./guide
molecule.pro

Last modification date:

Wed Sep 28 13:27:09 2016

molecule

procedure molecule, [formula=string(s)], [name=string(s)], [/doprint], [elimit=double], [indices=variable], [/novsource]

Plot the molecular line frequencies for previously detected molecular lines stored in !g.molecules on the currently displayed plot at the appropriate location given the current x-axis.

Note: The display is changed to show frequency as the x-axis if it is not already doing so.

Note: It is assumed that you want them shown at their rest frequency in the frequency reference frame current in use on the plotter adjusted for any source velocity. If the source velocity has already been used to adjust the x-axis display then this routine will plot the molecule lines at their rest frequencies without any offset. Use the /novsource keyword to turn off any consideration of the source velocity - lines are simply plotted at their rest frequencies no matter what the source velocity is or what the displayed x-axis is.

The set of lines to be search can be narrowed by supplying a formula or name. Wildcards are allowed and arrays of formula and names can be supplied.

Only lines with an upper state energy less than or equal to the elimit value (in K) are shown. The default value for this keyword is 50 K.

To show fewer lines use a lower elimit value or select specific lines using the formula or name keywords.

The indices keyword can be used to return the set of indices in the !g.molecules array of molecule_struct structures. This can be used to get access to full information if desired. See moleculeread for a description of the contents of the molecule_struct structure.

The line information was extracted from the Database for Astronomical Spectroscopy - Splatalogue available at www.splatalogue.net specifically tailored for the available spectral line coverage of the GBT. Splatalogue is a fully rationalized and extended compilation of existing spectroscopic resources for use by the astronomical community including, but not limited too, the JPL, CDMS, Lovas/NIST, Frank Lovas' own Spectral Line Atlas of Interstellar Molecules (SLAIM) catalogs.

Splatalogue is maintained at the North American ALMA Science Center with cooperation from the East Asian and European ALMA Regional Centers. The Splatalogue Subsystem Scientist is Anthony Remijan.

For questions, comments, suggestions or concerns about Splatalogue please submit a Helpdesk ticket through the ALMA Science Portal at help.almascience.org.

The text file containing the line information is found at $GBT_IDL_DIR/pro/guide/GBTIDL_RFF.csv

Examples

  ;    All instances of ammonia
  molecule,formula='NH3*'
  ;    Two formulas to match
  molecule,formula=['NH3*','HCCCHO*']
  ;    Alternatively
  molecule,name=['ammonia','2-propynal']
  ; lower the upper state energy cutoff to 20 K
  molecule,elimit=20
  ; get the indices of the species plotted
  molecule,indices=indices
  ; print out their names
  print,!g.molecules[indices].name
 

Uses

moleculeread freq veltovel shiftvel shiftfreq decode_veldef show vline getxrange getyrange getxvoffset getxunits getxoffset getplotterdc textoidl

Version

$Id$

Keywords
formula in, optional string(s) (def. '')	optionally filter the list of molecules to those whose formula matches this string. Wildcards are allowed following the rules of the IDL STRMATCH function. If formula is array of strings, each element is used separately and the final list is the set of all lines with a formula matching any of the strings on that list. If not supplied, the entire list is used. The filter is case insensitive.
name in, optional string(s) (def. '')	optionally filter the list of molecules to those whose name matches this string. Wildcards are allowed following the rules of the IDL STRMATCH function. If name is array of strings, each element is used separately and the final list is the set of all lines with a name matching any of the strings on that list. If not supplied, the entire list is used. The filter is case-insensitive.
doprint in, optional boolean (def. 0)	optionally print the line frequencies. The printed frequencies are the line frequencies in the frame being displayed on the plotter.
elimit in, optional double (def. 50.0)	Only lines with an upper state energy less than or equal to this limit will be plotted. The units are Kelvin. Lowering this limit reduces the number of lines plotted.
indices out, optional variable	The list of indices in !g.molecules of the lines that were plotted. This can be used to get the original information (e.g. rest frequency) of the lines marked on the plot. This has a value of -1 when no lines were plotted.
novsource in, optional boolean	Optionally set this to turn off any consideration of the source velocity when marking the locations of any molecule lines.