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<ri:Resource created="2016-02-15T07:55:31Z" 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>Time and positions of coronal bright points</title><shortName>J/A+A/587/A29</shortName><identifier>ivo://CDS.VizieR/J/A+A/587/A29</identifier><altIdentifier>doi:10.26093/cds/vizier.35870029</altIdentifier><curation><publisher ivo-id="ivo://CDS">CDS</publisher><creator><name>Sudar D.</name></creator><creator><name>Saar S.H.</name></creator><creator><name>Skokic I.</name></creator><creator><name>Poljancic Beljan I.</name></creator><creator><name>Brajsa R.</name></creator><date role="Updated">2016-02-15T06:56:27Z</date><date role="Created">2016-02-15T07:55:31Z</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>the-sun</subject><description>It is possible to detect and track coronal bright points (CBPs) in Solar Dynamics Observatory / Atmospheric Imaging Assembly (SDO/AIA) images. A combination of high resolution and high cadence provides a wealth of data that can be used to determine velocity flows on the solar surface with very high accuracy. We derived a very accurate solar rotation profile and investigated meridional flows, torsional oscillations, and horizontal Reynolds stress based on ~6 months of SDO/AIA data. We used a segmentation algorithm to detect CBPs in SDO/AIA images. We also used invariance of the solar rotation profile with central meridian distance (CMD) to determine the height of CBPs in the 19.3nm channel. The best fit solar rotation profile is given by {omega}(b)=(14.4060+/-0.0051+(-1.662+/-0.050)sin^2^b+ (-2.742+/-0.081)sin^4^b){deg}/day. The height of CBPs in the SDO/AIA 19.3nm channel was found to be ~6500km. Meridional motion is predominantly poleward for all latitudes, while solar velocity residuals show signs of torsional oscillations. Horizontal Reynolds stress was found to be smaller than in similar works, but still showed transfer of angular momentum towards the solar equator. Most of the results are consistent with Doppler measurements rather than tracer measurements. The fairly small calculated value of horizontal Reynolds stress might be due to the particular phase of the solar cycle. Accuracy of the calculated rotation profile indicates that it is possible to measure changes in the profile as the solar cycle evolves. Analysis of further SDO/AIA CBP data will also provide a better understanding of the temporal behaviour of the rotation velocity residuals, meridional motions, and Reynolds stress.</description><source format="bibcode">2016A&amp;A...587A..29S</source><referenceURL>https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/587/A29</referenceURL><type>Catalog</type><contentLevel>Research</contentLevel><relationship><relationshipType>IsServedBy</relationshipType><relatedResource ivo-id="ivo://CDS.VizieR/TAP">TAP VizieR generic service</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/587/A29</accessURL><mirrorURL title="VizieR at IUCAA: Pune, India">https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/587/A29</mirrorURL><mirrorURL title="VizieR at SAAO: SAAO, South Africa">http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/587/A29</mirrorURL></interface></capability><capability><interface xsi:type="vs:ParamHTTP"><accessURL use="base">https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/587/A29</accessURL><mirrorURL title="VizieR at IUCAA: Pune, India">https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/587/A29</mirrorURL><mirrorURL title="VizieR at SAAO: SAAO, South Africa">http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/587/A29</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"/></coverage><tableset><schema><name>default</name><table><name>J/A+A/587/A29/table1</name><description>Time in JD and position of CBPs in pixels</description><column><name>recno</name><description>Record number assigned by the VizieR team. Should Not be used for identification.</description><ucd>meta.record</ucd><dataType xsi:type="vs:VOTableType">int</dataType></column><column><name>JD</name><description>Julian Date of observation (JD-2450000.0)</description><unit>d</unit><ucd>time.epoch</ucd><dataType xsi:type="vs:VOTableType">double</dataType></column><column><name>ID</name><description>ID number of CBP</description><ucd>meta.id;meta.main</ucd><dataType xsi:type="vs:VOTableType">long</dataType></column><column><name>xPos</name><description>x position of CBP in pixels</description><unit>pix</unit><ucd>pos.cartesian.x</ucd><dataType xsi:type="vs:VOTableType">double</dataType></column><column><name>yPos</name><description>y position of CBP in pixels</description><unit>pix</unit><ucd>pos.cartesian.y</ucd><dataType xsi:type="vs:VOTableType">double</dataType></column></table></schema></tableset></ri:Resource>