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High-quality high-order harmonic generation through preplasma truncation

Physical Review E 2019年第5期100卷 053207-053207页

作者： B. Y. Li F. Liu M. Chen Z. Y. Chen X. H. Yuan S. M. Weng T. Jin S. G. Rykovanov J. W. Wang Z. M. Sheng J. Zhang Key Laboratory for Laser Plasmas (MoE) School of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240 China Collaborative Innovation Center of IFSA (CICIFSA) Shanghai Jiao Tong University Shanghai 200240 China National Key Laboratory of Shock Wave and Detonation Physics Institute of Fluid Physics China Academy of Engineering Physics Mianyang 621999 China Zhiyuan College Shanghai Jiao Tong University Shanghai 200240 China Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow 121205 Russia Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China Tsung-Dao Lee Institute Shanghai Jiao Tong University Shanghai 200240 China SUPA Department of Physics University of Strathclyde Glasgow G4 0NG United Kingdom

By introducing preplasma truncation to cases with an initial preplasma scale length larger than 0.2λ, the efficiency of high-order harmonics generated from relativistic laser-solid interactions can be enhanced by more than one order of magnitude and the angular spread can be confined into near-diffraction-limited divergence. Numerical simulations show that density truncation results in more compact oscillation of the surface electron sheet and the curvature of the reflection surface for the driving laser is greatly reduced. This leads to an overall improvement in the harmonic beam quality. More importantly, density truncation makes the harmonic generation weakly dependent on the preplasma scale length, which provides a way to relax the extremely high requirement on the temporal contrast of the driving laser pulse. A feasible scheme to realize the required preplasma truncation is also proposed and demonstrated by numerical simulations.

关键词： High intensity laser-plasma interactions High-order harmonic generation X-ray generation in plasmas

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Classical novae at radio wavelengths

arXiv

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arXiv 2021年

作者： Chomiuk, Laura Linford, Justin D. Aydi, Elias Bannister, Keith W. Krauss, Miriam I. Mioduszewski, Amy J. Mukai, Koji Nelson, Thomas J. Rupen, Michael P. Ryder, Stuart D. Sokoloski, Jennifer L. Sokolovsky, Kirill V. Strader, Jay Filipović, Miroslav D. Finzell, Tom Kawash, Adam Kool, Erik C. Metzger, Brian D. Nyamai, Miriam M. Ribeiro, Valério A.R.M. Roy, Nirupam Urquhart, Ryan Weston, Jennifer Center for Data Intensive and Time Domain Astronomy Department of Physics and Astronomy Michigan State University East LansingMI48824 United States National Radio Astronomy Observatory P.O. Box O SocorroNM87801 United States CSIRO Astronomy and Space Science PO Box 76 EppingNSW1710 Australia Pasadena City College 1570 E. Colorado Blvd. PasadenaCA91106 United States Center for Space Science and Technology University of Maryland Baltimore County BaltimoreMD21250 United States CRESST and X-ray Astrophysics Laboratory NASA/GSFC GreenbeltMD20771 United States Department of Physics and Astronomy University of Pittsburgh 3941 OHara St. PittsburghPA15260 United States Herzberg Institute of Astrophysics National Research Council of Canada PentictonBCV2A 6J9 Canada Department of Physics and Astronomy Macquarie University NSW2109 Australia Macquarie University Research Centre for Astronomy Astrophysics & Astrophotonics SydneyNSW2109 Australia Columbia Astrophysics Laboratory Columbia University New YorkNY United States Sternberg Astronomical Institute Moscow State University Universitetskii pr. 13 Moscow119992 Russia Western Sydney University Locked Bag 1797 Penrith South DCNSW2751 Australia Department of Computational Math Science and Engineering Michigan State University East LansingMI48824 United States The Oskar Klein Centre Department of Astronomy Stockholm University AlbaNova StockholmSE-106 91 Sweden Center for Computational Astrophysics Flatiron Institute 162 W. 5th Avenue New YorkNY10011 United States Department of Astronomy University of Cape Town Private Bag X3 Rondebosch7701 South Africa Instituto de Telecomunicações Campus Universitário de Santiago Aveiro3810-193 Portugal Department of Physics Indian Institute of Science Bangalore560012 India Federated IT 1201 Wilson Blvd 27th Floor ArlingtonVA22209 United States

We present radio observations (1–40 GHz) for 36 classical novae, representing data from over five decades compiled from the literature, telescope archives, and our own programs. Our targets display a striking diversity in their optical parameters (e.g., spanning optical fading timescales, t2 = 1–263 days), and we find a similar diversity in the radio light curves. Using a brightness temperature analysis, we find that radio emission from novae is a mixture of thermal and synchrotron emission, with non-thermal emission observed at earlier times. We identify high brightness temperature emission (TB > 5 × 104 K) as an indication of synchrotron emission in at least 9 (25%) of the novae. We find a class of synchrotron-dominated novae with mildly evolved companions, exemplified by V5589 Sgr and V392 Per, that appear to be a bridge between classical novae with dwarf companions and symbiotic binaries with giant companions. Four of the novae in our sample have two distinct radio maxima (the first dominated by synchrotron and the later by thermal emission), and in four cases the early synchrotron peak is temporally coincident with a dramatic dip in the optical light curve, hinting at a common site for particle acceleration and dust formation. We publish the light curves as tables and encourage use of these data by the broader community in multi-wavelength studies and modeling efforts. © 2021, CC BY.

关键词： Radio astronomy

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Streams, Shells, and Substructures in the Accretion-Built Stellar Halo of NGC 300

arXiv

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arXiv 2025年

作者： Fielder, Catherine E. Sand, David J. Jones, Michael G. Crnojević, Denija Drlica-Wagner, Alex Bennet, Paul Carlin, Jeffrey L. Cerny, William Doliva-Dolinsky, Amandine Hunter, Laura C. Karunakaran, Ananthan Limberg, Guilherme Mutlu-Pakdil, Burçin Pace, Andrew B. Pearson, Sarah Smercina, Adam Spekkens, Kristine Starkenburg, Tjitske Strader, Jay Stringfellow, Guy S. Tollerud, Erik Bom, Clecio R. Carballo-Bello, Julio A. Chaturvedi, Astha Choi, Yumi James, David J. Martínez-Vázquez, Clara E. Riley, Alex Sakowska, Joanna Vivas, Kathy Steward Observatory University of Arizona 933 North Cherry Avenue TucsonAZ85721-0065 United States Department of Physics and Astronomy University of Tampa 401 West Kennedy Boulevard TampaFL33606 United States Astronomy & Astrophysics University of Chicago ChicagoIL60637 United States Fermi National Accelerator Laboratory BataviaIL United States Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States AURA/Rubin Observatory 950 North Cherry Avenue TucsonAZ85719 United States Department of Astronomy Yale University New HavenCT06520 United States Department of Physics and Astronomy Dartmouth College HanoverNH03755 United States Department of Astronomy & Astrophysics University of Toronto TorontoONM5S 3H4 Canada Dunlap Institute for Astronomy and Astrophysics University of Toronto TorontoONM5S 3H4 Canada Kavli Institute for Cosmological Physics University of Chicago ChicagoIL60637 United States Department of Astronomy University of Virginia 530 McCormick Rd CharlottesvilleVA22904 United States Niels Bohr Institute University of Copenhagen Copenhagen Denmark Department of Physics and Space Science Royal Military College of Canada P.O. Box 17000 Station Forces KingstonONK7K 7B4 Canada Department of Physics Engineering Physics and Astronomy Queen's University KingstonONK7L 3N6 Canada Department of Physics & Astronomy CIERA Northwestern University EvanstonIL United States Center for Data Intensive and Time Domain Astronomy Department of Physics and Astronomy Michigan State University East LansingMI48824 United States Center for Astrophysics and Space Astronomy University of Colorado 389 UCB BoulderCO80309-0389 United States Centro Brasileiro de Pesquisas Fisicas Rua Dr. Xavier Sigaud 150 RJ Rio de Janeiro22290-180 Brazil Instituto de Alta Investigación Universidad de Tarapacá Casilla 7D Arica Chile Department of Physics University of Surrey GuildfordGU2 7XH United Kingdom NSF NOIRLab 95

We present deep optical observations of the stellar halo of NGC 300, an LMC-mass galaxy, acquired with the DEEP sub-component of the DECam Local Volume Exploration survey (DELVE) using the 4 m Blanco Telescope. Our resolved star analysis reveals a large, low surface brightness stellar stream (MV ∼ -8.5;[Fe/H] = -1.4± 0.15) extending more than 40 kpc north from the galaxy's center. We also find other halo structures, including potentially an additional stream wrap to the south, which may be associated with the main stream. The morphology and derived low metallicities of the streams and shells discovered surrounding NGC 300 are highly suggestive of a past accretion event. Assuming a single progenitor, the accreted system is approximately Fornax-like in luminosity, with an inferred mass ratio to NGC 300 of approximately 1 : 15. We also present the discovery of a metal-poor globular cluster (Rproj = 23.3 kpc;MV = -8.99± 0.16;[Fe/H] ≈ -1.6± 0.6) in the halo of NGC 300, the furthest identified globular cluster associated with NGC 300. The stellar structures around NGC 300 represent the richest features observed in a Magellanic Cloud analog to date, strongly supporting the idea that accretion and subsequent disruption is an important mechanism in the assembly of dwarf galaxy stellar halos. © 2025, CC BY-SA.

关键词： Stars

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Author Correction: Natural Erosion of Sandstone as Shape Optimisation

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Scientific reports 2018年第1期8卷 6232页

作者： Igor Ostanin Alexander Safonov Ivan Oseledets Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow Russia. i.ostanin@skoltech.ru. Center for Design Manufacturing and Materials Skolkovo Institute of Science and Technology Moscow Russia. Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow Russia.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

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QTT-isogeometric solver in two dimensions

arXiv

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arXiv 2018年

作者： Markeeva, L. Tsybulin, I. Oseledets, I. Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow Russia Department of Applied Math and Control Moscow Institute of Physics and Technology Moscow Russia Laboratory of Fluid Dynamics and Seismics Moscow Institute of Physics and Technology Moscow Russia Institute of Numerical Mathematics Russian Academy of Sciences Moscow Russia

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Field heterogeneity detection based on the modified FastICA RGB-image processing

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Journal of Physics: Conference Series 2018年第1期1117卷

作者： L Mirvakhabova M Pukalchik S Matveev P Tregubova I Oseledets Skoltech Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology 1 Nobel Street Moscow 121205 Russia Marchuk Institute of Numerical Mathematics RAS 8 Gubkin Street 119333 Moscow Russia

In the light of the increasing demand for food production, climate change challenges, and economic pressure, precision farming is becoming an ever-growing market. Nowadays using satellite images for field zoning has become a widely spread technique employed in precision agriculture. Usually satellite images are used to evaluate Normalized Difference Vegetation Index (NDVI) as a common yield assessment. At the same time it is rather a challenging task to designing NDVI maps as compared to ordinary RGB images. We propose a new algorithm for site-specific zoning based on the performance of a well-known and widely used ICA algorithm (FastICA). We analyse high resolution RGB satellite images for 3 arable fields located in Kursk region, Russia, (2017) provided by the Planet Labs service. The main outcomes from this study are (i) the algorithm creates site-specific zoning maps with a relative accuracy of yield distribution maps between 0.78 and 0.89; (ii) the algorithm requires a relatively small dataset – from 8 to 10 RGB images. The obtained results indicate that the algorithm in question can be used not only to identify management zones but also to map the variations in yield within the fields.

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APOGEE-centric Ananke Simulations in a SciServer SQL database

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Research Notes of the AAS 2022年第6期6卷 125-125页

作者： Rachael L. Beaton Suzanne Werner Arik W. Mitschang Gerard Lemson Aniruddha Thakar Anne-Marie Weijmans Joel R. Brownstein Farnik Nikakhtar Robyn E. Sanderson Andrew Wetzel Sarah Loebman Sanjib Sharma Space Telescope Science Institute 3700 San Martin Drive Baltimore MD 21218 USA rbeaton@princeton.edu Department of Astrophysical Sciences Princeton University 4 Ivy Lane Princeton NJ 08544 USA The Observatories of the Carnegie Institution for Science 813 Santa Barbara St. Pasadena CA 91101 USA Institute For Data Intensive Engineering and Science Johns Hopkins University. 3701 San Martin Drive Baltimore MD 21218 USA Center for Astrophysical Sciences Department of Physics and Astronomy Johns Hopkins University 3400 North Charles Street Baltimore MD 21218 USA School of Physics and Astronomy University of St Andrews North Haugh St Andrews KY16 9SS UK Department of Physics and Astronomy University of Utah 115 S. 1400 E. Salt Lake City UT 84112 USA Department of Physics & Astronomy University of Pennsylvania 209 S 33rd St. Philadelphia PA 19104 USA Center for Computational Astrophysics Flatiron Institute 162 5th Ave New York NY 10010 USA Department of Physics & Astronomy University of California Davis CA 95616 USA Department of Physics University of California Merced 5200 North Lake Rd. Merced CA 95343 USA Sydney Institute for Astronomy School of Physics A28 The University of Sydney NSW 2006 Australia Center of Excellence for Astrophysics in Three Dimensions (ASTRO-3D) Australia

Modern galaxy simulations have reached the complexity required to create sophisticated mock catalogs. Ananke is a set of nine mock catalogs constructed from synthetic surveys of three Milky Way-like galaxies from the Latte suite of FIRE simulations. Ananke provides observed quantities for comparison with modern large-scale stellar surveys. In SDSS-IV DR17, mock catalogs for the Apache Point Galactic Evolution Experiment (APOGEE) were built from Ananke synthetic surveys as a Value-Added Catalog, but were only provided as large flat files (∼>10's GB). Here we announce an >40 Tb SQL database for nine APOGEE-specific mock catalogs and describe additions to the data model necessary for effective user queries. The catalogs can be accessed on the free, science platform, SciServer—supported by the Institute for data intensive engineering and science at the Johns Hopkins University (IDIES); SciServer supports server-side analysis with commonly used coding languages and tools.

关键词： Catalogs Milky Way Galaxy Surveys Redshift surveys Astronomy databases

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The TESS-Keck Survey XXI: 13 New Planets and Homogeneous Properties for 21 Subgiant Systems

arXiv

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arXiv 2024年

作者： Chontos, Ashley Huber, Daniel Grunblatt, Samuel K. Saunders, Nicholas Winn, Joshua N. McCormack, Mason Knudstrup, Emil Albrecht, Simon H. Crossfield, Ian J.M. Rodriguez, Joseph E. Ciardi, David R. Collins, Karen A. Jenkins, Jon M. Bieryla, Allyson Batalha, Natalie M. Beard, Corey Dai, Fei Dalba, Paul A. Fetherolf, Tara Giacalone, Steven Hill, Michelle L. Howard, Andrew W. Isaacson, Howard Kane, Stephen R. Lubin, Jack Macdougall, Mason G. Močnik, Teo Akana Murphy, Joseph M. Petigura, Erik A. Pidhorodetska, Daria Polanski, Alex S. Robertson, Paul Rubenzahl, Ryan A. Turtelboom, Emma V. Weiss, Lauren M. van Zandt, Judah Ricker, George R. Vanderspek, Roland Latham, David W. Seager, Sara Quinn, Samuel N. Shporer, Avi Eisner, Nora L. Goeke, Robert F. Levine, Alan M. Ting, Eric B. Howell, Steve Schlieder, Joshua E. Benni, Paul Boyle, Andrew W. Gan, Tianjun Girardin, Eric Gonzalez, Erica Gregorio, Joao Horne, Keith Livingston, John Lund, Michael B. Mann, Christopher R. Massey, Bob Matthews, Elisabeth C. McLeod, Kim K. Palle, Enric Popowicz, Adam Relles, Howard M. Schwarz, Richard P. Sefako, Ramotholo Srdoc, Gregor Tan, Thiam-Guan Wang, Gavin Ziegler, Carl Institute for Astronomy University of Hawai'i 2680 Woodlawn Drive HonoluluHI96822 United States Department of Astrophysical Sciences Princeton University 4 Ivy Lane PrincetonNJ08544 United States School of Physics University of Sydney NSW2006 Australia Department of Physics and Astronomy Johns Hopkins University 3400 N Charles St BaltimoreMD21218 United States Department of Astronomy & Astrophysics University of Chicago ChicagoIL60637 United States Department of Space Earth and Environment Chalmers University of Technology Gothenburg412 93 Sweden Stellar Astrophysics Centre Department of Physics and Astronomy Aarhus University Ny Munkegade 120 Aarhus CDK-8000 Denmark Department of Physics & Astronomy University of Kansas 1251 Wescoe Hall Dr. 1082 Malott LawrenceKS66045 United States Center for Data Intensive and Time Domain Astronomy Department of Physics and Astronomy Michigan State University East LansingMI48824 United States Caltech/IPAC-NASA Exoplanet Science Institute 770 S. Wilson Avenue PasadenaCA91106 United States Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States NASA Ames Research Center Moffett FieldCA94035 United States Department of Astronomy and Astrophysics University of California Santa CruzCA95060 United States Department of Physics & Astronomy University of California Irvine IrvineCA92697 United States Division of Geological and Planetary Sciences 1200 E California Blvd PasadenaCA91125 United States Department of Astronomy California Institute of Technology PasadenaCA91125 United States Department of Astronomy and Astrophysics University of California Santa CruzCA95064 United States Department of Physics California State University San MarcosCA92096 United States Department of Earth and Planetary Sciences University of California RiversideCA92521 United States Department of Astronomy University of California Berkeley BerkeleyCA94720 United States

We present a dedicated transit and radial velocity survey of planets orbiting subgiant stars observed by the TESS Mission. Using ∼16 nights on Keck/HIRES, we confirm and characterize 12 new transiting planets - TOI-329 b, HD 39688 b (TOI-480), TOI-603 b, TOI-1199 b, TOI-1294 b, TOI-1439 b, TOI-1605 b, TOI-1828 b, HD 148193 b (TOI-1836), TOI-1885 b, HD 83342 b (TOI-1898), TOI-2019 b - and provide updated properties for 9 previously confirmed TESS subgiant systems (TOI-197, TOI-954, TOI-1181, TOI-1296, TOI-1298, TOI-1601, TOI-1736, TOI-1842, TOI-2145). We also report the discovery of an outer, non-transiting planet, TOI-1294 (Equation presented) and three additional stars with long-term RV trends. We find that at least 19±8% of subgiants in our sample of 21 stars have outer companions, comparable to main-sequence stars. We perform a homogeneous analysis of the stars and planets in the sample, with median uncertainties of 3%, 8% and 15% for planet radii, masses and ages, doubling the number of known planets orbiting subgiant stars with bulk densities measured to better than 10%. We observe a dearth of giant planets around evolved stars with short orbital periods, consistent with tidal dissipation theories that predict the rapid inspiral of planets as their host stars leave the main sequence. We note the possible evidence for two distinct classes of hot Jupiter populations, indicating multiple formation channels to explain the observed distributions around evolved stars. Finally, continued RV monitoring of planets in this sample will provide a more comprehensive understanding of demographics for evolved planetary systems. © 2024, CC BY.

关键词： Planets

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Corrigendum to “Single-walled carbon nanotube membranes for optical applications in the extreme ultraviolet rang” [155, (2019) 734–739]

引用

Carbon 2020年 156卷 576-576页

作者： V.M. Gubarev V.Y. Yakovlev M.G. Sertsu O.F. Yakushev V.M. Krivtsun Yu G. Gladush I.A. Ostanin A. Sokolov F. Schäfers V.V. Medvedev A.G. Nasibulin Moscow Institute of Physics and Technology (State University) Institutskiy pereulok str. 9 Dolgoprudny Moscow Region 141701 Russia Skolkovo Institute of Science and Technology Nobel str. 3 Moscow 121205 Russia Helmholtz Zentrum Berlin (BESSY-II) Albert-Einstein-Strasse 15 D-12489 Berlin Germany P. N. Lebedev Physical Institute of the Russian Academy of Science Moscow Russia Institute for Spectroscopy of the Russian Academy of Science Moscow Troitsk Russia Faculty of Physics Higher School of Economics Old Basmannya 21/4 Moscow Russia Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow Russia Multi-Scale Mechanics (MSM) Faculty of Engineering Technology MESA+ University of Twente Enschede the Netherlands Department of Applied Physics Aalto University 15100 FI-00076 Aalto Finland

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AA-ICP: Iterative closest point with anderson acceleration

arXiv

引用

arXiv 2017年

作者： Pavlov, A.L. Ovchinnikov, G.V. Derbyshev, D.Yu. Tsetserukou, D. Oseledets, I.V. Space Center Skolkovo Institute of Science and Technology Skolkovo Innovation Center Moscow143026 Russia Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow Institute of Physics and Technology Space Center Skolkovo Institute of Science and Technology

Iterative Closest Point (ICP) is a widely used method for performing scan-matching and registration. Being simple and robust method, it is still computationally expensive and may be challenging to use in real-time applications with limited resources on mobile platforms. In this paper we propose novel effective method for acceleration of ICP which does not require substantial modifications to the existing code. This method is based on an idea of Anderson acceleration which is an iterative procedure for finding a fixed point of contractive mapping. The latter is often faster than a standard Picard iteration, usually used in ICP implementations. We show that ICP, being a fixed point problem, can be significantly accelerated by this method enhanced by heuristics to improve overall robustness. We implement proposed approach into Point Cloud Library (PCL) and make it available online. Benchmarking on real-world data fully supports our claims. Copyright © 2017, The Authors. All rights reserved.

关键词： Heuristic methods

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