<sup>13</sup>CH<sub>3</sub>OH Masers Associated With a Transient Phenomenon in a High-mass Young Stellar Object

Chen, Xi; Соболев, А. М.; Breen, S. L.; Shen, Zhi; Ellingsen, S. P.; MacLeod, G. C.; Li, Bin; Voronkov, Maxim; Kaczmarek, Jane; Zhang, J. S.; Ren, Zhi Yuan; Wang, Jin; Linz, H.; Hunter, T. R.; Brogan, C. L.; Sugiyama, Koichiro; Burns, Ross; Menten, K. M.; Sanna, A.; Stecklum, B.; Hirota, Tomoya; Kim, Kee‐Tae; Chibueze, James O.; Heever, Sp Van Den

doi:10.3847/2041-8213/ab72a5

Cited by 38 publications

(17 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A similar 6.7 GHz CH 3 OH maser flare was also detected in NGC6334I-MM1 (Hunter et al 2018;MacLeod et al 2018), along with a 22 GHz water (H 2 O) maser burst (Brogan et al 2018). Another HMYSO G358.93-0.03-MM1 (Sugiyama et al 2019;Burns et al 2020) showed a flare of the 6.7 GHz CH 3 OH masers and other new methanol transitions (Breen et al 2019;Brogan et al 2019;MacLeod et al 2019;Chen et al 2020), a result of the recent extensive observations by the global collaboration network "Maser Monitoring Organization" (M2O; MaserMonitoring.org). The outbursts from these HMYSOs represent a unique opportunity to investigate the accretion and, in turn, ejection processes in these objects and derive useful parameters, such as the mass accretion and ejection rates, infall velocity, and duration of the events.…”

Section: Introductionmentioning

confidence: 78%

Water maser variability in a high-mass YSO outburst -- VERA and ALMA observations of S255 NIRS 3

Hirota,

Cesaroni,

Moscadelli

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

Context. Clarifying the relationship between mass accretion and ejection history is one of the key issues in understanding high-mass star-formation processes. Aims. We aim to investigate the possible relationship between the mass accretion burst event in mid-June 2015 and the outflow/jet ejection in the high-mass protostar S255 NIRS 3. Methods. We have carried out monitoring observations of the 22 GHz H 2 O masers by using the Japanese very long baseline interferometer (VLBI), VLBI Exploration of Radio Astrometry (VERA), to reveal the 3-dimensional velocity and spatial structure of the outflow/jet traced by the H 2 O masers in S255 NIRS 3. In addition, we have conducted followup observations of the submillimeter continuum and the 321 GHz H 2 O masers with Atacama Large Millimeter/submillimeter Array (ALMA) at Band 7. Results. We successfully measured the proper motions of the 22 GHz H 2 O masers associated with a bipolar outflow. The structure is almost the same as observed in 2005 and 2010. The expansion velocity of the blueshifted bow shock traced by the 22 GHz H 2 O masers was measured to be 28 km s −1 corresponding to a dynamical timescale of 60 years. The direction of the maser outflow is slightly tilted compared with the radio jet, which could suggest a more recent ejection episode during the accretion burst event. The total flux density of the 22 GHz H 2 O masers has gradually increased from the beginning of the VLBI monitoring in early 2017 and has become almost constant in subsequent single-dish monitoring in 2018. The brightening of the H 2 O masers is more prominent in the northeast outflow lobe. For the first time, we reveal extended H 2 O maser emission at 22 GHz in a star forming region, which is partly resolved out by VERA and even by the most extended Very Large Array (VLA) configurations. We find that the flux variation of such an extended component is similar to that of the unresolved maser emission. The ALMA Band 7 continuum emission does not show significant variations compared with the previous observations performed 5 months before. We mapped the 321 GHz H 2 O masers in S255 NIRS 3 providing the fourth example, for this maser, of the spatial distribution in a high-mass star-forming region. Conclusions. We conclude that the bow shock structure traced by the 22 GHz H 2 O maser features is unlikely to be originating at the interface between the radio jet powered by the recent accretion outburst and the surrounding medium. The brightening of the 22 GHz H 2 O masers could be due to radiative excitation by photons form the (declining) infrared outburst escaping along the cavity created by the newly ejected material. The lower ratio of the 22 GHz/321 GHz maser luminosity in the blueshifted bow shock suggests a temperature (>1000 K), higher than for the other maser features in this region.

show abstract

Section: Introductionmentioning

confidence: 78%

Water maser variability in a high-mass YSO outburst -- VERA and ALMA observations of S255 NIRS 3

Hirota,

Cesaroni,

Moscadelli

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…Note that the only centimetre observations found in the literature on the pre-burst epoch are those of Hu et al (2016), who report a null detection at C-band, but based on only 20 seconds of data. The latest VLA B-array observation of Chen et al (2020a) also reported a non-detection of Ku-band continuum emission in the direction of MM1 at 3σ level of 20 µJy.…”

Section: Continuum Emissionmentioning

confidence: 98%

A multi-transition methanol maser study of the accretion burst source G358.93-0.03-MM1

Bayandina,

Brogan,

Burns

et al. 2022

Preprint

View full text Add to dashboard Cite

We present the most complete to date interferometric study of the centimeter wavelength methanol masers detected in G358.93−0.03 at the burst and post-burst epochs. A unique, NIR/(sub)mmdark and FIR-loud MYSO accretion burst was recently discovered in G358.93−0.03. The event was accompanied by flares of an unprecedented number of rare methanol maser transitions. The first images of three of the newly-discovered methanol masers at 6. 18, 12.23, and 20.97 GHz are presented in this work. The spatial structure evolution of the methanol masers at 6.67, 12.18, and 23.12 GHz is studied at two epochs. The maser emission in all detected transitions resides in a region of ∼0.2 around the bursting source and shows a clear velocity gradient in the north-south direction, with redshifted features to the north and blue-shifted features to the south. A drastic change in the spatial morphology of the masing region is found: a dense and compact "spiral" cluster detected at epoch I evolved into a disperse, "round" structure at epoch II. During the transition from the first epoch to the second, the region traced by masers expanded. The comparison of our results with the complementary VLA, VLBI, SMA, and ALMA maser data is conducted. The obtained methanol maser data support the hypothesis of the presence of spiral-arm structures within the accretion disk, which was suggested in previous studies of the source.

show abstract

“…All these findings suggest the impact of the outflow/jet to the ambient gas around W42-MME, which is an IRc of the 6.7 GHz MME. Recently, flaring methanol masers have been found to trace episodic accretion events in young protostars (e.g., Bertout 1989;Hirota et al 2018;Hunter et al 2018;MacLeod et al 2018;Chen et al 2020;Liu et al 2020;Zinchenko et al 2020;Stecklum et al 2021). Hence, our findings appear to show the episodic ejection from W42-MME.…”

Section: Signature Of An Episodic Accretion Processmentioning

confidence: 99%

The disk-outflow system around the rare young O-type protostar W42-MME

Dewangan,

Zinchenko,

Zemlyanukha

et al. 2021

Preprint

View full text Add to dashboard Cite

We present line and continuum observations (resolution ∼0. 3-3. 5) made with the Atacama Large Millimeter/submillimeter Array (ALMA), Submillimeter Array, and Very Large Array of a young O-type protostar W42-MME (mass: 19±4 M ). The ALMA 1.35 mm continuum map (resolution ∼1 ) shows that W42-MME is embedded in one of the cores (i.e., MM1) located within a thermally supercritical filament-like feature (extent ∼0.15 pc) containing three cores (mass ∼1-4.4 M ). Several dense/hot gas tracers are detected toward MM1, suggesting the presence of a hot molecular core with the gas temperature of ∼38-220 K. The ALMA 865 µm continuum map (resolution ∼0. 3) reveals at least five continuum sources/peaks ("A-E") within a dusty envelope (extent ∼9000 AU) toward MM1, where shocks are traced in the SiO(8-7) emission. The source "A" associated with W42-MME is seen almost at the center of the dusty envelope, and is surrounded by other continuum peaks. The ALMA CO(3-2) and SiO(8-7) line observations show the bipolar outflow extended below 10000 AU, which is driven by the source "A". The ALMA data hint the episodic ejections from W42-MME. A disk-like feature (extent ∼2000 AU; mass ∼1 M ) with velocity gradients is investigated in the source "A" (dynamical mass ∼9 M ) using the ALMA H 13 CO + emission, and is perpendicular to the CO outflow. A small-scale feature (below 3000 AU) probably heated by UV radiation from the O-type star is also investigated toward the source "A". Overall, W42-MME appears to gain mass from its disk and the dusty envelope.

show abstract

¹³CH₃OH Masers Associated With a Transient Phenomenon in a High-mass Young Stellar Object

Cited by 38 publications

References 31 publications

Water maser variability in a high-mass YSO outburst -- VERA and ALMA observations of S255 NIRS 3

Water maser variability in a high-mass YSO outburst -- VERA and ALMA observations of S255 NIRS 3

A multi-transition methanol maser study of the accretion burst source G358.93-0.03-MM1

The disk-outflow system around the rare young O-type protostar W42-MME

Contact Info

Product

Resources

About

13CH3OH Masers Associated With a Transient Phenomenon in a High-mass Young Stellar Object

Cited by 38 publications

References 31 publications

Water maser variability in a high-mass YSO outburst -- VERA and ALMA observations of S255 NIRS 3

Water maser variability in a high-mass YSO outburst -- VERA and ALMA observations of S255 NIRS 3

A multi-transition methanol maser study of the accretion burst source G358.93-0.03-MM1

The disk-outflow system around the rare young O-type protostar W42-MME

Contact Info

Product

Resources

About

¹³CH₃OH Masers Associated With a Transient Phenomenon in a High-mass Young Stellar Object