def query_NED(
name,
config,
RA="RA",
DEC="DEC",
z="Redshift",
RAf="RA",
DECf="DEC",
origin="Origin",
):
"""
Use astroquery to query the NED database
Input:
name: name of the source to query region for
config: configuration
RA, DEC: optional, coordinates of RA and DEC columns; defaults to vizier
names which point to RA and DEC homogenized to deg and J2000
Return:
Final table containing 4 columns, RA, DEC, redshift and origin of
redshift measurement, compiled from all data available of Vizier
"""
# Query NED for the region around source within radius
try:
ned_result = Ned.query_region_async(
name, radius=config.radius).text.encode()
except Exception as e:
print(e)
raise NedQueryFailed()
cat_vot = parse(BytesIO(ned_result), pedantic=False, invalid="mask")
cat_vot = cat_vot.get_first_table().to_table(use_names_over_ids=True)
# Filter the catalog, to remove useless rows
filtered_cat = filter_ned_cat(cat_vot, RA, DEC)
# Initialize a list of table to be appended; These will be table that have
# a redshift measurement
row_list = []
# Do another NED targeted search on each of the targets to check what type
# of redshift it has associated
for line in filtered_cat:
if redshift_type(line, RA, DEC, config.uncertainty) is not None:
row_list.append(line[RA, DEC, "Redshift"])
# Vstack all the lines into a single catalogue
if not row_list:
return None
final_cat = vstack(row_list)
# Rename columns to match general choice
final_cat.rename_column("Redshift", z)
final_cat.rename_column(RA, RAf)
final_cat.rename_column(DEC, DECf)
# Add origin column as NED
final_cat.add_column(Column(["NED"] * len(final_cat)), name=origin)
return final_cat
