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We investigate the environmental dependence of the mass-metallicty (MZ) relation and it's connection to galaxy stellar structures and morphologies. In our studies, we analyze galaxies in massive clusters at z~0.4 from the CLASH (HST) and CLASH-VLT surveys and measure their gas metallicities, star-formation rates, stellar structures and morphologies. We establish the MZ relation for 90 cluster and 40 field galaxies finding a shift of ~-0.3 dex in comparison to the local trends seen in SDSS for the majority of galaxies with logM10^10Msun) lie below the main sequence which corresponds to the higher mass objects that reach solar abundances in the MZ diagram., Proceedings of IAU Symposium 309, Vienna, ed. B.L. Ziegler, F. Combes, H. Dannerbauer, M. Verdugo

XMMU J1229+0151 is a rich galaxy cluster with redshift z=0.975, that was serendipitously detected in X-rays within the scope of the XMM-Newton Distant Cluster Project. HST/ACS observations in the i775 and z850 passbands, as well as VLT/FORS2 spectroscopy were further obtained, in addition to follow-up Near-Infrared (NIR) imaging in J- and Ks-bands with NTT/SOFI. We investigate the photometric, structural and spectral properties of the early-type galaxies in the high-redshift cluster XMMU J1229+0151. Source detection and aperture photometry are performed in the optical and NIR imaging. Galaxy morphology is inspected visually and by means of Sersic profile fitting to the 21 spectroscopically confirmed cluster members in the ACS field of view. The i775-z850 colour-magnitude relation (CMR) is derived with a method based on galaxy magnitudes obtained by fitting the surface brightness of the galaxies with Sersic models. The i775-z850 CMR of the spectroscopic members shows a very tight red-sequence with a zero point of 0.86+-0.04 mag and intrinsic scatter equal to 0.039 mag. The CMR obtained with the galaxy models has similar parameters. Stellar masses and formation ages of the cluster galaxies are derived by fitting the observed spectral energy distributions (SED) with models based on Bruzual & Charlot 2003. We obtain a star formation weighted age of 4.3 Gyr for a median mass of 7.4e10 Msun. Instead of an unambiguous brightest cluster galaxy (BCG), we find three bright galaxies with a similar z850 magnitude, which are, in addition, the most massive cluster members, with ~ 2e11 Msun. Our results strengthen the current evidence for a lack of significant evolution of the scatter and slope of the red-sequence out to z~1., 12 pages, accepted for publication in A&A

We analyse the Kormendy relations (KRs) of the two Frontier Fields clusters, Abell S1063, at z = 0.348, and MACS J1149.5+2223, at z = 0.542, exploiting very deep Hubble Space Telescope photometry and VLT/MUSE integral field spectroscopy. With this novel dataset, we are able to investigate how the KR parameters depend on the cluster galaxy sample selection and how this affects studies of galaxy evolution based on the KR. We define and compare four different galaxy samples according to: (a) S\'ersic indices: early-type ('ETG'), (b) visual inspection: 'ellipticals', (c) colours: 'red', (d) spectral properties: 'passive'. The classification is performed for a complete sample of galaxies with m$_{\textit{F814W}} \le$ 22.5 ABmag (M$_{*}$ $\gtrsim 10^{10.0}$ M$_{\odot}$). To derive robust galaxy structural parameters, we use two methods: (1) an iterative estimate of structural parameters using images of increasing size, in order to deal with closely separated galaxies and (2) different background estimations, to deal with the Intracluster light contamination. The comparison between the KRs obtained from the different samples suggests that the sample selection could affect the estimate of the best-fitting KR parameters. The KR built with ETGs is fully consistent with the one obtained for ellipticals and passive. On the other hand, the KR slope built on the red sample is only marginally consistent with those obtained with the other samples. We also release the photometric catalogue with structural parameters for the galaxies included in the present analysis., Comment: 23 pages, 18 figures, Accepted for publication in MNRAS

We present high-resolution ($\sim 1"$), 1.5 GHz continuum observations of the brightest cluster galaxies (BCGs) of 13 CLASH (Cluster Lensing And Supernova survey with Hubble) clusters at $0.18, Comment: 19 pages, 11 figures, significantly improved following referee's comments. Accepted by ApJ

Since galaxy clusters sit at the high-end of the mass function, the number of galaxy clusters both massive and concentrated enough to yield particularly large Einstein radii poses useful constraints on cosmological and structure formation models. To date, less than a handful of clusters are known to have Einstein radii exceeding $\sim40$" (for a source at $z_{s}\simeq2$, nominally). Here, we report an addition to that list of the Sunyaev-Zel'dovich (SZ) selected cluster, PLCK G287.0+32.9 ($z=0.38$), the second-highest SZ-mass ($M_{500}$) cluster from the Planck catalog. We present the first strong lensing analysis of the cluster, identifying 20 sets of multiply-imaged galaxies and candidates in new \emph{Hubble Space Telescope} data, including a long, $l\sim22$" giant arc, as well as a quadruply-imaged, apparently bright (magnified to J$_{F110W}=$25.3 AB), likely high-redshift dropout galaxy at $z_{phot}=6.90$ [6.13--8.43] (95\% C.I.). Our analysis reveals a very large critical area (1.55 arcmin$^{2}$, $z_{s}\simeq2$), corresponding to an effective Einstein radius of $\theta_{E}\sim42$". The model suggests the critical area will expand to 2.58 arcmin$^{2}$ ($\theta_{E}\sim54$") for sources at $z_{s}\sim10$. Our work adds to recent efforts to model very massive clusters towards the launch of the James Webb Space Telescope, in order to identify the most useful cosmic lenses for studying the early Universe. Spectroscopic redshifts for the multiply-imaged galaxies and additional HST data will be necessary for refining the lens model and verifying the nature of the $z\sim7$ dropout., Comment: Published in ApJL; 8 pages, 5 figures, 1 table; V2: accepted version