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Revisiting the δ Scuti star FG Virginis using Kepler K2 and TESS data

Journal Article · · Frontiers in Astronomy and Space Sciences
 [1];  [2];  [3]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. New Mexico State Univ., Las Cruces, NM (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); New Mexico State Univ., Las Cruces, NM (United States)
FG Virginis is a δ Scuti variable star that was the target of several ground-based multisite photometric campaigns from 1992 to 2004. Over 75 pulsation frequencies were detected (Breger et al., Astron. Astrophys., 2005, 435, 955–965), more than for any other δ Sct star before the era of space photometry. FG Vir was observed for 52 days in 30-minute cadence photometry by the NASA Kepler spacecraft K2 mission in 2016, and for 23 days in 2-minute cadence photometry by the NASA TESS spacecraft in 2021. We present light curves and amplitude spectra obtained from these space missions. We find around 30 significant frequencies in the K2 data, and more than 100 significant frequencies in the TESS data. There is good correspondence between the first 10 or so highest-amplitude modes found in the K2 and TESS data and those found from the ground-based multisite campaigns, although the amplitude order is slightly different, indicating some stability in mode frequencies and amplitudes spanning 20 years. However, the 9th highest-amplitude mode of Breger et al. has moved down considerably in amplitude rank, while the 35th highest-amplitude mode has moved up to near the top ten as seen in both the K2 and TESS data. We find several low frequencies between 0.3 and 3 cycles per day in the TESS data that were not detected using the ground-based data. If low-frequency pulsations are confirmed, FG Vir would be classified as a δ Sct/γ Dor hybrid variable star. We also review stellar model results and some of the challenges for asteroseismology for this well-studied δ Sct star.
Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
89233218CNA000001
OSTI ID:
1923639
Report Number(s):
LA-UR-22-26398
Journal Information:
Frontiers in Astronomy and Space Sciences, Journal Name: Frontiers in Astronomy and Space Sciences Vol. 9; ISSN 2296-987X
Publisher:
Frontiers Research FoundationCopyright Statement
Country of Publication:
United States
Language:
English

References (56)

The puzzle of combination frequencies found in heat-driven pulsators journal December 2012
Asteroseismology book January 2010
Hipparcos, the New Reduction of the Raw Data book January 2007
Asteroseismology and interferometry journal November 2007
A new oscillating model suggestion for FG Vir journal February 2005
Pulsation Theory and Stellar Structure journal January 1993
Mode Selection and Other Nonlinear Phenomena in Stellar Oscillations journal January 1993
Very regular high-frequency pulsation modes in young intermediate-mass stars journal May 2020
Efficient synthesis of cyclic amidine-based fluorophoresvia6π-electrocyclic ring closure journal January 2020
HD 50844: a new look at δ Scuti stars from CoRoT space photometry   journal June 2009
The Kepler characterization of the variability among A- and F-type stars : I. General overview journal October 2011
Measuring mean densities of δ Scuti stars with asteroseismology : Theoretical properties of large separations using TOUCAN⋆ journal February 2014
The Gaia mission journal November 2016
Stellar and substellar companions of nearby stars from Gaia DR2 : Binarity from proper motion anomaly⋆ journal March 2019
Gaia Early Data Release 3: Summary of the contents and survey properties (Corrigendum) journal June 2021
The chemical make-up of the Sun: A 2020 vision journal September 2021
Towards a systematic treatment of observational uncertainties in forward asteroseismic modelling of gravity-mode pulsators journal December 2021
Line profile variations in the δ Scuti star FG Virginis: A high number of axisymmetric modes journal December 2002
The δ Scuti star FG Vir. V. The 2002 photometric multisite campaign journal May 2004
Detection of 75+ pulsation frequencies in the δ Scuti star FG Virginis journal May 2005
Inferences from pulsational amplitudes and phases for multimodeδSct star FG Vir journal July 2005
A new method for the spectroscopic identification of stellar non-radial pulsation modes journal July 2006
Rotational and tidal perturbations of nonradial oscillations in a polytropic star journal February 1981
Visual multiples. VII - MK classifications journal March 1981
The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog journal December 2001
Asteroseismology of δ Scuti Stars: A Parameter Study and Application to Seismology of FG Virginis journal December 2001
Kepler Asteroseismology Program: Introduction and First Results
  • Gilliland, Ronald L.; Brown, Timothy M.; Christensen-Dalsgaard, Jørgen
  • Publications of the Astronomical Society of the Pacific, Vol. 122, Issue 888 https://doi.org/10.1086/650399
journal February 2010
The K2 Mission: Characterization and Early Results
  • Howell, Steve B.; Sobeck, Charlie; Haas, Michael
  • Publications of the Astronomical Society of the Pacific, Vol. 126, Issue 938 https://doi.org/10.1086/676406
journal April 2014
HYBRID γ DORADUS-δ SCUTI PULSATORS: NEW INSIGHTS INTO THE PHYSICS OF THE OSCILLATIONS FROM KEPLER OBSERVATIONS journal March 2010
KEPLER MISSION DESIGN, REALIZED PHOTOMETRIC PERFORMANCE, AND EARLY SCIENCE journal March 2010
KIC 5950759: a high-amplitude δ Sct star with amplitude and frequency modulation near the terminal age main sequence journal April 2021
Mode identification and seismic study of δ Scuti, the prototype of a class of pulsating stars journal May 2021
A precise asteroseismic age and metallicity for HD 139614: a pre-main-sequence star with a protoplanetary disc in Upper Centaurus–Lupus journal January 2021
Five young δ Scuti stars in the Pleiades seen with Kepler/K2 journal January 2022
Asteroseismology of the double-radial mode δ Scuti star BP Pegasi journal March 2022
Super-Nyquist asteroseismology with the Kepler Space Telescope journal February 2013
Low frequencies in Kepler δ Scuti stars journal November 2013
Validation of the frequency modulation technique applied to the pulsating δ Sct–γ Dor eclipsing binary star KIC 8569819 journal November 2014
Pulsation frequency distribution in δ Scuti stars journal July 2015
Amplitude modulation in δ Sct stars: statistics from an ensemble study of Kepler targets journal May 2016
Catalogue and properties of δ Scuti stars in binaries journal October 2016
Characterizing the observational properties of δ Sct stars in the era of space photometry from the Kepler mission journal February 2018
The first view of δ Scuti and γ Doradus stars with the TESS mission journal October 2019
Amplitude variability or close frequencies in pulsating stars -- the   Scuti star FG Vir journal May 2006
Matching the frequency spectrum of pre-main sequence stars by means of standard and rotating models journal September 2008
Towards mode selection in δ Scuti stars: regularities in observed and theoretical frequency spectra journal June 2009
Transiting Exoplanet Survey Satellite journal October 2014
Kepler Planet-Detection Mission: Introduction and First Results journal January 2010
Properties of 249 δ Scuti Variable Star Candidates Observed During the NASA K2 Mission journal May 2019
The Pre-main Sequence: Challenges and Prospects for Asteroseismology journal June 2022
UNEXPECTED SERIES OF REGULAR FREQUENCY SPACING OF δ SCUTI STARS IN THE NON-ASYMPTOTIC REGIME. I. THE METHODOLOGY journal May 2016
THE K2 ECLIPTIC PLANE INPUT CATALOG (EPIC) AND STELLAR CLASSIFICATIONS OF 138,600 TARGETS IN CAMPAIGNS 1–8 journal May 2016
UNEXPECTED SERIES OF REGULAR FREQUENCY SPACING OF δ SCUTI STARS IN THE NON-ASYMPTOTIC REGIME. II. SAMPLE–ECHELLE DIAGRAMS AND ROTATION journal June 2016
The Revised TESS Input Catalog and Candidate Target List journal September 2019
Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation journal July 2019
A Detection Threshold in the Amplitude Spectra Calculated from TESS Time-Series Data text January 2021

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