J/MNRAS/449/1570 Multifrequency pulsar scatter time sample (Lewandowski+, 2015)
The analysis of the largest sample of multifrequency pulsar scatter time
estimates.
Lewandowski W., Kowalinska M., Kijak J.
<Mon. Not. R. Astron. Soc., 449, 1570-1583 (2015)>
=2015MNRAS.449.1570L 2015MNRAS.449.1570L (SIMBAD/NED BibCode)
ADC_Keywords: Pulsars
Keywords: scattering - pulsars: general - ISM: structure
Abstract:
We present our results of pulse broadening time estimates and the
study of the frequency scaling of this quantity for 60 pulsars based
on actual multifrequency scattering estimates. This research was based
on our own measurements, performed on the observational data and the
profiles from various pulsar profile data bases, as well as the
scatter time measurements that were found in the literature. We were
able to construct a data base of over 60 pulsars with true
multifrequency α measurements, which allowed us to revise the
previously proposed relations between the scatter time spectral slope
and the dispersion measure (DM). We found that the deviations from
theoretical predictions of the value of α appear for pulsars
regardless of their DM, however, the DM-averaged value of the scaling
index is almost constant except for pulsars with very high DMs. Based
on the obtained slopes we were also able to estimate the amount of
scattering at the standard frequency of 1GHz. We found that while the
estimated standardized pulse broadening time increases with DM the
relation seems to be much flatter than it was previously proposed,
which suggests higher values of the scatter time for mid-DM pulsars,
and lower values of expected pulse broadening for highly dispersed
sources.
Description:
To extend our the scatter time measurement data base published in
Paper I (Lewandowski et al., 2013MNRAS.434...69L 2013MNRAS.434...69L) we searched all
available literature, as well as added our own new measurements, both
based on available pulsar profile data bases, as well as from our own
observations performed with the GMRT (Pune, India) at the frequencies
of 325, 610 and 1170MHz.
The new GMRT observations were conducted between 2010 and 2012 as a
part of our ongoing project to search for the gigahertz-peaked spectra
pulsars (Kijak et al., 2011A&A...531A..16K 2011A&A...531A..16K; Dembska et al.,
2014MNRAS.445.3105D 2014MNRAS.445.3105D). We used 16-MHz bandwidth of GMRT working in
phased array mode, 0.512ms sampling rate and 256 spectral channels.
In this table, we present the results of the scatter time
measurements, both our own as well as the ones found in the
literature, that were included our multi-frequency scatter time
database, along with the data published earlier in Lewandowski et al.
(2013MNRAS.434...69L 2013MNRAS.434...69L)
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 55 97 List of studied pulsars
tablea1.dat 40 417 Multi frequency scatter time measurements
database
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Simbad right ascension (J2000)
4- 5 I2 min RAm Simbad right ascension (J2000)
7- 11 F5.2 s RAs Simbad right ascension (J2000)
13 A1 --- DE- Simbad declination sign (J2000)
14- 15 I2 deg DEd Simbad declination (J2000)
17- 18 I2 arcmin DEm Simbad declination (J2000)
20- 23 F4.1 arcsec DEs Simbad declination (J2000)
25- 27 A3 --- --- [PSR]
29- 38 A10 --- PSR Pulsar name
42- 55 A14 --- SName Simbad name
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- PSR Pulsar name
12- 18 F7.2 MHz Freq observing frequency (MHZ)
20- 28 F9.5 ms taud Scatter time (taud) in milliseconds
30- 38 F9.5 ms e_taud ?=0 Scatter time uncertainty (1)
39- 40 I2 --- Ref [1/16] Reference (2)
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Note (1): The value of "0" means that no error estimate was present in the
original source (in case of referenced values), or that the error estimate
from our fit was considered unreliable (usually larger than the value of the
scatter time itself).
Note (2): References as follows:
1 = Alurkar, Bobra & Slee (1986AuJPh..39..433A 1986AuJPh..39..433A)
2 = our analysis based on the profiles from the EPN Database
3 = Rickett (1977, ARA&A, 15, 479)
4 = Manchester, D'Amico & Tuohy (1985MNRAS.212..975M 1985MNRAS.212..975M)
5 = Rankin (1981AJ.....86..418R 1981AJ.....86..418R)
6 = Cordes, Weisberg & Boriakoff (1985ApJ...288..221C 1985ApJ...288..221C)
7 = Gullahorn & Rankin (1978AJ.....83.1219G 1978AJ.....83.1219G)
8 = Slee, Dulk & Otrupcek (1980PASAu...4..100S 1980PASAu...4..100S)
9 = Lewandowski et al. (2013MNRAS.434...69L 2013MNRAS.434...69L)
10 = Lohmer et al. (2001ApJ...562L.157L 2001ApJ...562L.157L)
11 = Ables Komesaroff & Hamilton (1970, AstL, 6, 147)
12 = our analysis based on the pulsar profiles from the ATNF Parkes Database
13 = Kuzmin & Losovsky (2007, AAT, 26, 597)
14 = our analysis of new observations performed at GMRT
15 = Staelin & Shutton (1970, Nature, 226, 69)
16 = Ulyanov, Seredkina & Shevtsova (2012, IAUSymp. 291, 527)
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History:
From electronic version of the journal
References:
Lewandowski et al., Paper I 2013MNRAS.434...69L 2013MNRAS.434...69L
(End) Patricia Vannier [CDS] 10-Nov-2015