Abstract Negative superhumps (NSHs) are signals a few percent shorter than the orbital period of binary star and considered to originate from reverse precession tilted disk. Based on TESS photometry, we find nine new cataclysmic variable stars with NSHs. Three (ASAS J1420, TZ Per, V392 Hya) these similar AH Her still have NSHs during dwarf nova outbursts, NSH amplitude varies outburst. The variation in radius accretion disk partially explains this phenomenon. However, it does not explain...

Abstract TV Col is a long-period eclipsing intermediate polar (IP) prototype star for the negative superhump (NSH) system. We investigate eclipse minima, depth, and NSH amplitude based on TESS photometry. Using same analytical method as SDSS J081256.85+191157.8, we find periodic variations of O − C minima amplitudes with periods 3.939(25) days 3.907(30) days, respectively. The variation confirms that changes in response to tilted disk precession may be universal, which further evidence...

Abstract The merger of compact binary stars produces short gamma-ray bursts (sGRBs), involving channels such as neutron star–neutron star (BNS) and star–black hole (NS–BH). association between sGRB 170817A gravitational wave GW170817 provides reliable evidence for the BNS channel. Some speculations suggest that sGRBs with extended emission (EE) may represent another distinct population. offset is distance GRB sky localization host galaxy center. We compared distributions these two types...

Abstract LT Eri is a long-period eclipsing cataclysmic variable star (CV). This study investigates its outbursts, negative superhumps (NSHs), tilted-disk precession, eclipse-depth variations, and observed minus calculated ( O – C ) behavior, using photometric data from the Transiting Exoplanet Survey Satellite (TESS), Zwicky Transient Facility, All-Sky Automated for Supernovae, American Association of Variable Star Observers. Our analysis reveals an outburst period 14.7(31) days, with...

Abstract Dwarf novae (DNe) are semidetached binaries, where a white dwarf accretes material from cool main-sequence companion via an accretion disk, and known for their intermittent outbursts, making them key systems studying physics. The accumulation of large survey data sets has challenged traditional models, which assumed that the disk remains hot cannot produce superoutbursts during standstill Z Camelopardalis (Z Cam)-type DN require mass ratio q = M 2 / 1 ≤ 0.25–0.33. Here we report...

Super-orbital signals and negative superhumps are thought to be related the reverse precession of nodal line in a tilted disk, but evidence is lacking. Our results provide new for disk. Based on TESS K2 photometry, we investigate super-orbital signals, superhumps, positive eclipse characteristics long-period eclipsing cataclysmic variable star SDSS J0812. We find with periods 3.0451(5) d, 0.152047(2) 0.174686(7) respectively, all disappear where present only first half same campaign,...

Abstract AH Her is a Z Cam-type dwarf nova with an orbital period of ∼0.258 days. Dwarf oscillations and long-period have been detected, but no quasiperiodic (QPOs) negative superhumps (NSHs) found. We investigated the association between NSHs, QPOs, outbursts based on Transiting Exoplanet Survey Satellite photometry. find for first time NSHs 0.24497(1) days in Her, trace variation amplitude outburst. The most significant at quiescence, weakening as outburst rises, becoming undetectable top,...

Abstract Heartbeat stars (HBSs) with tidally excited oscillations (TEOs) are ideal laboratories for studying the effect of equilibrium and dynamical tides. However, studies TEOs in Kepler HBSs rare due to need better modeling tide light curves. We revisit our previous work study these based on derived orbital parameters that could express tide. also compile a set analytic procedures examine harmonic anharmonic their Fourier spectra. The 21 have been newly analyzed presented. Twelve show...

Abstract Tilted disk precession exists in different objects. Negative superhumps (NSHs) cataclysmic variable stars are believed to arise from the interaction between reverse of a tilted and streams secondary star. Utilizing Transiting Exoplanet Survey Satellite photometry, we present comprehensive investigation into NSHs dwarf nova (DN) HS 2325+8205, employing eclipse minima, depths, NSH frequencies, amplitudes correlation them as windows. We identified with period 0.185671(17) day...

Abstract The IW And-type phenomenon in cataclysmic variables presents a significant challenge to the accretion disk instability model. Using photometric data from All-Sky Automated Survey for Supernovae, Zwicky Transient Facility, and Transiting Exoplanet Satellite, we identify Karachurin 12 as new noneclipsing object with cycle period of 35.69(3) days. We also report first time that is negative superhump (NSH) system featuring precessing tilted disks, precession, orbital, NSH periods...

Abstract Heartbeat stars (HBSs) are astrophysical laboratories for studying binaries with eccentric orbits. A catalog of 173 Kepler HBSs was reported by Kirk et al., and we have modeled 153 them using a corrected version Kumar al.'s model based on the Markov Chain Monte Carlo method. The orbital parameters, including period, eccentricity, inclination, argument periastron, epoch periastron passage these HBSs, been determined presented. Orbital parameters more than 100 systems obtained first...

HS 2325+8205 is a long-period eclipsing dwarf nova with an orbital period above the gap (Porb>3 h) and reported to be Z Cam-type nova. Based on photometry of Transiting Exoplanet Survey Satellite (TESS), light variation quasi-periodic oscillation (QPOs) are studied. Using Continuous Wavelet Transform (CWT), Lomb-Scargle Periodogram (LSP), sine fitting methods, we find for first time that there QPOs ~ 2160s in long outburst top curves 2325+8205. Moreover, intensity related phase, phases...

ABSTRACT Tidally excited oscillations (TEOs) in Heartbeat Stars (HBSs) are an essential probe of the internal properties systems, but their potential has yet to be fully exploited. Based on orbital parameters TEO candidates from our previous works, we identify pulsation phases and amplitudes TEOs 14 Kepler HBSs. Most most systems can explained by dominant being l = 2, m 0, or ±2 spherical harmonic, assuming that spin axes aligned, pulsations adiabatic standing waves. The largest deviation...

Abstract Massive contact binaries refer to the close binary systems in which components have filled their respective Roche lobes and share a common envelope with early-type spectra. Twin are special type of system characterized by two nearly equal masses. The Magellanic Cloud, comprising Large Cloud (LMC) Small is fascinating galaxy that distinct from Milky Way. With its low metallicity, it serves as an ideal test bed for studying formation evolution massive testing theoretical models. In...

ABSTRACT Gamma-ray bursts (GRBs) are the most intense explosions in Universe. GRBs with extended emission (GRBs EE) constitute a small subclass of GRBs. EE divided into EE-I and EE-II GRBs, according to Amati empirical relationship rather than duration. We test here if these two types GRB have different origins based on their luminosity function (and formation rate). Therefore, we use Lynden-Bell’s c− method investigate rate without any assumption. calculate For fitting can be written as...

TV Col is a long-period eclipsing intermediate polar (IPs) prototype star for the negative superhump (NSH) system. We investigate eclipse minima, depth, and NSH amplitude based on TESS photometry. Using same analytical method as SDSS J081256.85+191157.8, we find periodic variations of O-C minima amplitudes with periods 3.939(25) d 3.907(30) d, respectively. The variation confirms that changes in response to tilted disk precession may be universal, which another evidence origin NSHs related...

Tidally excited oscillations (TEOs) in Heartbeat Stars (HBSs) are an essential probe of the internal properties systems, but their potential has yet to be fully exploited. Based on orbital parameters TEO candidates from our previous works, we identify pulsation phases and amplitudes TEOs fourteen Kepler HBSs. Most most systems can explained by dominant being $l=2$, $m=0$, or $\pm2$ spherical harmonic, assuming that spin axes aligned, pulsations adiabatic standing waves. The largest deviation...

We present the eclipsing Heartbeat Star KIC 9704906 with tidally excited oscillations (TEOs) and gamma Doradus/delta Scuti hybrid pulsations. The derived parameters show that it has an orbital period of $P$=8.7529108(1) days, a high eccentricity $e$=0.467(3), inclination $i$=78$^{\circ}$.81(6). mass ratio $q$=0.981(5), relative radii (radius divided by semi-major axis) $r_1$=0.0639(2), $r_2$=0.0715(4) indicate secondary component less larger radius, may have evolved off main sequence. eight...

We reported a cyclic variation of $O-C$ diagram with semi-amplitude 0.0033 days and period 1.05 years for the pulsating eclipsing binary HZ Dra. The can be explained by light travel-time effect via presence close-in third body orbiting around Dra in an elliptical orbit maximum semi-major axis 0.92 au. Based on W-D code, contribution to total system is determined 29 $\%$, which agreement estimated value. Our curve modelling indicates evolving hot cool spot surface primary secondary...

The merger of compact binary stars produces short gamma-ray bursts (sGRBs), involving channels such as neutron star - (BNS) and black hole (NS-BH). association between sGRB 170817A gravitational wave GW 170817 provides reliable evidence for the BNS channel. spatial distribution rate differ mergers NS-BH mergers. Some speculations suggest that sGRBs with extended emission (EE) may represent another distinct population. We compared offset distributions these two types samples found they follow...

Tilted disk precession exists in different objects. Negative superhumps (NSHs) cataclysmic variable stars (CVs) are hypothesized to arise from the interaction between reverse of a tilted and streams secondary star. Utilizing TESS photometry, we present comprehensive investigation into NSHs dwarf nova (DN) HS 2325+8205, employing eclipse minima, depths, NSH frequencies, amplitudes correlation them as windows. We report discovery 2325+8205 with period 0.185671(17) d. The frequency was found...

Abstract KV Vel is a noneclipsing short-period ( P = 0.3571 days) close binary containing very hot subdwarf primary (77,000 K) and cool low-mass secondary star (3400 that located at the center of planetary nebula DS 1. The changes in orbital period were analyzed based on 262 new times light maximum together with those compiled from literature. It discovered O − C curve shows small-amplitude (0.ͩ0034) cyclic variation 29.55 yr. explanation by solar-type magnetic activity cycles component...