We present the survey strategy and early results of the "Satellites Around
Galactic Analogs" (SAGA) Survey. The SAGA Survey's goal is to measure the
distribution of satellite galaxies around 100 systems analogous to the Milky
Way down to the luminosity of the Leo I dwarf galaxy ($M_r<-12.3$). We define a
Milky Way analog based on $K$-band luminosity and local environment. Here, we
present satellite luminosity functions for 8 Milky Way analog galaxies between
20 to 40 Mpc. These systems have nearly complete spectroscopic coverage of
candidate satellites within the projected host virial radius down to
$r_o<20.75$ using low redshift $gri$ color criteria. We have discovered a total
of 25 new satellite galaxies. This includes 14 satellite galaxies meeting our
formal criteria around our complete host systems, and an additional 11 in
incompletely surveyed hosts or below our formal magnitude limit. Combined with
13 known satellites, there are a total of 27 satellites around 8 complete Milky
Way analog hosts. We find a wide distribution in the number of satellites per
host, from 1 to 9, in the luminosity range for which there are five Milky Way
satellites. Standard abundance matching extrapolated from higher luminosities
predicts less scatter between hosts and a steeper luminosity function slope
than observed. Unlike the Milky Way satellites, we find that the majority of
satellites (26 of 27) are star-forming. These early results indicate that the
Milky Way has a different satellite population than typical in our sample,
potentially changing the physical interpretation of measurements based only on
the Milky Way's satellite galaxies.
Beschreibung
[1705.06743] The SAGA Survey: I. Satellite Galaxy Populations Around Eight Milky Way Analogs
%0 Generic
%1 geha2017survey
%A Geha, Marla
%A Wechsler, Risa H.
%A Mao, Yao-Yuan
%A Tollerud, Erik J.
%A Weiner, Benjamin
%A Bernstein, Rebecca
%A Hoyle, Ben
%A Marchi, Sebastian
%A Marshall, Phil J.
%A Munoz, Ricardo
%A Lu, Yu
%D 2017
%K forming milky satellite star way
%T The SAGA Survey: I. Satellite Galaxy Populations Around Eight Milky Way
Analogs
%U http://arxiv.org/abs/1705.06743
%X We present the survey strategy and early results of the "Satellites Around
Galactic Analogs" (SAGA) Survey. The SAGA Survey's goal is to measure the
distribution of satellite galaxies around 100 systems analogous to the Milky
Way down to the luminosity of the Leo I dwarf galaxy ($M_r<-12.3$). We define a
Milky Way analog based on $K$-band luminosity and local environment. Here, we
present satellite luminosity functions for 8 Milky Way analog galaxies between
20 to 40 Mpc. These systems have nearly complete spectroscopic coverage of
candidate satellites within the projected host virial radius down to
$r_o<20.75$ using low redshift $gri$ color criteria. We have discovered a total
of 25 new satellite galaxies. This includes 14 satellite galaxies meeting our
formal criteria around our complete host systems, and an additional 11 in
incompletely surveyed hosts or below our formal magnitude limit. Combined with
13 known satellites, there are a total of 27 satellites around 8 complete Milky
Way analog hosts. We find a wide distribution in the number of satellites per
host, from 1 to 9, in the luminosity range for which there are five Milky Way
satellites. Standard abundance matching extrapolated from higher luminosities
predicts less scatter between hosts and a steeper luminosity function slope
than observed. Unlike the Milky Way satellites, we find that the majority of
satellites (26 of 27) are star-forming. These early results indicate that the
Milky Way has a different satellite population than typical in our sample,
potentially changing the physical interpretation of measurements based only on
the Milky Way's satellite galaxies.
@misc{geha2017survey,
abstract = {We present the survey strategy and early results of the "Satellites Around
Galactic Analogs" (SAGA) Survey. The SAGA Survey's goal is to measure the
distribution of satellite galaxies around 100 systems analogous to the Milky
Way down to the luminosity of the Leo I dwarf galaxy ($M_r<-12.3$). We define a
Milky Way analog based on $K$-band luminosity and local environment. Here, we
present satellite luminosity functions for 8 Milky Way analog galaxies between
20 to 40 Mpc. These systems have nearly complete spectroscopic coverage of
candidate satellites within the projected host virial radius down to
$r_o<20.75$ using low redshift $gri$ color criteria. We have discovered a total
of 25 new satellite galaxies. This includes 14 satellite galaxies meeting our
formal criteria around our complete host systems, and an additional 11 in
incompletely surveyed hosts or below our formal magnitude limit. Combined with
13 known satellites, there are a total of 27 satellites around 8 complete Milky
Way analog hosts. We find a wide distribution in the number of satellites per
host, from 1 to 9, in the luminosity range for which there are five Milky Way
satellites. Standard abundance matching extrapolated from higher luminosities
predicts less scatter between hosts and a steeper luminosity function slope
than observed. Unlike the Milky Way satellites, we find that the majority of
satellites (26 of 27) are star-forming. These early results indicate that the
Milky Way has a different satellite population than typical in our sample,
potentially changing the physical interpretation of measurements based only on
the Milky Way's satellite galaxies.},
added-at = {2017-05-22T10:49:18.000+0200},
author = {Geha, Marla and Wechsler, Risa H. and Mao, Yao-Yuan and Tollerud, Erik J. and Weiner, Benjamin and Bernstein, Rebecca and Hoyle, Ben and Marchi, Sebastian and Marshall, Phil J. and Munoz, Ricardo and Lu, Yu},
biburl = {https://www.bibsonomy.org/bibtex/282aca1a703bda59d6170b64a872f3138/miki},
description = {[1705.06743] The SAGA Survey: I. Satellite Galaxy Populations Around Eight Milky Way Analogs},
interhash = {f433103038d2c856f69fb57e1782ad0b},
intrahash = {82aca1a703bda59d6170b64a872f3138},
keywords = {forming milky satellite star way},
note = {cite arxiv:1705.06743Comment: 22 pages, 19 figures, 2 tables. Survey website: http://sagasurvey.org/},
timestamp = {2017-05-22T10:49:18.000+0200},
title = {The SAGA Survey: I. Satellite Galaxy Populations Around Eight Milky Way
Analogs},
url = {http://arxiv.org/abs/1705.06743},
year = 2017
}