def growing_aperture_paper():
filename = "./data/Pisco.cii.455kms.image.fits"
ra, dec = (205.533741, 9.477317341) # we know where the source is
redshift = (1900.538 / 222.547) - 1 # redshift from the observed line peak, z= freq_rest_CII / freq_obs - 1
aper_rad = 1.3 # final manually chosen aperture radius
mcub = MultiCube(filename) # load maps
# This map is a single channel collapse over a [CII] emission line, total width of 455 km/s
# If line fluxes in units of Jy.km/s are preferred, use the lower scaling
scale = mcub["image"].deltavel() # channel width in kms
radius, flux, err, tab = mcub.growing_aperture_corrected(ra=ra, dec=dec, maxradius=3, calc_error=True)
# tab.write("growth.txt", format="ascii.fixed_width", overwrite=True) # save results in a human readable format
fig, ax = plt.subplots(figsize=(4.8, 3))
ax.plot(radius, flux * scale, color="firebrick", lw=2, label="Corrected")
ax.fill_between(radius, (flux - err) * scale, (flux + err) * scale, color="firebrick", lw=0, alpha=0.2)
ax.plot(radius, tab["flux_image"] * scale, label="Uncorrected", ls="--", color="gray")
ax.axvline(aper_rad, color="gray", lw=0.75, ls=":", label="Chosen aperture size")
# Could obtain just the single flux value at given aper_rad with
# flux, err, tab = mcub.spectrum_corrected(ra=ra, dec=dec, radius=aper_rad, calc_error=True)
# print(flux*scale,err*scale)
ax.tick_params(direction='in', which="both")
ax.set_xlabel("Aperture radius (arcsec)")
ax.set_ylabel("Line flux density (Jy km/s)")
ax.set_xlim(0, 3)
ax.legend(loc="lower right", frameon=False)
# add physical distances scale
kpc_per_arcsec = iftools.arcsec2kpc(redshift)
ax2 = ax.twiny()
ax2.set_xlim(ax.get_xlim()[0] * kpc_per_arcsec, ax.get_xlim()[1] * kpc_per_arcsec)
ax2.set_xlabel("Radius (kpc)")
ax2.tick_params(direction='in', which="both")
plt.savefig("./plots/growing_aperture_paper.pdf", bbox_inches="tight") # save plot
plt.savefig("./thumbnails/growing_aperture_paper.png", bbox_inches="tight", dpi=72) # web raster version
plt.show()
def growing_aperture_technical():
"""
Compute curve of growths in multiple maps up to some maximum radius.
Derive corrected flux using residual scaling.
"""
filename = "./data/Pisco.cii.455kms.image.fits"
ra, dec = (205.533741, 9.477317341) # we know where the source is
scale = 1e3 # map units are Jy/beam, will use to scale fluxes to mJy/beam
mcub = MultiCube(filename) # load maps
radius, flux, err, tab = mcub.growing_aperture_corrected(ra=ra, dec=dec, maxradius=3, calc_error=True)
# tab.write("growth.txt", format="ascii.fixed_width", overwrite=True) # save results in a human readable format
fig, ax = plt.subplots(figsize=(4.8, 3))
ax.set_title("Curves of growth")
ax.plot(radius, flux * scale, color="firebrick", lw=2, label="Corrected")
ax.fill_between(radius, (flux - err) * scale, (flux + err) * scale, color="firebrick", lw=0, alpha=0.2)
ax.plot(radius, tab["flux_dirty"] * scale, label="Dirty", color="black", ls=":")
ax.plot(radius, tab["flux_clean"] * scale, label="Cleaned components only", ls="-.", color="navy")
ax.plot(radius, tab["flux_residual"] * scale, label="Residual", ls="--", color="orange")
ax.plot(radius, tab["flux_image"] * scale, label="Uncorrected: clean + residual", dashes=[10, 3],
color="forestgreen")
ax.plot(radius, tab["epsilon"], color="gray", label="Clean-to-dirty beam ratio")
ax.axhline(0, color="gray", lw=0.5, ls=":")
ax.tick_params(direction='in', which="both")
ax.set_xlabel("Radius (arcsec)")
ax.set_ylabel("Cumulative flux density (mJy)")
ax.tick_params(direction='in', which="both")
ax.set_xlim(0, 3)
ax.legend(bbox_to_anchor=(1, 0.8))
plt.savefig("./plots/growing_aperture_technical.pdf", bbox_inches="tight") # save plot
plt.savefig("./thumbnails/growing_aperture_technical.png", bbox_inches="tight", dpi=72) # web raster version
plt.show()