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Asteroseismology has emerged as a powerful tool to unravel the intricate relationships between evolved stars and their planetary systems. In this study, we leverage this technique to investigate the evolutionary stages of five exoplanet host stars, each exhibiting solar-like oscillations. Building on our previous work that identified two host stars as red clump and red giant branch (RGB) stars, this study focuses on a new and broader sample. By precisely measuring asteroseismic parameters such as the period spacing of dipole gravity modes ($\Delta\Pi_{1}$), we provide definitive confirmation of these stars' evolutionary states as subgiants or RGB stars. These results are not only crucial for understanding the internal structures of evolved stars but also for predicting the eventual fate of their planetary companions, which may face engulfment as their host stars expand. This research highlights the profound role of asteroseismology in advancing our knowledge of planetary system evolution and opens new pathways for exploring how stellar evolution impacts planetary survival. Our findings set the stage for future studies on the dynamic fates of exoplanets, providing key insights into the intricate processes of stellar and planetary evolution.

Eclipsing Algol-type systems containing a $\delta$ Scuti (hereafter $\delta$ Sct) star enable precise determination of physical parameters and the investigation of stellar internal structure and evolution. We present the absolute parameters of CZ Aquarius (hereafter CZ Aqr) based on TESS data. CZ Aqr has an orbital period of 0.86275209 d, a mass ratio of 0.489 (6), and the secondary component nearly fills its Roche lobe. $O-C$ analysis reveals a downward parabolic trend and a cyclical variation with a period of 88.2 yr. The downward parabola suggests a long-term decrease in the orbital period with $\dot{P}$ = -3.09$\times$$10^{-8}$ d $\textrm{yr}^{-1}$. The mass loss rate is estimated to be 4.54$\times$$10^{-9}$ M$_{\odot}$ $\textrm{yr}^{-1}$, which possibly due to magnetic stellar wind or hot spot. The cyclical variation might be caused by the light travel time effect via the presence of a third body with a minimum mass of $M_{3min}$ = 0.312 (21) M$_{\odot}$. Additionally, there are two possible celestial bodies in a 2:7 resonance orbit around CZ Aqr. The asymmetric light curve is explained by adding a hot spot on the surface of the primary star. After removing the binary model, 26 frequencies were extracted from TESS data. Two radial modes were newly identified among three possible independent frequencies. Our results show that the eclipsing Algol-type system is composed of a $\delta$ Sct primary star and a subgiant star in a quadruple system.

The massive semi-detached binary with a long-term decreasing orbital period may involve a rapid mass-transfer phase in Case A, and thus they are good astrophysical laboratories for investigating the evolution of massive binary stars. In this work, by using the long-term observational light curves from the OGLE project and other data in the low-metallicity LMC, four semi-detached massive binaries with long-term decreases in the orbital periods are detected from 165 EB-type close binaries. It is found that the more massive component in S07798 is filling its Roche lobe where the period decrease is caused by mass transfer from the primary to the secondary. However, the other three (S03065, S12631, S16873) are semi-detached binaries with a lobe-filling secondary where the mass transfer between the components should cause the period to increase if the angular momentum is conservative. The long-term period decreases in these three systems may be caused by the angular momentum loss. Additionally, the orbital periods of three systems (S03065, S07798, S16873) are detected to show cyclic variation with periods shorter than 11 years, which can be plausibly explained by the presence of close-in third bodies in these massive binaries. Based on all of these results, it is suggested that the detected four semi-detached binaries almost have multiplicity. The companion stars are crucial for the origin and evolution of these massive close binaries.

Heartbeat stars (HBSs) with tidally excited oscillations (TEOs) are ideal astrophysical laboratories for studying the internal properties of the systems. In this paper, five new HBSs exhibiting TEOs are discovered using TESS photometric data. The orbital parameters are derived using a corrected version of Kumar et al.'s model based on the Markov Chain Monte Carlo (MCMC) method. The TEOs in these objects are examined, and their pulsation phases and modes are identified. The pulsation phases of the TEOs in TIC 266809405, TIC 266894805, and TIC 412881444 are consistent with the dominant $l=2$, $m=0$, or $\pm2$ spherical harmonic. For TIC 11619404, although the TEO phase is close to the $m=+2$ mode, the $m = 0$ mode cannot be excluded because of the low inclination in this system. The TEO phase in TIC 447927324 shows a large deviation ($>2\sigma$) from the adiabatic expectations, suggesting that it is expected to be a traveling wave rather than a standing wave. In addition, these TEOs occur at relatively low orbital harmonics, and we cautiously suggest that this may be an observational bias. These objects are valuable sources for studying the structure and evolution of eccentricity orbit binaries and extending the TESS HBS catalog with TEOs., Comment: 9pages, 5figures

Heartbeat stars (HBSs) are ideal astrophysical laboratories to study the formation and evolution of binary stars in eccentric orbits and the internal structural changes of their components under strong tidal action. We discover 23 new HBSs based on TESS photometric data. The orbital parameters, including orbital period, eccentricity, orbital inclination, argument of periastron, and epoch of periastron passage of these HBSs are derived by using a corrected version of Kumar et al.'s model based on the Markov Chain Monte Carlo (MCMC) method. The preliminary results show that these HBSs have orbital periods in the range from 2.7 to 20 days and eccentricities in the range from 0.08 to 0.70. The eccentricity-period relation of these objects shows a positive correlation between eccentricity and period, and also shows the existence of orbital circularization. The Hertzsprung-Russell diagram shows that the HBSs are not all located in a particular area. The distribution of the derived parameters suggests a selection bias within the TESS survey towards massive HBSs with shorter orbital periods, higher temperatures and luminosities. These objects are a very useful source to study the structure and evolution of eccentricity orbit binaries and to extend the TESS HBS catalog., Comment: 10 pages, 7 figures

Recent progresses in Josephson-junction-based superconducting circuits have propelled quantum information processing forward. However, the lack of a metastable state in most superconducting artificial atoms hinders the development of photonic quantum memory in this platform. Here, we use a single superconducting qubit-resonator system to realize a desired $\Lambda$-type artificial atom, and to demonstrate slow light with a group velocity of 3.6 km/s and the microwave storage with a memory time extending to several hundred nanoseconds via electromagnetically induced transparency. Our results highlight the potential of achieving microwave quantum memory, promising substantial advancements in quantum information processing within superconducting circuits., Comment: 10 pages, 6 figures

We reported a cyclic variation of $O-C$ diagram with a semi-amplitude of 0.0033 days and a period of 1.05 years for the pulsating eclipsing binary HZ Dra. The cyclic variation can be explained by the light travel-time effect via the presence of a close-in third body orbiting around HZ Dra in an elliptical orbit with a maximum semi-major axis of 0.92 au. Based on the W-D code, the contribution of the third light to the total system is determined to be 29 $\%$, which is in agreement with the estimated value. Our light curve modelling indicates an evolving hot and cool spot on the surface of the primary and secondary components, respectively. Their positions are roughly symmetrical to the inner Lagrangian point L1, which could be used to explain the variation in the O$^{'}$Connell effect. Our frequency analysis detects 1 radial p-mode, 7 non-radial p-modes and 1 non-radial g-mode. In addition, a total of 6 multiplets are identified, spaced by the orbital frequency, which can be explained as a tidally split mode caused by the equilibrium tides of the close binary system with a circular orbit. These pulsating features suggest that the primary of HZ Dra is a $\delta$ Scuti star, pulsating in both p- and g-mode and influenced by tidal forces., Comment: 15 pages, 11 figures. The first version is Under Review in ApJ

Asteroseismology offers a profound window into stellar interiors and has emerged as a pivotal technique in exoplanetary research. This study harnesses the Transiting Exoplanet Survey Satellite (TESS) observations to reveal, for the first time, the asteroseismic oscillations of four exoplanet-hosting stars. Through meticulous analysis, we extracted their asteroseismic signatures, enabling the precise determination of stellar masses, radii, luminosities, and surface gravities. These parameters exhibit markedly reduced uncertainties compared to those derived from spectroscopic methods. Crucially, the exoplanets orbiting these stars were initially identified via radial velocity measurements. The refinement of host stellar masses necessitates a corresponding adjustment in planetary characteristics. Employing asteroseismology, we recalibrated the exoplanets' minimum masses and semi-major axes - a novel approach in the field. For instance, the exoplanet HD 5608 b's minimum mass, denoted as Msini, was ascertained to be 1.421 +/- 0.091 M_J through the integration of asteroseismic and radial velocity data. Similarly, two planets within the 7 CMa system yielded Msini values of 1.940 +/- 0.064 MJ and 0.912 +/- 0.067 M_J, respectively. Two planets in HD 33844 system presented Msini figures of 1.726 +/- 0.145 M_J and 1.541 +/- 0.182 M_J, while the HIP 67851 system's planets registered Msini at 1.243 +/- 0.139 M_J and a notably higher 5.387 +/- 0.699 M_J. This investigation extends beyond mere parameter refinement; it underscores the synergy between asteroseismology and exoplanetology, yielding unprecedented precision in system metrics. Focusing on quartet of K-type giants in advanced evolutionary phases, our work positions these systems as invaluable astrophysical laboratories, offering insights into the potential trajectory of our own solar system's fate.

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 of $e$=0.467(3), and a high inclination of $i$=78$^{\circ}$.81(6). The mass ratio $q$=0.981(5), the relative radii (radius divided by semi-major axis) $r_1$=0.0639(2), and $r_2$=0.0715(4) indicate that the secondary component has a less mass and a larger radius, and may have evolved off the main sequence. The eight derived TEO candidates, $n$ = 3, 4, 5, 6, 7, 12, 40, and 44 harmonics, are consistent with or close to the dominant spherical harmonic $l=2$, $m=0$, or $\pm2$, assuming that the spin and orbital axes are aligned, and the pulsations are adiabatic and standing waves. We also identify ten independent frequency candidates, but one of them, $\mathit{f_{7}}$, is more like a modulation of a quasi-periodic signal and the orbits. According to the g-mode frequencies, we find that the rotation period of one component is 11.52(29) days. Although the masses and radii cannot be further constrained due to the lack of sufficient high-precision spectra, the fascinating phenomena in the Fourier spectra are evident and valuable in this system.

V583 Lyr is an extremely low mass ratio Algol-type binary with an orbital period of 11.2580 days. We determined an effective temperature of T_{eff1} = 9000 \pm 350 K from newly observed spectra, which might be an underestimate due to binary mass transfer. The binary mass ratio q = 0.1 \pm 0.004 and the orbital inclination i = 85.5{\deg} are determined based on the assumption that the secondary fills its Roche lobe and rotates synchronously. The radial velocity curve is obtained from time series spectra, allowing for improved estimation of stellar masses and radii: M1 = 3.56 \pm 0.5 Msun, R1 = 2.4 \pm 0.2 Rsun; and M2 = 0.36 \pm 0.02 Msun, R2= 6.9 \pm 0.4 Rsun. The variations in the double-peaked H_{\alpha} emission indicate the formation of a stable disk during mass transfer. V583 Lyr appears to be a post-mass-reversal system, according to the estimated mass transfer using O-C period analysis. Its orbital period is slowly increasing, from which the rate of mass accretion by the primary star is estimated to be dM1/dt = 3.384 \times10^{-8} Msun/yr. The pulsation analysis was conducted on the residuals of the light curve. The primary component was found to be a g-mode pulsating star with 26 frequencies extracted lower than 9 d^{-1}. The frequency groups and rotational splitting properties of the g-mode were studied in detail. This study provides compelling evidence for an accretion disk surrounding the g-mode pulsating primary.

Tidally excited oscillations (TEOs) in Heartbeat Stars (HBSs) are an essential probe of the internal properties of the systems, but their potential has yet to be fully exploited. Based on the orbital parameters of TEO candidates from our previous works, we identify the pulsation phases and amplitudes of TEOs in fourteen Kepler HBSs. Most pulsation phases of most systems can be explained by the dominant being $l=2$, $m=0$, or $\pm2$ spherical harmonic, assuming that the spin and orbital axes are aligned, and the pulsations are adiabatic and standing waves. The largest deviation ($>6\sigma$) occurs in KIC 8459354, which can be explained by the spin-orbit misalignment, and KIC 5877364 has a similar scenario. For KIC 11122789, almost half of the harmonics show large deviations; we cautiously suggest that these harmonics may not be considered TEO candidates. A similar scenario also exists in KIC 6290740. This phases and mode identification approach can also be used inversely to verify the TEO candidates derived by the Fourier analysis. Furthermore, the harmonics with large deviations ($>2\sigma$) in KIC 4377638, KIC 5090937, and KIC 11403032 can be expected to be travelling waves rather than standing waves. In addition, we also suggest that the apsidal motion could cause large deviations in TEO phases from theoretical values., Comment: published on MNRAS

TV Col is a long-period eclipsing intermediate polar (IPs) prototype star for the negative superhump (NSH) system. We investigate the eclipse minima, eclipse depth, and NSH amplitude based on TESS photometry. Using the same analytical method as SDSS J081256.85+191157.8, we find periodic variations of the O-C for eclipse minima and NSH amplitudes with periods of 3.939(25) d and 3.907(30) d, respectively. The periodic variation of the NSH amplitude of TV Col confirms that periodic NSH amplitude changes in response to the tilted disk precession may be universal, which is another evidence that the origin of the NSHs is related to the tilted disk precession. We suggest that the NSH amplitude variation may be similar to the superorbital signal, coming from the periodic change in visual brightness of the energy released by streams touching the tilted disk with tilted disk precession. Finally, we find for the first time that the eclipse depth exhibits bi-periodic variations with periods of P1 = 3.905(11) d and P2 = 1.953(4) d, respectively. P2 is about half of P1 and the disk precession period (P1~ Pprec ~ 2 * P2). We suggest that P1 may come from the periodic change in the brightness of the eclipse center due to tilted disk precession, while P2 may come from two accretion curtains precessing together with the tilted disk, but more verification and discussion are necessary. The discovery of bi-periodic variations in eclipse depth provides a new window for studying IPs and tilted disk precession., Comment: 18 pages, 7 figures, 3 tables; Accepted for publication in The Astrophysical Journal

Negative superhumps (NSHs) are signals a few percent shorter than the orbital period of a binary star and are considered to originate from the reverse precession of the tilted disk. Based on TESS photometry, we find nine new cataclysmic variable stars (CVs) with NSHs. Three (ASAS J1420, TZ Per, and V392 Hya) of these stars similar to AH Her still have NSHs during dwarf nova outbursts, and the NSH amplitude varies with the outburst. The variation in the radius of the accretion disk partially explains this phenomenon. However, it does not explain the rebound of the NSH amplitude after the peak of the outburst and the fact that the NSH amplitude of the quiescence is sometimes not the largest, and it is necessary to combine the disk instability model (DIM) and add other ingredients. Therefore, we suggest that the variation of NSH amplitude with outburst can be an essential basis for studying the origin of NSHs and improving the DIM. The six ( ASASSN-V J1137, ASASSN-V J0611, 2MASS J0715, LAMOST J0925, ASASSN-17qj, and ZTF18acakuxo) remaining stars have been poorly studied, and for the first time we determine their orbital periods, NSHs and Superorbital signal (SOR) periods. The NSH periods and amplitudes of ASASSN-V J1137 and ASASSN-17qj vary with the SOR, and based on the comparison of the observations with the theory, we suggest that a single change in tilted disk angle does not explain the observations of the SOR and that other ingredients need to be considered as well., Comment: 21 pages, 12 figures, accepted for publication in the Astrophysical Journal

Heartbeat stars (HBSs) with tidally excited oscillations (TEOs) are ideal laboratories for studying the effect of equilibrium and dynamical tides. However, studies of TEOs in Kepler HBSs are rare due to the need for better modeling of the equilibrium tide in light curves. We revisit the HBSs in our previous work and study the TEOs in these HBSs based on the derived orbital parameters that could express the equilibrium tide. We also compile a set of analytic procedures to examine the harmonic and anharmonic TEOs in their Fourier spectra. The TEOs of 21 HBSs have been newly analyzed and presented. Twelve of these HBSs show prominent TEOs (signal-to-noise ratio of the harmonics $S/N \ge 10$). The relation between the orbital eccentricities and the harmonic number of the TEOs shows a positive correlation. The relation between the orbital periods and the harmonic number also shows a positive correlation. Furthermore, the distribution of HBSs with TEOs in the Hertzsprung-Russell (H-R) diagram shows that TEOs are more visible in hot stars with surface effective temperatures $T$ $\gtrsim$ 6500 K. These samples may also be valuable targets for future studies of the effect of tidal action in eccentric orbits., Comment: Published on ApJ

Einstein's general theory of relativity not only revolutionized human understanding of the universe, but also brought many gravitational applications in large scale, such as gravitational-wave astronomy, gravitational lensing, and the operation of the global positioning system. However, it still remains a challenge to implement applications for gravitational effects at small spacial extensions on Earth. Here, we investigate a structured waveguide system that allows for the control of an x-ray profile at altitude separations of millimeters and even shorter using the nuclear resonant scattering of x rays. Our present results suggest a potential compact scheme for turning the Earth's gravity into a practical application of x-ray optics., Comment: 6 pages, and 4 figures

Super-orbital signals and negative superhumps are thought to be related to the reverse precession of the nodal line in a tilted disk, but the evidence is lacking. Our results provide new evidence for the precession of the tilted disk. Based on the TESS and K2 photometry, we investigate the super-orbital signals, negative superhumps, positive superhumps, and eclipse characteristics of the long-period eclipsing cataclysmic variable star SDSS J0812. We find super-orbital signals, negative superhumps, and positive superhumps with periods of 3.0451(5) d, 0.152047(2) d, and 0.174686(7) d, respectively, in the K2 photometry, but all disappear in the TESS photometry, where the positive superhumps are present only in the first half of the same campaign, confirming that none of them is permanently present in SDSS J0812. In addition, we find for the first time a cyclic variation of the O-C of minima, eclipse depth, and negative superhumps amplitudes for 3.045(8) d, 3.040(6) d, and 3.053(8) d in SDSS J0812, respectively, and all reach the maximum at ~ 0.75 precession phases of the tilted disk, which provides new evidence for the precession of the tilted disk. We suggest that the O-C and eclipse depth variations may come from a shift of the brightness center of the precession tilted disk. Our first finding on the periodic variation of negative superhumps amplitude with the super-orbital signals is significant evidence that the origin of negative superhumps is related to the precession of the tilted disk., Comment: 21 pages, 16 figures, published in MNRAS

HS 2325+8205 is a long-period eclipsing dwarf nova with an orbital period above the period gap (Porb>3 h) and is reported to be a Z Cam-type dwarf nova. Based on the photometry of the Transiting Exoplanet Survey Satellite (TESS), the light variation and the quasi-periodic oscillation (QPOs) of HS 2325+8205 are studied. Using Continuous Wavelet Transform (CWT), Lomb-Scargle Periodogram (LSP), and sine fitting methods, we find for the first time that there is a QPOs of ~ 2160s in the long outburst top light curves of HS 2325+8205. Moreover, we find that the oscillation intensity of the QPOs of HS 2325+8205 is related to the orbital phase, and the intensity in orbital phases 0.5-0.9 are stronger than in orbital phases 0.1-0.5. Therefore, the relationship between the oscillation intensity of QPOs and the orbital phase may become a research window for the origin of QPOs. In addition, we use the LSP to correct the orbital period of HS 2325+8205 as 0.19433475(6) d.

We experimentally observed an accumulative type of nonlinear attenuation and distortion of slow light, i.e., Rydberg polaritons, with the Rydberg state $|32D_{5/2}\rangle$ in the weak-interaction regime. The present effect of attenuation and distortion cannot be explained by considering only the dipole-dipole interaction (DDI) between Rydberg atoms in $|32D_{5/2}\rangle$. Our observation can be attributed to the atoms in the dark Rydberg states other than those in the bright Rydberg state, i.e., $|32D_{5/2}\rangle$, driven by the coupling field. The dark Rydberg states are all the possible states, in which the population decaying from $|32D_{5/2}\rangle$ accumulated over time, and they were not driven by the coupling field. Consequently, the DDI between the dark and bright Rydberg atoms increased the decoherence rate of the Rydberg polaritons. We performed three different experiments to verify the above hypothesis, to confirm the existence of the dark Rydberg states, and to measure the decay rate from the bright to dark Rydberg states. In the theoretical model, we included the decay process from the bright to dark Rydberg states and the DDI effect induced by both the bright and dark Rydberg atoms. All the experimental data of slow light taken at various probe Rabi frequencies were in good agreement with the theoretical predictions based on the model. This study pointed out an additional decoherence rate in the Rydberg-EIT effect, and provides a better understanding of the Rydberg-polariton system.