alma during early science
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ALMA During Early Science
National Radio Astronomy Observatory - NAASCCharlottesville, Virginia
ALMAThe Breadth of ALMA
Science • Image the redshifted dust continuum emission from evolving galaxies at epochs of formation as early as z = 10.
• Probe the cold dust and molecular gas of nearby galaxies, allowing detailed studies of the interstellar medium in different galactic environments, the effect of the physical conditions on the local star formation history, and galactic structure.
• Reveal the details of how stars form from the gravitational collapse of dense cores in molecular clouds. The spatial resolution of ALMA will allow the accretion of cloud material onto an accretion disk to be imaged, and will trace the formation and evolution of disks and jets in young protostellar systems. For older protostars and pre-main sequence stars, ALMA will show how (proto)planets sweep gaps in circumstellar and debris disks.
• Uncover the chemical composition of the molecular gas surrounding young stars, including establishing the role of the freeze-out of gas-phase species onto grains, the re-release of these species back into the gas phase in the warm inner regions of circumstellar disks, and the formation of complex organic molecules
• Image the formation of molecules and dust grains in the circumstellar shells and envelopes of evolved stars, novae, and supernovae.
• Refine dynamical and chemical models of the atmospheres of planets in our own Solar System, and provide unobscured images of cometary nuclei, hundreds of asteroids, Centaurs, and Kuiper Belt Objects.
ALMACycle 0• Sixteen 12m Antennae• Four Bands in the frequency range 84-720 GHz• A Compact Configuration, with a min/max
baseline of ~18m/125m (largest observable scale ~ 21” at 100 GHz)
• An Extended Configuration, with a min/max baseline of ~36m/400m (max angular resolution ~ 0.23” at 675 GHz)
• Single pointing + mosaics (up to 50 pointings)• a number of spectral/continuum correlator
modes, with bandwidths from 58.6 MHz and 2 GHz per baseband
• Sources as far North as declination ~ 40o can be observed
• Observations of moving targets (except the Sun) supported
ALMACycle 0 ALMA Observing Frequencies
Band 3 6 7 9
ν (GHz) 84-116 211-275 275-373 602-720λ (mm) 3.6-2.6 1.4-1.1 1.1-0.8 0.5-0.42Angular Resolution (“) 1.56 0.68 0.45 0.23Maximum Observable Scale (“) 21 9 6 3
Primary Beam (“) 62 27 18 9Continuum Sensitivity (mJy/beam) 0.14 0.20 0.37 3.2
“Extended” Angular Resolution (“) ~ 0.5” x (300 / ν GHz) x (0.400 km / max baseline)“Compact” Maximum Scale (“) ~ 7”x (300 / ν GHz) x (0.018 km / min baseline)12m Primary Beam (“) ~ 20.3” x (300 / ν GHz)Sensitivity = 5σ in 1 hour (dual polarization mode)
ALMAALMA Bands & Atmospheric
Transmission
Cycle 0 Bands
•Resolution increases with increasing frequency
•Weather (& sensitivity) degrade with increasing frequency
1.3mm pwv0.5mm pwv
ALMAExample Correlator
Modes
ModeEffectiveBandwidth(GHz)
No. of channels
SpectralResolution(kHz)
Polarization
7 1.875 3840 488 Dual9 469 3840 122 Dual12 58.6 3840 15 Dual
E.g., for Mode 7:~6600 km/s bandwidth per spectral window (x 2 windows )~2 km/s resolution
Dual polarization cuts the needed integration time in half.
Arp 220
C2H
HCN
HCO+
HNC
2 windows
ALMA
Telescope altitude diameter No. Area νmax
(feet) (m) Dishes (m2) (GHz)
NMA 2,000 10 6 470 250CARMA 7,300 3.5/6/10 8/9/6 800 250IRAM PdB 8,000 15 6 1060 250SMA 13,600 6 8 230 650ALMA (ES) 16,400 12 16 1800 720
ALMA Full ScienceALMA 16,400 12 54 6100 950ACA 16,400 7 12 490 950
EVLA 7,050 25 27 13250 43
Comparison with existing arrays
Spectral Coverage
3 4 6 7 8 9 10
ALMAComparison with existing arrays
CARMA
SMA
IRAM PdBI ALMA Early Science
8 (28)
23 (253)
6 (15)16 (120)64 (2016)
Collecting Area & Number of
Baselines
(from D. Wilner)
ALMA
Hot core of G34.26+0.15: at 3mm - lots of molecular lines detected in 2 hours.
ALMA test Data (5-6 Ant)
ALMA
β Pictoris disk: Herschel on left and 870 micron dust emission from ALMA
ALMA Data
ALMA
NGC 253: Band 6: CO (2→1) and Band 9: Continuum + CO(6→5)
ALMA Data
ALMA
BRI 0952-0115: (z =4.43) Ionized Carbon (CII @ rest-frame158 μm) detected in 1 hour
ALMA Data
ALMACycle 0
• Call for Proposals issued 31 March 2011• Proposal Deadline = 15:00 UT on 30 June
2011• 500-700 hours of observations in Cycle 0• North American time = 33.75% • Proposal Types: Standard (≤100 hours) &
Target of Opportunity• Think of science that can be done in a few
hours of observing time
ALMAPhase I Tools
Screenshot of the Proposal Preparation Tool
•Observing Tool (OT)
•SIMDATA•Sensitivity
Calculator•Splatalogue
ALMAPhase I Tools
•Observing Tool (OT)
•SIMDATA•Sensitivity
Calculator•Splatalogue
ALMAPhase I Tools
•Observing Tool (OT)
•SIMDATA•Sensitivity
Calculator•Splatalogue
Screenshot of Sensitivity Calculator in the OT
ALMAPhase I Tools
•Observing Tool (OT)
•SIMDATA•Sensitivity
Calculator•Splatalogue
Screenshot of Splatalogue
ALMAProposal Checklist
• Read relevant documentation (CfP Guide, Primer)• Create an ALMA account by registering at the
Science Portal• Download the Observing Tool (OT) & related
guides• Prepare the Science & Technical Cases (PDF file)• Prepare Science Goals (sources, frequency &
correlator setup, integration times) within the OT • Make use of the Helpdesk & the Knowledgebase
ALMANRAO User Support
NRAO User Support
ALMAThe North American ALMA Science
Center
• located in Charlottesville, VA
• User support for proposal preparation & post-observation
• Support user visits to NAASC
• NRAO Page Charge Support
• Organize ALMA workshops
http://science.nrao.edu/alma/index.shtml
ALMAThe North American ALMA Science
Center
NAASC Postdocs
Manuel Aravena, Rachel Friesen, Violette Impellizzeri, Brian Kent, Amy Kimball, Nuria Marcelino,
Robin Pulliam
The Atacama Large Millimeter/sub-millimeter Array (ALMA), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan. ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.
ALMA
Date Milestone
31 March 2011 Cycle 0 CfP & release of Observing Tool
29 April 2011 Cycle 0 Proposal Notice of Intent deadline
1 June 2011 Opening of archive for proposal submission
30 June 2011 Proposal deadline
July - Sept 2011
Technical AssessmentsScience-Themed ALMA Review Panels (ARPs)ALMA Proposal Review Committee (APRC)
mid-Sept 2011 Announce Results30 September 2011
Anticipated start of ALMA Cycle 0 observing
February 2012 Anticipated one month engineering shutdown
30 June 2012 Anticipated end of ALMA Cycle 0
Key Cycle 0 dates
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