CF-HiZELS, an similar to 10 deg(2) emission-line survey with spectroscopic follow-up: H alpha, [O III] plus H beta and [O II] luminosity functions at z=0.8, 1.4 and 2.2

TY - JOUR

T1 - CF-HiZELS, an similar to 10 deg(2) emission-line survey with spectroscopic follow-up

T2 - H alpha, [O III] plus H beta and [O II] luminosity functions at z=0.8, 1.4 and 2.2

AU - Sobral, David

AU - Matthee, J.

AU - Best, P.N.

AU - Smail, Ian

AU - Khostovan, A.A.

AU - Milvang-Jensen, Bo

AU - Kim, J.-W

AU - Stott, J.

AU - Calhau, J.

AU - Nayyeri, H.

AU - Mobasher, B.

PY - 2015/8/11

Y1 - 2015/8/11

N2 - We present results from the largest contiguous narrow-band survey in the near-infrared. We have used the wide-field infrared camera/Canada-France-Hawaii Telescope and the lowOH2 filter (1.187 ± 0.005 μm) to survey ≈ 10 deg2 of contiguous extragalactic sky in the SA22 field. A total of ~6000 candidate emission-line galaxies are found. We use deep ugrizJK data to obtain robust photometric redshifts. We combine our data with the High-redshift(Z) Emission Line Survey (HiZELS), explore spectroscopic surveys (VVDS, VIPERS) and obtain our own spectroscopic follow-up with KMOS, FMOS and MOSFIRE to derive large samples of high-redshift emission-line selected galaxies: 3471 Hα emitters at z = 0.8, 1343 [O III] + Hβ emitters at z = 1.4 and 572 [O II] emitters at z = 2.2. We probe comoving volumes of >106 Mpc3 and find significant overdensities, including an 8.5σ (spectroscopically confirmed) overdensity of Hα emitters at z = 0.81. We derive Hα, [O III] + Hβ and [O II] luminosity functions at 0.8, 1.4, 2.2, respectively, and present implications for future surveys such as Euclid. Our uniquely large volumes/areas allow us to subdivide the samples in thousands of randomized combinations of areas and provide a robust empirical measurement of sample/cosmic variance. We show that surveys for star-forming/emission-line galaxies at a depth similar to ours can only overcome cosmic-variance (errors <10 per cent) if they are based on volumes >5 × 105 Mpc3; errors on L* and ϕ{symbol}* due to sample (cosmic) variance on surveys probing ~104 and ~105 Mpc3 are typically very high: ~300 and ~40-60 per cent, respectively.

AB - We present results from the largest contiguous narrow-band survey in the near-infrared. We have used the wide-field infrared camera/Canada-France-Hawaii Telescope and the lowOH2 filter (1.187 ± 0.005 μm) to survey ≈ 10 deg2 of contiguous extragalactic sky in the SA22 field. A total of ~6000 candidate emission-line galaxies are found. We use deep ugrizJK data to obtain robust photometric redshifts. We combine our data with the High-redshift(Z) Emission Line Survey (HiZELS), explore spectroscopic surveys (VVDS, VIPERS) and obtain our own spectroscopic follow-up with KMOS, FMOS and MOSFIRE to derive large samples of high-redshift emission-line selected galaxies: 3471 Hα emitters at z = 0.8, 1343 [O III] + Hβ emitters at z = 1.4 and 572 [O II] emitters at z = 2.2. We probe comoving volumes of >106 Mpc3 and find significant overdensities, including an 8.5σ (spectroscopically confirmed) overdensity of Hα emitters at z = 0.81. We derive Hα, [O III] + Hβ and [O II] luminosity functions at 0.8, 1.4, 2.2, respectively, and present implications for future surveys such as Euclid. Our uniquely large volumes/areas allow us to subdivide the samples in thousands of randomized combinations of areas and provide a robust empirical measurement of sample/cosmic variance. We show that surveys for star-forming/emission-line galaxies at a depth similar to ours can only overcome cosmic-variance (errors <10 per cent) if they are based on volumes >5 × 105 Mpc3; errors on L* and ϕ{symbol}* due to sample (cosmic) variance on surveys probing ~104 and ~105 Mpc3 are typically very high: ~300 and ~40-60 per cent, respectively.

U2 - 10.1093/mnras/stv1076

DO - 10.1093/mnras/stv1076

M3 - Journal article

SN - 0035-8711

VL - 451

SP - 2303

EP - 2323

JO - Royal Astronomical Society. Monthly Notices

JF - Royal Astronomical Society. Monthly Notices

IS - 3

ER -