IRSA-7363 Document spherex SIA delay

Author: troyraen

tutorials/spherex/spherex_cutouts.md

@@ -83,6 +83,7 @@ bandpass = 'SPHEREx-D2'
 output_filename = 'spherex_cutouts_mef.fits'
 ```
 
+(spherex-query-tap)=
 ## 5. Query IRSA for a list of cutouts that satisfy the criteria specified above.
 
 Here we show how to use the `pyvo` TAP SQL query to retrieve all images that overlap with the position defined above.
@@ -117,6 +118,11 @@ print("Time to do TAP query: {:2.2f} seconds.".format(time.time() - t1))
 print("Number of images found: {}".format(len(results)))
 ```
 
+:::{note}
+SPHEREx data are also available via SIA which can provide a simpler interface for many queries, as demonstrated in {ref}`spherex-query-sia`.
+An advantage of the method shown above is that it provides access to data immediately after ingestion (which occurs weekly) and is not subject to the same ~1 day delay as SIA.
+:::
+
 ## 6. Define a function that processes a list of SPHEREx Spectral Image Cutouts
 
 This function takes in a row of the catalog that we created above and does the following:

tutorials/spherex/spherex_intro.md

@@ -65,6 +65,7 @@ from astroquery.ipac.irsa import Irsa
 from firefly_client import FireflyClient
 ```
 
+(spherex-query-sia)=
 ## 5. Search for SPHEREx Spectral Image MEFs that overlap coordinates you are interested in
 
 +++
@@ -102,6 +103,12 @@ There are currently three collections available for the second Quick Release:
 results = Irsa.query_sia(pos=(coord, search_radius), collection='spherex_qr2')
 ```
 
+:::{note}
+SPHEREx data are ingested on a weekly basis.
+Due to the nature of the ingestion process, availability via SIA will lag on the order of a day.
+To avoid this delay, users can access data through the browsable directories or the SPHEREx Data Explorer GUI (see [SPHEREx Data Access](https://caltech-ipac.github.io/spherex-archive-documentation/spherex-data-access)), or do a TAP query as shown in {ref}`spherex-query-tap`.
+:::
+
 Each row of the results of your query represents a different spectral image.
 Because SPHEREx data will be released on a weekly basis, the number of rows returned will change
 depending on when you submit the query.