J/AJ/147/128 HAT-P-44, HAT-P-45, and HAT-P-46 follow-up (Hartman+, 2014)
HAT-P-44b, HAT-P-45b, and HAT-P-46b: three transiting hot jupiters in possible
multi-planet systems.
Hartman J.D., Bakos G.A., Torres G., Kovacs G., Johnson J.A., Howard A.W.,
Marcy G.W., Latham D.W., Bieryla A., Buchhave L.A., Bhatti W., Beky B.,
Csubry Z., Penev K., de Val-Borro M., Noyes R.W., Fischer D.A.,
Esquerdo G.A., Everett M., Szklenar T., Zhou G., Bayliss D., Shporer A.,
Fulton B.J., Sanchis-Ojeda R., Falco E., Lazar J., Papp I., Sari P.
<Astron. J., 147, 128 (2014)>
=2014AJ....147..128H 2014AJ....147..128H
ADC_Keywords: Planets ; Stars, double and multiple ; Photometry ; Spectroscopy ;
Radial velocities
Keywords: planetary systems - stars: individual: (HAT-P-44,HAT-P-45,HAT-P-46) -
techniques: photometric - techniques: spectroscopic
Abstract:
We report the discovery by the HATNet survey of three new transiting
extrasolar planets orbiting moderately bright (V=13.2, 12.8, and 11.9)
stars. The planets have orbital periods of 4.3012, 3.1290, and 4.4631
days, masses of 0.35, 0.89, and 0.49MJ, and radii of 1.24, 1.43, and
1.28RJ. The stellar hosts have masses of 0.94, 1.26, and
1.28M☉. Each system shows significant systematic variations in
its residual radial velocities, indicating the possible presence of
additional components. Based on its Bayesian evidence, the preferred
model for HAT-P-44 consists of two planets, including the transiting
component, with the outer planet having a period of 872 days,
eccentricity of 0.494±0.081, and a minimum mass of 4.0MJ. Due to
aliasing we cannot rule out alternative solutions for the outer planet
having a period of 220 days or 438 days. For HAT-P-45, at present
there is not enough data to justify the additional free parameters
included in a multi-planet model; in this case a single-planet
solution is preferred, but the required jitter of 22.5±6.3m/s is
relatively high for a star of this type. For HAT-P-46 the preferred
solution includes a second planet having a period of 78 days and a
minimum mass of 2.0MJ, however the preference for this model over a
single-planet model is not very strong. While substantial
uncertainties remain as to the presence and/or properties of the outer
planetary companions in these systems, the inner transiting planets
are well characterized with measured properties that are fairly robust
against changes in the assumed models for the outer planets. Continued
radial velocity monitoring is necessary to fully characterize these
three planetary systems, the properties of which may have important
implications for understanding the formation of hot Jupiters.
Description:
The planets presented in this paper were first identified based on
data from the HATNet telescopes. HAT-P-44 was observed between 2006
Jan and 2006 Jul using the HAT-5w telescope, and between 2010 Apr and
2010 Jul with the HAT-6 telescope. HAT-P-45 and HAT-P-46 were observed
between 2010 Sep and 2010 Oct with the HAT-5 telescope, and between
2010 Apr and 2010 Oct with the HAT-8 telescope.
Additional photometric observations (Tables 6-8) of each of the
transiting planet systems were obtained using the following
facilities: the KeplerCam CCD camera on the FLWO 1.2m telescope
(HAT-P-44 on 2011 Apr 14 and 2011 May 27; HAT-P-45 on 2011 Apr 02,
2011 Apr 05, 2011 May 22, 2011 Jun 10, 2011 Jul 05, and 2013 May 20;
HAT-P-46 on 2011 May 05, 2011 May 14, and 2011 May 23), the CCD imager
on the 0.8m remotely operated Byrne Observatory at Sedgwick (BOS)
reserve in California (HAT-P-44 on 2011 Apr 14), and the Spectral
Instrument CCD on the 2.0m Faulkes Telescope North (FTN) at Haleakala
Observatory in Hawaii (HAT-P-45 on 2011 Apr 30). Both BOS and FTN are
operated by the Las Cumbres Observatory Global Telescope (LCOGT).
High-resolution, low-S/N "reconnaissance" spectra were obtained for
HAT-P-44, HAT-P-45, and HAT-P-46 using the Tillinghast Reflector
Echelle Spectrograph (TRES) on the 1.5m Tillinghast Reflector at Fred
Lawrence Whipple Observatory (FLWO) in Arizona. Medium-resolution
reconnaissance spectra were also obtained for HAT-P-45 and HAT-P-46
using the Wide Field Spectrograph (WiFeS) on the ANU 2.3m telescope at
Siding Spring Observatory.
We obtained high-resolution, high-S/N spectra (Tables 3-5) of each of
these objects using HIRES on the Keck-I telescope in Hawaii.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 35 3 Stars observed
table3.dat 52 23 Relative radial velocities, bisector spans, and
activity index measurements of HAT-P-44
table4.dat 52 12 Relative radial velocities, bisector spans, and
activity index measurements of HAT-P-45
table5.dat 52 13 Relative radial velocities, bisector spans, and
activity index measurements of HAT-P-46
table6.dat 39 548 High-precision differential photometry of HAT-P-44
table7.dat 39 1021 High-precision differential photometry of HAT-P-45
table8.dat 39 992 High-precision differential photometry of HAT-P-46
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See also:
J/AJ/146/113 : Differential griz photometry of HATS-3 (Bayliss+, 2013)
J/ApJ/749/134 : HAT-P-17 radial velocities and light curves (Howard+, 2012)
J/AJ/144/139 : HAT-P-39, HAT-P-40, and HAT-P-41 follow-up (Hartman+, 2012)
J/ApJ/745/80 : HAT-P-25 differential photometry (Quinn+, 2012)
J/AJ/144/19 : Follow-up photometry for HAT-P-34--HAT-P-37 (Bakos+, 2012)
J/ApJ/726/52 : HAT-P-18 and HAT-P-19 follow-up (Hartman+, 2011)
J/PASP/123/412 : Exoplanet Orbit Database (Wright+, 2011)
J/ApJ/720/1118 : i-band photometry of HAT-P-16 (Buchhave+, 2010)
J/ApJ/710/1724 : Follow-up photometry for HAT-P-11 (Bakos+, 2010)
J/ApJ/725/875 : Chromospheric activity for CPS stars (Isaacson+, 2010)
J/ApJ/707/446 : HAT-P-13 photometry follow-up (Bakos+, 2009)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- HAT-P [44/46] HAT name of the host planet
4- 5 I2 h RAh Hour of Right Ascension (J2000) (1)
7- 8 I2 min RAm Minute of Right Ascension (J2000) (1)
10- 14 F5.2 s RAs Second of Right Ascension (J2000) (1)
16 A1 --- DE- Sign of the Declination (J2000) (1)
17- 18 I2 deg DEd Degree of Declination (J2000) (1)
20- 21 I2 arcmin DEm Arcminute of Declination (J2000) (1)
23- 26 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
28- 35 F8.6 d Per Period
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Note (1): From SIMBAD database (http://simbad.u-strasbg.fr/simbad/).
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Byte-by-byte Description of file: table[345].dat
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Bytes Format Units Label Explanations
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1- 10 F10.5 d BJD Barycentric Julian Date (BJD-2454000) (G1)
12- 18 F7.2 m/s RV [-128.98/124.79]? Radial velocity (1)
20 A1 --- f_RV [a] Iodine-free template exposure (2)
22- 26 F5.2 m/s e_RV ? The 1σ uncertainty in RV (3)
28- 33 F6.2 m/s BS Bissector span measurement
35- 39 F5.2 m/s e_BS The 1σ uncertainty in BS
41- 46 F6.4 --- S ? Chromospheric activity index (4)
48- 52 F5.3 --- Phase [0/1] Phase
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Note (1): The zero point of these velocities is arbitrary. An overall offset
γrel fitted to these velocities in Section 3.4 has not been
subtracted.
Note (2): For the iodine-free template exposures we do not measure the RV but do
measure the BS and S index. Such template exposures can be distinguished by
the missing RV value.
Note (3): Internal errors excluding the component of astrophysical jitter
considered in Section 3.4. The formal errors are likely underestimated in
cases where σRV>10m/s, as the HIRES Doppler code is not reliable
for low S/N observations.
Note (4): Computed as in Isaacson & Fischer (2010, cat. J/ApJ/725/875).
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Byte-by-byte Description of file: table[678].dat
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Bytes Format Units Label Explanations
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1- 11 F11.5 d BJD Barycentric Julian Date (BJD-2400000) (G1)
13- 20 F8.5 mag Dmag Processed differential magnitude in Flt (1)
22- 28 F7.5 mag e_Dmag The 1σ error in mag
30- 37 F8.5 mag Ormag Original raw magnitude in Flt (2)
39 A1 --- Flt [gri] Filter used (Sloan g, Sloan i, Sloan r)
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Note (1): The out-of-transit level has been subtracted. These magnitudes have
been subjected to the External Parameter Decorrelation (EPD; Bakos et al.,
2010, cat. J/ApJ/710/1724) and Trend Filtering Algorithm (TFA; see Kovacs
et al., 2005MNRAS.356..557K 2005MNRAS.356..557K) procedures, carried out simultaneously with
the transit fit.
Note (2): Magnitude values without application of the EPD and TFA procedures.
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Global notes:
Note (G1): Calculated directly from UTC, without correction for leap seconds.
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 22-Sep-2014