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J/A+A/372/L41       NGC 2068/2071 protoclusters              (Motte+, 2001)

A SCUBA survey of the NGC 2068/2071 protoclusters. Motte F., Andre P., Ward-Thompson D., Bontemps S. <Astron. Astrophys. 372, L41 (2001)> =2001A&A...372L..41M
ADC_Keywords: Molecular clouds ; Photometry, infrared ; Radio continuum Keywords: ISM: clouds - ISM: structure - dust - stars: formation - stars: initial mass function - submillimeter Description: We report on a wide-field submillimeter continuum survey of the NGC 2068/2071 protoclusters in the Orion B cloud complex. We used the SCUBA bolometer array on JCMT to map a 32'x18' region in size (∼4pcx2pc) at 850 and 450 microns. Our survey shows that the dense cores mapped in CS(2-1) by Lada et al. (1991ApJ...368..432L) and labelled with LBS numbers break up into 82 small-scale (∼5000AU) fragments. The latter include 70 starless condensations, believed to be the immediate progenitors of accreting protostars, and 5 circumstellar envelopes/disks around protostars. The nature of the 7 remaining cloud fragments is unclear because their dust continuum emission is largely contaminated by line emission. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 91 82 Protocluster condensations identified in NGC 2068/2071
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 10 A10 --- Name Condensation name 12- 13 I2 h RAh Right ascension (J2000) 15- 16 I2 min RAm Right ascension (J2000) 18- 21 F4.1 s RAs *Right ascension (J2000) 23 A1 --- DE- Declination sign 24- 25 I2 deg DEd Declination (J2000) 27- 28 I2 arcmin DEm Declination (J2000) 30- 31 I2 arcsec DEs *Declination (J2000) 33- 37 I5 mJy Sint850 Integrated flux at 850 microns (350GHz) (1) 39- 43 I5 AU FWHM1 ? Deconvolved FWHM size (2) 44 A1 --- --- [x] 45- 49 I5 AU FWHM2 ? Deconvolved FWHM size (2) 50 A1 --- f_FWHM1 [u] u: unresolved 52 A1 --- l_Mass [<] Upper limit symbol 53- 56 F4.2 solMass Mass Condensation mass (3) 58- 60 F3.1 --- Sp+Index ? Submm spectral index (4) 62- 91 A30 --- Text Comments on the condensation
Note on RAs, DEs: The absolute positional accuracy is better than ∼5". Note (1): Integrated flux at 850 microns estimated (after background subtraction, see Motte et al., 1998A&A...336..150M) over an area twice the size of FWHM when convolved with the 13" beam. The absolute calibration uncertainty is ∼20%. The typical rms noise is ∼22mJy*2*[(FWHM2+HPBW2)/HPBW2]1/2. Note (2): Deconvolved FWHM size derived from a 2D-Gaussian fit to the 850microns map after background subtraction. Note (3): Mass derived from the 850 microns integrated flux, Sint850. Assumed dust temperature and opacity are Td=15K and kappa850=0.01cm2/g for starless condensations, Td=20-40K and kappa850=0.02cm2/g for protostellar envelopes. Note (4): Spectral index alpha450850 (where S(nu) ∝ nu^alpha) measured between 450 microns and 850 microns in an 18" beam at the position of each condensation without background subtraction. The typical error bar on alpha450850 is ±0.5. Since the background emission often dominates and has a spectral index of ∼4, we estimate that the intrinsic spectral indices of the condensations are lower than the values listed here by ∼1 on average.
Acknowledgements: Frederique Motte Philippe Andre
(End) Frederique Motte [Caltech], Patricia Bauer [CDS] 22-Jun-2001
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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