J/AJ/149/127ivo://CDS.VizieR/J/AJ/149/127doi:10.26093/cds/vizier.51490127CDSLim B.Sung H.Bessell M.S.Kim J.S.Hur H.Park B.-G.2015-06-24T21:12:45Z2015-05-19T13:57:45ZCDS support team

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

cds-question@unistra.fropen-star-clustersinfrared-photometryvisible-astronomybroad-band-photometryh-alpha-photometryYoung open clusters located in the outer Galaxy provide us with an opportunity to study star formation activity in a different environment from the solar neighborhood. We present a UBVI and H{alpha} photometric study of the young open clusters NGC 1624 and NGC 1931 that are situated toward the Galactic anticenter. Various photometric diagrams are used to select the members of the clusters and to determine the fundamental parameters. NGC 1624 and NGC 1931 are, on average, reddened by <E(B-V)>=0.92+/-0.05 and 0.74+/-0.17mag, respectively. The properties of the reddening toward NGC 1931 indicate an abnormal reddening law (R_V,cl_=5.2+/-0.3). Using the zero-age main sequence fitting method we confirm that NGC 1624 is 6.0+/-0.6kpc away from the Sun, whereas NGC 1931 is at a distance of 2.3+/-0.2kpc. The results from isochrone fitting in the Hertzsprung-Russell diagram indicate the ages of NGC 1624 and NGC 1931 to be less than 4 and 1.5-2.0Myr, respectively. We derived the initial mass function (IMF) of the clusters. The slope of the IMF ({Gamma}_NGC1624_=-2.0+/-0.2 and {Gamma}_NGC1931_=-2.0+/-0.1) appears to be steeper than that of the Salpeter/Kroupa IMF. We discuss the implication of the derived IMF based on simple Monte-Carlo simulations and conclude that the property of star formation in the clusters does not seem to be significantly different from that in the solar neighborhood.2015AJ....149..127Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/149/127CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/ocl : Optically visible open clusters and Candidates (Dias+ 2002-2014)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)J/MNRAS/438/1451 : UBVIHa photometry of IC 1848 (Lim+, 2014; Paper II)J/ApJ/764/172 : UBVRI photometry of stars toward NGC 1931 (Pandey+, 2013)J/AJ/145/46 : UBVIc photometry in Westerlund 1 (Lim+, 2013)J/AJ/145/37 : UBVI and Ha CCD photometry of NGC 6231 (Sung+, 2013)J/AJ/143/41 : UBVIc photometry of star clusters Tr14 and Tr16 (Hur+, 2012)J/MNRAS/411/2530 : UBVRIJHK photometry in NGC1624 (Jose+, 2011)J/AJ/138/1116 : A Spitzer view of NGC 2264 (Sung+, 2009)J/AJ/135/441 : VRIHa photometry in NGC 2264 (Sung+, 2008)J/AJ/128/1684 : NGC 2264: VRIHa photometry (Sung+, 2004)J/AJ/127/1014 : CCD UBVRIHa photometry in NGC 3603 (Sung+, 2004)J/AJ/120/333 : UBVRI and Ha in NGC 6530 (Sung+, 2000)J/MNRAS/310/982 : UBVI CCD Photometry of M11 - II. (Sung+ 1999)J/AJ/115/734 : NGC 6231 UBVRI and Ha photometry (Sung+ 1998)J/AJ/114/2644 : UBVRIHa photometry of NGC2264 (Sung+, 1997)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/149/127https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/149/127http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/149/127https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/149/127https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/149/127http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/149/127GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/149/127/table4 (Photometric data for NGC 1624 (2015-06-02 version))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/149/127/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/149/127/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/149/127/table4?GETtext/xml+votable180.050000true69.847666750.33811110.005555555555555556Cone search capability for table J/AJ/149/127/table5 (Photometric data for NGC 1931 (2015-06-02 version))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/149/127/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/149/127/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/149/127/table5?GETtext/xml+votable180.050000true82.746708334.19250.0055555555555555566/1297 1300 1848 245072.263356695087955e-19 3.921900021377621e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/149/127?format=asciiOpticalInfrareddefaultJ/AJ/149/127/table4Photometric data for NGC 1624 (2015-06-02 version)Star[1/3727] Number of the star (in cluster)meta.numberintprimaryRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainVmag[10.8/22.5]? V-band magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? The uncertainty in Vmagmagstat.error;phot.mag;em.opt.Vfloatnullableo_Vmag[0/4] Number of observations for Vmagmeta.numberintImag[9.4/20.3]? I-band magnitudemagphot.mag;em.opt.Ifloatnullablee_Imag? The uncertainty in Imagmagstat.error;phot.mag;em.opt.Ifloatnullableo_Imag[0/5] Number of observations for Imagmeta.numberintV-I? The (V-I) color indexmagphot.color;em.opt.V;em.opt.Ifloatnullablee_V-I? The uncertainty in V-Imagstat.error;phot.color;em.opt.Vfloatnullableo_V-I[0/4] Number of observations for V-Imeta.numberintB-V? The (B-V) color indexmagphot.color;em.opt.B;em.opt.Vfloatnullablee_B-V? The uncertainty in B-Vmagstat.error;phot.color;em.opt.Bfloatnullableo_B-V[0/4] Number of observations for B-Vmeta.numberintU-B? The (U-B) color indexmagphot.color;em.opt.U;em.opt.Bfloatnullablee_U-B? The uncertainty in U-Bmagstat.error;phot.color;em.opt.Ufloatnullableo_U-B[0/4] Number of observations for U-Bmeta.numberintHa-C? The H{alpha} color index (C=(V+I)/2)magphot.color;em.opt.V;em.line.Halphafloatnullablee_Ha-C? The uncertainty in Ha-Cmagstat.errorfloatnullableo_Ha-C[0/2] Number of observations for Ha-Cmeta.numberint2MASSThe 2MASS identifier (HHMMSSss+DDMMSSs, J2000)meta.idcharHa[Hh] H{alpha} emission status (1)meta.code.statuscharJ/AJ/149/127/table5Photometric data for NGC 1931 (2015-06-02 version)Star[1/3727] Number of the star (in cluster)meta.numberintprimaryRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainVmag[10.8/22.5]? V-band magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? The uncertainty in Vmagmagstat.error;phot.mag;em.opt.Vfloatnullableo_Vmag[0/4] Number of observations for Vmagmeta.numberintImag[9.4/20.3]? I-band magnitudemagphot.mag;em.opt.Ifloatnullablee_Imag? The uncertainty in Imagmagstat.error;phot.mag;em.opt.Ifloatnullableo_Imag[0/5] Number of observations for Imagmeta.numberintV-I? The (V-I) color indexmagphot.color;em.opt.V;em.opt.Ifloatnullablee_V-I? The uncertainty in V-Imagstat.error;phot.color;em.opt.Vfloatnullableo_V-I[0/4] Number of observations for V-Imeta.numberintB-V? The (B-V) color indexmagphot.color;em.opt.B;em.opt.Vfloatnullablee_B-V? The uncertainty in B-Vmagstat.error;phot.color;em.opt.Bfloatnullableo_B-V[0/4] Number of observations for B-Vmeta.numberintU-B? The (U-B) color indexmagphot.color;em.opt.U;em.opt.Bfloatnullablee_U-B? The uncertainty in U-Bmagstat.error;phot.color;em.opt.Ufloatnullableo_U-B[0/4] Number of observations for U-Bmeta.numberintHa-C? The H{alpha} color index (C=(V+I)/2)magphot.color;em.opt.V;em.line.Halphafloatnullablee_Ha-C? The uncertainty in Ha-Cmagstat.errorfloatnullableo_Ha-C[0/2] Number of observations for Ha-Cmeta.numberint2MASSThe 2MASS identifier (HHMMSSss+DDMMSSs, J2000)meta.idcharHa[Hh] H{alpha} emission status (1)meta.code.statuschar