Browsing by Author "Postman, M."

Now showing 1 - 12 of 12
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    CHARACTERIZING FAINT GALAXIES IN THE REIONIZATION EPOCH : LBT CONFIRMS TWO L < 0.2 L-star SOURCES AT z=6.4 BEHIND THE CLASH/FRONTIER FIELDS CLUSTER MACS0717.5+3745
    (2014) Vanzella, E.; Fontana, A.; Zitrin, A.; Coe, D.; Bradley, L.; Postman, M.; Grazian, A.; Castellano, M.; Pentericci, L.; Infante Lira, Leopoldo
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    CLASH : A CENSUS OF MAGNIFIED STAR-FORMING GALAXIES AT z similar to 6-8
    (2014) Bradley, L.; Zitrin, A.; Coe, D.; Bouwens, R.; Postman, M.; Balestra, I.; Grillo, C.; Monna, A.; Rosati, P.; Carrasco, M.
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    CLASH : Photometric redshifts with 16 HST bands in galaxy cluster fields
    (2014) Jouvel, S.; Host, O.; Lahav, O.; Seitz, S.; Molino, A.; Coe, D.; Postman, M.; Moustakas, L.; Benítez, N.; Infante Lira, Leopoldo
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    CLASH : the concentration-mass relation of galaxy clusters
    (2015) Merten, J.; Meneghetti, M.; Postman, M.; Umetsu, K.; Zitrin, A.; Medezinski, E.; Nonino, M.; Koekemoer, A.; Melchior, P.; Infante Lira, Leopoldo; Gruen, D.; Moustakas, L.; Bartelmann, M.; Host, O.; Donahue, M.; Coe, D.; Carrasco, M.
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    Clash : Z ~ 6 young galaxy candidate quintuply lensed by the frontier field cluster RXC J2248.7-4431
    (2014) Monna, A.; Seitz, S.; Greisel, N.; Eichner, T.; Drory, N.; Postman, M.; Zitrin, A.; Coe, D.; Halkola, A.; Infante Lira, Leopoldo
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    CLASH-X : A COMPARISON OF LENSING AND X-RAY TECHNIQUES FOR MEASURING THE MASS PROFILES OF GALAXY CLUSTERS
    (2014) Donahue, M.; Voit, G.; Mahdavi, A.; Umetsu, K.; Ettori, S.; Merten, J.; Postman, M.; Hoffer, A.; Baldi, A.; Infante Lira, Leopoldo
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    EVIDENCE FOR UBIQUITOUS HIGH-EQUIVALENT-WIDTH NEBULAR EMISSION IN z similar to 7 GALAXIES : TOWARD A CLEAN MEASUREMENT OF THE SPECIFIC STAR-FORMATION RATE USING A SAMPLE OF BRIGHT, MAGNIFIED GALAXIES
    (2014) Smit, R.; Bouwens, R. J.; Labbé, I.; Zheng, W.; Lemze, D.; Ford, H.; Bradley, L.; Coe, D.; Postman, M.; Infante Lira, Leopoldo
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    Scaling Relations and Overabundance of Massive Clusters at z >~ 1 from Weak-lensing Studies with the Hubble Space Telescope
    (2011) Jee, M. J.; Dawson, K. S.; Hoekstra, H.; Perlmutter, S.; Rosati, P.; Brodwin, M.; Suzuki, N.; Koester, B.; Postman, M.; Lubin, L.; Meyers, J.; Stanford, S. A.; Barbary, K.; Barrientos, F.; Eisenhardt, P.; Ford, H. C.; Gilbank, D. G.; Gladders, M. D.; Gonzalez, A.; Harris, D. W.; Huang, X.; Lidman, C.; Rykoff, E. S.; Rubin, D.; Spadafora, A. L.
    We present weak gravitational lensing analysis of 22 high-redshift (z greater than or similar to 1) clusters based on Hubble Space Telescope images. Most clusters in our sample provide significant lensing signals and are well detected in their reconstructed two-dimensional mass maps. Combining the current results and our previous weak-lensing studies of five other high-z clusters, we compare gravitational lensing masses of these clusters with other observables. We revisit the question whether the presence of the most massive clusters in our sample is in tension with the current. CDM structure formation paradigm. We find that the lensing masses are tightly correlated with the gas temperatures and establish, for the first time, the lensing mass-temperature relation at z greater than or similar to 1. For the power-law slope of the M-T-X relation (M proportional to T-alpha), we obtain alpha = 1.54 +/- 0.23. This is consistent with the theoretical self-similar prediction alpha = 3/2 and with the results previously reported in the literature for much lower redshift samples. However, our normalization is lower than the previous results by 20%-30%, indicating that the normalization in the M-T-X relation might evolve. After correcting for Eddington bias and updating the discovery area with a more conservative choice, we find that the existence of the most massive clusters in our sample still provides a tension with the current. CDM model. The combined probability of finding the four most massive clusters in this sample after the marginalization over cosmological parameters is less than 1%.
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    The cluster lensing and supernova survey with hubble: an overview
    (2011) Postman, M.; Infante Lira, Leopoldo
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    The contribution of halos with different mass ratios to the overall growth of cluster-sized halos
    (2013) Lemze, D.; Postman, M.; Genel, S.; Ford, H.; Balestra, I.; Donahue, M.; Kelson, D.; Nonino, M.; Mercurio, A.; Infante Lira, Leopoldo; Biviano, A.
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    The Hubble Space Telescope Cluster Supernova Survey. III. Correlated Properties of Type Ia Supernovae and Their Hosts at 0.9 < Z < 1.46
    (2012) Meyers, J.; Aldering, G.; Barbary, K.; Barrientos, L. F.; Brodwin, M.; Dawson, K. S.; Deustua, S.; Doi, M.; Eisenhardt, P.; Faccioli, L.; Fakhouri, H. K.; Fruchter, A. S.; Gilbank, D. G.; Gladders, M. D.; Goldhaber, G.; Gonzalez, A. H.; Hattori, T.; Hsiao, E.; Ihara, Y.; Kashikawa, N.; Koester, B.; Konishi, K.; Lidman, C.; Lubin, L.; Morokuma, T.; Oda, T.; Perlmutter, S.; Postman, M.; Ripoche, P.; Rosati, P.; Rubin, D.; Rykoff, E.; Spadafora, A.; Stanford, S. A.; Suzuki, N.; Takanashi, N.; Tokita, K.; Yasuda, N.; Supernova Cosmology Project, The
    Using the sample of Type Ia supernovae (SNe Ia) discovered by the Hubble Space Telescope (HST) Cluster Supernova Survey and augmented with HST-observed SNe Ia in the Great Observatories Origins Deep Survey (GOODS) fields, we search for correlations between the properties of SNe and their host galaxies at high redshift. We use galaxy color and quantitative morphology to determine the red sequence in 25 clusters and develop a model to distinguish passively evolving early-type galaxies from star-forming galaxies in both clusters and the field. With this approach, we identify 6 SN Ia hosts that are early-type cluster members and 11 SN Ia hosts that are early-type field galaxies. We confirm for the first time at z > 0.9 that SNe Ia hosted by early-type galaxies brighten and fade more quickly than SNe Ia hosted by late-type galaxies. We also show that the two samples of hosts produce SNe Ia with similar color distributions. The relatively simple spectral energy distributions expected for passive galaxies enable us to measure stellar masses of early-type SN hosts. In combination with stellar mass estimates of late-type GOODS SN hosts from Thomson & Chary, we investigate the correlation of host mass with Hubble residual observed at lower redshifts. Although the sample is small and the uncertainties are large, a hint of this relation is found atz > 0.9. By simultaneously fitting the average cluster galaxy formation history and dust content to the red-sequence scatters, we show that the reddening of early-type cluster SN hosts is likely E(B - V) less than or similar to 0.06. The similarity of the field and cluster early-type host samples suggests that field early-type galaxies that lie on the red sequence may also be minimally affected by dust. Hence, the early-type-hosted SNe Ia studied here occupy a more favorable environment to use as well-characterized high-redshift standard candles than other SNe Ia.
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    THE MUSIC OF CLASH : PREDICTIONS ON THE CONCENTRATION-MASS RELATION
    (2014) Meneghetti, M.; Rasia, E.; Vega, J.; Merten, J.; Postman, M.; Yepes, G.; Sembolini, F.; Donahue, M.; Ettori, S.; Infante Lira, Leopoldo