Carbon and oxygen X-ray line emission from the interstellar medium

1982 ◽  
Vol 253 ◽  
pp. 131 ◽  
Author(s):  
H. W. Schnopper ◽  
J. P. Delvaille ◽  
R. Rocchia ◽  
C. Blondel ◽  
C. Cheron ◽  
...  
Keyword(s):  
Interstellar Medium ◽  
Line Emission ◽  
X Ray

scholarly journals Observing Soft X-ray Line Emission from the Interstellar Medium with X-ray Calorimeter on a Sounding Rocket

1990 ◽  
Vol 115 ◽  
pp. 361-364
Author(s):  
J. Zhang ◽  
B. Edwards ◽  
M. Juda ◽  
R. Kelley ◽  
G. Madejski ◽  
...  
Keyword(s):  
Interstellar Medium ◽  
Supernova Remnants ◽  
Line Emission ◽  
Aluminum Foil ◽  
High Spectral Resolution ◽  
Sounding Rocket ◽  
Preliminary Design ◽  
High Quantum Efficiency ◽  
Equilibrium Plasma ◽  
X Ray

AbstractWe have been developing X-ray calorimeters that have high spectral resolution and high quantum efficiency. For an X-ray calorimeter working at 0.1 K, the energy resolution ideally can be as good as one eV for a practical detector. A detector with a resolution of 17 eV FWHM at 6 keV has been constructed. We expect to be able to improve this by a factor of two or more. With X-ray calorimeters flown on a sounding rocket, we should be able to observe soft X-ray line emission from the interstellar medium over the energy range 0.07 to 1 keV. Here we present a preliminary design for an X-ray calorimeter rocket experiment and the spectrum which might be observed from an equilibrium plasma. For later X-ray calorimeter sounding rocket experiments, we plan to add an aluminum foil mirror with collecting area of about 400 cm2 to observe line features from bright supernova remnants.

scholarly journals The VLT/MUSE view of the central galaxy in Abell 2052

2018 ◽  
Vol 612 ◽  
pp. A19 ◽  
Author(s):  
Barbara Balmaverde ◽  
Alessandro Capetti ◽  
Alessandro Marconi ◽  
Giacomo Venturi
Keyword(s):  
Interstellar Medium ◽  
Line Emission ◽  
Emission Lines ◽  
Expansion Velocity ◽  
Direct Estimate ◽  
X Ray ◽  
Star Forming ◽  
Star Forming Regions ◽  
The North ◽  
Integral Field Spectrograph

We report observations of the radio galaxy 3C 317 (at z = 0.0345) located at the center of the Abell cluster A2052, obtained with the VLT/MUSE integral field spectrograph. The Chandra images of this cluster show cavities in the X-ray emitting gas, which were produced by the expansion of the radio lobes inflated by the active galactic nucleus (AGN). Our exquisite MUSE data show with unprecedented detail the complex network of line emitting filaments enshrouding the northern X-ray cavity. We do not detect any emission lines from the southern cavity, with a luminosity asymmetry between the two regions higher than ~75. The emission lines produced by the warm phase of the interstellar medium (WIM) enable us to obtain unique information on the properties of the emitting gas. We find dense gas (up to 270 cm−3) that makes up part of a global quasi spherical outflow that is driven by the radio source, and obtain a direct estimate of the expansion velocity of the cavities (265 km s−1). The emission lines diagnostic rules out ionization from the AGN or from star-forming regions, suggesting instead ionization from slow shocks or from cosmic rays. The striking asymmetric line emission observed between the two cavities contrasts with the less pronounced differences between the north and south sides in the hot gas; this represents a significant new ingredient for our understanding of the process of the exchange of energy between the relativistic plasma and the external medium. We conclude that the expanding radio lobes displace the hot tenuous phase of the interstellar medium (ISM), but also impact the colder and denser ISM phases. These results show the effects of the AGN on its host and the importance of radio mode feedback.

scholarly journals Resonant Scattering Effect on the Soft X-Ray Line Emission from the Hot Interstellar Medium. I. Galactic Bulges

2018 ◽  
Vol 861 (2) ◽  
pp. 138 ◽  
Author(s):  
Yang Chen ◽  
Q. Daniel Wang ◽  
Gao-Yuan Zhang ◽  
Shuinai Zhang ◽  
Li Ji
Keyword(s):  
Interstellar Medium ◽  
Line Emission ◽  
Resonant Scattering ◽  
X Ray ◽  
Scattering Effect

Iron K-Line Emission from X-Ray Binaries

1988 ◽  
Vol 102 ◽  
pp. 47-50
Author(s):  
K. Masai ◽  
S. Hayakawa ◽  
F. Nagase
Keyword(s):  
Accretion Disk ◽  
Radiative Recombination ◽  
Characteristic Temperature ◽  
Line Emission ◽  
Ionization Front ◽  
Continuum Radiation ◽  
X Ray ◽  
Low Mass ◽  
X Ray Binaries

AbstractEmission mechanisms of the iron Kα-lines in X-ray binaries are discussed in relation with the characteristic temperature Txof continuum radiation thereof. The 6.7 keV line is ascribed to radiative recombination followed by cascades in a corona of ∼ 100 eV formed above the accretion disk. This mechanism is attained for Tx≲ 10 keV as observed for low mass X-ray binaries. The 6.4 keV line observed for binary X-ray pulsars with Tx> 10 keV is likely due to fluorescence outside the He II ionization front.

scholarly journals Silicon in the solar corona

1965 ◽  
Vol 23 ◽  
pp. 115-123
Author(s):  
K. G. Widing ◽  
J. R. Porter
Keyword(s):  
Solar Corona ◽  
Relative Intensity ◽  
Line Emission ◽  
X Ray ◽  
Resonance Transitions ◽  
Spectral Ranges

Resonance lines of coronal ions of silicon are prominent in the spectral ranges 40–62 Å and 254–356 Å.An unexpected feature of the soft X-ray spectrum is the weakness or absence of the resonance lines of iron in ionization stages XI through XV.A second feature is the prominence of lines of the type (3d → 2p) relative to the resonance transitions (3p → 2s) in Li-like and Beryllium-like spectra. It is suggested that the upper levels (3d) are excited by quadrupole collisions from the ground 2s or 2s2levels.The intensity of the soft X-ray lines relative to the resonance lines in the 300 Å region seems to be more consistent with temperatures well above one million degrees than with temperatures as low as 700000°K, but the data are not adequate for a precise comparison. The relative intensity of the line emission from the various stages of silicon ionization may be interpreted as indicating that the ionization of silicon peaks in stages IX and X.The abundances of C, Mg, S, and Al relative to silicon do not seem to be greatly different from the chromospheric abundances reported by Pottasch or with the photospheric abundances.

scholarly journals X-ray Properties of 3C 111: Separation of Primary Nuclear Emission and Jet Continuum

Universe ◽  
2020 ◽  
Vol 6 (11) ◽  
pp. 219
Author(s):  
Elena Fedorova ◽  
B.I. Hnatyk ◽  
V.I. Zhdanov ◽  
A. Del Popolo
Keyword(s):  
Accretion Disk ◽  
Power Law ◽  
Line Emission ◽  
High Energy ◽  
Power Law Model ◽  
X Ray ◽  
Additional Information ◽  
Observational Dataset ◽  
Simple Power ◽  
Photon Index

3C111 is BLRG with signatures of both FSRQ and Sy1 in X-ray spectrum. The significant X-ray observational dataset was collected for it by INTEGRAL, XMM-Newton, SWIFT, Suzaku and others. The overall X-ray spectrum of 3C 111 shows signs of a peculiarity with the large value of the high-energy cut-off typical rather for RQ AGN, probably due to the jet contamination. Separating the jet counterpart in the X-ray spectrum of 3C 111 from the primary nuclear counterpart can answer the question is this nucleus truly peculiar or this is a fake “peculiarity” due to a significant jet contribution. In view of this question, our aim is to estimate separately the accretion disk/corona and non-thermal jet emission in the 3C 111 X-ray spectra within different observational periods. To separate the disk/corona and jet contributions in total continuum, we use the idea that radio and X-ray spectra of jet emission can be described by a simple power-law model with the same photon index. This additional information allows us to derive rather accurate values of these contributions. In order to test these results, we also consider relations between the nuclear continuum and the line emission.

scholarly journals Challenges and Techniques for Simulating Line Emission

Galaxies ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 100 ◽  
Author(s):  
Karen Olsen ◽  
Andrea Pallottini ◽  
Aida Wofford ◽  
Marios Chatzikos ◽  
Mitchell Revalski ◽  
...  
Keyword(s):  
Interstellar Medium ◽  
Emission Line ◽  
Line Emission ◽  
Emission Lines ◽  
Synthetic Spectra ◽  
Recent Advances ◽  
The Future ◽  
Important Quality ◽  
Circumgalactic Medium

Modeling emission lines from the millimeter to the UV and producing synthetic spectra is crucial for a good understanding of observations, yet it is an art filled with hazards. This is the proceedings of “Walking the Line”, a 3-day conference held in 2018 that brought together scientists working on different aspects of emission line simulations, in order to share knowledge and discuss the methodology. Emission lines across the spectrum from the millimeter to the UV were discussed, with most of the focus on the interstellar medium, but also some topics on the circumgalactic medium. The most important quality of a useful model is a good synergy with observations and experiments. Challenges in simulating line emission are identified, some of which are already being worked upon, and others that must be addressed in the future for models to agree with observations. Recent advances in several areas aiming at achieving that synergy are summarized here, from micro-physical to galactic and circum-galactic scale.

scholarly journals 1/4 Ke V Diffuse Background and the Local Interstellar Medium

1989 ◽  
Vol 120 ◽  
pp. 536-536
Author(s):  
S.L. Snowden
Keyword(s):  
Interstellar Medium ◽  
Filling Factor ◽  
Thermal Emission ◽  
Mean Free Path ◽  
Physical Parameters ◽  
X Rays ◽  
Local Interstellar Medium ◽  
X Ray ◽  
Diffuse Background ◽  
X Ray Background

The 1/4 keV diffuse X-ray background (SXRB) is discussed in relation to the local interstellar medium (LISM). The most likely source for these soft X-rays is thermal emission from a hot diffuse plasma. The existence of a non-zero flux from all directions and the short ISM mean free path of these X-rays (1020HI cm-2), coupled with ISM pressure constraints, imply that the plasma has a local component and that it must, at least locally (nearest hundred parsecs), have a large filling factor. Our understanding of the geometry and physical parameters of the LISM is therefore directly tied to our understanding of the SXRB.

scholarly journals Measurement and interpretation of the polarization of the x-ray line emission of heliumlike Fe XXV excited by an electron beam

1996 ◽  
Vol 53 (6) ◽  
pp. 3974-3981 ◽  
Author(s):  
P. Beiersdorfer ◽  
D. A. Vogel ◽  
K. J. Reed ◽  
V. Decaux ◽  
J. H. Scofield ◽  
...  
Keyword(s):  
Electron Beam ◽  
Line Emission ◽  
X Ray
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