scholarly journals MODELING THE SS 433 JET BENDS

2008 ◽  
Vol 17 (10) ◽  
pp. 1925-1930 ◽  
Author(s):  
H. L. MARSHALL ◽  
CLAUDE R. CANIZARES ◽  
NORBERT S. SCHULZ ◽  
SEBASTIAN HEINZ ◽  
TODD C. HILLWIG ◽  
...  

We fit Chandra HETGS data obtained for the unusual X-ray binary SS 433. While line strengths and continuum levels hardly change, the jet Doppler shifts show aperiodic variations that probably result from shocks in interactions with the local environment. The X-ray and optical emission line regions are found to be related but not coincident as the optical line emission persists for days while the X-ray emission lines fade in less than 5000 s. The X-ray spectrum of the blueshifted jet shows over two dozen emission lines from plasma at a variety of temperatures. The emission measure distribution derived from the spectrum can be used to test jet cooling models.

2020 ◽  
Vol 6 (27) ◽  
pp. eaay9711 ◽  
Author(s):  
D. Krishnarao ◽  
R. A. Benjamin ◽  
L. M. Haffner

Optical emission lines are used to categorize galaxies into three groups according to their dominant central radiation source: active galactic nuclei, star formation, or low-ionization (nuclear) emission regions [LI(N)ERs] that may trace ionizing radiation from older stellar populations. Using the Wisconsin H-Alpha Mapper, we detect optical line emission in low-extinction windows within eight degrees of Galactic Center. The emission is associated with the 1.5-kiloparsec-radius “Tilted Disk” of neutral gas. We modify a model of this disk and find that the hydrogen gas observed is at least 48% ionized. The ratio [NII] λ6584 angstroms/Hα λ6563 angstroms increases from 0.3 to 2.5 with Galactocentric radius; [OIII] λ5007 angstroms and Hβ λ4861 angstroms are also sometimes detected. The line ratios for most Tilted Disk sightlines are characteristic of LI(N)ER galaxies.


2007 ◽  
Vol 3 (S245) ◽  
pp. 185-188
Author(s):  
Christopher P. O'Dea ◽  
Alice Quillen ◽  
Nicholas Zufelt ◽  
Jaehong Park ◽  
Alastair Edge ◽  
...  

AbstractWe present first results from an imaging survey with the Spitzer Space Telescope of 62 brightest cluster galaxies with optical line emission located in the cores of X-ray luminous clusters selected from the ROSAT All-Sky Survey. We find that 1/3 of these sources have signs of excess infrared emission; 22 objects of 62 are detected at 70 μm and 19 have 8 to 5.8 μm flux ratios above 0.98. The strength of the excess emission correlates with the luminosity of the optical emission lines. Excluding the four systems dominated by an AGN, the excess mid-infrared emission in the remaining brightest cluster galaxies is likely powered by star formation. We find a correlation between mass deposition rate from a cooling flow model for the X-ray emission and the star formation rate estimated from the infrared luminosity. The star formation rates are 1/10 to 1/100 of the mass deposition rates expected in the absence of heating suggesting that the re-heating of the ICM is generally very effective in reducing the amount of mass cooling from the hot phase.


2019 ◽  
Vol 623 ◽  
pp. A47 ◽  
Author(s):  
Idel Waisberg ◽  
Jason Dexter ◽  
Pierre-Olivier Petrucci ◽  
Guillaume Dubus ◽  
Karine Perraut

Context. The microquasar SS 433 is the only known steady supercritical accretor in the Galaxy. It is well-known for its relativistic baryonic jets, but the system also drives equatorial outflows. These have been routinely detected in radio images, and components associated with a circumbinary disk have also been suggested in optical emission lines. Aims. We aim to spatially resolve the regions producing the stationary emission lines of SS 433 to shed light on its circumbinary structure and outflows. With an estimated binary orbit size of ≲0.1 mas, this requires optical interferometry. Methods. We use the optical interferometer VLTI+GRAVITY to spatially resolve SS 433 in the near-infrared K band at high spectral resolution (R ≈ 4000) on three nights in July 2017. This is the second such observation, after the first one in July 2016. Results. The stationary Brγ line in the 2017 observation is clearly dominated by an extended ∼1 mas ∼ 5 AU circumbinary structure perpendicular to the jets with a strong rotation component. The rotation direction is retrograde relative to the jet precession, in accordance with the slaved disk precession model. The structure has a very high specific angular momentum and is too extended to be a stable circumbinary disk in Keplerian rotation; interpreting it as such leads to a very high enclosed mass M ≳ 400 M⊙. We instead interpret it as the centrifugal ejection of the circumbinary disk, with the implication that there must be an efficient transfer of specific angular momentum from the binary to the disk. We suggest that the equatorial outflows sometimes seen in radio images result from similar episodes of circumbinary disk centrifugal ejection. In addition to the equatorial structure, we find a very extended ∼6 mas ∼ 30 AU spherical wind component to the Brγ line: the entire binary is engulfed in an optically thin spherical line emission envelope.


1996 ◽  
Vol 152 ◽  
pp. 105-112 ◽  
Author(s):  
Nancy S. Brickhouse

Extreme ultraviolet spectra of Capella, obtained at various orbital phases over the past two years by the EUVE satellite, show strong emission lines from a continuous distribution of temperatures (~ 105 − 107.3 K). In addition to the strong He II λ303.8, the spectra are dominated by emission lines of highly ionized iron. Strong lines of Fe IX, XV, XVI, and XVIII–XXIV are used to construct emission measure distributions for the individual pointings, which show several striking features, including a minimum near 106 K and a local maximum at 106.8 K. Furthermore, intensities of the highest temperature lines (Te > 107 K) show variations (factors of 2–3) at different orbital phases, while the lower temperature Fe lines show variations of about 30% or less. The low variability of most of the strong low temperature features motivates a detailed analysis of the summed spectrum. With ~ 280 ks of total exposure time, we have measured over 200 emission features with S/N ≥ 3.0 in the summed spectrum. We report here initial results from the analysis of this spectrum. We can now identify lines of Fe VIII and X–XIV, as well as a number of electron density and abundance diagnostic lines.We also report here the first direct measurement of the continuum flux around ~ 100 Å in a cool star atmosphere with EUVE. The continuum flux can be predicted from the emission measure model based on Fe line emission, and demonstrates that the Fe/H abundance ratio is close to the solar photospheric value.


1990 ◽  
Vol 139 ◽  
pp. 157-169
Author(s):  
R. J. Reynolds

Diffuse galactic Hα emission appears to cover the entire sky with an intensity that ranges from 3–12 R near the galactic equator to 0.25–0.8 R near the galactic poles. Observations of this H-recombination line and the forbidden lines, [S II] 6716 Å, [N II] 6583 Å, and [O III] 5007 Å, indicate that the emission originates from a low-density, 2–3 kpc thick layer of warm (~104 K), ionized interstellar gas that has an emission-line spectrum significantly different from that of the traditional, more localized H II regions. Along a line perpendicular to the galactic disk, the mean emission measure of this layer is 4.5 cm−6 pc, and the column density of the H+ is 2 × 1020 cm−2. The origin of this diffuse ionization is not yet clear; however, its existence requires the equivalent of about 14% of the total ionizing photon flux from O stars or nearly all of the power injected into the ISM by supernova. This optically emitting gas also may be a nonnegligible source of diffuse emission in the far ultraviolet (FUV) and infrared (IR).


2017 ◽  
Vol 362 (4) ◽  
Author(s):  
Feng Li ◽  
Qirong Yuan ◽  
Weihao Bian ◽  
Xi Chen ◽  
Pengfei Yan

2003 ◽  
Vol 47 (6-7) ◽  
pp. 481-485 ◽  
Author(s):  
R Fender ◽  
S Migliari ◽  
M Méndez
Keyword(s):  
X Ray ◽  

2005 ◽  
Vol 634 (1) ◽  
pp. 161-168 ◽  
Author(s):  
T. M. Heckman ◽  
A. Ptak ◽  
A. Hornschemeier ◽  
G. Kauffmann

2011 ◽  
Vol 20 (3) ◽  
pp. 442-447
Author(s):  
G. La Mura ◽  
S. Ciroi ◽  
V. Cracco ◽  
D. Ilić ◽  
L. Č. Popović ◽  
...  

Abstract In this contribution we report on the study of the optical emission lines and X-ray spectra of a sample of Type 1 AGNs, collected from the SDSS database and observed by the XMM-Newton satellite. Using different instruments onboard XMM, we identify the spectral components of the soft and hard energy bands (in the range from 0.3 keV to 10 keV). The properties of the X-ray continuum and of the Fe Kα line feature are related to the optical broad emission line profiles and intensity ratios. The resulting picture of emission, absorption and reflection processes is interpreted by means of a structural model of the broad line region, developed on the basis of independent optical and radio observations.


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