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

6O.Czoskeetal.:SpectroscopicsurveyofCl0024:I.Thecatalogue

Table1.Logofthespectroscopicobservingruns.

124–27/08/92CFHT/MOSSAIC1O300224–27/08/95CFHT/MOSLoral-3O300312–15/09/96WHT/LDSS-2LOR1med/blue411–13/11/96CFHT/MOSSTIS-2O300-1allqualities

“secure/A”onlyRunsN(z1 z2)N2–2198.2—198.23–364.8—45.84–4

9

6.6

—

7

5.4

forcedtorecoverourredshiftidenti cationandweonlyusedxcsao’serrorestimate.

Forlargevaluesofthecorrelationparameter,R>3(Kurtz&Mink1998),we ndthatxcsaoreproducesourinputredshiftsverywell.Themeandeviationbetweenby-eyeredshiftandxcsaoredshiftis

24.5–7.5180.3774.31Feige11066.6–15.6150.3143.69Wolf134695.4–7.2150.3573.30HZ4

36.6–8.1210.4405.03Hiltner600

(z1 z2)betweentheobservationsis

consistentwithzero.

FinallywecompareinFig.3theredshiftsforthose54objectsthatwereobservedbothbyusandbyDressleretal.(1999).Forthemajorityoftheseobjectsthered-shiftmeasurementsagreeverywell,however,thereare veclearmisidenti cations,withredshiftdeviationofmorethan0.01;thesecasesarediscussedindetailinSect.3.4.Object523deviatesbymorethan3σifthe vemisidenti- cationsaredroppedfromthesample,soweexcludethisobjectaswell.Theremaining48commonobjectshaveameanredshiftdeviation

of