pint.models.astrometry.AstrometryEquatorial
- class pint.models.astrometry.AstrometryEquatorial[source]
Bases:
Astrometry
Astrometry in equatorial coordinates.
Parameters supported:
Name / Aliases
Description
Kind
POSEPOCH
Reference epoch for position
d
PX
Parallax
mas
RAJ / RA
Right ascension (J2000)
hourangle
DECJ / DEC
Declination (J2000)
deg
PMRA
Proper motion in RA
mas / yr
PMDEC
Proper motion in DEC
mas / yr
Methods
add_param
(param[, deriv_func, setup])Add a parameter to the Component.
as_ECL
([epoch, ecl])Return pint.models.astrometry.Astrometry object in PulsarEcliptic frame.
as_ICRS
([epoch])Return pint.models.astrometry.Astrometry object in ICRS frame.
barycentric_radio_freq
(toas)Return radio frequencies (MHz) of the toas corrected for Earth motion
change_posepoch
(new_epoch)Change POSEPOCH to a new value and update the position accordingly.
coords_as_ECL
([epoch, ecl])Return the pulsar's ecliptic coordinates as an astropy coordinate object.
coords_as_GAL
([epoch])Return the pulsar's galactic coordinates as an astropy coordinate object.
coords_as_ICRS
([epoch])Return the pulsar's ICRS coordinates as an astropy coordinate object.
d_delay_astrometry_d_DECJ
(toas[, param, ...])Calculate the derivative wrt DECJ
d_delay_astrometry_d_PMDEC
(toas[, param, ...])Calculate the derivative wrt PMDEC
d_delay_astrometry_d_PMRA
(toas[, param, ...])Calculate the derivative wrt PMRA
d_delay_astrometry_d_POSEPOCH
(toas[, param, ...])Calculate the derivative wrt POSEPOCH
d_delay_astrometry_d_PX
(toas[, param, acc_delay])Calculate the derivative wrt PX
d_delay_astrometry_d_RAJ
(toas[, param, ...])Calculate the derivative wrt RAJ
get_d_delay_quantities
(toas)Calculate values needed for many d_delay_d_param functions
get_params_as_ICRS
()get_params_of_type
(param_type)Get all the parameters in timing model for one specific type.
get_prefix_mapping_component
(prefix)Get the index mapping for the prefix parameters.
get_psr_coords
([epoch])Returns pulsar sky coordinates as an astropy ICRS object instance.
is_in_parfile
(para_dict)Check if this subclass included in parfile.
match_param_aliases
(alias)Return the parameter corresponding to this alias.
Print help lines for all available parameters in model.
print_par
([format])- param format:
Parfile output format. PINT outputs the 'tempo', 'tempo2' and 'pint'
register_deriv_funcs
(func, param)Register the derivative function in to the deriv_func dictionaries.
remove_param
(param)Remove a parameter from the Component.
set_special_params
(spcl_params)setup
()Finalize construction loaded values.
solar_system_geometric_delay
(toas[, acc_delay])Returns geometric delay (in sec) due to position of site in solar system.
ssb_to_psb_xyz_ECL
([epoch, ecl])Returns unit vector(s) from SSB to pulsar system barycenter under Ecliptic coordinates.
ssb_to_psb_xyz_ICRS
([epoch])Returns unit vector(s) from SSB to pulsar system barycenter under ICRS.
sun_angle
(toas[, heliocenter, also_distance])Compute the pulsar-observatory-Sun angle.
validate
()Validate the input parameter.
validate_toas
(toas)Check that this model component has TOAs where needed.
xyz_from_radec
(ra, dec)Attributes
Return all the aliases and map to the PINT parameter name.
category
component_types
Return the free parameters in the component.
param_prefixs
register
- print_par(format: str = 'pint') str [source]
- Parameters:
format (str, optional) – Parfile output format. PINT outputs the ‘tempo’, ‘tempo2’ and ‘pint’ format. The defaul format is pint. Actual formatting done elsewhere.
- Returns:
str
- Return type:
formatted line for par file
- barycentric_radio_freq(toas: TOAs) Quantity [source]
Return radio frequencies (MHz) of the toas corrected for Earth motion
- get_psr_coords(epoch: float | Quantity | Time = None) SkyCoord [source]
Returns pulsar sky coordinates as an astropy ICRS object instance.
- Parameters:
epoch (astropy.time.Time or Float, optional) – new epoch for position. If Float, MJD(TDB) is assumed
- Returns:
position – ICRS SkyCoord object optionally with proper motion applied
If epoch (MJD) is specified, proper motion is included to return
the position at the given epoch.
- coords_as_ICRS(epoch: float | Quantity | Time = None) SkyCoord [source]
Return the pulsar’s ICRS coordinates as an astropy coordinate object.
- Parameters:
epoch (float or astropy.time.Time or astropy.units.Quantity, optional) – If float or Quantity, MJD(TDB) is assumed
- Return type:
- coords_as_ECL(epoch: float | Quantity | Time = None, ecl: str = None) SkyCoord [source]
Return the pulsar’s ecliptic coordinates as an astropy coordinate object.
The value used for the obliquity of the ecliptic can be controlled with the ecl keyword, which should be one of the codes listed in ecliptic.dat. If ecl is left unspecified, the global default IERS2010 will be used.
- Parameters:
epoch (float or astropy.time.Time or astropy.units.Quantity, optional) – If float or Quantity, MJD(TDB) is assumed
ecl (str) –
- Return type:
- coords_as_GAL(epoch: float | Quantity | Time = None) SkyCoord [source]
Return the pulsar’s galactic coordinates as an astropy coordinate object.
- Parameters:
epoch (float or astropy.time.Time or astropy.units.Quantity, optional) – If float or Quantity, MJD(TDB) is assumed
- Return type:
- ssb_to_psb_xyz_ICRS(epoch: float | Quantity | Time = None) Quantity [source]
Returns unit vector(s) from SSB to pulsar system barycenter under ICRS.
If epochs (MJD) are given, proper motion is included in the calculation.
- Parameters:
epoch (float or astropy.time.Time or astropy.units.Quantity, optional) – If float or Quantity, MJD(TDB) is assumed
- Returns:
(len(epoch), 3) array of unit vectors
- Return type:
np.ndarray
- d_delay_astrometry_d_RAJ(toas: TOAs, param='', acc_delay=None) Quantity [source]
Calculate the derivative wrt RAJ
For the RAJ and DEC derivatives, use the following approximate model for the pulse delay. (Inner-product between two Cartesian vectors):
de = Earth declination (wrt SSB)
ae = Earth right ascension
dp = pulsar declination
aa = pulsar right ascension
r = distance from SSB to Earh
c = speed of light
delay = r*[cos(de)*cos(dp)*cos(ae-aa)+sin(de)*sin(dp)]/c
- d_delay_astrometry_d_DECJ(toas: TOAs, param='', acc_delay=None) Quantity [source]
Calculate the derivative wrt DECJ
Definitions as in d_delay_d_RAJ
- d_delay_astrometry_d_PMRA(toas: TOAs, param='', acc_delay=None) Quantity [source]
Calculate the derivative wrt PMRA
Definitions as in d_delay_d_RAJ. Now we have a derivative in mas/yr for the pulsar RA
- d_delay_astrometry_d_PMDEC(toas: TOAs, param='', acc_delay=None) Quantity [source]
Calculate the derivative wrt PMDEC
Definitions as in d_delay_d_RAJ. Now we have a derivative in mas/yr for the pulsar DEC
- change_posepoch(new_epoch: float | Quantity | Time)[source]
Change POSEPOCH to a new value and update the position accordingly.
- Parameters:
new_epoch (astropy.time.Time or float or astropy.units.Quantity) – If float or Quantity, MJD(TDB) is assumed. Note that uncertainties are not adjusted. The new POSEPOCH value.
- as_ICRS(epoch: float | Quantity | Time = None) AstrometryEquatorial [source]
Return pint.models.astrometry.Astrometry object in ICRS frame.
- Parameters:
epoch (astropy.time.Time or float or astropy.units.Quantity, optional) – If float or Quantity, MJD(TDB) is assumed. New epoch for position.
- Return type:
- as_ECL(epoch: float | Quantity | Time = None, ecl: str = 'IERS2010') AstrometryEcliptic [source]
Return pint.models.astrometry.Astrometry object in PulsarEcliptic frame.
- Parameters:
epoch (float or astropy.time.Time or astropy.units.Quantity, optional) – If float or Quantity, MJD(TDB) is assumed. New epoch for position.
ecl (str, optional) – Obliquity for PulsarEcliptic frame
- Return type:
- add_param(param, deriv_func=None, setup=False)
Add a parameter to the Component.
The parameter is stored in an attribute on the Component object. Its name is also recorded in a list,
self.params
.- Parameters:
param (pint.models.Parameter) – The parameter to be added.
deriv_func (function) – Derivative function for parameter.
- property aliases_map
Return all the aliases and map to the PINT parameter name.
This property returns a dictionary from the current in timing model parameters’ aliase to the pint defined parameter names. For the aliases of a prefixed parameter, the aliase with an existing prefix index maps to the PINT defined parameter name with the same index. Behind the scenes, the indexed parameter adds the indexed aliase to its aliase list.
- d_delay_astrometry_d_POSEPOCH(toas, param='', acc_delay=None)
Calculate the derivative wrt POSEPOCH
- d_delay_astrometry_d_PX(toas: TOAs, param='', acc_delay=None) Quantity
Calculate the derivative wrt PX
Roughly following Smart, 1977, chapter 9.
px_r: Extra distance to Earth, wrt SSB, from pulsar r_e: Position of earth (vector) wrt SSB u_p: Unit vector from SSB pointing to pulsar t_d: Parallax delay c: Speed of light delta: Parallax
The parallax delay is due to a distance orthogonal to the line of sight to the pulsar from the SSB:
px_r = sqrt( r_e**2 - (r_e.u_p)**2 ),
with delay
t_d = 0.5 * px_r * delta’/ c, and delta = delta’ * px_r / (1 AU)
- property free_params_component
Return the free parameters in the component.
This function collects the non-frozen parameters.
- Return type:
A list of free parameters.
- get_d_delay_quantities(toas: TOAs) dict
Calculate values needed for many d_delay_d_param functions
- get_params_of_type(param_type)
Get all the parameters in timing model for one specific type.
- get_prefix_mapping_component(prefix)
Get the index mapping for the prefix parameters.
- is_in_parfile(para_dict)
Check if this subclass included in parfile.
- Parameters:
para_dict (dictionary) – A dictionary contain all the parameters with values in string from one parfile
- Returns:
Whether the subclass is included in the parfile.
- Return type:
- match_param_aliases(alias)
Return the parameter corresponding to this alias.
- Parameters:
alias (str) – Alias name.
Note
This function only searches the parameter aliases within the current component. If one wants to search the aliases in the scope of TimingModel, please use
TimingModel.match_param_aliase()
.
- param_help()
Print help lines for all available parameters in model.
- register_deriv_funcs(func, param)
Register the derivative function in to the deriv_func dictionaries.
- Parameters:
func (callable) – Calculates the derivative
param (str) – Name of parameter the derivative is with respect to
- remove_param(param)
Remove a parameter from the Component.
- Parameters:
param (str or pint.models.Parameter) – The parameter to remove.
- setup()
Finalize construction loaded values.
- solar_system_geometric_delay(toas: TOAs, acc_delay=None) Quantity
Returns geometric delay (in sec) due to position of site in solar system. This includes Roemer delay and parallax.
NOTE: currently assumes XYZ location of TOA relative to SSB is available as 3-vector toa.xyz, in units of light-seconds.
- ssb_to_psb_xyz_ECL(epoch: float | Quantity | Time = None, ecl: str = None) Quantity
Returns unit vector(s) from SSB to pulsar system barycenter under Ecliptic coordinates.
If epochs (MJD) are given, proper motion is included in the calculation.
- Parameters:
epoch (float or astropy.time.Time or astropy.units.Quantity, optional) – If float or Quantity, MJD(TDB) is assumed
ecl (str, optional) – Obliquity (IERS2010 by default)
- Returns:
(len(epoch), 3) array of unit vectors
- Return type:
np.ndarray
- sun_angle(toas: TOAs, heliocenter: bool = True, also_distance: bool = False) ndarray
Compute the pulsar-observatory-Sun angle.
This is the angle between the center of the Sun and the direction to the pulsar, as seen from the observatory (for each TOA).
This angle takes into account the motion of the Sun around the solar system barycenter.
- Parameters:
toas (
pint.toa.TOAs
) – The pulse arrival times at which to evaluate the sun angle.heliocenter (bool) – Whether to use the Sun’s actual position (the heliocenter) or the solar system barycenter. The latter may be useful for comparison with other software.
also_distance (bool) – If True, also return the observatory-Sun distance as a Quantity
- Returns:
The angle in radians
- Return type:
array
- validate_toas(toas)
Check that this model component has TOAs where needed.