V. V. Oreshko

Giant Pulses—the Main Component of the Radio Emission of the Crab Pulsar

The paper presents an analysis of dual-polarization observations of the Crab pulsar obtained on the 64-m Kalyazin radio telescope at 600 MHz with a time resolution of 250 ns. A lower limit for the intensities of giant pulses is estimated by assuming that the pulsar radio emission in the main pulse and interpulse consists entirely of giant radio pulses; this yields estimates of 100 and 35 Jy for the peak flux densities of giant pulses arising in the main pulse and interpulse, respectively. This assumes that the normal radio emission of the pulse occurs in the precursor pulse. In this case, the longitudes of the giant radio pulses relative to the profile of the normal radio emission turn out to be the same for the Crab pulsar and the millisecond pulsar B1937+21, namely, the giant pulses arise at the trailing edge of the profile of the normal radio emission. Analysis of the distribution of the degree of circular polarization for the giant pulses suggests that they can consist of a random mixture of nanopulses with 100% circular polarization of either sign, with, on average, hundreds of such nanopulses within a single giant pulse.

Pulsar VLBI experiment with the Kashima (Japan)–Kalyazin (Russia) baseline

Abstract The position of PSR0329+54 on the International Celestial Reference Frame was measured at epochs March 1995, May 1996, and May 1998. Our observations detected the proper motion of PSR0329+54. The position and proper motion agreed well with the position determined by Bartel et al. (1985) . From combined analysis with our data and that of Bartel, the proper motion of PSR0329+54 was determined: μ α =+17.4±0.3 mas yr −1 , μ δ =−11.0±0.3 mas yr −1 . These results are consistent with the value by Harrison et al. (1993) measured with the MERLIN interferometer. We also determined the coordinates of PSR0329+54 very accurately within the ICRF: α =03 h 32 m 59 s .3761±0 s .0002, δ =54°34′43′′.5119±0′′.0015 at 1995.

Detection of Five New RRATs at 111 MHz

Results of 111-MHz monitoring observations carried out on the Big Scanning Antenna of the Pushchino Radio Astronomy Observatory during September 1–28, 2015 are presented. Fifty-four pulsating sources were detected at declinations −9° < δ < 42°. Forty-seven of these are known pulsars, five are new sources, and two are previously discovered transients. Estimates of the peak flux densities and dispersion measures are presented for all these sources.

Pulsar timing at Kalyazin (Russia)

Regular timing observations of millisecond and binary pulsars are made with the 64-m radio telescope at Kalyazin (Russia). Filterbank 160-channel receiver is used for observations at 0.6 GHz in two circular orthogonal polarization. Precise local time service (based upon a rubidium standards and hydrogen maser) is used for measurements of Times-of-Arrival (TOA) from radio pulsars. A local time scale is compared by GPS and TV-systems with the basic AT-scales (UTC(USNO) and UTC(SU)) within an accuracy about 50 ns per day. Recently the second 1.4 GHz receiver (250 kHz × 64 channels) was constructed and installed at Kalyazin radio telescope. There is a possibility to combine a part of the 1.4 GHz back-end with the 2.2 GHz front-end to produce timing observations at three frequencies simultaneously. We present a results of precise timing observations conducted by the Kalyazin pulsar system. Most of data were obtained at 0.6 GHz in 1997–1999. The data will be used for valuable applications in fundamental metrology, interstellar medium, general relativity and pulsar physics itself.

FIRST RESULTS OF MILLISECOND PULSAR 1937+21 TIMING BY TNA-1500 RADIO TELESCOPE OF SPECIAL RESEARCH BUREAU OF MOSCOW POWER ENGINEERING INSTITUTE

Regular timing observations of the millisecond pulsar PSR 1937+21 at a frequency of 610 MHz by means of the TNA-1500 radio telescope with a fully steerable 64-m antenna have begun at the Bear Lakes Radio Observatory of the Special Research Bureau of the Moscow Power Engineering Institute. A 40-channel spectrum analyzer and a system for high-speed recording and acquisition of observation data are connected to a reference clock by means of CAMAC interfaces and an 80286 control computer. The reception band is 1.6 MHz (40 channels of 40 kHz each). The total noise temperature of the system is on the order of 160 K. The signal-to-noise ratio is on the order of 50 for a 30-min observation of the pulsar. The mean-square error of measurement of the pulse arrival time is 400 nsec. Data on pulsar 1937+21 along with timing results for “normal” reference pulsars PSR 0834+06 and PSR 1919+21 obtained at the Pushino Radio Observatory of the Lebedev Physics Institute over a period of 13 years will be used to construct a pulsar time scale.

Synchronizing the time and frequency standards at the Radio Astronomy Station, Physics Institute, USSR Academy of Sciences, with the state standard for time and frequency

The pulsar time scale [i, 2] is based on the pulsed radio emission from pulsars such as PSR 1937 + 214 (millisecond range), which imposes new requirements on the time service at the Radio Astronomy Station [3]. The standard deviation in the residual deviations in the time of arrival from the precalculated course is less than i Dsec [4]. In this connection, the error in the local time scale at the station should be less than I Dsec relative to that of the state standard of frequency and time in the USSR. For that purpose, the time and frequency service at the station has been equipped with high-stability quantum time and frequency standards and precision apparatus for matching them to the state scale.