** under construction ** 2016 january , 15

CollectionXmatchObscoreUsecase


Simple Query by Position

Show me a list of all data that satisfies:

  1. DataType=any
  2. contains RA=16.0 and DEC=40.0
These data would be searched on all VO services by sending the following query:

SELECT * FROM ivoa.Obscore WHERE
CONTAINS(POINT(‘ICRS’,16.0,40.0),s_region)=1

This query could be submitted to a remote TAP service using the curl application as follows (in this example a CADC TAP service is referenced):

curl -v -L -d "REQUEST=doQuery&LANG=ADQL&QUERY=select * from ivoa.ObsCore where CONTAINS(POINT('ICRS',16.0,40.0 ),s_region)=1" "http://www.cadc.hia.nrc.gc.ca/caom/sync"

More constraints are added in the following use-case (1.3).

Query by both Spatial and Spectral Attributes

Show me a list of all data that satisfies:

  1. DataType=Image
  2. Spatial resolution better than 0.3 arc seconds
  3. Filter = J or H or K
  4. RA between 16 hours and 17 hours
  5. DEC between 10 degrees and 11 degrees
Such a query needs to compute RA in degrees, extract information from Filter and adjust spectral intervals for search.

SELECT * FROM ivoa.Obscore
WHERE dataproduct_type=’image'
AND s_resolution < 0.3 AND s_ra > 240 AND s_ra < 255
AND s_dec > 10 AND s_dec < 11
AND (em_min > 2.1e-06 AND em_max < 2.4e-06)
OR(em_min >= 1.6e-06 AND em_max <= 1.8e-06)
OR(em_min >= 1.2e-06 AND em_max <= 1.4e-06)

A similar query could be submitted to a remote TAP service using the curl application as follows (in this example a CADC TAP service is referenced):

curl -v -L -d "REQUEST=doQuery&LANG=ADQL&QUERY=
select * from ivoa.ObsCore where dataproduct_type='image' AND s_resolution < .3 AND s_ra >240 and s_ra < 255 AND s_dec > 10 and s_dec < 11
and (em_min > 2.1e-06 AND em_max < 2.4e-06)
OR(em_min >= 1.6e-06 AND em_max <= 1.8e-06)
OR(em_min >= 1.2e-06 AND em_max <= 1.4e-06)"
"http://www.cadc.hia.nrc.gc.ca/caom/sync"

Query with energy, time, and position constraints

Show me all observations satisfying:

  1. DataType = any
  2. Energy includes 5 keV
  3. RA includes 16.00
  4. DEC includes +10
  5. Exposure time > 10 ks
SELECT * FROM ivoa.Obscore

WHERE em_min < 2.48E-10 AND em_max > 2.48 E-10

AND CONTAINS(POINT('ICRS',16.0,10.0),s_region) = 1

AND t_exptime > 10000

A.1 Discovering Images

A.1.2. Use case 1.2

Let me input a list of RA and DEC coordinates and show me spatially coincident observations satisfying:

  1. Imaging or spectroscopy data
  2. Includes one or more of the RA,DEC values in the list (LIST=SERVICE REQ)
  3. Includes both a wavelength in the range 5000-9000 angstroms AND an X-ray image (AND=SERVICE REQ)
This use case may need several steps to select images from X-RAY domain, select image and spectra on optical domain and compute the overlap.

It requires two functionalities from the service:

  • LIST=SERVICE REQ, to query on lists of positions given as input
  • AND=SERVICE REQ, to compute the intersection between two response lists.

A.1.3. Use case 1.3

Show me a list of all observations satisfying:

  1. DataType=Image
  2. Spatial resolution better than 0.3 arcseconds
  3. Filter = J or H or K
  4. RA between 16 hours and 17 hours
  5. DEC between 10 degrees and 11 degrees
SELECT * FROM ivoa.Obscore

WHERE dataproduct_type='image'

AND s_resolution < 0.3

AND (

( -- J band approximated

(em_min + em_max)/2 BETWEEN 1.234E-6 - 162E-9 AND 1.234E-6 + 162E-9

AND

(em_max - em_min) BETWEEN 0.5 * 162E-9 AND 1.5 * 162E-9

)

OR

( -- H band approximated

(em_min + em_max)/2 BETWEEN 1.662E-6 - 251E-9 AND 1.662E-6 + 251E-9

AND

(em_max - em_min) BETWEEN 0.5 * 251E-9 AND 1.5 * 251E-9

)

OR

( -- J band approximated

(em_min + em_max)/2 BETWEEN 2.159E-6 - 262E-9 AND 2.159E-6 + 262E-9

AND

(em_max – em_min) BETWEEN 0.5 * 262E-9 AND 1.5 * 262E-9

)

AND s_ra BETWEEN 16*15 AND 17*15

AND s_dec BETWEEN 10 and 11

A.1.4. Use case 1.4

Show me a list of all observations that satisfying:

  1. DataType=Image
  2. Wavelength=V or I or Z
  3. Spatial Resolution < 0.7 arcsec FWHM
  4. Exposure Time > 1000 seconds
  5. Data Quality: Fully Calibrated

A.1.5. Use case 1.5

Show me all data that satisfies:

  1. DataType=IFU
  2. DataQuality: Fully Calibrated
  3. ObjectClass=quasar (SERVICE REQ + NEEDS ANOTHER SERVICE (CATALOGUE)
IV. Redshift > 3
  1. Radio flux > 1 mJy
We assume here that data providers will expose IFU data using dataproduct_type=’cube’.

SELECT * FROM ivoa.Obscore

WHERE dataproduct_type='cube'

AND calib_level > 1

AND CONTAINS(POINT('ICRS', quasar_ra, quasar_dec), s_region) = 1

A.1.6. Use case 1.6

For an input list of RA, DEC, Modified Julian Date (MJD), show me all data that satisfies (LIST=SERVICE REQ)

  1. DataType=imaging
  2. RA,DEC include the value of the list and Observation date is within 1 day of the MJD value
SELECT * FROM ivoa.Obscore

WHERE dataproduct_type='image'

AND CONTAINS(POINT('ICRS',user_ra,user_dec), s_region) = 1

AND | (t_max + t_min)/2 – user_date | < 1 d

A.2. Discovering spectral data

A.2.1. Use case 2.1

Show me a list of all data that satisfies:

  1. DataType=Spectrum
  2. Energy spans 1 to 5 keV
  3. Total counts in spectrum > 100
IV. Exposure time > 10000 seconds
  1. Data Quality: Fully Calibrated

A.2.2. Use case 2.2

Show me a list of all data that satisfies:

  1. DataType=Spectrum
  2. Wavelength includes 6500 angstroms
  3. Spectral Resolution better than 15 angstroms
IV. Spatial Resolution better than 2 arcseconds FWHM
  1. Exposure Time > 3600 seconds
VI. Data Quality = Any

SELECT * from ivoa.Obscore

WHERE dataproduct_type='spectrum'

AND em_min < 650E-9

AND em_max > 650E-9

AND em_res_power > 6500/15.

AND s_resolution < 2

AND t_exptime > 3600

A.2.3. Use case 2.3

Show me a list of all data that satisfies:

  1. Emission line width Halpha > 2000 km/s FWHM (SERVICE REQ+NEEDS OTHER SERVICE)

A.3. Discover multi-dimensional observations

A.3.1. Use case 3.1

Show me a list of data with:

  1. DataType=cube (IFU spectroscopy?)
  2. RA,DEC includes value RA1,DEC1
  3. Field size > 100 square arcseconds
IV. DataSensitivity = deep
  1. Spectral resolution better than 5 angstroms FWHM

A.3.2. Use case 3.2

Show me a list of all data that satisfies:

  1. DataType=cube with 3 dimensions
  2. Axes includes Velocity
  3. Axes includes RA
IV. Axes includes DEC
  1. Velocity Resolution better than 50 km/s
VI. RA includes 16.000

VII. Dec includes +41.000

NB: in this case optional data model fields related to redshift axis can be used using redshift_ucd= spect.DopplerVeloc, for instance.

A.3.3. Use case 3.3

Show me a list of all data that satisfies:

  1. I. DataType=cube
  2. II. RA includes 16.00
  3. III. Dec includes +41.00
  4. IV. Wavelength includes 6500 angstroms
  5. V. Wavelength includes 4000 angstroms
  6. VI. Spectral resolution better than 5 angstroms
  7. VII. Exposure time more than 3600 seconds
  8. Data Quality: Fully Calibrated

A.3.4. Use case 3.4

Show me a list of all data that satisfies:

  1. DataType=Cube with 3 dimensions
  2. Axes includes FREQ
  3. Axes includes RA
IV. Axes includes DEC
  1. Velocity Resolution better than 1 km/s
VI. RA includes 83.835000

VII. Dec includes -5.014722

  1. Rest Frequency = 345.795990 GHz
IX. VLSRK in the range [6.0, 10.0]

A.3.5. Use case 3.5

Show me a list of all data that satisfies:

  1. DataType=Cube with 3 dimensions
  2. Axes includes FREQ
  3. Axes includes RA with > 100 pixels
  4. Axes includes DEC with > 100 pixels
  5. Frequency extent > 500 MHz
  6. Rest Frequency = 345.795990 GHz appears in band
  7. The redshift is not specified, but should default to zsource for the target.
NB: I to V are supported in ObsTAP; VI and VII need target redshift properties extracted from catalogs

A.3.6. Use case 3.6

Show me a list of all data that satisfies:

  1. DataType=Cube with 3 dimensions
  2. Axes includes FREQ
  3. Axes includes RA
  4. Axes includes DEC
  5. Frequency resolution < 10 MHz
  6. Rest Frequency = 337.2966 GHz appears in band
  7. Any observation that could have detected a line at this rest frequency from any target, using the nominal redshift for the target.

A.3.7. Use case 3.7

Show me a list of all data that satisfies:

  1. DataType=Cube with 3 dimensionsAxes includes FREQ
  2. Axes includes RA
  3. Axes includes DEC
  4. Frequency resolution < 10 MHz
  5. Rest Frequency in (213.36053, 256.0278, 298.6908925, 341.350826, 384.0066819, 426.6579505, 469.3041221, 511.944687, 554.5791355) GHz appears in band
  6. Any observation that could have detected HCS+ (list of transition rest frequencies given above) from any target, using the nominal redshift for the target.

A.3.8. Use case 3.8

Show me a list of all data that satisfies:

  1. DataType=Cube with 4 dimensions
  2. Axes includes FREQ
  3. Spatial axes contain more than 100 pixels
  4. Axes includes STOKES
  5. Frequency resolution < 1 MHz
  6. Rest Frequency = 345.795990 GHz appears in band
NB: Need for a polarisation axis

A.3.9. Use case 3.9

Looking for moving targets:

  1. Show me the names of all the objects that have moving coordinates (i.e. no fixed RA, DEC position).

A.3.10. Use case 3.10

Show me a list of all data that satisfies:

  1. DataType=Cube with 3 dimensions
  2. Axes includes WAVE
  3. Axes includes more than 200 pixels along each spatial axis
  4. Spatial resolution better than 2 arcsec
  5. For a selected list of SDSS objects

A.4. Discovering time series

A.4.1. Use case 4.1

Show me a list of all data which satisfies:

  1. DataType=TimeSeries
  2. RA includes 16.00 hours
  3. DEC includes +41.00
  4. Time resolution better than 1 minute
  5. Time interval (start of series to end of series) > 1 week
  6. Observation data before June 10, 2008
  7. Observation data after June 10, 2007

A.4.2. Use case 4.2

This use-case is added in ObsCore 1.1 to search for time series against the number of time slots and be sure to have enough samples along the time axis

Show me a list of all data which satisfies:

  1. DataType=TimeSeries
  2. RA includes 16.00 hours
  3. DEC includes +41.00
  4. Time resolution better than 1 minute
  5. Time interval (start of series to end of series) > 1 year
  6. Number of time slots > 50

A.4.3. Use case 4.3

Show me a list of all data matching a particular event (gamma ray burst) in time interval and space:

  1. DataType=TimeSeries
  2. RA includes 16.00 hours
  3. DEC includes +41.00
IV. Time start > MJD 55220. and Time stop < MJD 55221
  1. Number of time slots > 1000

A.5. Discovering event lists

A.5.1. Use case 5.1

Show me a list of all event lists observed for a particular phenomenon with constraints on space and time coverage like:

  1. DataType=event list
  2. RA includes target_RA
  3. DEC includes target_DEC
  4. Time resolution better than 1 minute
  5. Exposure Time > 100000s
  6. Oservation data after June 10, 2007
  7. Observation data before June 10, 2008

A.5.2. Use case 5.2

Show me a list of all event lists observed in the XMM data collection within the region covered by a particular image of GALEX data collection.

  1. DataType=event list
  2. Region contains polygon P1 extracted from the foot print of a GALEX image
  3. Data collection= XMM
  4. Instrument=EP
Topic revision: r2 - 2016-01-19 - MireilleLouys
 
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