22 research outputs found
Galaxy and Mass Assembly (GAMA): Panchromatic data release (far-UV–far-IR) and the low-z energy budget
We present the Galaxy And Mass Assembly (GAMA) Panchromatic Data Release (PDR) constituting over 230 deg2 of imaging with photometry in 21 bands extending from the farUV to the far-IR. These data complement our spectroscopic campaign of over 300k galaxies, and are compiled from observations with a variety of facilities including: GALaxy Evolution eXplorer, Sloan Digital Sky Survey, Visible and Infrared Telescope for Astronomy (VISTA), Wide-field Infrared Survey Explorer, and Herschel, with the GAMA regions currently being surveyedbyVLTSurveyTelescope(VST)andscheduledforobservationsbyAustralianSquare Kilometer Array Pathfinder (ASKAP). These data are processed to a common astrometric solution, from which photometry is derived for ∼221373 galaxies with r < 19.8 mag. Online tools are provided to access and download data cutouts, or the full mosaics of the GAMA regions in each band. We focus, in particular, on the reduction and analysis of the VISTA VIsta Kilo-degree INfrared Galaxy data, and compare to earlier data sets (i.e. 2MASS and UKIDSS) before combining the data and examining its integrity. Having derived the 21-band photometric catalogue, we proceed to fit the data using the energy balance code MAGPHYS. These measurements are then used to obtain the first fully empirical measurement of the
0.1–500 μm energy output of the Universe. Exploring the cosmic spectral energy distribution
across three time-intervals (0.3–1.1, 1.1–1.8, and 1.8–2.4 Gyr), we find that the Universe is currently generating (1.5 ± 0.3) × 1035 h70 W Mpc−3, down from (2.5 ± 0.2) × 1035 h70 W Mpc−3 2.3 Gyr ago. More importantly, we identify significant and smooth evolution in the integrated photon escape fraction at all wavelengths, with the UV escape fraction increasing from 27(18) per cent at z= 0.18 in NUV(FUV) to 34(23) per cent at z= 0.06. The GAMA PDR can be found at: http://gama-psi.icrar.org/
Galaxy And Mass Assembly (GAMA):Panchromatic Data Release (far-UV–far-IR) and the low-z energy budget
CHILES VI:HI and H alpha observations for z <0.1 galaxies; probing HI spin alignment with filaments in the cosmic web
We present neutral hydrogen (HI) and ionized hydrogen (H)
observations of ten galaxies out to a redshift of 0.1. The HI observations are
from the first epoch (178 hours) of the COSMOS HI Large Extragalactic Survey
(CHILES). Our sample is HI biased and consists of ten late-type galaxies with
HI masses that range from M to
M. We find that although the majority of galaxies show irregularities
in the morphology and kinematics, they generally follow the scaling relations
found in larger samples. We find that the HI and H velocities reach
the flat part of the rotation curve. We identify the large-scale structure in
the nearby CHILES volume using DisPerSE with the spectroscopic catalog from
SDSS. We explore the gaseous properties of the galaxies as a function of
location in the cosmic web. We also compare the angular momentum vector (spin)
of the galaxies to the orientation of the nearest cosmic web filament. Our
results show that galaxy spins tend to be aligned with cosmic web filaments and
show a hint of a transition mass associated with the spin angle alignment.Comment: 24 pages, 25 figures, 6 tables, accepted for publication in MNRA
Galaxy And Mass Assembly: the evolution of the cosmic spectral energy distribution from z = 1 to z = 0
We present the evolution of the cosmic spectral energy distribution (CSED) from z = 1 to 0. Our CSEDs originate from stacking individual spectral energy distribution (SED) fits based on panchromatic photometry from the Galaxy And Mass Assembly (GAMA) and COSMOS data sets in 10 redshift intervals with completeness corrections applied. Below z = 0.45, we have credible SED fits from 100 nm to 1 mm. Due to the relatively low sensitivity of the far-infrared data, our far-infrared CSEDs contain a mix of predicted and measured fluxes above z = 0.45. Our results include appropriate errors to highlight the impact of these corrections. We show that the bolometric energy output of the Universe has declined by a factor of roughly 4 – from 5.1 ± 1.0 at z ∼ 1 to 1.3 ± 0.3 × 1035 h70 W Mpc−3 at the current epoch. We show that this decrease is robust to cosmic sample variance, the SED modelling and other various types of error. Our CSEDs are also consistent with an increase in the mean age of stellar populations. We also show that dust attenuation has decreased over the same period, with the photon escape fraction at 150 nm increasing from 16 ± 3 at z ∼ 1 to 24 ± 5 per cent at the current epoch, equivalent to a decrease in AFUV of 0.4 mag. Our CSEDs account for 68 ± 12 and 61 ± 13 per cent of the cosmic optical and infrared backgrounds, respectively, as defined from integrated galaxy counts and are consistent with previous estimates of the cosmic infrared background with redshift
GAMA/H-ATLAS: the local dust mass function and cosmic density as a function of galaxy type - a benchmark for models of galaxy evolution
We present the dust mass function (DMF) of 15,750 galaxies with redshift z < 0:1, drawn from the overlapping area of the GAMA and H-ATLAS surveys. The DMF is derived using the density corrected Vmax method, where we estimate Vmax using: (i) the normal photometric selection limit (pVmax) and (ii) a bivariate brightness distribution (BBD) technique, which accounts for two selection effects. We fit the data with a Schechter function, and find M* = (4:65 ± 0.18) × 10^7 h^2/70 Mo, α = (-1.22 ± 0:01), Φ*= (6.26 ± 0.28) × 10^-3 h^3/70 Mpc^-3 dex^-1. The resulting dust mass density parameter integrated down to 10^4 M☉ is Ωd = (1.11 ± 0.02) × 10^-6 which implies the mass fraction of baryons in dust is fmb = (2.40 ± 0.04) × 10^-5; cosmic variance adds an extra 7-17 per cent uncertainty to the quoted statistical errors. Our measurements have fewer galaxies with high dust mass than predicted by semi-analytic models. This is because the models include too much dust in high stellar mass galaxies. Conversely, our measurements find more galaxies with high dust mass than predicted by hydrodynamical cosmological simulations. This is likely to be from the long timescales for grain growth assumed in the models. We calculate DMFs split by galaxy type and find dust mass densities of Ωd = (0.88 ± 0.03) × 10^-6 and Ωd = (0.060 ± 0.005) × 10^-6 for late-types and early-types respectively. Comparing to the equivalent galaxy stellar mass functions (GSMF) we find that the DMF for late-types is well matched by the GMSF scaled by (8.07 ± 0.35) × 10^-4
CHILES. VII. Deep Imaging for the CHILES Project, an SKA Prototype
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.Radio astronomy is undergoing a renaissance, as the next generation of instruments provides a massive leap forward in collecting area and therefore raw sensitivity. However, to achieve this theoretical level of sensitivity in the science data products, we need to address the much more pernicious systematic effects, which are the true limitation. These become all the more significant when we consider that much of the time used by survey instruments, such as the Square Kilometre Array (SKA), will be dedicated to deep surveys. CHILES is a deep H i survey of the COSMOS field, with 1000 hr of Very Large Array time. We present our approach for creating the image cubes from the first epoch, with discussions of the methods and quantification of the data quality from 946 to 1420 MHz—a redshift range of 0.5−0. We lay out the problems we had to solve and describe how we tackled them. These are important because CHILES is the first deep wide-band multiepoch H i survey and has relevance for ongoing and future surveys. We focus on the accumulated systematic errors in the imaging, as the goal is to deliver a high-fidelity image that is only limited by the random thermal errors. To understand and correct these systematic effects, we ideally manage them in the domain in which they arise, and that is predominately the visibility domain. CHILES is a perfect test bed for many of the issues we can expect for deep imaging with the SKA or ngVLA, and we discuss the lessons we have learned. © 2022. The Author(s). Published by the American Astronomical Society.he CHILES survey was partially supported by a collaborative research grant from the National Science Foundation under grant Nos. AST—1412843, 1412578, 1413102, 1413099, and 1412503. This research was supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in three Dimensions (ASTRO-3D), through project No. CE170100013, and by grants from Amazon Web Services, the AstroCompute project. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement with Associated Universities Inc. Source flux densities in Table 2 were taken from the NASA/IPAC Extragalactic Database (NED), which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. J.M.v.d.H. acknowledges support from the European Research Council under the European Unions Seventh Framework Programme (FP/2007-2013)/ERC grant agreement No. 291531 (HIStoryNU). D.J.P., N.L., and E.S. acknowledge partial support from NSF grants No. AST 1412578 and AST-1149491 and from the WVU Eberly College Dean's office. K. R. acknowledges support from the Bundesministerium für Bildung und Forschung (BMBF) award 05A20WM4. K.M.H. acknowledges funding from the State Agency for Research of the Spanish Ministry of Science, Innovation and Universities through the "Center of Excellence Severo Ochoa" awarded to the Instituto de AstrofÃsica de AndalucÃa (SEV-2017-0709); from grant RTI2018-096228-B-C31 (Ministry of Science, Innovation and Universities/State Agency for Research/European Regional Development Funds, European Union); and from the coordination of the participation in SKA-SPAIN, funded by the Ministry of Science and innovation (MICIN).Peer reviewe
Galaxy And Mass Assembly (GAMA): Panchromatic Data Release (far-UV-far-IR) and the low-z energy budget
Galaxy And Mass Assembly (GAMA): Panchromatic Data Release (far-UV-far-IR) and the low-z energy budget
Galaxy And Mass Assembly (GAMA): Panchromatic Data Release (far-UV-far-IR) and the low-z energy budget
We present the Galaxy And Mass Assembly (GAMA) Panchromatic Data Release (PDR) constituting over 230 deg2 of imaging with photometry in 21 bands extending from the farUV to the far-IR. These data complement our spectroscopic campaign of over 300k galaxies, and are compiled from observations with a variety of facilities including: GALaxy Evolution eXplorer, Sloan Digital Sky Survey, Visible and Infrared Telescope for Astronomy (VISTA), Wide-field Infrared Survey Explorer, and Herschel, with the GAMA regions currently being surveyed by VLT Survey Telescope (VST) and scheduled for observations by Australian Square Kilometer Array Pathfinder (ASKAP). These data are processed to a common astrometric solution, from which photometry is derived for ∼221 373 galaxies with r < 19.8 mag. Online tools are provided to access and download data cutouts, or the full mosaics of the GAMA regions in each band. We focus, in particular, on the reduction and analysis of the VISTA VIsta Kilo-degree INfrared Galaxy data, and compare to earlier data sets (i.e. 2MASS and UKIDSS) before combining the data and examining its integrity. Having derived the 21-band photometric catalogue, we proceed to fit the data using the energy balance code MAGPHYS. These measurements are then used to obtain the first fully empirical measurement of the 0.1–500 μm energy output of the Universe. Exploring the cosmic spectral energy distribution across three time-intervals (0.3–1.1, 1.1–1.8, and 1.8–2.4 Gyr), we find that the Universe is currently generating (1.5 ± 0.3) × 1035 h70 W Mpc−3, down from (2.5 ± 0.2) × 1035 h70 W Mpc−3 2.3 Gyr ago. More importantly, we identify significant and smooth evolution in the integrated photon escape fraction at all wavelengths, with the UV escape fraction increasing from 27(18) per cent at z = 0.18 in NUV(FUV) to 34(23) per cent at z = 0.06. The GAMA PDR can be found at: http://gama-psi.icrar.org/
Galaxy And Mass Assembly (GAMA): Panchromatic Data Release (far-UV --- far-IR) and the low-z energy budget
We present the GAMA Panchromatic Data Release (PDR) constituting over 230deg of imaging with photometry in 21 bands extending from the far-UV to the far-IR. These data complement our spectroscopic campaign of over 300k galaxies, and are compiled from observations with a variety of facilities including: GALEX, SDSS, VISTA, WISE, and Herschel, with the GAMA regions currently being surveyed by VST and scheduled for observations by ASKAP. These data are processed to a common astrometric solution, from which photometry is derived for 221,373 galaxies with r<19.8 mag. Online tools are provided to access and download data cutouts, or the full mosaics of the GAMA regions in each band. We focus, in particular, on the reduction and analysis of the VISTA VIKING data, and compare to earlier datasets (i.e., 2MASS and UKIDSS) before combining the data and examining its integrity. Having derived the 21-band photometric catalogue we proceed to fit the data using the energy balance code MAGPHYS. These measurements are then used to obtain the first fully empirical measurement of the 0.1-500m energy output of the Universe. Exploring the Cosmic Spectral Energy Distribution (CSED) across three time-intervals (0.3-1.1Gyr, 1.1-1.8~Gyr and 1.8---2.4~Gyr), we find that the Universe is currently generating h W Mpc, down from h W Mpc 2.3~Gyr ago. More importantly, we identify significant and smooth evolution in the integrated photon escape fraction at all wavelengths, with the UV escape fraction increasing from 27(18)% at z=0.18 in NUV(FUV) to 34(23)% at z=0.06. The GAMA PDR will allow for detailed studies of the energy production and outputs of individual systems, sub-populations, and representative galaxy samples at . The GAMA PDR can be found at: http://gama-psi.icrar.org