diff --git a/Appendix.tex b/Appendix.tex index 1d1fc20..5a29907 100644 --- a/Appendix.tex +++ b/Appendix.tex @@ -25,11 +25,10 @@ \subsection{Use case - s\_resolution\_min} \begin{verbatim} SELECT * FROM ivoa.obscore NATURAL JOIN ivoa.obscore_radio -WHERE -s_resolution_min > 0.017 - AND (target_name = 'Virgo A' OR +WHERE s_resolution_min > 0.017 +AND (target_name = 'Virgo A' OR CONTAINS(POINT(s_ra, s_dec),CIRCLE,187.7059308,+12.3911232,0.25)) = 1)) -AND (scan_mode = 'raster map' OR scan_mode = 'on-the-fly map') +AND (scan_mode = 'raster map' OR scan_mode = 'on-the-fly map') \end{verbatim} \subsection{Use case - s\_resolution\_max} @@ -44,16 +43,14 @@ \subsection{Use case - s\_resolution\_max} SELECT * FROM ivoa.obscore NATURAL JOIN ivoa.obscore_radio WHERE s_resolution_max < 0.017 -AND - (target_name = 'IC443' OR +AND (target_name = 'IC443' OR CONTAINS(POINT(s_ra,s_dec),CIRCLE(94.2500000,+22.5699997,0.25)) = 1)) AND (scan_mode = 'raster map' OR scan_mode = 'on-the-fly map') \end{verbatim} \subsection{Use case - s\_fov\_min - large field of views} \label{sec:s_fov_min} -\textit{Select any dataset obtained in map scanning mode (raster or on-the-fly) with minimum field of view larger than 0.8 degree. For instance, investigate the region surrounding cluster Abell 194.} - +\textit{Select any dataset obtained in map scanning mode (raster or on-the-fly) with minimum field of view larger than 0.8 degree. For instance, investigate the region surrounding cluster Abell 194.}\\ Show me all datasets satisfying:\\ I. Minimum FOV > 0.8 deg \\ II. Target name = Abell 194 or position inside 15 arcmin from 21.5054167, -1.3672221 @@ -138,12 +135,13 @@ \subsection{Use case - frequency selection for images } % Should these restrict the dataproduct_type? \subsection{Use case - high resolution data around FRB targets } -\textit{Give me high-resolution data on possible persistent radio sources within an arc second of FRB 121102.} \\ Show me all datasets satisfying: +\textit{Give me high-resolution data on possible persistent radio sources within an arc second of FRB 121102.} \\ Show me all datasets satisfying: \\ % add constraints I. Source close to FRB 121102 \\ II. Spatial resolution < 1 arcsec \begin{verbatim} -SELECT * FROM ivoa.obscore NATURAL JOIN ivoa.obscore_radio +SELECT * FROM ivoa.obscore +NATURAL JOIN ivoa.obscore_radio WHERE CONTAINS(POINT(s_ra,s_dec),CIRCLE(82.99458,33.14794,0.0003)) = 1 AND s_resolution_max < 0.001 \end{verbatim} @@ -151,11 +149,12 @@ \subsection{Use case - high resolution data around FRB targets } \subsection{Use case - reasonable fidelity} \textit{Give me data on extended HI emission around the source 3C84 that can -be imaged with reasonable fidelity.}\\ Show me all datasets satisfying: +be imaged with reasonable fidelity.}\\ +Show me all datasets satisfying: \\ %add constraints I. Region contains source 3C84 \\ -II. Maximum angular scale > 1arcsec -III. uv plane is filled at more than 0.2 +II. Maximum angular scale > 1arcsec \\ +III. uv plane is filled at more than 0.2\\ IV. Estimated uv eccentricity < 0.75 \begin{verbatim} SELECT * FROM ivoa.obscore diff --git a/ObsCoreExtensionForRadioData.tex b/ObsCoreExtensionForRadioData.tex index a4a2fad..5aaa240 100644 --- a/ObsCoreExtensionForRadioData.tex +++ b/ObsCoreExtensionForRadioData.tex @@ -110,7 +110,7 @@ \section{Introduction} Its goal is to clarify how ObsCore metadata can be used in the radio context and to add new specific features to the existing ObsCore metadata. -\section{Radio data specifities from the Data Discovery point of view} +\section{Radio data specificities from the Data Discovery point of view} \label{sec:specificities} @@ -186,8 +186,8 @@ \subsection{Visibility data } interferometric images through inverse Fourier algorithms. Each visibility measurement corresponds to an interferometric fringe system on the sky. -The imaging algorithms include a possibility to set the center of the -reconstructed image, setting this direction as a phase reference. Visibilities +The imaging algorithms include a calibration step that requires fixing the +center of the reconstructed image as a phase reference. Visibilities are usually represented in a spatial frequency plane, called the \emph{uv} plane, whose orientation is perpendicular to phase reference direction. The instantaneous PSF (Point Spread Function) of an interferometer is the Fourier transform of all baselines @@ -229,7 +229,7 @@ \subsection{Visibility data } Radio astronomers also check the quality of the visibility data by looking at some maps/plots derived from the observed quantities or of the observational parameters. The \emph{uv} coverage map can show how complete and regular is the sampling in -the \emph{uv} plane and give an hint of resolution and maximum angular scale. +the \emph{uv} plane and gives an hint of resolution and maximum angular scale. The visualisation of the dirty beam, which is the Fourier transform of the \emph{uv} sampling function gives an hint of the intrinsic quality of possible reconstruction. These maps side products cannot be represented by an ObsDataset class from ObsCore, with spatial axis on the sky, @@ -241,7 +241,7 @@ \subsection{Visibility data } (or maximum antenna diameter), the number of antennas and the minimum and maximum distance between antennas in the array. -In addition to these specifities most of the scan modes shown in Fig. ~\ref{fig:SD} also +In addition to these specificities most of the scan modes shown in Fig. ~\ref{fig:SD} also apply to some interferometry observations and should be described. \section{ObsCore attributes definition valid for radio data} @@ -276,7 +276,7 @@ \subsection{s\_fov} %mid value of the spectral range receiver nominal wavelength and D coincides with the telescope diameter (SD case) or with the largest diameter of the array antennae or telescopes (interferometric case). In interferometry, the correlator can also restrict the field of view depending on the trade-off set to build the signal. -Nominal wavelength SHOULD be taken as the mid value of the spectral range except if data providers have good reasons to propose another value which should be documented in the FIELD DESCRIPTION tag in that case. +Nominal wavelength SHOULD be taken as the mid value of the spectral range except if data providers have good reasons to propose another value. This should be documented in this column's description metadata. \subsection{s\_resolution} \label{sec:res} @@ -339,7 +339,7 @@ \section{ObsCore extension specific for radio data} \subsection{Spatial parameters} -For extended spectral range datasets \emph{s\_fov\_min, s\_fov\_max} are estimated like in the typical value case (see subsection ~\ref{sec:fov}). +For extended spectral range datasets \emph{s\_fov\_min, s\_fov\_max} are estimated like in the typical value case (see subsection ~\ref{sec:fov}).\\ In the case of SD pointed observations with mono-feed receivers and the majority of interferometric observations the minimum and maximum $\lambda$ values in the spectral range(s) will be used in the formula $\lambda / D$ to estimate respectively \emph{s\_fov\_min} and \emph{s\_fov\_max}. \\ In the case of mapping scans or multi-feed/PAF receivers \emph{ s\_fov\_min} and \emph{s\_fov\_max} are derived as the minimum and maximum sizes of the