J/A+A/699/A349ivo://CDS.VizieR/J/A+A/699/A349doi:10.26093/cds/vizier/bc-nv/ldejCDSPrudil Z.Debattista V.P.Beraldo e Silva L.Anderson S.R.,Gough-Kelly S.Kunder A.Rejkuba M.Gerhard O.Wyse R.F.G.,Koch-Hansen A.J.Rich R.M.Savino A.2026-08-03T06:55:52Z2025-07-22T09:52:39ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frvariable-starsradial-velocityvisible-astronomyIn this work, we derive systemic velocities for 8456 RR Lyrae stars. This is the largest dataset of these variables in the Galactic bulge to date. In combination with Gaia proper motions, we computed their orbits using an analytical gravitational potential similar to that of the Milky Way (MW) and identified interlopers from other MW structures, which amount to 22% of the total sample. Our analysis revealed that most interlopers are associated with the halo, and the remainder are linked to the Galactic disk. We confirm the previously reported lag in the rotation curve of bulge RR Lyrae stars, regardless of the removal of interlopers. The rotation patterns of metal-rich RR Lyrae stars are consistent with the pattern of nonvariable metal-rich giants, following the MW bar, while metal-poor stars rotate more slowly. The analysis of the orbital parameter space was used to distinguish bulge stars that in the bar reference frame have prograde orbits from those on retrograde orbits. We classified the prograde stars into orbital families and estimated the chaoticity (in the form of the frequency drift, log{Delta}{Omega}) of their orbits. RR Lyrae stars with banana-like orbits have a bimodal distance distribution, similar to the distance distribution seen in metal-rich red clump stars. The fraction of stars with banana-like orbits decreases linearly with metallicity, as does the fraction of stars on prograde orbits (in the bar reference frame). The retrograde-moving stars (in the bar reference frame) form a centrally concentrated nearly spherical distribution. From analyzing an N-body+SPH simulation, we found that some stellar particles in the central parts oscillate between retrograde and prograde orbits and that only a minority stays prograde over a long period of time. Based on the simulation, the ratio of prograde and retrograde stellar particles seems to stabilize within some gigayears after the bar formation. The nonchaoticity of retrograde orbits and their high numbers can explain some of the spatial and kinematical features of the MW bulge that have been often associated with a classical bulge.2025A&A...699A.349Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/699/A349CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AcA/69/321 : OGLE RR Lyrae stars in Galactic bulge & disk (Soszynski+, 2019)J/AcA/64/177 : VI light curves of Galactic Bulge RR Lyrae (Soszynski+, 2014)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/699/A349https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/699/A349http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/699/A349https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/699/A349https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/699/A349http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/699/A349GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/699/A349/table1 (Calculated systemic velocities of our RR Lyrae dataset)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/699/A349/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/699/A349/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/699/A349/table1?GETtext/xml+votable180.050000true267.5007864-35.61490110.0055555555555555564/1794 1803 5/7180 7182-7183 7192 7194-7195 7198-7199 7205 7209 7211 7216-7217 7220 7223 7226-7227 7230 7300 7312-7313 10591 6/28683 28686 28698-28699 28724 28726-28727 28772 28774-28775 28800-28801 28804-28805 28815-28817 28819 28828-28829 28835 28841 28872-28873 28876-28877 28884 28886-28889 28896 28898-28899 28902-28903 28914 29058 29064 29066 29191 29205 29207 29257 29260-29261 29264-29266 42359 42452-42453https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/699/A349?format=asciiOpticaldefaultJ/A+A/699/A349/table1Calculated systemic velocities of our RR Lyrae datasetrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDOGLE-ID (OGLE-BLG-RRLYR-NNNNN)meta.id;meta.maincharvsysSystemic velocitykm/sphys.velocdoublee_vsysError on systemic velocitykm/sstat.errordoubleSimbadSimbad column added by the CDSmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main