------------------------------------------------------------------------ Chandra X-ray Center (CXC) ------------------------------------------------------------------------ The Great Observatory quartet of missions -- Hubble Space Telescope (launched 1990) Compton Gamma-ray Observatory (1991) Chandra X-ray Observatory (1999) Spitzer Space Telescope (2003) -- had a major impact on astronomy. Chandra built on the success of Einstein (grazing incidence) and was both an imaging and spectroscopic mission. It remains the highest angular resolution mission at X-ray bands with no successor in sight (in this regard). Programs: $ csChandra .. cone search $ wsCXO ... weekly status of the Chandra X-ray Observatory ------------------------------------------------------------------------ Simple cone search ------------------------------------------------------------------------ CXC provides a convenient command line interface (CLI) to the holdings of the Chandra data base https://cxc.cfa.harvard.edu/csc/cli/index.html This is, by far the simplest and most useful, query and, like all respectable data archives, CXC hosts this tool. The base URL is http://cda.cfa.harvard.edu/csc2scs/coneSearch and an example is $ curl "http://cda.cfa.harvard.edu/csc2scs/coneSearch?RA=$RA&DEC=$DEC&SR=$SR&VERB=2" -o out.vot where $RA, $DEC, SR are in decimal degrees and VERB=1,[2],3 (see Appendix I) and the ouput is a VO table. I have written a Unix wrapper to this call and also a decoder to convert the VO Table to a csv file. My program also, on request, produces, a header file. ------------------------------------------------------------------------ Weekly status of Chandra X-ray Observatory ------------------------------------------------------------------------ Curious to know what CXO has been doing for this week? $ wsCXO ------------------------------------------------------------------------ Appendix I: Cone Search ------------------------------------------------------------------------ REFERENCE: http://cda.cfa.harvard.edu/cscvo/ RA - Right Ascension in decimal degrees DEC - Declination in decimal degrees SR - Search Radius in decimal degrees VERB -Verbosity of the result set. Defaults to 2. The following values are allowed: verbosity = 1 reports the source name, ra and dec values from the master source table for each matching source resulting from the cone search - verbosity = 2 reports the master source summary results (the default verbosity level) - verbosity = 3 reports all the columns in the master source table 1 - Reports the source name, ra and dec values from the master source table for each matching source resulting from the cone search 2 - Reports the following properties from the master source table: m.name, m.ra, m.dec, m.err_ellipse_r0, m.conf_flag, m.sat_src_flag, m.significance, m.flux_aper_b, m.flux_aper_lolim_b, m.flux_aper_hilim_b, m.flux_aper_w, m.flux_aper_lolim_w, m.flux_aper_hilim_w, m.extent_flag, m.hard_hm, m.hard_hm_lolim, m.hard_hm_hilim, m.hard_ms, m.hard_ms_lolim, m.hard_ms_hilim, m.var_intra_index_b, m.var_inter_index_b, m.var_intra_index_w, and m.var_inter_index_w 3 - Reports all master source properties ------------------------------------------------------------------------ VOTable ------------------------------------------------------------------------