6/16/2023 0 Comments Pulse powerIt is known that to obtain an average pulsar profile, which is one of the basic characteristics of a pulsar, you need to accumulate several hundred, or better, several thousand pulses ( Lorimer & Kramer 2004). Because the appearance of pulses is unpredictable, and the time interval between detected pulses can reach up to several hours, a long-time observation is necessary for their statistic accumulation. Research into rotating radio transients is difficult. There are few comprehensive RRAT studies, and therefore it is not yet possible to discard any hypotheses. It is possible that different hypotheses are valid for different RRATs, and that RRAT is an intermediate class compared to different types of known pulsars. Thus, the only certain thing is that RRATs are a subclass of pulsars that are detected by the emission of their individual pulses, but the reason for this sporadic emission remains unclear. In the papers Li (2006) and Luo & Melrose (2007), it is assumed that RRATs are extinct pulsars that are turned of the interaction of the pulsar’s magnetosphere with the incident matter or the interaction of the magnetosphere with the surrounding matter. (2007), it is assumed that RRAT are an extreme type of mode-switching pulsars. For example, the source J0941-39 is, for part of the time, observed as a RRAT, and part of the time as pulsar. This work also shows that the hypothesis of giant pulses is not applicable for at least some of the observed fast radio transients. Thus, according to this hypothesis, RRATs represent a late evolutionary phase in the pulsar’s life. In the work of Burke-Spolaor & Bailes (2010), it is assumed that the duration of the “fading” window of pulsars increases in proportion to their lifetime. (2007), RRATs are pulsars with long (extreme) nullings. ![]() According to another hypothesis from Zhang et al. At the same time, the energy of individual giant pulses may be high enough to detect them. If the distance to a pulsar is great, the sensitivity of the radio telescope is not sufficient to detect periodic emission and to obtain an average profile. ![]() (2006), RRATs can be ordinary pulsars with “extreme bursts of radio emission”. There are several hypotheses that attempt to explain the irregularity of RRAT emission. The search for an evolutionary relationship between canonical pulsars and RRATs was considered in papers Keane & Kramer (2008) and Keane et al. It is still not completely clear whether these pulsars are the same objects as canonical pulsars. Time intervals between RRAT pulses can range from tens of seconds to hours. These pulsars were called rotating radio transients (RRATs). In 2006, pulsars were discovered that emitted irregular pulses ( McLaughlin et al. These pulses were similar to “weak sporadic interference” ( Hewish et al. The discovery of pulsars in 1967 was associated with the detection of regular (periodic) pulses of emission in the meter range of wavelengths. ![]() Analysis of the obtained data suggests that RRAT J0139+33 is a pulsar with giant pulses. We did not detect a regular (pulsar) emission of J0139+33. For the B0320+39 pulsar, the dependence is lognormal, and it turns into a power dependence at high values of S/N and for RRAT J0139+33, the distribution of pulses by energy is described by a broken (bimodal) power dependence with an exponent of about 0.4 and 1.8 ( S/ N ≤ 19 and S/ N ≥ 19). The distributions could be approximated with lognormal and power dependences. We obtained distributions of the number of detected pulses in S/N units for the pulsar and for the rotating transient. The signal-to-noise ratio (S/N) for the strongest registered pulses is, approximately, the following: S/ N = 262 (for B0320+39) and S/ N = 154 (for J0139+33). The share of registered pulses from the total number of observed periods for the pulsar B0320+39 is 74%, and for the transient J0139+33 it is 0.42%. At the interval ☑.5 m of the time corresponding to the source passing through the meridian, we detected 39377 individual pulses for the pulsar B0320+ pulses for RRAT J0139+33. Lebedev Physical Institute, Astro Space Center, Pushchino Radio Astronomy Observatory, 142290 Moscow region, RussiaĮ-mail: five-year-monitoring observations, we carried out a blind search for pulses for rotating radio transient (RRAT) J0139+33 and PSR B0320+39. Astronomical objects: linking to databases.Including author names using non-Roman alphabets.Suggested resources for more tips on language editing in the sciences Punctuation and style concerns regarding equations, figures, tables, and footnotes
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