NAME

nihaloem - estimate Galactic Halo & Local Hot Bubble emission

USAGE

nihaloem lon lat coordsys

DESCRIPTION

The nihaloem task estimates the emission measures due to the galactic halo and local hot bubble, for use with the NICER SCORPEON model.

The Galactic Halo emission measure is calculated by performing a raytrace through the density model of Kaaret et al. 2019.

The Local Hot Bubble (LHB) is estimated very crudely by consulting contours derived from Liu et al. 2017. Please note that there are only a few contour levels so this estimate should be considered extremely crude.

Please see the help for niscorpeon for more information about these models.

The user inputs either R.A. and Dec. (with coordsys='R') or galactic longitude and latitude (with coordsys='G'). The result is printed to the screen and also saved in the parameter file.

Please note that the task does create some temporary files. These files are stored in the directory designated by the scratchdir parameter, which is the current working directory by default.

PARAMETERS

lon [real]
Input Right Ascenscion (J2000) or Galactic Longitude in degrees.
lat [real]
Input Declination (J2000) or Galactic Latitude in degrees.
coordsys [string]
Coordinate system of inputs, either "R" for J2000 equatorial (RA/Dec) or "G" for galactic.
(haloem=0.0) [real]
Upon return, the estimated galactic halo emission measure in units of cm^-6 pc.
(lhbem=0.0) [real]
Upon return, the estimated local hot bubble emission measure in units of cm^-6 pc.
(scratchdir=".") [string]
Path to directory where scratch files may be stored. The default of scratchdir="." means store scratch files in the current working directory.
(cleanup="YES") [boolean]
If yes, then clean up temporary files. If no, temporary files remain. This is typically for debugging.
(clobber = NO) [boolean]
If the output file already exists, then setting "clobber = yes" will cause it to be overwritten.
(chatter = 2) [integer, 0 - 5]
Controls the amount of informative text written to standard output. Setting chatter = 4 or higher will produce detailed diagnostic output; chatter = 1 prints out a basic diagnostic message. The default is to produce a brief summary on output.
(history = YES) [boolean]
If history = YES, then a set of HISTORY keywords will be written to the header of the specified HDU in the output file to record the value of all the nihaloem task parameters that were used to produce the output file.

EXAMPLES

Run nihaloem for (RA,Dec) = (123.45,-67.890).


   nihaloem 123.45 -67.890 R

and the result is,
nihaloem 1.0
--------------------------------------------------------
     Halo EM = 2.6397e-02 cm^-6 pc
     LHB  EM = 2.2000e-03 cm^-6 pc
--------------------------------------------------------
DONE

SEE ALSO

niscorpeon

LAST MODIFIED

Aug 2022