J/MNRAS/484/3691 UTMOST pulsar timing programme. I. (Jankowski+, 2019)
The UTMOST pulsar timing programme I: Overview and first results.
Jankowski F., Bailes M., Van Straten W., Keane E.F., Flynn C., Barr E.D.,
Bateman T., Bhandari S., Caleb M., Campbell-Wilson D., Farah W.,
Green A.J., Hunstead R.W., Jameson A., Oslowski S., Parthasarathy A.,
Rosado P.A., Venkatraman Krishnan V.
<Mon. Not. R. Astron. Soc., 484, 3691-3712 (2019)>
=2019MNRAS.484.3691J 2019MNRAS.484.3691J (SIMBAD/NED BibCode)
ADC_Keywords: Pulsars ; Radio continuum ; Radio sources ; Positional data ;
Ephemerides ; Interferometry ; Models ; Proper motions
Keywords: radiation mechanisms: non-thermal - instrumentation: interferometers -
methods: data analysis - astrometry - ephemerides - pulsars: general
Abstract:
We present an overview and the first results from a large-scale pulsar
timing programme that is part of the UTMOST project at the refurbished
Molonglo Observatory Synthesis Radio Telescope (MOST) near Canberra,
Australia. We currently observe more than 400 mainly bright southern
radio pulsars with up to daily cadences. For 205 (8 in binaries, 4
millisecond pulsars), we publish updated timing models, together with
their flux densities, flux density variability, and pulse widths at
843 MHz, derived from observations spanning between 1.4 and 3 yr. In
comparison with the ATNF pulsar catalogue, we improve the precision of
the rotational and astrometric parameters for 123 pulsars, for 47 by
at least an order of magnitude. The time spans between our
measurements and those in the literature are up to 48 yr, which allow
us to investigate their long-term spin-down history and to estimate
proper motions for 60 pulsars, of which 24 are newly determined and
most are major improvements. The results are consistent with
interferometric measurements from the literature. A model with two
Gaussian components centred at 139 and 463km/s fits the transverse
velocity distribution best. The pulse duty cycle distributions at 50
and 10 per cent maximum are best described by lognormal distributions
with medians of 2.3 and 4.4 per cent, respectively. We discuss two
pulsars that exhibit spin-down rate changes and drifting subpulses.
Finally, we describe the autonomous observing system and the dynamic
scheduler that has increased the observing efficiency by a factor of
2-3 in comparison with static scheduling.
Description:
We present updated astrometric ephemerides and rotational parameters
for 205 radio pulsars, of which 8 are in binary systems, and 197 are
isolated. For 60 of them, we publish inferred proper motions and
transverse velocities, and for all of them, we report band-integrated
flux densities, modulation indices and pulse widths at 50 and 10 per
cent maximum at a frequency of 843 MHz. Our measurements are based on
up to daily observations with time spans of 1.4 to 3yr performed at
the refurbished Molonglo Observatory Synthesis Radio Telescope (MOST),
a radio interferometer located in Australia.
In table 3, we list the pulsar names (J2000), the proper motions in
right ascension and declination, proper motion measurements from the
literature where available, the maximum time spans between position
measurements, the number of positions in the fit, the references for
the literature proper motions, the pulsar distances and their
transverse velocities.
In table B1, we report the pulsar names (J2000), their positions
referenced to the ICRF, their spin frequencies and first temporal
derivatives, the root mean square timing residuals in us and as a
fractions of the pulsar periods, the number of pulse arrival times,
the reduced chi2 and degrees of freedom of the fits, the timing
baselines and a flag whether we corrected the pulse arrival times for
underestimation.
Table B1 shows the results for 8 pulsars in binary systems.
Table B2 reports the results for 197 isolated pulsars, in a format
analogue to the one of table B1.
In table C1, names (J2000), whether they have interpulses, their
band-integrated flux densities at 843MHz, their robust modulation
indices and their pulse widths at 50 and 10 per cent maximum. The
period, position and dispersion measure determination epoch is set to
MJD 57600 for all pulsars. We report all uncertainties at the 1 sigma
level.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 112 60 Proper motions and velocities for 60 pulsars
tableb1.dat 136 8 Rotational parameters for 8 binary systems
tableb2.dat 157 197 Rotational parameters for 197 isolated pulsars
tablec1.dat 46 205 Flux densities and pulse widths for 205 pulsars
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq [1/60] Running number
4- 13 A10 --- PSRJ Pulsar name (J2000)
15 A1 --- Note [dt] Note (1)
17- 22 F6.2 mas/yr pmRA Proper motion in right ascension
24- 28 F5.2 mas/yr e_pmRA Uncertainty of proper motion in RA
30- 35 F6.2 mas/yr pmDE Proper motion in declination
37- 41 F5.2 mas/yr e_pmDE Uncertainty of proper motion in Dec
43- 49 F7.3 mas/yr pmRAl ? Literature value for proper motion in RA
51- 56 F6.3 mas/yr e_pmRAl ? Uncertainty of lit value of pm in RA
57 A1 --- n_pmRAl [e] Footnote (1)
59- 66 F8.3 mas/yr pmDEl ? Literature value of proper motion in Dec
68- 74 F7.3 mas/yr e_pmDEl ? Uncertainty of lit value of pm in Dec
75 A1 --- n_pmDEl [e] Footnote (1)
77- 80 F4.1 yr dt Maximum time span between pos measurements
82 I1 --- Npos Number of positions in pm estimate
84- 85 I2 --- r_pmRAl [1/15]? Reference for literature
proper motions (2)
87- 92 F6.4 kpc Dist Distance
94- 99 F6.4 kpc e_Dist ? Uncertainty of distance
101-106 F6.1 km/s vtrans Transverse velocity
108-112 F5.1 km/s e_vtrans Uncertainty of transverse velocity
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Note (1): Note as follows:
d = See text
t = Significant proper motion signature in UTMOST timing residuals
e = Literature proper motion was converted from ecliptic to
equatorial coordinates
Note (2): References as follows:
1 = Hobbs et al., 2005MNRAS.360..974H 2005MNRAS.360..974H
2 = Brisken et al., 2003AJ....126.3090B 2003AJ....126.3090B
3 = Siegman et al., 1993MNRAS.262..449S 1993MNRAS.262..449S
4 = Reardon et al., 2016MNRAS.455.1751R 2016MNRAS.455.1751R
5 = Chatterjee et al., 2009ApJ...698..250C 2009ApJ...698..250C
6 = Harrison Lyne and Anderson, 1993MNRAS.261..113H 1993MNRAS.261..113H
7 = Deller et al., 2009ApJ...701.1243D 2009ApJ...701.1243D
8 = Brisken et al., 2002ApJ...571..906B 2002ApJ...571..906B
9 = Mignani Pavlov and Kargaltsev, 2010ApJ...720.1635M 2010ApJ...720.1635M
10 = Bailes et al., 1990MNRAS.247..322B 1990MNRAS.247..322B
11 = Fomalont et al., 1997MNRAS.286...81F 1997MNRAS.286...81F
12 = Zou et al., 2005MNRAS.362.1189Z 2005MNRAS.362.1189Z
13 = Fomalont et al., 1999AJ....117.3025F 1999AJ....117.3025F
14 = Chatterjee et al., 2004ApJ...604..339C 2004ApJ...604..339C
15 = Deller et al., 2013ApJ...770..145D 2013ApJ...770..145D
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1 I1 --- Seq [1/8] Running number
3- 13 A11 --- PSRJ Pulsar name (J2000)
15- 16 I2 h RAh Right ascension (ICRF)
18- 19 I2 min RAm Right ascension (ICRF)
21- 28 F8.5 s RAs Right ascension (ICRF)
30- 36 F7.5 s e_RAs Uncertainty of right ascension
38 A1 --- DE- Declination sign (ICFR)
39- 40 I2 deg DEd Declination (ICRF)
42- 43 I2 arcmin DEm Declination (ICRF)
45- 51 F7.4 arcsec DEs Declination (ICRF)
53- 58 F6.4 arcsec e_DEs Uncertainty of declination
60- 75 F16.12 Hz F0 Pulsar spin frequency
77- 90 F14.12 Hz e_F0 Uncertainty of spin frequency
92-101 F10.4 10-15/s2 F1 First temporal derivative of spin frequency
103-108 F6.4 10-15/s2 e_F1 Uncertainty of first spin frequency
derivative
110-114 F5.1 us RMS Root mean square timing residual
116-118 F3.1 --- RMS/P0 RMS timing residual divided by spin period
120-122 I3 --- NTOA Number of pulse arrival times in fit
124-126 F3.1 --- chi2r Reduced chi2 of the timing fit
128-130 I3 --- dof Degrees of freedom of the timing fit
132-134 F3.1 yr dt Time span of pulse arrival times in fit
136 A1 --- flag [w] Pulse arrival time correction flag (1)
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Note (1): w = ToAs are corrected for underestimation
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Byte-by-byte Description of file: tableb2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Running number
5- 14 A10 --- PSRJ Pulsar name (J2000)
16- 17 I2 h RAh Right ascension (ICRF)
19- 20 I2 min RAm Right ascension (ICRF)
22- 28 F7.4 s RAs Right ascension (ICRF)
30- 35 F6.4 s e_RAs Uncertainty of right ascension
37 A1 --- DE- Declination sign (ICRF)
38- 39 I2 deg DEd Declination (ICRF)
41- 42 I2 arcmin DEm Declination (ICRF)
44- 49 F6.3 arcsec DEs Declination (ICRF)
51- 55 F5.3 arcsec e_DEs Uncertainty of declination
57- 72 F16.12 Hz F0 Pulsar spin frequency
74- 87 F14.12 Hz e_F0 Uncertainty of spin frequency
89- 99 F11.5 10-15/s2 F1 First temp derivative of spin frequency
101-107 F7.5 10-15/s2 e_F1 Uncertainty of first spin freq derivative
108-118 F11.5 10-24/s3 F2 ?=- Second temp derivative of spin frequency
120-126 F7.5 10-24/s3 e_F2 ?=- Uncertainty of second spin frequency
derivative
128-133 F6.1 us RMS Root mean square timing residual
136-139 F4.1 --- RMS/P0 RMS timing residual divided by spin period
141-143 I3 --- NTOA Number of pulse arrival times in fit
145-148 F4.1 --- chi2r Reduced chi2 of the timing fit
150 A1 --- l_chi2r Limit flag on reduced chi2
151-153 I3 --- dof Degrees of freedom of the timing fit
155-157 F3.1 yr dt Time span of pulse arrival times in fit
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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- 3 I3 --- Seq [1/205] Running number
5- 15 A11 --- PSRJ Pulsar name (J2000)
17 A1 --- Note [Y] Label of whether pulsar has an interpulse
19- 24 F6.1 mJy S843 Flux density at 843 MHz
26- 29 F4.1 mJy e_S843 Uncertainty of flux density at 843 MHz
31- 34 F4.2 --- mr Robust modulation index at 843 MHz
36- 40 F5.1 deg W50 ? Full pulse width at 50 per cent maximum
42- 46 F5.1 deg W10 Full pulse width at 10 per cent maximum
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Acknowledgements:
Fabian Jankowski, fjankowsk at gmail.com
(End) F. Jankowski [Univ. of Manchester, UK], P. Vannier [CDS] 04-Feb-2020