The SCUBA HAlf Degree Extragalactic Survey (SHADES) - III. I(17)

Determining an accurate position for a submm galaxy (SMG) is the crucial step that enables us to move from the basic properties of an SMG sample - source counts and 2-D clustering - to an assessment of their detailed, multi-wavelength properties, their con

Identi cationofsubmillimetregalaxiesintheSHADESSourceCatalogue

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APPENDIXA:POSTAGESTAMPIMAGES

Thissectionpresents25×25-arcsecpostagestampimagesofeachSMGintheSHADESSourceCatalogueaswellasadescriptionofthemostunusualexamples.

FigsA1andA2showgreyscaleR-bandopticaldataintheleft-handpanels,whereavailable,andgreyscale24-µmdataintheright-handpanels.SuperimposedontheR-bandimagesarehigh-resolution(1.3arcsecFWHMfortheLH,1.7arcsecFWHMforSXDF)radiocontours,plottedat 3,3,4...10,20...100×σ,whereσwasmeasuredinsource-freeregionsaroundeachSMGandisquotedinthelower-rightcornerofeachimageinunitsofµJybeam 1.Superimposedonthe24-µmdataarelow-resolution(4.2arcsec,FWHM)radiocontours,plottedat 3,3,4...10,20...100×σ,whereσwasmeasuredinsource-freeregionsaroundeachSMGandisagainquotedinthelower-rightcornerofeachimage.Brokencrossesmarkthepositionsofall24-µmsourcesbrighterthan150µJyfoundwithin15arcsecofSMGpositionsinSXDF–theirpositionsarelistedinTable4.Thelargecentralcirclesin-dicate2σpositionaluncertaintieswhereσ=0.6θ/SNRandde-boostedSNRvalueshavebeenadopted(Coppinetal.2006).Asshownin§4,thereisan86.5percentprobabilitythatthesecirclescontainthesourceofsubmmemission.Forcounterpartidenti ca-tionwesimplyusearadiusof8arcsec(or12.5arcsecfortheradio,15arcsecat24µm,tobemorecomplete).

Solidboxesindicaterobustidenti cations,whereP 0.05basedontheradioor24-µmcounts,oracombinationofthetwo.Dashedboxesindicatetentativeassociations.

Casesworthyofcomment

SomeoftheSMGspresentunusualcombinationsofobservedchar-acteristicsandwecommentonthemhere.

LOCK850.06:Betrayedatboth24µmand1.4GHz,butinvisibleoptically.

LOCK850.07:AsLOCK850.06,thoughwithanopticalcounter-partwithin1arcsec;possiblytypicalofthecompositeblue-redpairsnotedbyIvisonetal.(2002).

LOCK850.08:Anopticalcounterpartlikelyliesbehindthediffrac-tionspike.Anidealtargetforadaptive-optics-(AO-)assistedstud-ies,exploitingthebrightstartothenorth.

LOCK850.11:Thisapparentlyobvious24-µmidenti cationjustfailstoqualifyasa‘robust’counterpartbecauseitcomprisestwofaintersources.Weviewtheseaslikelycounterparts.Theyareco-incidentwithadisturbedopticalgalaxywhichshouldbetargetedspectroscopically.

LOCK850.14:Thenearestradioemitterdoesnotqualifyasaro-bustidenti cationbuthasanexcellentspectroscopicredshiftinthecatalogueofChapmanetal.(2005).

LOCK850.15:Acomplexsystemwithasmanyasthreeplausibleidenti cations,suggestiveofacolossalmerger.

LOCK850.16:DescribedindetailbyIvisonetal.(2002,2005).LOCK850.18:Anobvious–thoughfaint–radioidenti cation,yetthereisnosignof24-µmoropticalemission.

LOCK850.19:Astraightforward24-µmidenti cationwithsup-portfromfaintradioemission.

LOCK850.21:Asolid24-µmidenti cation;24-µmanddistortedopticalemissiontothesouth-eastmayberelatedphysically.

LOCK850.23:Faint24-µmandradioemissionpointtoafaintop-ticalcounterpart(circledinFig.A1);wellworthtargetingspectro-scopically,thoughnotformallyarobustidenti cation.

LOCK850.29:Faintradioand24-µmemissionyieldaformal

c0000RAS,MNRAS000,000–000identi cation;thedoubleopticalgalaxyseemstobeoffsettothe

northeastandyetitresemblesmanySMGs;itshouldbetargetedspectroscopically.

LOCK850.30:Amultipleradioidenti cation.TheweakestradiocomponentremainsstubbornlyaboveP=0.05;thebrightestra-dioemitterwasreportedbyIvisonetal.(2002)tohaveaninvertedradiospectrum(seeBertoldietal.2000forotherexamplesofthisphenomenon).The24-µmemissionappearstoliebetweenthera-diocomponents.Inoneobviousinterpretationtheradioemissionmayemanatefromlobespoweredbyacentral,blackhole-andstar-forminggalaxy.

LOCK850.34:Amultitudeofmultiplecounterparts.Anopportu-nityfordetailedstudyofapotentiallycomplex,interactingsystem.LOCK850.37:Robustbutdistinctidenti cationsat24µmand1.4GHz.Challenging,optically.

LOCK850.48:Aseeminglystraightforwardidenti cation,yetapotentiallycomplexsystem.

LOCK850.52:Anextendedcounterpartat24µm,barelyvisibleinthehigh-resolutionradioimageandyetobviousandextendedinthelower-resolutionmap;extraresolutionavailableintheLHhasclearlyhinderedtheidenti cationprocess.Theopticalcounterpartmustbepartofanextensivesystem,presumablylargelyobscured.LOCK850.53:Atypicalcounterpartconsistingoftwoopticalgalaxies,betrayedbytheir24-µmemission.

LOCK850.60:Severalplausibleidenti cationsat24µm,theclos-estofwhichjustfailstoqualifyasarobustcounterpart.LOCK850.63:AnotherplausibleAOtarget.

LOCK850.67:OpticallyfaintSMG,blankat1.4GHz,givenawaybyits24-µmemission.

LOCK850.70:Aclassicopticalpairbetrayedat24µmandbyweakradioemission.

LOCK850.77:AsLOCK850.34:apairofpairs.

LOCK850.79:AnotherSMGwithseveralplausibleidenti ca-tions,thoughonlyoneoftheseisstatisticallyrobust.

LOCK850.87:Opticallyinvisible,yetbrightat24µmand1.4GHz.

SXDF850.01:Opticallyinvisible,yetbrightat1.4GHz.

SXDF850.02:Theradiomorphologyresemblesthebaseofawide-angletailradiogalaxy.

SXDF850.03:Theradioemissionisapparentlyassociatedwithabright,nearbygalaxy,thoughthealignmentispoorandlensingofabackgroundSMGmustbeapossibility.

SXDF850.05:Seeminglyamulti-componentmerger;suf cientlybrightat24µmand1.4GHztosuggestitliesatrelativelylowred-shift.

SXDF850.06:Animmenselycomplexregionwithatleastthreeradio-detectedcomponents.Thebrightest24-µmidenti cationiscoincidentwiththeradiosourcemostdistantfromtheSMGcen-troid.

SXDF850.07:AnopticallyfaintSMGinacomplexregion,be-trayedbyits24-µmand1.4-GHzemission.

SXDF850.08:Arobustradioidenti cation,offsetbyseveralarcsecfromaplausible24-µmcounterpart.

SXDF850.10:Itisplausiblethatthesubmmemissionemanatesfrombetweenthehotspotsofalobe-dominatedradiogalaxy.

SXDF850.11:Anexcellent,clearlyidenti edtargetforAO-assistedstudy,exploitingthenearbystar.

SXDF850.12:AndistortedopticalcounterpartliesbeneathveryfaintradioemissionclosetotheSMGcentroid.

SXDF850.14:Near-coincident,faint24-µmand1.4-GHzemis-sion,thoughitwouldbetemptingtotargetthedistortedopticalgalaxynorthoftheSpitzeremissionforspectroscopy.