J/MNRAS/493/3293 New rotational periods of magnetic CP stars (Bernhard+, 2020)
New and improved rotational periods of magnetic CP stars from ASAS-3, KELT, and
MASCARA data.
Bernhard K., Hummerich S., Paunzen E.
<Mon. Not. R. Astron. Soc., 493, 3293-3330 (2020)>
=2020MNRAS.493.3293B 2020MNRAS.493.3293B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, peculiar ; Stars, variable ; Magnetic fields ;
Positional data ; Spectral types ; Photometry ; Optical
Keywords: stars: chemically peculiar - stars: rotation -
stars: variables: general
Abstract:
Magnetic chemically peculiar (mCP) stars allow the investigation of
such diverse phenomena as atomic diffusion, magnetic fields, and
stellar rotation. The aim of the present investigation is to enhance
our knowledge of the rotational properties of mCP stars by increasing
the sample of objects with accurately determined rotational periods.
To this end, archival photometric time-series data from the ASAS-3,
KELT, and MASCARA surveys were employed to improve existing rotational
period information and derive rotational periods for mCP stars
hitherto not known to be photometric variables. Our final sample
consists of 294 mCP stars, a considerable amount of which (more than
40 per cent) are presented here as photometric variables for the first
time. In addition, we identified 24 mCP star candidates that show
light variability in agreement with rotational modulation but lack
spectroscopic confirmation. The rotational period distribution of our
sample agrees well with the literature. Most stars are between 100Myr
and 1Gyr old, with an apparent lack of very young stars. No objects
were found on the zero-age main sequence; several stars seem to have
evolved to the subgiant stage, albeit well before the first dredge-up.
We identified four eclipsing binaries (HD 244391, HD 247441, HD 248784,
and HD 252519), which potentially host an mCP star. This is of great
interest because mCP stars are very rarely found in close binary
systems, particularly eclipsing ones. Using archival spectra, we find
strong evidence that the HD 252519 system indeed harbours an mCP star
component.
Description:
For the investigation with ASAS-3 and KELT data, a list of mCP stars
and mCP star candidates was selected from the most recent version of
the Catalogue of Ap, HgMn, and Am stars (Renson & Manfroid
2009A&A...498..961R 2009A&A...498..961R, Cat. III/260, RM09 hereafter). Here, the emphasis
was on deriving rotational periods for objects that hitherto lacked
this information; therefore, we excluded known ACV variables with
well-determined rotational periods from further analysis. To this end,
the General Catalogue of Variable Stars (Samus et al.
2017ARep...61...80S 2017ARep...61...80S, Cat. B/gcvs), the International Variable Star
Index of the AAVSO (VSX; Watson 2006SASS...25...47W 2006SASS...25...47W) and the SIMBAD
(Wenger et al. 2000A&AS..143....9W 2000A&AS..143....9W), and VizieR (Ochsenbein, Bauer &
Marcout 2000A&AS..143...23O 2000A&AS..143...23O) data bases were queried for
classificatory and rotational period information. Suspected or
misclassified variables and variables of undetermined type
(catalogue-types 'VAR', 'MISC', etc.) were kept. 112 mCP stars having
ASAS-3 data and 38 mCP stars with KELT data were selected via this
approach (see Table A1).
At the time of this writing, MASCARA data were only publicly available
for the stars studied by Burggraaff et al. (2018A&A...617A..32B 2018A&A...617A..32B, Cat.
J/A+A/617/A32). We cross-matched the light curves published by
Burggraaff et al. (2018A&A...617A..32B 2018A&A...617A..32B, Cat. J/A+A/617/A32) with the
RM09 catalogue and retrieved data for 144 mCP stars (see Table A2).
All of these bright objects are already known as photometric variables
with period information of differing quality. Therefore, because of
their high quality and cadence, MASCARA data were employed to verify
or improve the published periods.
Finally, 24 stars that show light variability in agreement with
rotational modulation were selected and included into the sample as
ACV candidates (see Table 3). Spectroscopic confirmation of their
suspected mCP star status is needed.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3.dat 146 24 Essential data for the ACV variable candidates
identified among stars of other CP subclasses or
stars from RM09 with non-peculiar
classifications
tablea1.dat 150 150 Essential data for the mostly new ACV variables
analysed with ASAS-3 and KELT data
tablea2.dat 145 144 Essential data for the known ACV variables whose
rotational periods were investigated with
MASCARA data
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See also:
III/260 : General Catalogue of Ap and Am stars (Renson+ 2009)
B/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)
J/A+A/617/A32 : MASCARA bright variable stars light curves (Burggraaff+, 2018)
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Survey Survey source (KELT or MASCARA)
9- 23 A15 --- Name Variable candidate name (HD NNNNNN or
TYC FFF-NNNNN-N)
25 A1 --- f_Name [ab] Flag on Name (1)
27- 31 I5 --- ID Identification number from Renson & Manfroid
(2009A&A...498..961R 2009A&A...498..961R, Cat III/260)
33- 34 I2 h RAh Right ascension (J2000)
36- 37 I2 min RAm Right ascension (J2000)
39- 43 F5.2 s RAs Right ascension (J2000)
45 A1 --- DE- Declination sign (J2000)
46- 47 I2 deg DEd Declination (J2000)
49- 50 I2 arcmin DEm Declination (J2000)
52- 55 F4.1 arcsec DEs Declination (J2000)
57- 64 A8 --- SpType Spectral type from Renson & Manfroid
(2009A&A...498..961R 2009A&A...498..961R, Cat III/260)
66- 70 F5.2 mag Vmagmin V-band magnitude (minimum value)
72- 76 F5.2 mag Vmagmax V-band magnitude (maximum value)
78- 85 F8.5 d Period Period derived in this work
87- 93 F7.5 d e_Period Error on Period
95-102 F8.3 d Epoch Epoch (HJD-2450000)
104-108 F5.3 d e_Epoch Error on Epoch
110-114 F5.3 mag A1 Semi-amplitude of the fundamental variation
116-120 F5.3 mag A2 Semi-amplitude of the first harmonic
variation
122-126 F5.3 rad Phi1 Phase of the fundamental variation
128-132 F5.3 rad Phi2 Phase of the first harmonic variation
134-139 F6.3 mag Gmag Gaia DR2 G-band magnitude
141-146 F6.3 mag BP-RP Gaia DR2 BP-RP colour
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Note (1): Flag as follows:
a = NSV 2132; suspected of variability by Crawford (1963ApJ...137..530C 1963ApJ...137..530C);
non-variable according to the VSX
b = NSV 25432; possible microvariable according to Rufener
(1981A&AS...45..207R 1981A&AS...45..207R); V-magnitude range is 6.74-6.76mag according to
the VSX
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 A1 --- Survey [AK] Survey source (A: ASAS-3; K: KELT)
3- 17 A15 --- Name Variable candidate name (HD NNNNNN or
TYC FFF-NNNNN-N)
19 A1 --- f_Name Flag on Name (1)
21 A1 --- binary [*] Indicates the source is one of the four
binary systems in the sample
23- 27 I5 --- ID Identification number from Renson & Manfroid
(2009A&A...498..961R 2009A&A...498..961R, Cat III/260)
29- 30 I2 h RAh Right ascension (J2000)
32- 33 I2 min RAm Right ascension (J2000)
35- 39 F5.2 s RAs Right ascension (J2000)
41 A1 --- DE- Declination sign (J2000)
42- 43 I2 deg DEd Declination (J2000)
45- 46 I2 arcmin DEm Declination (J2000)
48- 51 F4.1 arcsec DEs Declination (J2000)
53- 63 A11 --- SpType Spectral type from Renson & Manfroid
(2009A&A...498..961R 2009A&A...498..961R, Cat III/260)
65- 69 F5.2 mag Vmagmin V-band magnitude (minimum value)
71 A1 --- l_Vmagmax Limit flag on Vmagmax
73- 77 F5.2 mag Vmagmax V-band magnitude (maximum value)
79- 88 F10.6 d Period Period derived in this work
90- 97 F8.6 d e_Period Error on Period
99-106 F8.3 d Epoch Epoch (HJD-2450000)
108-112 F5.3 d e_Epoch Error on Epoch
114-118 F5.3 mag A1 ? Semi-amplitude of the fundamental variation
120-124 F5.3 mag A2 ? Semi-amplitude of the first harmonic
variation
126-130 F5.3 rad Phi1 ? Phase of the fundamental variation
132-136 F5.3 rad Phi2 ? Phase of the first harmonic variation
138-143 F6.3 mag Gmag Gaia DR2 G-band magnitude
145-150 F6.3 mag BP-RP Gaia DR2 BP-RP colour
--------------------------------------------------------------------------------
Note (1): Flag as follows:
a = NSV 16014 (ACV:)
b = ASAS J055659-0345.3 (MISC; PVSX=1.781649d)
c = HIP 29253 (VAR; PVSX=5.07872d)
d = ASAS J061114+0351.8 (EC|ESD; PVSX=1.9014d)
e = NSV 16881 (VAR:)
f = ASAS J071051-1428.1 (DCEP-FO|ESD; PVSX=1.09015d)
g = ASAS J075249-4937.5 (ESD|DCEP-FU|ED; PVSX=4.3169d)
h = HIP 49373 (VAR; PVSX=3.30513d)
i = HIP 50578 (VAR; PVSX=2.12287d)
j = HIP 53684 (VAR; PVSX=0.97435d)
k = HIP 56269 (VAR; PVSX=0.49205d)
l = ASAS J114101-6036.8 (MISC; PVSX=4.4110d)
m = HIP 57987 (VAR; PVSX=1.67687d)
n = ASAS J124145-6241.4 (VAR; PVSX=21.318367d)
o = NSV 19772 (VAR:)
p = NSV 19966 (VAR:)
q = NSV 20024 (VAR:)
r = NSV 20059 (VAR:)
s = HIP 72159 (VAR; PVSX=1.35579d)
t = NSV 20254 (VAR:)
u = EPIC 202727506 (VAR; PVSX=1.275979d)
v = ASAS J172938-3546.4 (ACV|ESD; PVSX=2.682024d)
w = ASAS J175155-3505.0 (VAR)
x = NSV 24422 (no type and period given)
y = HIP 96290 (VAR; PVSX=0.08582d)
z = HD 247441 (EA; PVSX=4.2676d)
$ = HIP 101323 (SPB; PVSX=1.09613d)
+ = NSV 13774 (no type and period given)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Variable candidate name (HD NNNNNN)
11- 15 I5 --- ID Identification number from Renson & Manfroid
(2009A&A...498..961R 2009A&A...498..961R, Cat III/260)
17- 18 I2 h RAh Right ascension (J2000)
20- 21 I2 min RAm Right ascension (J2000)
23- 27 F5.2 s RAs Right ascension (J2000)
29 A1 --- DE- Declination sign (J2000)
30- 31 I2 deg DEd Declination (J2000)
33- 34 I2 arcmin DEm Declination (J2000)
36- 39 F4.1 arcsec DEs Declination (J2000)
41- 52 A12 --- SpType Spectral type from Renson & Manfroid
(2009A&A...498..961R 2009A&A...498..961R, Cat III/260)
54- 57 F4.2 mag Vmagmin V-band magnitude (minimum value)
59- 62 F4.2 mag Vmagmax V-band magnitude (maximum value)
64- 74 F11.8 d PVSX Period from literature
76- 84 F9.6 d Period Period derived in this work
86- 93 F8.6 d e_Period Error on Period
95-102 F8.3 d Epoch Epoch (HJD-2450000)
104-108 F5.3 d e_Epoch Error on Epoch
110-114 F5.3 mag A1 Semi-amplitude of the fundamental variation
116-120 F5.3 mag A2 Semi-amplitude of the first harmonic
variation
122-126 F5.3 rad Phi1 Phase of the fundamental variation
128-132 F5.3 rad Phi2 Phase of the first harmonic variation
134-138 F5.3 mag Gmag ? Gaia DR2 G-band magnitude
140-145 F6.3 mag BP-RP ? Gaia DR2 BP-RP colour
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 21-Apr-2023