# Source code for xga.sourcetools.temperature

```
# This code is a part of X-ray: Generate and Analyse (XGA), a module designed for the XMM Cluster Survey (XCS).
# Last modified by David J Turner (turne540@msu.edu) 20/02/2023, 14:04. Copyright (c) The Contributors
from typing import Tuple, Union, List
from warnings import warn
import numpy as np
from astropy.units import Quantity
from .deproj import shell_ann_vol_intersect
from .. import NUM_CORES, ABUND_TABLES
from ..exceptions import NoProductAvailableError
from ..imagetools.misc import pix_deg_scale
from ..imagetools.profile import annular_mask
from ..products.profile import GasTemperature3D
from ..samples import BaseSample, ClusterSample
from ..sas import region_setup
from ..sources import BaseSource, GalaxyCluster
from ..xspec.fit import single_temp_apec_profile
ALLOWED_ANN_METHODS = ['min_snr', 'min_cnt']
def _ann_bins_setup(source: BaseSource, outer_rad: Quantity, min_width: Quantity, lo_en: Quantity, hi_en: Quantity,
obs_id: str = None, inst: str = None, psf_corr: bool = False, psf_model: str = "ELLBETA",
psf_bins: int = 4, psf_algo: str = "rl", psf_iter: int = 15):
"""
This method just sets up radii, masks, etc. for annular binning functions in this file. The operations in
this function are shared by multiple other binning functions, hence they have been put in a function of their
own to minimise duplication.
:param BaseSource source: The source object to generate annuli for.
:param Quantity outer_rad: The outermost radius of the source region we will generate annuli within.
:param Quantity min_width: The minimum allowable width of the annuli. This can be set to try and avoid
PSF effects.
:param Quantity lo_en: The lower energy bound of the ratemap to use for the signal to noise calculations.
:param Quantity hi_en: The upper energy bound of the ratemap to use for the signal to noise calculations.
:param str obs_id: An ObsID of a specific ratemap to use for the SNR calculations. Default is None, which
means the combined ratemap will be used. Please note that inst must also be set to use this option.
:param str inst: The instrument of a specific ratemap to use for the SNR calculations. Default is None, which
means the combined ratemap will be used.
:param bool psf_corr: Sets whether you wish to use a PSF corrected ratemap or not.
:param str psf_model: If the ratemap you want to use is PSF corrected, this is the PSF model used.
:param int psf_bins: If the ratemap you want to use is PSF corrected, this is the number of PSFs per
side in the PSF grid.
:param str psf_algo: If the ratemap you want to use is PSF corrected, this is the algorithm used.
:param int psf_iter: If the ratemap you want to use is PSF corrected, this is the number of iterations.
:return: The various variables that this function sets up
:rtype:
"""
# Parsing the ObsID and instrument options, see if they want to use a specific ratemap
if all([obs_id is None, inst is None]):
# Here the user hasn't set ObsID or instrument, so we use the combined data
rt = source.get_combined_ratemaps(lo_en, hi_en, psf_corr, psf_model, psf_bins, psf_algo, psf_iter)
interloper_mask = source.get_interloper_mask()
elif all([obs_id is not None, inst is not None]):
# Both ObsID and instrument have been set by the user
rt = source.get_ratemaps(obs_id, inst, lo_en, hi_en, psf_corr, psf_model, psf_bins, psf_algo, psf_iter)
interloper_mask = source.get_interloper_mask(obs_id)
# Just making sure our relevant distances are in the same units, so that we can convert to pixels
outer_rad = source.convert_radius(outer_rad, 'deg')
min_width = source.convert_radius(min_width, 'deg')
# Using the ratemap to get a conversion factor from pixels to degrees, though we will use it
# the other way around
pix_to_deg = pix_deg_scale(source.default_coord, rt.radec_wcs)
# Making sure to go up to the whole number, pixels have to be integer of course, and I think it's
# better to err on the side of caution here and make things slightly wider than requested
outer_rad = int(np.ceil(outer_rad / pix_to_deg).value)
min_width = int(np.ceil(min_width / pix_to_deg).value)
# The maximum possible number of annuli, based on the input outer radius and minimum width
# We have already made sure that the outer radius and minimum width allowed are integers by using
# np.ceil, so we know max_ann is going to be a whole number of annuli
max_ann = int(outer_rad / min_width)
# These are the initial bins, with imposed minimum width, I have to add one to max_ann because linspace wants the
# total number of values to generate, and while there are max_ann annuli, there are max_ann+1 radial boundaries
init_rads = np.linspace(0, outer_rad, max_ann + 1).astype(int)
# Converts the source's default analysis coordinates to pixels
pix_centre = rt.coord_conv(source.default_coord, 'pix')
# Sets up a mask to correct for interlopers and weird edge effects
corr_mask = interloper_mask * rt.edge_mask
# Setting up our own background region
back_inn_rad = np.array([np.ceil(source.background_radius_factors[0] * outer_rad)]).astype(int)
back_out_rad = np.array([np.ceil(source.background_radius_factors[1] * outer_rad)]).astype(int)
# Using my annular mask function to make a nice background region, which will be corrected for instrumental
# stuff and interlopers in a second
back_mask = annular_mask(pix_centre, back_inn_rad, back_out_rad, rt.shape) * corr_mask
# Generates the requested annular masks, making sure to apply the correcting mask
ann_masks = annular_mask(pix_centre, init_rads[:-1], init_rads[1:], rt.shape) * corr_mask[..., None]
cur_rads = init_rads.copy()
return rt, cur_rads, max_ann, ann_masks, back_mask, pix_centre, corr_mask, pix_to_deg
def _snr_bins(source: BaseSource, outer_rad: Quantity, min_snr: float, min_width: Quantity, lo_en: Quantity,
hi_en: Quantity, obs_id: str = None, inst: str = None, psf_corr: bool = False, psf_model: str = "ELLBETA",
psf_bins: int = 4, psf_algo: str = "rl", psf_iter: int = 15,
allow_negative: bool = False, exp_corr: bool = True) -> Tuple[Quantity, np.ndarray, int]:
"""
An internal function that will find the radii required to create annuli with a certain minimum signal to noise
and minimum annulus width.
:param BaseSource source: The source object to generate annuli for.
:param Quantity outer_rad: The outermost radius of the source region we will generate annuli within.
:param float min_snr: The minimum signal to noise which is allowable in a given annulus.
:param Quantity min_width: The minimum allowable width of the annuli. This can be set to try and avoid
PSF effects.
:param Quantity lo_en: The lower energy bound of the ratemap to use for the signal to noise calculations.
:param Quantity hi_en: The upper energy bound of the ratemap to use for the signal to noise calculations.
:param str obs_id: An ObsID of a specific ratemap to use for the SNR calculations. Default is None, which
means the combined ratemap will be used. Please note that inst must also be set to use this option.
:param str inst: The instrument of a specific ratemap to use for the SNR calculations. Default is None, which
means the combined ratemap will be used.
:param bool psf_corr: Sets whether you wish to use a PSF corrected ratemap or not.
:param str psf_model: If the ratemap you want to use is PSF corrected, this is the PSF model used.
:param int psf_bins: If the ratemap you want to use is PSF corrected, this is the number of PSFs per
side in the PSF grid.
:param str psf_algo: If the ratemap you want to use is PSF corrected, this is the algorithm used.
:param int psf_iter: If the ratemap you want to use is PSF corrected, this is the number of iterations.
:param bool allow_negative: Should pixels in the background subtracted count map be allowed to go below
zero, which results in a lower signal to noise (and can result in a negative signal to noise).
:param bool exp_corr: Should signal to noises be measured with exposure time correction, default is True. I
recommend that this be true for combined observations, as exposure time could change quite dramatically
across the combined product.
:return: The radii of the requested annuli, the final snr values, and the original maximum number
based on min_width.
:rtype: Tuple[Quantity, np.ndarray, int]
"""
# This calls a function that just sets things up for this (and other annular binning) function
rt, cur_rads, max_ann, ann_masks, back_mask, pix_centre, corr_mask, \
pix_to_deg = _ann_bins_setup(source, outer_rad, min_width, lo_en, hi_en, obs_id, inst, psf_corr, psf_model,
psf_bins, psf_algo, psf_iter)
if max_ann > 4:
# This will be modified by the loop until it describes annuli which all have an acceptable signal to noise
acceptable = False
else:
# If there are already 4 or less annuli present then we don't do the reduction while loop, and just take it
# as they are, while also issuing a warning
acceptable = True
warn("The min_width combined with the outer radius of the source means that there are only {} initial"
" annuli, normally four is the minimum number I will allow, so I will do no re-binning.".format(max_ann))
cur_num_ann = ann_masks.shape[2]
snrs = []
for i in range(cur_num_ann):
# We're calling the signal to noise calculation method of the ratemap for all of our annuli
snrs.append(rt.signal_to_noise(ann_masks[:, :, i], back_mask, exp_corr, allow_negative))
# Becomes a numpy array because they're nicer to work with
snrs = np.array(snrs)
while not acceptable:
# How many annuli are there at this point in the loop?
cur_num_ann = ann_masks.shape[2]
# Just a list for the snrs to live in
snrs = []
for i in range(cur_num_ann):
# We're calling the signal to noise calculation method of the ratemap for all of our annuli
snrs.append(rt.signal_to_noise(ann_masks[:, :, i], back_mask, exp_corr, allow_negative))
# Becomes a numpy array because they're nicer to work with
snrs = np.array(snrs)
# We find any indices of the array (== annuli) where the signal to noise is not above our minimum
bad_snrs = np.where(snrs < min_snr)[0]
# If there are no annuli below our signal to noise threshold then all is good and joyous and we accept
# the current radii
if len(bad_snrs) == 0:
acceptable = True
# We work from the outside of the bad list inwards, and if the outermost bad bin is the one right on the
# end of the SNR profile, then we merge that leftwards into the N-1th annuli
elif len(bad_snrs) != 0 and bad_snrs[-1] == cur_num_ann - 1:
cur_rads = np.delete(cur_rads, -2)
ann_masks = annular_mask(pix_centre, cur_rads[:-1], cur_rads[1:], rt.shape) * corr_mask[..., None]
# Otherwise if the outermost bad annulus is NOT right at the end of the profile, we merge to the right
else:
cur_rads = np.delete(cur_rads, bad_snrs[-1])
ann_masks = annular_mask(pix_centre, cur_rads[:-1], cur_rads[1:], rt.shape) * corr_mask[..., None]
if ann_masks.shape[2] == 4 and not acceptable:
warn("The requested annuli for {s} cannot be created, the data quality is too low. As such a set "
"of four annuli will be returned".format(s=source.name))
break
# Now of course, pixels must become a more useful unit again
final_rads = (Quantity(cur_rads, 'pix') * pix_to_deg).to("arcsec")
return final_rads, snrs, max_ann
def _cnt_bins(source: BaseSource, outer_rad: Quantity, min_cnt: Union[int, Quantity],
min_width: Quantity, lo_en: Quantity, hi_en: Quantity, obs_id: str = None, inst: str = None,
psf_corr: bool = False, psf_model: str = "ELLBETA", psf_bins: int = 4, psf_algo: str = "rl",
psf_iter: int = 15) -> Tuple[Quantity, Quantity, int]:
"""
An internal function that will find the radii required to create annuli with a certain minimum number of counts
and minimum annulus width.
:param BaseSource source: The source object to generate annuli for.
:param Quantity outer_rad: The outermost radius of the source region we will generate annuli within.
:param float min_cnt: The minimum number of counts which are allowable in a given annulus.
:param Quantity min_width: The minimum allowable width of the annuli. This can be set to try and avoid
PSF effects.
:param Quantity lo_en: The lower energy bound of the ratemap to use for the background subtracted count
calculations.
:param Quantity hi_en: The upper energy bound of the ratemap to use for the background subtracted count
calculations.
:param str obs_id: An ObsID of a specific ratemap to use for the background subtracted count
calculations. Default is None, which means the combined ratemap will be used. Please note that inst
must also be set to use this option.
:param str inst: The instrument of a specific ratemap to use for the background subtracted count
calculations. Default is None, which means the combined ratemap will be used.
:param bool psf_corr: Sets whether you wish to use a PSF corrected ratemap or not.
:param str psf_model: If the ratemap you want to use is PSF corrected, this is the PSF model used.
:param int psf_bins: If the ratemap you want to use is PSF corrected, this is the number of PSFs per
side in the PSF grid.
:param str psf_algo: If the ratemap you want to use is PSF corrected, this is the algorithm used.
:param int psf_iter: If the ratemap you want to use is PSF corrected, this is the number of iterations.
:return: The radii of the requested annuli, the final count values, and the original maximum number
based on min_width.
:rtype: Tuple[Quantity, Quantity, int]
"""
# This just makes sure that the min_cnt variable is the astropy quantity that we expect it to be, otherwise
# some of the comparisons made between it and the values returned by background_subtracted_counts will fail
if type(min_cnt) == int:
min_cnt = Quantity(min_cnt, 'ct')
elif (type(min_cnt) == Quantity and not min_cnt.unit.is_equivalent('ct')) or not type(min_cnt) == Quantity:
raise TypeError("The min_cnt argument must be either an integer, or an astropy Quantity in units of 'ct'.")
# Run the setup function for these functions that create different annular bins
rt, cur_rads, max_ann, ann_masks, back_mask, pix_centre, corr_mask, \
pix_to_deg = _ann_bins_setup(source, outer_rad, min_width, lo_en, hi_en, obs_id, inst, psf_corr, psf_model,
psf_bins, psf_algo, psf_iter)
if max_ann > 4:
# This will be modified by the loop until it describes annuli which all have an acceptable signal to noise
acceptable = False
else:
# If there are already 4 or less annuli present then we don't do the reduction while loop, and just take it
# as they are, while also issuing a warning
acceptable = True
warn("The min_width combined with the outer radius of the source means that there are only {} initial"
" annuli, normally four is the minimum number I will allow, so I will do no re-binning.".format(max_ann))
cur_num_ann = ann_masks.shape[2]
cnts = []
for i in range(cur_num_ann):
# We're calling the background subtracted counts calculation method of the ratemap for all of our annuli
cnts.append(rt.background_subtracted_counts(ann_masks[:, :, i], back_mask))
# Becomes an astropy quantity (and so behaves like a numpy array) because they're nicer to work with
cnts = Quantity(cnts)
while not acceptable:
# How many annuli are there at this point in the loop?
cur_num_ann = ann_masks.shape[2]
# Just a list for the counts to live in
cnts = []
for i in range(cur_num_ann):
# We're calling the background subtracted count calculation method of the ratemap
# for all of our annuli
cnts.append(rt.background_subtracted_counts(ann_masks[:, :, i], back_mask))
# Becomes an astropy Quantity (behaves like a numpy array) because they're nicer to work with
cnts = Quantity(cnts)
# We find any indices of the array (== annuli) where the counts are not above our minimum
bad_cnts = np.where(cnts < min_cnt)[0]
# If there are no annuli below our count threshold then all is good and joyous, and we
# accept the current radii
if len(bad_cnts) == 0:
acceptable = True
# We work from the outside of the bad list inwards, and if the outermost bad bin is the one right on the
# end of the count profile, then we merge that leftwards into the N-1th annuli
elif len(bad_cnts) != 0 and bad_cnts[-1] == cur_num_ann - 1:
cur_rads = np.delete(cur_rads, -2)
ann_masks = annular_mask(pix_centre, cur_rads[:-1], cur_rads[1:], rt.shape) * corr_mask[..., None]
# Otherwise if the outermost bad annulus is NOT right at the end of the profile, we merge to the right
else:
cur_rads = np.delete(cur_rads, bad_cnts[-1])
ann_masks = annular_mask(pix_centre, cur_rads[:-1], cur_rads[1:], rt.shape) * corr_mask[..., None]
if ann_masks.shape[2] == 4 and not acceptable:
warn("The requested annuli for {s} cannot be created, the data quality is too low. As such a set "
"of four annuli will be returned".format(s=source.name))
break
# Now of course, pixels must become a more useful unit again
final_rads = (Quantity(cur_rads, 'pix') * pix_to_deg).to("arcsec")
return final_rads, cnts, max_ann
[docs]def min_snr_proj_temp_prof(sources: Union[GalaxyCluster, ClusterSample], outer_radii: Union[Quantity, List[Quantity]],
min_snr: float = 20, min_width: Quantity = Quantity(20, 'arcsec'), use_combined: bool = True,
use_worst: bool = False, lo_en: Quantity = Quantity(0.5, 'keV'),
hi_en: Quantity = Quantity(2, 'keV'), psf_corr: bool = False, psf_model: str = "ELLBETA",
psf_bins: int = 4, psf_algo: str = "rl", psf_iter: int = 15, allow_negative: bool = False,
exp_corr: bool = True, group_spec: bool = True, min_counts: int = 5, min_sn: float = None,
over_sample: float = None, one_rmf: bool = True, freeze_met: bool = True,
abund_table: str = "angr", temp_lo_en: Quantity = Quantity(0.3, 'keV'),
temp_hi_en: Quantity = Quantity(7.9, 'keV'), num_cores: int = NUM_CORES) -> List[Quantity]:
"""
This is a convenience function that allows you to quickly and easily start measuring projected
temperature profiles of galaxy clusters, deciding on the annular bins using signal to noise measurements
from photometric products. This function calls single_temp_apec_profile, but doesn't expose all of the more
in depth variables, so if you want more control then use single_temp_apec_profile directly. The projected
temperature profiles which are generated are added to their source's storage structure.
:param GalaxyCluster/ClusterSample sources: An individual or sample of sources to measure projected
temperature profiles for.
:param str/Quantity outer_radii: The name or value of the outer radius to use for the generation of
the spectra (for instance 'r200' would be acceptable for a GalaxyCluster, or Quantity(1000, 'kpc')). If
'region' is chosen (to use the regions in region files), then any inner radius will be ignored. If you are
generating for multiple sources then you can also pass a Quantity with one entry per source.
:param float min_snr: The minimum signal to noise which is allowable in a given annulus.
:param Quantity min_width: The minimum allowable width of an annulus. The default is set to 20 arcseconds to try
and avoid PSF effects.
:param bool use_combined: If True then the combined RateMap will be used for signal to noise annulus
calculations, this is overridden by use_worst.
:param bool use_worst: If True then the worst observation of the cluster (ranked by global signal to noise) will
be used for signal to noise annulus calculations.
:param Quantity lo_en: The lower energy bound of the ratemap to use for the signal to noise calculations.
:param Quantity hi_en: The upper energy bound of the ratemap to use for the signal to noise calculations.
:param bool psf_corr: Sets whether you wish to use a PSF corrected ratemap or not.
:param str psf_model: If the ratemap you want to use is PSF corrected, this is the PSF model used.
:param int psf_bins: If the ratemap you want to use is PSF corrected, this is the number of PSFs per
side in the PSF grid.
:param str psf_algo: If the ratemap you want to use is PSF corrected, this is the algorithm used.
:param int psf_iter: If the ratemap you want to use is PSF corrected, this is the number of iterations.
:param bool allow_negative: Should pixels in the background subtracted count map be allowed to go below
zero, which results in a lower signal to noise (and can result in a negative signal to noise).
:param bool exp_corr: Should signal to noises be measured with exposure time correction, default is True. I
recommend that this be true for combined observations, as exposure time could change quite dramatically
across the combined product.
:param bool group_spec: A boolean flag that sets whether generated spectra are grouped or not.
:param float min_counts: If generating a grouped spectrum, this is the minimum number of counts per channel.
To disable minimum counts set this parameter to None.
:param float min_sn: If generating a grouped spectrum, this is the minimum signal to noise in each channel.
To disable minimum signal to noise set this parameter to None.
:param float over_sample: The minimum energy resolution for each group, set to None to disable. e.g. if
over_sample=3 then the minimum width of a group is 1/3 of the resolution FWHM at that energy.
:param bool one_rmf: This flag tells the method whether it should only generate one RMF for a particular
ObsID-instrument combination - this is much faster in some circumstances, however the RMF does depend
slightly on position on the detector.
:param bool freeze_met: Whether the metallicity parameter in the fits to annuli in XSPEC should be frozen.
:param str abund_table: The abundance table to use during the XSPEC fits.
:param Quantity temp_lo_en: The lower energy limit for the XSPEC fits to annular spectra.
:param Quantity temp_hi_en: The upper energy limit for the XSPEC fits to annular spectra.
:param int num_cores: The number of cores to use (if running locally), default is set to 90% of available.
:return: A list of non-scalar astropy quantities containing the annular radii used to generate the
projected temperature profiles created by this function. Each Quantity element of the list corresponds
to a source.
:rtype: List[Quantity]
"""
if outer_radii != 'region':
inn_rad_vals, out_rad_vals = region_setup(sources, outer_radii, Quantity(0, 'arcsec'), True, '')[1:]
else:
raise NotImplementedError("I don't currently support fitting region spectra")
if all([use_combined, use_worst]):
warn("You have passed both use_combined and use_worst as True. use_worst overrides use_combined, so the "
"worst observation for each source will be used to decide on the annuli.")
use_combined = False
elif all([not use_combined, not use_worst]):
warn("You have passed both use_combined and use_worst as False. One of them must be True, so here we default"
" to using the combined data to decide on the annuli.")
use_combined = True
if abund_table not in ABUND_TABLES:
avail_abund = ", ".join(ABUND_TABLES)
raise ValueError("{a} is not a valid abundance table choice, please use one of the "
"following; {av}".format(a=abund_table, av=avail_abund))
if isinstance(sources, BaseSource):
sources = [sources]
all_rads = []
for src_ind, src in enumerate(sources):
if use_combined:
# This is the simplest option, we just use the combined ratemap to decide on the annuli with minimum SNR
rads, snrs, ma = _snr_bins(src, out_rad_vals[src_ind], min_snr, min_width, lo_en, hi_en, psf_corr=psf_corr,
psf_model=psf_model, psf_bins=psf_bins, psf_algo=psf_algo, psf_iter=psf_iter,
allow_negative=allow_negative, exp_corr=exp_corr)
else:
# This way is slightly more complicated, but here we use the worst observation (ranked by global
# signal to noise).
# The return for this function is ranked worst to best, so we grab the first row (which is an ObsID and
# instrument), then call _snr_bins with that one
lowest_ranked = src.snr_ranking(out_rad_vals[src_ind], lo_en, hi_en, allow_negative)[0][0, :]
rads, snrs, ma = _snr_bins(src, out_rad_vals[src_ind], min_snr, min_width, lo_en, hi_en, lowest_ranked[0],
lowest_ranked[1], psf_corr, psf_model, psf_bins, psf_algo, psf_iter,
allow_negative, exp_corr)
# Shoves the annuli we've decided upon into a list for single_temp_apec_profile to use
all_rads.append(rads)
if len(sources) == 1:
sources = sources[0]
single_temp_apec_profile(sources, all_rads, group_spec=group_spec, min_counts=min_counts, min_sn=min_sn,
over_sample=over_sample, one_rmf=one_rmf, num_cores=num_cores, abund_table=abund_table,
lo_en=temp_lo_en, hi_en=temp_hi_en, freeze_met=freeze_met)
return all_rads
[docs]def min_cnt_proj_temp_prof(sources: Union[GalaxyCluster, ClusterSample], outer_radii: Union[Quantity, List[Quantity]],
min_cnt: Union[int, Quantity] = Quantity(1000, 'ct'),
min_width: Quantity = Quantity(20, 'arcsec'), use_combined: bool = True,
lo_en: Quantity = Quantity(0.5, 'keV'), hi_en: Quantity = Quantity(2, 'keV'),
psf_corr: bool = False, psf_model: str = "ELLBETA", psf_bins: int = 4, psf_algo: str = "rl",
psf_iter: int = 15, group_spec: bool = True, min_counts: int = 5, min_sn: float = None,
over_sample: float = None, one_rmf: bool = True, freeze_met: bool = True,
abund_table: str = "angr", temp_lo_en: Quantity = Quantity(0.3, 'keV'),
temp_hi_en: Quantity = Quantity(7.9, 'keV'), num_cores: int = NUM_CORES) -> List[Quantity]:
"""
This is a convenience function that allows you to quickly and easily start measuring projected
temperature profiles of galaxy clusters, deciding on the annular bins using X-ray count measurements
from photometric products. This function calls single_temp_apec_profile, but doesn't necessarily expose
all of single_temp_apec_profile's variables, so if you want more control, then use single_temp_apec_profile
directly. The projected temperature profiles which are generated are added to their source's storage structure.
:param GalaxyCluster/ClusterSample sources: An individual or sample of sources to measure projected
temperature profiles for.
:param str/Quantity outer_radii: The name or value of the outer radius to use for the generation of
the spectra (for instance 'r200' would be acceptable for a GalaxyCluster, or Quantity(1000, 'kpc')). If
'region' is chosen (to use the regions in region files), then any inner radius will be ignored. If you are
generating for multiple sources then you can also pass a Quantity with one entry per source.
:param float min_cnt: The minimum counts allowable in a given annulus.
:param Quantity min_width: The minimum allowable width of an annulus. The default is set to 20 arcseconds to try
and avoid PSF effects.
:param bool use_combined: If True then the combined RateMap will be used for count annulus calculations.
Default is True, if False then the median ObsID-Instrument combo (in terms of background-subtracted counts
within outer_radii) will be used to generate the annuli.
:param Quantity lo_en: The lower energy bound of the ratemap to use for the count calculations.
:param Quantity hi_en: The upper energy bound of the ratemap to use for the count calculations.
:param bool psf_corr: Sets whether you wish to use a PSF corrected ratemap or not.
:param str psf_model: If the ratemap you want to use is PSF corrected, this is the PSF model used.
:param int psf_bins: If the ratemap you want to use is PSF corrected, this is the number of PSFs per
side in the PSF grid.
:param str psf_algo: If the ratemap you want to use is PSF corrected, this is the algorithm used.
:param int psf_iter: If the ratemap you want to use is PSF corrected, this is the number of iterations.
:param bool group_spec: A boolean flag that sets whether generated spectra are grouped or not.
:param float min_counts: If generating a grouped spectrum, this is the minimum number of counts per channel.
To disable minimum counts set this parameter to None.
:param float min_sn: If generating a grouped spectrum, this is the minimum signal to noise in each channel.
To disable minimum signal to noise set this parameter to None.
:param float over_sample: The minimum energy resolution for each group, set to None to disable. e.g. if
over_sample=3 then the minimum width of a group is 1/3 of the resolution FWHM at that energy.
:param bool one_rmf: This flag tells the method whether it should only generate one RMF for a particular
ObsID-instrument combination - this is much faster in some circumstances, however the RMF does depend
slightly on position on the detector.
:param bool freeze_met: Whether the metallicity parameter in the fits to annuli in XSPEC should be frozen.
:param str abund_table: The abundance table to use during the XSPEC fits.
:param Quantity temp_lo_en: The lower energy limit for the XSPEC fits to annular spectra.
:param Quantity temp_hi_en: The upper energy limit for the XSPEC fits to annular spectra.
:param int num_cores: The number of cores to use (if running locally), default is set to 90% of available.
:return: A list of non-scalar astropy quantities containing the annular radii used to generate the
projected temperature profiles created by this function. Each Quantity element of the list corresponds
to a source.
:rtype: List[Quantity]
"""
if outer_radii != 'region':
inn_rad_vals, out_rad_vals = region_setup(sources, outer_radii, Quantity(0, 'arcsec'), True, '')[1:]
else:
raise NotImplementedError("I don't currently support fitting region spectra")
if abund_table not in ABUND_TABLES:
avail_abund = ", ".join(ABUND_TABLES)
raise ValueError("{a} is not a valid abundance table choice, please use one of the "
"following; {av}".format(a=abund_table, av=avail_abund))
# Makes sure that sources is iterable, even if its just a single source - makes writing the rest of this
# function a bit neater.
if isinstance(sources, BaseSource):
sources = [sources]
all_rads = []
for src_ind, src in enumerate(sources):
if use_combined:
# This is the simplest option, we just use the combined ratemap to decide on the annuli with minimum counts
rads, cnts, ma = _cnt_bins(src, out_rad_vals[src_ind], min_cnt, min_width, lo_en, hi_en, psf_corr=psf_corr,
psf_model=psf_model, psf_bins=psf_bins, psf_algo=psf_algo, psf_iter=psf_iter)
else:
# Use the source's built in count ranking method (which in turn uses some RateMap class methods) to rank
# the individual observations (cnt_rnk is ObsID, Instrument combinations in order of ascending counts).
# We then use the counts measured for each ObsID-Instrument combo (which are returned and stored in cnts)
# to decide upon the median observation.
cnt_rnk, cnts = src.count_ranking(out_rad_vals[src_ind], lo_en, hi_en)
# Obviously the median counts will not necessarily line up with any particular ObsID-instrument, but we
# can use the interpolation feature of numpy percentile to find the nearest existing counts to the
# median counts.
med_obs_ind = np.argwhere(cnts == np.percentile(cnts, 50, interpolation='nearest'))[0]
# This pulls out the ObsID and instrument that we have chosen to base the annular bins on.
med_obs_id = cnt_rnk[med_obs_ind, 0][0]
med_obs_inst = cnt_rnk[med_obs_ind, 1][0]
# In this instance though, we use the median (in terms of background subtracted counts)
# individual (as in individual instrument too) observation to construct the annuli.
rads, cnts, ma = _cnt_bins(src, out_rad_vals[src_ind], min_cnt, min_width, lo_en, hi_en, med_obs_id,
med_obs_inst, psf_corr, psf_model, psf_bins, psf_algo, psf_iter)
# Shoves the annuli we've decided upon into a list for single_temp_apec_profile to use
all_rads.append(rads)
# Reverses a bodge employed at the beginning of this function
if len(sources) == 1:
sources = sources[0]
# This runs the fitting (and generation, if that has not already occurred) of the annular spectra.
single_temp_apec_profile(sources, all_rads, group_spec=group_spec, min_counts=min_counts, min_sn=min_sn,
over_sample=over_sample, one_rmf=one_rmf, num_cores=num_cores, abund_table=abund_table,
lo_en=temp_lo_en, hi_en=temp_hi_en, freeze_met=freeze_met)
return all_rads
def _grow_ann_proj_temp_prof(sources: Union[BaseSource, BaseSample], outer_radii: Union[Quantity, List[Quantity]],
growth_factor: float = 1.3, start_radius: Quantity = Quantity(20, 'arcsec'),
num_ann: int = None, group_spec: bool = True, min_counts: int = 5, min_sn: float = None,
over_sample: float = None, one_rmf: bool = True, num_cores: int = NUM_CORES):
"""
This is a convenience function that allows you to quickly and easily start measuring projected temperature
profiles of galaxy clusters where the outer radius of each annulus is some factor larger than that of the
last annulus:
.. math::
R_{i+1} = R_{i}F
If a growth factor is passed then the start radius and outer radius of a particular source will be used to solve
for the number of annuli which should be generated. However if a number of annuli is passed (through num_ann),
then this function will again use the start and outer radii and solve for the growth factor instead, over-riding
any growth factor that may have been passed in.
This function calls single_temp_apec_profile, but doesn't expose all of the more
in depth variables, so if you want more control then use single_temp_apec_profile directly. The projected
temperature profiles which are generated are added to their source's storage structure.
:param GalaxyCluster/ClusterSample sources: An individual or sample of sources to measure projected
temperature profiles for.
:param str/Quantity outer_radii: The name or value of the outer radius to use for the generation of
the spectra (for instance 'r200' would be acceptable for a GalaxyCluster, or Quantity(1000, 'kpc')). If
'region' is chosen (to use the regions in region files), then any inner radius will be ignored. If you are
generating for multiple sources then you can also pass a Quantity with one entry per source.
:param float growth_factor: The factor by which the outer radius of the Nth annulus should be larger than
the outer radius of the N-1th annulus. This will be over-ridden by a re-calculated value if a value
is passed to num_ann.
:param Quantity start_radius: The radius of the innermost circular annulus, the default is 20 arcseconds, which
was chosen to try and avoid PSF effects.
:param int num_ann: The number of annuli which should be used, default is None, in which case the value will be
calculated using the growth factor, outer radius, and start radius. If this parameter is passed then
growth_factor will be overridden by a recalculated value.
:param bool group_spec: A boolean flag that sets whether generated spectra are grouped or not.
:param float min_counts: If generating a grouped spectrum, this is the minimum number of counts per channel.
To disable minimum counts set this parameter to None.
:param float min_sn: If generating a grouped spectrum, this is the minimum signal to noise in each channel.
To disable minimum signal to noise set this parameter to None.
:param float over_sample: The minimum energy resolution for each group, set to None to disable. e.g. if
over_sample=3 then the minimum width of a group is 1/3 of the resolution FWHM at that energy.
:param bool one_rmf: This flag tells the method whether it should only generate one RMF for a particular
ObsID-instrument combination - this is much faster in some circumstances, however the RMF does depend
slightly on position on the detector.
:param int num_cores: The number of cores to use (if running locally), default is set to 90% of available.
"""
raise NotImplementedError("This doesn't work yet because I got bored")
if outer_radii != 'region':
inn_rad_vals, out_rad_vals = region_setup(sources, outer_radii, Quantity(0, 'arcsec'), True, '')[1:]
else:
raise NotImplementedError("I don't currently support fitting region spectra")
all_rads = []
for src_ind, src in enumerate(sources):
cur_start = src.convert_radius(start_radius, 'arcsec')
if num_ann is None:
cur_num_ann = int(np.ceil(np.log(out_rad_vals[src_ind].to('arcsec').value / cur_start.value)
/ np.log(growth_factor)))
cur_growth_factor = growth_factor
else:
cur_growth_factor = np.power(out_rad_vals[src_ind].to('arcsec').value / cur_start.value, 1 / num_ann)
cur_num_ann = num_ann
rads = [cur_start.value]
rads += [cur_start.value * ann_ind * cur_growth_factor for ann_ind in range(1, cur_num_ann + 1)]
print(Quantity(rads, 'arcsec'))
print('')
single_temp_apec_profile(sources, all_rads, group_spec=group_spec, min_counts=min_counts, min_sn=min_sn,
over_sample=over_sample, one_rmf=one_rmf, num_cores=num_cores)
[docs]def onion_deproj_temp_prof(sources: Union[GalaxyCluster, ClusterSample], outer_radii: Union[Quantity, List[Quantity]],
annulus_method: str = 'min_snr', min_snr: float = 30,
min_cnt: Union[int, Quantity] = Quantity(1000, 'ct'),
min_width: Quantity = Quantity(20, 'arcsec'), use_combined: bool = True,
use_worst: bool = False, lo_en: Quantity = Quantity(0.5, 'keV'),
hi_en: Quantity = Quantity(2, 'keV'), psf_corr: bool = False, psf_model: str = "ELLBETA",
psf_bins: int = 4, psf_algo: str = "rl", psf_iter: int = 15, allow_negative: bool = False,
exp_corr: bool = True, group_spec: bool = True, min_counts: int = 5, min_sn: float = None,
over_sample: float = None, one_rmf: bool = True, freeze_met: bool = True,
abund_table: str = "angr", temp_lo_en: Quantity = Quantity(0.3, 'keV'),
temp_hi_en: Quantity = Quantity(7.9, 'keV'), num_data_real: int = 300,
sigma: int = 1, num_cores: int = NUM_CORES) \
-> List[GasTemperature3D]:
"""
This function will generate de-projected, three-dimensional, gas temperature profiles of galaxy clusters using
the 'onion peeling' deprojection method. It will also generate any projected temperature profiles that may be
necessary, using the method specified in the function call (the default is the minimum signal to noise annuli
method). As a side effect of that process APEC normalisation profiles will also be created, as well as Emission
Measure profiles. The function is an implementation of a fairly old technique, though it has been used recently
in https://doi.org/10.1051/0004-6361/201731748. For a more in depth discussion of this technique and its uses
I would currently recommend https://doi.org/10.1051/0004-6361:20020905.
:param GalaxyCluster/ClusterSample sources: An individual or sample of sources to calculate 3D temperature
profiles for.
:param str/Quantity outer_radii: The name or value of the outer radius to use for the generation of
the spectra (for instance 'r200' would be acceptable for a GalaxyCluster, or Quantity(1000, 'kpc')). If
'region' is chosen (to use the regions in region files), then any inner radius will be ignored. If you are
generating for multiple sources then you can also pass a Quantity with one entry per source.
:param str annulus_method: The method by which the annuli are designated, this can be 'min_snr' (which will use
the min_snr_proj_temp_prof function), or 'min_cnt' (which will use the min_cnt_proj_temp_prof function).
:param float min_snr: The minimum signal-to-noise which is allowable in a given annulus, used if annulus_method
is set to 'min_snr'.
:param int/Quantity min_cnt: The minimum background subtracted counts which are allowable in a given annulus, used
if annulus_method is set to 'min_cnt'.
:param Quantity min_width: The minimum allowable width of an annulus. The default is set to 20 arcseconds to try
and avoid PSF effects.
:param bool use_combined: If True (and annulus_method is set to 'min_snr') then the combined RateMap will be
used for signal-to-noise annulus calculations, this is overridden by use_worst. If True (and annulus_method
is set to 'min_cnt') then combined RateMaps will be used for annulus count calculations, if False then
the median observation (in terms of counts) will be used.
:param bool use_worst: If True then the worst observation of the cluster (ranked by global signal-to-noise) will
be used for signal-to-noise annulus calculations. Used if annulus_method is set to 'min_snr'.
:param Quantity lo_en: The lower energy bound of the RateMap to use for the signal-to-noise or background
subtracted count calculations.
:param Quantity hi_en: The upper energy bound of the RateMap to use for the signal-to-noise or background
subtracted count calculations.
:param bool psf_corr: Sets whether you wish to use a PSF corrected RateMap or not.
:param str psf_model: If the RateMap you want to use is PSF corrected, this is the PSF model used.
:param int psf_bins: If the RateMap you want to use is PSF corrected, this is the number of PSFs per
side in the PSF grid.
:param str psf_algo: If the RateMap you want to use is PSF corrected, this is the algorithm used.
:param int psf_iter: If the RateMap you want to use is PSF corrected, this is the number of iterations.
:param bool allow_negative: Should pixels in the background subtracted count map be allowed to go below
zero, which results in a lower signal-to-noise (and can result in a negative signal-to-noise).
:param bool exp_corr: Should signal to noises be measured with exposure time correction, default is True. I
recommend that this be true for combined observations, as exposure time could change quite dramatically
across the combined product.
:param bool group_spec: A boolean flag that sets whether generated spectra are grouped or not.
:param float min_counts: If generating a grouped spectrum, this is the minimum number of counts per channel.
To disable minimum counts set this parameter to None.
:param float min_sn: If generating a grouped spectrum, this is the minimum signal to noise in each channel.
To disable minimum signal to noise set this parameter to None.
:param float over_sample: The minimum energy resolution for each group, set to None to disable. e.g. if
over_sample=3 then the minimum width of a group is 1/3 of the resolution FWHM at that energy.
:param bool one_rmf: This flag tells the method whether it should only generate one RMF for a particular
ObsID-instrument combination - this is much faster in some circumstances, however the RMF does depend
slightly on position on the detector.
:param bool freeze_met: Whether the metallicity parameter in the fits to annuli in XSPEC should be frozen.
:param str abund_table: The abundance table to use both for the conversion from n_exn_p to n_e^2 during density
calculation, and the XSPEC fit.
:param Quantity temp_lo_en: The lower energy limit for the XSPEC fits to annular spectra.
:param Quantity temp_hi_en: The upper energy limit for the XSPEC fits to annular spectra.
:param int num_data_real: The number of random realisations to generate when propagating profile uncertainties.
:param int sigma: What sigma uncertainties should newly created profiles have, the default is 1σ.
:param int num_cores: The number of cores to use (if running locally), default is set to 90% of available.
:return: A list of the 3D temperature profiles measured by this function, though if the measurement was not
successful an entry of None will be added to the list.
:rtype: List[GasTemperature3D]
"""
if annulus_method not in ALLOWED_ANN_METHODS:
a_meth = ", ".join(ALLOWED_ANN_METHODS)
raise ValueError("That is not a valid method for deciding where to place annuli, please use one of "
"these; {}".format(a_meth))
if annulus_method == 'min_snr':
# This returns the boundary radii for the annuli
ann_rads = min_snr_proj_temp_prof(sources, outer_radii, min_snr, min_width, use_combined, use_worst, lo_en,
hi_en, psf_corr, psf_model, psf_bins, psf_algo, psf_iter, allow_negative,
exp_corr, group_spec, min_counts, min_sn, over_sample, one_rmf, freeze_met,
abund_table, temp_lo_en, temp_hi_en, num_cores)
elif annulus_method == 'min_cnt':
# This returns the boundary radii for the annuli, based on a minimum number of counts per annulus
ann_rads = min_cnt_proj_temp_prof(sources, outer_radii, min_cnt, min_width, use_combined, lo_en, hi_en,
psf_corr, psf_model, psf_bins, psf_algo, psf_iter, group_spec, min_counts,
min_sn, over_sample, one_rmf, freeze_met, abund_table, temp_lo_en, temp_hi_en,
num_cores)
elif annulus_method == "growth":
raise NotImplementedError("This method isn't implemented yet")
# So we can iterate through sources without worrying if there's more than one cluster
if not isinstance(sources, (BaseSample, list)):
sources = [sources]
all_3d_temp_profs = []
# Don't need to check abundance table input because that happens in min_snr_proj_temp_prof
for src_ind, src in enumerate(sources):
cur_rads = ann_rads[src_ind]
try:
# The projected temperature profile we're going to use
proj_temp = src.get_proj_temp_profiles(cur_rads, group_spec, min_counts, min_sn, over_sample)
# The normalisation profile(s) from the fit that produced the projected temperature profile.
apec_norm_prof = src.get_apec_norm_profiles(cur_rads, group_spec, min_counts, min_sn, over_sample)
except NoProductAvailableError:
warn("{s} doesn't have a matching projected temperature profile, skipping.")
all_3d_temp_profs.append(None)
continue
# We need to check if a matching 3D temperature profile has already been generated, as then we
# just use that one rather than making another (which would be silly and also eat up more storage
# because they are automatically saved to disk).
try:
existing_3d_temp_prof = src.get_3d_temp_profiles(set_id=proj_temp.set_ident)
all_3d_temp_profs.append(existing_3d_temp_prof)
continue
except NoProductAvailableError:
pass
obs_id = 'combined'
inst = 'combined'
# There are reasons that a projected temperature profile can be considered unusable, so we must check. Also
# make sure to only use those profiles that have a minimum of 4 annuli. The len operator retrieves the number
# of radial data points a profile has
if proj_temp.usable and len(proj_temp) > 3:
# Also make an Emission Measure profile, used for weighting the contributions from different
# shells to annuli
em_prof = apec_norm_prof.emission_measure_profile(src.redshift, src.cosmo, abund_table,
num_data_real, sigma)
src.update_products(em_prof)
# Need to make sure the annular boundaries are a) in a proper distance unit rather than degrees, and b)
# in units of centimeters
cur_rads = src.convert_radius(cur_rads, 'cm')
# Use a handy function I wrote to calculate the volume intersections of spherical shells and
# projected annuli
vol_intersects = shell_ann_vol_intersect(cur_rads, cur_rads)
# Then its a simple inverse problem to recover the 3D temperatures
temp_3d = (np.linalg.inv(vol_intersects.T) @ (proj_temp.values * em_prof.values)) / (np.linalg.inv(
vol_intersects.T) @ em_prof.values)
# I generate random realisations of the projected temperature profile and the emission measure profile
# to help me with error propagation
proj_temp_reals = proj_temp.generate_data_realisations(num_data_real)
em_reals = em_prof.generate_data_realisations(num_data_real)
# Set up an N x R array for the random realisations of the 3D temperature, where N is the number
# of realisations and R is the number of radius data points
temp_3d_reals = Quantity(np.zeros(proj_temp_reals.shape), proj_temp_reals.unit)
for i in range(0, num_data_real):
# Calculate and store the 3D temperature profile realisations
interim = (np.linalg.inv(vol_intersects.T) @ (proj_temp_reals[i, :] * em_reals[i, :])) / (np.linalg.inv(
vol_intersects.T) @ em_reals[i, :])
temp_3d_reals[i, :] = interim
# Calculate a standard deviation for each bin to use as the uncertainty
temp_3d_sigma = np.std(temp_3d_reals, axis=0) * sigma
# And finally actually set up a 3D temperature profile
temp_3d_prof = GasTemperature3D(proj_temp.radii, temp_3d, proj_temp.centre, src.name, obs_id, inst,
proj_temp.radii_err, temp_3d_sigma, proj_temp.set_ident,
proj_temp.associated_set_storage_key, proj_temp.deg_radii)
src.update_products(temp_3d_prof)
all_3d_temp_profs.append(temp_3d_prof)
else:
warn("The projected temperature profile for {src} is not considered usable by XGA".format(src=src.name))
all_3d_temp_profs.append(None)
return all_3d_temp_profs
```