44 citations · 451 across the 40 of their papers we have counts for
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Unveiling the properties of pulsating low-mass helium-core white dwarfs through TESS asteroseismology I. First results
Leila M. Calcaferro, Nikoo Hosseininezhad, Murat Uzundag +4
Recent space-based photometry, particularly from TESS, has opened new possibilities for probing the internal structure of low-mass (LM) helium (He)-core white dwarfs (WDs). We pres…
Asteroseismology of the ZZ Ceti star WD 1310+583 using the Transiting Exoplanet Survey Satellite
Zs. Bognár, M. Uzundag, F. C. De Gerónimo +4
Aims. By analysing the light curves of the ZZ Ceti star WD 1310+583, we aim to determine its pulsational frequencies and to give constraints on the main stellar parameters using th…
A 500 pc volume-limited sample of hot subluminous stars II. Atmospheric parameters, mass distribution, and kinematics
H. Dawson, M. Dorsch, S. Geier +30
We present a quantitative spectroscopic and kinematic analysis of a volume-complete sample of hot subluminous stars within 500 pc of the Sun, assembled using accurate parallax meas…
Multiperiodic pulsations of the unique DAQ white dwarf J0551+4135: insights into a merger remnant
Murat Uzundag, Mukremin Kilic, Francisco C. De Gerónimo +7
2MASS J05513444+4135297 (herafter J0551+4135) is the only pulsating DAQ white dwarf known with a carbon and hydrogen atmosphere. Its unusual atmospheric composition and kinematics…
Observing bright pulsating white dwarfs with PLATO: A new window into the late stages of stellar evolution
Murat Uzundag, Alejandro H. Corsico, Nicholas Jannsen +17
We present the scientific case for exploiting the capabilities of the PLATO mission to study bright pulsating white dwarfs across a wide spectral range, including hydrogen-deficien…
The ZZ Ceti Instability Strip for The Most Massive White Dwarf Pulsators
Gracyn Jewett, Mukremin Kilic, Adam Moss +10
We present time-series photometry of 31 massive DA white dwarfs with within the ZZ Ceti instability strip from the Montreal White Dwarf Database 100 pc sampl…
Asteroseismology of WD J004917.14-252556.81, the Most Massive Pulsating White Dwarf
O. Caliskan, M. Uzundag, M. Kilic +10
We present extensive follow-up time-series photometry of WD J00492525, the most massive pulsating white dwarf currently known with and $\log{\i…
Discerning internal conditions of pulsating hot subdwarf B stars. Modelling multiple trapped modes in KIC 10001893
Hamed Ghasemi, Murat Uzundag, Cole Johnston +1
The frequencies of gravity mode oscillations are determined by the chemical, thermal, and structural properties of stellar interiors, facilitating the study of internal mixing mech…
Volume-limited sample of low-mass red giant stars, the progenitors of hot subdwarf stars II. Sample validation
Diego Benitez-Palacios, Murat Uzundag, Maja Vučković +6
We investigate the progenitors of long-period hot subdwarf B (sdB) binaries, which form when low-mass red giant branch (RGB) stars lose their envelopes through stable Roche lobe ov…
Discovery of the richest pulsating ultra-massive white dwarf
Francisco C. De Geronimo, Murat Uzundag, Alberto Rebassa-Mansergas +5
The discovery of pulsations in ultra-massive white dwarfs can help to probe their interiors and unveil their core composition and crystallized mass fraction through asteroseismic t…
An analysis of spectroscopic, seismological, astrometric, and photometric masses of pulsating white dwarf stars
Leila M. Calcaferro, Alejandro H. Córsico, Murat Uzundag +3
A central challenge in the field of stellar astrophysics lies in accurately determining the mass of isolated stars. However, for pulsating white dwarf (WD) stars, the task becomes…
A 500 pc volume-limited sample of hot subluminous stars I. Space density, scale height, and population properties
H. Dawson, S. Geier, U. Heber +25
We present the first volume-limited sample of spectroscopically confirmed hot subluminous stars out to 500 pc, defined using the accurate parallax measurements from the {\em Gaia}…
Pulsating hydrogen-deficient white dwarfs and pre-white dwarfs observed with TESS VI. Asteroseismology of the GW Vir-type central star of the Planetary Nebula NGC 246
Leila M. Calcaferro, Paulina Sowicka, Murat Uzundag +7
Significant advances have been achieved through the latest improvements in the photometric observations accomplished by the recent space missions, substantially boosting the study…
A comprehensive search for hot subdwarf stars using Gaia and TESS I. Pulsating hot subdwarf B stars
Murat Uzundag, Jurek Krzesinski, Ingrid Pelisoli +4
Hot subdwarf B (sdB) stars are evolved, subluminous, helium-burning stars, most likely formed when red-giant stars lose their hydrogen envelope via interactions with close companio…
Asteroseismological analysis of the polluted ZZ Ceti star G29-38 with TESS
Murat Uzundag, Francisco C. De Gerónimo, Alejandro H. Córsico +15
G\,2938 (TIC~422526868) is one of the brightest () and closest (\,pc) pulsating white dwarfs with a hydrogen-rich atmosphere (DAV/ZZ Ceti class). It was obser…
The bright blue side of the night sky: Spectroscopic survey of bright and hot (pre-) white dwarfs
Nicole Reindl, Ramazan Islami, Klaus Werner +10
We report on the spectroscopic confirmation of 68 new bright ( mag) and blue (pre-)white dwarfs (WDs). This finding has allowed us to almost double the number of the h…
Asteroseismology of hot subdwarf B stars observed with TESS: discovery of two new gravity mode pulsating stars
Murat Uzundag, Roberto Silvotti, Andrzej S. Baran +4
TIC033834484 and TIC309658435 are long-period pulsating subdwarf B star, which were observed extensively (675 and 621 days, respectively) by the Transiting Exoplanet Survey Satelli…
Asteroseismology of PG 1541651 and BPM 31594 with TESS
Alejandra D. Romero, Gabriela Oliveira da Rosa, S. O. Kepler +5
We present the photometric data from TESS for two known ZZ Ceti stars, PG 1541+651 and BPM 31594. Before TESS, both objects only had observations from short runs from ground-based…
Pulsating H-deficient WDs and pre-WDs observed with TESS: V. Discovery of two new DBV pulsators, WD J152738.4-450207.4 and WD 1708-871, and asteroseismology of the already known DBV stars PG 1351+489, EC 20058-5234, and EC 04207-4748
Alejandro H. Córsico, Murat Uzundag, S. O. Kepler +9
The {\sl TESS} space mission has recently demonstrated its great potential to discover new pulsating white dwarf and pre-white dwarf stars, and to detect periodicities with high pr…
Volume-limited sample of low-mass red giant stars, the progenitors of hot subdwarf stars I. Sample selection and binary classification method
Murat Uzundag, Matias I. Jones, Maja Vučković +3
The current theory predicts that hot subdwarf binaries are produced from evolved low-mass binaries that have undergone mass transfer and drastic mass loss during either a common en…
Kepler and TESS Observations of PG 1159-035
Gabriela Oliveira da Rosa, S. O. Kepler, Alejandro H. Córsico +11
PG 1159-035 is the prototype of the DOV hot pre-white dwarf pulsators. It was observed during the Kepler satellite K2 mission for 69 days in 59 s cadence mode and by the TESS satel…
Pulsating hydrogen-deficient white dwarfs and pre-white dwarfs observed with TESS -- IV. Discovery of two new GW Vir stars: TIC0403800675 and TIC1989122424
Murat Uzundag, Alejandro H. Corsico, S. O. Kepler +4
We present two new GW Vir-type pulsating white dwarf stars, TIC\,0403800675 (WD\,J115727.68-280349.64) and TIC\,1989122424 (WD J211738.38-552801.18) discovered in the Transiting Ex…
Discovery of 74 new bright ZZ Ceti stars in the first three years of TESS
A. D. Romero, S. O. Kepler, J. J. Hermes +17
We report the discovery of 74 new pulsating DA white dwarf stars, or ZZ Cetis, from the data obtained by the Transiting Exoplanet Survey Satellite (TESS) mission, from Sectors 1 to…
Pulsating hydrogen-deficient white dwarfs and pre-white dwarfs observed with {\it TESS}: III. Asteroseismology of the DBV star GD 358
Alejandro H. Córsico, Murat Uzundag, S. O. Kepler +14
The collection of high-quality photometric data by space telescopes is revolutionizing the area of white-dwarf asteroseismology. Among the different kinds of pulsating white dwarfs…