J/A+A/572/A21 H2O spectra of 29 nearby Class 0/I protostars (Mottram+, 2014)
Water in star-forming regions with Herschel (WISH).
V. The physical conditions in low-mass protostellar outflows revealed by
multi-transition water observations.
Mottram J.C., Kristensen L.E., van Dishoeck E.F., Bruderer S.,
San Jose-Garcia I., Karska A., Visser R., Santangelo G., Benz A.O.,
Bergin E.A., Caselli P., Herpin F., Hogerheijde M.R., Johnstone D.,
van Kempen T.A., Liseau R., Nisini B., Tafalla M., van der Tak F.F.S.,
Wyrowski F.
<Astron. Astrophys. 572, A21 (2014)>
=2014A&A...572A..21M 2014A&A...572A..21M
ADC_Keywords: YSOs ; Spectroscopy
Keywords: stars: formation - ISM: jets and outflows - ISM: molecules -
stars: protostars
Abstract:
Outflows are an important part of the star formation process as both
the result of ongoing active accretion and one of the main sources of
mechanical feedback on small scales. Water is the ideal tracer of
these effects because it is present in high abundance for the
conditions expected in various parts of the protostar, particularly
the outflow.
We constrain and quantify the physical conditions probed by water in
the outflow-jet system for Class 0 and I sources.
We present velocity-resolved Herschel HIFI spectra of multiple
water-transitions observed towards 29 nearby Class 0/I protostars as
part of the WISH guaranteed time key programme. The lines are
decomposed into different Gaussian components, with each component
related to one of three parts of the protostellar system; quiescent
envelope, cavity shock and spot shocks in the jet and at the base of
the outflow. We then use non-LTE radex models to constrain the
excitation conditions present in the two outflow-related components.
Description:
This sample was the target of a series of observations of gas-phase
water transitions with the Heterodyne Instrument for the Far-Infrared
(HIFI) on Herschel between March 2010 and October 2011. Three of the
Class I sources (IRAS3A, RCrA-IRS5A and HH100-IRS) were only observed
in the 557GHz H2O 110-101 line, which was presented for all
sources by Kristensen et al. (2012A&A...542A...8K 2012A&A...542A...8K). All other sources
were observed in between four and seven H216O transitions and
between one and four H218O transitions. Additional data from two
OT2 programmes, OT2rvisser2 and OT2evandish4, are also included to
augment the WISH data.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 94 30 Source parameters
sp/* . 202 Individual FITS spectra
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Cl [0I] Protostar evolution class (0 or I)
3- 17 A15 ---- Source Source mame
18 A1 --- f_Source [f] WISH position (1)
19 A1 --- n_Source [*] * when two sets of spectra
20- 21 I2 h RAh Right ascension (J2000)
23- 24 I2 min RAm Right ascension (J2000)
26- 29 F4.1 s RAs Right ascension (J2000)
31 A1 --- DE- Declination sign (J2000)
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 41 F4.1 arcsec DEs Declination (J2000)
43- 45 I3 pc Dist Distance (2)
47- 51 F5.1 km/s Vlsr LSR velocity (3)
53- 56 F4.1 Lsun Lbol Bolometric luminosity (4)
58- 60 I3 K Tbol Bolometric temperature (4)
62- 65 F4.1 Msun Menv Mass within the 10K radius (5)
67- 72 E6.2 Msun/yr.km/s FCO ?=- CO flux momentum [(Msun/yr)*(km/s)] (6)
74 A1 --- s1 [a] a: H2O 110-101 spectrum
available (sp/{Source}H2O110-101.fits)
76 A1 --- s2 [b] b: H2O 111-000 spectrum
available (sp/{Source}H2O111-000.fits)
78 A1 --- s3 [c] c: H2O 202-111 spectrum
available (sp/{Source}H2O202-111.fits)
80 A1 --- s4 [d] d: H2O 211-202 spectrum
available (sp/{Source}H2O211-202.fits)
82 A1 --- s5 [e] e: H2O 212-101 spectrum
available (sp/{Source}H2O212-101.fits)
84 A1 --- s6 [f] f: H2O 312-221 spectrum
available (sp/{Source}H2O312-221.fits)
86 A1 --- s7 [g] g: H2O 312-303 spectrum
available (sp/{Source}H2O312-303.fits)
88 A1 --- S1 [A] A: H218O 110-101 spectrum
available (sp/{Source}H218O_110-101.fits)
90 A1 --- S2 [B] B: H218O 111-000 spectrum
available (sp/{Source}H218O_111-000.fits)
92 A1 --- S3 [C] C: H218O 202-111 spectrum
available (sp/{Source}H218O_202-111.fits)
94 A1 --- S4 [D] DH218O 312-303 spectrum
available (sp/{Source}H218O_312-303.fits)
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Note (1): f: coordinates used in WISH. More accurate SMA coordinates of the
sources are 15:43:02.2-34:09:06.8 (IRAS 15398),
04:39:13.9+25:53:20.6 (TMR1) and
04:39:35.2+25:41:44.4 (TMC1A; Jorgensen et al., 2009A&A...507..861J 2009A&A...507..861J).
For IRAS 15398, these coordinates were observed in two settings as part of
the OT2 programme OT2.evandish_4.
Note (2): Taken from van Dishoeck et al. (2011PASP..123..138V 2011PASP..123..138V) with the
exception of sources in Serpens, where we use the distance determined using
VLBA observations by Dzib et al. (2010ApJ...718..610D 2010ApJ...718..610D).
Note (3): Obtained from ground-based C18O or C17O observations (Yildiz et
al. 2013A&A...556A..89Y 2013A&A...556A..89Y) with the exception of IRAS4A for which the value from
Kristensen et al. (2012A&A...542A...8K 2012A&A...542A...8K) is more consistent with our data.
Note (4): Measured using Herschel PACS data from the WISH and DIGIT key
programmes (Karska et al. 2013A&A...552A.141K 2013A&A...552A.141K).
Note (5): determined by Kristensen et al. (2012A&A...542A...8K 2012A&A...542A...8K) from dusty
modelling of the sources.
Note (6): Taken from Yildiz et al. (2014, submitted) for CO 3-2.
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Acknowledgements:
Joseph Mottram, mottram(at)strw.leidenuniv.nl
References:
Kristensen et al., Paper I 2011A&A...531L...1K 2011A&A...531L...1K
Kristensen et al., Paper II 2012A&A...542A...8K 2012A&A...542A...8K
Karska et al., Paper III 2013A&A...552A.141K 2013A&A...552A.141K
van der Tak et al., Paper IV 2013A&A...554A..83V 2013A&A...554A..83V
(End) Patricia Vannier [CDS] 21-Nov-2014