Recursos de colección

Caltech Authors (157.532 recursos)

Repository of works by Caltech published authors.

Group = SPLASH

Mostrando recursos 1 - 20 de 39

  1. The bright end of the galaxy luminosity function at z =7: before the onset of mass quenching?

    Bowler, R. A. A.; Dunlop, J. S.; McLure, R. J.; Rogers, A. B.; McCracken, H. J.; Milvang-Jensen, B.; Furusawa, H.; Fynbo, J. P. U.; Taniguchi, Y.; Afonso, J.; Bremer, M. N.; Le Fèvre, O.
    We present the results of a new search for bright star-forming galaxies at redshift z ≃ 7 within the UltraVISTA second data release (DR2) and UKIDSS (UKIRT Infrared Deep Sky Survey) UDS (Ultra Deep Survey) DR10 data, which together provide 1.65 deg^2 of near-infrared imaging with overlapping optical and Spitzer data. Using a full photometric redshift analysis, to identify high-redshift galaxies and reject contaminants, we have selected a sample of 34 luminous (−22.7

  2. The bright end of the galaxy luminosity function at z =7: before the onset of mass quenching?

    Bowler, R. A. A.; Dunlop, J. S.; McLure, R. J.; Rogers, A. B.; McCracken, H. J.; Milvang-Jensen, B.; Furusawa, H.; Fynbo, J. P. U.; Taniguchi, Y.; Afonso, J.; Bremer, M. N.; Le Fèvre, O.
    We present the results of a new search for bright star-forming galaxies at redshift z ≃ 7 within the UltraVISTA second data release (DR2) and UKIDSS (UKIRT Infrared Deep Sky Survey) UDS (Ultra Deep Survey) DR10 data, which together provide 1.65 deg^2 of near-infrared imaging with overlapping optical and Spitzer data. Using a full photometric redshift analysis, to identify high-redshift galaxies and reject contaminants, we have selected a sample of 34 luminous (−22.7

  3. Wide-Field InfrarRed Survey Telescope-Astrophysics Focused Telescope Assets WFIRST-AFTA 2015 Report

    Spergel, D.; Gehrels, N.; Baltay, C.; Bennett, D.; Breckinridge, J.; Donahue, M.; Dressler, A.; Gaudi, B. S.; Greene, T.; Guyon, O.; Hirata, C.; Kalirai, J.; Kasdin, N. J.; Macintosh, B.; Moos, W.; Perlmutter, S.; Postman, M.; Rauscher, B.; Rhodes, J.; Wang, Y.; Weinberg, D.; Benford, D.; Hudson, M.; Jeong, W. -S.; Mellier, Y.; Traub, W.; Yamada, T.; Capak, P.; Colbert, J.; Masters, D.; Penny, M.; Savransky, D.; Stern, D.; Zimmerman, N.; Barry, R.; Bartusek, L.; Carpenter, K.; Cheng, E.; Content, D.; Dekens, F.; Demers, R.; Grady, K.; Jackson, C.; Kuan, G.; Kruk, J.; Melton, M.; Nemati, B.; Parvin, B.; Poberezhskiy, I.; Peddie, C.; Ruffa, J.; Wallace, J. K.; Whipple, A.; Wollack, E.; Zhao, F.
    This report describes the 2014 study by the Science Definition Team (SDT) of the Wide-Field Infrared Survey Telescope (WFIRST) mission. It is a space observatory that will address the most compelling scientific problems in dark energy, exoplanets and general astrophysics using a 2.4-m telescope with a wide-field infrared instrument and an optical coronagraph. The Astro2010 Decadal Survey recommended a Wide Field Infrared Survey Telescope as its top priority for a new large space mission. As conceived by the decadal survey, WFIRST would carry out a dark energy science program, a microlensing program to determine the demographics of exoplanets, and a general observing...

  4. Wide-Field InfrarRed Survey Telescope-Astrophysics Focused Telescope Assets WFIRST-AFTA 2015 Report

    Spergel, D.; Gehrels, N.; Baltay, C.; Bennett, D.; Breckinridge, J.; Donahue, M.; Dressler, A.; Gaudi, B. S.; Greene, T.; Guyon, O.; Hirata, C.; Kalirai, J.; Kasdin, N. J.; Macintosh, B.; Moos, W.; Perlmutter, S.; Postman, M.; Rauscher, B.; Rhodes, J.; Wang, Y.; Weinberg, D.; Benford, D.; Hudson, M.; Jeong, W. -S.; Mellier, Y.; Traub, W.; Yamada, T.; Capak, P.; Colbert, J.; Masters, D.; Penny, M.; Savransky, D.; Stern, D.; Zimmerman, N.; Barry, R.; Bartusek, L.; Carpenter, K.; Cheng, E.; Content, D.; Dekens, F.; Demers, R.; Grady, K.; Jackson, C.; Kuan, G.; Kruk, J.; Melton, M.; Nemati, B.; Parvin, B.; Poberezhskiy, I.; Peddie, C.; Ruffa, J.; Wallace, J. K.; Whipple, A.; Wollack, E.; Zhao, F.
    This report describes the 2014 study by the Science Definition Team (SDT) of the Wide-Field Infrared Survey Telescope (WFIRST) mission. It is a space observatory that will address the most compelling scientific problems in dark energy, exoplanets and general astrophysics using a 2.4-m telescope with a wide-field infrared instrument and an optical coronagraph. The Astro2010 Decadal Survey recommended a Wide Field Infrared Survey Telescope as its top priority for a new large space mission. As conceived by the decadal survey, WFIRST would carry out a dark energy science program, a microlensing program to determine the demographics of exoplanets, and a general observing...

  5. The galaxy-halo connection from a joint lensing, clustering and abundance analysis in the CFHTLenS/VIPERS field

    Coupon, J.; Arnouts, S.; van Waerbeke, L.; Moutard, T.; Ilbert, O.; van Uitert, E.; Erben, T.; Garilli, B.; Guzzo, L.; Heymans, C.; Hildebrandt, H.; Hoekstra, H.; Kilbinger, M.; Kitching, T.; Mellier, Y.; Miller, L.; Scodeggio, M.; Bonnett, C.; Branchini, E.; Davidzon, I.; De Lucia, G.; Fritz, A.; Fu, L.; Hudelot, P.; Hudson, M. J.; Kuijken, K.; Leauthaud, A.; Le Fèvre, O.; McCracken, H. J.; Moscardini, L.; Rowe, B. T. P.; Schrabback, T.; Semboloni, E.; Velander, M.
    We present new constraints on the relationship between galaxies and their host dark matter haloes, measured from the location of the peak of the stellar-to-halo mass ratio (SHMR), up to the most massive galaxy clusters at redshift z ∼ 0.8 and over a volume of nearly 0.1 Gpc3. We use a unique combination of deep observations in the CFHTLenS/VIPERS field from the near-UV to the near-IR, supplemented by ∼60 000 secure spectroscopic redshifts, analysing galaxy clustering, galaxy–galaxy lensing and the stellar mass function. We interpret our measurements within the halo occupation distribution (HOD) framework, separating the contributions from central and satellite...

  6. The CHANDRA COSMOS Legacy Survey: Optical / IR Identifications

    Marchesi, S.; Civano, F.; Elvis, M.; Salvato, M.; Brusa, M.; Comastri, A.; Gilli, R.; Hasinger, G.; Lanzuisi, G.; Miyaji, T.; Treister, E.; Urry, C. M.; Vignali, C.; Zamorani, G.; Allevato, V.; Cappelluti, N.; Cardamone, C.; Finoguenov, A.; Griffiths, R. E.; Karim, A.; Laigle, C.; LaMassa, S. M.; Jahnke, K.; Ranalli, P.; Schawinski, K.; Schinnerer, E.; Silverman, J. D.; Smolcic, V.; Suh, H.; Trakhtenbrot, B.
    We present the catalog of optical and infrared counterparts of the Chandra COSMOS-Legacy Survey, a 4.6 Ms Chandra program on the 2.2 deg2 of the COSMOS field, combination of 56 new overlapping observations obtained in Cycle 14 with the previous C-COSMOS survey. In this Paper we report the i, K, and 3.6 μm identifications of the 2273 X-ray point sources detected in the new Cycle 14 observations. We use the likelihood ratio technique to derive the association of optical/infrared (IR) counterparts for 97% of the X-ray sources. We also update the information for the 1743 sources detected in C-COSMOS, using...

  7. The galaxy UV luminosity function at z≃ 2–4; new results on faint-end slope and the evolution of luminosity density

    Parsa, Shaghayegh; Dunlop, James S.; McLure, Ross J.; Mortlock, Alice
    We present a new, robust measurement of the evolving rest-frame ultraviolet (UV) galaxy luminosity function (LF) over the key redshift range from z ≃ 2 to z ≃ 4. Our results are based on the high dynamic range provided by combining the Hubble Ultra Deep Field (HUDF), CANDELS/GOODS-South, and UltraVISTA/COSMOS surveys. We utilize the unparalleled multifrequency photometry available in this survey ‘wedding cake’ to compile complete galaxy samples at z ≃ 2, 3, 4 via photometric redshifts (calibrated against the latest spectroscopy) rather than colour–colour selection, and to determine accurate rest-frame UV absolute magnitudes (M1500) from spectral energy distribution (SED)...

  8. z≳ 7 galaxies with red Spitzer/IRAC [3.6]-[4.5] colors in the full CANDELS data set: The brightest-known galaxies at z~ 7-9 and a probable spectroscopic confirmation at z = 7.48

    Roberts-Borsani, G. W.; Bouwens, R. J.; Oesch, P. A.; Labbe, I.; Smit, R.; Illingworth, G. D.; van Dokkum, P. G.; Holden, B.; Gonzalez, V.; Stefanon, M.; Holwerda, B.; Wilkins, S.
    We identify four unusually bright (H ${}_{160,{AB}}$ < 25.5) galaxies from Hubble Space Telescope (HST) and Spitzer CANDELS data with probable redshifts z ~ 7–9. These identifications include the brightest-known galaxies to date at z gsim 7.5. As Y-band observations are not available over the full CANDELS program to perform a standard Lyman-break selection of z > 7 galaxies, we employ an alternate strategy using deep Spitzer/IRAC data. We identify z ~ 7.1–9.1 galaxies by selecting z gsim 6 galaxies from the HST CANDELS data that show quite red IRAC [3.6]−[4.5] colors, indicating strong [O iii]+Hβ lines in the 4.5...

  9. The rest-frame optical (900nm) galaxy luminosity function at z~4-7: abundance matching points to limited evolution in the Mstar/Mhalo ratio at z>4

    Stefanon, Mauro; Bouwens, Rychard J.; Labbé, Ivo; Muzzin, Adam; Marchesini, Danilo; Oesch, Pascal; Gonzalez, Valentino
    We present the first determination of the galaxy luminosity function (LF) at z~4, 5, 6 and 7 in the rest-frame optical at lambda_rest~900 nm (z' band). The rest-frame optical light traces the content in low-mass evolved stars (~stellar mass - Mstar), minimizing potential measurement biases for Mstar. Moreover it is less affected by nebular line emission contamination and dust attenuation, is independent of stellar population models, and can be probed up to z~8 through Spitzer/IRAC. Our analysis leverages the unique full depth Spitzer/IRAC 3.6um-to-8.0um data over the CANDELS/GOODS-N, CANDELS/GOODS-S and COSMOS/UltraVISTA fields. We find that at absolute magnitudes M_z' fainter than >-23 mag, M_z' linearly correlates with M_UV,1600. At...

  10. Gas Fraction and depletion time of massive star-forming galaxies at z ∼ 3.2: No change in global star formation process out to z > 3

    Schinnerer, E.; Groves, B.; Sargent, M. T.; Karim, A.; Oesch, P. A.; Magnelli, B.; LeFevre, O.; Tasca, L.; Civano, F.; Cassata, P.; Smolčić, V.
    The observed evolution of the gas fraction and its associated depletion time in main-sequence (MS) galaxies provides insights on how star formation proceeds over cosmic time. We report ALMA detections of the rest-frame ~300 μm continuum observed at 240 GHz for 45 massive ($\langle \mathrm{log}({M}_{\star }({M}_{\odot }))\rangle =10.7$), normal star-forming ($\langle \mathrm{log}(\mathrm{sSFR}({\mathrm{yr}}^{-1}))\rangle =-8.6$), i.e., MS, galaxies at $z\approx 3.2$ in the COSMOS field. From an empirical calibration between cold neutral, i.e., molecular and atomic, gas mass ${M}_{\mathrm{gas}}$ and monochromatic (rest-frame) infrared luminosity, the gas mass for this sample is derived. Combined with stellar mass ${M}_{\star }$ and star formation rate...

  11. The COSMOS2015 galaxy stellar mass function: 13 billion years of stellar mass assembly in 10 snapshots

    Davidzon, I.; Ilbert, O.; Laigle, C.; Coupon, J.; McCracken, H. J.; Delvecchio, I.; Masters, D.; Capak, P. L.; Hsieh, B. C.; Tresse, L.; Le Fevre, O.; Bethermin, M.; Chang, Y. -Y.; Faisst, A. L.; Le Floc'h, E.; Steinhardt, C.; Toft, S.; Aussel, H.; Dubois, C.; Hasinger, G.; Salvato, M.; Sanders, D. B.; Scoville, N.; Silverman, J. D.
    We measure the stellar mass function (SMF) of galaxies in the COSMOS field up to $z\sim6$. We select them in the near-IR bands of the COSMOS2015 catalogue, which includes ultra-deep photometry from UltraVISTA-DR2, SPLASH, and Subaru/Hyper-SuprimeCam. At $z>2.5$ we use new precise photometric redshifts with error $\sigma_z=0.03(1+z)$ and an outlier fraction of $12\%$, estimated by means of the unique spectroscopic sample of COSMOS. The increased exposure time in the DR2, along with our panchromatic detection strategy, allow us to improve the stellar mass completeness at high $z$ with respect to previous UltraVISTA catalogues. We also identify passive galaxies through a robust colour-colour selection, extending their SMF estimate up to...

  12. The COSMOS2015 galaxy stellar mass function: Thirteen billion years of stellar mass assembly in ten snapshots

    Davidzon, I.; Ilbert, O.; Laigle, C.; Coupon, J.; McCracken, H. J.; Delvecchio, I.; Masters, D.; Capak, P.; Hsieh, B. C.; Le Fèvre, O.; Tresse, L.; Bethermin, M.; Chang, Y.-Y.; Faisst, A. L.; Le Floc'h, E.; Steinhardt, C.; Toft, S.; Aussel, H.; Dubois, C.; Hasinger, G.; Salvato, M.; Sanders, D. B.; Scoville, N.; Silverman, J. D.
    We measure the stellar mass function (SMF) and stellar mass density of galaxies in the COSMOS field up to z ~ 6. We select them in the near-IR bands of the COSMOS2015 catalogue, which includes ultra-deep photometry from UltraVISTA-DR2, SPLASH, and Subaru/Hyper Suprime-Cam. At z > 2.5 we use new precise photometric redshifts with error σ_z = 0.03(1 + z) and an outlier fraction of 12%, estimated by means of the unique spectroscopic sample of COSMOS (~100 000 spectroscopic measurements in total, more than one thousand having robust z_(spec)> 2.5). The increased exposure time in the DR2, along with our...

  13. The COSMOS2015 galaxy stellar mass function: Thirteen billion years of stellar mass assembly in ten snapshots

    Davidzon, I.; Ilbert, O.; Laigle, C.; Coupon, J.; McCracken, H. J.; Delvecchio, I.; Masters, D.; Capak, P.; Hsieh, B. C.; Le Fèvre, O.; Tresse, L.; Bethermin, M.; Chang, Y.-Y.; Faisst, A. L.; Le Floc'h, E.; Steinhardt, C.; Toft, S.; Aussel, H.; Dubois, C.; Hasinger, G.; Salvato, M.; Sanders, D. B.; Scoville, N.; Silverman, J. D.
    We measure the stellar mass function (SMF) and stellar mass density of galaxies in the COSMOS field up to z ~ 6. We select them in the near-IR bands of the COSMOS2015 catalogue, which includes ultra-deep photometry from UltraVISTA-DR2, SPLASH, and Subaru/Hyper Suprime-Cam. At z > 2.5 we use new precise photometric redshifts with error σ_z = 0.03(1 + z) and an outlier fraction of 12%, estimated by means of the unique spectroscopic sample of COSMOS (~100 000 spectroscopic measurements in total, more than one thousand having robust z_(spec)> 2.5). The increased exposure time in the DR2, along with our...

  14. G10/COSMOS: 38 band (far-UV to far-IR) panchromatic photometry using LAMBDAR

    Andrews, S. K.; Driver, S. P.; Davies, L. J. M.; Kafle, Prajwal R.; Robotham, Aaron S. G.; Wright, Angus H.
    We present a consistent total flux catalogue for a ∼1 deg2 subset of the Cosmic Evolution Survey (COSMOS) region (RA ∈ [149 ∘. .∘ 55, 150 ∘. .∘ 65], Dec. ∈ [1 ∘. .∘ 80, 2 ∘. .∘ 73]) with near-complete coverage in 38 bands from the far-ultraviolet to the far-infrared. We produce aperture matched photometry for 128 304 objects with i < 24.5 in a manner that is equivalent to the Wright et al. catalogue from the low-redshift (z < 0.4) Galaxy and Mass Assembly (GAMA) survey. This catalogue is based on publicly available imaging from GALEX, Canada–France–Hawaii Telescope, Subaru, Visible and Infrared Survey Telescope for Astronomy, Spitzer and...

  15. The environment and host haloes of the brightest z~6 Lyman-break galaxies

    Hatfield, P. W.; Bowler, R. A. A.; Jarvis, M. J.; Hale, C. L.
    By studying the large-scale structure of the bright high-redshift Lyman-break galaxy (LBG) population it is possible to gain an insight into the role of environment in galaxy formation physics in the early Universe. We measure the clustering of a sample of bright ($-22.7

  16. Characterizing the evolving K-band luminosity function using the UltraVISTA, CANDELS and HUDF surveys

    Mortlock, Alice; McLure, Ross J.; Bowler, Rebecca A. A.; McLeod, Derek J.; Mármol-Queraltó, Esther; Parsa, Shaghayegh; Dunlop, James S.; Bruce, Victoria A.
    We present the results of a new study of the K-band galaxy luminosity function (KLF) at redshifts z ≤ 3.75, based on a nested combination of the UltraVISTA, Cosmic Assembly Near-infrared Deep Legacy Extragalactic Survey and HUDF surveys. The large dynamic range in luminosity spanned by this new data set (3–4 dex over the full redshift range) is sufficient to clearly demonstrate for the first time that the faint-end slope of the KLF at z ≥ 0.25 is relatively steep (−1.3 ≤ α ≤ −1.5 for a single Schechter function), in good agreement with recent theoretical and phenomenological models. Moreover,...

  17. Unveiling the nature of bright z ≃ 7 galaxies with the Hubble Space Telescope

    Bowler, R. A. A.; Dunlop, J. S.; McLure, R. J.; McLeod, D. J.
    We present new Hubble Space Telescope/Wide Field Camera 3 (HST/WFC3) imaging of 25 extremely luminous (−23.2 ≤ MUV ≲ −21.2) Lyman-break galaxies (LBGs) at z ≃ 7. The sample was initially selected from 1.65 deg2 of ground-based imaging in the UltraVISTA/COSMOS and UDS/SXDS fields, and includes the extreme Lyman α emitters, ‘Himiko’ and ‘CR7’. A deconfusion analysis of the deep Spitzer photometry available suggests that these galaxies exhibit strong rest-frame optical nebular emission lines (EW0(Hβ + [O III]) > 600 Å). We find that irregular, multiple-component morphologies suggestive of clumpy or merging systems are common (fmulti > 0.4) in bright z ≃...

  18. No evidence for Population III stars or a direct collapse black hole in the z = 6.6 Lyman α emitter ‘CR7’

    Bowler, R. A. A.; McLure, R. J.; Dunlop, J. S.; McLeod, D. J.; Stanway, E. R.; Eldridge, J. J.; Jarvis, M. J.
    The z = 6.6 Lyman α emitter ‘CR7’ has been claimed to have a Population III (Pop III) like stellar population, or alternatively, be a candidate direct collapse black hole (DCBH). In this paper, we investigate the evidence for these exotic scenarios using recently available, deeper, optical, near-infrared and mid-infrared imaging. We find strong Spitzer/Infrared Array Camera detections for the main component of CR7 at 3.6 and 4.5 μm, and show that it has a blue colour ([3.6] − [4.5] = −1.2 ± 0.3). This colour cannot be reproduced by current Pop III or pristine DCBH models. Instead, the results suggest that...

  19. HST imaging of the brightest z~8-9 galaxies from UltraVISTA: the extreme bright end of the UV luminosity function

    Stefanon, Mauro; Labbé, Ivo; Bouwens, Rychard J.; Brammer, Gabriel B.; Oesch, Pascal; Franx, Marijn; Fynbo, Johan P. U.; Milvang-Jensen, Bo; Muzzin, Adam; Illingworth, Garth D.; Le Fèvre, Olivier; Caputi, Karina I.; Holwerda, Benne W.; McCracken, Henry J.; Smit, Renske; Magee, Dan
    We report on the discovery of three especially bright candidate zphot & 8 galaxies. Five sources were targeted for follow-up with HST/WFC3, selected from a larger sample of 16 bright (24.8 . H . 25.5 mag) candidate z & 8 LBGs identified over the 1.6 degrees2 of the COSMOS/UltraVISTA field. These were identified as Y and J dropouts by leveraging the deep (Y -to-KS ∼ 25.6 − 25.2 mag, 5σ) NIR data from the UltraVISTA DR3 release, deep ground based optical imaging from the CFHTLS and Subaru Suprime Cam programs and Spitzer/IRAC mosaics combining observations from the SMUVS and SPLASH programs. Through the refined spectral...

  20. HST imaging of the brightest z~8-9 galaxies from UltraVISTA: the extreme bright end of the UV luminosity function

    Stefanon, Mauro; Labbé, Ivo; Bouwens, Rychard J.; Brammer, Gabriel B.; Oesch, Pascal; Franx, Marijn; Fynbo, Johan P. U.; Milvang-Jensen, Bo; Muzzin, Adam; Illingworth, Garth D.; Le Fèvre, Olivier; Caputi, Karina I.; Holwerda, Benne W.; McCracken, Henry J.; Smit, Renske; Magee, Dan
    We report on the discovery of three especially bright candidate zphot & 8 galaxies. Five sources were targeted for follow-up with HST/WFC3, selected from a larger sample of 16 bright (24.8 . H . 25.5 mag) candidate z & 8 LBGs identified over the 1.6 degrees2 of the COSMOS/UltraVISTA field. These were identified as Y and J dropouts by leveraging the deep (Y -to-KS ∼ 25.6 − 25.2 mag, 5σ) NIR data from the UltraVISTA DR3 release, deep ground based optical imaging from the CFHTLS and Subaru Suprime Cam programs and Spitzer/IRAC mosaics combining observations from the SMUVS and SPLASH programs. Through the refined spectral...

Aviso de cookies: Usamos cookies propias y de terceros para mejorar nuestros servicios, para análisis estadístico y para mostrarle publicidad. Si continua navegando consideramos que acepta su uso en los términos establecidos en la Política de cookies.