J/AJ/168/116 NEID radial velocities of TOI-5126 and TOI-5398 (Radzom+, 2024)
Evidence for primordial alignment: insights from stellar obliquity measurements
for compact sub-Saturn systems.
Radzom B.T., Dong J., Rice M., Wang X.-Y., Yee S.W., Fairnington T.R.,
Petrovich C., Wang S.
<Astron. J., 168, 116 (2024)>
=2024AJ....168..116R 2024AJ....168..116R
ADC_Keywords: Radial velocities; Exoplanets; Spectra, optical
Keywords: Exoplanet astronomy ; Exoplanet dynamics ; Exoplanet evolution ;
Extrasolar gaseous giant planets ; Radial velocity ; Transits
Abstract:
Despite decades of effort, the mechanisms by which the spin axis of a
star and the orbital axes of its planets become misaligned remain
elusive. In particular, it is of great interest whether the large
spin-orbit misalignments observed are driven primarily by
high-eccentricity migration-expected to have occurred for
short-period, isolated planets-or reflect a more universal process
that operates across systems with a variety of present-day
architectures. Compact multiplanet systems offer a unique opportunity
to differentiate between these competing hypotheses, as their tightly
packed configurations preclude violent dynamical histories, including
high-eccentricity migration, allowing them to trace the primordial
disk plane. In this context, we report measurements of the
sky-projected stellar obliquity (λ) via the Rossiter-McLaughlin
effect for two sub-Saturns in multiple- transiting systems: TOI-5126 b
(λ=1±48°) and TOI-5398 b (λ=-8.1-6.3+5.3°).
Both are spin-orbit aligned, joining a fast-growing group of just
three other compact sub-Saturn systems, all of which exhibit
spin-orbit alignment. In aggregate with archival data, our results
strongly suggest that sub-Saturn systems are primordially aligned and
become misaligned largely in the postdisk phase, as appears to be the
case increasingly for other exoplanet populations.
Description:
The Rossiter-McLaughlin (RM) effects of TOI-5126 and TOI-5398 were
observed using the WIYN/NEID spectrograph in high resolution (HR) mode
(R∼110000) on 2023 February 28 and 2023 April 16, respectively
(wavelength coverage of 380-930nm).
Objects:
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RA (ICRS) DE Designation(s) (Pb)
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10 47 31.09 +36 19 45.8 TOI 5398 = TYC 2518-317-1 (Pb=10.5905)
10 06 38.40 +18 38 02.7 TOI 5126 = TYC 1415-1408-1 (Pb=5.45886)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig1.dat 69 48 NEID radial velocities of TOI-5126 and TOI-5398
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/328 : AllWISE Data Release (Cutri+ 2013)
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
J/ApJ/723/L223 : Radial velocities of HAT-P-11 (Winn+, 2010)
J/ApJ/757/18 : RVs for 16 hot Jupiter host stars (Albrecht+, 2012)
J/ApJ/771/129 : Submillimetric Class II sources of Taurus (Andrews+, 2013)
J/ApJ/780/159 : Rot-mass-age relationship of old field stars (Epstein+, 2014)
J/ApJ/828/46 : ALMA survey of Lupus protopl. disks. I. (Ansdell+, 2016)
J/ApJ/831/125 : ALMA 887um obs. of ChaI star-forming region (Pascucci+, 2016)
J/A+A/608/A135 : Sodium detection in WASP-69b atm. (Casasayas-Barris+, 2017)
J/ApJ/834/17 : Mass & radius of planets, moons, low mass stars (Chen+, 2017)
J/ApJ/860/109 : Keck HIRES obs. of subgiants (retired A stars) (Ghezzi+, 2018)
J/A+A/613/A41 : 5 exoplanet light and RV curves (Mancini+, 2018)
J/AJ/160/192 : Photometry and RVs of K2-25b with HPF (Stefansson+, 2020)
J/other/ExA/51.109 : Transit KELT-11b observed by CHEOPS (Benz+, 2021)
J/A+A/645/A106 : Atomic data for the Gaia-ESO Survey (Heiter+, 2021)
J/AJ/162/263 : TESS nearby planetary companions to hot Jupiters (Hord+, 2021)
J/AJ/161/68 : Obliquities of hot Kepler hosting stars (Louden+, 2021)
J/AJ/161/119 : The TESS-Keck survey. IV. Rvel for WASP-107 (Rubenzahl+, 2021)
J/AJ/164/26 : Hot Jupiters isochrones & stellar modeling (Hamer+, 2022)
J/AJ/163/247 : HIRES, PEPSI & TRES RVs of V1298 Tau (Johnson+, 2022)
J/AJ/164/104 : NEID and HIRES radial velocity of TOI-1478 (Rice+, 2022)
J/ApJ/926/L8 : Spectroscopic and transit obs. of WASP-148 (Wang+, 2022)
J/AJ/165/33 : HIRES TOI-1136s planets & planet b RVels (Dai+, 2023)
J/AJ/166/266 : Photometry obtained for TOI-2202b (Rice+, 2023)
J/AJ/167/175 : Radial velocity and photometry of TOI-677 (Hu+, 2024)
J/A+A/682/A129 : TOI-5398 spectroscopic time-series (Mantovan+, 2024)
J/A+A/684/L17 : TOI-5398 radial velocity curve (Mantovan+, 2024)
Byte-by-byte Description of file: fig1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- ID Identifier ("TOI 5126" or "TOI 5398")
10- 12 A3 --- Transit In or out of transit (1)
14- 26 F13.5 d BJD Barycentric Julian date of mid-point
28- 34 F7.4 km/s RVel [-9.65/12.42] Radial velocity (2)
36- 41 F6.4 km/s e_RVel [0.003/0.02] Uncertainty in RVel
43- 55 F13.5 d b_BJD Start time of RVel observation
57- 69 F13.5 d B_BJD End time of RVel observation
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Note (1): Note that the NEID RV measurement obtained ∼1h prior to ingress
for TOI 5398 b was taken on April 10, 2022 via 300-second exposure
as part of our out-of-transit follow-up for this system.
Note (2): The conversion from the measured RVs in km/s to the m/s RVs
displayed in Figure 1 is as follows:
For TOI 5126, we subtracted a quadratic RV offset of the form
a + b * x + c * x2, where x is time (normalized to [0,1]).
The best-fit quadratic parameters we adopt are:
a = 12.3859 + 0.0102 - 0.0023 (km/s)
b = 0.0321 + 0.0132 - 0.0218 (km/s)
c = -0.0201 + 0.0099 - 0.011 (km/s)
For TOI 5398, we subtracted a constant RV offset of:
-9.561 - 0.045 + 0.013 (km/s).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 27-Nov-2024