Integral-field spectroscopy at the resolution limit of large telescopes: the science program of OSIRIS at Keck

Integral- eldsp ectroscopyattheresolutionlimitoflargetelescop es:thescienceprogramofOSIRISatKeckA.Quirrenbacha,J.E.LarkinbKrabb ecM.BarczysD. LaFreniereaUniversityof California, San Diego, CenterforAstrophysicsandSpaceSciencesMail Co de0424,LaJolla, CA92093-0424, USAbUniversityof California, LosAngeles,Division of Astronom8371 MathSciences,LosAngeles,CA90095-1562, USAcUniversityof California, Berkeley,366 Le ConteHallBerkeley,CA94720-7300, USAABSTRACTOSIRIS (OH-Suppressing InfraRed Integral- eld Sp ectrograph) is a new facility instrument for the KeckOb-servatory.Starting in 2004, it will provide the capability of p erforming three-dimensional sp ectroscopyin thenear-infraredz,JHandKbandsattheresolution limitofKeckIItelescop e,whichisequipp edwithadaptiveopticsandalaserguidestar.TheinnovativcapabilitiesofOSIRISwillenablemanynewobserv-ingpro jects.GalaxiesintheearlyUniversewillbeamongmostterestingtargetsforOSIRIS,whichwillperformdetailedstudiesoftheirstellarcontentanddynamicalprop erties.Inmoreexoticob jects,suchasquasars,radiogalaxies,andmorenearbyactivegalacticnuclei,OSIRIScanelucidatetherelationofcentral black hole to the prop erties of the host galaxy, and the mechanism bywhich gas is fed into the centralengine.InthecenterofourownGalaxy,itwillbep ossibletosearchforsignaturesinteractionbetweenthe massive black hole and stars in its immediate vicinity.Closer to home, OSIRIS will p erform sp ectroscopicobservations ofyoungstarsandtheirenvironment,ofbrowndwarfs.Imagingsp ectroscopyofthegiantplanets, their mo ons, and asteroids will shed new light on meteorology, mineralogy,and volcanism in the SolarSystem.OSIRIS observations of Kuip er Belt ob jects will provide sucient sensitivity to establish their surfacecomp osition, which will contribute substantially to our understanding of the history of the Solar System.Keywords:sp ectrographs, adaptiveoptics, integral- eld sp ectroscopy, near-infrared, OH suppression, galaxies,active galactic nuclei, stellar clusters, star formation, planets1. THEOSIRISINSTRUMENTOSIRIS (OH-Suppressing InfraRed Integral- eld Sp ectrograph) is a new facility instrumentfor theKeck Obser-vatory; it will b e installed at the Keck I I telescop e in 2004.OSIRIS will takeadvantage of the existing adaptiveoptics system (Wizinowich et al. 2000, 2002) and the Keck laser guide star facility(Pennington et al. 2002) top erform near-infrared integral- eld sp ectroscopy at the di raction-limit of a 10 m telescop e.OSIRISisanintegral- eldsp ectrographwithaTIGER-typ edesign(Baconetal.1995).Itprovidessp ectral resolutionR= 3900, which is sucienttotakeadvantage of thedark sky b etween theOH emissionlines (Maihara et al. 1993).In its standard \wide-band" mo de, OSIRIS will take a 1700-pixel sp ectrum providingfull coverage of one of the infrared bands (z,JH,orK) for each one of 1024 spatial pixels arranged in a 1664rectangular grid.A second \narrow-band" mo de is available, in which shorter (400-pixel) sp ectra coering onlya partial band are taken for 6464 spatial pixels.Four pixel scales (0:0002, 0035, 005, and 01) provide a eld-of-view ranging from 0:0032128 to 164 for the wide-band mo de, and from 12828 to 64Further author information:(Send corresp ondence to A.Q.)A.Q.:E-mail:aquirrenbach@ucsd.eduJ.L.:E-mail:larkin@astro.ucla.eduA.K.:E-mail:krabb e@ssl.b erkeley.edu