NRO Legacy Project CO Galactic Plane Survey. Tomofumi Umemoto (NRO) et al.

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1 NRO Legacy Project CO Galactic Plane Survey Tomofumi Umemoto (NRO) et al.

2 Members Kagoshima univ. Handa, T., Nakanishi, H., Omodaka, T., Matsuo, M., Oszawa, T. Osaka prefecture univ. Onishi, T., Nishimura, A., Tokuda, K. Joetsu education univ. Tosaki, T., Odaka, D. Meisei univ. Onodera, S., Sofue, Y., Tsuda, Y. Nagoya univ Torii, K., Nakashima, T. ISAS Tsuboi, M. Univ. of Tokyo Ohashi, S. NRO Umemoto, T., Kuno, N., Minamidani, T., Hirota, A., Morokuma(Matsui), K. Chile observatory Mizuno, N., Shinnaga, H., Higuchi, A., Mizusawa VLBI observatory Honma, M. et al.

Introduction What$determine$the$form CO+HI Study of galaxies Formation of molecular clouds -

and internal structures of interstellar gas along with their evolution(formation of dense gas) Study of

Orion(Ikeda+2007) Clump(~a few pc, ~10 3 Mo) surveys Toksaki+2011 - cluster/massive star

3 Introduction What$determine$the$form CO+HI Study of galaxies Formation of molecular clouds - M33(Tosaki+2011), Evolution of molecular clouds - IC342(Hirota+2011),M33(Onodera+2012) evolutionary process and internal structures of interstellar gas along with their evolution(formation of dense gas) Study of star formation in the Galaxy Core surveys in nearby moleclar clouds(<2kpc) - Taurus(Onishi+1996), Orion(Ikeda+2007) Clump(~a few pc, ~10 3 Mo) surveys Toksaki cluster/massive star formation(ridge+2003, Higuchi+2009) relation between GMC properties/evolutionary stage and properties of core/clumps Onodera$et$al.$2012 Ikeda$et$al.$2007

4 Next Generation Study ALMA era - direct imaging of GMCs in nearby galaxies Evolutionary process of ISM studies in GMC scale +Formation process of dense clumps studied in nearby GMCs - Observations of evolution of molecular clouds toward dense clumps is possible only in the Galaxy - Large area mapping of the Galaxy to investigate the properties of molecular gas in various environments (spiral arm, bar, active/inactive star forming regions) - Large area mapping of the Galaxy by dense gas tracer to find clumps before star formation Multi-line survey of the Galactic plane with high angular resolution

5 2. Galactic Plane Survey with the NRO 45m telescope

6 NRO Galactic Plane Survey OTF mapping of the Galactic plane and the outer disk in 12 CO(1-0), 13 CO,(1-0), C 18 O(1-0), simultaneously Mapping area l: 10 ~ 50 b: ±1 (80 deg 2 ) - Spiral arms (Perseus, Sagittarius, Scutum-Centaurus arms), bar structure, molecular gas ring l: 198 ~236 b: ±1 - Comparison between inner and outer regions (GemOB1, MonOB1, Maddalena cloud, CMa OB1 etc) - Closer than the inner region => Noise level ~ 3 times higher than the inner region => Observing time: ~1/9

7 NASA/R.$Hurt$$

8 Observation Plan Receiver : FOREST (Tsys =150K@ 13 CO, 300K@ 12 CO) Spectrometer : SAM45(velocity resolution : 1.3 km/s) Grid spacing : 15 Sensitivity - Trms(Ta*) 13 CO dv= 1.3 km/s ~200 (cf. Ikeda & Kitamura 2009, ApJ 705, L95) - Trms(Ta*) = 12 CO dv= 5km/s (~0.2K dv= 1.3km/s) Average density in the Milky Way-2SB survey: 10-2 Mo pc -3 Observation time - 1 x1 OTF mapping : 7.5 hr hr/yr x 1deg 2 /7.5 hr x 0.6 (weather factor) =32 deg 2 Total observation time: 400hr x3yr (~96 deg 2 )

9 Previous Surveys Galactic Ring Survey (Jackson+ 2006) - 13 CO(1-0), Beam size: clouds, 6124 clumps (Rathborne+2009)

ThrUMMS: large-scale maps of the molecular Milky Way Peter Barnes1, Erik Muller2, Balthasar Indermühle3, Stefan O Dougherty1,4, Vicki Lowe3,5, Maria Cunningham5, Gary Fuller6, Audra Hernandez1,7,

edu 2 National Astronomy Observatory of Japan 3 CSIRO Astronomy & Space Science 4 University of Arizona 5 University of New South Wales 6 University of Manchester 7 University of Wisconsin On Going

distribution in our Galaxy, the Columbia-CfA CO survey (Dame et al 2001) is one of the most highly-cited studies in astronomy.

(Molinari et al 2010). Moreover, these continuum surveys also lack the kinematic dimension, necessary for a full three-dimensional understanding of the Milky Way s structure and dynamics.

In addition, modern receiver technology can now map multiple molecular species simultaneously.

10 ThrUMMS: large-scale maps of the molecular Milky Way Peter Barnes1, Erik Muller2, Balthasar Indermühle3, Stefan O Dougherty1,4, Vicki Lowe3,5, Maria Cunningham5, Gary Fuller6, Audra Hernandez1,7, Jonathan Tan1 1 University of Florida; peterb@astro.ufl.edu 2 National Astronomy Observatory of Japan 3 CSIRO Astronomy & Space Science 4 University of Arizona 5 University of New South Wales 6 University of Manchester 7 University of Wisconsin On Going Surveys The Three-mm Ultimate Mopra Milky way Survey Progress to Date Starting point: As a testament to the importance of a homogenous and wide-field understanding of the large-scale molecular cloud distribution in our Galaxy, the Columbia-CfA CO survey (Dame et al 2001) is one of the most highly-cited studies in astronomy. Yet its angular resolution of just 8 limits critical new comparisons with recent broad-spectrum Milky Way surveys, such as GLIMPSE (Benjamin et al 2003), the BGPS (Aguirre et al 2011), and Hi-GAL (Molinari et al 2010). Moreover, these continuum surveys also lack the kinematic dimension, necessary for a full three-dimensional understanding of the Milky Way s structure and dynamics. While the GRS (Jackson et al 2006) mapped 13CO in part of the first quadrant, at this higher (~1 ) resolution, the southern Milky Way is largely unexplored. In addition, modern receiver technology can now map multiple molecular species simultaneously. Therefore, a significant update to wide-field maps of the Milky Way is now both feasible and urgently needed. Galactic plane survey (Moore et al.) - With the 22m Mopra dish (part of ATNF), we have developed a very fast OTF mapping technique (which could be practically extensible to many existing facilities; Barnes & Dame 2009), and have used this to perform a complete, high-resolution (1. 2 and 0.1 km/s) mapping survey of a 58 1 area in the Milky Way s fourth quadrant, simultaneously in four J=1 0 lines (12CO, 13CO, C18O, and CN). JCMT Legacy suvey l: b:±0.5, is planning to map the same region with our survey Fourth quadrant WCO map from Dame et al. (2001). The red box shows the location of the ThrUMMS survey region to date. 12CO(3-2), 13CO(3-2), C18O(3-2); Beam size: ~14 ThrUMMS (Barnes, Muller et al.) - The Three-mm Ultimate Mopra Molky way Survey Expanded view of the above WCO map (integrated over all VLSR). l: b:±1 12CO(1-0), 13CO(1-0), C18O(1-0), CN ; Beam size: ~72 Sample ThrUMMS maps below VLSR ~ 55 to 40 km/s 12CO(1-0) Wow! Wow! (see also Symp.292 posters 403 and 409 for more on the G333 complex) VLSR ~ 75 to 55 km/s Wow! Sample 1: Here we show a section of the 12CO data cube from observations, comprising ~20% of our spatial coverage to date. The top panel is an expanded view of the Dame et al (2001) WCO map Barnes+ 2012

Advantage of NRO Survey High angular resolution 3

main Galactic structures Spitzer bubbles(<1 ):

simultaneously Structure of molecular clouds -

without SF Collaboration with VERA Measurement of

11 Advantage of NRO Survey High angular resolution 3 times higher than the GRS - resolve clumps in the main Galactic structures Spitzer bubbles(<1 ): massive SF regions Multi-line observation, simultaneously Structure of molecular clouds - Diffuse gas => dense gas NROGPS GRS Dens clumps without SF Collaboration with VERA Measurement of the distance - Relation with the Galactic structure 12 CO 13 CO C 18 O

Transition from HI to H2 Transition from atomic gas to molecular gas Requirement for molecular clouds formation - Comparison between the inner and outer Galactic disk percentage of molecular gas

12 Transition from HI to H2 Transition from atomic gas to molecular gas Requirement for molecular clouds formation - Comparison between the inner and outer Galactic disk percentage of molecular gas component How far do GMC exist in the Galaxy? - Star formation in low metallicity gas Matsuo+2013, in preparation - Radial variation of ICO-N(H2) conversion factor precise X CO Comparison with H1 - Large mapping area $ /23 - High angular resolution to resolve clump structures of molecular gas Spatially high dynamic range

13 PDF of Gas Density PDF of gas density and the Galactic structures Probability Distribution Function of gas density in the Galaxy - Log-normal distribution from AMANOGAWA-2SB survey(handa+2012) - Relation between PDF of gas density and the Galactic structures Distance from GC, arm vs. interarm, Bar vs. disk - Effect of angular resolution Can higher angular resolution change PDF? Is the log-normal kept in the scale smaller than GMCs?

Survey of Dense Clumps Survey of dense clumps in

GMCs - where are dense clumps within GMCs, number

mass, size, density, velocity dispersion etc.

relation with IMF of stars - difference between clumps

environments - Relation with Galactic structures (arm,

14 Survey of Dense Clumps Survey of dense clumps in various environments Distribution of dense clumps in GMCs - where are dense clumps within GMCs, number density of clumps Physical properties of clumps - mass, size, density, velocity dispersion etc. - clump mass function: Universal? relation with IMF of stars - difference between clumps w/wo stars and masers - clumps before cluster/massive star formation? Variation of physical properties in clumps in various environments - Relation with Galactic structures (arm, bar)? - Different hierarchical structures (5 kpc ring, outer galaxy)? Pilot survey for Star Formation Legacy Project SFE< 10% Higuchi+ 2010

15 4. Pilot Observation magenta: planned, red: observed (1 x1, time~2h16m)

16 Outer Galaxy by FOREST color scale: 0-10 K km/s

17 0.0 Inner Galaxy 13 CO J=1-0 by FOREST 10.0 km/s 20.0 km/s 30.0 km/s 40.0 km/s -0.5 Galactic latitude km/s 60.0 km/s 70.0 km/s 80.0 km/s 90.0 km/s km/s km/s km/s カラースケールは K km/s Galactic longitude

18 NROGPS vs GRS 0.0 Angular resolution NROGPS 13 CO J= to 65 km/s 0.0 Angular resolution GRS 13 CO J= to 65 km/s Galactic latitude Galactic longitude Galactic longitude

19 Plan of Next season large area mapping of some selected regions order to l-b or priorities M17 SWex: before massive SF from steep IMF Povich & Whitney (2010). multi-line observation SAM45 covered only three CO lines Development of new spectrometer ROACH If possible, adding molecular line, e.g., CS(2-1)

NRO Legacy Project: CO Galac4c Plane Survey. Nario Kuno (NRO) et al.

NRO Legacy Project: CO Galac4c Plane Survey Nario Kuno (NRO) et al. Members Kagoshima univ. Handa, T., Nakanishi, H., Omodaka, T., Tanaka, A.(M2), Matsuo, T.(M2) Osaka prefecture univ. Onishi, T., (graduate