Observations of the high redshift Universe through narrow-band filters have proven very successful in the last decade. The 4-m VISTA telescope, equipped with the wide-field camera VIRCAM, offers a... Show moreObservations of the high redshift Universe through narrow-band filters have proven very successful in the last decade. The 4-m VISTA telescope, equipped with the wide-field camera VIRCAM, offers a major step forward in wide-field near-infrared imaging, and in order to utilise VISTA's large field-of-view and sensitivity, the Dark Cosmology Centre provided a set of 16 narrow-band filters for VIRCAM. These NB118 filters are centered at a wavelength near 1.19 {$μ$}m in a region with few airglow emission lines. The filters allow the detection of H{$α$} emitters at z = 0.8, H{$β$} and [O iii] emitters at z {ap} 1.4, [O ii] emitters at z = 2.2, and Ly{$α$} emitters at z = 8.8. Based on guaranteed time observations of the COSMOS field we here present a detailed description and characterization of the filters and their performance. In particular we provide sky-brightness levels and depths for each of the 16 detector/filter sets and find that some of the filters show signs of some red-leak. We identify a sample of 2 { imes} 10$^{3}$ candidate emission-line objects in the data. Cross-correlating this sample with a large set of galaxies with known spectroscopic redshifts we determine the ''in situ'' passbands of the filters and find that they are shifted by about 3.5 - 4 nm (corresponding to 30% of the filter width) to the red compared to the expectation based on the laboratory measurements. Finally, we present an algorithm to mask out persistence in VIRCAM data. Scientific results extracted from the data will be presented separately. Based on observations collected at the European Southern Observatory, Chile, as part of programme 284.A-5026 (VISTA NB118 GTO, PI Fynbo) and 179.A-2005 (UltraVISTA, PIs Dunlop, Franx, Fynbo, {amp} Le F{è}vre). Show less
Muzzin, A.V.; Marchesini, D.; Stefanon, M.; Franx, M.; McCracken, H.; Milvang-Jensen, B.; ... ; Dokkum, P. van 2013
We present measurements of the stellar mass functions (SMFs) of star-forming and quiescent galaxies to z = 4 using a sample of 95,675 K$_s$ -selected galaxies in the COSMOS/UltraVISTA field. The... Show moreWe present measurements of the stellar mass functions (SMFs) of star-forming and quiescent galaxies to z = 4 using a sample of 95,675 K$_s$ -selected galaxies in the COSMOS/UltraVISTA field. The SMFs of the combined population are in good agreement with previous measurements and show that the stellar mass density of the universe was only 50%, 10%, and 1% of its current value at z ~{} 0.75, 2.0, and 3.5, respectively. The quiescent population drives most of the overall growth, with the stellar mass density of these galaxies increasing as {$ρ$}$_{star}$vprop(1 + z)$^{–4.7 ± 0.4}$ since z = 3.5, whereas the mass density of star-forming galaxies increases as {$ρ$}$_{star}$vprop(1 + z)$^{–2.3 ± 0.2}$. At z {gt} 2.5, star-forming galaxies dominate the total SMF at all stellar masses, although a non-zero population of quiescent galaxies persists to z = 4. Comparisons of the K$_s$ -selected star-forming galaxy SMFs with UV-selected SMFs at 2.5 {lt} z {lt} 4 show reasonable agreement and suggest that UV-selected samples are representative of the majority of the stellar mass density at z {gt} 3.5. We estimate the average mass growth of individual galaxies by selecting galaxies at fixed cumulative number density. The average galaxy with log(M $_{star}$/M $_{☉}$) = 11.5 at z = 0.3 has grown in mass by only 0.2 dex (0.3 dex) since z = 2.0 (3.5), whereas those with log(M $_{star}$/M $_{☉}$) = 10.5 have grown by {gt}1.0 dex since z = 2. At z {lt} 2, the time derivatives of the mass growth are always larger for lower-mass galaxies, which demonstrates that the mass growth in galaxies since that redshift is mass-dependent and primarily bottom-up. Lastly, we examine potential sources of systematic uncertainties in the SMFs and find that those from photo-z templates, stellar population synthesis modeling, and the definition of quiescent galaxies dominate the total error budget in the SMFs. Based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under ESO programme ID 179.A-2005 and on data products produced by TERAPIX and the Cambridge Astronomy Survey Unit on behalf of the UltraVISTA consortium. Show less
Ashby, M.; Willner, S.; Fazio, G.; Huang, J.; Arendt, R.; Barmby, P.; ... ; Yan, H. 2013
The Spitzer Extended Deep Survey (SEDS) is a very deep infrared survey within five well-known extragalactic science fields: the UKIDSS Ultra-Deep Survey, the Extended Chandra Deep Field South,... Show moreThe Spitzer Extended Deep Survey (SEDS) is a very deep infrared survey within five well-known extragalactic science fields: the UKIDSS Ultra-Deep Survey, the Extended Chandra Deep Field South, COSMOS, the Hubble Deep Field North, and the Extended Groth Strip. SEDS covers a total area of 1.46 deg$^{2}$ to a depth of 26 AB mag (3{$σ$}) in both of the warm Infrared Array Camera (IRAC) bands at 3.6 and 4.5 {$μ$}m. Because of its uniform depth of coverage in so many widely-separated fields, SEDS is subject to roughly 25% smaller errors due to cosmic variance than a single-field survey of the same size. SEDS was designed to detect and characterize galaxies from intermediate to high redshifts (z = 2-7) with a built-in means of assessing the impact of cosmic variance on the individual fields. Because the full SEDS depth was accumulated in at least three separate visits to each field, typically with six-month intervals between visits, SEDS also furnishes an opportunity to assess the infrared variability of faint objects. This paper describes the SEDS survey design, processing, and publicly-available data products. Deep IRAC counts for the more than 300,000 galaxies detected by SEDS are consistent with models based on known galaxy populations. Discrete IRAC sources contribute 5.6 {plusmn} 1.0 and 4.4 {plusmn} 0.8 nW m$^{-2}$ sr$^{-1}$ at 3.6 and 4.5 {$μ$}m to the diffuse cosmic infrared background (CIB). IRAC sources cannot contribute more than half of the total CIB flux estimated from DIRBE data. Barring an unexpected error in the DIRBE flux estimates, half the CIB flux must therefore come from a diffuse component. Show less
Michałowski, M.; Kamble, A.; Hjorth, J.; Malesani, D.; Reinfrank, R.; Bonavera, L.; ... ; Wiersema, K. 2012
