Welcome to GLASS


Recent News

Linking Star Formation to Cluster Environments with GLASS

GLASS Paper VII: The Spatial Distribution of Star Formation Using GLASS data, Vulcani et al. (2016a) analyzed the spatial distribution of star ...

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GLASS Reveals Dual-Role Environments in Galaxy Clusters

Using the GLASS spectroscopic and very deep imaging data, Morishita et al. (2016) found that galaxy clusters are dual-role environments, which both ...

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MACS0416 lens model and surface mass density map from GLASS spectroscopy

In Hoag et al. (2016), the GLASS team used the GLASS spectroscopy combined with the deep imaging from the Hubble ...

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Completion of GLASS NIR data release v001

With the release of the NIR data products and redshift catalogs for the clusters A370, MACS0416, MACS0744, the GLASS NIR ...

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GLASS Fall 2015 release available

The GLASS data products, including the GLASS redshift catalogs, for the HFF clusters A2744 and MACS1149 are now available on ...

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GLASS is a cycle-21 large program with the Hubble Space Telescope, targeting 10 massive clusters, including the 6 Frontier Fields, using the WFC3 and ACS grisms. The program consists of 140 primary orbits (with the G102 and G141 grisms) and 140 parallel orbits (with the G800L grism). Using the clusters as cosmic telescopes, GLASS is taking spectra of faint background galaxies with unprecedented sensitivity and angular resolution. GLASS has three primary science drivers, although a variety of other science investigations are possible in combination with existing and planned imaging campaigns like the Frontier Fields Initiative and CLASH .

The key science drivers of GLASS are:

– To shed light upon the role of galaxies in reionizing the universe, the topology of high redshift intergalactic/interstellar medium and on Lyman alpha escape fraction.
– To study gas accretion, star formation and outflows by mapping spatially resolved star formation and metallicity gradients in galaxies at z = 1.3 – 2.3.
– To study the environmental dependence of galaxy evolution, by mapping spatially resolved star formation in galaxies in the cluster cores and infalling regions.

The survey strategy, science drivers, released data products and software tools are all described in the GLASS survey paper Treu et al. (2015)

If you find any of the GLASS products useful, please cite: