Reddening and Extinction maps of the Magellanic Clouds 2009-06-02T08:42:00Z 200 A catalogue of E(V-I) extinction values is presented for 3174 (LMC) and 693 (SMC) fields within the Magellanic Clouds. The extinction values were computed by determining the (V-I) colour difference of the red clump from Optical Gravitational Microlensing Experiment (OGLE III) observations in the V and I bands and theoretical values for unreddend red clump colours. 10.21938/AvlnaD4AvIeK9nIscpF.YA `_) shows the laws adopted to compute extinction values in the various bands: ========== ==== ======= ====== ======== ======== Filter name |λ_eff| A/A(V) A/E(B-V) A/E(V-I) ========== ==== ======= ====== ======== ======== Landolt U 3372 1.66 5.43 3.94 Landolt B 4404 1.32 4.32 3.13 Landolt V 5428 1.02 3.32 2.4 Landolt R 6509 0.82 2.67 1.94 Landolt I 8090 0.59 1.94 1.41 Gunn g 5244 1.07 3.48 2.52 Gunn r 6707 0.79 2.59 1.88 Gunn i 7985 0.61 1.99 1.44 Gunn z 9055 0.47 1.54 1.12 Stromgren u 3502 1.6 5.23 3.79 Stromgren b 4676 1.24 4.05 2.93 Stromgren v 4127 1.39 4.55 3.3 Stromgren beta 4861 1.18 3.86 2.8 Stromgren y 5479 1 3.28 2.37 Sloan u' 3546 1.58 5.16 3.74 Sloan g' 4925 1.16 3.79 2.75 Sloan r' 6335 0.84 2.75 1.99 Sloan i' 7799 0.64 2.09 1.51 Sloan z' 9294 0.45 1.48 1.07 ========== ==== ======= ====== ======== ======== Crossmatching with your tables ------------------------------ If you want to add extinctions to your own tables, use TAP. Our TAP server has the ivo-id ivo://org.gavo.dc/__system__/tap/run. You will need a TAP client to do this. Recent versions of `TOPCAT `_, for example, allow you use TAP. To add a column with the reddening, load the table into TOPCAT and note its id (that's the number in front of the colon in the Table List in TOPCAT's main window; if you've just started TOPCAT, that's 1). Then, select TAP from the TOPCAT's VO menu, at the bottom ("TAP URL") enter ``http://dc.g-vo.org/tap`` and click "Enter Query". In the resulting dialog, enter:: SELECT ev_i, mine.* FROM mcextinct.exts AS exts JOIN tap_upload.t1 AS mine ON (1=CONTAINS(POINT('ICRS', mine.raj2000, mine.dej2000),exts.bbox)) If your table has id 15, say, change ``tap_upload.t1`` to ``tap_upload.t15``. You will also need to fix the column names for RA and Dec (written as raj2000 and dej2000 here). To compute extinctions in specific bands, use the factors given in the A/E(V-I) column in the table above above. To, e.g., add the extinctions in Sloan u' and Sloan z', say:: SELECT ev_i*3.74 as A_sloan_u, ev_i*1.07 as A_sloan_z, mine.* FROM mcextinct.exts AS exts JOIN tap_upload.t1 AS mine ON (1=CONTAINS(POINT('ICRS', mine.raj2000, mine.dej2000),exts.bbox)) For batch processing, similar operations can be done with `STILTS `_ or GAVO's `tapsh `_. For the latter, you could use a shell script like the following to add an ev_i column to the file named in the first command line argument argument (note the backup); again, you'll need to fix the column names for RA and Dec:: #!/bin/sh cp $1 $1.bak tapsh < `_ The photometric data of the red clump is provided by the OGLE collaboration. Part of this research was supported by SFB 881 "The Milky Way System". ]]> creator.name:Haschke, R. creator: creator.name: Grebel, E.K. creator.name.altIdentifier: orcid:0000-0002-1891-3794 creator: creator.name: Duffau, S. large-magellanic-cloud interstellar-extinction interstellar-dust Optical Infrared 0.02 2011AJ....141..158H label, name, factor, verb Landolt U, a_U, 3.94, 10 Landolt B, a_B, 3.13, 10 Landolt V, a_V, 2.4, 10 Landolt R, a_R, 1.94, 10 Landolt I, a_I, 1.41, 10 Gunn g, a_gg, 2.52, 21 Gunn r, a_gr, 1.88, 21 Gunn i, a_gi, 1.44, 21 Gunn z, a_gz, 1.12, 21 Stromgren u, a_su, 3.79, 25 Stromgren b, a_sb, 2.93, 25 Stromgren v, a_sv, 3.3, 25 Stromgren beta, a_sbeta, 2.8, 25 Stromgren y, a_sy, 2.37, 25 Sloan u', a_slu, 3.74, 15 Sloan g', a_slg, 2.75, 15 Sloan r', a_slr, 1.99, 15 Sloan i', a_sli, 1.51, 15 Sloan z', a_slz, 1.07, 15 //scs#pgs-pos-index Extinction values within certain areas in the Magellanic clouds. PositionInterval ICRS [bbox]Position ICRS "centerAlpha" "centerDelta" 4/2068 5/8263,8268-8269,8271,8280,8323,8326,8329,9376,9378 6/33045-33047,33049,33051,33069,33080-33081,33083,33104-33106,33112,33124-33126,33128-33130,33287,33289,33291,33297-33299,33313,33315,33323-33326,33328-33330,37416,37418,37536 1.986e-19 6.02e-19 raMin, raMax, decMin, decMax, ev_i, sig_ev_i float(@raMin) float(@raMax) float(@decMin) float(@decMax) SELECT u.ra, u.dec, e.ev_i, FROM uploadedPos AS u JOIN mcextinct.exts AS e ON (spoint(u.ra, u.dec) @ e.bbox) MC Exinctions by Positions **Do not use this service.** We will soon completely shut it down, since it is no longer necessary and actually far more cumbersome than the TAP-based procedure for doing what this service did. See the \RSTservicelink{mcextinct/q/info}{Service Info} for how to add extinction columns to your tables. Enter positions within the LMC to obtain the extinction values. Note that no values will be returned for positions we do not have extinction values for. If you have VOTable data, the \RSTservicelink{/cross/q/match/form}{crossmatch service} with a sufficiently large search radius might work better for you. '" " && bbox")%( base.getSQLKey("RA", inPars["RA"], outPars), base.getSQLKey("DEC", inPars["DEC"], outPars), base.getSQLKey("SR", inPars["SR"], outPars)) ]]> True `_. To find out how the extinctions for the various bands are computed, please refer to the `service info `_ . If you want to compute extinctions for your object lists, see the service info's `crossmatching with your tables`_ chapter. .. _crossmatching with your tables: /mcextinct/q/cone/info#crossmatching-with-your-tables ]]> 93.5257 -72.8005 MC extinctions Magellanic Clouds Extinction Values Sorry, your coordinates are outside of the area of the Clouds covered by OGLE-III \name cone/availability true", "upSince>20") ]]> cone/availability self.assertValidatesXSD() cone/capabilities GET cone/capabilities self.assertValidatesXSD() cone/tableMetadata mcextinctcenteralpha cone/tableMetadata self.assertValidatesXSD() cone/form self.assertHasStrings("Matched: 12", "0.43", "Gunn g", # part of bounding box serialisation for 1487-297: # last and first digits "06 -69.2") cone/scs.xml 0.17', '84.62618', ' -69.24887') ]]> cone/scs.xml self.assertXpath("//v:FIELD[@ID='centerAlpha']", { "datatype": "double", "ucd": "POS_EQ_RA_MAIN"}) self.assertXpath("//v:FIELD[@ucd='ID_MAIN']", { "datatype": "char", "arraysize": "*"})