J/ApJ/834/160 ugriz colors of RR Lyrae stars in SDSS Stripe 82 (Ngeow+, 2017)
Period-color and amplitude-color relations at maximum and minimum light for
RR Lyrae stars in the SDSS Stripe 82 Region.
Ngeow C.-C., Kanbur S.M., Bhardwaj A., Schrecengost Z., Singh H.P.
<Astrophys. J., 834, 160-160 (2017)>
=2017ApJ...834..160N 2017ApJ...834..160N (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Photometry, SDSS ; Colors
Keywords: stars: atmospheres; stars: fundamental parameters;
stars: variables: RR Lyrae
Abstract:
Investigation of period-color (PC) and amplitude-color (AC) relations
at the maximum and minimum light can be used to probe the interaction
of the hydrogen ionization front (HIF) with the photosphere and the
radiation hydrodynamics of the outer envelopes of Cepheids and RR
Lyraes. For example, theoretical calculations indicated that such
interactions would occur at minimum light for RR Lyrae and result in a
flatter PC relation. In the past, the PC and AC relations have been
investigated by using either the (V-R)MACHO or (V-I) colors. In this
work, we extend previous work to other bands by analyzing the RR
Lyraes in the Sloan Digital Sky Survey Stripe 82 Region. Multi-epoch
data are available for RR Lyraes located within the footprint of the
Stripe 82 Region in five (ugriz) bands. We present the PC and AC
relations at maximum and minimum light in four colors: (u-g)0,
(g-r)0, (r-i)0, and (i-z)0, after they are corrected for
extinction. We found that the PC and AC relations for this sample of
RR Lyraes show a complex nature in the form of flat, linear or
quadratic relations. Furthermore, the PC relations at minimum light
for fundamental mode RR Lyrae stars are separated according to the
Oosterhoff type, especially in the (g-r)0 and (r-i)0 colors. If
only considering the results from linear regressions, our results are
quantitatively consistent with the theory of HIF-photosphere
interaction for both fundamental and first overtone RR Lyraes.
Description:
The ugriz band photometric light-curve data for RR Lyraes in the SDSS
Stripe 82 region was adopted from Sesar+ (2010, J/ApJ/708/717), who
found 483 RR Lyrae based on observations that spanned from 1998
September to 2007 November. Median numbers of data points per light
curve are 55 and 56 in uz bands and gri bands, respectively.
This set of RR Lyraes includes 379 fundamental mode RRab stars and 104
first overtone RRc stars. In addition to the light-curve data, Sesar+
(2010, J/ApJ/708/717) also provided the ugriz band template light
curves for RR Lyraes. We adopted these template light curves to derive
the amplitudes and colors at maximum and minimum light for each RR
Lyrae in the sample.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 85 398 Amplitudes and colors at the maximum and minimum
light for RR Lyrae stars in the sample
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See also:
J/AJ/130/1640 : Photom. of candidate RR Lyrae stars in the SDSS (Wu+, 2005)
J/AcA/59/1 : VI light curves of LMC RR Lyrae stars (Soszynski+, 2009)
J/MNRAS/398/1757 : RR Lyraes in SDSS stripe 82 (Watkins+, 2009)
J/ApJ/708/717 : Light curve templates of RR Lyrae stars (Sesar+, 2010)
J/MNRAS/424/2528 : RR Lyrae in SDSS Stripe 82 (Suveges+, 2012)
J/MNRAS/441/715 : Mid-infrared study of RR Lyrae stars (Gavrilchenko+, 2014)
J/MNRAS/441/1230 : RRLyr stars in the Catalins Sky Survey (CS2) (Abbas+, 2014)
http://www.astro.washington.edu/users/ivezic/sdss/catalogs/stripe82.html :
SDSS Stripe 82 Standard Star Catalog webpage
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- [SIG2010] RR Lyrae ID (Sesar+, 2010, J/ApJ/708/717)
10- 16 A7 --- Type RR Lyrae type (1)
18- 25 F8.5 [d] log(P) [-0.6/-0.08] log of Period
27- 31 F5.3 mag gAmp [0.2/1.7] g-band amplitude
33- 37 F5.3 mag (u-g)_MAX [0.9/1.3] Extinction corrected (u-g) color index
at maximum light
39- 44 F6.3 mag (g-r)_MAX [-0.3/0.2] Extinction corrected (g-r) color index
at maximum light
46- 51 F6.3 mag (r-i)_MAX [-0.3/0.07] Extinction corrected (r-i) color
index at maximum light
53- 58 F6.3 mag (i-z)_MAX [-0.2/0.09] Extinction corrected (i-z) color
index at maximum light
60- 64 F5.3 mag (u-g)_MIN [0.8/1.3] Extinction corrected (u-g) color index
at minimum light
66- 71 F6.3 mag (g-r)_MIN [-0.02/0.4] Extinction corrected (g-r) color
index at minimum light
73- 78 F6.3 mag (r-i)_MIN [-0.06/0.2] Extinction corrected (r-i) color
index at minimum light
80- 85 F6.3 mag (i-z)_MIN [-0.08/0.2] Extinction corrected (i-z) color
index at minimum light
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Note (1): RR Lyrae type as follows:
ab-OoI = Bailey type ab + Oosterhoff type I;
ab-OoII = Bailey type ab + Oosterhoff type II;
c = Bailey type c.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 10-Jul-2017