J/MNRAS/496/2836 Faraday rotation of Northern hemisphere pulsars (Ng+, 2020)
Faraday rotation measures of Northern hemisphere pulsars using CHIME/Pulsar.
Ng C., Pandhi A., Naidu A., Fonseca E., Kaspi V.M., Masui K.W.,
Mckinven R., Renard A., Scholz P., Stairs I.H., Tendulkar S.P.,
Vanderlinde K.
<Mon. Not. R. Astron. Soc., 496, 2836-2848 (2020)>
=2020MNRAS.496.2836N 2020MNRAS.496.2836N (SIMBAD/NED BibCode)
ADC_Keywords: Pulsars ; Magnetic fields ; Polarization ; Spectra, radio
Keywords: techniques: polarimetric - pulsars: general - ISM: magnetic fields
Abstract:
Using commissioning data from the first year of operation of the
Canadian Hydrogen Intensity Mapping Experiment's (CHIME) Pulsar
backend system, we conduct a systematic analysis of the Faraday
Rotation Measure (RM) of the Northern hemisphere pulsars detected by
CHIME. We present 55 new RMs as well as obtain improved RM
uncertainties for 25 further pulsars. CHIME's low observing frequency
and wide bandwidth between 400 and 800MHz contribute to the precision
of our measurements, whereas the high cadence observation provides
extremely high signal-to-noise co-added data. Our results represent a
significant increase of the pulsar RM census, particularly regarding
the Northern hemisphere. These new RMs are for sources that are
located in the Galactic plane out to 10kpc, as well as off the plane
to a scale height of ∼16kpc. This improved knowledge of the Faraday
sky will contribute to future Galactic large-scale magnetic structure
and ionosphere modelling.
Description:
CHIME is a radio telescope hosted by the Dominion Radio Astrophysical
Observatory (DRAO) in British Columbia, Canada. CHIME operates across
a wide bandwidth of 400-800MHz and has a collecting area (∼80x100m2)
and point-source sensitivity comparable to that of other 100-m class
radio telescopes. The reflecting surface of CHIME consists of four
parabolic cylinders. It is a transit telescope with no moving parts.
For the CHIME/Pulsar project, we combine the signals from the 1024
dual polarization feeds and form 10 tied-array beams that are
available as raw voltages (Ng 2018IAUS..337..179N 2018IAUS..337..179N). This means that we
can track 10 different pulsars at any given time as they transit
through CHIME's field of view, along the meridian. This provides very
high-cadence scheduling: while many of the Northern hemisphere pulsars
are being monitored daily, the longest cadence to cycle through all
sources in the northern sky is only ∼10d. This is reflected in the
long co-added integration length of our data (Totalfold) and the
high signal to noise (S/N) achieved as listed in Table A1. The transit
time of each source is a function of the declination; transit times
can range from tens of minutes to hours for circumpolar sources. CHIME
can in principle observe down to a declination of -20°.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 92 80 Summary of 80 co-added RMs obtained in this work
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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 --- Name Pulsar name (JHHMM+DDMM or BHHMM+DD)
12- 17 F6.2 rad/m2 RM ? Faraday Rotation Measure from literature
19- 23 F5.2 rad/m2 e_RM ? Error on RM
25- 30 A6 --- r_RM Reference for RM (1)
32- 42 A11 d MJD Modified Julian date range
44- 47 F4.1 h tfold Total length of fold mode observation
49- 52 I4 --- S/N Signal to noise ratio of the co-added
profile
54- 61 F8.4 pc/cm3 DMobs Dispersion measure from the co-added data
63- 68 F6.4 pc/cm3 e_DMobs Error on DMobs
70- 75 F6.1 rad/m2 RMobs Faraday Rotation Measure from the co-added
data
77- 79 F3.1 rad/m2 e_RMobs Error on RMobs
81- 86 F6.3 10-6gauss BLOS Line of sight parallel magnetic field
strength
88- 92 F5.3 10-6gauss e_BLOS Error on BLOS
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Note (1): Reference as follows:
bfrs18 = Brinkman et al. (2018MNRAS.474.2012B 2018MNRAS.474.2012B)
gmd+18 = Gentile et al. (2018ApJ...862...47G 2018ApJ...862...47G)
hl87 = Hamilton & Lyne (1987MNRAS.224.1073H 1987MNRAS.224.1073H)
hmvd18 = Han et al. (2018ApJS..234...11H 2018ApJS..234...11H, Cat. J/ApJS/234/11)
hr10 = Hankins & Rankin (2010AJ....139..168H 2010AJ....139..168H)
mwkj03 = Mitra et al. (2003A&A...398..993M 2003A&A...398..993M)
rl94 = Rand & Lyne (1994MNRAS.268..497R 1994MNRAS.268..497R)
sbg+19 = Sobey et al. (2019MNRAS.484.3646S 2019MNRAS.484.3646S, Cat. J/MNRAS/484/3646)
tpc+11 = Theureau et al. (2011A&A...525A..94T 2011A&A...525A..94T)
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 03-Jul-2023