We presented the results of last years GRB observations obtained on the MASTER robotic telescope, which is the only telescope of its kind in Russia. These results include 5 prompt observations of GRB ...in 2008 and 2009, follow-up observations of 15 other GRBs in 2008-2009, the first observations in different polarization angles of optical emission from the gamma-ray bursts GRB091020, and observations in different polarization angles for GRB091127 and GRB090820.
Abstract
The SNAD team has developed an adaptive learning algorithm, named Pine Forest (PF), to enhance anomaly detection in astronomical data. Recognizing the essential role of human engagement in ...the discovery process, PF presents outliers to a human expert for review, and filters out trees which disagree with the feedback provided. During the sixth annual SNAD workshop (
https://snad.space/2023/
), held in 2023 July, we applied PF to the Zwicky Transient Facility’s DR17 data. Interesting discoveries include long-duration objects such as supernovae, along with fast transients like red dwarf flares and one microlensing event. As a result, new variable stars were identified and labeled in the SNAD knowledge database.
KPS-1b Burdanov, Artem; Benni, Paul; Sokov, Eugene ...
Publications of the Astronomical Society of the Pacific,
07/2018, Letnik:
130, Številka:
989
Journal Article
Recenzirano
We report the discovery of the transiting hot Jupiter KPS-1b. This exoplanet orbits a V = 13.0 K1-type mainsequence star every 1.7 days, has a mass of
1.090
−
0.087
+
0.086
M
Jup and a radius of
1.03
...−
0.12
+
0.13
R
Jup. The discovery was made by the prototype Kourovka Planet Search (KPS) project, which used wide-field CCD data gathered by an amateur astronomer using readily available and relatively affordable equipment. Here we describe the equipment and observing technique used for the discovery of KPS-1b, its characterization with spectroscopic observations by the SOPHIE spectrograph and with high-precision photometry obtained with 1 m class telescopes. We also outline the KPS project evolution into the Galactic Plane eXoplanet survey. The discovery of KPS-1b represents a new major step of the contribution of amateur astronomers to the burgeoning field of exoplanetology.
Presented paper describes the basic principles and features of the implementation of a robotic network of optical telescopes MASTER, designed to study the prompt (simultaneous with gamma radiation) ...optical emission of gamma-ray bursts and to perform the sky survey to detect unknown objects and transient phenomena. With joint efforts of Sternberg astronomical institute, High altitude astronomical station of the Pulkovo observatory, Ural state university, Irkutsk state university, Blagoveshchensk pedagogical university, the robotic telescopes MASTER II near Kislovodsk, Yekaterinburg, Irkutsk and Blagoveshchensk were installed and tested. The network spread over the longitudes is greater than 6 h. A further expansion of the network is considered.
We provide the first results from the complete SNAD adaptive learning pipeline in the context of a broad scope of data from large-scale astronomical surveys. The main goal of this work is to explore ...the potential of adaptive learning techniques in application to big data sets. Our SNAD team used Active Anomaly Discovery (AAD) as a tool to search for new supernova (SN) candidates in the photometric data from the first 9.4 months of the Zwicky Transient Facility (ZTF) survey, namely, between March 17 and December 31 2018 (58194 < MJD < 58483). We analysed 70 ZTF fields at a high galactic latitude and visually inspected 2100 outliers. This resulted in 104 SN-like objects being found, 57 of which were reported to the Transient Name Server for the first time and with 47 having previously been mentioned in other catalogues, either as SNe with known types or as SN candidates. We visually inspected the multi-colour light curves of the non-catalogued transients and performed fittings with different supernova models to assign it to a probable photometric class: Ia, Ib/c, IIP, IIL, or IIn. Moreover, we also identified unreported slow-evolving transients that are good superluminous SN candidates, along with a few other non-catalogued objects, such as red dwarf flares and active galactic nuclei. Beyond confirming the effectiveness of human-machine integration underlying the AAD strategy, our results shed light on potential leaks in currently available pipelines. These findings can help avoid similar losses in future large-scale astronomical surveys. Furthermore, the algorithm enables direct searches of any type of data and based on any definition of an anomaly set by the expert.
We analyze the dust environment of the distant comet C/2014 A4 (SONEAR), with a perihelion distance near 4.1~au, using comprehensive observations obtained by different methods. We present an analysis ...of spectroscopy, photometry, and polarimetry of comet C/2014 A4 (SONEAR), which were performed on November 5~--~7, 2015, when its heliocentric distance was 4.2~au and phase angle was 4.7\(^\circ\). Long-slit spectra and photometric and linear polarimetric images were obtained using the focal reducer SCORPIO-2 attached to the prime focus of the 6-m telescope BTA (SAO RAS, Russia). We simulated the behavior of color and polarization in the coma presenting the cometary dust as a set of polydisperse polyshapes rough spheroids. No emissions were detected in the 3800~--~7200~\(\AA\) wavelength range. The continuum showed a reddening effect with the normalized gradient of reflectivity 21.6\(\pm\)0.2\% per 1000~\(\AA\) within the 4650~--~6200~\(\AA\) wavelength region. The fan-like structure in the sunward hemisphere was detected. The radial profiles of surface brightness differ for r-sdss and g-sdss filters, indicating predominance of submicron and micron-sized particles in cometary coma. The dust color (g--r) varies from 0.75\( \pm \)0.05\(^m\) to 0.45\( \pm \)0.06\(^m\) along the tail. For aperture radius near 20~000~km, the dust productions in various filters were estimated as \(Af\rho \)~=~680\(\pm\)18~cm (r-sdss) and 887\( \pm \)16~cm (g-sdss). The polarization map showed spatial variations of polarization over the coma from about --3\% near the nucleus to --8\% at cometocentric distance about 150~000~km. Our simulations show that the dust particles were dominated (or covered) by ice and tholin-like organics. Spatial changes in the color and polarization can be explained by particle fragmentation.
We report the discovery of a relatively bright eclipsing binary system, which consists of a white dwarf and a main sequence K7 star with clear signs of chromospheric and spot activity. The light ...curve of this system shows \(\sim0.2\)mag ellipsoidal variability with a period of 0.297549d and a short total eclipse of the white dwarf. Based on our analysis of the spectral and photometric data, we estimated the parameters of the system. The K7V star is tidally deformed but does not fill its Roche lobe (the filling factor is about 0.86). The orbital inclination is \(i=73^\circ.1\pm 0^\circ.2\), the mass ratio is \(q=M_2/M_1\approx 0.88\). The parameters of the K7V star are \(M_2\approx 0.64\)M\(_{\odot}\), \(R_2=0.645\pm 0.012\)R\(_{\odot}\), \(T_2\approx 4070\)K. The parameters of the white dwarf are \(M_1\approx 0.72\)M\(_{\odot}\), \(R_1=0.013\pm 0.003\)R\(_{\odot}\), \(T_1=8700\pm 1100\)K. Photometric observations in different bands revealed that the maximum depth of the eclipse is in the \textit{SDSS r} filter, which is unusual for a system of a white dwarf and a late main sequence star. We suspect that this system is a product of the evolution of a common envelope binary star, and that the white dwarf accretes the stellar wind from the secondary star (the so-called low-accretion rate polar, LARP).
We present TOI-1259Ab, a 1.0 Rjup gas giant planet transiting a 0.71 Rsun K-dwarf on a 3.48 day orbit. The system also contains a bound white dwarf companion TOI-1259B with a projected distance of ...approximately 1600 AU from the planet host. Transits are observed in nine TESS sector and are 2.7 per cent deep - among the deepest known - making TOI-1259Ab a promising target for atmospheric characterization. Our follow-up radial velocity measurements indicate a variability of semiamplitude K = 71 m/s, implying a planet mass of 0.44 Mjup. By fitting the spectral energy distribution of the white dwarf we derive a total age of 4.08 (+1.21 -0.53) Gyr for the system. The K-dwarf's light curve reveals a rotational variability with a period of 28 days, which implies a gyrochronology age broadly consistent with the white dwarf's total age.
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