J/AJ/126/1286ivo://CDS.VizieR/J/AJ/126/1286doi:10.26093/cds/vizier.51261286CDSLin W.Zhou X.Burstein D.Windhorst R.A.Chen J.Chen W.-P.Jiang Z.,Kong X.Ma J.Sun W.-H.Wu H.Xue S.Zhu J.2023-04-06T16:50:56Z2005-12-20T21:55:52ZCDS support team

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

cds-question@unistra.frh-ii-regionsspectroscopyIn a first of a series of studies of the H{alpha}+[NII] emission from nearby spiral galaxies, we present measurements of H{alpha}+[NII] emission from HII regions in M81. Our method uses large-field CCD images and long-slit spectra and is part of the ongoing Beijing-Arizona-Taipei-Connecticut Sky Survey (the BATC survey). The CCD images are taken with the National Astronomical Observatories of China (NAOC) 0.6/0.9m f/3 Schmidt telescope at the Xinglong Observing Station, using a multicolor filter set. The observations reported here were taken on 30 individual nights over the time period 1995 February 5 to 1997 February 19. Spectra of 10 of the brightest HII regions are obtained using the NAOC 2.16m telescope with a Tek 1024x1024 CCD, between 1997 April 9 and 11. The continua of the spectra are calibrated by flux-calibrated images taken from the Schmidt observations. We determine the continuum component of our H{alpha}+[NII] image via interpolation from the more accurately measured backgrounds (M81 starlight) obtained from the two neighboring (in wavelength) BATC filter images. We use the calibrated fluxes of H{alpha}+[NII] emission from the spectra to normalize this interpolated, continuum-subtracted H{alpha}+[NII] image. We estimate the zero-point uncertainty of the measured H{alpha}+[NII] emission flux to be 8%. A catalog of H{alpha}+[NII] fluxes for 456 HII regions is provided, with those fluxes being on a more consistent linear scale than previously available. The logarithmically binned H{alpha}+[NII] luminosity function of HII regions is found to have slope {alpha}=-0.70, consistent with previous results (which allowed {alpha}=-0.5 to -0.8). From the overall H{alpha}+[NII] luminosity of the HII regions, the star formation rate of M81 is found to be ~0.68M_{sun}_/yr, modulo uncertainty with extinction corrections.2003AJ....126.1286Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/126/1286CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/438/181 : Observations of H II Regions in M81 (Hill+ 1995)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/126/1286https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/126/1286http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/126/1286https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/126/1286https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/126/1286http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/126/1286GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/126/1286/table4 (Catalog of Optically Bright H II Regions with H{alpha} Flux)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/126/1286/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/126/1286/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/126/1286/table4?GETtext/xml+votable180.050000true148.582583369.13141670.0055555555555555566/7606https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/126/1286?format=asciiOpticaldefaultJ/AJ/126/1286/table4Catalog of Optically Bright H II Regions with H{alpha} FluxrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNumH II region PSK index number (1)charRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainXoffX offset distance from the galaxy center (2)arcsecfloatYoffY offset distance from the galaxy center (2)arcsecfloatFluxH{alpha}+[NII] flux1e-19W.m**-2inte_FluxThe 1 {sigma} error in Flux1e-19W.m**-2intDiamAperture diameter used to measure FluxarcsecfloatPFlux? Flux measured by Petit et al. (1988A&AS...74..475P)1e-16mW.m**-2intnullableS/NSignal-to-noise ratiofloat