We present the catalogue of a wide-field CFHT/WHT spectroscopic survey of the lensing cluster Cl0024+1654 at z=0.395. This catalogue contains 618 new spectra, of which 581 have identified redshifts. Adding redshifts available from the literature, the final

9

Table 4. The catalogue. This table presents a selection from the sample, the full catalogue is available in electronic form at CDS. The rst seven entries correspond to the example spectra shown in Fig. 2. The next seven/six entries belong to the northern/southern groups at z～ 0.495, discussed in Sect. 4. Finally we list several objects in the vicinity of the dark structure detected by Bonnet, Mellier& Fort (1994). See the text for a description of the table contents.num O. Czoske et al.: Spectroscopic survey of Cl0024: I. The catalogue 531 221 80 625 103 540 378 209 315 519 537 546 562 567 51

3 528 556 579 580 610 518 542 544 552 563 566 576 ... R.A. 189.8 -117.1 -366.5 376.6 -323.9 206.2 3.9 -133.6 -34.2 175.1 199.7 216.7 240.2 251.0 169.4 184.6 230.6 268.7 271.4 332.6 175.0 209.8 211.3 226.9 240.6 246.2 262.0 ... Dec 414.9 150.3 -117.5 305.8 158.1 588.7 -5.6 596.3 559.5 558.2 599.4 589.7 531.6 545.7 393.7 374.3 271.1 353.6 363.7 387.9 255.1 261.6 243.4 245.0 256.7 279.9 260.8 ... z 0.3943 0.3938 0.3944 0.3900 0.3963 0.4907 0.3973 0.4892 0.4928 0.4912 0.4951 0.4877 0.4917 0.4980 0.5016 0.4969 0.4955 0.5000 0.4938 0.4939 0.0000 0.2981 0.1755 0.3935 0.3797 0.4000 0.3911 ... Q A A A B D A A A A A A C C A C A A B A B S A B A A A A ... V 21.70 20.46 23.46 21.41 21.88 21.03 22.58 22.48 22.28 21.32 21.37 21.81 20.23 20.30 22.98 22.24 23.47 23.57 21.94 22.45 21.78 22.34 19.98 23.02 20.56 21.49 21.86 ... V I 1.18 1.73 0.62 1.47 1.69 2.48— 1.20 1.68 2.35 2.39 2.33 1.24 1.58 1.87 2.12 2.35 2.04 2.28 2.16 3.07 0.97 1.39 1.09 1.61 1.63 1.77 ...[O ii] 23±3 77±15 12±2 78±5 33±2 8±1 10±2 10±2 21±4 1±2 3±2 14±4 6±2 20±3 31±11 53±8 8±1 ...[O iii] 6 109 48 6 9 19 ... Hα 12 ... Hβ 4 23 32 10 4 3 ... Hδ 4±1 3±1 4±2 5±1 5±2 3±1 5±1 ... 4000 A 1.1 1.8 1.1 1.4 1.7 1.7 1.1 1.4 1.5 1.8 1.4 1.2 1.1 1.2 1.4 1.7 1.5 1.5 1.4 0.0 1.1 1.1 1.4 1.4 1.6 ... S/N 11.7 16.9 2.3 11.0 3.6 10.4 5.9 11.7 23.2 8.1 5.5 6.3 6.4 8.7 6.2 9.5 5.0 5.9 9.3 5.1 9.4 4.7 4.8 21.7 10.2 12.4 ... Runs 2 3, D97 3 2 3 4 3 3 3 4 4 4 4 4 2 2 2 2 2, 2 2 2 2 2 2 2, 2 2 2 ... Lines H/K, Hζ, Hη, Hθ,[O ii]. . . br, H/K, Hζ, Hη, Hθ. . .[O ii], Hβ,[O iii] H/K, Hδ, Hγ, G, Hβ(ab) br G, Hβ(ab), br, Mg i[O ii],[O iii], Hβ, Hγ(em), Hδ(em). . . Hθ, Hη, Hζ, Hβ,[O ii]. . . H/K, Hζ, Hη, Hθ, Hβ. . . br, G, Hθ, Hη, NaD. . . H/K, Hη, Hθ, G H, Hγ, Hη Hγ, Hδ, G H/K, Hζ, Hη, Hθ, G. . . G, Hγ, Hδ, H/K, Hζ Hδ, G, Hγ, Hβ(ab), Hθ. . . H/K, Hδ, G, Hγ, Hθ. . . Hδ, H/K, Hθ, Hζ, G H/K, Hζ, Hη, G, Hβ(e+a). . . br,[O ii] NaD, Mg i, bands[O iii],[O ii] Mg i, Fe i, G, Hγ, br. . .[O ii], Hβ,[O iii], G, Hγ(em). . . H/K, Hζ, Hη, Hθ,[O ii]. . . H/K, Hδ, G, Hγ, Hβ(ab). . . br, H/K, Hθ, Hζ, Hη. . . ...

We present the catalogue of a wide-field CFHT/WHT spectroscopic survey of the lensing cluster Cl0024+1654 at z=0.395. This catalogue contains 618 new spectra, of which 581 have identified redshifts. Adding redshifts available from the literature, the final

10O.Czoskeetal.:SpectroscopicsurveyofCl0024:I.The

catalogue

Fig.4b.Continued.ThesquaresmarkthepositionsofFigs.9,thecircletheareaaroundtheweakshearsignaldetectedbyBonnet,Mellier&Fort(1994),discussedinSect.4.

Fig.4c.Continued

Column14:Signal-to-noiseratiomeasuredbetween4050and4250 A.

Column15:Number(s)oftheobservingrun(s)duringwhichtheobjectwasobserved(cf.Table1).Objectsob-servedbyDressleretal.(1999)aremarkedby“D”andthenumberfromtheircatalogue.

Column16:Linesthatcouldbeidenti edinthespec-trum/spectra.

Weprovidenewspectrafor618objects,ofwhich581haveredshifts.Theglobalsuccessrateistherefore94%.Notallredshiftsareequallysecurethough:Wequalify435ofourredshifts(70%)as“secure”(qualitycodeA),28(5%)as“uncertain”(codeD)and86(14%)ofinter-mediatequality.34objects(5%)turnedouttobestars.Thefractionof“secure”redshiftsis83%forforeground

galaxiesatz<0.37,82%forgalaxiesaroundthecluster

redshift(0.37<z<0.41),anddropsto53%forgalaxiesathigherredshift.

Forcompleteness,weincludeinthecataloguethered-shiftsprovidedbyDressleretal.(1999).Thecorrespond-ingentrynumberfromtheircatalogue(pre xedby‘D’)islistedincolumn15ofourcatalogue.ThecatalogueaspublishedbyDressleretal.(1999)contains130entries,ofwhich107areclustermembers.However,wenoticedseveralerrorsintheircatalogue,reducingthenumberofdistinctobjectsto1255.54oftheseobjectswereobservedbyusaswell,usuallywithconcordantredshifts,seethediscussioninSec.3.2andFig.3.Therewerehowever veproblematiccases:Dressleretal.givetheredshiftforob-ject376(D7)as0.3755,whereasourspectrumindicates