The calibration and data products of GALEX

Patrick Morrissey, Tim Conrow, Tom A. Barlow, Todd Small, Mark Seibert, Ted K. Wyder, Tamás Budavári, Stephane Arnouts, Peter G. Friedman, Karl Forster, D. Christopher Martin, Susan G. Neff, David Schiminovich, Luciana Bianchi, José Donas, Timothy M. Heckman, Young-Wook Lee, Barry F. Madore, Bruno Milliard, R. Michael Rich & 3 others Alex S. Szalay, Barry Y. Welsh, Sukyoung Yi

Research output: Contribution to journalArticle

581 Citations (Scopus)

Abstract

We describe the calibration status and data products pertaining to the GR2 and GR3 data releases of the Galaxy Evolution Explorer (GALEX). These releases have identical pipeline calibrations that are significantly improved over the GRl data release. GALEX continues to survey the sky in the far-ultraviolet (FUV, ∼ 154 nm) and near-ultraviolet (NUV, ∼232 nm) bands, providing simultaneous imaging with a pair of photon-counting, microchannel plate, delay line readout detectors. These 1.25° field of view detectors are well suited to ultraviolet observations because of their excellent red rejection and negligible background. A dithered mode of observing and photon list output pose complex requirements on the data processing pipeline, entangling detector calibrations, and aspect reconstruction algorithms. Recent improvements have achieved photometric repeatability of 0.05 and 0.03 mAB in the FUV and NUV, respectively. We have detected a long-term drift of order 1% FUV and 6% NUV over the mission. Astrometric precision is of order 0.5″ rms in both bands. In this paper we provide the GALEX user with a broad overview of the calibration issues likely to be confronted in the current release. Improvements are likely as the GALEX mission continues into an extended phase with a healthy instrument, no consumables, and increased opportunities for guest investigations.

Original languageEnglish
Pages (from-to)682-697
Number of pages16
JournalAstrophysical Journal, Supplement Series
Volume173
Issue number2
DOIs
Publication statusPublished - 2007 Dec 1

Fingerprint

data products
galaxies
calibration
products
detectors
microchannel plates
photons
delay lines
field of view
rejection
lists
readout
sky
counting
requirements
product
output
detector

All Science Journal Classification (ASJC) codes

  • Space and Planetary Science

Cite this

Morrissey, P., Conrow, T., Barlow, T. A., Small, T., Seibert, M., Wyder, T. K., ... Yi, S. (2007). The calibration and data products of GALEX. Astrophysical Journal, Supplement Series, 173(2), 682-697. https://doi.org/10.1086/520512
Morrissey, Patrick ; Conrow, Tim ; Barlow, Tom A. ; Small, Todd ; Seibert, Mark ; Wyder, Ted K. ; Budavári, Tamás ; Arnouts, Stephane ; Friedman, Peter G. ; Forster, Karl ; Martin, D. Christopher ; Neff, Susan G. ; Schiminovich, David ; Bianchi, Luciana ; Donas, José ; Heckman, Timothy M. ; Lee, Young-Wook ; Madore, Barry F. ; Milliard, Bruno ; Rich, R. Michael ; Szalay, Alex S. ; Welsh, Barry Y. ; Yi, Sukyoung. / The calibration and data products of GALEX. In: Astrophysical Journal, Supplement Series. 2007 ; Vol. 173, No. 2. pp. 682-697.
@article{ea0765abaac540dabe4e637e2158959b,
title = "The calibration and data products of GALEX",
abstract = "We describe the calibration status and data products pertaining to the GR2 and GR3 data releases of the Galaxy Evolution Explorer (GALEX). These releases have identical pipeline calibrations that are significantly improved over the GRl data release. GALEX continues to survey the sky in the far-ultraviolet (FUV, ∼ 154 nm) and near-ultraviolet (NUV, ∼232 nm) bands, providing simultaneous imaging with a pair of photon-counting, microchannel plate, delay line readout detectors. These 1.25° field of view detectors are well suited to ultraviolet observations because of their excellent red rejection and negligible background. A dithered mode of observing and photon list output pose complex requirements on the data processing pipeline, entangling detector calibrations, and aspect reconstruction algorithms. Recent improvements have achieved photometric repeatability of 0.05 and 0.03 mAB in the FUV and NUV, respectively. We have detected a long-term drift of order 1{\%} FUV and 6{\%} NUV over the mission. Astrometric precision is of order 0.5″ rms in both bands. In this paper we provide the GALEX user with a broad overview of the calibration issues likely to be confronted in the current release. Improvements are likely as the GALEX mission continues into an extended phase with a healthy instrument, no consumables, and increased opportunities for guest investigations.",
author = "Patrick Morrissey and Tim Conrow and Barlow, {Tom A.} and Todd Small and Mark Seibert and Wyder, {Ted K.} and Tam{\'a}s Budav{\'a}ri and Stephane Arnouts and Friedman, {Peter G.} and Karl Forster and Martin, {D. Christopher} and Neff, {Susan G.} and David Schiminovich and Luciana Bianchi and Jos{\'e} Donas and Heckman, {Timothy M.} and Young-Wook Lee and Madore, {Barry F.} and Bruno Milliard and Rich, {R. Michael} and Szalay, {Alex S.} and Welsh, {Barry Y.} and Sukyoung Yi",
year = "2007",
month = "12",
day = "1",
doi = "10.1086/520512",
language = "English",
volume = "173",
pages = "682--697",
journal = "Astrophysical Journal, Supplement Series",
issn = "0067-0049",
publisher = "IOP Publishing Ltd.",
number = "2",

}

Morrissey, P, Conrow, T, Barlow, TA, Small, T, Seibert, M, Wyder, TK, Budavári, T, Arnouts, S, Friedman, PG, Forster, K, Martin, DC, Neff, SG, Schiminovich, D, Bianchi, L, Donas, J, Heckman, TM, Lee, Y-W, Madore, BF, Milliard, B, Rich, RM, Szalay, AS, Welsh, BY & Yi, S 2007, 'The calibration and data products of GALEX', Astrophysical Journal, Supplement Series, vol. 173, no. 2, pp. 682-697. https://doi.org/10.1086/520512

The calibration and data products of GALEX. / Morrissey, Patrick; Conrow, Tim; Barlow, Tom A.; Small, Todd; Seibert, Mark; Wyder, Ted K.; Budavári, Tamás; Arnouts, Stephane; Friedman, Peter G.; Forster, Karl; Martin, D. Christopher; Neff, Susan G.; Schiminovich, David; Bianchi, Luciana; Donas, José; Heckman, Timothy M.; Lee, Young-Wook; Madore, Barry F.; Milliard, Bruno; Rich, R. Michael; Szalay, Alex S.; Welsh, Barry Y.; Yi, Sukyoung.

In: Astrophysical Journal, Supplement Series, Vol. 173, No. 2, 01.12.2007, p. 682-697.

Research output: Contribution to journalArticle

TY - JOUR

T1 - The calibration and data products of GALEX

AU - Morrissey, Patrick

AU - Conrow, Tim

AU - Barlow, Tom A.

AU - Small, Todd

AU - Seibert, Mark

AU - Wyder, Ted K.

AU - Budavári, Tamás

AU - Arnouts, Stephane

AU - Friedman, Peter G.

AU - Forster, Karl

AU - Martin, D. Christopher

AU - Neff, Susan G.

AU - Schiminovich, David

AU - Bianchi, Luciana

AU - Donas, José

AU - Heckman, Timothy M.

AU - Lee, Young-Wook

AU - Madore, Barry F.

AU - Milliard, Bruno

AU - Rich, R. Michael

AU - Szalay, Alex S.

AU - Welsh, Barry Y.

AU - Yi, Sukyoung

PY - 2007/12/1

Y1 - 2007/12/1

N2 - We describe the calibration status and data products pertaining to the GR2 and GR3 data releases of the Galaxy Evolution Explorer (GALEX). These releases have identical pipeline calibrations that are significantly improved over the GRl data release. GALEX continues to survey the sky in the far-ultraviolet (FUV, ∼ 154 nm) and near-ultraviolet (NUV, ∼232 nm) bands, providing simultaneous imaging with a pair of photon-counting, microchannel plate, delay line readout detectors. These 1.25° field of view detectors are well suited to ultraviolet observations because of their excellent red rejection and negligible background. A dithered mode of observing and photon list output pose complex requirements on the data processing pipeline, entangling detector calibrations, and aspect reconstruction algorithms. Recent improvements have achieved photometric repeatability of 0.05 and 0.03 mAB in the FUV and NUV, respectively. We have detected a long-term drift of order 1% FUV and 6% NUV over the mission. Astrometric precision is of order 0.5″ rms in both bands. In this paper we provide the GALEX user with a broad overview of the calibration issues likely to be confronted in the current release. Improvements are likely as the GALEX mission continues into an extended phase with a healthy instrument, no consumables, and increased opportunities for guest investigations.

AB - We describe the calibration status and data products pertaining to the GR2 and GR3 data releases of the Galaxy Evolution Explorer (GALEX). These releases have identical pipeline calibrations that are significantly improved over the GRl data release. GALEX continues to survey the sky in the far-ultraviolet (FUV, ∼ 154 nm) and near-ultraviolet (NUV, ∼232 nm) bands, providing simultaneous imaging with a pair of photon-counting, microchannel plate, delay line readout detectors. These 1.25° field of view detectors are well suited to ultraviolet observations because of their excellent red rejection and negligible background. A dithered mode of observing and photon list output pose complex requirements on the data processing pipeline, entangling detector calibrations, and aspect reconstruction algorithms. Recent improvements have achieved photometric repeatability of 0.05 and 0.03 mAB in the FUV and NUV, respectively. We have detected a long-term drift of order 1% FUV and 6% NUV over the mission. Astrometric precision is of order 0.5″ rms in both bands. In this paper we provide the GALEX user with a broad overview of the calibration issues likely to be confronted in the current release. Improvements are likely as the GALEX mission continues into an extended phase with a healthy instrument, no consumables, and increased opportunities for guest investigations.

UR - http://www.scopus.com/inward/record.url?scp=39449108942&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=39449108942&partnerID=8YFLogxK

U2 - 10.1086/520512

DO - 10.1086/520512

M3 - Article

VL - 173

SP - 682

EP - 697

JO - Astrophysical Journal, Supplement Series

JF - Astrophysical Journal, Supplement Series

SN - 0067-0049

IS - 2

ER -

Morrissey P, Conrow T, Barlow TA, Small T, Seibert M, Wyder TK et al. The calibration and data products of GALEX. Astrophysical Journal, Supplement Series. 2007 Dec 1;173(2):682-697. https://doi.org/10.1086/520512