scholarly journals Red QSOs in the MBH-M∗ plane

2013 ◽  
Vol 9 (S304) ◽  
pp. 195-198
Author(s):  
Angela Bongiorno
Keyword(s):  
Infrared Spectra ◽  
Near Infrared ◽  
Intermediate Phase ◽  
High Redshift ◽  
X Ray ◽  
Near Infrared Spectra ◽  
Major Merger ◽  
Local Relation ◽  
Stellar Masses

AbstractWe present new results on the the MBH-M∗ relation of X-ray obscured, red QSOs at high redshift (1.2<z<2.6). The sample is made of 21 red QSOs, nine of them are new sources for which near-infrared spectra have been obtained with SINFONI and XShooter observations at ESO VLT, and show a broad Hα component. The rest of the sample (12 sources) is made of sources taken from the literature with similar properties. From the broad Hα line we have computed the BH masses through the virial formula while stellar masses have been obtained through multi-component SED fitting.We find that red QSOs preferentially lie on the local relation up to z ~ 2.6 with the most massive objects mainly located above it. We also studied the evolution of these sources on the MBH-M∗ plane compared to a sample of optically blue type–1 QSOs and we find that obscured red QSOs show a constant MBH/M∗ ratio consistent/slightly higher than the local one but lower than what has been found for blue QSOs. These sources may represent the intermediate phase (blow-out phase) between the major-merger induced starbursts which appear as ULIRGs and SMGs and the optical type–1 blue QSOs which are revealed once the dust and nuclear gas is cleared up.

scholarly journals Improving spatial synchronization between X-ray and near-infrared spectra information to predict wood density profiles

2020 ◽  
Vol 54 (5) ◽  
pp. 1151-1164 ◽  
Author(s):  
Ana Alves ◽  
Andrea Hevia ◽  
Rita Simões ◽  
Juan Majada ◽  
Ricardo Alia ◽  
...  
Keyword(s):  
Wood Density ◽  
Infrared Spectra ◽  
Near Infrared ◽  
Spatial Synchronization ◽  
Density Profiles ◽  
X Ray ◽  
Near Infrared Spectra

The near-infrared spectra of low-mass X-ray binaries and related objects

1991 ◽  
Vol 373 ◽  
pp. 228 ◽  
Author(s):  
A. P. Cowley ◽  
P. C. Schmidtke ◽  
D. Crampton ◽  
J. B. Hutchings ◽  
M. Bolte
Keyword(s):  
Infrared Spectra ◽  
Near Infrared ◽  
X Ray ◽  
Near Infrared Spectra ◽  
Low Mass ◽  
X Ray Binaries

scholarly journals Long-term NIR variability in the UKIDSS Ultra Deep Survey: a new probe of AGN activity at high redshift

2020 ◽  
Vol 493 (2) ◽  
pp. 3026-3035 ◽  
Author(s):  
E Elmer ◽  
O Almaini ◽  
M Merrifield ◽  
W G Hartley ◽  
D T Maltby ◽  
...  
Keyword(s):  
Near Infrared ◽  
High Redshift ◽  
Galactic Nuclei ◽  
Host Galaxies ◽  
X Ray ◽  
X Ray Imaging ◽  
Sky Survey ◽  
Deep Survey ◽  
Stellar Masses

ABSTRACT We present the first attempt to select active galactic nuclei (AGN) using long-term near-infrared (NIR) variability. By analysing the K-band light curves of all the galaxies in the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra Deep Survey, the deepest NIR survey over ∼1 deg2, we have isolated 393 variable AGN candidates. A comparison to other selection techniques shows that only half of the variable sources are also selected using either deep Chandra X-ray imaging or Infrared Array Camera (IRAC) colour selection, suggesting that using NIR variability can locate AGN that are missed by more standard selection techniques. In particular, we find that long-term NIR variability identifies AGN at low luminosities and in host galaxies with low stellar masses, many of which appear relatively X-ray quiet.

scholarly journals Near‐Infrared Spectra of the Black Hole X‐Ray Binary A0620‐00

2007 ◽  
Vol 663 (2) ◽  
pp. 1215-1224 ◽  
Author(s):  
Cynthia S. Froning ◽  
Edward L. Robinson ◽  
Martin A. Bitner
Keyword(s):  
Black Hole ◽  
Infrared Spectra ◽  
Near Infrared ◽  
X Ray ◽  
Near Infrared Spectra

scholarly journals LBT/ARGOS adaptive optics observations of z ∼ 2 lensed galaxies

2018 ◽  
Vol 618 ◽  
pp. A36 ◽  
Author(s):  
M. Perna ◽  
M. Curti ◽  
G. Cresci ◽  
F. Mannucci ◽  
S. Rabien ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Infrared Spectra ◽  
Spectral Resolution ◽  
Near Infrared ◽  
High Redshift ◽  
Formation Rate ◽  
Operation Mode ◽  
Chemical Properties ◽  
Flux Ratio ◽  
Near Infrared Spectra

Aims. Gravitationally lensed systems allow a detailed view of galaxies at high redshift. High spatial- and spectral-resolution measurements of arc-like structures can offer unique constraints on the physical and dynamical properties of high-z systems. Methods. We present near-infrared spectra centred on the gravitational arcs of six known z ∼ 2 lensed star-forming galaxies of stellar masses of 109−11 M⊙ and star formation rate (SFR) in the range between 10 and 400 M⊙ yr−1. Ground layer adaptive optics (AO)-assisted observations are obtained at the Large Binocular Telescope (LBT) with the LUCI spectrographs during the commissioning of the ARGOS facility. We used MOS masks with curved slits to follow the extended arched structures and study the diagnostic emission lines. LBT observations are used to demonstrate the spectroscopic capabilities of ARGOS. Results. Combining spatially resolved kinematic properties across the arc-like morphologies, emission line diagnostics and archival information, we distinguish between merging and rotationally supported systems, and reveal the possible presence of ejected gas. For galaxies that have evidence for outflows, we derive outflow energetics and mass-loading factors compatible with those observed for stellar winds in local and high-z galaxies. We also use flux ratio diagnostics to derive gas-phase metallicities. The low signal-to-noise ratio in the faint Hβ and nitrogen lines allows us to derive an upper limit of ≈0.15 dex for the spatial variations in metallicity along the slit for the lensed galaxy J1038. Conclusions. Analysed near-infrared spectra presented here represent the first scientific demonstration of performing AO-assisted multi-object spectroscopy with narrow curved-shape slits. The increased angular and spectral resolution, combined with the binocular operation mode with the 8.4 m wide eyes of LBT, will allow the characterisation of kinematic and chemical properties of a large sample of galaxies at high-z in the near future.

Rapid Determining Contents of the Rhubarb Anthraquinones Compounds by Support Vector Machines Modeling based on Near Infrared Spectra

2020 ◽  
Vol 16 ◽  
Author(s):  
Linqi Liu ◽  
JInhua Luo ◽  
Chenxi Zhao ◽  
Bingxue Zhang ◽  
Wei Fan ◽  
...  
Keyword(s):  
Infrared Spectra ◽  
Near Infrared ◽  
Mean Squared Error ◽  
Rapid Determination ◽  
Partial Least Square ◽  
Least Square ◽  
Support Vector ◽  
Near Infrared Spectra ◽  
Aloe Emodin ◽  
Relative Differences

BACKGROUND: Measuring medicinal compounds to evaluate their quality and efficacy has been recognized as a useful approach in treatment. Rhubarb anthraquinones compounds (mainly including aloe-emodin, rhein, emodin, chrysophanol and physcion) are its main effective components as purgating drug. In the current Chinese Pharmacopoeia, the total anthraquinones content is designated as its quantitative quality and control index while the content of each compound has not been specified. METHODS: On the basis of forty rhubarb samples, the correlation models between the near infrared spectra and UPLC analysis data were constructed using support vector machine (SVM) and partial least square (PLS) methods according to Kennard and Stone algorithm for dividing the calibration/prediction datasets. Good models mean they have high correlation coefficients (R2) and low root mean squared error of prediction (RMSEP) values. RESULTS: The models constructed by SVM have much better performance than those by PLS methods. The SVM models have high R2 of 0.8951, 0.9738, 0.9849, 0.9779, 0.9411 and 0.9862 that correspond to aloe-emodin, rhein, emodin, chrysophanol, physcion and total anthraquinones contents, respectively. The corresponding RMSEPs are 0.3592, 0.4182, 0.4508, 0.7121, 0.8365 and 1.7910, respectively. 75% of the predicted results have relative differences being lower than 10%. As for rhein and total anthraquinones, all of the predicted results have relative differences being lower than 10%. CONCLUSION: The nonlinear models constructed by SVM showed good performances with predicted values close to the experimental values. This can perform the rapid determination of the main medicinal ingredients in rhubarb medicinal materials.

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