J/MNRAS/388/1537 Galaxy pairs from SDSS-DR2 (McIntosh+, 2008)
Ongoing assembly of massive galaxies by major merging in large groups and
clusters from the SDSS.
McIntosh D.H., Guo Y., Hertzberg J., Katz N., Mo H.J., Van Den Bosch F.C.,
Yang X.
<Mon. Not. R. Astron. Soc., 388, 1537-1556 (2008)>
=2008MNRAS.388.1537M 2008MNRAS.388.1537M
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Redshifts
Keywords: galaxies: clusters: general - galaxies: evolution -
galaxies: formation - galaxies: interactions
Abstract:
We investigate the incidence of major mergers creating massive
(Mstar>1011M☉) galaxies in present-day (z≤0.12) groups and
clusters. Using a volume-limited sample of 845 groups with dark matter
halo masses above 2.5x1013M☉, we isolate 221 galaxy pairs
with ≤1.5 r-band magnitude differences, ≤30kpc projected
separations and combined masses above 1011M☉. We fit the
r-band images of each pair as the line-of-sight projection of
symmetric models and identify 38 mergers by the presence of residual
asymmetric structure associated with both progenitors, such as
non-concentric isophotes, broad and diffuse tidal tails and dynamical
friction wakes.
Description:
We make use of the SDSS DR2 group catalogue (Weinmann et al.,
2006MNRAS.366....2W 2006MNRAS.366....2W), which was constructed by applying the Yang et
al. (2005MNRAS.356.1293Y 2005MNRAS.356.1293Y) halo-based group finder to the New York
University Value-Added Galaxy Catalogue (NYU-VAGC, Blanton et al.,
2005AJ....129.2562B 2005AJ....129.2562B).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 138 21 Progenitors of massive central merger systems
table3.dat 138 17 Progenitors of massive satellite merger systems
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See also:
http://www.sdss.org : SDSS Home Page
http://sdss.physics.nyu.edu/vagc : NYU-VAGC Home Page
Byte-by-byte Description of file: table2.dat table3.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Group Group identification number,
[MGH2008] Group NNNN
6- 10 F5.2 [solMass] logMass Dark matter halo mass estimate
12- 14 A3 --- gal1 [CEN SAT] First galaxy property (1)
15 A1 --- n_gal1 [+*] Large mass estimate (2)
17- 22 I6 --- NYUID NYU number for first galaxy,
[MGH2008] NYU NNNNNN in Simbad (3)
24- 25 I2 h RAh First galaxy right ascension (J2000)
27- 28 I2 min RAm First galaxy right ascension (J2000)
30- 33 F4.1 s RAs First galaxy right ascension (J2000)
35 A1 --- DE- First galaxy declination sign (J2000)
36- 37 I2 deg DEd First galaxy declination (J2000)
39- 40 I2 arcmin DEm First galaxy declination (J2000)
42- 45 F4.1 arcsec DEs First galaxy declination (J2000)
47- 51 F5.3 --- z ? Spectrosocopic redshift from NYU-VAGC
for first galaxy
53- 57 F5.2 [solMass] logMst Stellar mass estimate for first galaxy
59- 63 F5.2 [solMass] e_logMst rms uncertainty on logMstar
64 A1 --- u_logMst [*] Large uncertainty on logMst (4)
66- 69 F4.2 --- g-r Rest-frame K-corrected to z=0.0 colour from
SDSS Petrosian (Model) photometry
for first galaxy
71- 74 F4.2 --- e_g-r rms uncertainty on g-r
76- 78 A3 --- gal2 [SAT NO] Second galaxy property (1)
79 A1 --- n_gal2 [*+] Large mass estimate (2)
81- 86 I6 --- NYUID2 ? NYU number for second galaxy,
[MGH2008] NYU NNNNNN in Simbad (3)
88- 89 I2 h RA2h Second galaxy right ascension (J2000)
91- 92 I2 min RA2m Second galaxy right ascension (J2000)
94- 97 F4.1 s RA2s Second galaxy right ascension (J2000)
99 A1 --- DE2- Second galaxy declination sign (J2000)
100-101 I2 deg DE2d Second galaxy declination (J2000)
103-104 I2 arcmin DE2m Second galaxy declination (J2000)
106-109 F4.1 arcsec DE2s Second galaxy declination (J2000)
111-115 F5.3 --- z2 ? Spectrosocopic redshift from NYU-VAGC
for second galaxy
117-121 F5.2 [solMass] logMst2 Stellar mass estimate for second galaxy
123-127 F5.2 [solMass] e_logMst2 rms uncertainty on logMst2
128 A1 --- u_logMst2 [*] Large uncertainty on logMst2 (4)
130-133 F4.2 --- g-r2 Rest-frame K-corrected to z=0.0 colour from
SDSS Petrosian (Model) photometry
for second galaxy
135-138 F4.2 --- e_g-r2 rms uncertainty on g-r2
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Note (1): Property is CEN = central galaxy, SAT = satellite galaxy,
and NO = not identified.
Note (2): Note as follows:
+ = Estimated stellar mass of the companion exceeds that of the
spectroscopic CEN galaxy of the host; the merger is added to the
CEN-SAT subset in the analysis
* = Total estimated stellar mass of the two SATs (M1+M2) exceeds that
of the spectroscopic CEN galaxy of the host; including/excluding
the merger to the CEN-SAT subset is analysed
Note (3): Galaxies also identified as [MGH2008] JHHMMSS.s+DDMMSS.s in Simbad.
Note (4): the asterisk (*) indicates that more than factor of 2 difference
(0.3dex) exists between Petrosian and model-based Mst estimates
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 26-Jan-2009