J/MNRAS/498/609 AKARI North Ecliptic Pole field in CFHT u-band (Huang+, 2020)
CFHT MegaPrime/MegaCam u-band source catalogue of the AKARI North Ecliptic Pole
Wide field.
Huang T.-C., Matsuhara H., Goto T., Shim H., Kim S.J., Malkan M.A.,
Hashimoto T., Hwang H.S., Oi N., Toba Y., Lee D., Santos D.J.D., Takagi T.
<Mon. Not. R. Astron. Soc., 498, 609-620 (2020)>
=2020MNRAS.498..609H 2020MNRAS.498..609H (SIMBAD/NED BibCode)
ADC_Keywords: Infrared sources ; Positional data ; Optical ; Surveys
Keywords: methods: data analysis - catalogues - surveys - galaxies: evolution -
galaxies: photometry - ultraviolet: galaxies
Abstract:
The AKARI infrared (IR) space telescope conducted two surveys (Deep
and Wide) in the North Ecliptic Pole (NEP) field to find more than
100000 IR sources using its infrared camera (IRC). IRC's nine filters,
which cover wavebands from 2 to 24µm continuously, make AKARI
unique in comparison with other IR observatories such as Spitzer or
WISE. However, studies of the AKARI NEP-Wide field sources had been
limited due to the lack of follow-up observations in the ultraviolet
(UV) and optical. In this work, we present the Canada-France-Hawaii
Telescope MegaPrime/MegaCam u-band source catalogue of the AKARI
NEP-Wide field. The observations were taken in seven nights in 2015
and 2016, resulting in 82 observed frames covering 3.6deg2. The data
reduction, image processing, and source extraction were performed in a
standard procedure using the ELIXIR pipeline and the ASTROMATIC
software, and eventually 351635 sources have been extracted. The data
quality is discussed in two regions (shallow and deep) separately, due
to the difference in the total integration time (4520 and 13910s). The
5σ limiting magnitude, seeing full width at half-maximum, and
the magnitude at 50 per cent completeness are 25.38mag (25.79mag in
the deep region), 0.82arcsec (0.94arcsec), and 25.06mag (25.45mag),
respectively. The u-band data provide us with critical improvements to
photometric redshifts and UV estimates of the precious infrared
sources from the AKARI space telescope.
Description:
The observations of the AKARI NEP field were made using the CFHT
MegaPrime/MegaCam with its u-band filter (u.MP9302; range
3041-4014Å; effective wavelength at 3610Å) in the CFHT Queued
Service Observations mode. The MegaPrime/MegaCam detector has 40 CCDs,
and each CCD is composed of 2048x4612 pixels with a pixel scale of
0.185arcsec. There were two observing runs. One was from 2015 May 22
to 26 and the other was from 2016 July 6 to 7 (PI: T. Goto). The total
observed area was about 3.6deg2. The former observation run
contained six observation pointings - NEP1, NEP2, NEP3, NEP4, NEP5,
and NEP6, while the latter had three - NEP1A, NEP1B, and NEP2A. The
NEP1, NEP2, NEP1A, NEP1B, and NEP2A pointings targeted the same
region, providing a total integration time of 13910s. The NEP3 and
NEP4, and the NEP5 and NEP6 pointings both have a 4520-s total
integration time.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 54 351635 A few rows of the u-band source catalogue
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- ID [1/351635] Source internal identifier
8- 18 F11.7 deg RAdeg Right ascension (J2000)
20- 29 F10.7 deg DEdeg Declination (J2000)
31- 37 F7.4 mag umag CFHT/MegaCam u-band AB magnitude
39- 45 F7.4 mag e_umag Error on umag
47- 51 F5.3 --- CS Star classifier based on the morphology of the
source
53- 54 I2 --- flag Source extraction flag (1)
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Note (1): 8-bit integer indicating if a source is extracted with warnings
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 01-Aug-2023