The ALMA Observing Preparation Tool

Transcription

1 The ALMA Observing Preparation Tool Atacama Large Millimeter/submillimeter Array Expanded Very Large Array Robert C. Byrd Green Bank Telescope Very Long Baseline Array

2 Video versions of this material: 2

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4 Click!"#$#! 4

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6 Registering with User Portal To register for the user portal, go to either: (saves one step) Go to the User Portal to access: ALMA info and news Call for Proposals ALMA tools and documentation Helpdesk Project Tracker ALMA Science Archive 6

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8 Launch the Application A couple of dialog boxes will pop up 8

9 Hover over these icons to get help New Proposal (Phase I) Open project from Archive New Phase I Science Goal Sensitivity Calculator Help! Contextual help on proposal workflow 9

10 Tips Be alert to the presence of sliders, some information may be off-screen 10

11 Tips Stippled edges can be dragged to resize panes 11

12 Tips Arrowheads maximize and minimize panes 12

13 A walk through of a simple example Observe molecular gas in NGC 1097 Use CO (1-0) emission line Rest frequency: GHz Band 3 (2.6 mm) Size of NGC 1097 is 9 x 6 The field of view for a single pointing at 115 GHz is ~ 45 Single pointing of the nucleus! During ES, up to 50 pointing mosaics are allowed. %&'("#)*+#,!-#./! 01233/!-.)#4*'#! NGC 1097 from S 4 G, Sheth et al

14 Proposal Preparation Workflow Using the Contextual help Click through the tabs and follow the instructions on the left. 14

15 Fill out these relevant fields 15

16 Fill out these relevant fields Proposal Title Abstract 16

17 Fill out these relevant fields { Click here to set PI and co-is 17

18 Type in the name or username An error may pop up 18

19 Finding Help If you get stuck on any step, look for the? Icon Click on it to get help. 19

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21 Attaching the Sci / Tech Justification as a single PDF file 21

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23 Click on this turn-key to continue 23

24 At any point you can check whether your proposal passes validation Validation is required before proposal can be submitted 24

25 Press on Science Goal tab to create a science goal 25

26 What is a Science Goal in the OT? A science goal is: One correlator / front end setup in one ALMA band spectral windows, rest freq, polarization products, line/continuum modes Subject to one set of control parameters spatial resolution, sensitivity, dynamic range Using one mapping strategy Mosaic or single-pointing And one calibration strategy User or system-defined Applied to an arbitrary set of sky targets (field centers) Each with its own LSR velocity In ES all windows in one science goal must have the same bandwidth and channel spacing 26

27 Describe your science goal if you wish for the technical assessors (not required) Enter in Source name 27

28 Make sure and double check the coordinates. 28

29 Check the velocity used -> observing frequency. 29

30 Click on Spatial Tab to visualize observations Red text indicates incorrect or missing value 30

31 Clicking here opens the visualizer panel Press Query to get the image from pre-loaded servers - or - Load your own image* (Galactic coordinates won t work yet) 31

32 Placing beams on an image (the graphical method) Enter frequency 32

33 For Calibration Set up: Unless you have a strong reason for choosing User-defined calibration, then leave this as Systemdefined calibration. 33

34 Currently supported modes for Cycle 0 Press here to add a line 34

35 e.g. Type in CO A window that can search Splatalogue will open. 35

36 Double click on the transition Now, the line list will be limited to those that can be observed at same time! Transition moves into this window Press here to accept selection 36

37 Your chosen Line is now loaded into the Setup: 37

38 Click on Spectral Tab to visualize observations Atmospheric transmission ALMA Community Day, Harvard-Smithsonian Center for Astrophysics, April 20,

39 LO CO line Band 3 LO Range Sidebands Press here to change resolution 39

40 Select correlator mode Trade-off between bandwidth & resolution 40

41 Can add up to 4 spectral windows must have same resolution and bandwidth in Cycle 0 Location of windows is constrained 41

42 Summary: A very versatile tool with lots of options Note that the colors can be changed from the Preferences: 42

43 Request the resolution and sensitivity you need for your Science Goal 43

44 Back to our example of NGC 1097 To get a 10σ detection on the faintest emission in the map requires ~10 mjy/beam in a 10 km/s channel. The ALMA correlator gives km/s channels; we will bin 8 channels to get to 10 km/s. So required sensitivity in one correlator channel ~ 10 mjy/bm * sqrt (8) ~ 28 mjy/beam Nobeyama maps of NGC 1097 (Kohno et al. 2003) 44

45 Back to our example of NGC ~ 110pc Sufficient to resolve the ring Press here to get an idea of how long it will take to do this 45

46 ALMA with 16 x 12m antennas is very fast! BUT be aware that your UV-coverage may not be ideal we recommend that you use simdata to check 46

47 Back to our example of NGC

48 Time allocation for the proposal will be the Total Estimated time. 48

49 Validation Step 49

50 List of problems 50

51 See also: known issues 51

52 almascience.nrao.edu science.nrao.edu/alma 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. 52