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<ri:Resource created="2023-08-28T09:08:08Z" status="active" updated="2025-05-19T09:50:00Z" version="1.2" xmlns:ri="http://www.ivoa.net/xml/RegistryInterface/v1.0" xmlns:vr="http://www.ivoa.net/xml/VOResource/v1.0" xmlns:vs="http://www.ivoa.net/xml/VODataService/v1.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.ivoa.net/xml/VOResource/v1.0 http://vo.ari.uni-heidelberg.de/docs/schemata/VOResource.xsd http://www.ivoa.net/xml/VODataService/v1.1 http://vo.ari.uni-heidelberg.de/docs/schemata/VODataService.xsd" xsi:type="vs:CatalogService"><title>Light curves neural network approximation</title><shortName>J/A+A/677/A16</shortName><identifier>ivo://CDS.VizieR/J/A+A/677/A16</identifier><altIdentifier>doi:10.26093/cds/vizier.36770016</altIdentifier><curation><publisher ivo-id="ivo://CDS">CDS</publisher><creator><name>Demianenko M.</name></creator><creator><name>Malanchev K.</name></creator><creator><name>Samorodova E.</name></creator><creator><name>Sysak M.</name></creator><creator><name>Shiriaev A.,Derkach D.</name></creator><creator><name>Hushchyn M.</name></creator><date role="Updated">2024-11-28T20:05:04Z</date><date role="Created">2023-08-28T09:08:08Z</date><contact><name>CDS support team</name><address>CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France</address><email>cds-question@unistra.fr</email></contact></curation><content><subject>supernovae</subject><subject>astronomical-models</subject><subject>photometry</subject><subject>visible-astronomy</subject><description>Modern time-domain photometric surveys collect a lot of observations of various astronomical objects, and the coming era of large-scale surveys will provide even more information. Most of the objects have never received a spectroscopic follow-up, which is especially crucial for transients, e.g., supernovae. Flux time series are actively used as an affordable alternative for photometric classification and characterization, e.g., peak identification and luminosity decline estimation. However, the collected time series are multidimensional, irregularly sampled, may contain outliers, and do not have well-defined systematic uncertainties. This paper presents a search for the best-performing methods to approximate over time and wavelength the observed light curves for generating time series with regular time steps in each passband. We examine several light curve approximation methods based on neural networks such as Multilayer Perceptrons, Bayesian Neural Networks, and Normalizing Flows to approximate observations of a single light curve. Tests based on both the simulated PLAsTiCC and real Zwicky Transient Facility Bright Transient Survey data samples demonstrate that even a few observations are enough to fit networks and improve the quality of approximation compared to state-of-the-art models. The methods described in this work have lower computational complexity and work significantly faster than Gaussian Processes. Additionally, we analyze the performance of the approximation techniques in perspective of further peak identification and transients classification. The study results are released in an open and user-friendly Fulu Python library available on GitHub for the scientific community.</description><source format="bibcode">2023A&amp;A...677A..16D</source><referenceURL>https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/677/A16</referenceURL><type>Catalog</type><contentLevel>Research</contentLevel><relationship><relationshipType>IsServedBy</relationshipType><relatedResource ivo-id="ivo://CDS.VizieR/TAP">TAP VizieR generic service</relatedResource></relationship><relationship><relationshipType>related-to</relationshipType><relatedResource>https://github.com/HSE-LAMBDA/fulu : HSE-LAMBDA/fulu programs</relatedResource></relationship></content><rights>https://cds.unistra.fr/vizier-org/licences_vizier.html</rights><capability><interface xsi:type="vr:WebBrowser"><accessURL use="full">https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/677/A16</accessURL><mirrorURL title="VizieR at IUCAA: Pune, India">https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/677/A16</mirrorURL><mirrorURL title="VizieR at SAAO: SAAO, South Africa">http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/677/A16</mirrorURL></interface></capability><capability><interface xsi:type="vs:ParamHTTP"><accessURL use="base">https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/677/A16</accessURL><mirrorURL title="VizieR at IUCAA: Pune, India">https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/677/A16</mirrorURL><mirrorURL title="VizieR at SAAO: SAAO, South Africa">http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/677/A16</mirrorURL><queryType>GET</queryType><resultType>text/xml+votable</resultType></interface></capability><capability standardID="ivo://ivoa.net/std/TAP#aux"><interface xsi:type="vs:ParamHTTP" role="std"><accessURL use="base">https://tapvizier.cds.unistra.fr/TAPVizieR/tap</accessURL></interface></capability><coverage><footprint ivo-id="ivo://ivoa.net/std/moc"/><waveband>Optical</waveband></coverage><tableset><schema><name>default</name><table><name>J/A+A/677/A16/table9</name><description>Estimated peaks for the Zwicky Transient Facility (ZTF) Bright Transient Survey (BTS) objects</description><column><name>recno</name><description>Record number assigned by the VizieR team. 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