nb7. Query by sensitivity |
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In this notebook we query the observations of higher sensitivity at a given resolution.
The relevant columns in the ALMA Archive datasets are
Import all necessary modules:
from astropy.table import Table
import pandas as pd
pd.set_option('display.max_columns', None)
import numpy as np
import pyvo
import matplotlib.pyplot as plt
service = pyvo.dal.TAPService("https://almascience.eso.org/tap") # for the EU ALMA TAP service
# service = pyvo.dal.TAPService("https://almascience.nao.ac.jp/tap") # for the EA ALMA TAP service
# service = pyvo.dal.TAPService("https://almascience.nrao.edu/tap") # for the NA ALMA TAP service
This function queries the (spectroscopic) observations with a given science keyword, which have ALMA observations at sensitivities smaller than the given value.
def query_line_sensitivity(service, science_keyword, sensitivity_10kms_max):
"""Queries the science observations with the given keyword for sensitivities smaller than the given sensitivity
service pyvo TAPService instance
science_keyword one of the science keywords (see Notebook 4, Example 4a or the ALMA Science Archive query interface)
sensitivity_10kms_max maximum sensitivity in a 10km/s bandwidth bin in mJy/beam (see Notebook 0 for all columns and units)
returns pandas table
"""
query = f"""
SELECT *
FROM ivoa.obscore
WHERE science_keyword like '%{science_keyword}%'
AND science_observation = 'T'
AND sensitivity_10kms < {sensitivity_10kms_max}
"""
return service.search(query).to_table().to_pandas()
This function queries the (continuum) observations with a given science keyword, which have ALMA observations at sensitivities smaller than the given value.
def query_continuum_sensitivity(service, science_keyword, continuum_sensitivity_max):
"""Queries the observations of a given scientific keyword for their aggregate continuum sensitivity
service pyvo TAPService instance
science_keyword one of the science keywords (see Notebook 4, Example 4a or the ALMA Science Archive query interface)
continuum_sensitivity_max maximum sensitivity in the aggregate bandwidth in mJy/beam (see Notebook 0 for all columns and units)
returns pandas table
"""
query = f"""
SELECT *
FROM ivoa.obscore
WHERE science_keyword like '%{science_keyword}%'
AND science_observation = 'T'
AND cont_sensitivity_bandwidth < {continuum_sensitivity_max}
"""
return service.search(query).to_table().to_pandas()
output = query_continuum_sensitivity(service, 'Starburst galaxies', 0.1)
plt.rcParams["figure.figsize"] = (20,10)
output.plot(kind='scatter', x='s_ra', y='s_dec', c='cont_sensitivity_bandwidth', s=15, alpha=0.3, colormap='viridis')
<AxesSubplot:xlabel='s_ra', ylabel='s_dec'>
