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Correcting for fibre assignment incompleteness in the DESI Bright Galaxy Survey

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Correcting for fibre assignment incompleteness in the DESI Bright Galaxy Survey. / Smith, Alex; He, Jian Hua; Cole, Shaun; Stothert, Lee; Norberg, Peder; Baugh, Carlton; Bianchi, Davide; Wilson, Michael J.; Brooks, David; Forero-Romero, Jaime E.; Moustakas, John; Percival, Will J.; Tarle, Gregory; Wechsler, Risa H.

In: Monthly Notices of the Royal Astronomical Society, Vol. 484, No. 1, 01.03.2019, p. 1285-1300.

Research output: Contribution to journalArticle

Harvard

Smith, A, He, JH, Cole, S, Stothert, L, Norberg, P, Baugh, C, Bianchi, D, Wilson, MJ, Brooks, D, Forero-Romero, JE, Moustakas, J, Percival, WJ, Tarle, G & Wechsler, RH 2019, 'Correcting for fibre assignment incompleteness in the DESI Bright Galaxy Survey', Monthly Notices of the Royal Astronomical Society, vol. 484, no. 1, pp. 1285-1300. https://doi.org/10.1093/mnras/stz059

APA

Smith, A., He, J. H., Cole, S., Stothert, L., Norberg, P., Baugh, C., ... Wechsler, R. H. (2019). Correcting for fibre assignment incompleteness in the DESI Bright Galaxy Survey. Monthly Notices of the Royal Astronomical Society, 484(1), 1285-1300. https://doi.org/10.1093/mnras/stz059

Vancouver

Smith A, He JH, Cole S, Stothert L, Norberg P, Baugh C et al. Correcting for fibre assignment incompleteness in the DESI Bright Galaxy Survey. Monthly Notices of the Royal Astronomical Society. 2019 Mar 1;484(1):1285-1300. https://doi.org/10.1093/mnras/stz059

Author

Smith, Alex ; He, Jian Hua ; Cole, Shaun ; Stothert, Lee ; Norberg, Peder ; Baugh, Carlton ; Bianchi, Davide ; Wilson, Michael J. ; Brooks, David ; Forero-Romero, Jaime E. ; Moustakas, John ; Percival, Will J. ; Tarle, Gregory ; Wechsler, Risa H. / Correcting for fibre assignment incompleteness in the DESI Bright Galaxy Survey. In: Monthly Notices of the Royal Astronomical Society. 2019 ; Vol. 484, No. 1. pp. 1285-1300.

Bibtex

@article{e0d62407a4ce44dc8edb612ffb66d42c,
title = "Correcting for fibre assignment incompleteness in the DESI Bright Galaxy Survey",
abstract = "The Dark Energy Spectroscopic Instrument (DESI) Bright Galaxy Survey (BGS) will be a survey of bright, low-redshift galaxies, which is planned to cover an area of ∼14 000 square degrees in three passes. Each pass will cover the survey area with ∼2000 pointings, each of area ∼8 square degrees. The BGS is currently proposed to consist of a bright high priority sample to an r-band magnitude limit r ∼ 19.5, with a fainter low priority sample to r ∼ 20. The geometry of the DESI fibre positioners in the focal plane of the telescope affects the completeness of the survey and has a non-trivial impact on clustering measurements. Using a BGS mock catalogue, we show that completeness due to fibre assignment primarily depends on the surface density of galaxies. Completeness is high (>95 per cent) in low-density regions, but very low (<10 per cent) in the centre of massive clusters. We apply the pair inverse probability (PIP) weighting correction to clustering measurements from a BGS mock which has been through the fibre assignment algorithm. This method is only unbiased if it is possible to observe every galaxy pair. To facilitate this, we randomly promote a small fraction of the fainter sample to be high priority, and dither the set of tile positions by a small angle. We show that inverse pair weighting combined with angular upweighting provides an unbiased correction to galaxy clustering measurements for the complete three pass survey, and also after one pass, which is highly incomplete.",
keywords = "(cosmology:) large-scale structure of Universe, Cosmology: observations, Galaxies: statistics, RCUK, STFC, ST/M503472/1, ST/L00075X/1, ST/K00042X/1, ST/H008519/1, ST/K00087X/1",
author = "Alex Smith and He, {Jian Hua} and Shaun Cole and Lee Stothert and Peder Norberg and Carlton Baugh and Davide Bianchi and Wilson, {Michael J.} and David Brooks and Forero-Romero, {Jaime E.} and John Moustakas and Percival, {Will J.} and Gregory Tarle and Wechsler, {Risa H.}",
year = "2019",
month = "3",
day = "1",
doi = "10.1093/mnras/stz059",
language = "English",
volume = "484",
pages = "1285--1300",
journal = "MNRAS",
issn = "0035-8711",
publisher = "Oxford University Press",
number = "1",

}

RIS

TY - JOUR

T1 - Correcting for fibre assignment incompleteness in the DESI Bright Galaxy Survey

AU - Smith, Alex

AU - He, Jian Hua

AU - Cole, Shaun

AU - Stothert, Lee

AU - Norberg, Peder

AU - Baugh, Carlton

AU - Bianchi, Davide

AU - Wilson, Michael J.

AU - Brooks, David

AU - Forero-Romero, Jaime E.

AU - Moustakas, John

AU - Percival, Will J.

AU - Tarle, Gregory

AU - Wechsler, Risa H.

PY - 2019/3/1

Y1 - 2019/3/1

N2 - The Dark Energy Spectroscopic Instrument (DESI) Bright Galaxy Survey (BGS) will be a survey of bright, low-redshift galaxies, which is planned to cover an area of ∼14 000 square degrees in three passes. Each pass will cover the survey area with ∼2000 pointings, each of area ∼8 square degrees. The BGS is currently proposed to consist of a bright high priority sample to an r-band magnitude limit r ∼ 19.5, with a fainter low priority sample to r ∼ 20. The geometry of the DESI fibre positioners in the focal plane of the telescope affects the completeness of the survey and has a non-trivial impact on clustering measurements. Using a BGS mock catalogue, we show that completeness due to fibre assignment primarily depends on the surface density of galaxies. Completeness is high (>95 per cent) in low-density regions, but very low (<10 per cent) in the centre of massive clusters. We apply the pair inverse probability (PIP) weighting correction to clustering measurements from a BGS mock which has been through the fibre assignment algorithm. This method is only unbiased if it is possible to observe every galaxy pair. To facilitate this, we randomly promote a small fraction of the fainter sample to be high priority, and dither the set of tile positions by a small angle. We show that inverse pair weighting combined with angular upweighting provides an unbiased correction to galaxy clustering measurements for the complete three pass survey, and also after one pass, which is highly incomplete.

AB - The Dark Energy Spectroscopic Instrument (DESI) Bright Galaxy Survey (BGS) will be a survey of bright, low-redshift galaxies, which is planned to cover an area of ∼14 000 square degrees in three passes. Each pass will cover the survey area with ∼2000 pointings, each of area ∼8 square degrees. The BGS is currently proposed to consist of a bright high priority sample to an r-band magnitude limit r ∼ 19.5, with a fainter low priority sample to r ∼ 20. The geometry of the DESI fibre positioners in the focal plane of the telescope affects the completeness of the survey and has a non-trivial impact on clustering measurements. Using a BGS mock catalogue, we show that completeness due to fibre assignment primarily depends on the surface density of galaxies. Completeness is high (>95 per cent) in low-density regions, but very low (<10 per cent) in the centre of massive clusters. We apply the pair inverse probability (PIP) weighting correction to clustering measurements from a BGS mock which has been through the fibre assignment algorithm. This method is only unbiased if it is possible to observe every galaxy pair. To facilitate this, we randomly promote a small fraction of the fainter sample to be high priority, and dither the set of tile positions by a small angle. We show that inverse pair weighting combined with angular upweighting provides an unbiased correction to galaxy clustering measurements for the complete three pass survey, and also after one pass, which is highly incomplete.

KW - (cosmology:) large-scale structure of Universe

KW - Cosmology: observations

KW - Galaxies: statistics

KW - RCUK

KW - STFC

KW - ST/M503472/1

KW - ST/L00075X/1

KW - ST/K00042X/1

KW - ST/H008519/1

KW - ST/K00087X/1

UR - http://www.scopus.com/inward/record.url?scp=85066997574&partnerID=8YFLogxK

U2 - 10.1093/mnras/stz059

DO - 10.1093/mnras/stz059

M3 - Article

AN - SCOPUS:85066997574

VL - 484

SP - 1285

EP - 1300

JO - MNRAS

JF - MNRAS

SN - 0035-8711

IS - 1

ER -

ID: 15848243