Introduction of JVO- how to use the JVO for your science study Yuji Shirasaki,
Masahiro Tanaka,
Satoshi Kawanomoto
NAOJ ADAC

Contents
1. What is VO ? Why do we need a VO ?
2. Current status of JVO project
3. JVO demo (Data Search, Science use case)
4. The other VO projects
5. VO compliant application–––

Aladin (Image Viewer)
SpecView (Spectrum Viewer) S. Kawanomoto
TopCat (Catalog Table Viewer) M. Tanaka

What is VO ?
VO is a collection of astronomical data archives andanalysis tools that can be federated throughcomputer networks to create an environment inwhich research can be conducted.
Real Observatory
Sky

Virtual Observatory
Databases all over the world

Telescope
InstrumentInternet
Desktop Computer

Astronomical Data

Astronomical Data

As the databases can be accessed through the standard
interface, they are easily integrated with the astronomical
analysis tools.

Why do we need VO• Classical astronomy was done by using one
telescope of one organization.
• Many of modern astronomy has been done by using
several telescopes of various organizations.
Data

ComputingStorageOrganization A

Organization C
Organization B

Problem in the classical system
1. User must access to the individual sites.
2. Query interface is different for each sites.
Difficult for programming.
3. There is no reliable way to find a URL whereastronomical data is provided.
4. There is no established procedure to publish yourdata to the astronomical community.
VO provides a framework for solving these problem:• Standards on resource metadata management  (3,4)• Standards on data access interface  (1,2)

Modern system in the VO framework
SearchableRegistry
Service Metadata② harvest metadata
Service Metadata① register services
ComputingServicePublishing
Registry③ discover a service
VOStorage ServiceData Service

hetot
cessca④ceservi⑤ store the dataVO solve all the problem ?
1.

No !

Raw data reduction is still an obstacle for mostof the researchers who are not familiar with
the instrument.
2. Data quality control is crucial forinterpretation of the data.
3. Observatory is the only competent to manage
these issues.
4. Closer collaboration between VO project andobservatory is crucial for establishing anenvironment where astronomical research canbe conducted efficiently.

IVOA

International Virtual Observatory
Alliance (IVOA)• 16 countries and organizations• Standardization of data exchange format, data
access interface …
• Development of VO software• Discussion on a mailing list
• Interoperability meeting(twice per year)• 10 Working Groups• 8 Interest Groups
http://www.ivoa.net/

Interconnected VOs in the World

JVO

JVO collaborators
Project Scientists
NAOJ• Mizumoto• Ohishi• Oe• Shirasaki• Tanaka• Honda• Kawanomoto
ICRR• Yasuda
Ochanomizu U.
• Masunaga

System EngineersFujitsu Ltd.
• Monzen• Kawarai• Ishihara• Tsutumi

SEC Ltd.
• Morita• Nakamoto• Kobayashi• SakamotoSupporterNII• MiuraCurrent JVO activity• Development of software using the VO standard– VO portal service– VO data service development toolkit– Data analysis web service• VO data service– SXDS data service– Subaru Suprime-Cam image data service– SDSS, 2MASS …

• VO enabled science– Cosmic string search– QSO-Galaxy clustering study– More coming …

JVO Prototype 3DemoLoginOpen LDAP* authentication* open source implementation ofthe Lightweight Directory Access Protocol.

Data Search Page
Specify a databaseObject nameresolverSpecify a searchregionInput SQL

Execute QueryData Search Status Page

Current Query

Query Result

VOTable Viewer
Download FITS file

Quick Look of the FITS image
URL to retrieve the FITS data

Registry

Key word search

Get service metadatafrom the publishingregistries
Get all the dataservices

Registry Search Result

Registry Search Result Bottom

80 VO resources are available on JVO
portalScience Use Case 1
Cosmic String SearchCosmic String• GUT theory predicts the production of a cosmic
string at very early universe t ~ 10-35 s,• Width < 10-22m,• Length ~ size of theUniverse.
• Mass of 10 km string~ the Earth
Deep Wide field image:Subaru/Suprim-Cam
Wide field Survey: SDSS

http://www.damtp.cam.ac.uk/user/gr/public/cs_evol.html

Search for Gravitational Lenses
produced (?) by Cosmic Strings• SXDS data observed by Subaru• Results were obtained less than 5 min,displaying SEDs
• It has been proventhat VO canaccelerate
researches.

Cosmic String Search Result

Science Use Case 2
QSO/Galaxy
Clustering StudyQSO & Galaxies clustering study– Origin of the large scale structure• QSO is a tracer of high density regions in theuniverse  hierarchical clustering model• Comparison between the observation andtheoretical prediction is required.
– Origin of the QSO activity• Why is the QSO so powerful.

• Test of the galaxy merger modelWorkflow for studying the QSO/Galaxyclustering
1. Select QSO coordinates from the QSO catalog Query to the Skynode Catalog Database.
2. Search deep imaging data which covers the QSOregions  Query to the Skynode of Subaru ImageDatabase
3. Create catalog from the imaging data  Invoke theSExtractor Web service.
4. Estimate the distance to the objects around the QSO
 Invoke the HyperZ Web service
5. Try Clustering Analysis  Invoke the clustering analysis
web service.

QSO-Galaxy Search

QSO Search PlotPhotometric Redshift

NVO
DataScope

NVO
Open SkyQueryComparison among the major VO
portals
JVO Portal DataScope
Catalog
Image
Spectrum
Cross Match

StorageAnalysis

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X
XX

OpenSkyQuery○X
X○○X

Road map of the JVO
2005
DevelopmentOperation

200620072008database federation
workflow system
single sign-on
user’s storage
open to therestricted persons
open to the public
introduce workflow system

Open
Softwarea data service toolkit is released twice every year