We present infrared JHK time series photometry of the variable star RR Lyr, that allows us to construct the first complete and accurate infrared light curves for this star. The derived mean magnitudes are <J>=6.74+/-0.02, <H>=6.60+/-0.03 and <K>=6.50+/-0.02. The <K> magnitude is used to estimate the reddening, the mass, the mean luminosity and the temperature of this variable star. The use of these RR Lyr data provides a more accurate absolute calibration of the P-L_K_-[Fe/H] relation, and a distance modulus (m-M)0=18.48+/-0.11 to the globular cluster Reticulum in the Large Magellanic Cloud.
We combine our previous optical spectroscopic and photometric analysis of 1600 stars located in the Orion Nebula Cluster (ONC) with our own and published near-infrared photometric surveys of the region in order to investigate the evidence for and properties of circumstellar disks. We use the near-infrared continuum excess as our primary disk diagnostic, although we also study sources with Ca II triplet emission and those designated as "proplyds."
The results of a photometric monitoring in the wavelength range 1-20um are presented for 37 oxygen-rich sources. The sample contains optically identified miras (13), M-type supergiants (3), type II OH/IR sources (20) and one unidentified object. Each source was observed on at least 13 occasions (up to 42) over a lapse of at least 1250 days (up to 2150) between 1984 and 1990 with the ESO 1-m telescope equipped with its standard infrared photometer.
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.
This paper supplements Kerschbaum and Hron (1994), where new JHKL'M observations of 200 Semiregular variables of types SRa and SRb were presented with additional 44 near infrared observations and 5 literature data sets. The total sample was defined in Kerschbaum & Hron (1992, Paper I) by means of a certain limit in bolometric magnitude. From the sample of 350 objects, 303 now have near infrared (NIR) photometry. In total 339 datasets are available because of some multiple observations. A detailed analysis of the whole dataset will be presented in a forthcoming paper.
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.
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.
We present JHKLM photometric data for FG Sge, the nucleus of the planetary nebula He 1-5, obtained from 1985 to 2001, carried out on the 125cm telescope of the Sternberg Astronomical Institude's Crimean Station.
