Discovery of Nuclear X-Ray Sources in Sings Galaxies

Grier, C. J.; Mathur, S.; Ghosh, H.; Ferrarese, Laura

doi:10.1088/0004-637x/731/1/60

Cited by 79 publications

(91 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Rosat, XMM-Newton, Chandra X-ray, and VLA 1.4, 4.86 GHz radio continuum images of NGC 4569 show extended features that are perpendicular to the stellar disc of the galaxy (Tschoeke et al 2001;Chyzy et al 2006;Grier et al 2011;Wezgowiec et al 2011Wezgowiec et al , 2012. The extension of the hot gas traced by the 0.2−1 keV XMM-Newton X-ray image, however, is smaller than that of the ionized gas (Figs.…”

Section: Comparison With Multifrequency Datamentioning

confidence: 99%

Spectacular tails of ionized gas in the Virgo cluster galaxy NGC 4569

Boselli

Cuillandre

Fossati

et al. 2016

A&A

Self Cite

132

169

View full text Add to dashboard Cite

Using MegaCam at the CFHT, we obtained a deep narrow band Hα+ [NII] wide-field image of NGC 4569 (M90), the brightest late-type galaxy in the Virgo cluster. The image reveals the presence of long tails of diffuse ionized gas, without any associated stellar component extending from the disc of the galaxy up to 80 kpc (projected distance) and with a typical surface brightness of a few 10 −18 erg s −1 cm −2 arcsec −2 . These features provide direct evidence that NGC 4569 is undergoing a ram-presure stripping event. The image also shows a prominent 8 kpc spur of ionized gas that is associated with the nucleus that spectroscopic data identify as an outflow. With some assumptions on the 3D distribution of the gas, we use the Hα surface brightness of these extended low-surface brightness features to derive the density and the mass of the gas that has been stripped during the interaction of the galaxy with the intracluster medium. The comparison with ad hoc chemo-spectrophotometric models of galaxy evolution indicates that the mass of the Hα emitting gas in the tail is a large fraction of that of the cold phase that has been stripped from the disc, suggesting that the gas is ionized within the tail during the stripping process. The lack of star-forming regions suggests that mechanisms other than photoionization are responsible for the excitation of the gas (shocks, heat conduction, magneto hydrodynamic waves). This analysis indicates that ram pressure stripping is efficient in massive (M star 10 10.5 M ) galaxies located in intermediate-mass ( 10 14 M ) clusters under formation. It also shows that the mass of gas expelled by the nuclear outflow is only ∼1% than that removed during the ram pressure stripping event. Together these results indicate that ram pressure stripping, rather than starvation through nuclear feedback, can be the dominant mechanism that is responsible for the quenching of the star formation activity of galaxies in high density environments.Key words. galaxies: individual: NGC 4569 -galaxies: clusters: general -galaxies: clusters: individual: Virgo -galaxies: evolutiongalaxies: interactions -galaxies: ISM Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canadian-French-Hawaii Telescope (CFHT) which is operated by the

show abstract

Section: Comparison With Multifrequency Datamentioning

confidence: 99%

Spectacular tails of ionized gas in the Virgo cluster galaxy NGC 4569

Boselli

Cuillandre

Fossati

et al. 2016

A&A

Self Cite

132

169

View full text Add to dashboard Cite

show abstract

“…This provides uniform 5−30 µm spectra in the spectral mapping mode. Most galaxies in the SINGS sample have also been observed with Chandra, and their main X-ray properties are described by Grier et al (2011).…”

Section: Samplementioning

confidence: 99%

“…We have also added NGC 3079, which was not analysed by González-Martín et al (2009a), but it was included as a Compton-thick LINER by Goulding et al (2012). Grier et al (2011) included 20 LINERs (8 included in González-Martín et al 2009a). …”

Section: Samplementioning

confidence: 99%

See 1 more Smart Citation

Nuclear obscuration in LINERs

González‐Martín

Masegosa

Márquez

et al. 2015

A&A

View full text Add to dashboard Cite

Context. Most of the optically classified low-ionisation, narrow emission-line regions (LINERs) nuclei host an active galactic nucleus (AGN). However, how they fit into the unified model (UM) of AGN is still an open question.Aims. The aims of this work are to study at mid-infrared (mid-IR) (1) the Compton-thick nature of LINERs (i.e. hydrogen column densities of N H > 1.5 × 10 24 cm −2 ) and (2) the disappearance of the dusty torus in LINERs predicted from theoretical arguments. Methods. We have compiled all the available low spectral-resolution, mid-IR spectra of LINERs from the InfraRed Spectrograph (IRS) onboard Spitzer. The sample contains 40 LINERs. We have complemented the LINER sample with Spitzer/IRS spectra of PG QSOs, Type-1 Seyferts (S1s), Type-2 Seyferts (S2s), and StarBurst (SB) nuclei. We studied the AGN compared to the starburst content in our sample using different indicators: the equivalent width of the polycyclic aromatic hydrocarbon at 6.2 µm, the strength of the silicate feature at 9.7 µm, and the steepness of the mid-IR spectra. We classified the spectra as SB-dominated and AGN-dominated, according to these diagnostics and compared the average mid-IR spectra of the various classes. Moreover, we studied the correlation between the 12 µm luminosity, νL ν (12 µm), and the 2−10 keV energy band X-ray luminosity, L X (2−10 keV). Results. In 25 out of the 40 LINERs (i.e. 62.5%), the mid-IR spectra are not SB-dominated, similar to the comparison S2 sample (67.7%). The average spectra of both SB-dominated LINERs and S2s are very similar to the average spectrum of the SB class. The average spectrum of AGN-dominated LINERs is different from the average spectra of the other optical classes, showing a rather flat spectrum at 6−28 µm. We find that the average spectrum of AGN-dominated LINERs with X-ray luminosities L X (2−10 keV) > 10 41 erg/s is similar to the average mid-IR spectrum of AGN-dominated S2s. However, faint LINERs (i.e. L X (2−10 keV) < 10 41 erg/s) show flat spectra different from any of the other optical classes. The correlation between νL ν (12 µm) and L X (2−10 keV) for AGN nicely extends towards low luminosities only if SB-dominated LINERs are excluded and if the 2−10 keV band X-ray luminosity is corrected in Compton-thick LINER candidates. Conclusions. We find that LINERs proposed as Compton-thick candidates at X-ray wavelengths may be confirmed according to the X-ray to mid-IR luminosity relation. We show evidence that the dusty-torus disappear when their bolometric luminosity is below L bol 10 42 erg/s. We suggest that the dominant emission at mid-IR of faint LINERs might be a combination of an elliptical galaxy host (characterised by the lack of gas), a starburst, a jet, and/or ADAF emission. Alternatively, the mid-IR emission of some of these faint LINERs could be a combination of elliptical galaxy plus carbon-rich planetary nebulae. To reconcile the Compton-thick nature of a large number of LINERs without dusty-torus signatures, we suggest that the material producing the ...

show abstract

“…Different observations now question that BH-host correlations indeed appear as tight as previously claimed for all types of galaxies (e.g., Hu 2008;Graham 2008;Gültekin et al 2009;Graham & Li 2009). Significant outliers exist (e.g., Mathur et al 2001;Grupe & Mathur 2004;Watson et al 2007), BHs are currently observed also in the centres of bulgeless galaxies (e.g., Ghosh et al 2008;Satyapal et al 2009;Araya salvo et al 2012), and the AGN-starformation correlations disappear for all but highest luminosity AGNs (Shao et al 2010;Grier et al 2011).…”

Section: Introductionmentioning

confidence: 98%

Black holes in pseudobulges: demography and models

Shankar

Marulli

Mathur

et al. 2012

A&A

Self Cite

View full text Add to dashboard Cite

Context. There is mounting evidence that a significant fraction of black holes (BHs) today live in late-type galaxies, including bulgeless galaxies and those hosting pseudobulges, and are significantly undermassive with respect to the scaling relations followed by their counterpart BHs in classical bulges of similar stellar (or even bulge) mass. Aims. Here we discuss the predictions of two state-of-the-art hierarchical galaxy formation models in which BHs grow via mergers and, in one, also via disc instability. Our aim is to understand if the wealth of new data on local BH demography is consistent with standard models. Methods. We follow the merger trees of representative subsamples of BHs and compute the fractional contributions of different processes to the final BH mass. Results. We show that the model in which BHs always closely follow the growth of their host bulges, also during late disk instabilities (i.e., bars), produces too narrow a distribution of BHs at fixed stellar mass to account for the numerous low-mass BHs now detected in later-type galaxies. Models with a looser connection between BH growth and bar instability instead predict the existence of a larger number of undermassive BHs, in better agreement with the observations. Conclusions. The scatter in the updated local BH-bulge mass relation (with no restriction on galaxy type) appears to be quite large when including later-type systems, but it can still be managed to be reproduced within current hierarchical models. However, the fuelling of BHs during the late bar-instability mode needs to be better quantified/improved to properly fit the data. We conclude discussing how the possibly large number of BHs in later type galaxies demands for an in-depth revision of the local BH mass function and its modelling.

show abstract

Discovery of Nuclear X-Ray Sources in Sings Galaxies

Cited by 79 publications

References 72 publications

Spectacular tails of ionized gas in the Virgo cluster galaxy NGC 4569

Spectacular tails of ionized gas in the Virgo cluster galaxy NGC 4569

Nuclear obscuration in LINERs

Black holes in pseudobulges: demography and models

Contact Info

Product

Resources

About