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Jagan Ranganathan

Publications and source records attributed to Jagan Ranganathan.

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2023

Assembly of the FOXSI-4 Mirror Modules

The Focusing Optics X-ray Solar Imager 4 (FOXSI-4) is a heliophysics sounding rocket experiment that is currently in its fourth launch campaign. The payload is comprised of seven x-ray telescopes, which each consist of a 2 m focal length grazing incidence mirror module that focuses x-rays onto an imaging detector. For this fourth flight, Marshall Space Flight Center (MSFC) designed, built, and tested three new high-angular-resolution mirror module assemblies (MMAs). This paper describes the design and assembly of the FOXSI-4 MMAs.

FOXSI-4↗
NASA NTRS2023

Assembly of the FOXSI-4 Mirror Modules

The Focusing Optics X-ray Solar Imager 4 (FOXSI 4) is a heliophysics sounding rocket experiment that is currently in its fourth launch campaign. The payload is comprised of seven 2 m focal length X-ray telescopes, which each consist of a grazing incidence mirror module that focuses x-rays onto an imaging detector. For this fourth flight, Marshall Space Flight Center (MSFC) designed, built, and tested three new high-angular-resolution optics. This paper describes the design and assembly of the FOXSI 4 mirror modules.

Stephen D. Bongiorno↗
NASA NTRS2021

Assembly of the IXPE Mirror Modules

Expected to launch in December 2021, the Imaging X-ray Polarimetry Explorer (IXPE) is a NASA Astrophysics Small Explorer Mission with significant contributions from the Italian space agency (ASI). Three identical x-ray telescopes combine to form the IXPE Observatory. Each is comprised of a 4-m-focal length mirror module assembly (MMA, provided by Marshall Space Flight Center) that focuses x-rays onto a polarization-sensitive, imaging detector (contributed by ASI-funded institutions). This paper describes the now-completed assembly process for the 3 flight and one spare mirror modules, and compares as-tested calibrated performance with as-built metrology data. Unexpected challenges and lessons-learned are also discussed.

X-ray optics IXPE polarimetry↗
NASA NTRSDate not supplied

MaGIXS 2: Preparations for the Second Flight of the Marshall Grazing Incidence X-ray Spectrometer

Overview MaGIXS is a slitless soft X-ray (SXR) imaging spectrometer designed to observe solar active regions. - The instrument produces spatially resolved SXR spectra, known as “overlappograms.” (Athiray et al. 2019 & Champey et al., 2022) The first sounding rocket flight of the Marshall Grazing Incidence X-ray Spectrometer occurred on July 30, 2021 from the White Sands Missile Range, New Mexico. - Spectrally pure images of X-ray bright points were obtained through the inversion of overlappograms, e.g. Fig. 3 (Savage et al., 2022). MaGIXS 2 is a simplified version of the original design, less the spectrometer mirror pair. - Eliminating the spectrometer mirror pair improves spatial resolution, increases effective area and the field of view (Table 1). No field stop in this design, data will be an overlappogram with the same spatial and spectral plate scale.

x-ray spectrometer, x-ray optics, solar corona, so↗
NASA NTRSDate not supplied

An Overview of MaGIXS-2, The Second Flight of the Marshall Grazing Incidence X-ray Spectrometer

MaGIXS is a slitless soft X-ray (SXR) imaging spectrometer designed to observe solar active regions. - The instrument produces spatially resolved SXR spectra, known as “overlappograms.” (Athiray et al. 2019 & Champey et al., 2022) The first sounding rocket flight of the Marshall Grazing Incidence X-ray Spectrometer occurred on July 30, 2021 from the White Sands Missile Range, New Mexico. - Spectrally pure images of X-ray bright points were obtained through the inversion of overlappograms, e.g. Fig. 3 (Savage et al., 2022). MaGIXS 2 is a simplified version of the original design, less the spectrometer mirror pair. - Eliminating the spectrometer mirror pair improves spatial resolution, increases effective area and the field of view (Table 1). No field stop in this design, data will be an overlappogram with the same spatial and spectral plate scale.

x-ray spectrometer, x-ray optics, solar corona, so↗
NASA NTRSDate not supplied

An Overview of MaGIXS-2: The second flight of the Marshall Grazing Incidence X-ray Spectrometer

The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a sounding rocket mission that completed a successful flight from the White Sands Missile Range on July 30, 2021. MaGIXS captured spatially resolved soft X-ray spectra from portions of two solar active regions during its roughly 5-minute flight. The instrument was originally designed as a grazing incidence slit spectrograph but flew in a slit-less configuration that produced overlapping spectroheliograms. For the second flight, MaGIXS-2, the instrument has been reconfigured to a more simplified optical layout that reuses the Wolter-I telescope and blazed varied-line space reflective grating. The field stop at the telescope focal plane and the finite conjugate spectrometer mirror pair have been removed – the telescope now directly feeds the grating. Additionally, an identical but new 2k x 1k CCD camera has been built for this flight. The MaGIXS-2 data product will again be overlapping spectroheliograms of at least one solar active region, but with improved resolution, a larger field of view and increased effective area. Here we present the updated instrument layout, the expected performance, the integration and calibration approach, and proposed future improvements, including the implementation of additional complimentary spectral diagnostics.

Imaging Spectrometer↗