Crossmatch Access¶
The ALeRCE catsHTM API Wrapper gives an easy access to our crossmatch API that uses catsHTM.
Conesearch¶
To get all the objects inside a radius in a specified catalog, we use
catshtm_conesearch()
, where ra,`dec` is the
center of the search and radius is the search radius in [arcsec].
from alerce.core import Alerce
#Import ALeRCE Client
client = Alerce()
ra = 10
dec = 20
radius = 1000
catalog_name = "GAIA/DR1"
cone_objects = client.catshtm_conesearch(ra,
dec,
radius,
catalog_name,
format="pandas")
Note
Without the catalog_name argument the function will return a dictionary with all available catalogs and the value is the conesearch in those catalogs.
Crossmatch¶
Similar to Conesearch, we look for the objects in a radius, but just get the
closest object (catshtm_crossmatch()
). This method is better used for a small radius.
ra = 10
dec = 20
radius = 20
catalog_name = "GAIA/DR1"
xmatch_objects = client.catshtm_crossmatch(ra,
dec,
radius,
catalog_name,
format="pandas")
Note
Without the catalog_name argument the function will return a dictionary with all available catalogs and the value is the crossmatch in those catalogs.
Redshift¶
Search if there is available redshift in a catsHTM catalog given position
and a radius (catshtm_redshift()
).
catalog_name = "GAIA/DR1"
redshift = client.catshtm_redshift(ra,
dec,
radius,
catalog_name)