J/MNRAS/473/4436 Spectral properties of 441 radio pulsars (Jankowski+, 2018)
Spectral properties of 441 radio pulsars.
Jankowski F., Van Straten W., Keane E.F., Bailes M., Barr E.D.,
Johnston S., Kerr M.
<Mon. Not. R. Astron. Soc., 473, 4436-4458 (2018)>
=2018MNRAS.473.4436J 2018MNRAS.473.4436J (SIMBAD/NED BibCode)
ADC_Keywords: Models ; Pulsars ; Radio continuum ; Radio sources ;
Spectral types
Keywords: radiation mechanisms: non-thermal - methods: data analysis -
pulsars: general - radio continuum: stars
Abstract:
We present a study of the spectral properties of 441 pulsars observed
with the Parkes radio telescope near the centre frequencies of 728,
1382 and 3100MHz. The observations at 728 and 3100MHz were conducted
simultaneously using the dual-band 10-50cm receiver. These
high-sensitivity, multifrequency observations provide a systematic and
uniform sample of pulsar flux densities. We combine our measurements
with spectral data from the literature in order to derive the spectral
properties of these pulsars. Using techniques from robust regression
and information theory, we classify the observed spectra in an
objective, robust and unbiased way into five morphological classes:
simple or broken power law, power law with either low- or
high-frequency cut-off and log-parabolic spectrum. While about 79 per
cent of the pulsars that could be classified have simple power-law
spectra, we find significant deviations in 73 pulsars, 35 of which
have curved spectra, 25 with a spectral break and 10 with a
low-frequency turn-over. We identify 11 gigahertz-peaked spectrum
(GPS) pulsars, with 3 newly identified in this work and 8
confirmations of known GPS pulsars; 3 others show tentative evidence
of GPS, but require further low-frequency measurements to support this
classification. The weighted mean spectral index of all pulsars with
simple power-law spectra is -1.60±0.03. The observed spectral
indices are well described by a shifted log-normal distribution. The
strongest correlations of spectral index are with spin-down
luminosity, magnetic field at the light-cylinder and spin-down rate.
We also investigate the physical origin of the observed spectral
features and determine emission altitudes for three pulsars.
Description:
We present spectral parameters for 441 radio pulsars. These were
obtained from observations centred at 728, 1382 and 3100MHz using the
10-50cm and the 20cm multibeam receiver at the Parkes radio
telescope. In particular, we list the pulsar names (J2000), the
calibrated, band-integrated flux densities at 728, 1382 and 3100MHz,
the spectral classifications, the frequency ranges the spectral
classifications were performed over, the spectral indices for pulsars
with simple power-law spectra and the robust modulation indices at all
three centre frequencies for pulsars of which we have at least six
measurement epochs. The flux density uncertainties include
scintillation and a systematic contribution, in addition to the
statistical uncertainty. Upper limits are reported at the 3σ
level and all other uncertainties at the 1σ level.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablec1.dat 146 441 Spectral parameters for 441 radio pulsars
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Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- PSRJ Pulsar name (J2000) (JHHMM+DDMMA)
13 A1 --- l_S728 ? Limit flag on S728
14- 20 F7.2 mJy S728 ? Flux density at 728MHz
22- 27 F6.2 mJy e_S728 ? Uncertainty of flux density at 728MHz
29 A1 --- l_S1382 ? Limit flag on S1382
30- 37 F8.3 mJy S1382 ? Flux density at 1382MHz
39- 44 F6.3 mJy e_S1382 ? Uncertainty of flux density at 1382MHz
46 A1 --- l_S3100 ? Limit flag on S3100
47- 53 F7.3 mJy S3100 ? Flux density at 3100MHz
55- 60 F6.3 mJy e_S3100 ? Uncertainty of flux density at 3100MHz
62- 74 A13 --- Class ? Spectral classification of pulsar
76- 79 F4.2 GHz nu-start Frequency range start for classification
81- 84 F4.1 GHz nu-end Frequency range end for classification
86- 90 F5.2 --- alpha ? Spectral index for simple pl spectra
92- 95 F4.2 --- e_alpha ? Uncertainty of spectral index
97-100 F4.2 --- m728 ? Robust modulation index at 728MHz
102-105 F4.2 --- e_m728 ? Low uncertainty on m728
107-110 F4.2 --- E_m728 ? High uncertainty on m728
112-116 F5.3 --- m1382 ? Robust modulation index at 1382MHz
118-122 F5.3 --- e_m1382 ? Low uncertainty on m1382
124-128 F5.3 --- E_m1382 ? High uncertainty on m1382
130-134 F5.3 --- m3100 ? Robust modulation index at 3100MHz
136-140 F5.3 --- e_m3100 ? Low uncertainty on m3100
142-146 F5.3 --- E_m3100 ? High uncertainty on m3100
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Acknowledgements:
Fabian Jankowski, fjankowsk at gmail.com
(End) F. Jankowski [Manchester Univ., UK], P. Vannier [CDS] 29-Mar-2018