VERAVER
Aユーザーズミーティング2008
ユーザーズミーティング2008

プロジェクト観測結果報告
プロジェクト観測結果報告
近距離分子雲立体構造

Tomoya HIROTA (VERA, NAOJ)
1

Nearby SFRs project
Distance to SFRs within 1 kpc from the Sun
 One of the initial projects (since 2004 January) Aim of this project Distance measurements
 3-D structure of molecularclouds Refine the physics ofstar--formation
star

Distribution of molecular clouds(Grabelsky et al. 1988)

2

After the UM2006
Publications
 Orion KL (H2O maser; Hirota et al. 2007, PASJ, 59, 897)
 IRAS 1629316293-2422 (Imai et al. 2007, PASJ, 59, in press)
 NGC1333 (Hirota et al. 2008, PASJ, 60, in press)

 Orion KL (SiO maser; Kim et al. 2008, in preparation)3

After the UM2007


Publications
 Orion KL (H2O maser; Hirota et al. 2007, PASJ, 59, 897)
 IRAS 1629316293-2422 (Imai et al. 2007, PASJ, 59, 11071107))
 NGC1333 (Hirota et al. 2008, PASJ, 60, 37)37)

 Orion KL (SiO maser; Kim et al. 2008, PASJ, 60, in press)
press)
 L1204G (Hirota et al. 2008, PASJ, 60, in press)

4Distance to Orion Nebula

H2O maser in Orion KL (Hirota et al. 2007) 2.29+/2.29+/--0.10 mas = 437+/
437+/--19 pc



SiO maser in Orion KL (Kim et al. 2008)
 2.39+/2.39+/--0.06 mas = 419+/
419+/--6 pc

Radio cont. from WTTSs

1’ = 0.12pc

 389 +24/+24/-21 pc(GMR-A: Sandstrom et al. 2007)(GMR 414+/
414+/--7 pc(4 WTTSs: Menten et al. 2007)(NIR image of ONC; Menten et al. 2007)

Source I(masers)
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Distance to ρ-Oph

H2O maser in IRAS16293IRAS16293-2422 (Imai et al. 2007)
 5.6 +1.5/+1.5/-0.5 mas =178 +18/+18/-37 pc
 Maser spots > beam size; common for nearby YSOs

Radio cont. from WTTSs (Loinard et al. 2008)
 DoAr 21:

DoAr 21 and S1

121.9 +5.8/+5.8/-5.3 pc
 S1:
116.9 +7.2/+7.2/-6.4 pc(Spitzer image of ρ-oph cloud;Jorgensen et al. 2008)

IRAS16293
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Distance to NGC1333


H2O masers (Hirota et al. 2008)
 4.25+/4.25+/--0.32 mas =235+/=235+/--18 pc

 Photometric method:

220 pc (Cernis 1989)
 HIPPRACOS:
318+/--27 pc for Per OB2318+/(de Zeeuw et al. 1999)(SII and Ha image; Bally et al. 1996)

HH7-11

10’ = 0.7 pc

7Proper motion of NGC1333


VLA observations by CarrascoCarrasco-Gonzalez et al. (2008)
 Systematic proper motion~(9.3+/0.9, -10.6+/10.6+/-1.8) mas yr-1
 Consistent with the masers~(17.9, -7.9) mas yr-1
(10.6, -10.0) mas yr-1
0.03 pc
MasersVLA
sources8Distance to L1204G
Star-forming region in the Cepheus
StarCepheus--Cassiopeia region
 H2O masers in IRAS22198+6336 (Hirota et al. 2008)
 Highly variable (<1yr) Measured by using 26 spots

L1204G/
IRAS22198+6336

 1.309+/1.309+/--0.047 mas =764+/--27 pc
764+/(DSS 2nd RR-band imageof L1204/S140 region, 30’=6.6 pc
fov of 2deg. X 2deg.)

L1204A/S140IRS

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IRAS22198+6336 in L1204G
Previous studies
 Kinematic distance : 1.3 kpc
 1300 Lsolar : Massive YSO (e.g. SanchezSanchez-Monge et al. 2008)

Present results Pallaractic distance: 764+/
764+/--27 pc
 450 Lsolar : Consistent withintermediate-mass YSOintermediate(<7Msolar)
 No NIR counterpart --- Class 0/I
10IRAS22198+6336 in L1204G


VLA (Sanchez(Sanchez-Monge et al. 2008) and VERA results
 Intermediate
Intermediate--mass Class 0 source, with jets/disk system?
 To be confirmed by the VLAVLA-A config. observations(Hirota, in prep.)11

Next season

H2O masers in SFRs within 1 kpc from the Sun Orion (Orion A) Cepheus Perseus Taurus, Ophiuchus,Serpens, Monoceros,Cygnus …

Distribution of molecularclouds (Dame et al. 1987)

12Orion--Monoceros complex
Orion
South Filament(457pc)Northern Filament(393pc)

Crossbones(465pc)

Orion East(120pc)
Mon R2(800pc)

NGC2149(425pc)

5deg = 37 pc

Scissors(~150pc)
Orion B (387514pc)
Orion A(412-521pc)

Orion KL

Distribution of molecular clouds (Wilson et al. 2005)

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Perseus complex
IC348 B1
PerOB2

NGC1333
Taurus

IC348
B1

NGC1333
L1448

Distribution of molecular clouds (Ridge et al. 2006)
and their distances (Cernis 1993)

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Cepheus--Cassiopeia region
Cepheus

Distance ranging from 0.10.1-3 kpc

L1204
S140W3NGC281

Cep A

Close group (140-440pc)
Distant group (600-1000pc)

Distance to dark clouds (Cernis 1993)

Clouds in Perseus arm (2k-3kpc)

Distribution of molecular clouds and YSOs
(Yonekura et al. 1997, Grabelsky et al. 1988)

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SummaryDistances to Orion KL, NGC1333, IRAS 1629316293-2422,
and L1204G were reported

Annual parallax of Orion KL has been refined basedon the observations of the SiO masers

VERA data have come into use with VLA/VLBA
 to reveal 33-D structure of molecular clouds
 to reveal dynamical properties of YSOs

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