J/other/NewA/11.293 Warped disks in spiral galaxies (Ann+, 2006)
Warped disks in spiral galaxies.
Ann H.B., Park J.-C.
<New Astronomy, 11, 293-305 (2006)>
=2006NewA...11..293A 2006NewA...11..293A
ADC_Keywords: Galaxy catalogs ; Morphology
Keywords: galaxies: morphology - galaxies: photometry - galaxies: structure
Abstract:
We have analyzed the disk morphologies of 325 edge-on galaxies to
derive the warp statistics in spiral galaxies using Digital Sky
Survey. Galaxies were included in our study if their isophotal
diameter (D25) satisfied logD25>1, and if their major-to-minor axis
ratio was in the range a/b>9.5. We found that 236 out of the 325
sample galaxies (73%) had warps: 165 S-shaped (51%) and 71 U-shaped
(22%). We additionally found that the warp properties (warp angles,
warp radius, and warp asymmetry) as well as the warp frequency did not
depend on galaxy morphology. A quite tight anticorrelation was
observed between warp radius and warp amplitude, and a positive
correlation was found between warp asymmetry and warp amplitude. A
detailed analysis of the relations between warp parameters and galaxy
properties revealed that strong warps are mostly caused by tidal
interactions, whereas weak warps are formed by a variety of mechanisms
including gas accretion. The present results indicate that the
fractional warp radius coupled with warp angles representing the warp
amplitude and warp curvature provide useful diagnostic indicators of
the origin of warps.
Description:
We obtained isophotal maps of the selected galaxies using the digital
sky survey. We used the POSSII-blue survey and SERC-J survey.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 62 104 Warp parameters and basic properties of 104
selected galaxies
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See also:
VII/237 : HYPERLEDA. I. Catalog of galaxies (Paturel+, 2003)
J/A+A/382/513 : Galaxy warps in the HDF North and South (Reshetnikov+, 2002)
J/A+A/391/519 : Warps of galaxies (Castro-Rodriguez+, 2002)
J/A+A/399/457 : Warps in southern hemisphere galaxies (Sanchez-Saavedra+ 2003)
J/ApJS/140/265 : WARPS survey. VI. (Perlman+, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [PGC]
5- 9 I5 --- PGC PGC number
12- 19 F8.5 h RAhour Right ascension in decimal hours (J2000)
21- 28 F8.4 deg DEdeg Declination in decimal degrees (J2000)
30- 33 F4.1 --- TType Morphological type
35- 38 F4.2 [arcmin] logD25 Major-axis length of the isophote at
µB=25mag/arcsec2
40 A1 --- Warp [US] (U)-shaped or (S)-shaped
42- 45 F4.1 --- alphaE East side of the disk warp angle alpha (1)
47- 50 F4.1 --- alphaW West side of the disk warp angle alpha (1)
52- 53 I2 --- betaE East side of the disk warp angle beta (2)
55- 56 I2 --- betaW West side of the disk warp angle beta (2)
58- 60 F3.1 --- rw/Ropt Warp-to-optical radius ratio
62 A1 --- C [sc-] Companionship of host galaxies flag (3)
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Note (1): alpha is the angle between the disk major axis and the line
connecting the galaxy center and the tip of the outermost isophotes,
and represents the warp amplitude.
Note (2): beta is the angle between the disk major axis and the line from
the warp radius (rw) to the tip of the outermost isophotes, and
represents the curvature of the warped disk.
Note (3): Companionship of host galaxies flag as follows:
s = companionship from SDSS
c = companionship from NED
- = unknown companionship
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 24-Oct-2006