Pulsar spectra of radio emission

نویسنده

  • Richard Wielebinski
چکیده

We have collected pulsar flux density observations and compiled spectra of 281 objects. The database of Lorimer et al. (1995) has been extended to frequencies higher than 1.4 GHz and lower than 300 MHz. Our results show that above 100 MHz the spectra of the majority of pulsars can be described by a simple power law with average value of spectral index < α >= −1.8 ± 0.2. A rigorous analysis of spectral fitting revealed only about 5% of spectra which can be modelled by the two power law. Thus, it seems that single power law is a rule and the two power law spectrum is a rather rare exception, of an unknown origin, to this rule. We have recognized a small number of pulsars with almost flat spectrum (α ≥ −1.0) in the wide frequency range (from 300 MHz to 20 GHz) as well as few pulsars with a turn-over at unusually high frequency (∼ 1 GHz).

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Hadronic model for radio - to - TeV γ - ray emission from PSR B 1259

We discuss the implications of the recent Xray and TeV γ-ray observations of the PSR B1259–63 system (a young rotation powered pulsar orbiting a Be star) for the theoretical models of interaction of pulsar and stellar winds. We show that previously considered models in which the pulsar wind is purely electron loaded have problems to account for the observed behaviour of the system in the TeV an...

متن کامل

Geometrical effects on radio pulsar profiles and spectra

Considering the geometry of the hollow-cone model of radio pulsar emission in detail, one is led to the conclusion that severalwell-knownobserved effectsmay be explained quite easily purely on geometrical terms. It can be shown e.g. that the appearance of outriders at high frequencies and a steepening of the whole spectrum (cut-off) must be expected for certain geometrical situations as well as...

متن کامل

Fluctuation Properties and Polar Emission Mapping of Pulsar B0834+06 at Decameter Wavelengths

Recent results regarding subpulse-drift in pulsar B0943+10 have led to the identification of a stable system of sub-beams circulating around the magnetic axis of the star. Here, we present single-pulse analysis of pulsar B0834+06 at 35 MHz, using observations from the Gauribidanur Radio Telescope. Certain signatures in the fluctuation spectra and correlations allow estimation of the circulation...

متن کامل

Particle Acceleration in Pulsar Wind Nebulae

Plerionic supernova remnants exhibit radio emission with remarkably flat spectral indices ranging from α = 0.0 to α = −0.3. The origin of very hard particle energy distributions still awaits an explanation, since shock waves generate particle distributions with synchrotron spectra characterized by α ≤ −0.5. Acceleration of high energy leptons in magnetohydrodynamic turbulence instead may be res...

متن کامل

Comptonization in the X-ray Spectra of Radio Millisecond Pulsars

The majority of X-ray-detected rotationpowered millisecond pulsars (MSPs) appear to exhibit predominantly thermal emission, believed to originate from the heated magnetic polar caps of the pulsar. In the nearest MSP, J0437–4715 a faint PL is also observed at >3 keV, usually associated with magnetospheric emission processes. However, the hard emission in this and other similar MSPs may instead b...

متن کامل

Amazing properties of giant pulses and the nature of pulsar’s radio emission

For comprehensive studying of giant pulses (GPs) from the Crab pulsar and the original millisecond pulsar (MSP) B1937+21 (J1939+2134), we conducted multifrequency observations over the last few years. They show that giant pulses may be improbably bright, 10, 10 Jy and more, they have extra ordinal spectra and polarization. EM energy concentrated in such strong pulse is high enough to accelerate...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2000