J/ApJ/804/23 327MHz observations of 124 pulsars (Krishnakumar+, 2015)
Scatter broadening measurements of 124 pulsars at 327 MHz.
Krishnakumar M.A., Mitra D., Naidu A., Joshi B.C., Manoharan P.K.
<Astrophys. J., 804, 23 (2015)>
=2015ApJ...804...23K 2015ApJ...804...23K
ADC_Keywords: Pulsars ; Radio continuum
Keywords: ISM: general; pulsars: general; scattering
Abstract:
We present the measurements of scatter broadening timescales
(τSC) for 124 pulsars at 327MHz using the upgraded Ooty Radio
Telescope (ORT). These pulsars lie in the dispersion measure range of
37-503pc/cm3 and declination (δ) range of
-57°<σ<60°. New τSC estimates for 58 pulsars are
presented, increasing the sample of all such measurements by about 40%
at 327MHz. Using all available τSC measurements in the
literature, we investigate the dependence of τSC on dispersion
measure. Our measurements, together with previously reported values
for τSC, affirm that the ionized interstellar medium up to 3kpc
is consistent with the Kolmogorov spectrum, while it deviates
significantly beyond this distance.
Description:
Observations were conducted for 124 pulsars from 2013 January to 2014
September using Ooty Radio Telescope (ORT) - situated in southern
India - at 327MHz.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 56 124 Summary of Observations
table2.dat 93 124 Results
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See also:
VII/189 : Catalog of Pulsars (Taylor+ 1995)
VII/156 : Catalog of 558 Pulsars (Taylor+ 1993)
J/ApJ/763/80 : GBT 350MHz survey. I. 13 new pulsars (Boyles+, 2013)
J/MNRAS/423/1351 : Energy distribution in pulsars (Burke-Spolaor+, 2012)
J/A+A/513/A65 : Rotation measures in the 4th Galactic quadrant (Nota+, 2010)
J/AZh/87/238 : Pulse profile of radio pulsars at 102, 111MHz (Malov+, 2010)
J/MNRAS/391/1210 : Characteristics of energetic pulsars (Weltevrede+, 2008)
J/MNRAS/386/1881 : New pulsar rotation measures (Noutsos+, 2008)
J/AZh/84/685 : Scattering of pulsar radio emission (Kuz'min+, 2007)
J/ApJ/642/868 : Rotation measures for 223 pulsars (Han+, 2006)
J/MNRAS/353/1311 : Long-term timing observations of 374 pulsars (Hobbs+, 2004)
J/MNRAS/352/1439 : Parkes Multi-Beam Pulsar Survey. IV. (Hobbs+, 2004)
J/ApJ/605/759 : Multifrequency obs. of radio pulse broadening (Bhat+, 2004)
J/AJ/128/1646 : The Galactic Center region at 330MHz (Nord+, 2004)
J/AZh/79/501 : Radio luminosities of normal + ms pulsars (Kuz'min, 2002)
J/MNRAS/328/17 : Parkes Multi-Beam Pulsar Survey (Manchester+, 2001)
J/A+AS/147/195 : Pulsar spectra of radio emission (Maron+, 2000)
J/MNRAS/301/235 : Multifrequency polarimetry of 300 pulsars (Gould+, 1998)
J/MNRAS/273/411 : Multifrequency fluxes of 280 pulsars (Lorimer+ 1995)
J/AZh/71/762 : Radio luminosities of 232 pulsars (Malov+, 1994)
http://www.atnf.csiro.au/research/pulsar/psrcat : ATNF pulsar catalogue
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Running sequence number
5- 14 A10 --- PSR Pulsar identifier
16- 23 F8.2 d MJD Modified Julian Day of observation
25- 32 F8.6 s Per [0.03/2.8] Pulsar period
34- 39 F6.2 pc/cm3 DM [37/503] Dispersion measure (G1)
41- 48 F8.2 rad/m2 RM [-1000/978]? Rotation measure (G1)
50- 52 I3 min Exp [7/419] Duration of observation
54- 56 I3 --- SNR [5/519] Peak Signal-to-Noise
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Running sequence number
5 A1 --- f_Seq [b] (ar observed in other places (1)
7- 16 A10 --- PSR Pulsar identifier
18- 19 A2 --- n_PSR [1d *] Peculiar pulsar PSR (2)
21- 26 F6.2 deg GLON Galactic longitude (G1)
28- 34 F7.3 deg GLAT Galactic latitude (G1)
36- 41 F6.2 pc/cm3 DM [37/503] Dispersion measure (G1)
43- 48 F6.2 ms tau [0.1/543] Measured scatter broadening time-scale
(τsc)
50- 55 F6.2 ms e_tau [0.01/184] Uncertainty in tau
57- 63 F7.2 ms W3 [3.9/1113] The 3σ pulse width
65- 67 F3.1 --- chi2 [0.5/2.7] Normalized χ2
69- 72 I4 --- dof [97/1021] Number of degrees of freedom
74- 76 F3.1 kpc D [0.2/9] Distance calculated from
Cordes & Lazio (2002astro.ph..7156C 2002astro.ph..7156C) model
78- 87 F10.5 ms tau1 Expected τsc calculated from
Cordes & Lazio (2002astro.ph..7156C 2002astro.ph..7156C) model
89- 93 F5.2 --- C2 [-3.2/1.3] Scattering strength;
in units of m-20/3
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Note (1):
b = Observed with ORT by Ramachandran et al. (1997MNRAS.290..260R 1997MNRAS.290..260R) and
Mitra & Ramachandran (2001A&A...370..586M 2001A&A...370..586M).
Note (2): Flag as follows:
1 = Since it is a glitching pulsar, the period provided by TEMPO2
predictors can have an offset. Hence the period of the pulsar is found
from several observations with ORT. Since this solution can also have
unknown errors in period, the τsc obtained can have
larger uncertainty.
* = A pulsar for which the pulse broadening function PBF2 from LKMLL01 was
also fitted as discussed in Section 2.2.
d = A pulsar with multicomponent profiles, where only one of the components
is fitted to get an estimate of the τsc, due to the effects of
profile evolution as discussed in Section 2.2.
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Global notes:
Note (G1): cf. ATNF pulsar catalog, Manchester et al. (2005AJ....129.1993M 2005AJ....129.1993M).
http://www.atnf.csiro.au/research/pulsar/psrcat/ .
A blank means no rotation measure available in the literature.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 05-Aug-2015