<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">Hi Francois,<div><br></div><div>That is very helpful, but I’m a little unclear as to all the implications.</div><div><br></div><div>I note that section B.1.2 specifically referees to the vocabulary RDF so you have the option of using the vocabulary for dataproduct_subtype. However, this option is specifically NOT mentioned in the ObsCore Recommendation in association with dataproduct_type, so formally that implies using the vocabulary with the latter is not allowed (and that makes sense given that the Recommendation defines specific classifications for dataproduct_type).</div><div><br></div><div>However, if I look at <a href="https://www.ivoa.net/rdf/product-type/2024-05-19/product-type.html">https://www.ivoa.net/rdf/product-type/2024-05-19/product-type.html</a> there are no constraints identified as to where specific terms may be used, and the text of section B.1.2 similarly imposes no constraints. That would seem to allow me to (for example) specify</div><div>dataproduct_type = image and dataproduct_subtype = spatially-resolved-dataset, which would invert the parent-child relationship (or even dataproduct_type = sed, dataproduct_subtype = time-cube as an extreme example) as there is no formal relationship defined between the enumerated dataproduct_types in the Recommendation and the RDF vocabulary entries that can be used for dataproduct_subtype.</div><div><br></div><div>I assume the formalisms needed to make these play cleanly together have yet to be developed?</div><div><br></div><div>(This is separate from my previous comments at the Malta Interop regarding the lack of rigorous definitions for some of the vocabulary entries that makes it unclear whether they do or do not work for HEA data.)</div><div><br></div><div>Thanks,</div><div>—Ian</div><div><div><br><blockquote type="cite"><div>On May 28, 2025, at 16:24, BONNAREL FRANCOIS gmail <francois.bonnarel@gmail.com> wrote:</div><br class="Apple-interchange-newline"><div>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<div>
<div class="moz-cite-prefix">Hi Ian, all,</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">1 ) Using a new IVOA vocabulary for
"response functions" in the dataproduct_subtype of ObsCore is
perfectly allowed</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">See this section of the spec</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">
<blockquote type="cite">B.1.2. Data Product Subtype
(dataproduct_subtype)<br>
In order to be more precise the data product type may be refined
with a second field, the data<br>
product subtype. Unlike the more generic dataproduct_type, this
field is intended to precisely<br>
specify the scientific nature of the data product, possibly in
terms relevant only to a specific<br>
archive or data collection. While less useful for global data
discovery this allows the data<br>
products within a specific archive to be precisely identified
and referenced in queries of that<br>
specific archive. The data provider should define a vocabulary
sufficient to classify all science<br>
data products in their archive to be exposed with ObsTAP. In the
future we may be able to<br>
define broader standards to classify data at this level,
although it will likely always be the case<br>
that data differs at the level of specific instrumental survey
data collections. The data product<br>
subtype allows data within a specific archive or data collection
to be precisely classified and<br>
referenced in subsequent discovery queries. The list of terms
defined for dataproduct_subtype<br>
labels should be published by the data centers and documented.
These can be gathered as<br>
an IVOA vocabulary in a RDF dedicated resource for instance.<br>
However, in the meantime, the vocabulary used can be discovered
easily by a simple query<br>
based on ‘select distinct …’</blockquote>
</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">Distinguishing terms which are defined
by the data provider only and others which are part of an
"official" IVOA vocabulary can easily be done*</div>
<div class="moz-cite-prefix">by using the full URI of the term in
the latter case. For example <br>
</div>
<div class="moz-cite-prefix">dataproduct_type : cube<br>
</div>
<div class="moz-cite-prefix">dataproduct_subtype :
<a class="moz-txt-link-freetext" href="https://www.google.com/url?q=https://www.ivoa.net/rdf/responsefunction_type%23psf&source=gmail-imap&ust=1749068701000000&usg=AOvVaw2sqE7d0ipURWwYDmJISHCR">https://www.ivoa.net/rdf/responsefunction_type#psf</a></div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">beside <br>
</div>
<div class="moz-cite-prefix">dataproduct_type : spectrum<br>
</div>
<div class="moz-cite-prefix">dataproduct_subtype :hard-Xray (or
whatever provider dependant term)</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix"> <br>
</div>
<div class="moz-cite-prefix">2 ) Thinking more about it and reading
one of Bruno's emails claiming that response functions may be
multi-d cubes, spectra, or images I don't think we need to set
dataproduct_type =
<a class="moz-txt-link-freetext" href="https://www.google.com/url?q=https://www.ivoa.net/rdf/responsefunction_type%23response-function&source=gmail-imap&ust=1749068701000000&usg=AOvVaw3sJAvG7qaxYzjssIFanOoD">https://www.ivoa.net/rdf/responsefunction_type#response-function</a>
(even if I wrote that a week ago).</div>
<div class="moz-cite-prefix"> </div>
<div class="moz-cite-prefix">Indeed , our IVOA vocabularies are
hierarchical and recognition software should take this into
account</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">A query with a constraint such as
"WHERE ivoa_smaller(dataproduct_subtype,<a class="moz-txt-link-freetext" href="https://www.google.com/url?q=https://www.ivoa.net/rdf/responsefunction_type%23response-function&source=gmail-imap&ust=1749068701000000&usg=AOvVaw3sJAvG7qaxYzjssIFanOoD">https://www.ivoa.net/rdf/responsefunction_type#response-function</a>")
should validate for #psf, #lsf, #arf, etc....</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">3 ) This of course would be interesting
only in the case that response function can be described by
ObsCore attributes, which is not obvious after reading the
discussion between Ian and Mireille</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">Cheers</div>
<div class="moz-cite-prefix">François<br>
</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix"><br>
</div>
<div class="moz-cite-prefix">Le 21/05/2025 à 20:16, Dr. Ian N. Evans
via heig a écrit :<br>
</div>
<blockquote type="cite" cite="mid:10869BF3-31D3-4C34-B799-ED5B778A56BF@cfa.harvard.edu">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
Hi Mireille,
<div><br>
</div>
<div>In the current draft of the HEA ObsCore note, I access a PSF
using</div>
<div><br>
</div>
<div>dataproduct_type = ‘response-function’</div>
<div>dataproduct_subtype = ‘psf’</div>
<div><br>
</div>
<div>because a PSF is a type of response-function (and there are
many types of response function so adding all of these
separately as different dataproduct_type would grow the list
very significantly. Having said that, using dataproduct_subtype
may not be ideal because there is not a vocabulary for the
latter defined in ObsCore. In the future, if we were to migrate
to a dataproduct_type vocabulary that included all the different
types of products then I might do things differently.</div>
<div><br>
</div>
<div>For Chandra, the PSF is dependent on off-axis (theta) and
azimuthal (phi) angles relative to the mirror optical axis, and
also energy (and the detector can be moved relative to the
mirror optical axis so this does not translate to detector
coordinates). Note that this also means that the PSF varies
significantly across the field of view of a single observation.
Trying to query to find a PSF in this manner would require
significant enhancements to ObsCore to support non-celestial
coordinate systems that will be facility-dependent. However, to
identify PSFs associated with a particular source detection in a
single observation, one could use a query like (current use case
A.1.3)</div>
<div><br>
</div>
<div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">SELECT
* FROM ivoa.obscore</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">WHERE</div>
</div>
<div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">(CONTAINS(POINT(s_ra,
s_dec), CIRCLE, 83.84358, -5.43639, 0.033333) = 1)</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">AND
(dataproduct_type EQ ‘response-function’)</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">AND
(dataproduct_subtype EQ ‘psf’)</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">AND
(obs_id = ‘4374’)</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">AND
(obs_collection = ‘CSC2’)</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;"><br>
</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">since
we have specified both an obs_id and a position on the sky -
which for a single observation will map to a specific (theta,
phi). This would return all PSFs for different energies for
that source detection and observation from CSC release 2.
Note that if I didn’t specify the obs_id, I would get PSFs
for all of the observations that included that location on the
sky (and the different energies) from the catalog. You would
need the obs_id to tie them to a specific observation.
However, perhaps you want to identify which (if any)
observations that include your source have PSFs that are small
enough to deblend a nearby source (this can be complicated for
Chandra since off-axis PSFs have very complex, asymmetric
structures that vary with bth theta and phi).</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;"><br>
</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">We
don’t have any extant ObsCore tables for PSFs. I have tried
to mock up a conceptual single entry ObsCore table for a
Chandra PSF - hopefully it will be helpful. I don’t know that
all the values are populated correctly, or even if the table
and column values would all validate. </div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;"><br>
</div>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;"><br>
</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">With
regard to vocabulary, I prefer “response-function” as the
higher level concept rather than “irf” (we started out with
just “response” but Markus convinced me that term was too
overloaded and “response-function” is technically correct.
Response-functions are widely applicable across multiple
wavebands. For example, a point spread function is a type of
response-function that is used across all wavebands.
Similarly, a line spread function is a response-function used
in UV through IR spectroscopy. The term “irf” is not
generally used across all high-energy projects. In the USA,
most high-energy projects follow the NASA HEASARC OGIP
standards, and so will use “rmf” for the redistribution matrix
file” and “arf” for the “auxiliary response file” (and will
keep these separate). Internationally, some projects
historically used “irf” to represent the product of the rmf
and arf. More recently some projects have used “irf” as the
equivalent of “response-function” giving it a broader
interpretation. So this can be a source of confusion and lack
of clarity. I also note that “irf” stands for “instrument
response function” and there are certainly response-functions
such as software filters (e.g., a modified Hanning filter used
for optimal extraction) where “instrument” would be a
misnomer.</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;"><br>
</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">I
might suggest something more like</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">response-function</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">arf
as child of response-function</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">rmf
as child of response-function</div>
</div>
<div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">psf
as child of response-function</div><div style="margin: 0px; font-width: normal; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">lsf
as child of response-function (not HEA)</div>
</div>
<div>...</div>
<div><br>
</div>
<div>Is irf a child of response-function? The original usage of
irf as product of rmf and arf definitely would be. Interpreted
in a more general way I would still say yes (“instrument
response function” is a child of “response function”.</div>
<div><br>
</div>
<div>I’m not convinced that background/background rate/background
noise are response-functions, and these concepts have much wider
applicability across multiple wavebands.</div>
<div><br>
</div>
<div>Cheers,</div>
<div>—Ian</div>
<div><br>
</div>
<div>
<div>
<blockquote type="cite">
<div>On May 19, 2025, at 14:43, Mireille Louys via heig
<a class="moz-txt-link-rfc2396E" href="mailto:heig@ivoa.net"><heig@ivoa.net></a> wrote:</div>
<br class="Apple-interchange-newline">
<div>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<div text="#000000" bgcolor="#FFFFFF"><p>Hi Ian, hi folks,<br>
</p><p>Thanks for the various querying scenarios. <br>
</p><p>I understand the PSF use case you describe would be
something like: <br>
</p><p>give me all dataproduct_type='psf' with additional
constraints like<br>
</p>
<div>SELECT TOP 100 * FROM ivoa.ObsCore</div>
<div>WHERE obs_id='22830' and dataproduct_type='psf'</div>
<div><br>
</div>
<div>How is the relationship between a PSF data product
with a data file? <br>
</div>
<div>through obs_id, obs_publisher_id, ? </div>
<div> <br>
</div>
<div>Can we explore how the obscore1.1 table would be
filled for a PSF data product? <br>
</div>
<div>are there file examples? <br>
</div>
<div><br>
</div>
<div>I understand we identify here a vocabulary to
identify various irf file like : "psf , irf, arf, rmf,
background noise, etc..."</div>
<div>with a kind of hierarchy like <br>
</div>
<div><i>irf</i></div>
<div><i>arf as child of irf <br>
</i></div>
<div><i>rmf as child of irf <br>
</i></div>
<div><i>psf as child of irf </i></div>
<div><i>back_ground_noise </i><br>
</div>
<div><br>
</div>
<div>with the assumption that em_ucd, sxel1, sxel2,
em_xel etc. can be filled in the Obscore table.</div>
<div>Parametric functions could not be described here.<br>
</div><p>so if these are obscore data product_types we should
be able to describe these features. <br>
</p><p>the "content_qualifier" used in data link, if I
remember well, can be something else than an obscore
data product type also. <br>
</p><p>(to be checked)</p><p>I will look deeper in this and come back on the topic
soon,</p><p>Cheers, Mireille<br>
</p><p><br>
</p>
<div class="moz-cite-prefix">Le 30/04/2025 à 19:52, Dr.
Ian N. Evans via semantics a écrit :<br>
</div>
<blockquote type="cite" cite="mid:5BA6DAF3-9C7D-4323-AE77-5E7747BFE758@cfa.harvard.edu">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div dir="auto" style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">Hi
Markus,
<div><br>
</div>
<div>See inline comments below.<br id="lineBreakAtBeginningOfMessage">
<div><br>
<blockquote type="cite">
<div>On Apr 25, 2025, at 03:29, Markus
Demleitner via heig <a class="moz-txt-link-rfc2396E" href="mailto:heig@ivoa.net" moz-do-not-send="true"><heig@ivoa.net></a>
wrote:</div>
<br class="Apple-interchange-newline">
<div>
<div>Dear Mireille,<br>
<br>
Thanks for your VEP.<br>
<br>
On Thu, Apr 24, 2025 at 06:16:36PM +0200,
Mireille Louys via semantics wrote:<br>
<blockquote type="cite">•
Proposedefinitionsforaproduct-type
*event-bundle:* An event-bundledataset<br>
is a complex object containing an
event-list and multiple files or<br>
other substructures that are products
necessary to analyse the event-list.<br>
Data in an event-bundle may thus be used
to produce higher leveldata<br>
products such as images or spectra.<br>
</blockquote>
<br>
I think the definition is reasonably clear
and applicable in<br>
practice. Before merging this, however,
I'd have a few requests for<br>
clarification:<br>
<br>
(1) used-in: I really, *really* would like
to see actual, published<br>
data here (always, in all VEPs; it's a
pain if we go into all the<br>
trouble of defining a concept and then
nobody's ever using it in<br>
practice). I see that CSC on
<a class="moz-txt-link-freetext" href="https://www.google.com/url?q=https://www.google.com/url?q%3Dhttps://www.google.com/url?q%253Dhttp://cda.cfa.harvard.edu/csctap%2526source%253Dgmail-imap%2526ust%253D1746354088000000%2526usg%253DAOvVaw0j-MeVn0RHNoz8KtLXi1tH%26source%3Dgmail-imap%26ust%3D1748285049000000%26usg%3DAOvVaw2DjRh3S8cB8tFIcUA80lAP&source=gmail-imap&ust=1749068701000000&usg=AOvVaw18-E2byHR_Abgs_u2Ac-12" moz-do-not-send="true">https://www.google.com/url?q=http://cda.cfa.harvard.edu/csctap&source=gmail-imap&ust=1746354088000000&usg=AOvVaw0j-MeVn0RHNoz8KtLXi1tH</a>
(or<br>
<a class="moz-txt-link-freetext" href="https://www.google.com/url?q=https://www.google.com/url?q%3Dhttps://www.google.com/url?q%253Dhttp://cda.cfa.harvard.edu/csc21tap%2526source%253Dgmail-imap%2526ust%253D1746354088000000%2526usg%253DAOvVaw3xeGe6fO6Vz7vemy8dYWD2%26source%3Dgmail-imap%26ust%3D1748285049000000%26usg%3DAOvVaw3UWFd1iFdeRYI9WN2Qo6bS&source=gmail-imap&ust=1749068701000000&usg=AOvVaw0YWDP5vLy-XSKx5Zx2HxME" moz-do-not-send="true">https://www.google.com/url?q=http://cda.cfa.harvard.edu/csc21tap&source=gmail-imap&ust=1746354088000000&usg=AOvVaw3xeGe6fO6Vz7vemy8dYWD2</a>
[1]) has an obscore table. It<br>
would really be excellent if they could
mark up their event bundles<br>
with the new term, such that we could say:<br>
<br>
used-in: dataset
ivo://csc.harvard.edu/scsr2?some-obs-id on
<a class="moz-txt-link-freetext" href="https://www.google.com/url?q=https://www.google.com/url?q%3Dhttps://www.google.com/url?q%253Dhttp://cda.cfa.harvard.edu/csctap%2526source%253Dgmail-imap%2526ust%253D1746354088000000%2526usg%253DAOvVaw0j-MeVn0RHNoz8KtLXi1tH%26source%3Dgmail-imap%26ust%3D1748285049000000%26usg%3DAOvVaw2DjRh3S8cB8tFIcUA80lAP&source=gmail-imap&ust=1749068701000000&usg=AOvVaw18-E2byHR_Abgs_u2Ac-12" moz-do-not-send="true">https://www.google.com/url?q=http://cda.cfa.harvard.edu/csctap&source=gmail-imap&ust=1746354088000000&usg=AOvVaw0j-MeVn0RHNoz8KtLXi1tH</a><br>
<br>
That would help me maintain a clear
consciousness when setting up the<br>
new term[2].<br>
</div>
</div>
</blockquote>
<div><br>
</div>
<div>I’m not sure that we would use event
bundles for any of the CSC data product types,
since our catalog users generally want to
discover and retrieve individual data products
(typically, many of the same data product such
as a light curve or aperture photometry MPDF
for a set of sources, such as all high
redshift quasars).</div>
<div><br>
</div>
<div>We do make event bundles available through
the Chandra Data Archive (CDA) ObsCore for
individual observations, but we have been
doing this for many years and therefore those
bundles do not conform to the proposed ObsCore
HE extension. For example, at <a href="https://www.google.com/url?q=https://www.google.com/url?q%3Dhttps://cda.harvard.edu/cxctap%26source%3Dgmail-imap%26ust%3D1748285049000000%26usg%3DAOvVaw1osNhMXJN152xT0aElNEAx&source=gmail-imap&ust=1749068701000000&usg=AOvVaw3T3Tt1aM9_4MNrRNRt5sA2" moz-do-not-send="true" class="moz-txt-link-freetext">https://cda.harvard.edu/cxctap</a> one
might do a query like</div>
<div>SELECT TOP 100</div>
<div> *</div>
<div>FROM ivoa.ObsCore</div>
<div>WHERE obs_id='22830'</div>
<div><br>
</div>
<div>The bundles currently have dataproduct_type
= ‘’ and correspond to the Chandra “primary”
and “primary” + “secondary” data product
categories for the observation. The “primary”
package includes a basic set of data products
that an observer would need to analyze the
observation and produce photometrically
calibrated spectra, while the “secondary” set
would be needed in addition if the user wanted
to recalibrate the observation with updated
calibrations (which we recommend because some
updated calibrations only become available
typically several months after an observation
is completed as calibrations such as detector
gain change with time). The bundles are
tarballs and have access_format
“application/x-tar”.</div>
<div><br>
</div>
<div>Note that our bundles do not include
responses, unlike (e.g.) CTAO. This is partly
because the spacecraft dithers on the sky
during an observation so any target moves
across the detector during the observation.
So the responses depend critically on the
user’s choice of data filtering. We follow
the HEASARC standards and provide separate RMF
and ARF data products rather than a combined
IRF. For spectral fitting, the integrated ARF
(i.e., the effective area integrated over an
energy range) also depends on the source
spectral model, so we provide tools for the
user to compute the responses and the data
products needed to do so in the “primary”
bundle. See <a href="https://www.google.com/url?q=https://www.google.com/url?q%3Dhttps://cxc.harvard.edu/cda/DataProdList.html%2523A%26source%3Dgmail-imap%26ust%3D1748285049000000%26usg%3DAOvVaw0eJtuR1mszvZkzvJoxtC64&source=gmail-imap&ust=1749068701000000&usg=AOvVaw3rBHXXBKz2UBwf4_TolKei" moz-do-not-send="true" class="moz-txt-link-freetext">https://cxc.harvard.edu/cda/DataProdList.html#A</a> for
the list of Chandra primary and secondary
products.</div>
<div><br>
</div>
<br>
<blockquote type="cite">
<div>
<div><br>
(2) Relationship: That's an operational
field, i.e., I need to create<br>
an RDF triple from this. The question
thus is: is #event-list wider<br>
than #event-bundle or is it the other way
round? I could conjure up<br>
arguments for both, so, as usual, I'd
approach the question from the<br>
user side: If I'm looking for
#event-bundle, do I want to see<br>
#event-list, too? If I'm looking for
#event-list, do I want to see<br>
#event-bundle, too? Whatever ought to
encompass the other is the<br>
wider term.<br>
</div>
</div>
</blockquote>
<div><br>
</div>
<div>I would guess probably not, but maybe. I
think an event bundle will always include the
event list, so if you are asking for an event
bundle then the event list would be redundant.
Note that an event bundle could really be a
physical bundle such as a tar file (as is the
case for Chandra) or perhaps all the products
are accessed via DataLink. If somebody asks
for an event list, they probably just want the
event list but perhaps they don’t know about
event bundles and therefore might like to see
both. There are definitely cases where they
really do want just the event list - for
example, a lot of folks are interested only in
morphological studies and, especially if they
want all observations of an object or class of
object, bundles may add a lot of extra
unwanted data volume. Would it hurt to see
them? Well if your query returns 500 event
lists and also 500 bundles it just muddies the
waters. For users of advanced data products
(e.g., Chandra Source Catalog products) I
suspect that bundles would likely never be
desired (and as I said above, I don’t think we
would provide them).</div>
<div><br>
</div>
<div>Conversely, some folks may only want
responses and not the associated event lists.
At the catalog level for example, we have
lots of folks who just want to download point
spread functions. Why? The Chandra PSF
varies strongly (~factor of 50) across the
field of view (with off-axis angle and
azimuthal angle) and also with energy. We
actually archive the local PSF for every
catalog detection at several energies, and
with ~50,000 counts. So we effectively have a
library of (currently) ~1.3 million Chandra
PSFs at several energies that are catalog
advanced data products and may save users from
having to create their own PSFs.</div>
<div><br>
</div>
<div>A lot of our actual catalog usage cases
start with users querying the catalog, then
refining their sample and retrieving a subset
of catalog data products (likely including
event lists), then retrieving additional data
products such as light curves, spectra, or
aperture photometry products as they work
through their analyses. These products are
not part of bundles, but we find this usage
pattern of wanting to retrieve additional
products in stages to be quite common for
folks who are doing archival science (vs.
those who are retrieving their own observation
data).</div>
<div><br>
</div>
<br>
<blockquote type="cite">
<div>
<div><br>
(3) Rationale: If the answer to both of
the two questions in the<br>
preceding paragraph is "Yes", then it
turns out the concepts are<br>
identical (A ⊂ B and B ⊂ A implies A = B),
and hence you really don't<br>
want a new concept but augement
#event-list to be something like,<br>
say, "Event list, possibly augmented with
ancillary information".<br>
This points to an issue with your
rationale: It basically argues that<br>
there's something you would like to say.<br>
<br>
An aphorism I'm bringing up rather often
these days is: "In protocol<br>
design, don't think about what you want to
say. Think about what<br>
others want to listen to." Hence, it's be
really great if the<br>
rationale said why someone would want to
look for #event-bundle<br>
*rather than* #event-list (or for
#event-list rather than<br>
#event-bundle, if the the former is the
narrower term). Could you<br>
provide that information in the Rationale
section?<br>
<br>
Thanks,<br>
<br>
Markus<br>
<br>
<br>
[1] Regrettably, the CSC TAP services seem
to be mildly broken at the<br>
moment. Coming in with http, they issue
https redirects which<br>
confuse TOPCAT; CXC folks: if you really
need the forced redirects<br>
(see<br>
<a class="moz-txt-link-rfc2396E" href="https://www.google.com/url?q=https://www.google.com/url?q%3Dhttps://www.google.com/url?q%253Dhttps://blog.tfiu.de/foced-https-redirects-considered-harmful.html%2526source%253Dgmail-imap%2526ust%253D1746354088000000%2526usg%253DAOvVaw2y6JI9YuzGb_dp9cgELJym%26source%3Dgmail-imap%26ust%3D1748285049000000%26usg%3DAOvVaw3Mx2gmG2CVqaJJvwc2y0Em&source=gmail-imap&ust=1749068701000000&usg=AOvVaw3tgksXl1UErZ_qMf66q5rQ" moz-do-not-send="true"><https://www.google.com/url?q=https://blog.tfiu.de/foced-https-redirects-considered-harmful.html&source=gmail-imap&ust=1746354088000000&usg=AOvVaw2y6JI9YuzGb_dp9cgELJym></a>
for<br>
a better alternative) then please update
your registry records to<br>
point to the https URIs. Even with https,
however, I'm getting a<br>
"cscrel2.dbo.obscore not found" error from
TOPCAT when running<br>
<br>
select top 30 * from ivoa.obscore where
dataproduct_type='event-list'<br>
<br>
It would be great if you could fix that
(and a regular run of stilts<br>
taplint is good practice anyway)<br>
</div>
</div>
</blockquote>
<div><br>
</div>
The https to http redirects is a known issue and
should be fixed in the next full data system
release, which is scheduled for mid-June.</div>
<div><br>
</div>
<div>We’ll look into the other issue you reported.</div>
<div><br>
</div>
<div><br>
<blockquote type="cite">
<div>
<div><br>
[2] You see,<br>
<a class="moz-txt-link-rfc2396E" href="https://www.google.com/url?q=https://www.google.com/url?q%3Dhttps://www.google.com/url?q%253Dhttps://ivoa.net/documents/Vocabularies/20230206/REC-Vocabularies-2.1.html%252523tth_sEcC.2%2526source%253Dgmail-imap%2526ust%253D1746354088000000%2526usg%253DAOvVaw0vPm8jxoQ6ePuvFWnKr6ez%26source%3Dgmail-imap%26ust%3D1748285049000000%26usg%3DAOvVaw1ycrZjjO3nsONKTFOZrKdf&source=gmail-imap&ust=1749068701000000&usg=AOvVaw3LMWSLcWjTutlm2E-tPdDi" moz-do-not-send="true"><https://www.google.com/url?q=https://ivoa.net/documents/Vocabularies/20230206/REC-Vocabularies-2.1.html%23tth_sEcC.2&source=gmail-imap&ust=1746354088000000&usg=AOvVaw0vPm8jxoQ6ePuvFWnKr6ez></a>,<br>
while not exactly normative, is clear on:<br>
<br>
In particular, ensure [...] resources
mentioned in Used-in can be<br>
reached and reflect the proposed term
[...]<br>
<br>
-- <br>
heig mailing list<br>
<a class="moz-txt-link-abbreviated moz-txt-link-freetext" href="mailto:heig@ivoa.net" moz-do-not-send="true">heig@ivoa.net</a><br>
<a class="moz-txt-link-freetext" href="https://www.google.com/url?q=https://www.google.com/url?q%3Dhttps://www.google.com/url?q%253Dhttp://mail.ivoa.net/mailman/listinfo/heig%2526source%253Dgmail-imap%2526ust%253D1746354088000000%2526usg%253DAOvVaw0wTMYFfnqD-UBwfT4NR3kr%26source%3Dgmail-imap%26ust%3D1748285049000000%26usg%3DAOvVaw3JvlR5ZVmizFNtZop7Txrj&source=gmail-imap&ust=1749068701000000&usg=AOvVaw3UGyod-EYAIg_I3GJyRFAM" moz-do-not-send="true">https://www.google.com/url?q=http://mail.ivoa.net/mailman/listinfo/heig&source=gmail-imap&ust=1746354088000000&usg=AOvVaw0wTMYFfnqD-UBwfT4NR3kr</a><br>
</div>
</div>
</blockquote>
</div>
<div><br>
</div>
<div><br>
</div>
Thanks,
<div>—Ian</div>
<div><br>
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<pre class="moz-signature" cols="72">--
--
Mireille Louys, MCF (Assistant Professor)
Centre de données Astronomiques (CDS) Equipe Images, ICube
Observatoire de Strasbourg Telecom Physique Strasbourg
11, rue de l' Université 300, Bd Sebastien Brandt CS 10413
F-67000 Strasbourg F-67412 Illkirch Cedex</pre>
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heig mailing list<br>
<a class="moz-txt-link-abbreviated" href="mailto:heig@ivoa.net">heig@ivoa.net</a><br>
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Dr. Ian Evans</span></div>
<div style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><font face="Arial"><span style="font-size: 12.666666984558105px; white-space: pre-wrap;"><b>Astrophysicist</b></span></font></div>
<div style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><font face="Arial"><span style="font-size: 12.666666984558105px; white-space: pre-wrap;"><b>Chandra X-ray Center</b></span></font></div>
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<div style="font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-family: -webkit-standard; line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><span style="font-size: 9.5pt; font-family: Arial; font-variant-ligatures: normal; font-variant-east-asian: normal; font-variant-position: normal; vertical-align: baseline; white-space: pre-wrap;">
</span></div>
<div style="font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-family: -webkit-standard; line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><span style="font-size: 9.5pt; font-family: Arial; font-variant-ligatures: normal; font-variant-east-asian: normal; font-variant-position: normal; vertical-align: baseline; white-space: pre-wrap;">Office: (617) 496 7846 | Cell: (617) 699 5152</span></div>
<div style="font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-family: -webkit-standard; line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><span style="font-family: Arial; font-size: 9.5pt; white-space: pre-wrap;">60 Garden Street | MS 81 | Cambridge, MA 02138</span></div>
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<meta charset="UTF-8"><div style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><span style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); font-family: Arial; font-size: 9.5pt; font-style: normal; font-variant-caps: normal; font-weight: 700; letter-spacing: normal; text-transform: none; white-space: pre-wrap; word-spacing: 0px; text-decoration: none; -webkit-text-stroke-width: 0px; font-variant-ligatures: normal; font-variant-east-asian: normal; font-variant-position: normal; vertical-align: baseline;">—</span></div><div style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><span style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); font-family: Arial; font-size: 9.5pt; font-style: normal; font-variant-caps: normal; font-weight: 700; letter-spacing: normal; text-transform: none; white-space: pre-wrap; word-spacing: 0px; text-decoration: none; -webkit-text-stroke-width: 0px; font-variant-ligatures: normal; font-variant-east-asian: normal; font-variant-position: normal; vertical-align: baseline;"><br class="Apple-interchange-newline">Dr. Ian Evans</span></div><div style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><font face="Arial"><span style="font-size: 12.666666984558105px; white-space: pre-wrap;"><b>Astrophysicist</b></span></font></div><div style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><font face="Arial"><span style="font-size: 12.666666984558105px; white-space: pre-wrap;"><b>Chandra X-ray Center</b></span></font></div><div style="font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-family: -webkit-standard; line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><span style="font-size: 9.5pt; font-family: Arial; background-color: rgb(255, 255, 255); font-weight: 700; font-variant-ligatures: normal; font-variant-east-asian: normal; font-variant-position: normal; vertical-align: baseline; white-space: pre-wrap;">Center for Astrophysics | Harvard & Smithsonian</span></div><div style="font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-family: -webkit-standard; line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><span style="font-size: 9.5pt; font-family: Arial; font-variant-ligatures: normal; font-variant-east-asian: normal; font-variant-position: normal; vertical-align: baseline; white-space: pre-wrap;"><br></span></div><div style="font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-family: -webkit-standard; line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><span style="font-size: 9.5pt; font-family: Arial; font-variant-ligatures: normal; font-variant-east-asian: normal; font-variant-position: normal; vertical-align: baseline; white-space: pre-wrap;">Office: (617) 496 7846 | Cell: (617) 699 5152</span></div><div style="font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-family: -webkit-standard; line-height: 1.2; margin-top: 0pt; margin-bottom: 0pt;"><span style="font-family: Arial; font-size: 9.5pt; white-space: pre-wrap;">60 Garden Street | MS 81 | Cambridge, MA 02138</span></div><br class="Apple-interchange-newline" style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);"><span style="font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none; caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);"><span><span><span><span><span><span><span><span><span><span><span><span><span style="color: rgb(0, 0, 0); font-family: Monaco; font-size: 12px; font-weight: normal; font-style: normal;"><span><span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span><img alt="PastedGraphic-2.png" src="cid:0499780D-53E4-4E39-BF65-37F7D6FC29DD@cfa.harvard.edu" width="263"></span><meta charset="UTF-8"><span style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;"><br class="Apple-interchange-newline"><span style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); font-family: Monaco; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; 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