English
Related papers

Related papers: Interstellar Interferometry: Precise Curvature Mea…

200 papers

Pulsar dispersion measures (DMs) have been used to model the electron density of the interstellar medium (ISM) in the Galactic disk as a plane-parallel medium, despite significant scatter in the DM-distance distribution and strong evidence…

Astrophysics of Galaxies · Physics 2020-07-10 Stella Koch Ocker , James M. Cordes , Shami Chatterjee

It is believed that some numerical technique must be employed for the determination of the system parameters of a visual binary or a star with a planet because the relevant equations are not only highly nonlinear but also transcendental…

Astrophysics · Physics 2015-06-24 Hideki Asada , Toshio Akasaka , Masumi Kasai

We present an investigation of spin-orbit angles for planetary system candidates reported by Kepler. By combining the rotational period $P_s$ inferred from the flux variation due to starspots and the projected rotational velocity $V\sin…

Earth and Planetary Astrophysics · Physics 2015-06-05 Teruyuki Hirano , Roberto Sanchis-Ojeda , Yoichi Takeda , Norio Narita , Joshua N. Winn , Atsushi Taruya , Yasushi Suto

Inverse Compton scattering (ICS) is a unique mechanism for producing fast pulses - picosecond and below - of bright X- to gamma-rays. These nominally narrow spectral bandwidth electromagnetic radiation pulses are efficiently produced in the…

Light-pulse atom interferometers rely on the wave nature of matter and its manipulation with coherent laser pulses. They are used for precise gravimetry and inertial sensing as well as for accurate measurements of fundamental constants.…

Quantum Physics · Physics 2015-12-02 Stephan Kleinert , Endre Kajari , Albert Roura , Wolfgang P. Schleich

The study of the younger, and brighter, pulsars is important to understand the optical emission properties of isolated neutron stars. PSRB0540-69, the second brightest (V~22) optical pulsar, is obviously a very interesting target for these…

Solar and Stellar Astrophysics · Physics 2015-05-18 R. P. Mignani , A. Sartori , A. De Luca , B. Rudack , A. Slowikowska , G. Kanbach , P. A. Caraveo

Context. Circumstellar disks and self-luminous giant exoplanets or companion brown dwarfs can be characterized through direct-imaging polarimetry at near-infrared wavelengths. SPHERE/IRDIS at the Very Large Telescope has the capabilities to…

Accurate measurement of pulsar distances via astrometry using very long baseline interferometry enables the improvement of Galactic electron density distribution models, improving distance estimates for the vast majority of pulsars for…

Solar and Stellar Astrophysics · Physics 2011-02-11 A. T. Deller , S. J. Tingay , M. Bailes , J. E. Reynolds

We propose a new procedure for measuring the spin of a black hole with an unprecedented accuracy based on the gravitational lensing of millisecond pulsars. We derive the basic equations for lensing by a rotating black hole. We show that the…

General Relativity and Quantum Cosmology · Physics 2025-08-28 Amjad Ashoorioon , Mohammad Bagher Jahani Poshteh , Robert B. Mann

Due to the inhomogeneity of electron number density, radio waves emitted by pulsars undergo scattering as they pass through the interstellar medium (ISM). However, a connection between large-scale pulsar scattering data and the structure of…

Astrophysics of Galaxies · Physics 2025-02-14 Qiuyi He , Xun Shi , Guangxing Li

A large number of new "black widow" and "redback" energetic millisecond pulsars with irradiated stellar companions have been discovered through radio and optical searches of unidentified \textit{Fermi} sources. Synchrotron emission, from…

High Energy Astrophysical Phenomena · Physics 2016-02-23 Zorawar Wadiasingh , Alice K. Harding , Christo Venter , Markus Boettcher

A theoretical framework for emission originating from rapidly rotating oblate compact objects is described in detail. By using a Hamilton-Jacobi formalism, we show how the special relativistic rotational effects such as aberration of…

High Energy Astrophysical Phenomena · Physics 2018-07-18 Joonas Nättilä , Pauli Pihajoki

Low-frequency spectral studies of radio pulsars represent a key method for uncovering their emission mechanisms, magnetospheric structure, and signal interactions with the surrounding interstellar medium (ISM). In recent years, more…

Astrophysics of Galaxies · Physics 2025-10-13 Ting Yu , Zhongli Zhang , Hongyu Gong , Zhigang Wen

The Large Area Telescope aboard the Fermi spacecraft has detected more than 200 $\gamma$-ray pulsars since its launch in 2008. By concurrently fitting standard geometric model light curves onto Fermi and radio data, researchers have…

High Energy Astrophysical Phenomena · Physics 2018-08-30 M. C. Bezuidenhout , C. Venter , A. S. Seyffert , A. K. Harding

Propagation effects in the interstellar medium and intrinsic profile changes can cause variability in the timing of pulsars, which limits the accuracy of fundamental science done via pulsar timing. One of the best timing pulsars, PSR…

High Energy Astrophysical Phenomena · Physics 2021-10-07 Fang Xi Lin , Hsiu-Hsien Lin , Jing Luo , Robert Main , James McKee , Ue-Li Pen , Dana Simard , Marten H. van Kerkwijk

We use cyclic spectroscopy to directly measure the scintillation parameter $C_1$ for the millisecond pulsar B1937+21. This marks the first time this constant has been measured for any pulsar without assuming a pulse broadening function…

High Energy Astrophysical Phenomena · Physics 2026-05-27 Jacob E. Turner

Optical interferometry provides us with a unique opportunity to improve our understanding of stellar structure and evolution. Through direct observation of rotationally distorted photospheres at sub-milliarcsecond scales, we are now able to…

Solar and Stellar Astrophysics · Physics 2012-04-13 Gerard T. van Belle

Spectra of composite systems (e.g., spectroscopic binaries) contain spatial information that can be retrieved by measuring the radial velocities (i.e., Doppler shifts) of the components in four observations with the slit rotated by 90…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 L. Pasquini , C. Cortés , M. Lombardi , L. Monaco , I. C. Leão , B. Delabre

Precise astronomical spectroscopic analyses routinely assume that individual pixels in charge-coupled devices (CCDs) have uniform sensitivity to photons. Intra-pixel sensitivity (IPS) variations may already cause small systematic errors in,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Michael T. Murphy , Clayton R. Locke , Philip S. Light , Andre N. Luiten , Jon S. Lawrence

Pulsar dynamic spectra sometimes show organised interference patterns; these patterns have been shown to have power spectra which often take the form of parabolic arcs, or sequences of inverted parabolic arclets whose apexes themselves…

Astrophysics · Physics 2009-11-10 Mark Walker , Don Melrose , Dan Stinebring , Chengmin Zhang