Erratum: ``Nuclear Accretion in Galaxies of the Local Universe: Clues from Chandra Observations'' (ApJ, 624, 155 [2005])

Details Erratum: ``Nuclear Accretion in Galaxies of the Local Universe: Clues from Chandra Observations'' (ApJ, 624, 155 [2005]) Erratum: ``Nuclear Accretion in Galaxies of the Local Universe: Clues from Chandra Observations'' (ApJ, 624, 155 [2005])

Jan 2006

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006apj...636..564p&link_type=abstract

The Astrophysical Journal, Volume 636, Issue 1, pp. 564-564.

Astronomy and Astrophysics

Astronomy

Errata, Addenda

Scientific paper

Because of an error at the Press, several instances of m˙ in § 3.4 were incorrectly set as M˙, rendering this passage confusing. The correct full text of § 3.4 is given below, with affected passages underlined. The Press sincerely regrets this error.
3.4. Relationship between Eddington-scaled Quantities
Figure 3 shows the relationship between the Eddington-scaled quantities LX,nuc/LEdd and M˙B/M˙Edd (with M˙Edd=LEdd/0.1c2). The reason for plotting Eddington-scaled quantities lies in the possibility of a direct comparison with the predictions of low radiative efficiency advection-dominated accretion flows (ADAFs; Narayan & Yi 1995). These can develop in the conditions of very low m˙ (defined as m˙=M˙/M˙Edd), precisely when m˙<α2<~0.1, where α is a viscosity parameter for the flow. ADAF models predict a rate of mass accretion M˙ comparable to the Bondi rate, with a more accurate estimate that may be M˙~αM˙B (Quataert 2003). Given the values of the abscissae for the points in Figure 3, these nuclei are candidates for hosting ADAFs. In these flows the matter is so hot and tenuous that it is unable to radiate strongly; most of the gravitational potential energy is advected by ions inside the event horizon. The ADAF emission is in the X-ray and in the radio bands2 and scales as LADAF~0.1M˙c2(m˙/α2) (Narayan & Yi 1995). This emission level is plotted as a dashed line in Figure 3 for the two cases of M˙=M˙B and M˙=αM˙B with α=0.1 (a value typically assumed for galactic SMBHs; Di Matteo et al. 2003). Figure 3 shows that LADAF is in fact much lower than Lacc, so an ADAF may explain the emission level for a few nearby galactic nuclei. However, LADAF is still too high for the emission level of many other nuclei. The most discrepant cases are those of the galaxies in the lower right portion of Figure 3-NGC 4472 and NGC 1399 (see also Loewenstein et al. 2001), NGC 4649, and the Galactic center (e.g., Baganoff et al. 2003; Yuan et al. 2003). Note also how the possibility of an ADAF reproducing the observed values of LX,nuc decreases with increasing M˙B/M˙Edd, since LADAF/LEdd increases steeply as m˙2.

Affiliated with

Also associated with

No associations

Rating

Erratum: ``Nuclear Accretion in Galaxies of the Local Universe: Clues from Chandra Observations'' (ApJ, 624, 155 [2005]) does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Erratum: ``Nuclear Accretion in Galaxies of the Local Universe: Clues from Chandra Observations'' (ApJ, 624, 155 [2005]), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Erratum: ``Nuclear Accretion in Galaxies of the Local Universe: Clues from Chandra Observations'' (ApJ, 624, 155 [2005]) will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1284211