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This paper presents mass, temperature profile, and the variation of Planck’s function in different regions around asymptotic giant branch (AGB) stars. The physics of the interstellar medium (ISM) is extremely complex because the medium is very inhomogeneous and is made of regions with fairly diverse physical conditions. We studied the dust environment such as flux, temperature, mass, and inclination angle of the cavity structure around C-rich asymptotic giant branch stars in 60 μm and 100 μm wavelengths band using Infrared Astronomical Survey. We observed the data of AGB stars named IRAS 01142+6306 and IRAS 04369+4501. Flexible image transport system image was downloaded from Sky View Observatory; we obtained the surrounding flux density using software Aladin v2.5. The average dust color temperature and mass are found to be 25.08 K, 23.20 K and 4.73 × ;1026 kg (0.00024 M⊙), 2.58 × 1028 kg (0.013 M⊙), respectively. The dust color temperature ranges from 18.76 K ± 3.16 K to 33.21K ± K and 22.84 K ± 0.18 K to 24.48 K ± 0.63 K. The isolated cavity like structure around the AGB stars has an extension of 45.67 pc × 17.02 pc and 42.25 pc × 17.76 pc, respectively. The core region is found to be edge-on having an inclination angle of 79.46° and 73.99°, respectively.

We present the distribution of dust color temperature, Planck's function, dust mass, and visual extinction in the far-infrared (140 μm and 90 μm) AKARI surveys of the Crab Nebula using Sky View Virtual Observatory. With a systematic search of a supernova remnants, we found Crab Nebula at R. A. (J2000) / Decl. (J2000) = 05h 34' 31.94"/+22° 00' 52.20". The maximum flux is found to be 145.94 MJysr-1 at 140 μm and 177.01 MJysr-1 at 90 μm wavelength. The total dust mass of the Supernova remnant is estimated to be 6.11×1039 kg (3.07×109 Mʘ) and the dust color temperature is found in the range between 31.16 K to 47.11 K with mean value of temperature of 38.07 K. Similarly we obtained the value of Planck’s function in the range of 3.96 × 10-15 Wm-2sr-1Hz-1 to 1.96 × 10-14 Wm-2sr-1Hz-1 with average value 9.59 × 10-15 Wm-2sr-1Hz-1. The value of visual extinction ranges from 9.21 × 10-14 mag to 2.70 × 10-13 mag with mean value of 1.57 × 10-13 mag. The distribution trend of flux, dust color temperature, and Planck’s function are nearly similar, whereas dust mass and visual extinction follow an inverse relationship with the previous three parameters.

We studied dust environment such as flux, temperature, mass and inclination angle of the cavity structure around the C-rich Asymptotic giant branch star in 60 μm and 100 μm wavelengths band using Infrared Astronomical Survey. We observed the data of AGB star having IRAS name 01142+6306 corresponding to R.A.(J2000)= 01h 17m 33.504s and Dec.(J2000)= 630 22’ 4.98’.  Flexible image transport system image was downloaded from Sky View Observatory; we obtained the surrounding flux density using software Aladinv2.5.  The dust color average temperature and mass are found to be 25.08 K and  4.731026 kg (0.00024 Mʘ) respectively. The dust color temperature ranges from 18.76 ± 3.16 K to 33.21 ± 4.07 K.   The isolated cavity like structure around AGB star has extension 45.67 parsec and contraction 17.02 parsec was observed using detailed calculation. The core region is found to be edge-on having inclination angle 79.46o. BIBECHANA 16 (2019) 31-40

The dust properties in the interstellar medium play an important role in structure formation and extinction of highenergy radiation. This study performed an investigation of the physical properties like distribution of dust color temperature, Planck’s function, and dust mass of the cavity around the pulsar PSR J1240-4124 in the IRIS and the AKARI surveys. In our study, the dust color temperature in the IRIS survey is found to be in the range of 23.607 ± 0.012 K to 24.342 ± 0.012 K with an offset of 0.735 K. Such low offset temperature indicates that the isolated cavities are in thermal equilibrium. In the case of the AKARI survey, the dust temperature was found to be in the range of 16.123 ± 0.017 K to 18.802 ± 0.017 K with an offset of 2.679 K. The average dust mass in IRIS survey is found to be 2.1 × 10−4 M⊙ and that of the AKARI is 8.1× 10−4 M⊙. The size of the structure in the IRIS map is 14.62 pc × 6.24 pc and that of the AKARI map is 5.80 pc × 0.17 pc. The angle of inclination for the selected cavity region is found to be 73.330° in IRIS and that of AKARI is 110.260° . We have tried to present the relationship among the different physical parameters and compare the results in the IRIS and the AKARI surveys. Our findings are similar to those obtained in previous studies of other cavity structures around pulsars. This confirms the validity of the existing results for a new cavity around PSR J1240-4124.