Information on Service 'M) Apertif DR1 - Polarization images and cubes'

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Further access options are discussed below

This service query provides for each observation A multi-frequency Stokes V image and Stokes Q and U cubes with a frequency resolution of 6.25 MHz. The Stokes V images are 3.4°×3.4°(3073×3073 pixels, with 4′′/pixel) while the Stokes Q and U cubes have a spatial extent of 2.7°×2.7°(2049×2049 pixels, with 4′′/pixel). These images are 1.1°×1.1°(661×661 pixels, with 6′′/pixel), which extend well beyond the 10% primary beam level. The angular resolution of the imaging survey observations is ∼ 15′′×15′′/sin(δ). Please find more details in the Apertif DR1 documentation

For a list of all services and tables belonging to this service's resource, see Information on resource 'Apertif DR-1'

Overview

You can access this service using:

This service is published as follows:

local means it is listed on our front page, ivo_managed means it has a record in the VO registry.

Other services provided on the underlying data include:

Spatial Coverage

Input Fields

The following fields are available to provide input to the service (with some renderers, some of these fields may be unavailable):

NameTable Head DescriptionUnitUCD
beam_number Beam number Beam number N/A meta.id;instr.beam
FORMAT Output format Requested format of the image data N/A N/A
hFORMAT Output format Requested format of the image data N/A N/A
hINTERSECT Intersection type Relation of image and specified Region of Interest. N/A N/A
hPOS Position ICRS Position, RA,DEC, or Simbad object (e.g., 234.234,-32.45) deg pos.eq
hSIZE Field size Size in decimal degrees (e.g., 0.2 or 1,0.1) deg N/A
INTERSECT Intersection type Relation of image and specified Region of Interest. N/A N/A
max_d Max distance from the center Maximum distance to the center of the images deg N/A
MAXREC Match limit Maximum number of records returned. Pass 0 to retrieve service parameters. N/A N/A
obsid ObsId Observation id N/A meta.id
POS Position ICRS Position, RA,DEC decimal degrees (e.g., 234.234,-32.46) deg pos.eq
RESPONSEFORMAT Output Format File format requested for output. N/A meta.code.mime
SIZE Field size Size in decimal degrees (e.g., 0.2 or 1,0.1) deg N/A
target Field Name Name of the field. Matches also partial input (e.g. m1403+5324 or 1403+5324). N/A meta.id
VERB Verbosity Exhaustiveness of column selection. VERB=1 only returns the most important columns, VERB=2 selects the columns deemed useful to the average user, VERB=3 returns a table with all available columns. N/A N/A

Default Output Fields

The following fields are contained in the output by default. More fields may be available for selection; these would be given below in the VOTable output fields.

NameTable Head DescriptionUnitUCD
_r Dist Distance of the queried position to the center of the image arcmin pos.distance
accref Product key Access key for the data N/A N/A
accsize File size Size of the data in bytes byte VOX:Image_FileSize
beam_frac Beam frac. N/A N/A stat.value
beam_number Beam Number of the beam N/A meta.id;instr.beam
bmin bmin N/A N/A stat.value
centerAlpha Ctr. RA Approximate center of image, RA deg POS_EQ_RA_MAIN
centerDelta Ctr. Dec Approximate center of image, Dec deg POS_EQ_DEC_MAIN
dateObs Obs. date Epoch at midpoint of observation d VOX:Image_MJDateObs
freqMax max. Frequency Maximum frequency MHz em.freq
freqMin min. Frequency Minimum frequency MHz em.freq
FT_max FT max N/A N/A stat.value
imageTitle Title Synthetic name of the image N/A VOX:Image_Title
instId Instrument Identifier of the originating instrument N/A INST_ID
mime Type MIME type of the file served N/A meta.code.mime
n_channels # channels Number of channels N/A em.bin
noise_frac Noise frac. N/A N/A stat.value
obsid ObsId Unique id N/A meta.id
peak_inner Peak Inner N/A N/A stat.value
pixelScale Scales The pixel scale on each image axis deg/pix VOX:Image_Scale
polarization Polarization Polarization Stokes N/A phys.polarization.stokes
pub_did P. DID Dataset identifier assigned by the publisher N/A meta.id;meta.main
related_products Related products Link related products for the observation N/A meta.ref.url
sigma_in Sigma in N/A N/A stat.value
sigma_out Sigma out N/A N/A stat.value
target Field Name of the field N/A meta.id
valid Passed validation Whether or not the dataset has passed validation N/A meta.code.qual

VOTable Output Fields

The following fields are available in VOTable output. The verbosity level is a number intended to represent the relative importance of the field on a scale of 1 to 30. The services take a VERB argument. A field is included in the output if their verbosity level is less or equal VERB*10.

NameTable Head DescriptionUnitUCD Verb. Level
centerAlpha Ctr. RA Approximate center of image, RA deg POS_EQ_RA_MAIN 0
centerDelta Ctr. Dec Approximate center of image, Dec deg POS_EQ_DEC_MAIN 0
imageTitle Title Synthetic name of the image N/A VOX:Image_Title 0
dateObs Obs. date Epoch at midpoint of observation d VOX:Image_MJDateObs 0
accref Product key Access key for the data N/A N/A 1
target Field Name of the field N/A meta.id 1
related_products Related products Link related products for the observation N/A meta.ref.url 1
sigma_in Sigma in N/A N/A stat.value 8
sigma_out Sigma out N/A N/A stat.value 8
FT_max FT max N/A N/A stat.value 8
peak_inner Peak Inner N/A N/A stat.value 8
bmin bmin N/A N/A stat.value 8
beam_frac Beam frac. N/A N/A stat.value 8
noise_frac Noise frac. N/A N/A stat.value 8
bandpassId Bandpass Freeform name of the bandpass used N/A VOX:BandPass_ID 10
accsize File size Size of the data in bytes byte VOX:Image_FileSize 11
pixelScale Scales The pixel scale on each image axis deg/pix VOX:Image_Scale 12
type Type N/A N/A meta.id 12
instId Instrument Identifier of the originating instrument N/A INST_ID 15
pixelSize Axes Lengths Number of pixels along each of the axes pix VOX:Image_Naxis 15
pub_did P. DID Dataset identifier assigned by the publisher N/A meta.id;meta.main 15
_r Dist Distance of the queried position to the center of the image arcmin pos.distance 20
mime Type MIME type of the file served N/A meta.code.mime 20
nAxes #axes Number of axes in data N/A VOX:Image_Naxes 20
refFrame Ref. Frame Coordinate system reference frame N/A VOX:STC_CoordRefFrame 20
wcs_equinox Equinox Equinox of the given coordinates yr VOX:STC_CoordEquinox 20
wcs_projection Proj. FITS WCS projection type N/A VOX:WCS_CoordProjection 20
wcs_refPixel Ref. pixel WCS reference pixel pix VOX:WCS_CoordRefPixel 20
wcs_refValues Ref. values World coordinates at WCS reference pixel deg VOX:WCS_CoordRefValue 20
wcs_cdmatrix CD matrix FITS WCS CDij matrix deg/pix VOX:WCS_CDMatrix 20
bandpassUnit Bandpass unit Unit of bandpass specifications (always m). N/A VOX:BandPass_Unit 20
bandpassRefval Band Ref. Characteristic quantity for the bandpass of the image m VOX:BandPass_RefValue 20
bandpassHi Band upper Upper limit of the bandpass (in BandPass_Unit units) m VOX:BandPass_HiLimit 20
bandpassLo Band lower Lower limit of the bandpass (in BandPass_Unit units) m VOX:BandPass_LoLimit 20
pixflags P. Flags Flags specifying the processing done (C-original; F-resampled; Z-fluxes valid; X-not resampled; V-for display only N/A VOX:Image_PixFlags 20
coverage Coverage Field covered by the image deg N/A 20
obsid ObsId Unique id N/A meta.id 20
valid Passed validation Whether or not the dataset has passed validation N/A meta.code.qual 20
task_id Task id ID of the task N/A meta.id 20
beam_number Beam Number of the beam N/A meta.id;instr.beam 20
freqMin min. Frequency Minimum frequency MHz em.freq 20
freqMax max. Frequency Maximum frequency MHz em.freq 20
n_channels # channels Number of channels N/A em.bin 20
pipeline_name Pipeline name Name of the used pipeline N/A N/A 20
pipeline_version Pipeline version Version of the used pipeline N/A N/A 20
polarization Polarization Polarization Stokes N/A phys.polarization.stokes 20

Copyright, License, Acknowledgements

APERTIF-DR1 is licensed under the Creative Commons Attribution 3.0 License

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