------------------------------------------------------------------------ WISE photometry ------------------------------------------------------------------------ WISE was a MIDEX mission (PI: Ned Wright) and mapped the sky at 3.4 (W1), 4.6 (W2), 12 (W3) and 22 (W4) microns with angular resolution of [6.1,6.4,6.5,12] arc-seconds and 5sigma sensitivity of [0.08,0.11,1,6] mJy in clean regions. The sensitivity improves towards the ecliptic plane owing to the scanning pattern (and also lower zodiacal light). The WISE catalog has 563 million entries. WISE photometry is the same as that for Spitzer (Vega!, groan). ----------------------------------------------- Band lambad(micron) Flux(Jy) AB_mag ----------------------------------------------- W1 3.4 310 2.699 W2 4.6 172 3.339 W3 12 31.7 5.174 W4 22 8.4 6.620 ----------------------------------------------- To convert WISE Vega mag to the AM system: add the above offset to the reported WISE mags. ------------------------------------------------------------------------ I. Retrieving WISE photometry for objects found in a search of the cone ------------------------------------------------------------------------ We seek to build a Unix bash script which returns W1-W4 photometry (and associated errors) for a given RA, DEC and cone radius. We will make use of "application programming interface" (API) that IPAC, as with any fine data establishment, provides with. Following a bit of nosing of IPAC/IRSA around I found a few simple examples of API calls. API calls are made to curl (or wget) and consist of a SINGLE line. Below I display an example API (from IRSA tutorial) but have split the call into several lines. If you want to test it you need to "rejoin" the lines into a single line. The call below seeks WISE objects at RA=00h42m44.32s DEC=41d16m08.5s and cone search radius of 300 arc-seconds. It ouputs an an ASCII table (instead of some god-awful VO or XML output). By studying this call you can figure out how to make a simple API call. Note that anything inside a [...] is the default value. The bit that is complicated is "selcols" (for select columns). This feature essentially selects which columns should be sent to the output. You need to know the names of the columns in the data base. $ curl -o search_results.tbl "https://irsa.ipac.caltech.edu/cgi-bin/Gator/nph-query? catalog=allwise_p3as_psd& spatial=cone& radius=300& radunits=arcsec& objstr=00h+42m+44.32s+41d+16m+08.5s& size=300& outfmt=1& selcols=ra,dec,w1mpro,w2mpro,w3mpro,w4mpro" Notes: catalog = allwise_p3as_psd (AllWISE) neowiser_p1bs_psd (NEOWISE) spatial = cone,box,polygon,Upload, None=All-sky searrch radius = radius of cone search [10 arsec] radunits = units of cone search: arcsec,arcmin,deg [arcsec]) objstr = target_name or coordinates of search center selcol = select columns for output (need to know names of columns) outfmt = 0:HTML,1:ASCII,2:SVC,3:VO,6:XML [0] ------------------------------------------------------------------------ II. A simple bash API script to retrieve WISE photometry ------------------------------------------------------------------------ See attached program "photWISE" ------------------------------------------------------------------------ III. Usage ------------------------------------------------------------------------ $ photWISE 20h43m19.03s +44d38m20.4 5 c \ORIGIN = 'IPAC Infrared Science Archive (IRSA), Caltech/JPL' \DATETIME= '2020-11-24 17:19:00' \DataTag = 'ADS/IRSA.Gator#2020/1124/171900_9705' \DATABASE= 'AllWISE Source Catalog (allwise_p3as_psd)' \EQUINOX = 'J2000' \SKYAREA = 'within 5 arcsec of ra=310.82929 dec=+44.63900 Eq J2000 ' \StatusFile = '/workspace/TMP_YTzQ1S_9705/Gator/irsa/9705/log.9705.html' \SQL = 'WHERE (no constraints) \SQL = 'SELECT (12 column names follow in next row.)' | ra| dec| clon| clat| w1mpro| w1snr| w2mpro| w2snr| w3mpro| w3snr| w4mpro| w4snr| dist| angle| 310.8277422 44.6389351 20h43m18.66s 44d38m20.17s 10.868 47.3 10.724 51.5 10.326 10.2 8.905 2.6 3.971682 266.628089 $ photWISE 20h43m19.03s +44d38m20.4 number of sources 1 | ra| dec| clon| clat| w1mpro| w1snr| w2mpro| w2snr| w3mpro| w3snr| w4mpro| w4snr| dist| angle| 310.8277422 44.6389351 20h43m18.66s 44d38m20.17s 10.868 47.3 10.724 51.5 10.326 10.2 8.905 2.6 3.971682 266.628089