The BIMA Embedded Cores Survey was designed toinvestigate various aspects of early star formation andcomplement the SIRTF c2d Legacy Project.
Proposal approved in Fall 2000; observations completed in Spring 2002.
Survey targets:Eighteen embedded cores in the Perseus Clouds, selected from the databaseof NH
3 cores by Jijina, Myers, & Adams 1999. Three additional cores from
the survey by Looney et al.
NGC 1333: IRAS2, IRAS4, IRAS8, IRAS9,L1448 IRS3 (N, C), L1448 IRS2,L1455 A1, A2, B, C,Per 4N, Per 4S, Per 5, Per 6, Per 7E, Per7W, Per9W,B1S, B5, IRAS 03282+3035
Range of luminosities: ~1L < L < ~200LRange of masses: <1M < M < ~13M
The Perseus Molecular Cloud Complex in 13CO (J=1- 0), from Padoan et al. 1999.
The Perseus Molecular Cloud Complex
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Array configurations: B, C, D (angular resolutions of ~2", 6", and 14")
Continuum emission and molecular line data:C18O J=1- 0 (109.8 GHz), 13CO J=1- 0 (110.2 GHz).
Supplementary observations:with BIMA: N
2H+ J=1- 0 (93.2 GHz), H13CO+ J=1- 0 (86.8 GHz)
with FCRAO (14m antenna, resolution ~45"): C18O, N2H+
Scientific Objectives for the Key Project data:
Examining Envelope Structure:Power law description of mass distribution;
robustness of R- 2 dependence found by Looney.Correlation of envelope structure with observed luminosity.
Exploring the Extent of Molecular Depletion:Models that reproduce observed C18O line profiles require
reduced abundances.
Analyzing the Velocity Fields:Few published maps of velocity fields with high spatial resolution.Correlation of angular momentum distribution with stellar multiplicity
(revealed by SIRTF).
Tracing the Formation of Circumstellar Disks:Looney showed that disks in embedded sources cannot have more mass
than the envelope distribution extrapolated to small scales.SIRTF will be sensitive to presence of hot central disks.
100% of proposed tracks have beenobserved with passing grades.
100% of datasets have been reduced.
100% of embedded cores have beenobserved in C18O and N
2H+ with the
FCRAO 14m antenna.
With the 3 pre- Key Project objects(IRAS2, IRAS4, L1448N), the`bottleneck' was determining theoptimal method for combiningthe BIMA and FCRAO observations.The method has now been stream-lined.
Barnard5 IRS1
Colorscale:=3mm emission
RMS noise in continuum:1.4 mJy/bm
Contours:C18O (J=1- 0)integrated intensity
RMS noise in C18O:~55 mJy/bm in km/s
Plus symbols:2MASS point sources
InventoryNAME IRAS PSC 3mm C18O 2MASS in PbeamIRAS2 03258+3104 2 y 49IRAS4 03259+3105 3 y 10IRAS8 03260+3111 1 (2?) y 36IRAS9 03262+3114 1 y 23L1448N 03225+3034 2 y 18L1448C 1 y 12L1448 IRS2 03222+3034 2 y 4L1455A1 03245+3002 2 y 21L1455A2 03247+3001 0 (weak?) y 25L1455B 03249+2957 0 (weak?) y 20L1455C 0 y 16Per4N 03262+3123 1 y 14Per4S 1 y 17Per5 03267+3128 1 y 10Per6 1 (offset?) n (offset?) 5Per7E 0 y 2Per7W 0 y 3Per9W 0 y 3B1S 03301+3057 2 y 5B5 IRS1 03445+3242 1 y 7I03282 03282+3035 1 y 4
Observations revealfewer continuum sourcesthan expected.(No rich fields ofembedded sources.)
Uncertainties in thepositions of the IRASsources persist. Theseshould be dispelledby SIRTF observations.
NGC1333 IRAS2, IRAS4; L1448 NC18O J=1- 0 integrated intensity;
BIMA + FCRAO combined;resolution ~10"
Integrated Intensity (0th moment) Map,contours = 3,6,8,9,10,11,12,13,14
x 0.46 Jy/bm
Integrated Intensity (0th moment) Map,contours = 3,6,9,10,11,12,13,14
x 0.35 Jy/bm
Integrated Intensity (0th moment) Map,contours = 3,6,9,10,11,12
x 0.54 Jy/bm
NGC1333 IRAS2 NGC1333 IRAS4 L1448 N