Article
Astronomy & Astrophysics
L. Dunn, A. Melatos, C. M. Espinoza, D. Antonopoulou, R. Dodson
Summary: A study is conducted to better understand the small glitches in Vela pulsar using high-cadence observations from the Mount Pleasant Observatory. A hidden Markov model is utilized to search for previously undetected glitches and estimates their parameters. The study also sets upper limits on the sizes of missed glitches, providing crucial information for studying small glitches.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
C. M. Espinoza, D. Antonopoulou, R. Dodson, M. Stepanova, A. Scherer
Summary: This study explores the occurrence and sizes of small glitches in the Vela pulsar, finding two previously unreported glitch events. Additionally, numerous small glitch events were identified, contributing to the pulsar's timing noise. The Vela pulsar shows an under-abundance of small glitches compared to other glitching pulsars, with a smooth spin-down process affected by continuous small step-like changes.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Q. Liu, W. Wang, X. Chen, Y. Z. Ding, F. J. Lu, L. M. Song, J. L. Qu, S. Zhang, S. N. Zhang
Summary: We conducted a detailed study of Vela X-1, a high-mass X-ray binary, using observations from Insight-HXMT in 2019 and 2020. Our analysis focused on timing analysis and spectral studies, including pulse phase-resolved spectroscopy. The cyclotron line energy was found to be 21-27 keV for the fundamental and 43-50 keV for the first harmonic. The study showed that the fundamental line energy correlates with X-ray luminosity, indicating that Vela X-1 is in the sub-critical accreting regime. The pulse phase-resolved spectroscopy revealed significant variability in both the cyclotron resonant scattering feature and continuum parameters, as well as long-term variations in the absorption column density over the pulse phase, possibly suggesting the presence of a clumpy wind structure near the neutron star.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
A. N. Kazantsev, M. Yu Basalaeva
Summary: The article presents the results of an investigation into the giant radio pulse (GRP) generation rate and anomalous intensity pulse generation rate from several radio pulsars. It analyzes the rates of generation of bright pulses, the distribution of bright pulses in the pulsar period, and the existence of clusters of bright pulses. The study finds that different pulsars demonstrate varying generation rates and generation of clusters, with one pulsar generating GRP clusters more frequently than others.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Fengqiu Adam Dong, Kathryn Crowter, Bradley W. Meyers, Ziggy Pleunis, Ingrid Stairs, Chia Min Tan, Tinyau Timothy Yu, Patrick J. Boyle, Amanda M. Cook, Emmanuel Fonseca, B. M. Gaensler, Deborah C. Good, Victoria Kaspi, James W. McKee, Chitrang Patel, Aaron B. Pearlman
Summary: The Canadian Hydrogen Mapping Experiment (CHIME) is a radio telescope in Canada that is capable of identifying new Galactic sources such as pulsars and rotating radio transients (RRATs). With its large field of view, CHIME/FRB can efficiently locate these objects, and follow-up observations can be conducted with the more sensitive CHIME/Pulsar instrument to obtain detailed data. Through this process, 21 new Galactic sources have been discovered, including RRATs and pulsars, providing further insights into these celestial objects.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Lin-Li Yan, Ming-Yu Ge, You-Li Tuo, Ling-jun Wang, Qing-yong Zhou
Summary: We analyze the time and energy dependence of the Vela pulsar's pulse profile and find that it changes with time and shows clear energy dependence. Different shape parameters exhibit fluctuations rather than gradual changes with time, and their energy evolution is quantified for the first time. This study provides important restrictions on current gamma-ray emission models.
RESEARCH IN ASTRONOMY AND ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
C. M. Tan, M. Rigoselli, P. Esposito, B. W. Stappers
Summary: We conducted a deep XMM-Newton observing campaign on PSR J0250 + 5854 to study the relationship between long-period, radio-emitting neutron stars and their high-energy-emitting counterparts. No X-ray emission was detected, indicating a low bolometric luminosity compared to other XDINSs. The comparison with SGR 0418+5729 suggests that PSR J0250 + 5854 might have a lower blackbody temperature if it has a similar thermal hotspot.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
J. L. Chen, Z. G. Wen, X. F. Duan, D. L. He, N. Wang, H. G. Wang, R. Yuen, J. P. Yuan, W. M. Yan, Z. Wang, C. B. Lyu, H. Wang, S. R. Cui
Summary: In this study, we analyze the radio emission from the pulsar J1401-6357 (B1358-63) using data from the Parkes radio telescope. The pulse profile shows a weak leading component and a single-humped structure with slight asymmetry. Nulls are observed across the entire frequency band, with an estimated nulling fraction greater than 2 percent. The presence of temporal-dependent subpulse drifting and a double-peaked feature at the alias border suggest global magnetospheric changes.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
S. A. Suleymanova, A. N. Kazantsev, J. M. Rankin, S. Logvinenko
Summary: The study reports a gradual shift of integrated pulses towards later spin phase of the anomalous pulsar B0943+10 at high radio frequencies, using observations from the Arecibo Observatory and the GMRT. A special method was proposed to calculate correct positions of partially merged pulse profile components, revealing an exponential change in pulse phase. The process was found to be independent of frequency across a wide range, supporting the hypothesis that it results from changes in the vacuum gap near the pulsar's surface.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
S. Logvinenko, Joanna M. Rankin, S. A. Suleymanova
Summary: This study reports on the transitional intervals between pulsar B0943+10's two primary emission modes. Similar patterns of subpulse drift and profile form were observed at 327 MHz as at lower frequencies during the Q-to-B mode transition process. Additionally, the study examined pulse polarization variations in the main modes.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Amar Deo Chandra, Jayashree Roy, P. C. Agrawal, Manojendu Choudhury
Summary: The study reveals nearly periodic variations in the spin period of the high-mass X-ray binary pulsar Vela X-1, indicating cyclic turnover from spin-up to spin-down regimes. This periodic behavior may be attributed to changes in the accretion environment of the pulsar.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Angiraben D. Mahida, J. L. Palfreyman, G. Molera Calves, Susmita Sett
Summary: This study examines the Vela pulsar (PSR J0835-4510), which has been the subject of research for many years. By analyzing nearly 100 hours of single-pulse data collected over three consecutive days in 2016 and 2020, researchers discovered a hyperbolic relation between the earlier arrival of brighter pulses and their peak intensity. By constructing integrated pulse profiles and examining the relationship between pulse arrival time and intensity, a phase limit of -0.85 ± 0.0109 ms was identified for the earliest arrival of the brightest pulses. This study presents exciting prospects for further exploration of the emission regions responsible for the regular pulses and giant micro-pulses of the Vela pulsar.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
A. S. Tanashkin, A. Karpova, A. Y. Potekhin, Y. A. Shibanov, D. A. Zyuzin
Summary: XMM-Newton observations of the middle-aged radio-quiet gamma-ray pulsar J0554+3107 allowed us to identify it in X-rays for the first time. The pulse profile shows two peaks separated by about a half of the rotation phase, with a pulsed fraction of 25+/- 6% in the 0.2-2 keV band. The profile and spectrum can be described by thermal emission from the neutron star with a hydrogen atmosphere and a dipole magnetic field of around 10(13) G.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
D. A. Zyuzin, A. Karpova, Y. A. Shibanov, A. Y. Potekhin, V. F. Suleimanov
Summary: The study confirms the pulsar nature of J1957+5033 through the detection of X-ray pulsations, the pulsar's spectrum is dominated by a thermal emission component, and new hydrogen atmosphere models are constructed to analyze the pulsar's average effective temperature. Additionally, a faint trail-like feature potentially powered by J1957+5033 in the form of a pulsar wind nebula is observed in the X-ray observations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Parul Janagal, Manoneeta Chakraborty, N. D. Ramesh Bhat, Bhaswati Bhattacharyya, Samuel J. McSweeney
Summary: In this study, we conducted a detailed investigation of subpulse drifting in PSR J1822-2256 using the upgraded Giant Meterwave Radio Telescope (uGMRT). Our observations revealed four distinct subpulse drifting modes and identified new features not previously reported. We also explored the frequency dependence of the pulsar emission and discussed its implications for the emission mechanism and spark configuration.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
S. Zharikov, D. Zyuzin, Yu Shibanov, A. Kirichenko, R. E. Mennickent, S. Geier, A. Cabrera-Lavers
Summary: This study reports the detection of PSR B0656+14 using the Gran Telescopio Canarias, expanding its spectrum to 2.2 microns. Through analysis of optical and X-ray data, the surface temperature and emitting region radius of the pulsar were derived, while spectral features and variations in non-thermal emission were also discovered.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
D. A. Zyuzin, A. Karpova, Y. A. Shibanov, A. Y. Potekhin, V. F. Suleimanov
Summary: The study confirms the pulsar nature of J1957+5033 through the detection of X-ray pulsations, the pulsar's spectrum is dominated by a thermal emission component, and new hydrogen atmosphere models are constructed to analyze the pulsar's average effective temperature. Additionally, a faint trail-like feature potentially powered by J1957+5033 in the form of a pulsar wind nebula is observed in the X-ray observations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
P. Lundqvist, N. Lundqvist, Yu A. Shibanov
Summary: The aim of this study is to investigate the structure, elemental abundances, physical conditions, and surroundings of supernova remnant 0540-69.3 in the Large Magellanic Cloud. Imaging and spectroscopic studies were conducted using telescopes of the European Southern Observatory. The results reveal new spectral lines, estimate densities, temperatures, and abundances, and provide insights into the characteristics of the remnant.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Vadim Abramkin, George G. Pavlov, Yuriy Shibanov, Oleg Kargaltsev
Summary: Based on recent observations, a thermal component has been revealed in the spectrum of the old pulsar B0950+08, with an estimated surface temperature of (1-3) x 10(5) K. New optical observations have shown a flatter slope of the spectrum compared to ground-based observations, with a lower temperature than previously reported but still higher than predicted.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
D. A. Zyuzin, S. Zharikov, A. Karpova, A. Yu Kirichenko, Yu A. Shibanov, S. Geier, A. Y. Potekhin, V. F. Suleimanov, A. Cabrera-Lavers
Summary: This article introduces an 840,000-year-old pulsar PSR J1957+5033. Optical observations were conducted using a 10.4-metre telescope, and a potential optical counterpart was discovered. Analysis suggests that thermal emission from the surface of the neutron star has a significant contribution to the optical flux. This reveals the potential of optical data in providing new constraints on the temperature and distance of pulsars.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
S. A. Khokhlov, A. S. Miroshnichenko, S. Zharikov, K. N. Grankin, O. Zakhozhay, N. Manset, A. A. Arkharov, N. Efimova, S. Klimanov, V. M. Larionov, A. A. Khokhlov, A. Kusakin, C. T. Omarov, R. Kokumbaeva, I. Reva, A. T. Agishev
Summary: The results of spectroscopic and photometric observations of the emission-line object IRAS 07080+0605 are reported. The object shows underluminosity for its spectroscopic properties and exhibits periodic variations in visual brightness and absorption-line positions, indicating that it is most likely a binary system.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
A. S. Tanashkin, A. Karpova, A. Y. Potekhin, Y. A. Shibanov, D. A. Zyuzin
Summary: XMM-Newton observations of the middle-aged radio-quiet gamma-ray pulsar J0554+3107 allowed us to identify it in X-rays for the first time. The pulse profile shows two peaks separated by about a half of the rotation phase, with a pulsed fraction of 25+/- 6% in the 0.2-2 keV band. The profile and spectrum can be described by thermal emission from the neutron star with a hydrogen atmosphere and a dipole magnetic field of around 10(13) G.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
A. S. Nodyarov, A. S. Miroshnichenko, S. A. Khokhlov, S. Zharikov, N. Manset, V. G. Klochkova, K. N. Grankin, A. A. Arkharov, N. Efimova, S. Klimanov, V. M. Larionov, R. J. Rudy, R. C. Puetter, R. B. Perry, I. Reva, C. T. Omarov, R. Kokumbaeva
Summary: We present the results of optical and near-IR spectroscopy and multicolor photometry of the emission-line star MWC645, indicating it is a binary system. The variability of absorption lines suggests the presence of a cool star. Analysis of photometric and spectroscopic data, along with Gaia EDR3 distance, allows us to estimate the temperatures and luminosities of the components. The object exhibits quasi-cyclic short-period and long-period photometric variations, likely due to variable circumstellar extinction, and is identified as a member of the FS CMa group.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Gagik Tovmassian, Boris T. Gansicke, Juan Echevarria, Sergey Zharikov, Abdiel Ramirez
Summary: V455 And is a dwarf nova with a short orbital period that underwent a unique superoutburst. The spectroscopic behavior during the rise and decline of the superoutburst suggests the presence of wind from the evaporating disk in this high-inclination system. This observation provides valuable evidence for understanding the dynamics in such systems.
ASTROPHYSICAL JOURNAL
(2022)
Review
Astronomy & Astrophysics
Anatoly S. Miroshnichenko, Sergei V. Zharikov, Nadine Manset, Serik A. Khokhlov, Atilkhan S. Nodyarov, Valentina G. Klochkova, Stephen Danford, Aizhan K. Kuratova, Ronald Mennickent, S. Drew Chojnowski, Ashish Raj, Devendra Bisht
Summary: This paper describes recent studies of the FS CMa-type objects, a group of stars with B[e] phenomenon defined in 2007. These objects exhibit strong emission-line spectra and IR excesses, which are difficult to explain in the framework of single star evolution. The hypothesis of mass transfer between binary system components is explored to explain the gaseous-and-dusty envelopes of FS CMa objects. Regular radial velocity variations and absorption lines of cool stars have been detected in some objects.
Article
Astronomy & Astrophysics
A. Karpova, D. A. Zyuzin, Yu A. Shibanov, M. R. Gilfanov
Summary: By studying the data, we find that the Fermi source 4FGL J2054.2+6904 is likely a member of the redback family, which consists of millisecond pulsars in tight binary systems with low-mass stellar companions. The optical spectral energy distribution suggests that it is a G2-G9-type star and the X-ray spectrum is well fitted by an absorbed power law.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
A. Bobakov, A. Karpova, S. Zharikov, A. Yu Kirichenko, Yu A. Shibanov, D. A. Zyuzin
Summary: This article presents the optical spectroscopy results of three binary millisecond pulsars, showing that the companions of J0621+2514 and J2317+1439 are DA-type white dwarfs with relatively high temperatures of 8600 +/- 200 and 9600 +/- 2000 K, respectively, while the companion of J2302+4442 is a cooler DA-type white dwarf with a temperature below 6000 K.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)