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- ID:
- ivo://CDS.VizieR/J/PASP/124/140
- Title:
- UBVRI Hp BT and VT photonic responses
- Short Name:
- J/PASP/124/140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have calculated improved photonic passbands for the UBVRI, Hipparcos Hp, and Tycho BT and VT standard systems using the extensive spectrophotometric libraries of NGSL and MILES. Using the Hp passband, we adjusted the absolute flux levels of stars in the spectrophotometric libraries so that their synthetic Hp magnitudes matched the precise Hipparcos Catalogue value. Synthetic photometry based on the renormalized fluxes was compared with the standard UBVRI, BT and VT magnitudes, and revised synthetic zero points were determined. The Hipparcos and Tycho photometry system zero points were also compared with the V-magnitude zero points of the SAAO UBVRI system, the homogenized UBV system, and the Walraven VB system.
- ID:
- ivo://CDS.VizieR/J/A+A/605/A99
- Title:
- UBVRI images of Barnard 207
- Short Name:
- J/A+A/605/A99
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Barnard 207 (B207, LDN 1489, LBN 777), also known as the Vulture Head nebula, is a cometary globule in the Taurus-Auriga-Perseus Molecular Cloud region. B207 is known to host a Class I protostar, IRAS 04016+2610, located at a projected distance of ~8400au from the dense core centre. Using imaging and photometry over a wide wavelength range, from UV to sub-mm, we study the physical properties of B207 and the dust grains contained within. The core density, temperature, and mass are typical of other globules found in the Milky Way interstellar medium (ISM). The increase in the dust albedo with increasing optical wavelengths, along with the detection of coreshine in the near infrared, indicates the presence of larger dust grains in B207. The measured optical, near-, mid- and far-infrared intensities are in agreement with the CMM+AMM and CMM+AMMI dust grain type of the THEMIS model, suggesting mantle formation on the dust grains throughout the globule. We investigate the possibility of turbulence being responsible for diffusing dust grains from the central core to external outer layers of B207. However, in situ formation of large dust grains cannot be excluded.
- ID:
- ivo://CDS.VizieR/J/ApJS/193/1
- Title:
- UBVRIJHK color-temperature calibration
- Short Name:
- J/ApJS/193/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A collection of Johnson/Cousins photometry for stars with known [Fe/H] is used to generate color-color relations that include the abundance dependence. Literature temperature and bolometric correction (BC) dependences are attached to the color relations. The JHK colors are transformed to the Bessell & Brett (1988PASP..100.1134B) homogenized system. The main result of this work is the tabulation of seven colors and the V-band BC as a function of Teff, logg, and [Fe/H] for -1.06<V-K<10.2 and an accompanying interpolation program. Improvements to the present calibration would involve filling photometry gaps, obtaining more accurate and on-system photometry, knowing better logg and [Fe/H] values, improving the statistics for data-impoverished groups of stars such as metal-poor K dwarfs, applying small tweaks in the processing pipeline, and obtaining better empirical temperature and BC relations, especially for supergiants and M stars. A way to estimate dust extinction from M dwarf colors is pointed out.
- ID:
- ivo://CDS.VizieR/J/A+A/508/371
- Title:
- UBVRIJHK observations of SN 2007gr
- Short Name:
- J/A+A/508/371
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometric and spectroscopic observations at optical and near-infrared wavelengths of the nearby type-Ic supernova 2007gr. These represent the most extensive data-set to date of any supernova of this sub-type, with frequent coverage from shortly after discovery to more than one year post-explosion.
- ID:
- ivo://CDS.VizieR/J/MNRAS/411/2530
- Title:
- UBVRIJHK photometry in NGC1624
- Short Name:
- J/MNRAS/411/2530
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive multiwavelength analysis of the young cluster NGC 1624 associated with the HII region Sh2-212 using optical UBVRI photometry, optical spectroscopy and GMRT radio continuum mapping along with the near-infrared (NIR) JHK archival data.
- ID:
- ivo://CDS.VizieR/J/AJ/122/2055
- Title:
- UBVRIJHK photometry of AGN field stars
- Short Name:
- J/AJ/122/2055
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a total of 12,436 photometric measures of 371 field stars of 26 quasars in the visible (UBVRI) and 22,276 photometric measures of 122 field stars of 13 quasars in the near-infrared (JHK), giving a total of 34,712 measures. Of these, 115 stars in 12 fields are calibrated in both ranges. One further field, Mrk 421, was calibrated, but on close examination all sources were found to be probably nonstellar; thus these results are not included here. The stars observed cover the range from V=11 to V=20 and from K=9 to K=17 and are well distributed around the sky north of declination -30{deg}. This represents the initial sample of an extensive catalog of calibrated fields that will cover the northern sky down to declination -30{deg} and that will cover a wide range of Galactic latitudes. These fields will be useful both for photometry of AGNs in the range from B to K and also as faint calibration standards for large telescopes. The median absolute total error on the photometry, including all known error sources, ranges from 0.008mag in J to 0.034mag in B. These errors will be greatly reduced with the addition of further data in the future, although the final precision is fundamentally limited by the photometric errors in the existing lists of calibration stars used to calibrate these data.
- ID:
- ivo://CDS.VizieR/J/A+A/509/A104
- Title:
- UBVRIJHK photometry of Dolidze 25
- Short Name:
- J/A+A/509/A104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The analysis of our deep UBVRIJHK photometry of Dolidze 25, located in the central area of the HII region Sh 2-284, reveals a young cluster with coeval MS and PMS populations of age 3.2-5Myr. The mass function for the optical PMS population in the mass range above 1.3-3.5M_{sun}_ is well fitted by a Salpeter mass function. On the other hand, the NIR photometry results indicate a large number of sources with H-Ks excess, practically distinct from the optical PMS candidate members. In addition, a distinctly older cluster member population of age 40Myr is suggested. The distance determined for the cluster from quantitative fits to ZAMS and isochrones (3.6kpc) is distinctly lower than previously published values. This result originates in the consistent use of low metallicity models for ZAMS fitting, applying published metallicity values for the cluster
- ID:
- ivo://CDS.VizieR/J/A+A/441/451
- Title:
- UBVRIJHK photometry of E-type galaxies
- Short Name:
- J/A+A/441/451
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Colour gradients are considered for a sample of circa 50 E-type galaxies in the Local Supercluster. The new data includes isophotal colour profiles in J-H, J-K, V-J and V-K, measured using 2MASS frames mostly from the Large Galaxies Atla s, V frames from previous work and V profiles from the literature. This is supplemented by U-B, B-V, B-R, V-I colour gradients obtained anew from published photometric data. The here available file gives our zero-point colours at r_e_/2 and the measured gradients for 54 objects, but for missing data.
- ID:
- ivo://CDS.VizieR/J/PASP/126/521
- Title:
- UBVRIJHK photometry of RR Lyrae in M4
- Short Name:
- J/PASP/126/521
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical and near-infrared UBVRIJHK photometry of stars in the Galactic globular cluster M4 (NGC 6121) based upon a large corpus of observations obtained mainly from public astronomical archives. We concentrate on the RR Lyrae variable stars in the cluster, and make a particular effort to accurately reidentify the previously discovered variables. We have also discovered two new probable RR Lyrae variables in the M4 field: one of them by its position on the sky and its photometric properties is a probable member of the cluster, and the second is a probable background (bulge?) object. We provide accurate equatorial coordinates for all 47 stars identified as RR Lyraes, new photometric measurements for 46 of them, and new period estimates for 45. We have also derived accurate positions and mean photometry for 34 more stars previously identified as variable stars of other types, and for an additional five non-RR Lyrae variable stars identified for the first time here. We present optical and near-infrared color-magnitude diagrams for the cluster and show the locations of the variable stars in them. We present the Bailey (period-amplitude) diagrams and the period-frequency histogram for the RR Lyrae stars in M4 and compare them to the corresponding diagrams for M5 (NGC 5904). We conclude that the RR Lyrae populations in the two clusters are quite similar in all the relevant properties that we have considered. The mean periods, pulsation-mode ratios, and Bailey diagrams of these two clusters show support for the recently proposed "Oosterhoff-neutral" classification.
