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Title: An enigmatic 380 kpc long linear collimated galactic tail
ABSTRACT We present a serendipitously detected system consisting of an S0/a galaxy, which we refer to as the ‘Kite,’ and a highly collimated tail of gas and stars that extends over 380 kpc and contains pockets of star formation. In its length, narrowness, and linearity the Kite’s tail is an extreme example relative to known tails. The Kite (PGC 1000273) has a companion galaxy, Mrk 0926 (PGC 070409), which together comprise a binary galaxy system in which both galaxies host active galactic nuclei. Despite this systems being previously searched for signs of tidal interactions, the tail had not been discovered prior to our identification as part of the validation process of the SMUDGes survey for low surface brightness galaxies. We confirm the kinematic association between various H α knots along the tail, a small galaxy, and the Kite galaxy using optical spectroscopy obtained with the Magellan telescope and measure a velocity gradient along the tail. The Kite shares characteristics common to those formed via ram pressure stripping (‘jellyfish’ galaxies) and formed via tidal interactions. However, both scenarios face significant challenges that we discuss, leaving open the question of how such an extreme tail formed. We propose that the tail resulted from a three-body interaction from which the lowest mass galaxy was ejected at high velocity.  more » « less
Award ID(s):
2006785
PAR ID:
10546331
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Royal Society
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
524
Issue:
1
ISSN:
0035-8711
Page Range / eLocation ID:
1431 to 1437
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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