J/ApJ/852/47 "X-shaped" radio sources. I. VLA imaging (Roberts+, 2018)
What are "X-shaped" radio sources telling us?
I. Very Large Array imaging of a large sample of candidate XRGs.
Roberts D.H., Saripalli L., Wang K.X., Rao M.S., Subrahmanyan R.,
KleinStern C.C., Morii-Sciolla C.Y., Simpson L.
<Astrophys. J., 852, 47 (2018)>
=2018ApJ...852...47R 2018ApJ...852...47R
ADC_Keywords: Galaxies, radio ; Redshifts ; Radio continuum ; Morphology
Keywords: galaxies: active ; galaxies: nuclei ; radio continuum: galaxies
Abstract:
We present archival and Jansky Very Large Array multi-frequency
multi-array radio continuum imaging of a unique sample of 100 radio
sources that have been selected to be candidate "X-shaped" radio
galaxies (XRGs). The archival data were calibrated in AIPS (Bridle &
Greisen 1994, NRAO AIPS Memo 87) and imaged using DIFMAP (Shepherd+
1994BAAS...26..987S 1994BAAS...26..987S), while the new Very Large Array data were
calibrated and imaged in CASA (McMullin+ 2007ASPC..376..127M 2007ASPC..376..127M). No
attempt was made to re-image the archival data in CASA. Altogether we
present images of 95 of the 100 sources. These observations give us
the opportunity to study radio sources with synchrotron plasma that is
significantly offset from the main radio axis and therefore to open a
window into investigations of physical mechanisms responsible for
depositing the plasma in off-axis regions. Here, we present the
technical details of the observations and all of the total intensity
images, while in subsequent papers we use them to examine critically
various models for the formation of XRGs. Spectral index and linear
polarization information is also presented and analyzed in further
papers in this series.
Description:
We observed 89 of the 100 sources in the Cheung (2007, J/AJ/133/2097)
sample of candidate "X-shaped" radio galaxies (XRGs) from 2016
February 4 through 2017 January 10 using the VLA at L (1.4GHz) and S
bands (3GHz).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 43 100 The Cheung (2007, J/AJ/133/2097) sample of X-shaped
radio source candidates
table2.dat 86 100 Log of Very Large Array observations of the
Cheung sample of candidate XRGs
table4.dat 126 95 Figure 2 data
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See also:
J/AJ/133/2097 : FIRST "Winged" and X-shaped radio source cand. (Cheung, 2007)
J/ApJS/181/548 : X-shaped radio sources cand. II. New redshifts (Cheung+, 2009)
J/ApJS/220/7 : X-shaped radio source abundances. I. VLA (Roberts+, 2015)
J/ApJ/852/48 : X-shaped radio sources. II. Sample data (Saripalli+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- [C2007] Source, IAU Name (JHHMM+DDMM) (G1)
12- 13 I2 h RAh Hour of Right Ascension (J2000)
15- 16 I2 min RAm Minute of Right Ascension (J2000)
18- 21 F4.1 s RAs Second of Right Ascension (J2000)
23- 23 A1 --- DE- Sign of the Declination (J2000)
24- 25 I2 deg DEd Degree of Declination (J2000)
27- 28 I2 arcmin DEm Arcminute of Declination (J2000)
30- 33 F4.1 arcsec DEs Arcsecond of Declination (J2000)
35- 40 F6.4 --- z [0.03/0.9]? Redshift (1)
42- 43 A2 --- f_z Flag on redshift (2)
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Note (1): Redshifts are largely from SDSS DR-12, with the remaining ones
from Cheung (2007, J/AJ/133/2097), Cheung+ (2009, J/ApJS/181/548),
and Landt+ (2010MNRAS.408.1103L 2010MNRAS.408.1103L).
Note (2): Flag as follows:
S = photometric redshifts from SDSS DR-12;
NA = no redshift information is available.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- [C2007] Source, IAU Name (JHHMM+DDMM) (G1)
12- 19 A8 --- Archival Archival Band/Array data (G2)
21- 86 A66 --- JVLA JVLA Band/Array, YYYY-MM-DD obs
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- [C2007] Source, IAU name (JHHMM+DDMM) (G1)
12- 35 A24 --- Fig2 Element number(s) in Figure 2 (VLA image)
37- 40 F4.2 mJy/beam FA1.4Lc [0.07/0.7]? A-Array L-band (∼1.4GHz),
Lowest contour (G2)
42- 47 F6.2 mJy/beam FA1.4Pk [0.8/178]? A-Array L-band (∼1.4GHz),
Peak intensity (G2)
49- 52 F4.2 mJy/beam FB5Lc [0.08/0.5]? B-Array C-band (∼5GHz),
Lowest contour (G2)
54- 58 F5.1 mJy/beam FB5Pk [10/113]? B-Array C-band (∼5GHz),
Peak intensity (G2)
60- 63 F4.2 mJy/beam FAB3Lc [0.04/0.1]? AB-Array S-band (∼3GHz),
Lowest contour
65- 69 F5.2 mJy/beam FAB3Pk [2/23.4]? AB-Array S-band (∼3GHz), Peak intensity
71- 74 F4.2 mJy/beam FB1.4LC [0.1/0.5]? B-Array L-band (∼1.4GHz),
Lowest contour
76- 81 F6.2 mJy/beam FB1.4Pk [6.8/586]? B-Array L-band (∼1.4GHz),
Peak intensity
83- 86 F4.2 mJy/beam FB3Lc [0.05/0.3]? B-Array S-band (∼3GHz),
Lowest contour
88- 93 F6.2 mJy/beam FB3Pk [1/160]? B-Array S-band (∼3GHz), Peak intensity
95- 98 F4.2 mJy/beam FC3Lc [0.06/0.4]? C-Array S-band (∼3GHz),
Lowest contour
100-105 F6.2 mJy/beam FC3Pk [5.8/335]? C-Array S-band (∼3GHz), Peak intensity
107-116 A10 --- Source2 Source, IAU name (G1) ????
118-126 A9 --- Fig3 Element number(s) in Figure 3 (optical overlay);
column added by CDS (1)
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Note (1): The overlays are made with the one image of each source that we judged
to have the best combination of dynamic range and angular resolution
to relate the radio and optical structures. The overlays were mostly
derived from SDSS DR-12 r-band images, and in the nine cases where
these were unavailable, from the USNO Image and Catalog Archive
Server (http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/icas).
See section 4.
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Global notes:
Note (G1): XRG candidates from the Cheung (2007, J/AJ/133/2097) sample.
Note (G2): Archival data from Roberts et al. (2015ApJS..220....7C 2015ApJS..220....7C)
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History:
From electronic version of the journal
References:
Roberts et al. Paper I. 2018ApJ...852...47R 2018ApJ...852...47R This Catalog
Saripalli et al. Paper II. 2018ApJ...852...48S 2018ApJ...852...48S Cat. J/ApJ/852/48
(End) Prepared by [AAS], Emmanuelle Perret [CDs] 23-Jul-2018