X-ray Emission from G359.1-0.5

International Astronomical Union Colloquium ◽

10.1017/s0252921100071359 ◽

1997 ◽

Vol 166 ◽

pp. 417-420

Author(s):

Roland Egger ◽

Xuejun Sun

Keyword(s):

Thermal Plasma ◽

Large Distance ◽

Supernova Remnant ◽

Radio Observation ◽

Plasma Model ◽

Diffuse Emission ◽

X Ray ◽

Pointed Observation

AbstractWe report on the detection of X-ray emission from the supernova remnant (SNR) G359.1-0.5 in a deep ROSAT PSPC pointed observation. The diffuse emission is well confined within the radio shell of the SNR. Its spectrum can be represented by a thermal plasma model at T ~ 1 keV and Fx ~ 2×10−11 erg cm−2 s−1 (0.1–2.0 keV) modified by the column absorption of NH ~ 3 × 1022 cm−2. This result supports the view that the source is at a large distance consistent with that from radio observation, and helps to resolve a puzzle about the SNR in previous observations.

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X-ray emission from the mixed-morphology supernova remnant HB 9

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/psaa042 ◽

2020 ◽

Vol 72 (4) ◽

Author(s):

Mariko Saito ◽

Shigeo Yamauchi ◽

Kumiko K Nobukawa ◽

Aya Bamba ◽

Thomas G Pannuti

Keyword(s):

Spectral Analysis ◽

Central Region ◽

Supernova Remnant ◽

Interstellar Matter ◽

Plasma Model ◽

Ionization Equilibrium ◽

Equilibrium Plasma ◽

X Ray ◽

Collisional Ionization ◽

Matter Component

Abstract We present the results of a spectral analysis of the central region of the mixed-morphology supernova remnant HB 9. A prior Ginga observation of this source detected a hard X-ray component above 4 keV, and the origin of this particular X-ray component is still unknown. Our results demonstrate that the extracted X-ray spectra are best represented by a model consisting of a collisional ionization equilibrium plasma with a temperature of ∼0.1–0.2 keV (interstellar matter component) and an ionizing plasma with a temperature of ∼0.6–0.7 keV and an ionization timescale of >1 × 1011 cm−3 s (ejecta component). No significant X-ray emission was found in the central region above 4 keV. The recombining plasma model reported by a previous work does not explain our spectra.

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X-ray and radio studies of SNR CTB 37B hosting the magnetar CXOU J171405.7−381031

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1656 ◽

2019 ◽

Vol 487 (4) ◽

pp. 5019-5028 ◽

Cited By ~ 1

Author(s):

Harsha Blumer ◽

Samar Safi-Harb ◽

Roland Kothes ◽

Adam Rogers ◽

Eric V Gotthelf

Keyword(s):

Supernova Remnant ◽

Small Region ◽

Diffuse Emission ◽

X Ray ◽

Evolutionary Phase ◽

Radio Studies ◽

Photon Index ◽

Southern Side ◽

Bright Emission ◽

Absorption Measurements

ABSTRACT We present a Chandra and XMM–Newton study of the supernova remnant (SNR) CTB 37B, along with archival radio observations. In radio wavelengths, the SNR CTB 37B is an incomplete shell showing bright emission from the eastern side, while the X-ray morphology shows diffuse emission from regions surrounding the magnetar CXOU J171405.7–381031. We used archival H i absorption measurements to constrain the distance to the remnant and obtain D = 9.8 ± 1.5 kpc. The X-ray spectrum of the remnant is described by a thermal model in the 1–5 keV energy range, with a temperature of kT = 1.3 ± 0.1 keV. The abundances from the spectral fits are consistent with being solar or sub-solar. A small region of diffuse emission is seen to the southern side of the remnant, best fitted by a non-thermal spectrum with an unusually hard photon index of Γ = 1.3 ± 0.3. Assuming a distance of 9.8 kpc to the SNR, we infer a shock velocity of Vs = 915 ± 70 km s−1 and an explosion energy of E = (1.8 ± 0.6) × 1050 erg. The overall imaging and spectral properties of CTB 37B favour the interpretation of a young SNR (≲6200 yr old), propagating in a low-density medium under the assumption of a Sedov evolutionary phase.

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The Diagnostics of Astrophysical Plasmas, using the Oxygen VII Soft X-Ray Lines

International Astronomical Union Colloquium ◽

10.1017/s0252921100107791 ◽

1988 ◽

Vol 102 ◽

pp. 235-238

Author(s):

A.H. Gabriel ◽

F. Bely-Dubau ◽

P. Faucher ◽

L.W. Acton

Keyword(s):

High Temperature ◽

Thermal Plasma ◽

Solar Flares ◽

Alternative Model ◽

Supernova Remnant ◽

Astrophysical Plasmas ◽

Density Measurements ◽

X Ray ◽

Line Intensities ◽

Intensity Ratios

AbstractWe present a revised theory and atomic model for the line intensities emitted by O VII, taking into account all of the processes responsible for the emission. This is used to provide a revision of the density measurements made during solar flares, as well as in an attempt to understand the spectrum of the Puppis A supernova remnant. In order to explain the strange intensity ratios observed from Puppis A, previous authors have proposed an interpretation based upon a high temperature thermal plasma (>5 106K), in a non-equilibrium ionisation state. We present here an alternative model, based upon the assumed presence of a proportion of fast non-thermal electrons imbedded in an otherwise thermal plasma at a temperature of below 1 106K. This can adequately explain the observations, without the necessity of invoking departures from ionisation balance.

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An XMM-Newton study of the supernova remnant G296.7–0.9

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312024283 ◽

2012 ◽

Vol 8 (S291) ◽

pp. 402-404

Author(s):

R. H. H. Huang ◽

C. Y. Hui ◽

L. Trepl ◽

A. K. H. Kong

Keyword(s):

Radio Emission ◽

Supernova Remnant ◽

Gamma Ray ◽

Emission Lines ◽

Plasma Model ◽

X Ray ◽

Gamma Ray Emission ◽

Spectro Imaging

AbstractWe report on XMM-Newton observations of the Galactic supernova remnant G296.7–0.9. A detailed spectro-imaging X-ray study of G296.7–0.9 was performed. We detected an incomplete shell-like X-ray structure which is located near the boundary of the radio emission at a frequency of 843 MHz. The X-ray spectrum can be best described by an absorbed ionization plasma model accompanied with metallic emission lines, which suggests the plasma is shock heated. No promising compact stellar remnant associated with G296.7–0.9 was found. No Gamma-ray emission of G296.7–0.9 from Fermi-LAT telescope was detected in our study.

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Material Structure of Microcrystalline Silicon Deposited with an Expanding Thermal Plasma

MRS Proceedings ◽

10.1557/proc-762-a.15.3 ◽

2003 ◽

Vol 762 ◽

Cited By ~ 2

Author(s):

C. Smit ◽

D.L. Williamson ◽

M.C.M. van de Sanden ◽

R.A.C.M.M. van Swaaij

Keyword(s):

Thermal Plasma ◽

Hydrogen Plasma ◽

Plasma Chemistry ◽

Plasma Source ◽

Growth Direction ◽

Interaction Time ◽

Material Structure ◽

Average Particle ◽

Microcrystalline Silicon ◽

X Ray

AbstractExpanding thermal plasma CVD (ETP CVD) has been used to deposit thin microcrystalline silicon films. In this study we varied the position at which the silane is injected in the expanding hydrogen plasma: relatively far from the substrate and close to the plasma source, giving a long interaction time of the plasma with the silane, and close to the substrate, resulting in a short interaction time. The material structure is studied extensively. The crystalline fractions as obtained from Raman spectroscopy as well as from X-ray diffraction (XRD) vary from 0 to 67%. The average particle sizes vary from 6 to 17 nm as estimated from the (111) XRD peak using the Scherrer formula. Small angle X-ray scattering (SAXS) and flotation density measurements indicate void volume fractions of about 4 to 6%. When the samples are tilted the SAXS signal is lower than for the untilted case, indicating elongated objects parallel to the growth direction in the films. We show that the material properties are influenced by the position of silane injection in the reactor, indicating a change in the plasma chemistry.

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Discovery of recombining plasma inside the extended gamma-ray supernova remnant HB9

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2461 ◽

2019 ◽

Vol 489 (3) ◽

pp. 4300-4310 ◽

Cited By ~ 5

Author(s):

A Sezer ◽

T Ergin ◽

R Yamazaki ◽

H Sano ◽

Y Fukui

Keyword(s):

Supernova Remnant ◽

Gamma Ray ◽

Radio Continuum ◽

Continuum Emission ◽

Large Area ◽

Imaging Spectrometer ◽

X Ray ◽

East Region ◽

X Ray Imaging ◽

Collisional Ionization

ABSTRACT We present the results from the Suzaku X-ray Imaging Spectrometer observation of the mixed-morphology supernova remnant (SNR) HB9 (G160.9+2.6). We discovered recombining plasma (RP) in the western Suzaku observation region and the spectra here are well described by a model having collisional ionization equilibrium (CIE) and RP components. On the other hand, the X-ray spectra from the eastern Suzaku observation region are best reproduced by the CIE and non-equilibrium ionization model. We discuss possible scenarios to explain the origin of the RP emission based on the observational properties and concluded that the rarefaction scenario is a possible explanation for the existence of RP. In addition, the gamma-ray emission morphology and spectrum within the energy range of 0.2–300 GeV are investigated using 10 yr of data from the Fermi Large Area Telescope (LAT). The gamma-ray morphology of HB9 is best described by the spatial template of radio continuum emission. The spectrum is well fit to a log-parabola function and its detection significance was found to be 25σ. Moreover, a new gamma-ray point source located just outside the south-east region of the SNR’s shell was detected with a significance of 6σ. We also investigated the archival H i and CO data and detected an expanding shell structure in the velocity range of $-10.5$ and $+1.8$ km s−1 that is coinciding with a region of gamma-ray enhancement at the southern rim of the HB9 shell.

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