Search Publications
Antarctic Survey Telescope 3-3: Overview, System Performance and Preliminary Observations at Yaoan, Yunnan
Wang, Lifan; Hu, Lei; Hu, Maokai +17 more
The third Antarctic Survey Telescope array instrument at Dome A in Antarctica, the AST3-3 telescope, has been in commissioning from March 2021. We deployed AST3-3 at the Yaoan astronomical station in Yunnan Province for an automatic time-domain survey and follow-up observations with an optimised observation and protection system. The telescope sys…
Assessment of Dark Matter Models Using Dark Matter Correlations across Dwarf Spheroidal Galaxies
Borzou, Ahmad
The predicted size of dark matter substructures in kilo-parsec scales is model-dependent. Therefore, if the correlations between dark matter mass densities as a function of the distances between them are measured via observations, we can scrutinize dark matter scenarios. In this paper, we present an assessment procedure of dark matter scenarios. F…
Determination of the Physical Parameters of AGNs in Seyfert 1 Galaxies LEDA 3095839 and VII Zw 244 Based on Spectropolarimetric Observations
Shablovinskaya, Elena; Piotrovich, Mikhail; Malygin, Eugene +2 more
Here we present the detailed investigation of AGNs in two Seyfert 1 galaxies, LEDA 3095839 and VII Zw 244. Both of them were observed within the photometric reverberation mapping project in Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS), during which we earlier obtained the SMBHs masses. After that, both galaxies we…
Description and Application of the Surfing Effect
Nucita, Achille A.; De Paolis, Francesco; Maiorano, Michele
The standard technique for very low-frequency gravitational wave detection is mainly based on searching for a specific spatial correlation in the variation of the times of arrival of the radio pulses emitted by millisecond pulsars with respect to a timing model. This spatial correlation, which in the case of the gravitational wave background must …
Study of Intra-Day Flux Distributions of Blazars Using XMM-Newton Satellite
Gaur, Haritma; Wani, Kiran
We present a study of the flux distribution of a sample of 15 Intermediate and Low-energy peaked blazars using XMM-Newton observations in a total of 57 epochs on short-term timescales. We characterise the X-ray variability of all of the light curves using excess fractional variability amplitude and found that only 24 light curves in 7 sources are …
Multiwavelength Observations of Fast Radio Bursts
Zampieri, Luca; Turatto, Massimo; Nicastro, Luciano +3 more
The origin and phenomenology of the Fast Radio Burst (FRB) remains unknown despite more than a decade of efforts. Though several models have been proposed to explain the observed data, none is able to explain alone the variety of events so far recorded. The leading models consider magnetars as potential FRB sources. The recent detection of FRBs fr…
Space-Based Photometry of Binary Stars: From Voyager to TESS
Southworth, John
Binary stars are crucial laboratories for stellar physics, so have been photometric targets for space missions beginning with the very first orbiting telescope (OAO-2) launched in 1968. This review traces the binary stars observed and the scientific results obtained from the early days of ultraviolet missions (OAO-2, Voyager, ANS, IUE), through a …
Multi-Wavelength Properties of the 2021 Periastron Passage of PSR B1259-63
Santangelo, Andrea; Pühlhofer, Gerd; Chernyakova, Maria +9 more
PSR B1259-63 is a gamma-ray binary system hosting a radio pulsar orbiting around a O9.5Ve star, LS 2883, with a period of ∼3.4 years. The interaction of the pulsar wind with the LS 2883 outflow leads to unpulsed broadband emission in the radio, X-ray, GeV, and TeV domains. One of the most unusual features of the system is an outburst of GeV energi…
Project MOMO: Multiwavelength Observations and Modeling of OJ 287
Ciprini, S.; Komossa, S.; Gallo, L. C. +9 more
Our project MOMO (Multiwavelength observations and modeling of OJ 287) consists of dedicated, dense, long-term flux and spectroscopic monitoring, and deep follow-up observations of the blazar OJ 287 at >13 frequencies from the radio to the X-ray band since late 2015. In particular, we are using Swift to obtain optical-UV-X-ray spectral energy d…
Blocks Size Frequency Distribution in the Enceladus Tiger Stripes Area: Implications on Their Formative Processes
Lucchetti, Alice; Pajola, Maurizio; Cremonese, Gabriele +1 more
We study the size frequency distribution of the blocks located in the deeply fractured, geologically active Enceladus South Polar Terrain with the aim to suggest their formative mechanisms. Through the Cassini ISS images, we identify ~17,000 blocks with sizes ranging from ~25 m to 366 m, and located at different distances from the Damascus, Baghda…