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- ID:
- ivo://CDS.VizieR/J/PAZh/32/866
- Title:
- JHKLM photometry for 22 hot stars
- Short Name:
- J/PAZh/32/866
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the JHKLM photometry for 22 hot stars, 11 of which were identified in the GCVS. For all of the observed objects, we have estimated the interstellar reddening, angular diameters, and the volume emission measures of their gaseous shalls.
- ID:
- ivo://CDS.VizieR/J/A+AS/101/513
- Title:
- JHKLM photometry of C stars
- Short Name:
- J/A+AS/101/513
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present J H K L M photometry for 25 Carbon stars, and 450, 600, 800 and 1100 {mu}m for 12 carbon stars and the S-star W Aql. Carbon stars reside on a different part of the [12-25], [K-L] diagram than O-rich stars. Our work confirms earlier observations and shows this relation to hold up at least [K-L] ~ 8mag.
- ID:
- ivo://CDS.VizieR/J/PAZh/33/657
- Title:
- JHKLM photometry of eight planetary nebulae
- Short Name:
- J/PAZh/33/657
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We discuss the infrared (IR) (1.25-5microns) photometry of eight planetary nebulae performed in 1999-2006. For all of the nebulae under study, we have firmly established IR brightness and color variations on time scales shorter than one year and up to 6-8 years. The greatest IR brightness variations were observed in IC 2149, IC 4997, and NGC 7662. Their J magnitudes varied within 0.2-0.25mag. In the remaining objects, the J magnitude variations did not exceed 0.15mag. All of the planetary nebulae under study exhibited IR color variations. Based on the IR photometry, we have classified the central regions of planetary nebula NGC 1514 and of the northern part of NGC 7635 seen through a 12" aperture as B(3-7) main-sequence star (NGC 1514) and O9.5 upper-main-sequence star (NGC 7635). The nebulae IC 4997 and NGC 7027 exhibited an excess emission (with respect to the emission from a hot source) at wavelength more than 2.5micron.
- ID:
- ivo://CDS.VizieR/J/A+A/227/82
- Title:
- JHKLM photometry of 'IRAS-discovered' stars
- Short Name:
- J/A+A/227/82
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents results of JHKLM photometry data analysis of 249 southern 'IRAS-discovered' stars, which exhibit an emission feature at 11.3 microns in their low-resolution spectra (class 4n stars). The method of Epchtein et al. (1987A&AS...71...39E) is used to separate oxygen-rich and carbon-rich stars on the basis of their sole NIR and IRAS broad-band fluxes. It is shown that NIR data are necessary to calculate the total IR energy received from IRAS stars and such fundamental parameters as individual mass loss rates. An evolutionary model is developed to match the sequence of stars in color diagrams. It is suggested that the sequence of increasing optical depths might not be an evolutionary sequence, but would rather reflect the termination of a process in which the near-IR index increases very quickly at the beginning and is strongly dependent on the mass loss rate.
- ID:
- ivo://CDS.VizieR/J/AJ/125/3311
- Title:
- JHKL'M photometry of northern bright stars
- Short Name:
- J/AJ/125/3311
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of 8yr of infrared photometric monitoring of a large sample of stars visible from Teide Observatory (Tenerife, Canary Islands). The final archive is made up of 10949 photometric measures through a standard InSb single-channel photometer system, principally in JHK, although some stars have measures in L'. The core of this list of stars is the standard-star list developed for the Carlos Sanchez Telescope. A total of 298 stars have been observed on at least two occasions on a system carefully linked to the zero point defined by Vega. We present high-precision photometry for these stars. The median uncertainty in magnitude for stars with a minimum of four observations and thus reliable statistics ranges from 0.0038mag in J to 0.0033mag in K. Many of these stars are faint enough to be observable with array detectors (42 are K>8) and thus to permit a linkage of the bright and faint infrared photometric systems. We also present photometry of an additional 25 stars for which the original measures are no longer available, plus photometry in L' and/or M of 36 stars from the main list.
- ID:
- ivo://CDS.VizieR/J/A+A/375/527
- Title:
- JHKL' photometry of AGB stars
- Short Name:
- J/A+A/375/527
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Multi-epoch near-infrared photometry for a sample of long period variables (SR, L, Mira). Data have been obtained at the Observatorio del Teide using the 1.5m "Carlos Sanchez Telescope" with the "CVF Photometer-Spectrophotometer". The sample has been selected based on three observing programs at the ISO satellite.
- ID:
- ivo://CDS.VizieR/J/AJ/104/28
- Title:
- JHKL photometry of BL Lac Objects
- Short Name:
- J/AJ/104/28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Homogeneous J, H, K, L, photometry of 42 BL Lacertae objects is presented. The observations cover a period of 3 yr with a typical time interval of 6 months.
- ID:
- ivo://CDS.VizieR/J/A+A/438/663
- Title:
- JHKL photometry of 30 Dor
- Short Name:
- J/A+A/438/663
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- L-band data of 30 Doradus at 3.5 micron taken with SPIREX (South Pole Infrared Explorer) is presented. The photometry was combined with 2MASS (<II/246>) JHK data at 1.25 -2.2 micron. Colour-colour and colour-magnitude diagrams are constructed and used to determine the sources with infrared excess. These are interpreted as circumstellar disks, and enable the fraction of sources with disks (the cluster disk fraction or CDF) to be determined. We find that ~42% of the sources detected at L-band in 30 Doradus have an IR-excess.
- ID:
- ivo://CDS.VizieR/J/ApJ/453/616
- Title:
- JHKL photometry of 12 micron galaxy sample
- Short Name:
- J/ApJ/453/616
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Aperture photometry from our own observations and the literature is presented for the 12 um galaxies in the near-infrared J, H, and K bands and, in some cases, in the L band. These data are corrected to "total" near-infrared magnitudes (with a typical uncertainty of 0.3mag) for a direct comparison with our IRAS fluxes which apply to the entire galaxy. The corrected data are used to derive integrated total near-infrared and far-infrared luminosities. We then combine these with blue photometry and an estimate of the flux contribution from cold dust at wavelengths longward of 100um to derive the first bolometric luminosities for a large sample of galaxies. The presence of nonstellar radiation at 2-3um correlates very well with nonstellar IRAS colors. This enables us to identify a universal Seyfert nuclear continuum from near- to far-infrared wavelengths. Thus, there is a sequence of infrared colors which runs from a pure "normal galaxy" to a pure Seyfert/quasar nucleus. Seyfert 2 galaxies fall close to this same sequence, although only a few extreme narrow-line Seyfert galaxies have quasar-like colors, and these show strong evidence of harboring an obscured broad-line region. A corollary is that the host galaxies of Seyfert nuclei have normal near- to far-infrared spectra on average. Starburst galaxies lie significantly off the sequence, having a relative excess of 60um emission probably as a result of stochastically heated dust grains. We use these correlations to identify several combinations of infrared colors which discriminate between Seyfert 1 and 2 galaxies, LINERs, and ultraluminous starbursts. In the infrared, Seyfert 2 galaxies are much more like Seyfert 1s than they are like starbursts, presumably because both kinds of Seyferts are heated by a single central source, rather than a distributed region of star formation. Moreover, combining the [25-2.2um] color with the [60-12um] color, it appears that Seyfert 1 galaxies are segregated from Seyfert 2 galaxies and starburst galaxies in a well-defined region characterized by the hottest colors, corresponding to the flattest spectral slopes. Virtually no Seyfert 2 galaxy is present in such a region. To reconcile this with the "unified scheme" for Seyfert 1 and 2 galaxies would therefore require that the higher frequency radiation from the nuclei of Seyfert 2 galaxies to be absorbed by intervening dust and re-emitted at lower frequencies. We find that bolometric luminosity is most closely proportional to 12um luminosity. The 60 and 25um luminosities rise faster than linearly with bolometric luminosity, while the optical flux rises less than linearly with bolometric luminosity. This result is a confirmation of the observation that more luminous disk galaxies have relatively more dust-enshrouded stars. Increases in the dust content shifts luminosity from the optical to 25-60um, while leaving a "pivot point" in the mid-IR essentially unchanged. Thus, 12um selection is the closest available approximation to selection by a limiting bolometric flux, which is approximately 14 times nu.L_nu at 12um for non-Seyfert galaxies. It follows that future deep surveys in the mid-infrared, at wavelengths of 8-12um, will simultaneously provide complete samples to different bolometric flux levels of normal and active galaxies, which will not suffer the strong selection effects present both in the optical-UV and far-infrared.
