J/A+A/666/A155 TOI-1468 photometry and radial velocities (Chaturvedi+, 2022)
TOI-1468: A system of two transiting planets, a super-Earth and
a mini-Neptune, on opposite sides of the radius valley.
Chaturvedi P., Bluhm P., Nagel E., Hatzes A.P., Morello G., Brady M.,
Korth J., Molaverdikhani K., Kossakowski D., Caballero J.A., Guenther E.W.,
Palle E., Espinoza N., Seifahrt A., Lodieu N., Cifuentes C., Furlan E.,
Amado P.J., Barclay T., Bean J., Bejar V.J.S., Bergond G., Boyle A.W.,
Ciardi D., Collins K.A., Collins K.I., Esparza-Borges E., Fukui A.,
Gnilka C.L., Goeke R., Guerra P., Henning T., Herrero E., Howell S.B.,
Jeffers S.V., Jenkins J.M., Jensen E.L.N., Kasper D., Kodama T.,
Latham D.W., Lopez-Gonzalez M.J., Luque R., Montes D., Morales J.C.,
Mori M., Murgas F., Narita N., Nowak G., Parviainen H., Passegger V.M.,
Quirrenbach A., Reffert S., Reiners A., Ribas I., Ricker G.R., Rodriguez E.,
Rodriguez-Lopez C., Schlecker M., Schwarz R.P., Schweitzer A., Seager S.,
Stefansson G., Stockdale C., Tal-Or L., Twicken J.D., Vanaverbeke S.,
Wang G., Watanabe D., Winn J.N., Zechmeister M.
<Astron. Astrophys. 666, A155 (2022)>
=2022A&A...666A.155C 2022A&A...666A.155C (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Photometry ; Optical ;
Radial velocities
Keywords: techniques: photometric - techniques: radial velocities -
stars: individual: TOI-1468 - stars: late-type
Abstract:
We report the discovery and characterization of two small transiting
planets orbiting the bright M3.0 V star TOI-1468 (LSPM J0106+1913),
whose transit signals were detected in the photometric time series in
three sectors of the TESS mission. We confirm the planetary nature of
both of them using precise radial velocity measurements from the
CARMENES and MAROON-X spectrographs, and supplemented it with
ground-based transit photometry. A joint analysis of all these data
reveals that the shorter-period planet, TOI-1468b (Pb=1.88d), has a
planetary mass of Mb= 3.21±0.24M_{earth} and a radius of
Rb=1.280^+0.038-0.039R_{earth}, resulting in a density of
rhob=8.39^+ 1.05-0.92_g/cm3, which is consistent with a mostly
rocky composition. For the outer planet, TOI-1468c (Pc=15.53d), we
derive a mass of Mc=6.64^+ 0.67^-0.68M_{earth}, a radius of
Rc=2.06±0.04R_{earth}, and a bulk density of rhoc=2.00^+
0.21-0.19_g/cm3, which corresponds to a rocky core composition
with a H/He gas envelope. These planets are located on the opposite
sides of the radius valley, making our system an interesting discovery
as there are only a handful of other systems with the same properties.
This finding can then further help determine a more precise location
of the radius valley for small planets around M dwarfs and, therefore,
shed more light on planet formation and evolution scenarios.
Description:
We tabulated the transits observed with several ground-based
photometry for TOI-1468 in the file table2.dat, the radial velocities
and spectroscopic activity indicators for TOI-1468 observed with the
CARMENES spectrograph in the file tableb2.dat, and the radial velocity
measurements and spectroscopic activity indicators for TOI-1468 from
the blue and red arms for MAROON-X spectra in the file tableb3.dat.
Objects:
------------------------------------------------------
RA (2000) DE Designation(s)
------------------------------------------------------
01 06 36.98 +19 13 33.2 TOI-1468 = LSPM J0106+1913
------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 97 20 Ground-based observations of TOI-1468 transits
tableb2.dat 89 65 CARMENES radial velocities and spectroscopic
activity indicators
tableb3.dat 92 32 MAROON-X radial velocities and spectroscopic
activity indicators each for the blue and red
arms respectively
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Planet Transiting planet TOI-1468b or TOI-1468c
11- 27 A17 --- Tel Ground-based facility used for the
transit observations
29- 48 A20 --- Inst Transit detecting instrument
50- 58 A9 --- Filter Filter used for making the
transit observations
60- 64 F5.3 arcsec/pix scale Instrument pixel scale
66- 70 F5.2 arcsec PSF ?=- Point Spread Function
71 A1 --- n_PSF [c]
73- 76 F4.1 pix apRad ?=- Radius of the photometric aperture
78- 87 A10 "date" Date Observation date
89- 93 F5.1 min Dur Transit duration
95- 97 A3 --- Dataset [Yes ] Datasets finally used for the
analysis
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tableb2.dat tableb3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 F13.5 d BJD Barycentric Julian date in the barycentric
dynamical time standard
15- 20 F6.2 m/s RV Radial velocity
22- 25 F4.2 m/s e_RV rms uncertainty on Radial velocity
27- 31 F5.3 --- CaII-IRT1 ?=- CaII IRT1 activity indicator
33- 37 F5.3 --- e_CaII-IRT1 ?=- rms uncertainty on CaII-IRT1
39- 44 F6.2 m/s CRX Chromatic index (m/(s.Np) unit)
46- 50 F5.2 m/s e_CRX rms uncertainty on CRX (m/(s.Np) unit)
52- 57 F6.2 m2/s2 dLW Differential line width
59- 63 F5.2 m2/s2 e_dLW rms uncertainty on dLW
65- 69 F5.3 --- Halpha FWHM Hα activity indicator
71- 75 F5.3 --- e_Halpha rms uncertainty on Halpha
77- 81 F5.3 --- NaI-D2 ?=- NaI-D2 activity indicator
83- 87 F5.3 --- e_NaI-D2 ?=- rms uncertainty on NaI-D2
89- 92 A4 --- Arm [Blue Red] Arm for tableb3.dat only
--------------------------------------------------------------------------------
Acknowledgements:
Priyanka Chaturvedi, priyanka(at)tls-tautenburg.de
(End) Patricia Vannier [CDS] 10-Aug-2022