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ADC Scientific User's Guide

Here we provide a sampling of specific scientific user scenarios to guide you through ADC's suite of data services. The ADC data holdings contain a wealth of astronomical information, while the ADC Data Viewer, CatsEye, IMPReSS, Quick Reference Pages ADC service can be employed to complete the sample user request. In those cases, we rank the different available search strategies in this order of increasing usefulness: Good -> Better -> BEST.

User Scenarios:

Where can I find multi-wavelength data on galaxies?
Where can I find data on AR Lac (or any other specific astronomical object)?
What NASA missions have obtained data on my chosen targets?
What NASA missions have obtained data in a given region of the sky?
Which database tool allows me to select, sort, and manipulate the tabular data in astronomical catalogs?
How do I find the most extreme objects in an ADC catalog list.
How do I plot table values and look for correlations among the tabulated data in astronomical catalogs?
How do I compare the RA-Dec distribution of Abell (1958) Rich Clusters of Galaxies with the RA-Dec distribution of Arp (1966) Peculiar Galaxies?
What are the most frequently accessed catalogs at the ADC?
How do I find the Hewitt & Burbidge Quasar Catalog?
How do I find data on Cepheid variable stars?
What is the ACT Catalog?
What is the RASS Catalog?
How do I find specific measurements of flux versus wavelength for standard stars?
Where can I find lists of Clusters of Galaxies for my Chandra observing proposal?

User Scenario	ADC Search Strategies
Where can I find multi-wavelength data on galaxies? [`Return to Top of Page`]	NOTE: If you have a list of specific target names or target coordinates, then use the ADC data archive search tool IMPReSS to query all NASA astrophysics mission archives for observations around a user-selected sky position. Catalog Class Query. Select "Galaxies" (or a more restricted class of objects) under the Classes menu and select the desired wavelength domains under the Attributes menu. Then push Query Knowledge Base. BEST: When you know the scientific category, go to the list of ADC Quick Reference Pages. In this case, select Basic Data on Galaxies. A selection of relevant catalogs can be found within the quick reference list under Wavelength-Selected Catalogs, also under Spectral Atlases & Spectrophotometry, and also under Photometry & Fluxes. ONE POSSIBLE ANSWER: Condon (1995) Extragalactic IRAS sources: optical+IR+radio data.
Where can I find data on AR Lac (or any other specific astronomical object)? [`Return to Top of Page`]	NOTE #1: The ADC is primarily a provider of astronomical catalogs and data tables, and it is not intended to replace the target-specific archive functions of the NASA Extragalactic Database (NED) or of SIMBAD. NOTE #2: The ADC does provide a comprehensive data archive search tool IMPReSS to query all NASA astrophysics mission archives for observations around a user-selected sky position. If you are looking for derived catalog data, try one of these strategies (example below is to search for AR Lac among catalogued table data): Good: If you know the type of object that you are searching, go to the ADC Data Search Form. Type some scientifically specific words in the Catalog Description search box (e.g. "eclipsing binaries"). Then Submit. Scan the resulting list of catalogs for AR Lac data. Better: If you know the type of object that you are searching, go to the VizieR Service at ADC. Enter the VizieR service and type "eclipsing binaries" in the name/word search box. Then Submit. Select catalogs from among the resulting list. Then Continue with selected Catalogues. Select the data tables to search, and Continue. Enter AR Lac (or other target name or target coordinate) in the Search by Position form. Submit Query to obtain search results for your selected target. BEST #1: Use the Object Name Search capability available at the Astrophysics Data System (ADS) Abstract Service. Enter "AR Lac", then Send Query. BEST #2: Use the Object Name Search capabilities at NED (for extragalactic objects) or at SIMBAD (for stellar objects). Enter "AR Lac", then Submit. ONE POSSIBLE ANSWER: Catalog # 5075 -- Parameters of Binary Stars.
What NASA missions have obtained data on my chosen targets? What NASA missions have obtained data in a given region of the sky? To query all NASA astrophysics mission archives --->> [`Return to Top of Page`]	Traditional method: Go to the various NASA data archive sites and query their database for the selected target (e.g., ADC, HEASARC, HST/STScI, IPAC, NSSDC, or SAO/Chandra. BEST: Use the IMPReSS service to generate a sky map of observation locations (i.e., perimeters of observation fields-of-view) in a region around a user-specified coordinate location. Follow these steps: Enter the coordinates or the name of the object on the IMPReSS Input Form. Then Submit. A Web Frames version is available. An On-Line IMPReSS Tutorial is available.
Which database tool allows me to select, sort, and manipulate the tabular data in astronomical catalogs? [`Return to Top of Page`]	Use the ADC Catalog Viewer to browse, sort, and visualize the data in ADC catalogs or journal tables. Follow these steps: Select a Catalog ID or Search the ADC or Browse the ADC Holdings. Then Go to the selected catalog. Select a table file from among the files representing that catalog holding -- to visualize the data. Specify the fields that you wish to browse, and also (if you choose to override the default range values) specify your desired ranges in the values for the table fields. Create Table to browse the file contents. Return to previous Web page to re-select the table fields and to fine-tune the ranges of tabulated values to browse. Sort the table listing by pressing either the << (descending sort) or >> (ascending sort) buttons on the ADC Viewer results screen. You may plot the data in your culled & sorted table (or in any ADC catalog) using the CatsEye tool. Push the [Plot] button on the ADC Viewer results screen to activate CatsEye. An On-Line Data Viewer Tutorial is available.
How do I find the most extreme objects in an ADC catalog list. [`Return to Top of Page`]	STRATEGY #1: Follow the instructions given above on how to use the ADC Catalog Viewer to browse and sort the data in ADC catalogs or journal tables. Sort the table listing by pressing either the << (descending sort) or >> (ascending sort) buttons on the ADC Viewer results screen. The table can be sorted on any column (field) and then browsed to find those catalog objects having the most extreme values for the selected column. STRATEGY #2: Use the CatsEye tool to plot any two numerical parameters from an ADC catalog in an X-Y scatter plot. Then examine the scatter plots for extreme values, outliers, or other unusual points. Push the [Plot] button on the ADC Viewer results screen to activate CatsEye. Click on any point in the CatsEye plot to retrieve the catalog line listing for that data point directly from the corresponding ADC catalog/table. [The Selected data point information appears in the bottom right frame of the CatsEye screen.] After selecting a point in the plot, click on the "N" link at the bottom of the CatsEye screen in order to query for NED results on the object. Alternatively, after selecting a point in the CatsEye plot, click on the "I" link at the bottom of the CatsEye screen in order to query for IMPReSS database for all NASA mission observations obtained for that object. An On-Line CatsEye Tutorial is available.
How do I plot table values and look for correlations among the tabulated data in astronomical catalogs? [`Return to Top of Page`]	Follow the STRATEGY #2 instructions given in the example above, which describes how to use the CatsEye tool to generate scatter/correlation plots for any ADC catalog or journal table. CatsEye is activated by pushing the [Plot] button on the ADC Catalog Viewer results screen.
How do I compare the RA-Dec distribution of Abell (1958) Rich Clusters of Galaxies with the RA-Dec distribution of Arp (1966) Peculiar Galaxies? [`Return to Top of Page`]	NOTE: The following long list of steps will guide you step-by-step through the process of using CatsEye to create X-Y scatter plots from one ADC catalog and then using CatsEye again to overplot a second X-Y scatter plot from another ADC catalog. The choice of abscissa and ordinate in CatsEye plots is entirely user-selectable. We use RA-Dec in this example only as an illustration of the capability of the tool. Use the Clusters of Galaxies Quick Reference Page to find the Abell (1958) Catalog of Rich Clusters of Galaxies. Follow the instructions given earlier to use the ADC Catalog Viewer to select the abell.dat Abell catalog file. Select an interesting range of RA and Dec (e.g., 0h < RA < 6h and +0 < Dec < +45). After narrowing the Abell galaxy cluster catalog listing to the desired RA/Dec range, select the "Rename Table" File Action on the "Your Tables / Action" pull-down menus found on the ADC Viewer results screen, to rename your culled table (e.g., myAbell.dat). The last step stores the Abell catalog data for later comparison with the Arp catalog data. Now go back to the ADC Science Data page to find the next catalog. Go to the Galaxies Quick Reference Page to find the Arp (1966) Atlas of Peculiar Galaxies. Follow the instructions given earlier to use the ADC Catalog Viewer to select the table2 Arp Atlas catalog file. Select the same range of RA and Dec as previously selected for the Abell catalog (i.e., 0h < RA < 6h and +0 < Dec < +45). After narrowing the Arp peculiar galaxy catalog listing to the desired RA/Dec range, select the "Rename Table" File Action on the "Your Tables / Action" pull-down menus found on the ADC Viewer results screen, to rename your culled table (e.g., myArp.dat). Use the CatsEye tool to plot the data from the two selected ADC catalogs in an X-Y scatter plot. Your created table files should appear in the left-hand frame of the CatsEye screen. For each file (e.g., myAbell.dat and myArp.dat), click the Plot this table? button. Then use the pull-down menus to choose "RA" for "X" and "Dec" for "Y" for each catalog. Chose a different plot Symbol for each catalog file. Make Plot to see the results. The plot can be scaled using the selections in the CatsEye Plot frame. Interesting data points can be clicked in the CatsEye Plot frame, causing the line(s) from the chosen catalogs for the selected (clicked) data points to appear in the frame at the bottom of the CatsEye screen. Instructions were given earlier on how to follow the "N" and "I" links given in the Selected data point information area (bottom frame) to access the NED and IMPReSS services, respectively, for the selected catalog object.
What are the most frequently accessed catalogs at the ADC? [`Return to Top of Page`]	Examine the List of Most Popular ADC Catalogs.
How do I find the Hewitt & Burbidge Quasar Catalog? [`Return to Top of Page`]	Good: Go to the ADC Data Search Form. Enter a search parameter (e.g., catalog description = "Quasar" or author = "Hewitt" or author = "Burbidge"). Then Submit. Better: When you know the scientific category, go to the list of ADC Quick Reference Pages. In this case, select Quasars & AGN. The desired catalog can be found within the quick reference list under General Catalogs of Quasars. BEST: When you know the author's name, go to the ADC Author Index and select H for "Hewitt". ANSWER: Catalog # 7158.
How do I find data on Cepheid variable stars? [`Return to Top of Page`]	Good: Use the ADC Keyword Index and select S for "Stars". Search the "S" keyword index listing for the word "Cepheid". Better: When you know the scientific category, go to the list of ADC Quick Reference Pages. In this case, select Variable Stars. A selection of relevant catalogs can be found within the quick reference list under Pulsating Variables. BEST #1: Go to the ADC Data Search Form. Type "Cepheid" in the Catalog Description search box. Then Submit. BEST #2: Go to the VizieR Service at ADC. Enter the VizieR service and type "Cepheid" in the name/word search box. Then Submit. ONE POSSIBLE ANSWER: HST Extragalactic Distance Scale Key Project - M101 Cepheids database.
What is the ACT Catalog? [`Return to Top of Page`]	Good: Go to the ADC Data Search Form. Type "ACT" in the Catalog Description search box. Then Submit. Better: Go to the VizieR Service at ADC. Enter the VizieR service and type "ACT" in the catalogue abbreviation search box. Then Submit Query. BEST: Go to the list of ADC Quick Reference Pages. In this case, select Common Catalog Names. Search the listing under the letter "A" for the catalog abbreviation "ACT". ANSWER: Catalog # 1246 -- the Astrographic Catalogue and Tycho combined catalogs.
What is the RASS Catalog? [`Return to Top of Page`]	Good: Go to the ADC Data Search Form. Type "RASS" in the Catalog Description search box. Then Submit. Better: Go to the VizieR Service at ADC. Enter the VizieR service and type "RASS" in the name/word search box. Then Submit. BEST: Go to the list of ADC Quick Reference Pages. In this case, select Common Catalog Names. Search the listing under the letter "R" for the catalog abbreviation "RASS". ANSWER: Catalog # 9010 -- the ROSAT All-Sky Survey.
How do I find specific measurements of flux versus wavelength for standard stars? [`Return to Top of Page`]	Good: Go to the ADC Data Search Form. Enter a selection of scientifically specific search parameters (e.g., catalog description = "atlas stellar spectra"). Then Submit. Better: Go to the VizieR Service at ADC. Enter the VizieR service and select "Spectrophotometry" in the keyword selection menu. Then Submit. BEST: When you know the scientific category, go to the list of ADC Quick Reference Pages. In this case, select Basic Stellar Data. A selection of relevant catalogs can be found within the quick reference list under Spectral Atlases and also under Photometry/Spectrophotometry. ONE POSSIBLE ANSWER: Pickles (1998) Stellar Spectral Flux Library.
Where can I find lists of Clusters of Galaxies for my Chandra observing proposal? [`Return to Top of Page`]	BEST: When you know the scientific category, go to the list of ADC Quick Reference Pages. In this case, select Basic Data on Galaxy Groups and Clusters. A wide selection of catalogs can be found there. Select the desired type of galaxy clusters and find lists of catalogs under that selection. ONE POSSIBLE ANSWER: Catalog # 7110A -- Abell, Corwin, & Olowin (1989) Catalog of Rich Clusters of Galaxies.

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Revised: Tuesday, 26-Jun-2007 14:34:14 EDT