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J/ApJ/699/742      Properties of cores in the Pipe Nebula     (Rathborne+, 2009)

Dense cores in the Pipe Nebula: an improved core mass function. Rathborne J.M., Lada C.J., Muench A.A., Alves J.F., Kainulainen J., Lombardi M. <Astrophys. J., 699, 742-753 (2009)> =2009ApJ...699..742R
ADC_Keywords: Molecular clouds ; Extinction Keywords: dust, extinction - ISM: globules - ISM: molecules - stars: formation - stars: luminosity function, mass function Abstract: In this paper, we derive an improved core mass function (CMF) for the Pipe Nebula from a detailed comparison between measurements of visual extinction and molecular-line emission. We have compiled a refined sample of 201 dense cores toward the Pipe Nebula using a two-dimensional threshold identification algorithm informed by recent simulations of dense core populations. Measurements of radial velocities using complimentary C18O(1-0) observations enable us to cull out from this sample those 43 extinction peaks that are either not associated with dense gas or are not physically associated with the Pipe Nebula. Moreover, we use the derived C18O central velocities to differentiate between single cores with internal structure and blends of two or more physically distinct cores, superposed along the same line of sight. We then are able to produce a more robust dense core sample for future follow-up studies and a more reliable CMF than was possible previously. Description: Observations of C18O(1-0) molecular line emission toward all 201 extinction peaks identified toward the Pipe Nebula were obtained using the 12m Arizona Radio Observatory (ARO) and the 22m Mopra telescopes. The ARO C18O(1-0) observations were conducted over two periods in 2005-2006. In total, 102 of the 201 extinction peaks were observed with the ARO. Ninety-four of these positions corresponded to cores within the original list of Alves et al. (2007, Cat. J/A+A/462/L17). The details of these observations are presented in Muench et al. (2007ApJ...671.1820M). Spectra were obtained with the Mopra telescope toward all remaining identified extinction peaks for which we had no previous C18O(1-0) data. In total, an additional 99 positions were observed over the periods 2007 July 3-8 and 2008 July 20-25. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 59 134 Core properties
See also: J/A+A/462/L17 : Dense cores in interstellar molecular clouds (Alves+, 2007) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 3 I3 --- [RLM2009] Core identification number 5 A1 --- f_[RLM2009] [b] b means extinction peaks were merged within this core 7- 11 F5.2 deg GLON Galactic longitude in decimal degrees 13- 16 F4.2 deg GLAT Galactic latitude in decimal degrees 18- 21 F4.1 mag Av Peak extinction 23- 26 F4.2 pc Rad Radius in parsec 28- 31 F4.1 Msun Mass Mass of the core 33- 35 F3.1 10+4cm-3 nH2 H2 density 37- 40 F4.2 K T*A Peak antenna temperature 42- 45 F4.2 km/s vLSR LSR velocity 47- 50 F4.2 km/s dV Velocity difference (δV) between each extinction peak and all others in a larger extinction feature (see figure 3) 52- 59 A8 --- A07 Alves et al. 2007 core(s) (1)
Note (1): Core number from the catalog of Alves et al. 2007 (A07; Cat. J/A+A/462/L17; <[ALL2007] NNN> in Simbad); 33 cores from the A07 catalog are not included here because they either had no associated C18O(1-0) emission or the C18O(1-0) emission was not in the range 2<vLSR<8km/s. Because of the differences in the way the cores were extracted from the extinction image and the fact that we merged or separated the extinction based on the associated C18O(1-0) emission, many of the cores from A07 are listed multiple times in our catalog. To be associated with a core in the current catalog, we require the cores of A07 to have more than 20 pixels contained within the boundary of the new core. This criteria was necessary to prevent entries where the cores within the two catalogs overlapped only at the very edges.
History: From electronic version of the journal
(End) Emmanuelle Perret [CDS] 05-Jul-2011
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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