IGRINS Observations of Extended IFOs in the UWIFE Survey 2017. 07. - - PowerPoint PPT Presentation

IGRINS Observations of Extended IFOs in the UWIFE Survey

• 2017. 07. 28

Seoul National University Yesol Kim Supervisor : Bon - Chul Koo (SNU) Collaborators : Tae - Soo Pyo (NAOJ), Yong - Hyun Lee (SNU), Jae - Joon Lee (KASI), Dirk Froebrich (Univ. of Kent), Heeyoung Oh (SNU)

IGRINS Workshop 2017

Contents

• Introduction - the UWIFE survey
• Previous [Fe II] studies
• Spectroscopic follow-up of UWIFE sources with IGRINS
• 1. G25.8+0.2

(1) Detected lines (2) Position – velocity diagram of [Fe II] and Br-gamma

• 2. HH 803

(1) Position – velocity diagram

• Future Work – other sources to observe

UWIFE survey

■ UKIRT Wide - field Infrared Survey for Fe+ (Lee+2014)

Unbiased imaging survey using narrow - band filter with central wavelength of 1.644 μm, covers the 1st

st Gal

alactic c qu quadrant (7° < l < 62°, b ≤ |1°.5|).

• Observations were conducted by WFCAM at UKIRT (2012.5 ~ 2013.8)
• pixel size: 0.2”, median seeing: 0.83”
• 5σ detection limit : 18.7 mag, surface brightness limit : 8.1 × 10-20 W m-2

→ UWIFE is first high - resolution, deep [Fe II] survey for 1st Galactic quadrant.

Suitable for systematic [Fe II] study of shocked, dense & unseen material in obscured region!

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Figure 1. Observation coverage of UWIFE survey l =7 ° l= 62 °

Motivation

What about other, unseen [Fe II] - emitting sources? We are compiling a comprehensive catalogue

 IFO : Ionized Fe Object

Figure 2. Observation coverage of UWIFE with known sources

UWIFE extended IFO catalog

• Manual search & automatic search by source detection algorithm.

(Developer : Dirk Froebrich)

• In total, we identified 202 sources (1.23 source in 1 deg2).

■ Extended Ionic Fe Object (IFO) catalog (Kim et al. in prep)  Basic physical properties (coordinate, size, flux, distance, etc) are enlisted, as well as counterpart of IFOs. About half of IFOs are associated with YSOs.  Most of IFOs in this study are newly discovered [Fe II] objects.

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Table 1. (left) Catalog of extended IFOs. (right) Number of IFOs classified with counterpart.

UWIFE extended IFO catalog

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 Spatial distribution of IFOs related to early evolutionary phase is clustered, highlighting star - forming regions (e.g. M 16, M 17 in l ~ 16°).  Gaussian-fitted center position of IFO latitude distribution is -0.22° (FWHM ~1.5°), consistent with distribution of Galactic arm (Goodman+2014).

Figure 3. Spatial distribution of IFOs in catalog Figure 4. Spatial distribution of IFOs

• n artist’s impression of Milky way.

Follow-up observations of IFOs

• We are conducting spectroscopic follow-up of UWIFE sources

with IGRINS.

• 1. G25.8+0.2
• On-off mode, as a part of mini - queue (2015.08.05)
• Exposure time : 340s × 2
• Two slit positions were placed on [Fe II] shell.
• 2. HH 803
• On-off mode, observed on 2016.10.11. (PI : Heeyoung Oh)
• Exposure time : 300s × 2
• Two slit positions where [Fe II] & H2 are bright.

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Follow-up study 1 : G25.8+0.2

■ IFO J183740.829-061452.41

• A shell-like IFO located near

HII region G25.8+0.2.

• [Fe II] flux ~ 2.49 x 10-16 W/m2

: Falls in one of the faint SNR in [Fe II] (Lee, in prep).

• Radio recombination line was
• bserved with distance of 6.5±0.3kpc

(Russeil+2003). : Size of IFO is ~6’, 11 pc

[Fe II]-H

Red : Slit position

Figure 5. IFO J183740.829-061452.41 on UWIFE continuum - subtracted [Fe II] data.

G ~ 26° region

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Follow-up observations of IFOs

• X-ray PWN / SNR candidate and young pulsar AX J1837.6-0610

seem to be associated with [Fe II] shell (Sakamoto+2001, Lin+2008).

Red contour : 0.7-2keV Green contour : 4-10keV Blue * : AX J1837.6-0610 Magenta * : IRAS 18348-0616

GLIMPSE 8um New-GPS 20cm UWIFE [Fe II] - H SHS H-α

Figure 6. Multiwavelength view of G~ 26º region.

G25.8+0.2

• [Fe II] 1.64um, He I 2.05um, Br-γ, Br 10, Br 11, Br 12, Br 14 were detected.
• [Fe II] structure is distinct from Hydrogen & Helium structures.

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Follow-up observations of IFOs

• Slit position 2 : parallel to [Fe II] shell
• Slit position 1 : perpendicular to [Fe II] shell

[Fe II] He I Br-γ Br 10 Br 11 Br 12 Br 14

Figure 7. 2D spectrum of detected lines

G25.8+0.2

• [Fe II] is spatially distinct from Br-γ, enhanced where UWIFE [Fe II] shell exists.
• A shocked region was revealed, with [Fe II] / Br-γ ratio up to 2.

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Follow-up observations of IFOs * Slit position 1 * Slit position 2

Figure 8. 2D spectrum of [Fe II] and Br- γ

Follow-up study 2 : HH 803

Figure 9. IPHAS Hα image

• f HH 803 region

2D spectrum of detected lines

1.74 1.78 1.68 2.45 2.43 2.41 2.25 2.22 2.12 2.07 2.03 2.42

P9 P10

• Twelve molecular hydrogen

lines were detected.

• All show knots revealed in

UWISH2 image (figure 10).

Figure 11. 2D spectrum of detected Hydrogen lines Figure 10. H2 and [Fe II] image with IGRINS slit positions

Follow-up study 2 : HH 803

■ 2D spectrum of [Fe II] shows high velocity component, which is apart from low velocity molecular hydrogen structures.

Figure 12. H2 image of HH 803. Figure 13. 2D [Fe II] & H2 spectrum of HH 803

Candidates to observe

• Variety of [Fe II] morphology from YSOs

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Future Work

Figure 14. Continuum-subtracted [Fe II] image of YSO–related IFOs. Red + ,x: H2

YSO? PN?

Candidates to observe (in Eagle Nebula)

[FeII]-H

Hα

K [Fe II] J

Figure 15. Hα image of Eagle with zoomed-in JHK three-color images.

Candidates to observe

• IFO J190816.78+052506.1
• Clumpy amorphous structure in [Fe II].
• An Hα counterpart was discovered and

suspected to be a PN, spectroscopic follow-up could not find any PN emission line (Viironen et al. 2009, Sabin et al. 2014).

• Exploiting UWIFE and UWISH2 data,

we found that this IFO may associate with chains of multiple [Fe II] and H2

• knots. These aligned diffuse structures

are located inside an IRDC DOBASHI 1675 (Av = 8.22).

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Future Work

35.0 30.0 25.0 19:08:20.0 15.0 10.0 29:00.0 28:00.0 27:00.0 5:26:00.0 25:00.0 24:00.0 23:00.0 I F O J 1 9 8 1 6 . 7 8 + 5 2 5 6 . 1

N E

Figure 17. Wide view around the source in H2. Black ellipse : H2 knots. White circle : IFO. Figure 16. [Fe II] and GPS H-band image of the IFO.

Candidates to observe

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Future Work

Figure 19. [Fe II] and GPS H-band image of IFO J192348.169 +143641.5 and IFO J192354.032 +143558.0. Figure 18. [Fe II] and GPS H-band image of IFO J181845.167 -150257.2

• IFO J181845.167 -150257.2
• Located inside the SNR G015.9+00.2.
• No other possible counterpart was found.
• The nearest object is CXOU J181852.0-

150213, an x-ray source which suspected to be related to SNR.

• IFO J192348 & J192354
• J192348 is a broken shell surrounding

candidate LBV [OMN2000] LS1 (Source 1 in H-band image).

• The central source of this IFO is O4 I P-

cygni supergiant with initial mass of 120 solar mass, one of the massive and evolved star in Milky way (Clark et al. 2009).

• YSO (Source 2 in H-band image) is located

in the central position of J192354.

Summary

• We designated [Fe II] 1.644um – emitting sources as IFOs and

identified in the UWIFE survey area in unbiased way.

• About 202 extended IFOs are identified, often associated with H2.
• We conducted spectroscopic follow-up with IGRINS, two sources

(SNR candidate G25.8+0.2 & HH 803) were observed so far.

• IGRINS successfully carried out follow-up, revealed shock-excited

[Fe II] structure in SNR candidate.

• IGRINS will be useful for studying newly found [Fe II] & H2

sources in the UWIFE & UWISH2 survey.

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Complementary search by computer

 Source detection algorithm (Developer : Dirk Froebrich)

• Median filter to remove remaining stars
• Subtract large scale backgrounds
• Draw contours above 1σ noise level

 Preliminary Results

• Results in tens of thousands of contours
• About 5% would be real  Remove false detection (manually)
• Both method found 189 + 103 only manually + 20 only automatically+ α

Automatic Manual Automatic Manual Artifacts