Joint AXAF high-resolution mirror assembly and AXAF CCD Imaging Spectrometer calibration at the MSFC X-Ray Calibration Facility

ABSTRACT RT Cru belongs to the rare class of hard X-ray emitting symbiotics, whose origin is not yet fully understood. In this work, we have conducted a detailed spectroscopic analysis of X-ray emission from RT Cru based on observations taken by the Chandra Observatory using the Low Energy Transmission Grating (LETG) on the High-Resolution Camera Spectrometer (HRC-S) in 2015 and the High Energy Transmission Grating (HETG) on the Advanced CCD Imaging Spectrometer S-array (ACIS-S) in 2005. Our thermal plasma modelling of the time-averaged HRC-S/LETG spectrum suggests a mean temperature of kT ∼ 1.3 keV, whereas kT ∼ 9.6 keV according to the time-averaged ACIS-S/HETG. The soft thermal plasma emission component (∼1.3 keV) found in the HRC-S is heavily obscured by dense materials (>5 × 1023 cm−2). The aperiodic variability seen in its light curves could be due to changes in either absorbing material covering the hard X-ray source or intrinsic emission mechanism in the inner layers of the accretion disc. To understand the variability, we extracted the spectra in the ‘low/hard’ and ‘high/soft’ spectral states, which indicated higher plasma temperatures in the low/hard states of both the ACIS-S and HRC-S. The source also has a fluorescent iron emission line at 6.4 keV, likely emitted from reflection off an accretion disc or dense absorber, which was twice as bright in the HRC-S epoch compared to the ACIS-S. The soft thermal component identified in the HRC-S might be an indication of a jet that deserves further evaluations using high-resolution imaging observations.

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In Search of X-rays from Uranus

10.5194/epsc2020-1028 ◽

2020 ◽

Author(s):

William Dunn ◽

Jan-Uwe Ness ◽

Laurent Lamy ◽

Grant Tremblay ◽

Graziella Branduard-Raymont ◽

...

Keyword(s):

High Resolution ◽

Solar Minimum ◽

Solar Maximum ◽

Field Of View ◽

X Rays ◽

Imaging Spectrometer ◽

Ccd Imaging ◽

X Ray ◽

Upper Limits ◽

Photon Energy Distribution

Within the solar system, X-ray emissions have been detected from every planet except the Ice Giants: Uranus and Neptune. Here, we present three Chandra X-ray Observations of Uranus (each 24-30 ks duration): an Advanced CCD Imaging Spectrometer (ACIS) observation during solar maximum on 7 August 2002 and two High Resolution Camera (HRC) observations during solar minimum on 11 and 12 November 2017. The ACIS observation from 2002 shows a low signal but statistically significant detection of X-rays from Uranus. The measured Uranus X-ray fluxes of 10-15-10-16 erg/cm2/s from this detection are consistent with upper limits and modelling predictions in previous work (Ness & Schmidt. 2000; Cravens et al. 2006). &#160;The photon energy distribution from this observation is consistent with an X-ray emission from charge exchange or scattering of solar photons, as observed for Jupiter and Saturn. The two HRC observations from 2017 constitute non-detections. For 11 Nov 2017, the X-ray emission coincident with Uranus&#8217; location is dimmer than 98% of the Field of View. 12 November 2017, was also a non-detection, but with tentative hints of planetary X-ray signatures: Uranus was 4 times brighter than the previous day, and brighter than 94% of the Field of View (1.6 standard deviations > Field of View mean). At this time, the Uranus coincident X-ray signature also exhibited timing variation distinct from the field of view. Further and longer observations will be required to better characterise the nature of the X-ray emissions from Uranus.

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F-55 a Novel High Resolution Tunable X-ray Fluorescence Imaging Spectrometer for Materials Analysis

Powder Diffraction ◽

10.1154/1.2754502 ◽

2007 ◽

Vol 22 (2) ◽

pp. 188-188

Author(s):

S. Seshadri ◽

M. Feser ◽

W. Yun

Keyword(s):

High Resolution ◽

Fluorescence Imaging ◽

Imaging Spectrometer ◽

Materials Analysis ◽

X Ray

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HREXI calibration facility: mapping out subpixel-level responses from high-resolution cadmium zinc telluride imaging x-ray detectors

Journal of Astronomical Telescopes Instruments and Systems ◽

10.1117/1.jatis.6.2.026002 ◽

2020 ◽

Vol 6 (02) ◽

pp. 1

Author(s):

Arkadip Basak ◽

Branden Allen ◽

Jaesub Hong ◽

Daniel P. Violette ◽

Jonathan Grindlay

Keyword(s):

High Resolution ◽

Cadmium Zinc Telluride ◽

Zinc Telluride ◽

X Ray ◽

Calibration Facility ◽

Cadmium Zinc

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Chandra observations of the planetary nebula IC 4593

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1024 ◽

2020 ◽

Vol 494 (3) ◽

pp. 3784-3789

Author(s):

J A Toalá ◽

M A Guerrero ◽

L Bianchi ◽

Y-H Chu ◽

O De Marco

Keyword(s):

Planetary Nebula ◽

Careful Analysis ◽

Central Star ◽

Stellar Atmosphere ◽

Hot Stars ◽

Imaging Spectrometer ◽

Ccd Imaging ◽

X Ray ◽

High Ionization ◽

Thin Plasma

ABSTRACT The Advanced CCD Imaging Spectrometer (ACIS-S) camera on board the Chandra X-ray Observatory has been used to discover a hot bubble in the planetary nebula (PN) IC 4593, the most distant PN detected by Chandra so far. The data are used to study the distribution of the X-ray-emitting gas in IC 4593 and to estimate its physical properties. The hot bubble has a radius of ∼2 arcsec and is found to be confined inside the optically bright innermost cavity of IC 4593. The X-ray emission is mostly consistent with that of an optically thin plasma with temperature kT ≈ 0.15 keV (or TX ≈ 1.7 × 106 K), electron density ne ≈ 15 cm−3, and intrinsic X-ray luminosity in the 0.3–1.5 keV energy range LX = 3.4 × 1030 erg s−1. A careful analysis of the distribution of hard (E >0.8 keV) photons in IC 4593 suggests the presence of X-ray emission from a point source likely associated with its central star (CSPN). If this was the case, its estimated X-ray luminosity would be LX, CSPN = 7 × 1029 erg s−1, fulfilling the log(LX, CSPN/Lbol) ≈ −7 relation for self-shocking winds in hot stars. The X-ray detection of the CSPN helps explain the presence of high-ionization species detected in the ultraviolet spectra as predicted by stellar atmosphere models.

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