J/AJ/152/91 Faint UBVRI standard stars at +50° declination (Clem+, 2016)
Faint UBVRI standard star fields at +50deg declination.
Clem J.L., Landolt A.U.
<Astron. J., 152, 91-91 (2016)>
=2016AJ....152...91C 2016AJ....152...91C (SIMBAD/NED BibCode)
ADC_Keywords: Stars, standard ; Photometry, UBVRI ; Photometry, CCD
Keywords: catalogs - standards - stars: fundamental parameters -
techniques: photometric
Abstract:
Precise and accurate CCD-based UBVRI photometry is presented for ∼2000
stars distributed around the sky in a declination zone centered
approximately at +50°. Their photometry has been calibrated to the
standard Johnson UBV and Kron-Cousins RI systems through observations
of the UBVRI standard stars presented in the various works of Landolt.
The magnitude and color range for these stars are 12≲V≲22 and
-0.3≲(B-V)≲1.8, respectively. Each star averages 13 measures in each
UBVRI filter from data taken on 41 different photometric nights
obtained over a 21 month period. Hence, there now exists a network of
faint UBVRI photometric standard stars centered on the declination
zones δ=-50°, 0°, and +50°.
Description:
All of the data presented herein were obtained at the 2.1m telescope
at the Kitt Peak National Observatory (KPNO) over 122 nights assigned
in the time period between 2012 October and 2014 June, inclusive.
Two different detectors, dubbed "STA2" and "STA3," were available
during the observing campaign. The STA2 chip operated on the telescope
for 14 of our nights in late 2012 before it experienced an unexpected
failure that forced it into early retirement. Consequently, it was
replaced with STA3, which was used for the remainder of the program.
STA2 and STA3 were identical twins in regards to their physical
characteristics (size=2000*1300pixels; pixel size=24µm; pixel
scale=0.304''/pixel; field of view≃10.1'*6.6').
Our final photometric database contains a total of 2125 new standard
stars distributed among 12 different fields centered on +50°
declination listed in Table2. It is important to note that stars in
the fields GD277, GD421, SA23, PG1430+427, PG1648+536, and SA41 failed
to pass our culling process due to the fact they were observed too few
times in each filter. Individual data tables containing the
photometric and astrometric results for each of the 12 fields are
provided in Table6. The photometry has been calibrated to the standard
Johnson UBV and Kron-Cousins RI systems through observations of the
UBVRI standard stars presented in the various works of Landolt.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 50 18 Program fields
table6.dat 197 2125 UBVRI photometry and astrometry for stars in
each of the 12 fields
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See also:
II/183 : UBVRI Photometric Standards (Landolt 1992)
II/118 : UBVRI standards around Celestial Equator (Landolt 1983)
J/AJ/146/131 : UBVRI standard stars at +50° declination (Landolt, 2013)
J/AJ/146/88 : UBVRI standard stars around the celestial equator (Clem+, 2013)
J/AJ/137/4186 : UBVRI standards around celestial equator (Landolt, 2009)
J/AJ/133/2502 : UBVRI Standard Stars (Landolt, 2007)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Field Field name
16- 17 I2 h RAh Hour of Right Ascension (J2000)
19- 20 I2 min RAm Minute of Right Ascension (J2000)
22- 25 F4.1 s RAs Second of RIght Ascension (J2000)
27 A1 --- DE- Sign of the Declination (J2000)
28- 29 I2 deg DEd Degree of Declination (J2000)
31- 32 I2 arcmin DEm Arcminute of Declination (J2000)
34- 35 I2 arcsec DEs Arcsecond of Declination (J2000)
37- 38 I2 --- NU [1/23] Number of exposures obtained in U filter (1)
40- 41 I2 --- NB [1/24] Number of exposures obtained in B filter (1)
43- 44 I2 --- NV [1/27] Number of exposures obtained in V filter (1)
46- 47 I2 --- NR [1/24] Number of exposures obtained in R filter (1)
49- 50 I2 --- NI [1/23] Number of exposures obtained in I filter (1)
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Note (1): Over the course of our observing runs at the KPNO 2.1m.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Field Field identifier
16- 18 I3 --- Star [1/401] Sequential star number within Field
20- 21 I2 h RAh Hour of Right Ascension (J2000)
23- 24 I2 min RAm Minute of Right Ascension (J2000)
26- 30 F5.2 s RAs Second of Right Ascension (J2000)
32 A1 --- DE- Sign of the Declination (J2000)
33- 34 I2 deg DEd Degree of Declination (J2000)
36- 37 I2 arcmin DEm Arcminute of Declination (J2000)
39- 42 F4.1 arcsec DEs Arcsecond of Declination (J2000)
44- 49 F6.3 mag Umag [11.9/24] The U band magnitude
51- 56 F6.4 mag e_Umag [0.0008/0.1] Uncertainty in Umag
58- 59 I2 --- o_Umag [3/23] Number of measurements in Umag
61- 66 F6.3 mag Bmag [11.4/23.7] The B band magnitude
68- 73 F6.4 mag e_Bmag [0.0007/0.06] Uncertainty in Bmag
75- 76 I2 --- o_Bmag [4/24] Number of measurements in Bmag
78- 83 F6.3 mag Vmag [10.3/23] The V band magnitude
85- 90 F6.4 mag e_Vmag [0.0009/0.041] Uncertainty in Vmag
92- 93 I2 --- o_Vmag [4/27] Number of measurements in Vmag
95-100 F6.3 mag Rmag [9.7/22.9] The R band magnitude
102-107 F6.4 mag e_Rmag [0.0007/0.07] Uncertainty in Rmag
109-110 I2 --- o_Rmag [5/24] Number of measurements in Rmag
112-117 F6.3 mag Imag [9.1/22.9] The I band magnitude
119-124 F6.4 mag e_Imag [0.001/0.091] Uncertainty in Imag
126-127 I2 --- o_Imag [3/23] Number of measurements in Imag
129-134 F6.3 mag U-B [-1.2/3.5] The (U-B) color index
136-141 F6.4 mag e_U-B [0.0012/0.12] Uncertainty in U-B (1)
143-148 F6.3 mag B-V [-0.31/3.069] The (B-V) color index
150-155 F6.4 mag e_B-V [0.0014/0.06] Uncertainty in B-V (2)
157-162 F6.3 mag V-R [-0.15/2] The (V-R) color index
164-169 F6.4 mag e_V-R [0.001/0.071] Uncertainty in V-R (3)
171-176 F6.3 mag R-I [-0.18/1.9] The (R-I) color index
178-183 F6.4 mag e_R-I [0.001/0.1] Uncertainty in R-I (4)
185-190 F6.3 mag V-I [-0.33/3.8] The (V-I) color index
192-197 F6.4 mag e_V-I [0.001/0.095] Uncertainty in V-I (5)
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Note (1): (σ2U+σ2B)1/2.
Note (2): (σ2B+σ2V)1/2.
Note (3): (σ2V+σ2R)1/2.
Note (4): (σ2R+σ2I)1/2.
Note (5): (σ2V+σ2I)1/2.
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 27-Oct-2016