ترغب بنشر مسار تعليمي؟ اضغط هنا

A new powerful and highly variable disk wind in an AGN-star forming galaxy, the case of MCG-03-58-007

342   0   0.0 ( 0 )
 نشر من قبل Valentina Braito
 تاريخ النشر 2018
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

We present the discovery of a new candidate for a fast disk wind, in the nearby Seyfert 2 galaxy MCG-03-58-007. This wind is discovered in a deep Suzaku observation that was performed in 2010. Overall the X-ray spectrum of MCG-03-58-007 is highly absorbed by a neutral column density of NH~10^23 cm^-2, in agreement with the optical classification as a type 2 AGN. In addition, this observation unveiled the presence of two deep absorption troughs at E = 7.4 +- 0.1 keV and E = 8.5 +- 0.2 keV. If associated with blue-shifted FeXXVI, these features can be explained with the presence of two highly ionised (log xi/(erg cm/s)~ 5.5) and high column density (NH~5-8 x 10^23cm^-2) outflowing absorbers with v_out1~ -0.1c and v_out2~ -0.2c. The disk wind detected during this observation is most likely launched from within a few hundreds gravitational radii from the central black and has a kinetic output that matches the prescription for significant feedback. The presence of the lower velocity component of the disk wind is independently confirmed by the analysis of a follow-up XMM-Newton & NuSTAR observation. A faster (v_out~ -0.35 c) component of the wind is also seen in this second observation. During this observation we also witnessed an occultation event lasting Delta t ~ 120 ksec, which we ascribe to an increase of the opacity of the disk wind (Delta NH~1.4x10^24 cm^-2). Our interpretation is that the slow zone (v_out~ -0.1c) of the wind is the most stable but inhomogeneous component, while the faster zones could be associated with two different inner streamlines of the wind.



قيم البحث

اقرأ أيضاً

Past Suzaku, XMM and NuSTAR observations of the nearby (z=0.0323) bright Seyfert 2 galaxy MCG-03-58-007 revealed the presence of two deep and blue-shifted Fe K-shell absorption line profiles. These could be explained with the presence of two phases o f a highly ionized, high column density accretion disk wind outflowing with $v_{out1}sim -0.1c$ and $v_{out2}sim -0.2c$. Here we present two new observations of MCG-03-58-007: one was carried out in 2016 with Chandra and one in 2018 with Swift. Both caught MCG-03-58-007 in a brighter state ($F_{mathrm{2-10,keV}}sim 4times 10^{-12}$ erg cm$^{-2}$ s$^{-1}$) confirming the presence of the fast disk wind. The multi-epoch observations of MCG-03-58-007 covering the period from 2010 to 2018 were then analysed. These data show that the lower velocity component outflowing with $v_{out1}sim -0.072pm 0.002c$ is persistent and detected in all the observations, although it is variable in column density in the range $N_rm{H}sim 3-8 times 10^{23}$cm$^{-2}$. In the 2016 Swift observation we detected again the second faster component outflowing with $v_{out2}sim -0.2c$, with a column density ($N_rm{H}=7.0^{+5.6}_{-4.1}times 10^{23}$cm$^{-2}$), similar to that seen during the Suzaku observation. However during the Chandra observation two years earlier, this zone was not present ($N_rm{H}<1.5times 10^{23}$cm$^{-2}$), suggesting that this faster zone is intermittent. Overall the multi-epochs observations show that the disk wind in MCG-03-58-007 is not only powerful, but also extremely variable, hence placing MCG-03-58-007 among unique disk winds such as the one seen in the famous QSO PDS456. One of the main results of this investigation is the consideration that these winds could be extremely variable, sometime appearing and sometime disappearing; thus to reach solid and firm conclusions about their energetics multiple observations are mandatory.
We report the results of a detailed analysis of a deep simultaneous $130,rm ks$ textit{XMM-Newton & NuSTAR} observation of the nearby ($z=0.0315$) and bright ($L_{rm bol}sim3times10^{45},rm erg,s^{-1}$) starburst-AGN Seyfert,2 system: MCG--03--58--00 7. From the broadband fitting we show that most of the obscuration needs to be modeled with a toroidal type reprocessor such as texttt{MYTorus} citep{MurphyYaqoob09}. Nonetheless the signature of a powerful disc-wind is still apparent at higher energies and the observed rapid short-term X-ray spectral variability is more likely caused by a variable zone of highly ionized fast wind rather than by a neutral clumpy medium. We also detect X-ray emission from larger scale gas as seen from the presence of several soft narrow emission lines in the RGS, originating from a contribution of a weak star forming activity together with a dominant photoionized component from the AGN.
We report the first Atacama large millimeter/submillimeter array observations of MCG-03-58-007, a local ($z=0.03236pm0.00002$, this work) AGN ($L_{AGN}sim10^{45}~rm erg~s^{-1}$), hosting a powerful X-ray ultra-fast ($v=0.1c$) outflow (UFO). The CO(1- 0) line emission is observed across $sim18,$kpc scales with a resolution of $sim 1,rm kpc$. About 78% of the CO(1-0) luminosity traces a galaxy-size rotating disk. However, after subtracting the emission due to such rotating disk, we detect with a S/N=20 a residual emission in the central $sim 4,$kpc. Such residuals may trace a low velocity ($v_{LOS}=170,rm km,s^{-1}$) outflow. We compare the momentum rate and kinetic power of such putative molecular outflow with that of the X-ray UFO and find $dot{P}_{out}/dot{P}_{UFO}=0.3pm0.2$ and $dot{E}_{mol}/dot{E}_{UFO}sim4cdot10^{-3}$. This result is at odds with the energy-conserving scenario suggested by the large momentum boosts measured in some other molecular outflows. An alternative interpretation of the residual CO emission would be a compact rotating structure, distinct from the main disk, which would be a factor of $sim10-100$ more extended and massive than typical circumnuclear disks revealed in Seyferts. However, in both scenarios, our results rule out the hypothesis of a momentum-boosted molecular outflow in this AGN, despite the presence of a powerful X-ray UFO. [Abridged]
106 - L. Ballo , V. Braito (1 2015
Galaxy merging is widely accepted to be a key driving factor in galaxy formation and evolution, while the feedback from AGN is thought to regulate the BH-bulge coevolution and the star formation process. In this context, we focused on 1SXPSJ050819.8+ 172149, a local (z=0.0175) Seyfert 1.9 galaxy (L_bol~4x10^43 ergs/s). The source belongs to an IR-luminous interacting pair of galaxies, characterized by a luminosity for the whole system (due to the combination of star formation and accretion) of log(L_IR/L_sun)=11.2. We present the first detailed description of the 0.3-10keV spectrum of 1SXPSJ050819.8+172149, monitored by Swift with 9 pointings performed in less than 1 month. The X-ray emission of 1SXPSJ050819.8+172149 is analysed by combining all the Swift pointings, for a total of ~72ks XRT net exposure. The averaged Swift-BAT spectrum from the 70-month survey is also analysed. The slope of the continuum is ~1.8, with an intrinsic column density NH~2.4x10^22 cm-2, and a deabsorbed luminosity L(2-10keV)~4x10^42 ergs/s. Our observations provide a tentative (2.1sigma) detection of a blue-shifted FeXXVI absorption line (rest-frame E~7.8 keV), suggesting the discovery for a new candidate powerful wind in this source. The physical properties of the outflow cannot be firmly assessed, due to the low statistics of the spectrum and to the observed energy of the line, too close to the higher boundary of the Swift-XRT bandpass. However, our analysis suggests that, if the detection is confirmed, the line could be associated with a high-velocity (vout~0.1c) outflow most likely launched within 80r_S. To our knowledge this is the first detection of a previously unknown ultrafast wind with Swift. The high NH suggested by the observed equivalent width of the line (EW~ -230eV, although with large uncertainties), would imply a kinetic output strong enough to be comparable to the AGN bolometric luminosity.
We have carried out an extensive X-ray spectral study of the bare Seyfert-1 galaxy MCG--02--58--22 to ascertain the nature of the X-ray reprocessing media, using observations from Suzaku (2009) and simultaneous observations from XMM-Newton and NuSTAR (2016) . The most significant results of our investigation are: 1. The primary X-ray emission from the corona is constant in these observations, both in terms of the power law slope ($Gamma=1.80$) and luminosity ($L_{2-10 rm keV}= 2.55times 10^{44} $ erg/s). 2. The soft excess flux decreased by a factor of two in 2016, the Compton hump weakened/vanished in 2016, and the narrow FeK$alpha$ emission line became marginally broad ($sigma=0.35pm0.08$ keV) and its flux doubled in 2016. 3. From physical model fits we find that the normalization of the narrow component of the FeK$alpha$ line does not change in the two epochs, although the Compton hump vanishes in the same time span. Since the primary X-ray continuum does not change, we presume that any changes in the reprocessed emission must arise due to changes in the reprocessing media. Our primary conclusions are: A. The vanishing of the Compton hump in 2016 can probably be explained by a dynamic clumpy torus which is infalling/outflowing, or by a polar torus wind. B. The torus in this AGN possibly has two structures: an equatorial toroidal disk (producing the narrow FeK$alpha$ emission) and a polar component (producing the variable Compton hump), C. The reduction of the soft-excess flux by half and increase in the FeK$alpha$ flux by a factor of two in the same period cannot be adequately explained by ionized disk reflection model alone.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا