Dust Color Temperature Research Articles

Study of a Far Infrared Cavity Around a Post-Asymptotic Giant Branch Star at Galactic Latitude -0.1º

We present dust color temperature, Planck function and visual extinction distributions of a far infrared cavity FIC19+30 found to be located around post-AGB star namely AGB20+29 at the galactic plane. Minimum and maximum dust color temperature of the core region of the cavity was found to be (22.17±0.23) K and (22.41±0.29) K respectively with offset value 0.24 K which suggests that the cavity is isolated and stable. The product of dust color temperature and visual extinction was found to be in the order of 10-4 K mag. The distribution of Planck function along the extension (major diameter) and compression (minor diameter) was found to be non-uniform distribution. Specifically dust particles are oscillating in order to get dynamical equilibrium which may be the cause of grain temperature. It further suggests that the dust particles in the cavities might not be in the thermal equilibrium possibly due to pressure driven events of nearby AGB stars. There is continuous increase in flux density with increase in wavelength as in case of nebula which suggests that number density of dust particles increase according to the increase in wavelength and vice-versa.

Study of a Far Infrared Cavity at 60 μm and 100 μm IRAS Map around the Carbon-Rich AGB Star at Galactic Latitude 8.6°

In this paper, we discussed about the dusty environment of the far infrared cavity around the AGB star located at R.A. (J2000) =01h41m 01s and Dec (J2000) = 71° 04’ 00 9, lying within far infrared loop G125+09 6 in the far infrared IRAS maps. A cavity like structure (major diameter ∼2.55pc & minor diameter ∼0.77pc) is found to lie at R.A. (J2000) = 01h46m57.2s and DEC (J2000) = 71°24’57.1”, located at a distance ∼ 220pc from the star. We studied the distribution of flux density, dust color temperature, dust mass, visual extinction in the cavity. We further studied the distribution Planck function along extension and compression, distribution of dust color temperature along square of the major and minor diameters. The dust color temperature is found to lie in the range (19.7±1.25) K to (21.1±0.55)K which shows the cavity is isolated and stable. A possible explanation of the results will be discussed.

Infrared properties of planetary nebulae with [WR] and wels central stars

ABSTRACT We report the infrared (IR) properties of planetary nebulae (PNe) with Wolf–Rayet (WR) type and wels central stars known to date and compare them with the IR properties of a sample of PNe with H-rich central stars. We use near-, mid-, and far-IR photometric data from archives to derive the IR properties of PNe. We have constructed IR colour–colour diagrams of PNe using measurements from 2MASS, IRAS, WISE, and Akari bands. [WR] PNe have a larger near-IR emission from the hot dust component and also show a tendency for stronger 12 μm emission as compared to the other two groups. Cool asymptotic giant branch dust properties of all PNe are found to be similar. We derived the dust colour temperatures, dust masses, dust-to-gas mass ratios, IR luminosities, and IR excess (IRE) of PNe for these three groups. [WR] PNe and wels-PNe tend to have larger mean values for dust mass when compared to the third group. The average dust-to-gas mass ratio is found to be similar for the three groups of PNe. While there is a strong correlation of dust temperature and IR luminosity with the age for the three groups of PNe, the dust mass, dust-to-gas mass ratios, and IRE are found to be non-varying as the PNe evolve. [WR] PNe and wels-PNe show very similar distribution of excitation classes and also show similar distribution with Galactic latitude.

Study of dust color temperature and visual extinction distribution of a far infrared cavity at 60 and 100 µm IRAS map around the AGB star at galactic latitude 8.6⁰

The dust-grain structure in the far infrared region under IRAS (Infrared Astronomical Satellite) Survey was studied using sky view virtual observatory. In order to find the possible far infrared cavity, we used SIMBAD database. In this paper, we discuss about the dusty environment of a far infrared cavity around the AGB star located at R.A. (J2000) =01h 41m 01s and Dec (J2000) = 71o 04’ 00” lying within far infrared loop G125+09 in the far infrared IRAS maps. A cavity like structure (major diameter ∼ 2.55 pc & minor diameter ∼ 0.77 pc) is found to lie at R.A. (J2000)= 01h 46m 57.2s and DEC (J2000)= 71o 24’ 57.1”, located at a distance ∼ 220 pc from the star. We studied the distribution of flux density, dust color temperature, dust mass, inclination angle, visual extinction and FIR spectral distribution of the cavity. We further studied the distribution of Planck function along extension and compression. The dust color temperature is found to lie in the range (19.7±0.65) K to 21.1±0.35) K which shows the cavity is isolated and stable. Product of visual extinction and dust color temperature is found to be less than one. A possible explanation of the results will be discussed.
 BIBECHANA 17 (2020) 42-49

Study of Two Far Infrared Cavities Nearby Asymptotic Giant Branch Stars Under Infrared Astronomical Satellite Maps

Dust colour temperature, dust mass, visual extinction and Planck function with their distributions in the core region of two far infrared cavities (named FIC04+61 and FIC11-54) found within 3° of AGB stars namely AGB0409+6105 and AGB1105-5451 were studied. Dust colour temperature of the core region of the cavities was found to be (19.4 ± 0.93) K to (20.6 ± 0.65) K and (21.4 ± 0.51) K to (22.6 ± 0.23) K, respectively. The product of dust colour temperature and visual extinction was consistent in the order of 10-4. The contour maps showed that the low-temperature region has greater mass density and suggests that the distribution of dust mass is homogeneous and isotropic. The distribution of Planck function along with the extension (major diameter) and compression (minor diameter) found to be non-uniform distribution means dust particles were oscillating to get dynamical equilibrium. It further suggests that the dust particles in the cavities might not be in the thermal equilibrium possibly due to pressure-driven events of nearby AGB stars. A negative slope in the transition from 25 μm to 60 μm was our finding regarding far infrared spectral distribution in the cavities. It suggests that the number density of dust particles was less than expected in 60 μm regions.

Study of a Far Infrared Cavity around an AGB Star under Iras Survey at Galactic Latitude -1.6°

In this paper, we discuss about the physical properties of the dusty environment around the AGB star located at R.A. (J2000) = 06h 42m 02s and Dec (J2000) = 00° 53’ 00”, in the far infrared (60 and 100μm) IRAS maps. A cavity like structure (major diameter ∼ 2.5 pc & minor diameter ∼0.9 pc) is found to lie at R.A. (J2000) = 06h 41m 43.03s and DEC (J2000) = 01° 09’ 22.8”, located at a distance ∼ 405 pc from the star. By using contour map diagram, we studied the distribution of flux density, dust color temperature, dust mass and outflow mass in the cavity. The dust color temperature is found to lie in the range 21.4K to 21.9 K which shows the cavity is isolated and independently evolved. Such a low offset temperature variation shows that the star is stable and its life is long. Dust particles are less interacting and mean free path is large. The cavity may be in thermally pulsating phase. Product of dust color temperature and visual extinction is found to be less than one. A possible explanation of the results will be discussed.

An Infrared Survey of Isolated Nebular Structures at Galactic Latitudes 16.98° & 1.98° in ARAS map

Two isolated far infrared dust structures (∼2.61pc × 1.57pc and ∼82.99pc × 39.99pc) at galactic coordinates: (353.01°, 16.98°) and (18.42°, 1.98°), were selected. We adopted the distance of the first structure to be about 139 pc and that of the second structure to be 2.6 kpc. In this present work we have studied the flux density variation and calculated dust color temperature and mass profile of the dust and Jeans mass of the structures using the data reduction software ALADIN v9. Our aim was to test whether this region is star forming or not. We also calculated the size and inclination angle of our structures. The dust color temperature is found to lie in the range 20.75 K to 35.90 K for the first region and 22.52 K to 45.63 K for the second region. The total mass of gas for the first structure is found to be about 20.99 M☉ and Jeans mass is found to be 180.9 M☉, which is significantly greater than the total mass of the structure, suggesting no possibility of star formation activity for the first region. For the second region, the total mass of gas and the Jeans mass are found to be 5621.61 M☉ and 6005.04 M☉ respectively. The mass of the region is still significantly lesser than the Jeans mass. Thus, we conclude that this region is also probably not a star forming region. Also the study of inclination angle suggests that the three-dimensional shape of structures is non uniform and regularly shaped.

A Study of Far Infrared Cavity At -3.6° Galactic Latitude

We have present properties like inclination angle, dust color temperature and dust mass of core region in far infrared located nearby White dwarf WD2236+541.The size of cavity is 0.84 pc×0.51 pc. The cavity is formed by high pressure at the time of white dwarf formation. The dust color temperature varies from 22.42K to 27.43 K. The inclination angle of cavity is 54.2°. The position of white dwarf is found at R.A. J (2000)= 22h38m24s and Dec. J (2000)= +54°26m19s.

A study of four low-latitude ( $${\mid } l{\mid }<10^{\circ }$$ ∣ l ∣ < 10 ∘ ) far-infrared cavities

We present dust color temperature, dust mass, planck function and visual extinction distributions in the four low-latitude ( $$\mid l\mid <10^{\circ }$$ ) far-infrared cavities namely FIC01+55, FIC05+28, FIC06−05 and FIC06−01 which are found to be located within 0.5 $$^{\circ }$$ far-infrared loops G128−03, G182+00, G212−11 and G214−01, respectively. These cavities are located within $$3^{\circ }$$ of AGB stars ABG01+55, AGB05+28, AGB06−05 and PAGB181, respectively. The dust color temperature of the core region is found to lie in the range $$18.4\pm 1.2$$ to $$26.2\, \pm 1.7\hbox {K}$$ . The product of dust color temperature and visual extinction is found to be consistent. The contour maps showed that the low temperature region have greater mass density. The distribution of planck function along major and minor diameters is found to be sinusoidal, suggesting oscillation in the grain temperature distribution.

Study of far infrared cavity around a post AGB star under IRAS survey at galactic latitude -3&amp;deg;

A systematic search of dust structure in the far infrared (100 μm and 60 μm) under Infrared Astronomical Satellite (IRAS) survey was performed using Sky View virtual Observatory. In order to find the possible candidate of cavity structure not yet studied, we used SIMBAD database to locate discrete sources in the region. A new relatively symmetric spherical cavity like structure (size: 1.354 pc x 0.971 pc) at R.A.(J2000) =08h 03m 01.65s, Dec.(J2000) = -360 35' 47.9" was found at the distance of about 2800 pc. In this article, we have calculated dust color temperature, dust mass and size. We also studied the flux density variation and then calculated temperature and mass profile of the dust of p-AGB star using data reduction software Aladin2.5 and Aladin8.0. We have studied a cavity like structure centered at R.A.(J2000) = 08h 04m 07.21s, Dec.(J2000) = -370 11' 48.0". The dust color temperature is found to lie in the range 21.6 ± 0.09 K to 22.5 ± 0.05 K with an offset of 0.9 K. Such low off set suggests that the post AGB is in local thermodynamic equilibrium. The total mass of the dust in the cavity structure is found about 5.93 x 1025 Kg (0.00003M⊙)BIBECHANA 1 6 (2019) 23-30

Study of ambient environment around Asymptotic Giant Branch Carbon Star: IRAS 01142+6306

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

Dust Structure Around Asymptotic Giant Branch Stars

AbstractThis 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.

Cosmic-rays, gas, and dust in nearby anti-centre clouds

Aims. We have explored the capabilities of dust extinction and γ rays to probe the properties of the interstellar medium in the nearby anti-centre region. In particular, we aim at quantifying the variations of the dust properties per gas nucleon across the different gas phases and different clouds. The comparison of dust extinction and emission properties with other physical quantities of large grains (emission spectral index β, dust colour temperature Tdust, total-to-selective extinction factor RV) helps the theoretical modelling of grains as they evolve from diffuse to dense cloud environments. Methods. We have jointly modelled the γ-ray intensity, recorded between 0.4 and 100 GeV with the Fermi Large Area Telescope (LAT), and the stellar reddening, E(B − V), inferred from Pan-STARRS and 2MASS photometry, as a combination of HI-bright, CO-bright, and ionised gas components. The complementary information from dust reddening and γ rays is used to reveal the gas not seen, or poorly traced, by HI, free-free, and 12CO emissions, namely (i) the opaque HI and diffuse H2 present in the dark neutral medium (DNM) at the atomic-molecular transition, and (ii) the dense H2 to be added where 12CO lines saturate (COsat). We compare the total gas column densities, NH, derived from the γ rays and stellar reddening with those inferred from a similar, previously published analysis of γ rays and of the optical depth of the thermal dust emission, τ353, at 353 GHz. We can therefore compare environmental variations in specific dust reddening, E(B − V)∕NH, and in dust emission opacity (dust optical depth per gas nucleon), τ353∕NH. Results. The gas column densities obtained when combining γ rays with either dust reddening or dust emission compare reasonably well in the atomic and DNM gas phases and over most of the CO-bright phase, but we find localised differences in the dense media (COsat component) due to differences in the two dust tracers. Over the whole anti-centre region, we find an average E(B − V)∕NH ratio of (2.02 ± 0.48) ×10−22 mag cm2, with maximum local variations of about ± 30% at variance with the two to six fold coincident increase seen in emission opacity as the gas column density increases. We show how the specific reddening and opacity vary with the colour temperature and spectral index of the thermal emission of the large grains. Additionally, we find a better agreement between the XCO = N(H2)/WCO conversion factors derived with dust reddening or with γ rays than with those inferred from dust emission, especially towards clouds with large τ353 optical depths. The comparison confirms that the high XCO values found with dust emission are biased by the significant rise in emission opacity inside molecular clouds. Conclusions. In the diffuse medium, we find only small variations in specific reddening, E(B − V)∕NH, compatible with the dispersion in the RV factor reported by other studies. This implies a relatively uniform dust-to-gas mass ratio in the diffuse parts of the anti-centre clouds. The small amplitude of the E(B − V)∕NH variations with increasing NH column density confirms that the large opacity τ353∕NH rise seen towards dense CO clouds is primarily due to changes in dust emissivity. The environmental changes are qualitatively compatible with model predictions based on mantle accretion on the grains and the formation of grain aggregates.

Dust color temperature distribution of two FIR cavities at IRIS and AKARI maps

By systematically searching the region of far infrared loops, we found a number of huge cavity-like dust structures at $$60\,\mu \hbox {m}$$ and $$100\,\mu \hbox {m}$$ IRIS maps. By checking these with AKARI maps ( $$90\,\mu \hbox {m}$$ and $$140\,\mu \hbox {m}$$ ), two new cavity-like structures (sizes $$\sim $$ $$ 2.7\,\hbox {pc} \times 0.8\,\hbox {pc}$$ and $$\sim $$ $$ 1.8\,\hbox {pc} \times 1\,\hbox {pc}$$ ) located at R.A. ( $$\hbox {J}2000)=14^{h}41^{m}23^{s}$$ and Dec. $$(\hbox {J}2000)=-64^{\circ }04^{\prime }17^{{\prime }{\prime }}$$ and R.A. $$(\hbox {J}2000)=05^{h}05^{m}35^{s}$$ and Dec. $$(\hbox {J}2000)=-\,69^{\circ }35^{\prime } 25^{{\prime }{\prime }}$$ were selected for the study. The difference in the average dust color temperatures calculated using IRIS and AKARI maps of the cavity candidates were found to be $$3.2\pm 0.9\,\hbox {K}$$ and $$4.1\pm 1.2\,\hbox {K}$$ , respectively. Interestingly, the longer wavelength AKARI map gives larger values of dust color temperature than that of the shorter wavelength IRIS maps. Possible explanation of the results will be presented.

Physical properties of dust particles around white dwarf in far infrared sky at 12.8o galactic latitude

We study the active region in the interstellar medium in which the process of cavity formation is expected. The interaction between wind and its surroundings in the interstellar medium (ISM) provides a laboratory to study the behavior of dust particles. The information obtained from the dust colour temperature and dust mass of WD2116+675 will be presented. It is found that the dust colour temperature and dust mass lie in the range 20 K to 22.3 K and 2.1×1023 kg to 2.9×1023 kg respectively. With the help of number density, flux density, dust colour temperature and dust mass maps, the variation of temperature and mass in different position of dust will be presented and discussed. BIBECHANA 15 (2018) 43-49

A study of far infrared loop at -5o galactic latitude around pulsar J1627-5547

We present physical properties of the core region of infrared loop G329-05 which is found to be located within 1o from the pulsar PSR J1627-5547. The loop has 3-fold reduced flux density than its surroundings. In the 100 micron infrared map, a new cavity-like isolated far infrared dust structure of core region (size ~0.750 x 0.230 ) is found at R.A. (J2000)= 16h 27m 19.9s &amp; Dec. (J2000) = -56035’14”. This loop is believed to be formed because of high pressure events occurred in the past. The dust color temperature of the core region is found to lie in the range 25.26 ± 0.09 K to 27.91 ± 0.09 K, whereas the value of dust color temperature increased to 36.72 ± 0.18 K for the outer region. The dust color temperature and dust mass distribution maps showed that the low temperature region has greater density as expected. The dust mass of the core region of the loop is found to be 1.67 x 1027 kg i.e. about 0.00835 Mʘ. The core region of the loop is found to be edge-on (i ˃780) whereas the larger structure is faced-on (i =00). Possible explanation of results will be presented.BIBECHANA 15 (2018) 70-76

Far infrared cavity of a post C-rich AGB star under IRAS survey

In this paper, we discuss about the physical properties of the dusty environment around the mass losing carbon rich post AGB star located at R.A. (J2000) =06 h 53m 01s and Dec (J2000) =-02o 16’ 00”, in the far infrared IRAS maps. A cavity like structure (major diameter ∼ 103.3 pc &amp; minor diameter ∼33.1 pc) is found to lie at R.A. (J2000)= 06 h 51 m 54.02 s and DEC (J2000) = -01o 35’ 43”, located at a distance ∼ 6.11 kpc from the star. We studied the distribution of flux density, dust color temperature, dust mass in the cavity. The dust color temperature is found to lie in the range 18.7 K to 20.5 K which shows the cavity is isolated and independently evolved. Such a low offset temperature variation shows that there is symmetric outflow or symmetric distribution of density and temperature. It further suggests that our structure is bigger in size and is far away from the far infrared loops(kk loops). The cavity may be in thermally pulsating phase. A possible explanation of the results will be discussed.BIBECHANA 90 (2018) 96

Dust Structure around two Asymptotic Giant Stars at Latitude 32&amp;deg; &amp; 40.67&amp;deg;

We studied the dust structures in 60μm and 100μm infrared image around the two asymptotic giant branch (AGB) stars. A systematic search of dust structure in the far infrared (100 μm and 60 μm) Infrared Astronomical Satellite (IRAS) survey was performed using Sky View Observatory. In order to find the possible candidate of cavity structure not yet studied, we used SIMBAD database to locate discrete sources in the region. A new relatively symmetric spherical cavity like structure (size: 1.354 pc × 0.971 pc) for candidate I and (size: 1.424 pc × 0.925pc) for candidate II at R.A.(J2000) =04h46m13.84s, Dec.(J2000) = +32°31’39.6’’ and 05h05m59.58s; +40°40’33.4’’ respectively was found at the distance of about 280 pc and 390 pc. In this present work we have calculated the dust color temperature, mass, outflow velocity, energy and size. We also studied the flux density variation and then calculated temperature and mass profile of the dust and outflow nature of AGB wind using data reduction software’s Aladin v2.5 and Aladinv8.0. Our aim was to test how outflow can be seen in this region. We have studied two cavity-like structures. The dust color temperature is found to lie in the range 21.7 K to 35.6 K for candidate I and 18.5 K to 19.3 K, with an offset of about 14 K and 0.8 K respectively. An offset of 14 K suggests that the AGB is hot in early AGB phase now in late AGB stage. We expect deviation from symmetrical outflow, i.e., AGB wind probably prefer polytropic behaviour implies bipolar type wind whereas the offset 0.8 K for candidate II suggests that the AGB is in the symmetric AGB phase, i.e., early AGB stage. The total mass of the dust in the cavity structure is found about 5.93×1025 Kg (0.00003Mʘ) for candidate I and 1.95×1027Kg (0.001 Mʘ) for candidate II. In addition we have calculated outflow energy of C-rich AGB star along ISM using outflow velocity of our candidates. It is found that the outflow velocities are 12.96 ms-1 and 10.71 ms-1 respectively. For this we have calculated the value of speed of sound (Cs) and escape velocity (uesc). In this way we have determined outflow energy, i.e., 1.173×1025J and 2.766 × 1027J respectively.The Himalayan Physics Vol. 6 &amp; 7, April 2017 (41-47)

Study of Far Infrared Nebula at Declination +53° (J2000) In Iras Map

In this present work we studied the flux density variation, calculate temperature, dust mass and finally Jean’s mass of structure using data reduction software ALADIN2.5. Our aim was to test whether this region is star forming or not. Sky view observatory was used for the search of isolated nebular structure in the far infrared (100 μm and 60 μm) in IRAS (Infrared Astronomical Satellite) catalogue. Stellarium software was used to find coordinate of the structure. A far infrared dust structure (about ~ 11.99 × 3.14 pc.) at Right Ascension (J2000):01h 51m 56.02s Declination (J2000): +53deg 27m 39.0s found at the distance of about 550 pc. The dust color temperature was found to lie in the range 18.02 K to 39.56 K. An offset of about 21 K suggests that the structure is not independently evolved, discrete source may play significant role in structure formation mechanisms. The study of flux variation along major and minor axis of structure showed that mass is concentrate at the center of structure. The total mass of the gas structure was found to be about 1.1432× 1031Kg. The Jeans mass was found to be 1.17 x 1033Kg, more than that of the total mass of the structure, suggest no clue of star formation.The Himalayan Physics Vol. 6 &amp; 7, April 2017 (76-79)

A CO survey on a sample ofHerschelcold clumps

The physical state of cold cloud clumps has a great impact on the process and efficiency of star formation and the masses of the forming stars inside these objects. The sub-millimetre survey of the Planck space observatory and the far-infrared follow-up mapping of the Herschel space telescope provide an unbiased, large sample of these cold objects. We have observed $^{12}$CO(1$-$0) and $^{13}$CO(1$-$0) emission in 35 clumps in 26 Herschel fields sampling different environments in the Galaxy. Densities and temperatures were calculated from both the dust continuum and the molecular line data, kinematic distances were derived using $^{13}$CO line velocities and clump sizes and masses were calculated by fitting 2D Gaussian functions to the optical depth distribution maps. Clump masses and virial masses were estimated assuming an upper and lower limit on the kinetic temperatures and considering uncertainties due to distance limitations. The excitation temperatures are between 8.5$-$19.5 K, while the Herschel-derived dust colour temperatures are 12$-$16 K. The sizes (0.1$-$3 pc), $^{13}$CO column densities (0.5$-$44$\times$10$^{15}$ cm$^{-2}$) and masses (from less than 0.1 $M_{\odot}$ to more than 1500 $M_{\odot}$) of the objects span broad ranges. Eleven gravitationally unbound clumps were found, many of them smaller than 0.3 pc, but large, parsec-scale clouds with a few hundred solar masses appear as well. Colder clumps have generally high column densities but warmer objects appear at both low and higher column densities. The clump column densities derived from the line and dust observations correlate well, but are heavily affected by uncertainties of the dust properties, varying molecular abundances and optical depth effects.