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Hi folks - This is meant to be a longer case study, or example, of how you might actually
use the IRSA FinderChart tool. So, my real science case is that I have a bunch of objects
that I've selected based on WISE colors to think that they might be legitimately young
stars. And, I want to go look at all the images that I can find in FinderChart to see if the
objects actually look like point sources, or if they might be background galaxies instead.
So, I have over here an IPAC table format, that's what the FinderChart tool needs for
an upload. It's actually just a plain ASCII file, but sometimes there are some structures
of the file that might be difficult to get right on the first time. So, if you get it
close to the IPAC table format that you want, you can actually go and find the IRSA table
validator by Googling "IRSA Table Validator". And you get the "Table Reformat and Validation
Service." So, if you get your IPAC table close to what you want, you can go over here and
pick the file, and upload it. And, it will go and give you a completely valid file in
IPAC table format. So, we're going to save it as an ASCII, dot-tbl, format. And, then
go back over to FinderChart. Now, this is a bug, which we anticipate fixing eventually,
if you go and load the IPAC table format that came out of the table format and validation
service, at the moment, it doesn't actually work in FinderChart. And, it's because FinderChart
is expecting a lower case "ra" and a lower case "dec". So, if we make that change, save
the file, and go back over to FinderChart. Go to multi-object search, and find the file
that we just edited. The default 300 arcseconds is fine, the display size is fine. I want
all available relatively high resolution imaging, so that's what I want, and I don't need IRAS.
I'm going to go and search. And it's going to take a couple seconds to render. Over here
on the left, is a list of all the targets that we have entered. And, over here on the
right is all the images that it finds. So, if I want to see more of the columns that
I entered, I can change the size of this. Note that it didn't like my header of "IAUname",
it was expecting "obj name", so let's go over here and change this to "object name", save
it, go back over to searches, and enter the file again. ASCII table. ANd then it will
go and it has the object name entered into the table. So, now over here on the right
hand side, I have all of the images that it found for each one of the targets that I've
entered. So, over here on the right hand side, I can scroll through the list, click on individual
rows, and it will update the images on the right to reflect the images that it found
for each one of the objects. Sometimes, it takes a little while to render, and you might
get that kind of thing in the browser; just give it a second and it will fix itself. So,
over here, we have all the images it returned. So, in this particular case, this particular
object has the right WISE colors to be a young star, but if we go down here to the WISE images,
it looks like a point source, but it's got sort of a peanut-shaped source here, which
may be contributing to the flux from this object. So, in this fashion, we can scroll
through this entire list, and look at the objects that are returned. In this case, in
DSS, it looks like this might be a binary that's unresolved at the longer bands. You
can scroll through the list and make notes as you go along as to whether or not you believe
that these objects are legitimately point sources. You can see by the different name
here that I have a ringer in the list, so let's click on this. We go and get the images
for this object. You can see that it's kind of faint at DSS images and it might be resolved.
If I let my mouse hover over the target, if I look at the upper right hand side, you can
see a zoom-in, and that may not be a point source. Let's zoom in on all of these images
at once. Go and get the toolbox, and zoom the image in, and note that it's zooming in
on all of the images simultaneously. And we're going to have it center up the image on the
target. And, there it is. It does not look like it's a point source. You get to Sloan,
and sure enough, it is definitely not a point source. Even though it might be a point source
at WISE bands and 2MASS, it doesn't look like it's a point source in Sloan. So, this one
actually turns out to be an edge-on galaxy. So we're going to drop this from our list
of potential YSO candidates. If I want to download all of the data, I can choose 'prepare
download'. If I want to have the FITS files saved to disk, or the HTML files, or the PDF
or PNG files saved to disk, I can 'prepare download' that way. But, I find it pretty
easy to interact with the service in this fashion, and then scroll through the targets
on the left, and look at each one of the images that is returned on the right hand side. And
then keep notes in a file elsewhere on my desktop of which objects I want to keep and
which objects I might want to drop.