AgDurhamWorkshopJune06 Group C

Particpants

Nic Ross David Wake Tom Theuns John Helly Greg Davies

Problem Description

Results in VO lookout. Saved to myspace (Nic Ross). Loaded that into TopCat. Made G-R and R-I. Plotted against each other, galaxies in blue, stars in red.

Workflow builder, run. Set, drag into sequence. RA range in square brackets. 149.9 to 150.1. Dec from -0.1,0.1. Step, drag to sequence. Name: H, desc:search for objects in range. Others blank. Task Editor, Find: wfs,> merged object catalogue. Dec; ${dec[i]} ra same, format: votable, Radius: ${rad[i]}. Output: value= ivo;//uk.ac.le.star/NicRoss/... Move activity down. Drag for loop into sequence. Variable: i Items:[0,1]. Drag step into sequence. Set, Var:rad,value. Remove i from radius so only have one. Save to myspace, called WFS_workflow1. Green arrow to go. Look in VO Lookout window.

http://star-www.dur.ac.uk/~daw/astrogrid/ Dave's list of LRGs from SDSS. Aim: Look at wide-field survey around Sloan LRGs. Count all galaxies within a certain radius, measure environment, make a colour cut and count galaxies on the red sequence + measure their environment.

Filename of data in TopCat: SDSS_LRG_50k Select region (wide field survey?). Drag box over area of sky. Subset name: SDSS_LRG_10h15h Table, subset, apply subset.

New workflow. www.ast.cam.ac.uk/~eglez/ag/workflow.wf set var:SDSS_table value:SDSS_LRG_10h15h.vot

2nd Day

Following co-ordinates printed out: ra = 146.74412 dec = -0.65219

Could not get WFS objects within a 0.01 deg search radius. Problem appears to be in accessing WFS. WIll try SDSS instead.

Changed to accessing SDSS directly with url.

Script: SDSS Cone search url:

http://skyserver.sdss.org/vo/dr2cone/sdssconesearch.asmx/ConeSearch?ra=245.0&dec=41.&sr=0.1

Script:

source="http://skyserver.sdss.org/vo/dr2cone/sdssconesearch.asmx/ConeSearch?ra="+ra+"&dec="+dec+"&sr="+rad

table = astrogrid.tableHelper.builder.makeStarTable(source)

target = astrogrid.ioHelper.getExternalValue(userIvorn.toString()+"#votable/sdss_table.vot")

astrogrid.tableHelper.writeTable(target,table,"votable")

[Field1 r-i vs i] [Field1 g-r vs i] [Field6 g-r vs i] [Field6 r-i vs i]

Workshop Solution

Issues: Good and Bad

Good:

Very much liked TopCat and the ra/dec/z 3d projection of the SDSS LRGs.

Bad:

Would be good if workflow showed catalogue it was searching.

Turnaround time too long for editing scripts.

Information as to whether query has been successful or not can take a long time in coming.

Competing for time in the developers' queue.

Other Comments:

"I'm a natural" - C. Baugh (2006)

-- NicholasWalton - 12 Jun 2006