J/A+A/684/A86 6.7GHz methanol maser flare in G11.497-1.485 (Bayandina+, 2024)
Star formation in G11.497-1.485:
Two-epoch VLA study of a 6.7 GHz methanol maser flare.
Bayandina O.S., Burns R.A., Caratti o Caratti A., Kurtz S.E., Moscadelli L.,
Shakhvorostova N.N., Sobolev A.M., Tanabe Y., Val'tts I.E., Yonekura Y.
<Astron. Astrophys. 684, A86 (2024)>
=2024A&A...684A..86B 2024A&A...684A..86B (SIMBAD/NED BibCode)
ADC_Keywords: Star Forming Region ; Masers ; Radio sources
Keywords: stars: evolution - stars: formation - stars: massive
Abstract:
Maser flares are of particular significance for the study of massive
star formation as they not only signal but also provide unique
insights into transient phenomena such as accretion bursts. With this
project, we aim to investigate the context of the ongoing 6.7 GHz
methanol maser flare in the little-known massive star forming region
G11.497-1.485. Two epoch of the Karl G. Jansky Very Large Array (VLA)
observations have been performed for 6.7GHz and 12GHz class II
methanol, and 22GHz water masers, as well as continuum at C, Ku, and
K-bands. The VLA overview revealed the presence of five distinct
radio-continuum sources (CM1-4 and N) in G11.497-1.485. The central
source CM1 is found to show signs of accretion disk fragmentation,
highlighted by the cm-continuum traced fragments, as well as to drive
a high-energy jet, the ends of which are marked by non-thermal knots
CM2 and CM3. CM1 showed a gradual flaring of methanol masers and
fading of a 22GHz water maser, which might be signalling an accretion
burst. The two remaining sources of the region, CM4 and N, revealed
one of the most compact jet and disk-jet systems found to date. The
obtained data revealed, for the first time, the structure of the
G11.497-1.485 region. The change in fluxes of the maser and continuum
emission confirmed a transient event and revealed its impact on
multiple sources in the region.
Description:
Position, integrated and peak flux density, and velocity of each of
the detected 6.7GHz and 12GHz methanol, and 22GHz watre maser spots
are listed. Note that we use the term "maser spots" to refer to maser
emissions detected in a single velocity channel of a data cube.
Objects:
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RA (2000) DE Designation(s)
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18 16 22.12 -19 41 27.3 [HMW2016] G011.497-01.485
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 75 375 Parameters of the 6.7GHz CH3OH maser
in G11.497-1.485 CM1
tablea2.dat 75 196 Parameters of the 12GHz CH3OH maser
in G11.497-1.485 CM1
tablea3.dat 75 217 Parameters of the 22GHz H2O maser
in G11.497-1.485 CM1
tablea4.dat 75 263 Parameters of the 22GHz H2O maser
in G11.497-1.485 CM4
tablea5.dat 75 36 Parameters of the 6.7GHz CH3OH maser
in G11.497-1.485 N
tablea6.dat 75 53 Parameters of the 22GHz H2O maser
in G11.497-1.485 N
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See also:
J/AJ/163/83 : G358.93-0.03 6.67-23.12GHz CH3OH maser parameters
(Bayandina+, 2022)
Byte-by-byte Description of file: tablea*.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Epoch Observation epoch
4- 5 I2 h RAh Hour of Right Ascension (J2000)
7- 8 I2 min RAm Minute of Right Ascension (J2000)
10- 16 F7.4 s RAs Second of Right Ascension (J2000)
18- 24 F7.5 s e_RAs Uncertainty in RAs
26 A1 --- DE- Sign of the Declination (J2000)
27- 28 I2 deg DEd Degree of Declination (J2000)
30- 31 I2 arcmin DEm Arcminute of Declination (J2000)
33- 39 F7.4 arcsec DEs Arcsecond of Declination (J2000)
41- 46 F6.4 arcsec e_DEs Uncertainty in DEs
47- 52 F6.2 Jy Int Integrated Flux in units of Jy
54- 57 F4.2 Jy e_Int Uncertainty in Int
59- 64 F6.2 Jy Flux Peak Flux in units of Jy/beam
66- 69 F4.2 Jy e_Flux Uncertainty in Peak
71- 75 F5.2 km/s Vel Velocity
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Acknowledgements:
Olga Bayandina, olga.bayandina(at)inaf.it
(End) Olga Bayandina [INAF, Italy], Patricia Vannier [CDS] 24-Jan-2024