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The analysis of whole-sky galaxy surveys commonly suffers from the problems of shot-noise and incomplete sky coverage (e.g. at the Zone of Avoidance). The orthogonal set of spherical harmonics is utilized here to expand the observed galaxy…

Astrophysics · Physics 2009-10-22 O. Lahav , K. B. Fisher , Y. Hoffman , C. A. Scharf , S. Zaroubi

We present the second results of an ensemble and systematic survey of oscillation mode variability in compact pulsators observed with the original {\sl Kepler} mission. Two types of flux calibrations, raw and corrected, collected on two hot…

Solar and Stellar Astrophysics · Physics 2021-11-03 Weikai Zong , Stephane Charpinet , Gerard Vauclair

Spinning neutron stars (NSs) can emit continuous gravitational waves (GWs) that carry a wealth of information about the compact object. If such a signal is detected, it will provide us with new insight into the physical properties of matter…

General Relativity and Quantum Cosmology · Physics 2023-09-12 Wen-Fan Feng , Tan Liu , Jie-Wen Chen , Yan Wang , Soumya D. Mohanty

We propose for the first time that KIC 12602250 is a low-amplitude radial double-mode $\delta$ Scuti star with amplitude modulation. The detailed frequency analysis is given for the light curve of KIC 12602250 which is delivered from the…

Solar and Stellar Astrophysics · Physics 2021-11-10 Chenlong Lv , Ali Esamdin , Xiangyun Zeng , J. Pascual-Granado , Taozhi Yang , Junhui Liu

We perform an exhaustive follow-up analysis of a subsolar-mass (SSM) gravitational wave (GW) candidate reported by Phukon et al. from the second observing run of Advanced LIGO. This candidate has a reported signal-to-noise ratio (SNR) of…

Compact white dwarf (WD) binaries are important sources for space-based gravitational-wave (GW) observatories, and an increasing number of them are being identified by surveys like ZTF. We study the effects of nonlinear dynamical tides in…

Solar and Stellar Astrophysics · Physics 2020-07-08 Hang Yu , Nevin N. Weinberg , Jim Fuller

Gravitational waves emitted by binary neutron stars (BNS) provide information about the internal structure of neutron stars (NSs), helping to verify dense matter equations of state. We investigate how the measurement accuracy of NS's tidal…

General Relativity and Quantum Cosmology · Physics 2026-03-10 Gyeongbin Park , Chang-Hwan Lee , Hee-Suk Cho

Using Chandra data taken on 2008 June, we detected pulsations at 2.59439(4) s in the soft gamma-ray repeater SGR 1627-41. This is the second measurement of the source spin period and allows us to derive for the first time a long-term…

High Energy Astrophysical Phenomena · Physics 2009-11-10 P. Esposito , M. Burgay , A. Possenti , R. Turolla , S. Zane , A. De Luca , A. Tiengo , G. L. Israel , F. Mattana , S. Mereghetti , M. Bailes , P. Romano , D. Götz , N. Rea

A tunable far-infrared laser sideband spectrometer was used to investigate a nitric oxide sample enriched in 18O between 0.99 and 4.75 THz. Regular, electric dipole transitions were recorded between 0.99 and 2.52 THz, while magnetic dipole…

Astrophysics of Galaxies · Physics 2015-04-21 Holger S. P. Müller , Kaori Kobayashi , Kazumasa Takahashi , Kazuko Tomaru , Fusakazu Matsushima

We have conducted a mini-survey for low-frequency radio emission from some of the closest brown dwarfs to the Sun with rapid rotation rates: SIMP J013656.5+093347, WISEPC J150649.97+702736.0, and WISEPA J174124.26+255319.5. We have placed…

The space gravitational wave detector LISA is expected to detect $\sim10^4$ of nearly monochromatic binaries, after $\sim 10$\.yr operation. We propose to measure the inspiral/outspiral binary fluxes in the frequency space, by processing…

High Energy Astrophysical Phenomena · Physics 2022-02-09 Naoki Seto

The analysis of eclipsing binaries containing non-radial pulsators allows: i) to combine two different and independent sources of information on the internal structure and evolutionary status of the components, and ii) to study the effects…

Solar and Stellar Astrophysics · Physics 2015-06-18 C. Maceroni , H. Lehmann , R. da Silva , J. Montalbán , C. -U. Lee , H. Ak , R. Deshpande , K. Yakut , J. Debosscher , Z. Guo , S. -L. Kim , J. W. Lee , J. Southworth

KIC8264293 is a fast rotating B-type pulsator observed by Kepler satellite. Its photometric variability is mainly due to pulsations in high-order g modes. Besides, we detected a weak H$\alpha$ emission. Thus, the second source of…

Solar and Stellar Astrophysics · Physics 2022-02-09 Wojciech Szewczuk , Przemysław Walczak , Jadwiga Daszyńska-Daszkiewicz , Dawid Moździerski

It has long been expected that in some scenarios when a white dwarf (WD) grows to the Chandrasekhar limit, it can undergo an accretion induced collapse (AIC) to form a rapidly rotating neutron star. Nevertheless, the detection of such…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Anthony L. Piro , S. R. Kulkarni

We report on phase-resolved optical spectroscopy and photometry in the R and B bands of the white dwarf candidate ZTF 185139.81+171430.3. The source has been reported to be variable with a large amplitude of close to 1 magnitude, in the R…

Solar and Stellar Astrophysics · Physics 2025-10-09 C. C. Pedersen , M. R. M. Knudsen , K. Valeckas , L. Izzo , T. M. Tauris , J. P. U. Fynbo

Sagittarius A* (Sgr A*) is the variable radio, near-infrared (NIR), and X-ray source associated with accretion onto the Galactic center black hole. We present an analysis of the most comprehensive NIR variability dataset of Sgr A* to date:…

From an examination of ~18,000 Kepler light curves of K- and M-stars we find some 500 which exhibit rotational periods of less than 2 days. Among such stars, approximately 50 show two or more incommensurate periodicities. We discuss the…

Solar and Stellar Astrophysics · Physics 2016-02-05 Katalin Oláh , Saul Rappaport , Matthew Joss

Spike train signals recorded from a large population of neurons often exhibit low-dimensional spatio-temporal structure and modeled as conditional Poisson observations. The low-dimensional signals that capture internal brain states are…

Neurons and Cognition · Quantitative Biology 2024-08-19 Hyungju Jeon , Il Memming Park

Finite-size effects on the gravitational wave signal from a neutron star merger typically manifest at high frequencies where detector sensitivity decreases. Proposed sensitivity improvements can give us access both to stronger signals and…

General Relativity and Quantum Cosmology · Physics 2021-01-04 Carl-Johan Haster , Katerina Chatziioannou , Andreas Bauswein , James Alexander Clark

{KIC~8975515 is a \emph{Kepler} double-lined spectroscopic binary system with hybrid pulsations. Two components have similar atmospheric properties (T$_{\rm eff}$ $\sim$ 7400~K), and one of them is a fast rotator ($v\sin i = 162$ versus 32…

Solar and Stellar Astrophysics · Physics 2020-07-01 A. Samadi-Ghadim , P. Lampens , D. M. Jassur , P. Jofré