Display data from paper

Select data type:

ALV12 - The magnetic field of IRAS 16293-2422 as traced by shock-induced H₂O masers

Interferometry data

Short title: Alves et al. (2012)
Authors: Alves, F. O.Vlemmings, W. H. T.Girart, J. M.Torrelles, J. M.
Journal: Astronomy & Astrophysics, Volume 542, id.A14, 7 pp.
Bibcode:

Target type: Low_mass_SFR
Transitions: H2O_22

Abstract
Context. Shock-induced H₂O masers are important magnetic field tracers of very high density gas. Water masers are found in both high- and low-mass star-forming regions, and are a powerful tool for comparing magnetic field morphologies in both mass regimes. Aims: We present one of the first magnetic field determinations for the low-mass protostellar core IRAS 16293-2422 at volume densities as high as 10^8-10 cm^-3. Our goal is to determine wether the collapsing regime of this source is controlled by magnetic fields or other factors such as turbulence. Methods: We used the Very Large Array (VLA) to carry out spectropolarimetric observations of the 22 GHz Zeeman emission from H₂O masers. From the Stokes V line profile, we are then able to estimate the magnetic field strength in the dense regions around the protostar. Results: A blend of at least three maser features can be inferred from our relatively high spatial resolution data set (~0.1''), which is reproduced as a clear non-Gaussian line profile. The emission is very stable in terms of polarization fraction and position angle across the channels. The maser spots are aligned with some components of the complex outflow configuration of IRAS 16293-2422, and are excited in zones of compressed gas produced by shocks. The post-shock particle density is in the range of 1-3 x10⁹ cm^-3, consistent with typical water-maser pumping densities. Zeeman emission is produced by a very strong line-of-sight magnetic field (B ~ 113 mG). Conclusions: The magnetic field pressure derived from our data is comparable to the ram pressure of the outflow dynamics. This indicates that the magnetic field is energetically important to the dynamical evolution of IRAS 16293-2422.

Abstract

Context. Shock-induced H₂O masers are important magnetic field tracers of very high density gas. Water masers are found in both high- and low-mass star-forming regions, and are a powerful tool for comparing magnetic field morphologies in both mass regimes.
Aims: We present one of the first magnetic field determinations for the low-mass protostellar core IRAS 16293-2422 at volume densities as high as 10^8-10 cm^-3. Our goal is to determine wether the collapsing regime of this source is controlled by magnetic fields or other factors such as turbulence.
Methods: We used the Very Large Array (VLA) to carry out spectropolarimetric observations of the 22 GHz Zeeman emission from H₂O masers. From the Stokes V line profile, we are then able to estimate the magnetic field strength in the dense regions around the protostar.
Results: A blend of at least three maser features can be inferred from our relatively high spatial resolution data set (~0.1''), which is reproduced as a clear non-Gaussian line profile. The emission is very stable in terms of polarization fraction and position angle across the channels. The maser spots are aligned with some components of the complex outflow configuration of IRAS 16293-2422, and are excited in zones of compressed gas produced by shocks. The post-shock particle density is in the range of 1-3 x10⁹ cm^-3, consistent with typical water-maser pumping densities. Zeeman emission is produced by a very strong line-of-sight magnetic field (B ~ 113 mG).
Conclusions: The magnetic field pressure derived from our data is comparable to the ram pressure of the outflow dynamics. This indicates that the magnetic field is energetically important to the dynamical evolution of IRAS 16293-2422.

Download as: Table (CSV)
View as list of objects

Detection table from Alves et al. (2012)

Export table to csv

Hide / Show individual components

ID	Obs. RA	Obs. Dec	RA offset	Dec offset	l	b	Group id	#	Source name	Image	Descr.	Line	V_peak	F_peak	Telescope	Configuration	V_step	RMS	Beam	PA	Detection	Class	Dist. (parallax)	Date
	(J2000)	(J2000)	(mas)	(mas)	(deg.)	(deg.)						H₂O	(km/s)	(Jy/beam)			(km/s)	(mJy/beam)	(arcsec)	(deg.)	Yes/No		(kpc)
1	+16 32 22.8808	-24 28 36.487			353.935499	15.839205	G353.936+15.839		IRAS 16293-2422	Image	Descr	22 GHz;	5.7 .. 9.2	5 .. 168	NRAOVLA	extA	0.08	8.000	0.14 x 0.08	-5.7	+H₂O -CH₃OH I -CH₃OH II	SFR		2007 June 25-27
	+16 32 22.883	-24 28 36.495	31.8 mas	-7.8 mas	353.935503	15.839197		1	IRAS 16293-2422				5.7	23
	+16 32 22.8808	-24 28 36.487	-1.2 mas	0.2 mas	353.935499	15.839205		2	IRAS 16293-2422				7.4	168
	+16 32 22.8818	-24 28 36.493	13.8 mas	-5.8 mas	353.935500	15.839201		3	IRAS 16293-2422				9.2	5

DSS colored	2MASS colored	WISE colored
SDSS color	IRAC color I1,I2,I4	GLIMPSE 360
PACS color (70-160 um)	SPIRE color (250-500 um)	NVSS (1.4GHz)
ATLASGAL 870 um	ATLASGAL 870 um + Planck	Bolocam 1.1 mm
UKIDSS K Download UKIDSS K FITS	2MASS K Download 2MASS K FITS

select MAX(h2o_data_all.ra_hms) as ra_hms,MAX(h2o_data_all.dec_dms) as dec_dms,MAX(h2o_data_all.source_name) as source_name,MAX(h2o_data_all.ra) as ra,MAX(h2o_data_all.dec) as dec,MAX(h2o_data_all.l) as l,MAX(h2o_data_all.b) as b,MAX(h2o_data_all.grp) as grp,MAX(h2o_data_all.other_name) as other_name,MAX(h2o_data_all.other_desc) as other_desc,BOOL_OR(thermal) as thermal,MAX(h2o_data_all.line) as line,MAX(h2o_data_all.vrange) as vrange,MAX(h2o_data_all.vpeak) as vpeak,MAX(h2o_data_all.peak) as peak,MAX(h2o_data_all.fwhm) as fwhm,MAX(h2o_data_all.int) as int,MAX(h2o_data_all.rms) as rms,MAX(h2o_data_all.units) as units,MAX(h2o_data_all.units_rms) as units_rms,MAX(h2o_data_all.date_txt) as date_txt,MAX(h2o_data_all.telescope_ref) as telescope_ref,MAX(h2o_data_all.telescope_conf) as telescope_conf,MAX(h2o_data_all.v_step) as v_step,MAX(h2o_data_all.beam) as beam,MAX(h2o_data_all.beam_maj) as beam_maj,MAX(h2o_data_all.beam_min) as beam_min,MAX(h2o_data_all.beam_pa) as beam_pa,MAX(h2o_data_all.ref) as ref,MAX(h2o_data_all.list_ref) as list_ref,MAX(h2o_data_all.ascii) as ascii,MAX(h2o_data_all.url) as url,MAX(h2o_data_all.image) as image,MAX(h2o_data_all.image2) as image2,MAX(h2o_data_all.image3) as image3,MAX(h2o_data_all.descr) as descr,MAX(h2o_data_all.id) as id,BOOL_OR(mjy_flag) as mjy_flag,BOOL_OR(rms_mjy_flag) as rms_mjy_flag,MAX(h2o_data_all.dist) as dist,1 as dist_parallax,MAX(h2o_data_all.date_txt) as date_txt,MAX(line_det) as line_det,MAX(type) as type,MAX(simbad_types_cat) as simbad_types_cat FROM h2o_data_all  LEFT JOIN all_objects_withmet ON h2o_data_all.grp=all_objects_withmet.group_name LEFT JOIN object_categories ON all_objects_withmet.group_name = object_categories.group_name_cat AND object_categories.tbl_cat = 'all_objects_withmet' LEFT JOIN transitions ON h2o_data_all.line=transitions."Line"  WHERE ref ilike 'ALV12' AND detected=true AND hide=false GROUP BY ref

select h2o_data_all.ra_hms,h2o_data_all.dec_dms,h2o_data_all.source_name,h2o_data_all.ra,h2o_data_all.dec,h2o_data_all.l,h2o_data_all.b,h2o_data_all.grp,h2o_data_all.other_name,h2o_data_all.other_desc,h2o_data_all.thermal,h2o_data_all.line,h2o_data_all.vrange,h2o_data_all.vpeak,h2o_data_all.peak,h2o_data_all.fwhm,h2o_data_all.int,h2o_data_all.rms,h2o_data_all.units,h2o_data_all.units_rms,h2o_data_all.date_txt,h2o_data_all.telescope_ref,h2o_data_all.telescope_conf,h2o_data_all.v_step,h2o_data_all.beam,h2o_data_all.beam_maj,h2o_data_all.beam_min,h2o_data_all.beam_pa,h2o_data_all.ref,h2o_data_all.list_ref,h2o_data_all.ascii,h2o_data_all.url,h2o_data_all.image,h2o_data_all.image2,h2o_data_all.image3,h2o_data_all.descr,h2o_data_all.id,h2o_data_all.mjy_flag,h2o_data_all.rms_mjy_flag,h2o_data_all.dist,h2o_data_all.dist_parallax,h2o_data_all.date_txt,line_det,type,simbad_types_cat FROM h2o_data_all   LEFT JOIN all_objects_withmet ON h2o_data_all.grp=all_objects_withmet.group_name LEFT JOIN object_categories ON all_objects_withmet.group_name = object_categories.group_name_cat AND object_categories.tbl_cat = 'all_objects_withmet' LEFT JOIN transitions ON h2o_data_all.line=transitions."Line"  WHERE ref ilike 'ALV12' AND detected=true AND hide=false ORDER BY detected DESC,id

Display data from paper

ALV12 - The magnetic field of IRAS 16293-2422 as traced by shock-induced H2O masers

Interferometry data

View as list of objects

Detection table from Alves et al. (2012)

ALV12 - The magnetic field of IRAS 16293-2422 as traced by shock-induced H₂O masers