The following following JWST instrument/mode combinations are currently implemented, working, and part of the nightly regression tests:
-
miri:- imaging
- mrs
- coronagraphy
- lrsslit
- lrsslitless
-
nircam:- sw_imaging
- lw_imaging
- ssgrism
- wfgrism
- coronagraphy
-
nirspec:- ifu
- msa
- fixed_slit
-
niriss:- imaging
- soss
- ami
- wfss
The following HST instrument/mode combination is not yet fully implemented, but will be available for engine testing and validation:
wfc3:- imaging
The following WFIRST instrument/mode combination is now implemented with very notional reference data:
wfirstimager:- imaging
- ifu
The engine input api is a dict. At the top level of the dict, there are:
background: string for notional background lookup, or see below
configuration: dict: camera/telescope configuration
scene: list: list of sources
strategy: dict: strategy configuration
calculation: dict: test interface
fake_exception: test interface
error, server_test: reserved by server
NOTE - keep all of the following in synch with: pandeia/engine/helpers/schema
As of now, the engine requires the following information to perform a calculation:
scene: list (no default) This is a list of Sources. Each Source is described by a dict with the following keys:
position: dict
Source position parameters described by the following keys:
x_offset: float (default 0.0)
Detector plane X offset from FOV center in arcseconds. Positive to the right.
y_offset: float (default 0.0)
Detector plane Y offset from FOV center in arcseconds. Positive is up.
orientation: float (default 0.0)
Detector plane orientation in degrees. Positive is in direction of +X.
(e.g. orientation=90 is UP, and orientation=-90 is DOWN)
shape: dict
Source shape parameters described by the following keys:
geometry: string (default "point")
Supported geometries are "point", "gaussian2d", "flat", and "sersic". Required
additional source shape parameters are contingent on this parameter:
"point" requires no additional parameters.
"gaussian2d", "flat", and "sersic" all require these parameters:
major: float (default 0.1)
Semi-major axis in arcseconds. For "flat" this sets the size, for "gaussian2d"
this sets the sigma, and for "sersic" this sets a scale length where
I(r) = I(0)/e.
minor: float (default 0.1)
Semi-minor axis in arcseconds
"sersic" requires one additional parameter:
sersic_index: float (default 1.0)
Power law index that sets the shape of a sersic profile.
sersic_index = 1.0 --> exponential
sersic_index = 0.5 --> gaussian
sersic_index = 4.0 --> de Vaucouleurs
spectrum: dict
Source spectral parameters described by the following keys:
redshift: float (default 0.0)
Redshift to apply to the continuum. Since lines are added with physical units for their strength,
they are added to the spectrum after normalization and redshift.
extinction: dict
Defines how the spectrum is reddened by interstellar dust
law: string
Extinction law to use. Supported laws are
* ``mw_rv_31`` - WD01 Milky Way curve for an R_V value of 3.1 (default)
* ``mw_rv_40`` - WD01 Milky Way curve for an R_V value of 4.0
* ``mw_rv_55`` - WD01 Milky Way curve for an R_V value of 5.5
* ``hd210121`` - WD01 Extinction curve for high-latitude molecular cloud hd210121 with C/H = b_C = 40 ppm
in log-normal size dists
* ``lmc_avg`` - WD01 Average extinction curve for the LMC with C/H = b_C = 20 ppm in log-normal size dists
* ``lmc_2`` - WD01 LMC extinction curve with C/H = b_C = 10 ppm in log-normal size dists (30 Dor region)
* ``smc_bar`` - WD01 Extinction curve in SMC bar with C/H = b_C = 0 ppm in log-normal size dists
* ``chapman09`` - Chapman et al. (2009) mid-IR extinction curve derived from three molecular clouds:
Ophiuchus, Perseus, and Serpens
value: float
Level of extinction in units of unit
unit: string
Units of extinction. Allowed values are ``nh`` for hydrogen column density (cm^-2) and "mag" for magnitudes
of extinction in specified bandpass, ext_bandpass
bandpass: string
Bandpass to which extinction is normalized to if unit="mag". Allowed values are v, j, h, and k.
normalization: dict
Defines how the spectrum is to be scaled.
type: string
Method of normalization to perform. Supported methods are
* ``at_lambda`` - Specify norm_flux in fluxunit at a specfic wavelength, norm_wave
* ``hst`` - Specify a bandpass in the form of an "obsmode" string to pass along to pysynphot along with fluxunit and norm_flux
* ``jwst`` - Specify a bandpass as an instrument configuration in the form of a comma-separated string <instrument>,<mode>,<filter> along with fluxunit and norm_flux
* ``photsys`` - Specify bandpass in the form of a comma-separated string <photsys>,<filter>
* ``none`` - Do not normalize spectrum. Only valid for a spectrum type of 'input'.
norm_wave: float
Reference wavelength in 'norm_waveunit' at which spectrum will be scaled for type 'at_lambda'.
Ignored for other normalization types.
norm_flux: float
Reference flux in 'norm_fluxunit' to which spectrum will be scaled.
norm_fluxunit: string
Specify the flux units in which the normalization should occur.
Supports flam, fnu, vegamag, abmag, mjy, ujy, njy, jy
norm_waveunit: string
Specify the wavelength units used in normalization
bandpass: string
Specifies the key used to obtain the normalization bandpass for
types 'hst', 'jwst', and 'photsys'.
sed: dict
Defines the spectral energy distribution of the spectrum.
sed_type: string
Type of the spectral energy distribution. Each type requires its own set
of parameters. The analytic sed_type's (none, flat, powerlaw, flat) all
require 'wmin', 'wmax', and 'sampling' to define the range and wavelength
sampling over which the model spectrum is calculated. However, they are only
available in the API for testing purposes and should not be configured via
the UI.
**no_continuum** - No continuum, specifically Flux = 0.0 over specified range [wmin, wmax]
wmin: float (default 0.5)
Minimum wavelength in microns
wmax: float (default 30.0)
Maximum wavelength in microns
sampling: int (default 200)
Sets the logarithmic wavelength sampling of the model spectrum
**flat** - Flat spectrum in specified units calculated over specified range [wmin, wmax]
wmin: float (default 0.5)
Minimum wavelength in microns
wmax: float (default 30.0)
Maximum wavelength in microns
sampling: int (default 200)
Sets the logarithmic wavelength sampling of the model spectrum
unit: string
Units of spectrum, either 'fnu' or 'flam'
**powerlaw** - Powerlaw spectrum where F ~ lambda ^ index calculated over range [wmin, wmax]
wmin: float (default 0.5)
Minimum wavelength in microns
wmax: float (default 30.0)
Maximum wavelength in microns
sampling: int (default 200)
Sets the logarithmic wavelength sampling of the model spectrum
unit: string
Units of spectrum, either 'fnu' or 'flam'
index: float
Exponent of the power law
**blackbody** - Blackbody spectrym calculated over range [wmin, wmax]
wmin: float (default 0.5)
Minimum wavelength in microns
wmax: float (default 30.0)
Maximum wavelength in microns
sampling: int (default 200)
Sets the logarithmic wavelength sampling of the model spectrum
temp: float
Temperature of the blackbody
**phoenix** - Parameterized stellar atmosphere models calculated by the Phoenix group
key: string
In webapp mode, a key is used to look up a predefined set of parameters. If not
in webapp mode and if key is not provided, model parameters can be passed directly:
teff: float
Effective temperature. Allowed range is 2000 K to 70000 K
log_g: float
Surface gravity in log10(cgs) units. Allowed range is 0.0 to 5.5.
metallicity: float
Metallicity in units of log10(solar metallicity). Allowed range is -4.0 to 0.5.
**hst_calspec** - HST standard star spectra
key: string
Key used to look up which spectrum load.
**galaxies** - Integrated spectra of galaxies from Brown et al. (2014)
key: string
Key used to look up which spectrum load.
**input** - spectrum provided via input arrays
spectrum: list-like or numpy.ndarray
The 0th index is taken to be wavelength in units of 'mJy'.
The 1st index is taken to be the flux in units of 'microns'.
lines: list (default [])
List of line definitions. Each definition is a dict with keys:
name: string (default 'no name')
Name of line (e.g. 'Hydrogen Alpha')
center: float (default 5.2)
Wavelength at line center in w_unit
strength: float (default 1.0e-14)
Strength of line in erg/cm^2/s for emission or
optical depth for absorption
profile: string
Line profile type:
* gaussian *default*
* voigt NOT YET IMPLEMENTED
emission_or_absorption: string
Line type:
* emission *default*
* absorption
A profile type of **gaussian** requires one additional parameter:
width: float (default 200.0)
Full-width half-max of line in km/s
When implemented, profile type of **voigt** will require two additional parameters:
gaussian_fwhm: float (default 200.0)
Full-width half-max of the gaussian core of the line in units of km/s
lorentzian_fwhm: float (default 500.0)
Full-width half-max of the lorentzian wings of the line in units of km/s
background: string (default 'medium') or list-like or numpy.ndarray Possible string values are: none, low, medium, and high. String values trigger the use of a notional background model. If a background spectrum is provided, it is assumed that the 0th index is the wavelength in microns and the 1st index is the background surface brightness in MJy/sr.
calculation: dict Set of boolean parameters to toggle the inclusion of different effects and noise parameters in a calculation. This section is optional and largely for testing purposes. Do not expect to support this in the UI.
noise: dict
Noise components
darkcurrent: bool
Dark current
crs: bool
Cosmic rays
rn_correlation: bool
Correlated read noise
ffnoise: bool
Flat-field noise
readnoise: bool
Detector read-out noise
effects: dict
Effects that can affect the noise or detector response or both
ipc: bool
Inter-pixel capacitance
saturation: bool
Pixel saturation
background: bool
Include background in calculation or not
configuration: dict This configuration for the instrument using the following keys:
instrument: dict
The instrument configuration parameters
instrument: string
for JWST:
* miri
* nircam
* nirspec
* niriss
for HST:
* wfc3 (NOT IMPLEMENTED)
for WFIRST:
* wfirstimager
* wfirstifu
mode: string
valid modes:
* imaging
* sw_imaging
* lw_imaging
* msa
* mrs
* soss
* ifu
* wfss
* ssgrism
* wfgrism
* lrsslit
* lrsslitless
* fixed_slit
* ami
* coronagraphy
filter: string
(e.g. f070w)
disperser: string
(e.g. g235h)
aperture: string
(e.g. a200)
shutter_location: string (only valid for NIRSpec MSA mode)
Identifier string for slitlet position to use for MSA calculation
slitlet_shape: list-like (only valid for NIRSpec MSA mode)
List of 2-element offsets describing set of shutters to be open. Offsets are from scene center
in units of shutter spacing.
detector: dict
Exposure configuration parameters.
subarray: string
full, 64x64, etc.; Instrument-dependent
readmode: string
Instrument-dependent
ngroup: int
Number of groups
nint: int
Number of integrations
nexp: int
Number of exposures
dynamic_scene: boolean
Toggle whether to allow the size of the scene to expand dynamically to include all configured sources.
scene_size: float
Default size of the scene in arcseconds. Used if dynamic_scene is True.
max_scene_size: float
Maximum allowable scene_size in arcseconds.
strategy: dict Configuration parameters for observing strategy.
method: string
Instrument and mode dependent. Currently supported methods are:
* imagingapphot
* specapphot
* coronagraphy
* ifuapphot
* ifunodinscene
* ifunodoffscene
* msafullapphot
* soss
Planned methods that are not yet implemented include:
imagingoptphot, specoptphot, speclinephot
units: string (default: "arcsec")
Angular units used by the strategy
target_source: string
Sent by the UI client, but currently unused by the engine
target_type: string
Sent by the UI client, but currently unused by the engine
The rest of the parameters will be method dependent. The parameters required
for **imagingapphot**, **specapphot**, and **ifuapphot** are:
aperture_size: float
Size of extraction aperture in "units"
sky_annulus: list-like of format (float, float)
The inner and outer radii in "units" of sky region used for background subtraction
target_xy: list-like of format (float, float)
X and Y center position of the aperture and sky annulus.
The parameters required for **ifunodinscene** and **ifunodoffscene** are:
aperture_size: float
Size of extraction aperture in "units"
target_xy: list-like of format (float, float)
X and Y center position of the aperture and sky annulus.
dithers: list of dicts with format {'x': <float>, 'y': <float>}
Dither positions given in "units" from center of the Scene.
The parameters required for **msafullapphot** are:
shutter_offset: list-like of format (float, float)
Offset of shutter pattern from center of scene in "units"
dithers: list of dicts
Dither positions and MSA shutter configuration with the following format:
x: float
X position of the central shutter
y: float
Y position of the central shutter
on_source: list of bool
List of booleans denoting whether a shutter should be treated as source or sky.
Must be of same length as "slitlet_shape" specified in the instrument configuration.
The parameters required for **soss** are:
background_subtraction: boolean
Toggle whether background subtraction is performed or not.
order: int
Specify which order to extract. Can be 1 or 2 with support for 3 forthcoming.
The parameters required for **coronagraphy** are:
target_xy: two-element list-like (float, float)
Position of extraction aperture
aperture_size: float
Radius of extraction aperture in 'units'
sky_annulus: two-element list-like (float, float)
Inner and outer radii of sky background estimation region
contrast_azimuth: float
Azimuth at which to calculate contrast curve
pointing_error: two-element list-like (float, float)
Amount to shift occulted source to emulate imperfect pointing
delta_opd: float
Change in system OPD
scene_rotation: float
Rotation angle to apply to scene
psf_subtraction_source: Source dict in engine API format
Definition of source to use for PSF subtraction
psf_subtraction_xy: two-element list-like (float, float)
Offset to apply to psf_subtraction_source
unocculted_xy: two-element list-like (float, float)
Offset to apply to source to measure contrast between occulted and unocculted observation
The parameters required for the planned methods will be defined as the methods
are implemented.
fake_exception: list of strings If present, this list is searched for control terms that cause perform_calculation to raise exceptions for testing purposes. Currently recognized strings are:
'pyetc':
raise PyetcException
'exception':
raise Exception
Other strings may be added later to add exceptions or modify
the details of the exception objects raised.