ALMA Early Science ” Cycle1” Capability,
Policy & Science Case
Kazuya Saigo, Eiji Akiyama, Yasutaka Kurono, Yuichi Matsuda
(NAOJ Chile Observatory)
This Talk
• ALMA Overview
• ALMA Early Science Cycle 1 Capability I
Basic (Frequency/Sensitivity/Resolution)
• ALMA Early Science Cycle 1 Capability II
Observational Modes/Limit
• ACA
• ALMA Science
M100 (CSV result 12m array + ACA)
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
1
What is ALMA Project.
ＡＬＭＡ Project Overview
Atacama Large Millimeter/submillimeter Array
at 5000 m high site in northern Chile
• ALMA is in construction phase now.
Early Science Phase (Construction phase)
2011 Cycle 0 operation
2012 Cycle 1 operation … we are here!
2013 Cycle 2 operation
Inauguration (The end of a construction phase)
Full Operation Phase (All observation modes become available.)
- Main Array: 12m x 50 Antennas
- Atacama Compact Array: 12m x 4 + 7m x 12
BBC (C) 2012
• Even in cycle1 phase , ALMA achieves with the highest sensitivity and
the highest spatial resolution in observation at submillimeter wavelength.
• The ALMA Project is a joint project among East Asia, Europe, and North America
in cooperation with Chile.
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
2
Cycle 1 timeline
ALMA Early Science Cycle 1 Timeline
Timeline
-
31 May, 2012 (15:00UT) Call for Proposal
Opening of the Archive for proposal submission
← we are here!
12 July 2012 (15:00 UT) Proposal submission deadline
November 2012
Announcement of the outcome of the
Proposal Review Process
-
1 January 2013
Start of ALMA Cycle 1 Science Observations
-
（May 2013 Expected deadline for proposal submission for Cycle 2 )
-
31 October 2013
End of ALMA Cycle 1
Total observation time in Cycle1
2012/6
800 hours for 12m main array
Up to 800 hours for ACA system (see later)
About 200 highest priority projects are expected to be prepared for
scheduling.
Town Meeting Cycle1 Capability, Policy, & Scince Case
3
Cycle 1 Basic Capability
Cycle 1 Basic Capability
– Spectral Setting 1. Band (Frontend Detector)
example line
- Band 3 (2SB: 84GHz - 116GHz) : CO(1-0), HCO+(1-0), CS(2-1),
N2H+(1-0),,,
- Band 6 (2SB: 211GHz - 275GHz) : CO(2-1), HCO+(3-2), CS(5-4),
N2D+(3-2),,,,
- Band 7 (2SB: 275GHz - 373GHz) : CO(3-2), HCO+(4-3), CS(6-5/7-6), N2H+(3-2), N2D+(4-3),
- Band 9 (DSB: 602GHz - 720GHz): CO(6-5), HCO+(7-6/8-7), CS(13-12/14-13), H2D+(8-7/9-8), H2S,
2. Frequency Resolution & Setting (Correlator)
- We can select spectral setting from 15 spectral modes for each line.
Effective Channel Number: 3840 (x 2 pol.) for each spectral line
Frequency resolution:
30.5kHz～976.5kHz (⇔ Bandwidth=58.6MHz～2GHz)
Correlator Modes, dual-polarization (Proposers Guide A5)
Bandwidth
(MHz)
Channel spacing
(MHz)
Spectral Resolution
(MHz)
↓ dv at 100GHz
2000
15.6
31.2
1875
0.488
938
0.244
469
0.122
234
0.061
117
0.0305
58.6
2012/6
0.0153
(93.7km/s)
Velocity Resolution at 345GHz
Number of
channels
128
27km/s
0.976 (2.93km/s)
3840
0.85km/s
0.488 (1.46km/s)
3840
0.42km/s
0.244 (0.732km/s) 0.21km/s
3840
0.122 (0.366km/s) 0.11km/s
3840
0.061 (0.183km/s) 0.053km/s 3840
Town Meeting
Cycle1
Capability, Policy,
& Scince Case
0.0305
(0.091km/s)
3840
0.027km/s
Correlator
mode
TDM
FDM
FDM
FDM
FDM
FDM
FDM
4
Cycle 1 Basic Capability
Cycle 1 Basic Capability
– Spectral Setting 1. Band (Frontend Detector)
example line
- Band 3 (2SB: 84GHz - 116GHz) : CO(1-0), HCO+(1-0), CS(2-1),
N2H+(1-0),,,
- Band 6 (2SB: 211GHz - 275GHz) : CO(2-1), HCO+(3-2), CS(5-4),
N2D+(3-2),,,,
- Band 7 (2SB: 275GHz - 373GHz) : CO(3-2), HCO+(4-3), CS(6-5/7-6), N2H+(3-2), N2D+(4-3),
- Band 9 (DSB: 602GHz - 720GHz): CO(6-5), HCO+(7-6/8-7), CS(13-12/14-13), H2D+(8-7/9-8), H2S,
2. Frequency Resolution & Setting (Correlator)
- We can select spectral setting from 15 spectral modes for each line.
Effective Channel Number: 3840 (x 2 pol.) for each spectral line
Frequency resolution:
30.5kHz～976.5kHz (⇔ Bandwidth=58.6MHz～2GHz)
- ALMA can observe 4 spectral lines with different frequency resolution simultaneously.
Band 7 example1 Frequency Band which can be observed simultaneously
• CO (3-2) n = 345.8GHz
BW=938MHz (dv=0.42km/s)
Band 7
Lower Sideband
Upper Sideband • H13CO+(4-3) n = 347.0GHz
BW=469MHz (dv=0.21km/s)
• HCO+(4-3) n = 356.7GHz
BW=469MHz (dv=0.21km/s)
2012/6
• Continuum n= 358GHz
BW = 2000MHz
Town Meeting Cycle1 Capability, Policy, & Scince Case
5
Cycle 1 Basic Capability
Cycle 1 Basic Capability
– Spectral Setting 1. Band (Frontend Detector)
example line
- Band 3 (2SB: 84GHz - 116GHz) : CO(1-0), HCO+(1-0), CS(2-1),
N2H+(1-0),,,
- Band 6 (2SB: 211GHz - 275GHz) : CO(2-1), HCO+(3-2), CS(5-4),
N2D+(3-2),,,,
- Band 7 (2SB: 275GHz - 373GHz) : CO(3-2), HCO+(4-3), CS(6-5/7-6), N2H+(3-2), N2D+(4-3),
- Band 9 (DSB: 602GHz - 720GHz): CO(6-5), HCO+(7-6/8-7), CS(13-12/14-13), H2D+(8-7/9-8), H2S,
2. Frequency Resolution & Setting (Correlator)
- We can select spectral setting from 15 spectral modes for each line.
Effective Channel Number: 3840 (x 2 pol.) for each spectral line
Frequency resolution:
30.5kHz～976.5kHz (⇔ Bandwidth=58.6MHz～2GHz)
- ALMA can observe 4 spectral lines with different frequency resolution simultaneously.
Band 7 example2
Continuum emission only
(single continuum mode)
Band
7 7
Band
Lower Sideband
Upper Sideband
Bandwidth=8GHz (2GHz x4)
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
6
Cycle 1 Basic Capability
Cycle 1 Basic Capability
– Sensitivity & Resolution 1. Band (Frontend Detector)
example line
- Band 3 (2SB: 84GHz - 116GHz) : CO(1-0), HCO+(1-0), CS(2-1),
N2H+(1-0),,,
- Band 6 (2SB: 211GHz - 275GHz) : CO(2-1), HCO+(3-2), CS(5-4),
N2D+(3-2),,,,
- Band 7 (2SB: 275GHz - 373GHz) : CO(3-2), HCO+(4-3), CS(6-5/7-6), N2H+(3-2), N2D+(4-3),
- Band 9 (DSB: 602GHz - 720GHz): CO(6-5), HCO+(7-6/8-7), CS(13-12/14-13), H2D+(8-7/9-8), H2S,
2. Frequency Resolution & Setting (Correlator)
- We can select spectral setting from 15 spectral modes for each line.
Effective Channel Number: 3840 (x 2 pol.) for each spectral line
Frequency resolution:
30.5kHz～976.5kHz (⇔ Bandwidth=58.6MHz～2GHz)
- ALMA can observe 4 spectral lines with different frequency resolution simultaneously.
3. Sensitivity (Number of Antennas)
Sensitivity in Cycle1 = x 2 of Cycle0
Main Array:
32 x 12m antennas
Image quality improves!
Additional subarray: 7 x 7m anntenas + 2 x 12m single dish (ACA system) New!
4. Spatial Resolution (Configurations)
6 configurations
Maximum baseline = 166m ～ 1 km
2012/6
The maximum spatial resolution becomes 2.5
times higher than that in cycle 0.
Town Meeting Cycle1 Capability, Policy, & Scince Case
7
干渉計観測
参考
干渉計は普通の観測と違い、天体からのフラックス強度分布の
フーリエ分解成分を観測し、それを逆フーリエで画像に戻します※。
天球
天球上の位置ベクトル r
※天体からの電磁波を相関機で干渉させると、ビジビリティー（visibility,
干渉縞の明暗強度)が得られます。簡単のために１次元uで考えると、
n (u )  a1a*2 
Source
In (r ) exp( 2iur )dr
最大
18km
相関機
となります(実際は２次元)。逆フーリエ変換し天体輝度分布 I(r) を得ます。
Point 1: アンテナ間距離（基線）が長いアンテナペアで観測すると空間周波数が高い
（小さな空間スケールのフーリエ成分）情報が得られます(最大基線長⇔空間分解能)。
 250m 
Spatial Resolution: 0.72"  345GHz  n: 観測周波数、Lmax:最大基線長



n
  Lmax 
Point 2: 最短基線長間の相関からはもっとも低い空間周波数情報が得られます。より低
い空間周波数情報は得られないため、より広がった空間構造成分は干渉計観測画像か
ら落とされます(最短基線長⇔Resolve Out)。flux強度絶対値の不定性となります。
 345GHz   18m 
Resolve Outスケール：
n:観測周波数、Lmin:(実効)最短基線長
10.0" 
　


n
  Lmin 
Point 3: 単一鏡電波観測と異なり、干渉計観測では１つの座標の観測でも画像が得られ
ます。画像サイズはアンテナ口径で決まり各アンテナの視野(=Beam Size)と同じです。
視野サイズ（画像サイズ）： 14.9"  345GHz   12m 
n:観測周波数、Dantenna:アンテナ口径
2012/6
 n
  Dantenna 
Town Meeting Cycle1 Capability, Policy, & Scince Case
8
Cycle 1 Basic Capability
Cycle 1 Basic Capability
Sensitivity Examples1 (Continuum emission)
BW=8GHz, t = 60 min
1s sensitivity
Point Source Most Compact Conf.
Band 3 (100GHz) :
13 mJ
0.12mK (3.7”)
Band 6 (230GHz) :
17 mJ
0.15mK (1.6”)
Band 7 (345GHz) :
29 mJ
0.25mK (1.1”)
Band 9 (675GHz) : 220 mJ
2.0mK (0.55”)
2012/6
Most Extended Conf.
5.1mK (0.57”)
6.2mK (0.25”)
12mK (0.16”)
92mK (0.08”)
Town Meeting Cycle1 Capability, Policy, & Scince Case
9
Cycle 1 Basic Capability
Cycle 1 Basic Capability
Sensitivity Examples2 (Line emission)
・ALMA Science Verification Data (TW Hya)
integrated intensity,
intensity weighted
velocity field,
TW Hya is neayby protoplanetary disk
(d=50pc).
This is HCO+(4-3) maps from TW Hya,
with white continuum contours at 3 and
100 sigma.
・Sensitivity and Spatial Resolution in Cycle1
In Cycl1, ALMA enable us to obtain the
emission line image map of nearby
protoplanetary disks with the spatial
resolution of a 0.1" order.
Most Compact, dn=0.244MHz, t = 60 min
Most Extended, dn=0.244MHz, t = 60 min
Beam Size 1s
Beam Size 1s
Band 3 (100GHz) : 3.7”,
22 mK
Band 3 (100GHz) : 0.57”,
0.92 K
Band 6 (230GHz) : 2.6”,
28 mK
Band 6 (230GHz) : 0.25”,
1.13 K
Band 7 (345GHz) : 1.1”,
45 mK
Band 7 (345GHz) : 0.16”,
2.11 K
Meeting
Policy,
& Scince: Case
Band 9 (675GHz) : 0.55”,Town
353
mK Cycle1 Capability,
Band 9
(675GHz)
0.08”, 16.7 K
2012/6
10
Cycle 1 Basic Capability
Cycle 1 Basic Capability
UV plane/Beam Pattern
Most Compact Configuration Case (Lmax=160m, t = 10min)
UV Plane@345GHz
Beam@345GHz
y (m)
Antenna Configuration
Side lobes:
below 10%!
x (m)
Most Extend Configuration (Lmax=1000m, t = 10min)
UV Plane@345GHz
Beam@345GHz
y (m)
Antenna Configuration
Side lobes:
below 10%!
2012/6
x (m)
Town Meeting Cycle1 Capability, Policy, & Scince Case
11
ALMA Early Science Cycle1 Capability
- Observing Mode/Operation ・ Observation Mode
- No sub-array
- Mosaic (up to 150 field)
- No Polarization
- No solar Observation
M100
Mosaic (149 fields) at n=115GHz
・ Operation
- Target of Opportunity (ToO) and Director Discretionary Time (DDT)
Like standard proposals, these proposals must be submitted by the Cycle 1
proposal deadline.
- Only a few ToO proposals are likely to be among the highest ranked Cycle 1
proposals. The reaction time for its execution from triggered may be as long as 3
weeks. Shorter reaction times (few days) may be possible but are not guaranteed.
・ ACA (Atacama Compact Array)
ACA(7m array + Single Dish) operation start!
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
13
Cycle 1 Obs. Modes
ALMA Early Science Cycle1 Capability
- Additional Limitations -
• Up to five Science Goals per proposal.
* Science Goal: an Observational Setting (Spectral Setting/Sensitivity)
• Limitation of Target Number
Up to 15 individual sources (within 15 degrees on the sky) in a single
Science Goal
Pointing
Fields
• We can set multi-points observation to each target.
But total number of positions (fields) in each proposal
should be less than 151.
X
Target Position
•
•
•
•
The maximum observing time per proposal is 100 hours (Standard Program)
Cycle 1 observations will be scheduled mainly during nighttime.
All Cycle 1 Early Science observing will be conducted on a best effort basis.
Cycle 1 projects that have not been completed by the end of the cycle will
not be carried over to Cycle 2.
14
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
14
Accuracy
ALMA observatory provides calibrator (PI can define it).
• Accuracy of Absolute Amplitude Calibration
– Band 3: good to 5%
– Band 6/Band 7: good to 10%
– Band 9 : good to 20% (Goal)
• Positional Accuracy
about 1/10th of synthetic beam size
(It depends on noise level when a S/N ratio is low. )
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
15
ACA (Atacama Compact Array)
ACA is the tool for imaging of spread structure correctly. By combining the data of
12-m array and ACA array, we can recover Resolve Out which is a weak point of an
interferometer with keeping high spatial resolution.
• ACA System in Cycle1
– 9 x 7m antennas array
One configuration (baseline = 8.5m ～ 43m Baseline)
– 2～3台 x12m Single Dish (TP: Total Power Array)
• ACA Cycle 1 Capability
– In Cycle 1, we can use ACA in compact 12-m Array configurations (tminimum
baselines less than 25 m = Lmax < 558m) .
– TP array can not observe continuum emission.
12-m Array
Min Baseline
Max Baseline
ACA Allowed?
(7m-array can observe continuum)
Configuratio
(meters)
(meters)
n
– Observation time of ACA
C32-1
15
166
Yes
1
3 x (12-m Array observation time)
2012/6
C32-2
15
304
Yes
C32-3
21
443
Yes
C32-4
21
558
Yes
C32-5
26
820
No
1091
No
Town Meeting Cycle1 Capability,C32-6
Policy, & Scince
Case
43
16
参考
干渉計観測
干渉計観測とは、天体からのフラックス強度分布のフーリエ分解成
分を観測する装置。それを逆フーリエ変換で画像に戻します※。
天球
天球上の位置ベクトル r
※天体からの電磁波を相関機で干渉させると、ビジビリティー（visibility,
干渉縞の明暗強度)が得られます。簡単のために１次元uで考えると、
n (u )  a1a*2 
Source
In (r ) exp( 2iur )dr
最大
18km
相関機
となります(実際は２次元)。逆フーリエ変換し天体輝度分布 I(r) を得ます。
Point 1: アンテナ間距離（基線）が長いアンテナペアで観測すると空間周波数が高い
（小さな空間スケールのフーリエ成分）情報が得られます(最大基線長⇔空間分解能)。
 250m 
Spatial Resolution: 0.72"  345GHz  n: 観測周波数、Lmax:最大基線長



n
  Lmax 
Point 2: 最短基線長間の相関からはもっとも低い空間周波数情報が得られます。それよ
り低い空間周波数情報は得られないため、広がった空間構造成分は干渉計観測画像か
ら欠落します(最短基線長⇔Resolve Out)。
 345GHz   18m 
Resolve Outスケール：
n:観測周波数、Lmin:(実効)最短基線長
10.0" 
　


n
  Lmin 
Point 3: 単一鏡電波観測と異なり、干渉計観測では１つの座標の観測でも画像が得られ
ます。画像サイズはアンテナ口径で決まり各アンテナの視野(=Beam Size)と同じです。
視野サイズ（画像サイズ）： 14.9"  345GHz   12m 
n:観測周波数、Dantenna:アンテナ口径
2012/6
 n
  Dantenna 
Town Meeting Cycle1 Capability, Policy, & Scince Case
17
ACA (Atacama Compact Array)
ACA is the tool for imaging of spread structure correctly. By combining the data of
12-m array and ACA array, we can recover Resolve Out which is a weak point of an
interferometer with keeping high spatial resolution.
• ACA System in Cycle1
– 9 x 7m antennas array
Single configuration (baseline = 8.5m ～ 43m Baseline)
– 2 antennas x12m Single Dish (TP: Total Power Array)
• ACA Cycle 1 Capability
– In Cycle 1, we can use ACA in compact 12-m Array configurations (tminimum
baselines less than 25 m = Lmax < 558m) .
– TP array can not observe continuum emission.
12-m Array
Min Baseline
Max Baseline
ACA Allowed?
(7m-array can observe continuum)
Configuratio
(meters)
(meters)
n
– Observation time of ACA
C32-1
15
166
Yes
1
3 x (12-m Array observation time)
2012/6
C32-2
15
304
Yes
C32-3
21
443
Yes
C32-4
21
558
Yes
C32-5
26
820
No
1091
No
Town Meeting Cycle1 Capability,C32-6
Policy, & Scince
Case
43
19
ACA例
Demonstration of Data Combine (M100)
12m main array only
Very Large Telescope (VLT)
FORS
ALMA
band 3, CO(1-0) moment 1
http://almascience.eso.org/almadata/sciver/M100Band3/
2012/6
Town Meeting
Cycle1 Capability,
Policy, M100
& Scince Case
ALMA Science
Verification
Data:
20
ACA例
Demonstration of Data Combine (M100)
CO(1-0) Moment Map
12m array (Main array)
+
7m array
2012/6
12m Total Power (single dish)
On the fly mapping
Town Meeting Cycle1 Capability, Policy, & Scince Case
21
ACA例
Demonstration of Data Combine (M100)
12m array
Very Large Telescope (VLT)
FORS
mJy/Beam
CO(1-0) line profile
12m array + ACA
ALMA
ACA
band Recovering
3, CO(1-0)bymoment
1
12m array only
http://almascience.eso.org/almadata/sciver/M100Band3/
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Velocity
Case
[km/s]
22
ACA (Atacama Compact Array)
ACA is the tool for imaging of spread structure correctly. By combining the data of
12-m array and ACA array, we can recover Resolve Out which is a weak point of an
interferometer with keeping high spatial resolution.
• ACA System in Cycle1
– 9 x 7m antennas array
Single configuration (baseline = 8.5m ～ 43m Baseline)
– 2 antennas x12m Single Dish (TP: Total Power Array)
• ACA Cycle 1 Capability
– In Cycle 1, we can use ACA in compact 12-m Array configurations (tminimum
baselines less than 25 m = Lmax < 558m) .
– Observation time of ACA
12-m Array
Min Baseline
Max Baseline
ACA Allowed?
3 x observation time of 12m main array
Configuratio
(meters)
(meters)
n
→ Total observation time =
C32-1
15
166
Yes
obs time of 12m main array
C32-2
15
304
Yes
+ obs time of ACA
C32-3
21
443
Yes
C32-4
21
558
Yes
– TP array can not observe continuum.
C32-5
26
820
No
(7m-array can observe continuum)
1
2012/6
Town Meeting Cycle1 Capability,C32-6
Policy, & Scince
Case
43
1091
No
23
参考
Angular resolution and Maximum Angular Scale for the six Cycle
1 12-m Array configurations (Proposers Guide Table A.2)
たとえば、
- 周波数 345GHzの観測
-空間分解能0.4”
を要求する。
つまり、12mアンテナ配列 C32-3が観測で使われる配列である。
この配列では、5”を超える空間スケール構造はResolve Outする
（観測できない）。⇔ Max Ang Scale
そのような観測にはACAを使うことが必要となる。
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
24
参考
Angular resolution and Maximum Angular Scale for the six Cycle
1 12-m Array configurations (Proposers Guide Table A.2)
Angular resolution and maximum angular scales for continuum4
observations using the allowed 12-m Array & ACA combinations
5”以上に広がった構造を観測したいならばACAを用いるが、
さらに、13”までは7m array + 12m arrayで事足りる。
それ以上は、TP(12m single dish)を足さないとだめ。
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
25
Shadowing
Shadowing fraction vs. Declination for the two most compact configurations of
the 12-m Array and for the 7-m Array with a track duration of 2 hours (±1h HA).
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
26
Weather Condition
Cycle 1 observations will be scheduled mainly during nighttime.
The numbers indicate the percentage of time when the pwv is below 1 mm as a
function of Local Sidereal Time (LST) and week number beginning with January 1, 2013.
local midnight
ALMA Band
Band 3
Band 6
Band 7
Band 9
Fraction of time
100%
70%
40%
10%
shuotdown ALMA engineering time
Estimated maximum fraction of Early Science observing
time suitable for observations in each band in Cycle 1
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
27
Summary of Cycle1 Capablity
•
•
•
•
Call for Proposal is scheduled the end of May.
Proposal submission deadline is scheduled 12th of July.
Total observation time of 12m main array is 800hours.
Compared with Cycle0,
The sensitivity: x 2
The maximum spatial resolution: x 2.5 (1.2" - 0.19" @345GHz).
ACA is available.
Summary of Most Extended Configuration Lmax= 1km
( )<=Most Compact Lmax=160m
Band
Frequency
(GHz)
Angular Resolution
Maximum
Scale
Flux *1
(mJy)
Tb *2
(K)
Field of
View
3
100
0.57” (3.7”)
8.6” (25”)
0.06
2.4 (0.056)
62”
6
230
0.25” (1.6”)
3.7” (11”)
0.09
1.9 (0.047)
27”
7
345
0.16” (1.1”)
2.5” (7.1”)
0.15
2.9 (0.062)
18”
9
670
0.08” (0.55”)
1.3” (3.6”)
1.10
16 (0.35)
9”
1: 5 sigma continuum sensitivity (Bandwidth=8GHz) for 1hr
2: 3 sigma line sensitivity for 1 hr (1 km/s)
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
28
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
29
ALMAによるサイエンス例
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
30
The narrow dust ring around Fomalhaut
(Boley +12, Cycle0 paper)
Optical images trace micron-sized grains, which are
strongly affected by stellar radiation.
Radio continuum trace millimeter-sized grains, which
trace parent bodies.
=> ALMA high spatial resolution observation.
© ALMA (ESO/NAOJ/NRAO).
Visible image: the NASA/ESA (HST)
2012/6
ALMA obs. Suggest that debris confined by shepherd
planets is the most consistent with the ring’s
Town Meeting
Cycle1 Capability, Policy, & Scince Case
morphology.
31
[CII]158um emission at z=5
(Wagg+12, science verification)
• [CII] line detection in a pair of gas-rich galaxies
30
25
20
Flux Density [mJy]
Flux Density [mJy]
25
30
BR1202-0725 North
[CII]
z=4.69
15
10
5
0
BR1202-0725 South
[CII]
z=4.69
20
15
10
5
0
-5
-5
-600
-400
-200
0
200
Velocity Offset [km/s]
400
600
L[CII] = 10.0 x 109 L⊙
L⊙
-800
-600
-400
-200
0
Velocity Offset [km/s]
200
400
L[CII] = 6.5 x 109
[CII]-to-FIR ratio ~ 0.1 – 1%
The total observing time 25 min (on-source)
Follow up observation of K.Ohta +96, Iono +06
2012/6
20h SMA obs. => only 3 sigma (Iono + 06)
Town Meeting Cycle1 Capability, Policy, & Scince Case
32
[NII]205um emission at z=5
(Nagao+12, cycle 0 paper)
• The first measurement of the [NII]/[CII] flux ratio in
high-z galaxies (SMGs are chemically evolved)
2012/6
Total observingTown
timeMeeting
3.6hrsCycle1 Capability, Policy, & Scince Case
33
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
34
Materials
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
35
Cycle1 Continuum emission（Bandwidth = 8GHz）
Sensitivity
Cycle 1 (３２ 12m array)
t = 60 min
Dec
= -30deg
Most Compact (L=160m)
2012/6
Most Extended(L=1km)
Town Meeting Cycle1 Capability, Policy, & Scince Case
36
Review Process
• プロポーザルは、5つのCategoriesに分けられる。
• 各CategoryにあるReview Panelに振り分けられ、科学的審査される。
※各Categoryには 2つ程度のReview Panel(６名程度)が作られる。
• High priority proposalになる可能性が高いものは技術審査を受け、観測
実現不可なProposalを除く。
• 全プロポーザルで採点の高い順からHigh priority proposalを採択する。
ただし、以下の割合となるようにされる。
-22.5% for East Asia (EA);
-33.75% for Europe (EU);
-33.75% for North America (NA);
-10% for Chile.
Review Panelによる審査は11月に行われる予定である。
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
37
観測デモンストレーション
ALMAが提供するCASA(解析ツール)には観測シミュレーター
が付随している。視直径0.8secのタイタンを例にCycle1での
空間分解能をデモンストレーションすると、
最大160m基線長 (@345GHz)
最大1000m基線長 (@345GHz)
Titan表面のHST画像より
モデル作成
(Smith et al. 1996)
(注意) 今回は画像変換のデモンストレーション
2012/6
Town Meeting Cycle1 Capability, Policy, & Scince Case
38