Variability of Water Masers in W49N: Results from the Effelsberg - - PowerPoint PPT Presentation

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Variability of Water Masers in W49N: Results from the Effelsberg - - PowerPoint PPT Presentation

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Variability of Water Masers in W49N: Results from the Effelsberg Long-term Monitoring Programme (2014-2017) Busaba Hutawarakorn Kramer MPIfR/NARIT Team & Collaborators Effelsberg Observations: MPIfR - Alex Kraus, Karl Menten Following up

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Variability of Water Masers in W49N:

Results from the Effelsberg Long-term Monitoring Programme (2014-2017)

Busaba Hutawarakorn Kramer

MPIfR/NARIT

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Team & Collaborators Effelsberg Observations: MPIfR - Alex Kraus, Karl Menten Following up KaVA Observations (2017): Hirota (NAOJ) and Asanok (NARIT)

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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Talk Outline

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Ø About W49N Ø Nearly Simultaneous Observations of the 2014 Major Outburst Ø Search for Periodic Flares during 2014-2017 Ø Effelsberg & KaVA Monitoring Observations Ø Discovery of the New Major Outburst in September 2017 & Following-up Observations with Torun Ø Summary

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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About W49N

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  • W49N is part of W49A - the most

luminous (> 107 L¤) and the most massive( ~ 106 M¤ ) GMC in our Galaxy (Sievers et al. 1991)

  • Distance = 11.1 +/- 0.8 kpc (parallax

measurement, Zhang et al 2013)

  • Well-studied since 1970
  • 99% of the total flux of W49N

contained around UCHII region G

  • Associated with H2O masers and
  • ther masers (e.g. OH and methanol)

De Pree et al 2000

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VLA Observations of Water masers and UCHII Regions (De Pree et al 2000) + positive vel. Δ negative vel.

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183 GHz May 2014 30m IRAM Granada, Spain (G. Xin, H. Wiesemeyer) 321, 325, 355, 439, 471, 475 GHz May 2014 12m APEX Chile (K. Menten, T. Kaminski) Started in Early 2014 - Major high velocity flare( Peak flux ~ 80,000 Jy @ ~ -97 km/s) reported by Tolmachev in The Astronomer’s Telegram on 28 January 2014 to have

  • ccurred since September 2013

Nearly Simultaneous Observations of the 2014 Major Outburst

From February 2014 22 GHz, 100-m Effelsberg (B. Kramer & A. Kraus)

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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Interferometric Observations

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321, 325 GHz SMA - May 7, 2014 (N. Patel, T. Kaminski) 22 GHz VLBA – May 8, 2014 (B. Zhang)

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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22 GHz – Observations with 100m Effelsberg

22 GHz, 28-Feb-14 100m-Effelsberg

Flux Density (Jy)

The extreme high velocity features up to VLSR up to -256 km/s and +271 km/s

  • First detected in 1975 (Morris 1976)
  • VLA observation (McGrath 2004) also detected them up to -352 km/s and +375 km/s

Using FFT spectrometer with 65,536 channels and a bandwidth of 100 MHz centered at the systemic velocity of our sources => the spectral resolution 0.02 km/s => smoothed to 0.08 km/s

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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  • First detection of 475 GHz line

in SFRs

  • Detection of both 321 and

325 GHz lines

  • Non detection at 354, 439,

471 GHz

  • Several features coincide, also

the high velocity flare features => line ratio study possible to constrain pumping models (Neufeld & Melnick 1991)

Submm Observations

APEX 12m + IRAM 30m

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VLBA Map of the 2014 Outburst

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Observed on May 8, 2014 (Kramer et al. in prep)

−300 −200 −100 100 200 300 LSR Velocity (km s−1) 5000 10000 15000 20000 25000 30000 35000 40000 Flux Density (Jy)

−1.0 −0.5 0.0 0.5 1.0 1.5 East offset (arcsec) −1.5 −1.0 −0.5 0.0 0.5 1.0 North offset (arcsec) −300 −240 −180 −120 −60 60 120 180 240 300 VLSR (km s−1)

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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VLBA Observations 2010-11

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BeSSeL Project ( Zhang et al. 2013 )

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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The location of 2014 Outburst @ -97 km/s

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−1.0 −0.5 0.0 0.5 1.0 1.5 2.0 East offset (arcsec) −1.5 −1.0 −0.5 0.0 0.5 1.0 1.5 North offset (arcsec) −100.0 −99.2 −98.4 −97.6 −96.8 −96.0 −95.2 −94.4 −93.6 VLSR (km s−1)

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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VLBA Map of the 2014 Outburst

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Observed on May 8, 2014 (Kramer et al, in prep.)

−1.0 −0.5 0.0 0.5 1.0 1.5 East offset (arcsec) −1.5 −1.0 −0.5 0.0 0.5 1.0 North offset (arcsec) −300 −240 −180 −120 −60 60 120 180 240 300 VLSR (km s−1) −0.6 −0.4 −0.2 0.0 0.2 East offset (arcsec) −0.4 −0.2 0.0 0.2 0.4 North offset (arcsec) −300 −240 −180 −120 −60 60 120 180 240 300 VLSR (km s−1)

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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VERA Observation of the outburst in 2003

Honma et al 2004 The 2003 outburst @ -30.7 km/s

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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SMA – submm H2O Masers

14 Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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SMA – submm H2O Masers

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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The peak of high velocity feature lies ~ 0.3” South, ~ 0.1” East

  • f the peak of the central

velocity feature

SMA – submm H2O Masers

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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Effelsberg Monitoring after the2014 Major Outburst

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Awarded observing time with Effelsberg – 26 runs, every 2 weeks, full sample, 1 year period (Aug 2016-July 2017) - Kramer B., Kraus, Menten

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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Search for Periodic Flares

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Periodic & alternating flare of water masers (@22GHz) and methanol masers (@6.7 GHz) (Szymczak et al 2016)

Figure 3. Light curves of 6.7 and 22 GHz maser features which coincide in velocity within less than 1.1 km s−1.

Figure 2. Selected spectra of 6.7 GHz methanol maser (red) and 22 GHz water maser (blue) of G107.298+5.639. Red and blue vertical bars show the methanol flux density and the water antenna temperature scales, respec-

  • tively. The methanol profile taken on MJD 57341 has a peak of 57.7 Jy at

−7.43 km s−1 not shown in the plot.

See Posters by Mateusz Olech and Michal Durjasz

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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The 2014 Major Outburst @-97 km/s

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  • Search for Periodic Flares
−1.0 −0.5 0.0 0.5 1.0 1.5 2.0 East offset (arcsec) −1.5 −1.0 −0.5 0.0 0.5 1.0 1.5 North offset (arcsec) −100.0 −99.2 −98.4 −97.6 −96.8 −96.0 −95.2 −94.4 −93.6 VLSR (km s−1)

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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  • −1.0
−0.5 0.0 0.5 1.0 1.5 2.0 East offset (arcsec) −1.5 −1.0 −0.5 0.0 0.5 1.0 1.5 North offset (arcsec) −20 −16 −12 −8 −4 4 8 12 16 20 VLSR (km s−1)
  • Search for Periodic Flares
−1.0 −0.5 0.0 0.5 1.0 1.5 2.0 East offset (arcsec) −1.5 −1.0 −0.5 0.0 0.5 1.0 1.5 North offset (arcsec) −72.5 −70.0 −67.5 −65.0 −62.5 −60.0 −57.5 −55.0 −52.5 −50.0 VLSR (km s−1)

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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Following up with KaVA, awarded time = 3 epochs with monthly separation ) – starting in 03/2017 (in collaboration with KaVA Team – Hirota and Asanok et al.)

Effelsberg & KaVA Monitoring Observations

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018 VLBA map (Kramer) KaVA map (Asanok, Hirota)

(Kramer et al.)

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Effelsberg & KaVA Monitoring Observations

22 Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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  • 300
  • 200
  • 100

100 200 300 10,000 Jy 2014-02-28 2014-03-27 2014-05-09 2014-08-21 2014-10-24 2015-05-02 2016-08-22 2016-10-10 2016-12-04 2017-01-02 2017-05-25 2017-06-05 2017-08-14 2017-09-07 Velocity (km/s)

07-Sep-2017 New Burst ~ 35,000 Jy

Discovery of the New maser Superburst in September 2017

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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[M2O] Maser Monitoring Organization

(Led by G. MacLeod & S. Goedhart in South Africa)

  • ,

Korea,

Credit:

  • Dr. Gordon MacLeod
  • Ø Launch: 2017/09/07 @IAU Symposium 336

Ø Aim

  • Collaboration through single-dish monitor for the maser variability
  • Achievable amazing monitor: 24 hrs continuous, high-frequent, etc. –

Follow-up interferometer/VLBI obs. by flare-alert from collaborators

Ø Participants

Australia, Canada, China, France, Germany, Italy, Japan, Korea, Latvia, Poland, Russia, South Africa, Thailand (future), Ukraine, USA

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

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Effelsberg & Torun Collaboration in Maser Monitoring Observations

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See Poster by Pawel Wolak

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018

VLBI Following up – Burns (PI- EVN), Orosz (PI-VLBA), and Hirota (PI-KaVA)

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Summary

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Ø High resolution wide band spectroscopy at Effelsberg allow us to study the extremely high velocity masers which are associated with jet/shock front Ø Simultaneous multi-frequency observations will not only allow us to study the physics of the regions but also the physics of maser process itself. Ø Following up interferometric observations (e.g. KaVA, VLBA, SMA, ALMA) would be crucial to confirm locations of the flare/outburst regions à study the flare region in details Ø Time domain astronomy provides additional valuable information [à New Discoveries!!!] though difficult to organize but collaborations help. Thanks to the new global monitoring campaign (M2O)- Maser Monitoring Organization

Effelsbeg Science Workshop 2018, Bonn, 20.02.2018