scholarly journals A 2.5-5 μm spectroscopic study of hard X-ray selected AGNs with AKARI

2013 ◽  
Vol 9 (S304) ◽  
pp. 66-67
Author(s):  
A. Castro ◽  
T. Miyaji ◽  
M. Shirahata ◽  
S. Oyabu ◽  
D. Clark ◽  
...  
Keyword(s):  
Star Formation ◽  
Neutral Hydrogen ◽  
Infrared Camera ◽  
X Ray ◽  
Star Formation Activity ◽  
Hydrogen Column Density ◽  
Polycyclic Aromatic ◽  
Low X

AbstractWe explore the relationships between the 3.3 μm polycyclic aromatic hydrocarbon (PAH) feature and active galactic nucleus (AGN) properties of a sample of 54 hard X-ray selected bright AGNs, including both Seyfert 1 and Seyfert 2 type objects, using the InfraRed Camera (IRC) on board the infrared astronomical satellite AKARI. The sample is selected from the 9-month Swift/BAT survey in the 14-195 keV band and all of them have measured X-ray spectra at E ≲ 10 keV. These X-ray spectra provide measurements of the neutral hydrogen column density (NH) towards the AGNs. We use the 3.3 μm PAH luminosity (L3.3μm) as a proxy for star formation activity and hard X-ray luminosity (L14-195keV) as an indicator of the AGN activity. We searched for possible difference of star-formation activity between type 1 (un-absorbed) and type 2 (absorbed) AGNs. Our regression analysis of log L14-195keV versus log L3.3μm shows a positive correlation and the slope seems steeper for type 1/unobscured AGNs than that of type 2/obscured AGNs. The same trend has been found for the log (L14-195keV/MBH) versus log (L3.3μm/MBH) correlation. Our analysis show that the circum-nuclear star-formation is more enhanced in type 2/absorbed AGNs than type 1/un-absorbed AGNs for low X-ray luminosity/low Eddington ratio AGNs.

scholarly journals Environmental Effects on Properties of Type 2 QSOs

2009 ◽  
Vol 5 (S267) ◽  
pp. 106-106
Author(s):  
Lin-wen Chen ◽  
Li-Ting Hsu
Keyword(s):  
Column Density ◽  
Neutral Hydrogen ◽  
Photometric Redshifts ◽  
X Ray ◽  
Sky Survey ◽  
Hydrogen Column Density ◽  
Population Figure ◽  
Two Populations ◽  
Projected Distance

Type 2 QSOs (QSO2s) are intrinsically luminous QSOs embedded in dusty environments. In this work, we study the radio, optical, and soft X-ray properties of 887 optically selected [O III]-based QSO2s (Reyes et al. 2008) at z<0.83 to investigate the connection between QSO2s and their environments. We use SDSS data to measure the luminosity-limited galaxy counts in a volume centered on each QSO2 and defined by Δ z<0.1 (based on photometric redshifts) and within a projected distance of 1.5 Mpc of the QSO2 (δ1.5Mpc). We used ROSAT All Sky Survey (RASS) data to estimate the X-ray excess. Hsu & Chen (2010), after correcting for Galactic absorption, obtain a lower limit for the intrinsic neutral hydrogen column density (NH) toward each of the QSO2s. About 50% of these sources have NH > 1022 cm−2. We take this value as a threshold to subdivide QSO2s into high- and low-NH groups, and compare their environments. The distributions δ1.5Mpc of the two populations show that, in regions of higher galaxy density, QSO2s are dominated by the high-NH population (Figure 1), suggesting a closer connection between more obscured QSO2s and surrounding galaxies.

scholarly journals Multiple AGN activity during the BCG assembly of XDCPJ0044.0-2033 at z ∼ 1.6

2020 ◽  
Vol 498 (2) ◽  
pp. 2719-2733
Author(s):  
A Travascio ◽  
A Bongiorno ◽  
P Tozzi ◽  
R Fassbender ◽  
F De Gasperin ◽  
...  
Keyword(s):  
Star Formation ◽  
Galaxy Clusters ◽  
Elliptical Galaxy ◽  
Galactic Nuclei ◽  
Cluster Galaxy ◽  
X Ray ◽  
The Core ◽  
Galaxy Population

ABSTRACT Undisturbed galaxy clusters are characterized by a massive and large elliptical galaxy at their centre, i.e. the brightest cluster galaxy (BCG). How these central galaxies form is still debated. According to most models, a typical epoch for their assembly is $z$ ∼ 1–2. We have performed a detailed multiwavelength analysis of the core of XMM–Newton Distant Cluster Project (XDCP) J0044.0-2033 (XDCP0044), one of the most massive and densest galaxy clusters currently known at redshift $z$ ∼ 1.6, whose central galaxy population shows high star formation compared to lower z clusters and an X-ray active galactic nuclei (AGN) located close to its centre. SINFONI J-, H-, and KMOS YJ-, H-bands spectroscopic data have been analysed, together with deep archival HST photometric data in F105W, F140W, and F160W bands, Chandra X-ray, radio JVLA data at 1–2 GHz, and ALMA band-6 observations. In the very central region of the cluster (∼70 kpc × 70 kpc), two systems of interacting galaxies have been identified and studied (Complex A and B), with a total of seven confirmed cluster members. These galaxies show perturbed morphologies and three of them show signs of AGN activity. In particular, two type-1 AGN with typical broad lines have been found at the centre of each complex (both of them X-ray obscured and highly accreting with $\rm \lambda _{Edd}\sim 0.4-0.6$), while a type-2 AGN has been discovered in Complex A. The AGN at the centre of Complex B is also detected in X-ray, while the other two are spatially related to radio emission. The three AGN provide one of the closest AGN triple at $z$ &gt; 1 revealed so far with a minimum (maximum) projected distance of 10 (40) kpc. The observation of high star formation, merger signatures, and nuclear activity in the core of XDCP0044 suggests that all these processes are key ingredients in shaping the nascent BCG. According to our data, XDCP0044 could form a typical massive galaxy of $M_{\star }\sim 10^{12} \, \mathrm{M}_{\odot }$, hosting a black hole of $\rm 2 \times 10^8\!-\!10^9 \, \mathrm{M}_{\odot }$, in a time-scale of the order of ∼2.5 Gyr.

The properties of the dusty inner regions of nearby QSOs

2019 ◽  
Vol 15 (S356) ◽  
pp. 95-95
Author(s):  
Itziar Aretxaga
Keyword(s):  
Star Formation ◽  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Stellar Objects ◽  
X Ray ◽  
Mir Spectroscopy ◽  
Polycyclic Aromatic ◽  
Quasi Stellar Objects

AbstractWe present MIR spectroscopy and photometry obtained with CanariCam on the 10.4 m Gran Telescopio CANARIAS for a sample of 20 nearby, MIR bright and X-ray luminous quasi-stellar objects (QSOs). We find that for the majority of QSOs the MIR emission is unresolved at angular scales ∼0.3 arcsec. We derive the properties of the dusti tori that surround the nucleus based on these observations and find significant differences in the parameters compared with a sample of Seyfert 1 and 2 nuclei. We also find evidence for polycyclic aromatic hydrocarbon (PAH) features in the spectra, indicative of star formation, more centrally peaked (on scales of a few hundred pc) than previously believed.

AGN1 vs AGN2 dichotomy as seen from the point of view of ionized outflows

2019 ◽  
Vol 15 (S356) ◽  
pp. 96-96
Author(s):  
Eleonora Sani
Keyword(s):  
Accretion Rate ◽  
Point Of View ◽  
Emission Lines ◽  
Black Hole Mass ◽  
X Ray ◽  
Bolometric Luminosity ◽  
Wide Range ◽  
Strong Contrast

AbstractI present a detailed study of ionized outflows in a large sample of 650 hard X-ray detected AGN. Taking advantage of the legacy value of the BAT AGN Spectroscopic Survey (BASS, DR1), we are able to reveal the faintest wings of the [OIII] emission lines associated with outflows. The sample allows us to derive the incidence of outflows covering a wide range of AGN bolometric luminosity and test how the outflow parameters are related with various AGN power tracers, such as black hole mass, Eddington ratio, luminosity. I’ll show how ionized outflows are more frequently found in type 1.9 and type 1 AGN (50% and 40%) with respect to the low fraction in type 2 AGN (20%). Within such a framework, I’ll demonstrate how type 2 AGN outflows are almost evenly balanced between blue- and red-shifted winds. This, in strong contrast with type 1 and type 1.9 AGN outflows which are almost exclusively blue-shifted. Finally, I’ll prove how the outflow occurrence is driven by the accretion rate, whereas the dependence of outflow properties with respect to the other AGN power tracers happens to be quite mild.

scholarly journals There is a Correlation between Fragility Fractures of the Pelvis and a Circle-Type Morphology of the True Pelvis, but Not with Pelvic Incidence

2021 ◽  
pp. 1-6
Author(s):  
Matthias Spalteholz ◽  
Matthias Spalteholz ◽  
Gulow Jens ◽  
Pap Geza
Keyword(s):  
Pelvic Incidence ◽  
Fragility Fractures ◽  
Statistical Correlation ◽  
X Ray ◽  
Lack Of Information ◽  
The Mean ◽  
Fracture Types ◽  
Type 3

Purpose: Osteoporosis is a major risk factor for the development of fragility fractures of the pelvis (FFP). There is a lack of information about the influence of anatomical conditions such as Pelvic Incidence and Pelvic Ratio (DT/DS ratio) on this kind of fractures. Methods: This is a monocentric retrospective analysis. X-ray images of the lumbar spine and pelvis and 3D-MPR CT reconstructions of the pelvis were analysed to determine Pelvic Incidence (PI) and Pelvic Ratio (PR) in 141 fragility fractures of the pelvis. Statistical analyses were performed to examine the correlation between these spinopelvic parameters and fragility fractures of the pelvis. Results: A total of 141 fragility fractures of the pelvis (14 men = 9.93%, 127 women = 90.07%) were analysed. According to the FFP-classification we recognized FFP type 1 fractures in 19.15%, FFP type 2 in 41.13%, FFP type 3 in 8.51% and FFP type 4 fractures in 32.21%. The mean PI was 58.83º. There was no statistical correlation between PI and fracture types (p=0.81). The mean PR was 1.099. 57 patients (40.43%) demonstrated a DT/DS ratio ≤ 1.06, corresponding to a circle-type morphology. 24 patients (17.02%) demonstrated a DT/DS ratio ≥ 1.18, corresponding to an ellipse-type pelvis. A circle-type pelvis is significantly more often associated with fragility fractures of the pelvis than an ellipse-type morphology (p<0.001). Conclusion: The results of our work demonstrate a strong statistical correlation between the circle-type morphology of the pelvis (PR ≤ 1.06) and fragility fractures of the pelvis. There is no statistical correlation between fragility fractures of the pelvis and Pelvic Incidence.

X‐Ray Sources and Star Formation Activity in the Sagittarius B2 Cloud Observed withChandra

2002 ◽  
Vol 573 (1) ◽  
pp. 275-282 ◽  
Author(s):  
Shin‐ichiro Takagi ◽  
Hiroshi Murakami ◽  
Katsuji Koyama
Keyword(s):  
Star Formation ◽  
X Ray ◽  
Star Formation Activity

scholarly journals The Half Million Quasars (HMQ) Catalogue

2015 ◽  
Vol 32 ◽  
Author(s):  
Eric W. Flesch
Keyword(s):  
High Confidence ◽  
Bl Lac Objects ◽  
X Ray ◽  
Bl Lac

AbstractA quasar catalogue is presented with a total of 510 764 objects including 424 748 type 1 QSOs and 26 623 type 1 AGN complete from the literature to 2015 January 25. Also included are 25015 high-confidence SDSS-based photometric quasars with radio/X-ray associations, 1595 BL Lac objects, and 32783 type 2 objects. Each object is displayed with arcsecond-accurate astrometry, red and blue photometry, redshift, citations, and radio and X-ray associations where present. Also, 114 new spectroscopically confirmed quasars are presented.

Etiology analysis and x-ray diagnostics of feline odontoclastic resorbtive lesion

2020 ◽  
Vol 1 ◽  
pp. 157-162
Author(s):  
Yu. V. Mukiy ◽  
◽  
V. A. Nikolaeva ◽  
Keyword(s):  
Veterinary Medicine ◽  
Statistical Analysis ◽  
Reliable Data ◽  
Statistical Information ◽  
X Rays ◽  
X Ray ◽  
Different Types

In veterinary medicine, one of the most relevant area is dentistry of small pets. Of all dentistry diseases - 80% of cases are due to Feline odontoclastic resorptive lesion (FORL), which is more often diagnosed in cats. 35 cats have been diagnosed with den-tal disorders in vet-clinic "Altervet" for the period from November 2018 to April 2019. The analysis of the statistical information was carried out: 86 % of cats, that is 30 heads, were diagnosed FORL. The assess-ment was carried out according to the degree of tooth damage from x-rays images, and there are 2 types of resorption today: type 1 and type 2. Moreover, one of the examined cats simultaneously detected both types of FORL. Various degrees of tooth damage have been studied. Lesions of various parts of the tooth (crowns, necks, aboral and ros-tral roots of the teeth) were found, which were marked on radiographs. A statistical analysis of the incidence by breed, age, sex of animals and types of feed was conducted. The middle animal age of the disease inci-dence is 10 years. It was found that animals with pathology were nourished different types of food: mixed, dry, wet and natural. However, a greater number of cats with FORL were fed mixed (14 heads) and dry (8 heads) feed, 47 and 27%, respectively. It was found that in male this pathology is di-agnosed more often, in our case it is 73%, than in female- 27%.The disease was more common in mongrel cats – 18 heads, than in thoroughbred animals -12 heads, it turned out 60 and 40% of the number of affected animals. Reliable data on the influence of sex and breed on the occurrence of FORL has not been established.

scholarly journals Diffuse Ionised Gas in Edge-on Galaxies

1998 ◽  
Vol 15 (1) ◽  
pp. 106-110 ◽  
Author(s):  
Richard J. Rand
Keyword(s):  
Star Formation ◽  
Radio Continuum ◽  
Spatial Correlations ◽  
Hii Region ◽  
X Ray ◽  
Disk Star ◽  
Deep Imaging ◽  
Star Formation Activity ◽  
Fabry Perot ◽  
Theoretical Predictions

AbstractWe review observations of diffuse ionised gas (DIG) in edge-on spiral galaxies. Deep imaging has revealed a variety of morphologies for ‘extraplanar’ (above the HII region layer) or ‘halo’ DIG: some show widespread prominent layers of truly diffuse gas and filamentary structures, others show just one patch or a few patches of extraplanar emission, while still others show no detectable extraplanar DIG at all. The key galactic property which appears to govern the prominence of the DIG layer is the star-formation activity. Smaller-scale connections between DIG and local star formation activity can be seen in some of the galaxies.DIG halos are also related to radio continuum, X-ray and HI halos. Those galaxies with the most prominent DIG layers also have the most prominent radio halos. In NGC 891, there are spatial correlations between extraplanar DIG, radio emission, X-ray emission and HI, and these in turn are related to the underlying disk star-formation activity.Progress on identifying the sources of ionisation and heating of the gas has come from spectroscopy, imaging in different emission lines, and Fabry–Perot observations. By comparing with theoretical predictions, much evidence is found for photoionisation by disk stars as the primary ionisation and heating mechanism, but recent observations are beginning to point towards the need for additional sources of ionisation and/or heating.

scholarly journals Early Super Soft Source Spectra in RS Oph

2015 ◽  
Vol 2 (1) ◽  
pp. 222-225
Author(s):  
J.-U. Ness
Keyword(s):  
Neutral Hydrogen ◽  
Emission Lines ◽  
X Ray ◽  
Hydrogen Column Density ◽  
Recurrent Nova ◽  
Source Spectra ◽  
Short Time ◽  
First Time ◽  
Shell Ionization

Recent Swift X-ray monitoring campaigns of novae have revealed extreme levels of variability during the early super-softsource (SSS) phase. The first time this was observed was during the 2006 outburst of the recurrent nova RS Oph which was also extensively covered by grating observations with XMM-Newton and Chandra. I focus here on an XMM-Newton observation taken on day 26.1, just before Swift confirmed the start of the SSS phase, and a Chandra observation taken on day 39.7. The first observation probes the evolution of the shock emission produced by the collision of the nova ejecta with the stellar wind of the companion. The second observation contains bright SSS emission longwards of 15°A while at short wavelengths, the shock component can be seen to have hardly changed. On top of the SSS continuum, additional emission lines are clearly seen, and I show that they are much stronger than those seen on day 26.1, indicating line pumping caused by the SSS emission. The lightcurve on day 39.7 is highly variable on short time scales while the long-term Swift light curve was still variable. In 2007, we have shown that brightness variations are followed by hardness variations, lagging behind 1000 seconds. I show now that the hardness variations are owed to variations in the depth of the neutral hydrogen column density of order 25%, particularly affecting the oxygen K-shell ionization edge at 0.5 keV.

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