Astronomical Applications Department, U.S. Naval Observatory thesis Page 63
49
7
8
9
10
11
Log M
g
-2
-1
0
1
Log SFR
FUV
Fig. 4.7. Relationship between mass of gas and star formation rate
Galaxy
M
g
SFR
FUV
10
8
M
10
,9
M yr
,1
pc
,2
HoII
9.1
0.45
1.9
IC2574
6.7
0.08
2.2
Sextans A
0.7
0.47
2.2
Table 4.4. Normalized Star Formation Rates and Gas Properties
A more stringent test of the relationship between the SFR and global gas char-
acteristics is made by comparing normalized quantities. Kennicutt 1998 sum-
marizes the results from a variety of studies which characterize the disk-averaged
SFR M yr
,1
pc
,2
and the mean gas surface density,
g
, of galaxies of di erent
morphological types. The surface density of gas is a good indicator of the volume
density; a higher SFR is expected from a higher volume gas density. On average,
