Super CO survey with NANTEN2
Hiroaki Yamamoto (Nagoya U.)
on behalf of “NASCO” projects
CMB workshop in Tokyo 2011/2/17
Contents
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CMB
Goal of study
Why are CO observations needed ?
Foreground sources of CMB obs.
NANTEN GPS ver.1 (NGPS)
Comparison of PLANCK results with NGPS
NASCO Projects
Research Group
• Y. Fukui
Leader ・ Global Analysis including NASCO
• T. Okuda
Development of NASCO receiver system, Observations
• T. T. Takeuchi Modeling of foreground radiation, Development of
component separation by statistical methods
• K. Ichiki
Theoretical study in terms of cosmology
• S. Inutsuka
Research for magnetic field and turbulence in ISM by MHD.
• H. Maesawa Support of receiver developments
• Collaborators （PLANCK members in IAS France)
– J.-L. Puget: PI of HFI in Planck
– F. Boulanger: PI of ERC Advanced Research Grants
– J.-P. Bernard: Partner of Boulanger
|Cosmic Microwave Background
WMAP; Subtracted map of foreground sources
Freq. (dF) [GHz]
23 (5.5),
33 (7.0),
41 (8.3),
61 (14.0),
94 (20.5)
Main Results
・ Age ~ 13.7 billion years
・ Composition : baryon ~ 4%, dark matter ~ 23%, dark energy ~ 73%
・ Corresponding to an inflation scenario with the results
・ Non detection of B mode polarization due to poor sensitivity
Goal of Study
Detection of B mode polarization in CMB
Giving Strong Constraint from observations to proposed inflation models.
B mode polarization is so weak that it has been never detected so far.
Some foreground sources are
 higher fractional polarization than
expected for the CMB signals
Problem is
 poor knowledge about the amplitude and
scale of the polarization of foreground emission
Planck can identify large angular
scale B mode amplitude.
Important thing is
 understanding nature of the foreground sources
Why are CO observations needed ?
In case of WMAP
Key component to subtract at microwave
・Synchrotron
Galactic center
・Free-free emission
LFI
HFI 12CO(J=1-0)
・Dust radiation
200MHz
CF 30 44 70 100 143 217 353 545 857
WMAP
Maximum
Frequency
104GHz
SF 27 :39.6
63 83.5
119.4 ~181.2
294.8 455.1 715.6
 Contribution of CO is not included
EF 33 48.4 77 116.5 166.5 252.8 411.2 634.9 998.4
PLANCK:
Gold et al. 2011, ApJS, 192,15
Component maps by Maximum Entropy
VLSR (km/s)
Method (MEM)
analysis
CO(J=1-0)  109,110,115 GHz
CO(J=2-1)  219,220,230 GHz
CO(J=3-2)  329,330,345 GHz
Strongest line emission in MCs.
Contaminated in observed bands.
One year all sky survey by Planck
Planck all-sky foreground maps
The Galactic Cold Core Population
Planck Early Results: The Galactic Cold Core Population Revealed by the First All-Sky Survey
Ade et al. (2011)
the density of cold cores in the Milky Way through its three highest frequency
channels.
Cold clumps vs CO clouds
Planck Early Results: The Galactic Cold Core Population Revealed by the First All-Sky Survey
Ade et al. (2011)
CO: Dame et al. (2001)
7.5’ – 30’ grid at HPBW of 8.8’
Resolution of CO survey by Dame et al. is not enough
to compare with Planck data. New CO data is …
NANTEN GPS ver.1 (NGPS)
NANTEN
12CO(J=1-0)
Integrated Intensity map
600 km s-1
HFI 100GHz vs NGPS
Planck results with NGPS
30GHz
353GHz
857GHz
Orion
Composite image of above 3 images
NANTEN 12CO (J=1-0)
Planck results with NGPS
Composite image of 557GHz, 857GHz
and IRAS 100 um
Ophiuchus to Aquila
NANTEN 12CO (J=1-0)
NAnten Super CO survey (NASCO)
• New Survey with OTF by NANTEN2
at Atacama (Alt. 4865m) in 12CO and
13CO(J=1-0) simultaneously.
• Survey beyond NGPS
• Covering 70% area of whole sky
Survey
Name
Coverage
(deg)
HPBW
(‘)
Grid
(‘)
Vel cov.
(km/s)
Vel reso.
(km/s)
RMS[K]@
1km/s reso.
Total points
(million)
NGPS
200<L<60,B<|10|
2.6
4-8
±300
1.0
~0.35
1.1
NASCO
70% of sky
2.6
1
±1300
0.16
~0.2
20
NAnten Super CO survey (NASCO)
Expected results
NASCO: Large Scale mapping in CO never done before
• Covering 70% of whole sky
• Enabling us comparative study with PLANCK
• Implementation of an estimation of CMB B mode component by
progressing the study of foreground sources
Breakthrough for ISM study etc.
• Comparative study with sub-mm, infrared (Herschel, AKARI) to
gamma-ray (Fermi etc.) in large scale
• Spreading effect as historical common property in Astronomy
NAnten Super CO survey (NASCO)
Current status
• Collaboration with Planck satellite
– 1991：start collaboration with IAS in France (Fukui)
– 2007：Launch WG7 group (Planck consortium) and conclude a
MoU with the WG7 group on the use of NGPS in order to
estimate foreground components.
– 2010：Proposal of NASCO
• Development of NASCO
test receiver
– 2010/4：Start to develop
– 2011/1：Installing in NANTEN2 and
checking system
NASCO test receiver system
NAnten Super CO survey (NASCO)
Schedule 2011-2015
○ Carrying out Super large scale mapping in CO (NASCO)
○ Total Analysis
Estimation of density and velocity structures in ISM using NASCO and HI dataset
Establish of 3D magnetic field model in the Milky Way from polarization from PLANCK
CMB dataset： Planck, BICEP, EBEX, SPIDER etc.
ISM dataset ：NASCO, PILOT, BLAST, EoR, CGPS, SGPS, GASS
• 2011：
– Observation by a test receiver, Development of NASCO receivers
– Comparative study / modeling of the ISM by using NGPS and PLANCK
• 2012-2015：
– Observations by NASCO receivers
– Establishing Higher accurate ISM model
– Estimation of CMB B mode polarization, constraint to inflation models
Summary
• PLANCK dataset includes CO components as
well as synchrotron, free-free emission and
dust radiation in microwave.
• It is important to remove the contribution of
CO gas and related foreground sources to
detect weak CMB B mode polarization
• NASCO Project is now on going to compare
the Planck data with MCs.