3 ×2 point analysis. We also find that the fraction of the observed galaxies used in the photometric clustering part of the analysis is one of the main drivers of the FOM. Removing 50% (90%) of the clustering galaxies decreases the FOM by 19% (62%). Given that the FOM depends so heavily on the fraction of galaxies used in the clustering analysis, extensive efforts should be made to handle the real-world systematics present when extending the analysis beyond the luminous red galaxy (LRG) sample. © 2020, CC BY.

关键词： Galaxies

来源：评论

学校读者我要写书评

暂无评论

Global, regional, and national sex-specific burden and control of the HIV epidemic, 1990–2019, for 204 countries and territories: the Global Burden of Diseases Study 2019

引用

The Lancet HIV 2021年第10期8卷 e633-e651页

作者： Jahagirdar, Deepa Walters, Magdalene K. Novotney, Amanda Brewer, Edmond D. Frank, Tahvi D. Carter, Austin Biehl, Molly H. Abbastabar, Hedayat Abhilash, E.S. Abu-Gharbieh, Eman Abu-Raddad, Laith Jamal Adekanmbi, Victor Adeyinka, Daniel Adedayo Adnani, Qorinah Estiningtyas Sakilah Afzal, Saira Aghababaei, Soodabeh Ahinkorah, Bright Opoku Ahmad, Sajjad Ahmadi, Keivan Ahmadi, Sepideh Ahmadpour, Ehsan Ahmed, Muktar Beshir Rashid, Tarik Ahmed Salih, Yusra Ahmed Aklilu, Addis Akram, Tayyaba Akunna, Chisom Joyqueenet Al Hamad, Hanadi Alahdab, Fares Alanezi, Fahad Mashhour Aleksandrova, Ekaterina A. Alene, Kefyalew Addis Ali, Liaqat Alipour, Vahid Almustanyir, Sami Alvis-Guzman, Nelson Ameyaw, Edward Kwabena Amu, Hubert Andrei, Catalina Liliana Andrei, Tudorel Anvari, Davood Arabloo, Jalal Aremu, Olatunde Arulappan, Judie Atnafu, Desta Debalkie Quintanilla, Beatriz Paulina Ayala Ayza, Muluken Altaye Azari, Samad Darshan, B.B. Banach, Maciej Bärnighausen, Till Winfried Barra, Fabio Barrow, Amadou Basu, Sanjay Bazargan-Hejazi, Shahrzad Belay, Habtamu Gebrehana Berheto, Tezera Moshago Bezabhe, Woldesellassie Mequanint Bezabih, Yihienew Mequanint Bhagavathula, Akshaya Srikanth Bhardwaj, Nikha Bhardwaj, Pankaj Bhattacharyya, Krittika Bibi, Sadia Bijani, Ali Bisignano, Catherine Bolarinwa, Obasanjo Afolabi Boloor, Archith Boltaev, Azizbek A. Briko, Nikolay Ivanovich Buonsenso, Danilo Burkart, Katrin Butt, Zahid A. Cao, Chao Charan, Jaykaran Chatterjee, Souranshu Chattu, Soosanna Kumary Chattu, Vijay Kumar Choudhari, Sonali Gajanan Chu, Dinh-Toi Couto, Rosa A.S. Cowden, Richard G. Dachew, Berihun Assefa Dadras, Omid Dagnew, Amare Belachew Dahlawi, Saad M.A. Dai, Xiaochen Dandona, Lalit Dandona, Rakhi das Neves, José Degenhardt, Louisa Demeke, Feleke Mekonnen Desta, Abebaw Alemayehu Deuba, Keshab Dhamnetiya, Deepak Dhungana, Govinda Prasad Dianatinasab, Mostafa Diaz, Daniel Djalalinia, Shirin Doan, Linh Phuong Dorostkar, Fariba Edinur, Hisham Atan Effiong, Andem Eftekharzadeh, Sahar El Sayed Zaki, Maysaa Elayedath, Rajesh Elhadi, Institute for Health Metrics and Evaluation University of Washington Seattle WA United States Department of Health Metrics Sciences School of Medicine University of Washington Seattle WA United States Division of Allergy and Infectious Diseases University of Washington Seattle WA United States Department of Global Health University of Washington Seattle WA United States School of Social Work University of Washington Seattle WA United States Department of Medicine University of Washington Seattle WA United States Vagelos College of Physicians and Surgeones Columbia University Medical Center New York NY United States Division of Data Analytics and Delivery for Impact WHO Geneva Switzerland Advanced Diagnostic and Interventional Radiology Research Centre Tehran University of Medical Sciences Tehran Iran Multiple Sclerosis Research Centre Tehran University of Medical Sciences Tehran Iran School of Public Health Tehran University of Medical Sciences Tehran Iran Department of Epidemiology and Biostatistics Tehran University of Medical Sciences Tehran Iran Paediatric Chronic Kidney Disease Research Centre Tehran University of Medical Sciences Tehran Iran Department of Psychiatry Tehran University of Medical Sciences Tehran Iran Metabolomics and Genomics Research Centre Tehran University of Medical Sciences Tehran Iran Sina Trauma and Surgery Research Centre Tehran University of Medical Sciences Tehran Iran Research Centre for Immunodeficiencies Tehran University of Medical Sciences Tehran Iran Non-Communicable Diseases Research Centre Tehran University of Medical Sciences Tehran Iran Department of Botany Sree Narayana Guru College Chelannur Kozhikode India Clinical Sciences Department University of Sharjah Sharjah United Arab Emirates Mass Communication Department University of Sharjah Sharjah United Arab Emirates Department of Health-Care Policy and Research Weill Cornell Medical College in Qatar Doha Qatar Department of Population Medicine Ca

Background: The sustainable development goals (SDGs) aim to end HIV/AIDS as a public health threat by 2030. Understanding the current state of the HIV epidemic and its change over time is essential to this effort. This study assesses the current sex-specific HIV burden in 204 countries and territories and measures progress in the control of the epidemic. Methods: To estimate age-specific and sex-specific trends in 48 of 204 countries, we extended the Estimation and Projection Package Age-Sex Model to also implement the spectrum paediatric model. We used this model in cases where age and sex specific HIV-seroprevalence surveys and antenatal care-clinic sentinel surveillance data were available. For the remaining 156 of 204 locations, we developed a cohort-incidence bias adjustment to derive incidence as a function of cause-of-death data from vital registration systems. The incidence was input to a custom Spectrum model. To assess progress, we measured the percentage change in incident cases and deaths between 2010 and 2019 (threshold >75% decline), the ratio of incident cases to number of people living with HIV (incidence-to-prevalence ratio threshold <0·03), and the ratio of incident cases to deaths (incidence-to-mortality ratio threshold <1·0). Findings: In 2019, there were 36·8 million (95% uncertainty interval [UI] 35·1–38·9) people living with HIV worldwide. There were 0·84 males (95% UI 0·78–0·91) per female living with HIV in 2019, 0·99 male infections (0·91–1·10) for every female infection, and 1·02 male deaths (0·95–1·10) per female death. Global progress in incident cases and deaths between 2010 and 2019 was driven by sub-Saharan Africa (with a 28·52% decrease in incident cases, 95% UI 19·58–35·43, and a 39·66% decrease in deaths, 36·49–42·36). Elsewhere, the incidence remained stable or increased, whereas deaths generally decreased. In 2019, the global incidence-to-prevalence ratio was 0·05 (95% UI 0·05–0·06) and the global incidence-to-mortality ratio was

关键词：

来源：评论

学校读者我要写书评

暂无评论

Quantum computing at the frontiers of biological sciences

arXiv

引用

arXiv 2019年

作者： Emani, Prashant S. Warrell, Jonathan Anticevic, Alan Bekiranov, Stefan Gandal, Michael McConnell, Michael J. Sapiro, Guillermo Aspuru-Guzik, Alán Baker, Justin Bastiani, Matteo McClure, Patrick Murray, John Sotiropoulos, Stamatios N. Taylor, Jacob Senthil, Geetha Lehner, Thomas Gerstein, Mark B. Harrow, Aram W. Program in Computational Biology and Bioinformatics Yale University New HavenCT06520 United States Department of Molecular Biophysics and Biochemistry Yale University New HavenCT06520 United States Yale School of Medicine Department of Psychiatry New HavenCT06511 United States University of Virginia School of Medicine Department of Biochemistry and Molecular Genetics CharlottesvilleVA22903 United States Department of Psychiatry Semel Institute David Geffen School of Medicine University of California–Los Angeles 695 Charles E. Young Drive South Los AngelesCA90095 United States Univ. of Virginia School of Medicine Department of Neuroscience CharlottesvilleVA22903 United States Department of Electrical and Computer Engineering Duke University DurhamNC27708 United States Department of Chemistry University of Toronto 80 St. George Street TorontoONM5S 3H6 Canada TorontoONM5S 1M1 Canada CIFAR Artificial Intelligence Research Chair Vector Institute TorontoONM5S 1M1 Canada Department of Computer Science University of Toronto 40 St. George Street TorontoONM5S 2E4 Canada Schizophrenia and Bipolar Disorder Program McLean Hospital BelmontMA02478 United States Department of Psychiatry Harvard Medical School BostonMA02114 United States Sir Peter Mansfield Imaging Centre School of Medicine University of Nottingham NottinghamNG7 2RD United Kingdom Machine Learning Team National Institute of Mental Health BethesdaMD20892 United States Section on Functional Imaging Methods National Institute of Mental Health BethesdaMD20892 United States Department of Psychiatry Yale University School of Medicine New HavenCT06511 United States Department of Physics Yale University New HavenCT06511 United States Joint Center for Quantum Information and Computer Science University of Maryland College ParkMD20742 United States National Institute of Standards and Technology GaithersburgMD20899 United States Office of Genomics Research Coordination N

The search for meaningful structure in biological data has relied on cutting-edge advances in computational technology and data science methods. However, challenges arise as we push the limits of scale and complexity in biological problems. Innovation in massively parallel, classical computing hardware and algorithms continues to address many of these challenges, but there is a need to simultaneously consider new paradigms to circumvent current barriers to processing speed. Accordingly, we articulate a view towards quantum computation and quantum information science, where algorithms have demonstrated potential polynomial and exponential computational speedups in certain applications, such as machine learning. The maturation of the field of quantum computing, in hardware and algorithm development, also coincides with the growth of several collaborative efforts to address questions across length and time scales, and scientific disciplines. We use this coincidence to explore the potential for quantum computing to aid in one such endeavor: the merging of insights from genetics, genomics, neuroimaging and behavioral phenotyping. By examining joint opportunities for computational innovation across fields, we highlight the need for a common language between biological data analysis and quantum computing. Ultimately, we consider current and future prospects for the employment of quantum computing algorithms in the biological sciences. Copyright © 2019, The Authors. All rights reserved.

关键词： Machine learning

来源：评论

学校读者我要写书评

暂无评论

Planck intermediate results. LVII. Joint Planck LFI and HFI data processing

arXiv

引用

arXiv 2020年

作者： Akrami, Y. Andersen, K.J. Ashdown, M. Baccigalupi, C. Ballardini, M. Banday, A.J. Barreiro, R.B. Bartolo, N. Basak, S. Benabed, K. Bernard, J.-P. Bersanelli, M. Bielewicz, P. Bond, J.R. Borrill, J. Burigana, C. Butler, R.C. Calabrese, E. Casaponsa, B. Chiang, H.C. Colombo, L.P.L. Combet, C. Crill, B.P. Cuttaia, F. de Bernardis, P. de Rosa, A. de Zotti, G. Delabrouille, J. Di Valentino, E. Diego, J.M. Doré, O. Douspis, M. Dupac, X. Eriksen, H.K. Fernandez-Cobos, R. Finelli, F. Frailis, M. Fraisse, A.A. Franceschi, E. Frolov, A. Galeotta, S. Galli, S. Ganga, K. Gerbino, M. Ghosh, T. González-Nuevo, J. Górski, K.M. Gruppuso, A. Gudmundsson, J.E. Handley, W. Helou, G. Herranz, D. Hildebrandt, S.R. Hivon, E. Huang, Z. Jaffe, A.H. Jones, W.C. Keihänen, E. Keskitalo, R. Kiiveri, K. Kim, J. Kisner, T.S. Krachmalnicoff, N. Kunz, M. Kurki-Suonio, H. Lasenby, A. Lattanzi, M. Lawrence, C.R. Le Jeune, M. Levrier, F. Liguori, M. Lilje, P.B. Lilley, M. Lindholm, V. López-Caniego, M. Lubin, P.M. Macías-Pérez, J.F. Maino, D. Mandolesi, N. Marcos-Caballero, A. Maris, M. Martin, P.G. Martínez-González, E. Matarrese, S. Mauri, N. McEwen, J.D. Meinhold, P.R. Mennella, A. Migliaccio, M. Mitra, S. Molinari, D. Montier, L. Morgante, G. Moss, A. Natoli, P. Paoletti, D. Partridge, B. Patanchon, G. Pearson, D. Pearson, T.J. Perrotta, F. Piacentini, F. Polenta, G. Rachen, J.P. Reinecke, M. Remazeilles, M. Renzi, A. Rocha, G. Rosset, C. Roudier, G. Rubiño-Martín, J.A. Ruiz-Granados, B. Salvati, L. Savelainen, M. Scott, D. Sirignano, C. Sirri, G. Spencer, L.D. Suur-Uski, A.-S. Svalheim, T.L. Tauber, J.A. Tavagnacco, D. Tenti, M. Terenzi, L. Thommesen, H. Toffolatti, L. Tomasi, M. Tristram, M. Trombetti, T. Valiviita, J. van Tent, B. Vielva, P. Villa, F. Vittorio, N. Wandelt, B.D. Wehus, I.K. Zacchei, A. Zonca, A. APC AstroParticule et Cosmologie Université Paris Diderot CNRS/IN2P3 CEA/lrfu Observatoire de Paris Sorbonne Paris Cité 10 rue Alice Domon et Léonie Duquet Paris Cedex 1375205 France African Institute for Mathematical Sciences 6-8 Melrose Road Muizenberg Cape Town South Africa Astrophysics Group Cavendish Laboratory University of Cambridge J J Thomson Avenue CambridgeCB3 0HE United Kingdom Astrophysics & Cosmology Research Unit School of Mathematics Statistics & Computer Science University of KwaZulu-Natal Westville Campus Private Bag X54001 Durban4000 South Africa CITA University of Toronto 60 St. George St. TorontoONM5S 3H8 Canada CNRS IRAP 9 Av. colonel Roche BP 44346 Toulouse cedex 4F-31028 France Cahill Center for Astronomy and Astrophysics California Institute of Technology PasadenaCA91125 United States California Institute of Technology PasadenaCA United States Computational Cosmology Center Lawrence Berkeley National Laboratory BerkeleyCA United States Département de Physique Théorique Université de Genève 24 Quai E. Ansermet Genève 41211 Switzerland Département de Physique École normale supérieure PSL Research University CNRS 24 rue Lhomond Paris75005 France La Laguna TenerifeE-38206 Spain Departamento de Física Universidad de Oviedo C/ Federico García Lorca 18 Oviedo Spain Department of Astrophysics IMAPP Radboud University P.O. Box 9010 Nijmegen6500 GL Netherlands Department of Physics & Astronomy University of British Columbia 6224 Agricultural Road VancouverBC Canada Department of Physics & Astronomy University of the Western Cape Cape Town7535 South Africa Department of Physics Gustaf Hällströmin katu 2a University of Helsinki Helsinki Finland Department of Physics Princeton University PrincetonNJ United States Department of Physics University of California Santa BarbaraCA United States Dipartimento di Fisica e Astronomia G. Galilei Università degli Studi di Padova via Marzolo 8 Padova35131 It

We present the NPIPE processing pipeline, which produces calibrated frequency maps in temperature and polarization from data from the Planck Low Frequency Instrument (LFI) and High Frequency Instrument (HFI) using high-performance computers. NPIPE represents a natural evolution of previous Planck analysis efforts, and combines some of the most powerful features of the separate LFI and HFI analysis pipelines. For example, following the LFI 2018 processing procedure, NPIPE uses foreground polarization priors during the calibration stage in order to break scanning-induced degeneracies. Similarly, NPIPE employs the HFI 2018 time-domain processing methodology to correct for bandpass mismatch at all frequencies. In addition, NPIPE introduces several improvements, including, but not limited to: inclusion of the 8 % of data collected during repointing manoeuvres;smoothing of the LFI reference load data streams;in-flight estimation of detector polarization parameters;and construction of maximally independent detector-set split maps. For component-separation purposes, important improvements include: maps that retain the CMB Solar dipole, allowing for high-precision relative calibration in higher-level analyses;well-defined single-detector maps, allowing for robust CO extraction;and HFI temperature maps between 217 and 857 GHz that are binned into 0.09 pixels (Nside = 4096), ensuring that the full angular information in the data is represented in the maps even at the highest Planck resolutions. The net effect of these improvements is lower levels of noise and systematics in both frequency and component maps at essentially all angular scales, as well as notably improved internal consistency between the various frequency channels. Based on the NPIPE maps, we present the first estimate of the Solar dipole determined through component separation across all nine Planck frequencies. The amplitude is (3366.6 ± 2.7) µK, consistent with, albeit slightly higher than, earlier estimates.

关键词： Cosmology

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：