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تسجيل مستخدم جديدThe Grism Lens-Amplified Survey from Space (GLASS). XIII. G800L optical spectra from the parallel fields
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L.E. Abramson
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We present a catalogue of 22755 objects with slitless, optical, Hubble Space Telescope (HST) spectroscopy from the Grism Lens-Amplified Survey from Space (GLASS). The data cover $sim$220 sq. arcmin to 7-orbit ($sim$10 ks) depth in 20 parallel pointings of the Advanced Camera for Surveys G800L grism. The fields are located 6 away from 10 massive galaxy clusters in the HFF and CLASH footprints. Thirteen of the fields have ancillary HST imaging from these or other programs to facilitate a large number of applications, from studying metal distributions at $zsim0.5$, to quasars at $zsim4$, to the star formation histories of hundreds of galaxies in between. The spectroscopic catalogue has a median redshift of $langle zrangle=0.6$ with a median uncertainty of $Delta z / (1+z)lesssim2%$ at $rm F814Wlesssim23$ AB. Robust continuum detections reach a magnitude fainter. The 5 $sigma$ limiting line flux is $f_{rm lim}approx5times10^{-17}rm~erg~s^{-1}~cm^{-2}$ and half of all sources have 50% of pixels contaminated at $lesssim$1%. All sources have 1- and 2-D spectra, line fluxes/uncertainties and identifications, redshift probability distributions, spectral models, and derived narrow-band emission line maps from the Grism Redshift and Line Analysis tool (GRIZLI). We provide other basic sample characterisations, show data examples, and describe sources and potential investigations of interest. All data and products will be available online along with software to facilitate their use.
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[abbreviated] We present a census of Lyalpha emission at $zgtrsim7$ utilizing deep near infrared HST grism spectroscopy from the first six completed clusters of the Grism Lens-Amplified Survey from Space (GLASS). In 24/159 photometrically selected ga
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fall. In a companion paper we contrast the properties of field and cluster galaxies, whereas here we correlate the properties of H{alpha} emitters to a number of tracers of the cluster environment to investigate its role in driving galaxy transformations. H{alpha} emitters are found in the clusters out to 0.5 virial radii, the maximum radius covered by GLASS. The peak of the H{alpha} emission is offset with respect to the peak of the UV-continuum. We decompose this offsets into a radial and tangential component. The radial compo- nent points away from the cluster center in 60% of the cases, with 95% confidence. The decompositions agree with cosmological simulations, i.e. the H{alpha} emission offset correlates with galaxy velocity and ram-pressure stripping signatures. Trends between H{alpha} emitter properties and surface mass density distributions and X-ray emissions emerge only for unrelaxed clusters. The lack of strong correlations with the global environment does not allow us to identify a unique environmental effect originating from the cluster center. In contrast, correla- tions between H{alpha} morphology and local number density emerge. We conclude that local effects, uncorrelated to the cluster-centric radius, play a more important role in shaping galaxy properties.
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