Search Publications
Hints of point-symmetric structures in SN 1987A: The jittering jets explosion mechanism
Soker, Noam
I identify a point-symmetric structure composed of three pairs of clumps in the recently released JWST image of the ejecta of SN 1987A and argue that these pairs of clumps support the jittering jets explosion mechanism (JJEM) for SN 1987A. I compare this point-symmetric structure with the multipolar-lobe morphology of a post-asymptotic giant branc…
Unveiling δ Scuti and γ Doradus hybrid pulsation of HD 53166 and HD 53349 plus rich frequencies in HD 52788
Zhou, Ai-Ying
We present discoveries of the hybrid δ Scuti and γ Doradus types stellar pulsational variability of two stars, HD 53166 and HD 53349, which were previously used as comparison in the differential photometry of a known δ Scuti star HD 52788. More surprisingly, HD 52788 exhibits 126 pulsation frequencies in a small domain in 4-12 d-1 based…
Estimating the absolute parameters of W UMa-type binary stars using Gaia DR3 parallax
Poro, Atila; Nourmohammad, Mahshid; Hedayatjoo, Mahya +7 more
The accuracy of absolute parameters' estimation in contact binary systems is important for investigating their evolution and solving some challenges. The Gaia DR3 parallax is one of the methods used for estimating the absolute parameters, in cases where photometric data is the only one that is available. The use of this method includes advantages …
Discovery of four new EL CVn-type binaries in the Gaia eclipsing binaries
Wang, Kun; Ren, Anbing; Peng, Yuhui
In this paper, we performed a search for EL CVn-type binaries based on the Gaia and TESS data. Through the combination of the Gaia DR3 eclipsing binary catalogue and the Gaia DR3 spectroscopic binary catalogue, we have identified 13 stars exhibiting EL CVn-like characteristics. Among these stars, nine have already been identified as EL CVn binarie…
Exploring the cosmological model in f(R ,Tϕ) gravity with observational constraints
Bhardwaj, Vinod Kumar; Garg, Priyanka
We have investigated an isotropic and homogeneous cosmological model of the universe in f(R ,Tϕ) gravity, where Tϕ is the trace of the energy-momentum tensor and R is the Ricci scalar. We developed and presented exact solutions of field equations of the proposed model by taking the parametrization q(z) = α + βz/1 + z , where …
Physical and geometrical properties of an Algol type eclipsing binary with a δ Scuti pulsator: HD 221072
Gürol, B.; Özdemir, S.; Gürsoytrak-Mutlay, S. H. +1 more
In this study, we obtained physical and geometrical parameters of an Algol type eclipsing binary hosting a δ Scuti pulsator. Based on the Transiting Exoplanet Survey Satellite (TESS) observations of HD 221072 system published in Sectors 24, 57, and 58, we obtained the photometric solution of the eclipsing binary. The light curve modelling reveals …
BD UMi: Eccentric detached binary with γ Doradus type component
Gürol, Birol
BD UMi is an Algol-type eccentric eclipsing binary with one of the components showing γ Doradus type pulsation. In this study we used the Transiting Exoplanet Survey Satellite (TESS) observations of the BD UMi system published in total of 16 sectors. We obtained the minima times of the eclipsing system and refined new light elements by using (O - …
Kinematical and ellipsoidal properties of the inner-halo hot subdwarfs observed in Gaia DR3 and LAMOST DR7
Elsanhoury, W. H.
Studying the kinematics of inner-halo hot subdwarfs with Gaia DR3 and LAMOST DR7. Three sets of program stars were considered including subsections namely sdB and sdO. Estimating their inner kinematics and velocity ellipsoid parameters. Determine the average local Galactic rotational constants (i.e., Oort's constants).
Resolving the pulsation contents of 13 δ Scuti stars with TESS and K2
Zhou, Ai-Ying
Using the TESS and Kepler K2 light curve archives, I have reanalyzed 13 known δ Scuti stars. AD Ari is now reclassified as a rotating ellipsoidal binary variable. EX Cnc and HD 73712 are reclassified as hybrid δ Sct-γ Dor pulsators. EX Cnc turns out to be an enticing asteroseismic target because of its three distinct groups of pulsation frequencie…
Photometric study of the overcontact binary NSVS2910034
Tobin, R. Wes; Berrington, Robert C.
We present BVRC+TESS differential photometry of an eclipsing binary system NSVS 2910034. A period analysis reveals unusual variations that are inconsistent with systemic orbital period changes and may be due to surface activity. The best fit models are consistent with a W-type W UMa overcontact binary, consisting of a less massive G7 spectral type…