arXiv: Instrumentation and Methods for Astrophysics最新文献

{"title":"Frontiers in Planetary Rings Science","authors":"S. Brooks, T. Becker, K. Bailli'e, H. Becker, E. T. Bradley, J. Colwell, J. Cuzzi, I. Pater, S. Eckert, M. E. Moutamid, S. Edgington, P. Estrada, M. Evans, A. Flandes, R. French, 'A. Garc'ia, M. Gordon, M. Hedman, H. Hsu, R. Jerousek, E. Marouf, B. Meinke, P. Nicholson, S. Pilorz, M. Showalter, L. Spilker, H. Throop, M. Tiscareno","doi":"10.3847/25C2CFEB.7BF80D38","DOIUrl":"https://doi.org/10.3847/25C2CFEB.7BF80D38","url":null,"abstract":"We now know that the outer solar system is host to at least six diverse planetary ring systems, each of which is a scientifically compelling target with the potential to inform us about the evolution, history and even the internal structure of the body it adorns. These diverse ring systems represent a set of distinct local laboratories for understanding the physics and dynamics of planetary disks, with applications reaching beyond our Solar System. We highlight the current status of planetary rings science and the open questions before the community to promote continued Earth-based and spacecraft-based investigations into planetary rings. As future spacecraft missions are launched and more powerful telescopes come online in the decades to come, we urge NASA for continued support of investigations that advance our understanding of planetary rings, through research and analysis of data from existing facilities, more laboratory work and specific attention to strong rings science goals during future mission selections.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90213892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Array of Long Baseline Antennas for Taking Radio Observations from the Sub-Antarctic","authors":"H. Chiang, T. Dyson, E. Egan, S. Eyono, N. Ghazi, J. Hickish, J. Jáuregui-García, V. Manukha, T. Menard, T. Moso, J. Peterson, L. Philip, J. Sievers, S. Tartakovsky","doi":"10.1142/s2251171720500191","DOIUrl":"https://doi.org/10.1142/s2251171720500191","url":null,"abstract":"Measurements of redshifted 21-cm emission of neutral hydrogen at <30 MHz have the potential to probe the cosmic \"dark ages,\" a period of the universe's history that remains unobserved to date. Observations at these frequencies are exceptionally challenging because of bright Galactic foregrounds, ionospheric contamination, and terrestrial radio-frequency interference. Very few sky maps exist at <30 MHz, and most have modest resolution. We introduce the Array of Long Baseline Antennas for Taking Radio Observations from the Sub-Antarctic (ALBATROS), a new experiment that aims to image low-frequency Galactic emission with an order-of-magnitude improvement in resolution over existing data. The ALBATROS array will consist of antenna stations that operate autonomously, each recording baseband data that will be interferometrically combined offline. The array will be installed on Marion Island and will ultimately comprise 10 stations, with an operating frequency range of 1.2-125 MHz and maximum baseline lengths of ~20 km. We present the ALBATROS instrument design and discuss pathfinder observations that were taken from Marion Island during 2018-2019.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"79 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90569650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observing the Polarized Cosmic Microwave Background From the Earth: Scanning Strategy and Polarimeters Test for the Lspe/strip Instrument","authors":"F. Incardona","doi":"10.13130/incardona-federico_phd2020-01-17","DOIUrl":"https://doi.org/10.13130/incardona-federico_phd2020-01-17","url":null,"abstract":"Detecting B-mode polarization anisotropies on large angular scales in the CMB polarization pattern is one of the major challenges in modern observational cosmology since it would give us an important evidence in favor of the inflationary paradigm and would shed light on the physics of the very early Universe. Multi-frequency observations are required to disentangle the very weak CMB signal from diffuse polarized foregrounds originating by radiative processes in our galaxy. The \"Large Scale Polarization Explorer\" (LSPE) is an experiment that aims to constrain the ratio between the amplitudes of tensor and scalar modes and to study the polarized emission of the Milky Way. LSPE is composed of two instruments: SWIPE, a stratospheric balloon operating at 140, 210 and 240 GHz that will fly for two weeks in the Northern Hemisphere during the polar night of 2021, and STRIP, a ground-based telescope that will start to take data in early 2021 from the \"Observatorio del Teide\" in Tenerife observing the sky at 43 GHz and 95 GHz. In my thesis, I show the results of the unit-level tests campaign on the STRIP detectors that took place at \"Universit`a degli Studi di Milano Bicocca\" from September 2017 to July 2018, and I present the code I developed and the simulations I performed to study the STRIP scanning strategy. During the unit-level tests, more than 800 tests on 68 polarimeters have been performed in order to select the 55 with the best performance in terms of central frequencies, bandwidths, noise temperatures, white noise levels, slopes and knee frequencies. The STRIP scanning strategy is based on spinning the telescope around the azimuth axis with constant elevation in order to overlap the SWIPE coverage maintaining a sensitivity of 1.6 {mu}K (on average) per sky pixels of 1{deg}. Individual sources will be periodically observed both for calibration and study purposes.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"90 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91042211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Demonstration of an amplitude filter cavity at gravitational-wave frequencies","authors":"K. Komori, D. Ganapathy, C. Whittle, L. McCuller, L. Barsotti, N. Mavalvala, M. Evans","doi":"10.1103/physrevd.102.102003","DOIUrl":"https://doi.org/10.1103/physrevd.102.102003","url":null,"abstract":"Quantum vacuum fluctuations fundamentally limit the precision of optical measurements, such as those in gravitational-wave detectors. Injection of conventional squeezed vacuum can be used to reduce quantum noise in the readout quadrature, but this reduction is at the cost of increasing noise in the orthogonal quadrature. For detectors near the limits imposed by quantum radiation pressure noise (QRPN), both quadratures impact the measurement, and the benefits of conventional squeezing are limited. In this paper, we demonstrate the use of a critically-coupled 16m optical cavity to diminish anti-squeezing at frequencies below 90Hz where it exacerbates QRPN, while preserving beneficial squeezing at higher frequencies. This is called an amplitude filter cavity, and it is useful for avoiding degradation of detector sensitivity at low frequencies. The attenuation from the cavity also provides technical advantages such as mitigating backscatter.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72754267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The science enabled by a dedicated solar system space telescope","authors":"C. Young, M. Wong, K. Sayanagi, S. Curry, K. Jessup, T. Becker, A. Hendrix, N. Chanover, S. Milam, B. Holler, G. Holsclaw, J. Peralta, J. Clarke, J. Spencer, M. Kelley, J. Luhmann, D. MacDonnell, R. Vervack, K. Retherford, L. Fletcher, I. Pater, F. Vilas, L. Feaga, O. Siegmund, J. Bell, G. Delory, J. Pitman, T. Greathouse, E. Wishnow, N. Schneider, R. Lillis, J. Colwell, L. Bowman, Rosaly M. C. Lopes, M. McGrath, F. Marchis, R. Cartwright, M. Poston","doi":"10.3847/25C2CFEB.B59267F2","DOIUrl":"https://doi.org/10.3847/25C2CFEB.B59267F2","url":null,"abstract":"The National Academy Committee on Astrobiology and Planetary Science (CAPS) made a recommendation to study a large/medium-class dedicated space telescope for planetary science, going beyond the Discovery-class dedicated planetary space telescope endorsed in Visions and Voyages. Such a telescope would observe targets across the entire solar system, engaging a broad spectrum of the science community. It would ensure that the high-resolution, high-sensitivity observations of the solar system in visible and UV wavelengths revolutionized by the Hubble Space Telescope (HST) could be extended. A dedicated telescope for solar system science would: (a) transform our understanding of time-dependent phenomena in our solar system that cannot be studied currently under programs to observe and visit new targets and (b) enable a comprehensive survey and spectral characterization of minor bodies across the solar system, which requires a large time allocation not supported by existing facilities. The time-domain phenomena to be explored are critically reliant on high spatial resolution UV-visible observations. This paper presents science themes and key questions that require a long-lasting space telescope dedicated to planetary science that can capture high-quality, consistent data at the required cadences that are free from effects of the terrestrial atmosphere and differences across observing facilities. Such a telescope would have excellent synergy with astrophysical facilities by placing planetary discoveries made by astrophysics assets in temporal context, as well as triggering detailed follow-up observations using larger telescopes. The telescope would support future missions to the Ice Giants, Ocean Worlds, and minor bodies across the solar system by placing the results of such targeted missions in the context of longer records of temporal activities and larger sample populations.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86464439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maximizing the Value of Solar System Data Through Planetary Spatial Data Infrastructures","authors":"J. Radebaugh, B. Thomson, B. Archinal, R. Beyer, D. DellaGiustina, C. Fassett, L. Gaddis, S. Goossens, T. Hare, J. Laura, P. Mouginis-Mark, A. Nass, A. Patthoff, J. Stopar, S. Sutton, D. Williams, J. Hagerty, Louise Prockter Brigham Young University, Provo, Ut, Usa, U. Tennessee, Knoxville, Tn, Astrogeology Science Center, U. S. G. Survey, Flagstaff, Az, S. Institute, N. Ames, Mountain View, Ca, University of Arizona Lunar, Planetary Laboratory, Tucson, Nasa Goddard Space Flight Center, Huntsville, Al., Nasa Goddard Space Flight Center, Greenbelt, Md., S. O. O. ScienceTechnology, U. Hawaii, Honolulu, Hi, Deutsche Forschungsanstalt für Luft und Raumfahrt, H Germany, P. Institute, Lunar, P. Institute, Universities Space Research Association, Houston, Tx, School of Earth, Space Exploration, A. S. University, Tempe","doi":"10.3847/25C2CFEB.02596661","DOIUrl":"https://doi.org/10.3847/25C2CFEB.02596661","url":null,"abstract":"Planetary spatial data returned by spacecraft, including images and higher-order products such as mosaics, controlled basemaps, and digital elevation models (DEMs), are of critical importance to NASA, its commercial partners and other space agencies. Planetary spatial data are an essential component of basic scientific research and sustained planetary exploration and operations. The Planetary Data System (PDS) is performing the essential job of archiving and serving these data, mostly in raw or calibrated form, with less support for higher-order, more ready-to-use products. However, many planetary spatial data remain not readily accessible to and/or usable by the general science user because particular skills and tools are necessary to process and interpret them from the raw initial state. There is a critical need for planetary spatial data to be more accessible and usable to researchers and stakeholders. A Planetary Spatial Data Infrastructure (PSDI) is a collection of data, tools, standards, policies, and the people that use and engage with them. A PSDI comprises an overarching support system for planetary spatial data. PSDIs (1) establish effective plans for data acquisition; (2) create and make available higher-order products; and (3) consider long-term planning for correct data acquisition, processing and serving (including funding). We recommend that Planetary Spatial Data Infrastructures be created for all bodies and key regions in the Solar System. NASA, with guidance from the planetary science community, should follow established data format standards to build foundational and framework products and use those to build and apply PDSIs to all bodies. Establishment of PSDIs is critical in the coming decade for several locations under active or imminent exploration, and for all others for future planning and current scientific analysis.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"50 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91497778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal extraction of echelle spectra: Getting the most out of observations","authors":"N. Piskunov, A. Wehrhahn, T. Marquart","doi":"10.1051/0004-6361/202038293","DOIUrl":"https://doi.org/10.1051/0004-6361/202038293","url":null,"abstract":"The price of instruments and observing time on modern telescopes is quickly increasing with the size of the primary mirror. Therefore, it is worth revisiting the data reduction algorithms to extract every bit of scientific information from observations. Echelle spectrographs are typical instruments in high-resolution spectroscopy, but attempts to improve the wavelength coverage and versatility of these instruments results in a complicated and variable footprint of the entrance slit projection onto the science detector. Traditional spectral extraction methods fail to perform a truly optimal extraction, when the slit image is not aligned with the detector columns but instead is tilted or even curved. \u0000We here present the mathematical algorithms and examples of their application to the optimal extraction and the following reduction steps for echelle spectrometers equipped with an entrance slit, that is imaged with various distortions, such as variable tilt and curvature. The new method minimizes the loss of spectral resolution, maximizes the signal-to-noise ratio, and efficiently identifies local outliers. In addition to the new optimal extraction we present order splicing and a more robust continuum normalization algorithms. \u0000We have developed and implemented new algorithms that create a continuum-normalized spectrum. In the process we account for the (variable) tilt/curvature of the slit image on the detector and achieve optimal extraction without prior assumptions about the slit illumination. Thus the new method can handle arbitrary image slicers, slit scanning, and other observational techniques aimed at increasing the throughput or dynamic range. \u0000We compare our methods with other techniques for different instruments to illustrate superior performance of the new algorithms compared to commonly used procedures.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"77 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80856953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Science Case for a Titan Flagship-class Orbiter with Probes","authors":"C. Nixon, J. Abshire, A. Ashton, J. Barnes, N. Carrasco, M. Choukroun, A. Coustenis, L. Couston, N. Edberg, A. Gagnon, J. Hofgartner, L. Iess, S. L. Mou'elic, Rosaly M. C. Lopes, J. Lora, R. Lorenz, A. Luspay-Kuti, M. Malaska, K. Mandt, M. Mastrogiuseppe, E. Mazarico, M. Neveu, T. Perron, J. Radebaugh, S. Rodriguez, Farid Salama, A. Schoenfeld, J. Soderblom, A. Solomonidou, D. Snowden, X. Sun, N. Teanby, G. Tobie, M. Trainer, O. Tucker, E. Turtle, S. Vinatier, V. Vuitton, Xi Zhang","doi":"10.3847/25C2CFEB.BC2B9583","DOIUrl":"https://doi.org/10.3847/25C2CFEB.BC2B9583","url":null,"abstract":"We outline a flagship-class mission concept focused on studying Titan as a global system, with particular emphasis on the polar regions. Investigating Titan from the unique standpoint of a polar orbit would enable comprehensive global maps to uncover the physics and chemistry of the atmosphere, and the topography and geophysical environment of the surface and subsurface. The mission includes two key elements: (1) an orbiter spacecraft, which also acts as a data relay, and (2) one or more small probes to directly investigate Titan's seas and make the first direct measurements of their liquid composition and physical environment. The orbiter would carry a sophisticated remote sensing payload, including a novel topographic lidar, a long-wavelength surface-penetrating radar, a sub-millimeter sounder for winds and for mesospheric/thermospheric composition, and a camera and near-infrared spectrometer. An instrument suite to analyze particles and fields would include a mass spectrometer to focus on the interactions between Titan's escaping upper atmosphere and the solar wind and Saturnian magnetosphere. The orbiter would enter a stable polar orbit around 1500 to 1800 km, from which vantage point it would make global maps of the atmosphere and surface. One or more probes, released from the orbiter, would investigate Titan's seas in situ, including possible differences in composition between higher and lower latitude seas, as well as the atmosphere during the parachute descent. The number of probes, as well as the instrument complement on the orbiter and probe, remain to be finalized during a mission study that we recommend to NASA as part of the NRC Decadal Survey for Planetary Science now underway, with the goal of an overall mission cost in the \"small flagship\" category of ~$2 bn. International partnerships, similar to Cassini-Huygens, may also be included for consideration.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"80 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79046642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constraining prebiotic chemistry through a better understanding of Earth’s earliest environments","authors":"T. Lyons, K. Rogers, R. Krishnamurthy, L. Williams, S. Marchi, E. Schwieterman, N. Planavsky, C. Reinhard","doi":"10.3847/25C2CFEB.7A898B78","DOIUrl":"https://doi.org/10.3847/25C2CFEB.7A898B78","url":null,"abstract":"Any search for present or past life beyond Earth should consider the initial processes and related environmental controls that might have led to its start. As on Earth, such an understanding lies well beyond how simple organic molecules become the more complex biomolecules of life, because it must also include the key environmental factors that permitted, modulated, and most critically facilitated the prebiotic pathways to life's emergence. Moreover, we ask how habitability, defined in part by the presence of liquid water, was sustained so that life could persist and evolve to the point of shaping its own environment. Researchers have successfully explored many chapters of Earth's coevolving environments and biosphere spanning the last few billion years through lenses of sophisticated analytical and computational techniques, and the findings have profoundly impacted the search for life beyond Earth. Yet life's very beginnings during the first hundreds of millions of years of our planet's history remain largely unknown--despite decades of research. This report centers on one key point: that the earliest steps on the path to life's emergence on Earth were tied intimately to the evolving chemical and physical conditions of our earliest environments. Yet, a rigorous, interdisciplinary understanding of that relationship has not been explored adequately and once better understood will inform our search for life beyond Earth. In this way, studies of the emergence of life must become a truly interdisciplinary effort, requiring a mix that expands the traditional platform of prebiotic chemistry to include geochemists, atmospheric chemists, geologists and geophysicists, astronomers, mission scientists and engineers, and astrobiologists.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87102976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep generative models for galaxy image simulations","authors":"F. Lanusse, R. Mandelbaum, Siamak Ravanbakhsh, Chun-Liang Li, P. Freeman, B. Póczos","doi":"10.1093/mnras/stab1214","DOIUrl":"https://doi.org/10.1093/mnras/stab1214","url":null,"abstract":"Image simulations are essential tools for preparing and validating the analysis of current and future wide-field optical surveys. However, the galaxy models used as the basis for these simulations are typically limited to simple parametric light profiles, or use a fairly limited amount of available space-based data. In this work, we propose a methodology based on Deep Generative Models to create complex models of galaxy morphologies that may meet the image simulation needs of upcoming surveys. We address the technical challenges associated with learning this morphology model from noisy and PSF-convolved images by building a hybrid Deep Learning/physical Bayesian hierarchical model for observed images, explicitly accounting for the Point Spread Function and noise properties. The generative model is further made conditional on physical galaxy parameters, to allow for sampling new light profiles from specific galaxy populations. We demonstrate our ability to train and sample from such a model on galaxy postage stamps from the HST/ACS COSMOS survey, and validate the quality of the model using a range of second- and higher-order morphology statistics. Using this set of statistics, we demonstrate significantly more realistic morphologies using these deep generative models compared to conventional parametric models. To help make these generative models practical tools for the community, we introduce GalSim-Hub, a community-driven repository of generative models, and a framework for incorporating generative models within the GalSim image simulation software.","PeriodicalId":8459,"journal":{"name":"arXiv: Instrumentation and Methods for Astrophysics","volume":"57 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89757098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}