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Table 1

The sample of external galaxies observed by Chandra.

Galaxy Type Distance N H Study field M ∗ /LK M  ∗  Exp. Sensitivity dx/dy Conversion factor
(Mpc) (1020 cm-2) (M/LK, ⊙ ) (1010 M) (ks) (erg s-1) (pixel) (erg cm-2 count-1)
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11)

M 31 Sab 0.78 ± 0.03 6.7 r = 11′ 0.56 2.7  ~300 4 × 1034 +0.02/−0.37 3.4 × 10-9
15′,9′,−65° 0.60  ~150 7 × 1034 +0.11/+0.51
Cen A S0 3.4 ± 0.4 8.6 r = 10′ 0.76 6.4  ~800 6 × 1035 – /– 3.5 × 10-9
M 81 Sab 3.63 ± 0.34 4.2 10′,5′,−20° 0.70 6.0  ~240 7 × 1035 +0.10/+0.49 3.2 × 10-9
Maffei 1 S0 3.0 ± 0.3 85.1 D25 & HST 0.73 1.1  ~55 3 × 1036 +0.01/+0.29 7.7 × 10-9
N3379 E1 11.1 2.8 D25 & HST 0.83 5.4  ~330 4 × 1036 – /– 3.1 × 10-9
N4697 E6 11.8 2.1 D25 0.77 5.8  ~200 5 × 1036 – /– 3.0 × 10-9
N4278 E1-2 16.1 1.8 D25 & HST 0.79 4.2  ~480 6 × 1036 – /– 3.0 × 10-9

Notes. (1) – Galaxy name. For M 31, the first line is for the bulge region, the second line is for the region in the disk. (2) – Galaxy type. (3) – Distance and its uncertainty (when available). References and methods are: M 31 – luminosity function of red clump stars (Stanek & Garnavich 1998); Centaurus A – Cepheids (Ferrarese et al. 2007); M 81 – Cepheids (Freedman et al. 1994); Maffei 1 – galaxy fundamental plane (Fingerhut et al. 2003); NGC 3379 – luminosity function of GCs (Kundu & Whitmore 2001); NGC 4697, NGC 4278 – surface brightness fluctuation (Tonry et al. 2001). (4) – Galactic column density (Dickey & Lockman 1990). (5) – The region used to study XLFs. When three numbers are given, they refer to major, minor axis and position angle. (6) – K-band mass-to-light ratios derived from Bell & de Jong (2001), with B − V colors from the RC3 catalog (de Vaucouleurs et al. 1991) except for Maffei 1, which is from Buta & McCall (1983). (7) – Stellar mass in the study field, as calculated from the K-band magnitudes derived from 2MASS Large Galaxy Atlas (Jarrett et al. 2003). For M 31 we used the IRAC/Spitzer data, and the 3.6 μm flux was converted to K-band following Bogdán & Gilfanov (2010). (8) – The total exposure time of Chandra observations. (9) – Point source detection sensitivity estimated from the incompleteness functions in Fig. 5. (10) – Attitude correction. (11) – Conversion factor of Chandra count rate to unabsorbed X-ray flux in the 0.5–8 keV band.

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