61 research outputs found
Hinode Calibration for Precise Image Co-alignment between SOT and XRT (November 2006 -- April 2007)
To understand the physical mechanisms for activity and heating in the solar
atmosphere, the magnetic coupling from the photosphere to the corona is an
important piece of information from the Hinode observations, and therefore
precise positional alignment is required among the data acquired by different
telescopes. The Hinode spacecraft and its onboard telescopes were developed to
allow us to investigate magnetic coupling with co-alignment accuracy better
than 1 arcsec. Using the Mercury transit observed on 8 November 2006 and
co-alignment measurements regularly performed on a weekly basis, we have
determined the information necessary for precise image co-alignment and have
confirmed that co-alignment better than 1 arcsec can be realized between Solar
Optical Telescope (SOT) and X-Ray Telescope (XRT) with our baseline
co-alignment method. This paper presents results from the calibration for
precise co-alignment of CCD images from SOT and XRT.Comment: 8 pages, 9 figures, accepted for publication in PASJ (Hinode Special
issue
Strongly Blueshifted Phenomena Observed with {\it Hinode}/EIS in the 2006 December 13 Solar Flare
We present a detailed examination of strongly blueshifted emission lines
observed with the EUV Imaging Spectrometer on board the {\it Hinode} satellite.
We found two kinds of blueshifted phenomenon associated with the X3.4 flare
that occurred on 2006 December 13. One was related to a plasmoid ejection seen
in soft X-rays. It was very bright in all the lines used for the observations.
The other was associated with the faint arc-shaped ejection seen in soft
X-rays. The soft X-ray ejection is thought to be an MHD fast-mode shock wave.
This is therefore the first spectroscopic observation of an MHD fast-mode shock
wave associated with a flare.Comment: 18 pages, 1 table, 6 figures. ApJ, accepte
Development of precision Wolter mirrors for future solar x-ray observations
Taro Sakao, Satoshi Matsuyama, Ayumi Kime, Takumi Goto, Akihiko Nishihara, Hiroki Nakamori, Kazuto Yamauchi, Yoshiki Kohmura, Akira Miyake, Hirokazu Hashizume, Tadakazu Maezawa, Yoshinori Suematsu, and Noriyuki Narukage "Development of precision Wolter mirrors for future solar x-ray observations", Proc. SPIE 9603, Optics for EUV, X-Ray, and Gamma-Ray Astronomy VII, 96030U (4 September 2015); https://doi.org/10.1117/12.2188905
Development of precision Wolter mirrors for solar x-ray observations
Taro Sakao, Satoshi Matsuyama, Takumi Goto, Jumpei Yamada, Shuhei Yasuda, Kazuto Yamauchi, Yoshiki Kohmura, Ayumi Kime, Akira Miyake, Tadakazu Maezawa, Hirokazu Hashizume, Yoshinori Suematsu, Noriyuki Narukage, and Shin-nosuke Ishikawa "Development of precision Wolter mirrors for solar x-ray observations", Proc. SPIE 10386, Advances in X-Ray/EUV Optics and Components XII, 103860E (23 August 2017); https://doi.org/10.1117/12.2273507
Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP)
Chromosphere, the transition layer of the sun is a region to switch to the magnetic pressure dominated from plasma pressure dominated, simultaneous observation of the detailed magnetic field measurement and plasma of dynamic phenomenon here is what is the frontier of the next solar physics. As This is a challenge that has just mentioned, even the next solar observation satellite plan SOLAR-C, in the experiments we had used a NASA sounding rocket for the first time in the SOLAR-C plan, will address the chromosphere-transition layer magnetic field measurement there. It is, is a Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) plan, the linear polarization of Lyman emission lines chromosphere-transition layer shoots (121.6nm) were detected in 0.1 percent of high accuracy, a new technique called Hanre effect I get the magnetic field information of chromosphere-transition layer. In Japan, the US and Europe joint observation in November 2012 as a rocket experiment is adopted to NASA this plan that full-scale start-up, start from assembly work is 2014 spring flight observation device, currently, it is where the alignment of the optical elements have been implemented. After this, it is planned to continue with the performance evaluation towards the observation implementation of summer 2015. In addition to once again explain the contents of the plan In this presentation, we report an overview of the entire development and preparation current status
Solar Lyman-Alpha Polarization Observation of the Chromosphere and Transition Region by the Sounding Rocket Experiment CLASP
We are planning an international rocket experiment Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is (2015 planned) that Lyman line (Ly(alpha) line) polarization spectroscopic observations from the sun. The purpose of this experiment, detected with high accuracy of the linear polarization of the Ly(alpha) lines to 0.1% by using a Hanle effect is to measure the magnetic field of the chromosphere-transition layer directly. For polarization photometric accuracy achieved that approx. 0.1% required for CLASP, it is necessary to realize the monitoring device with a high throughput. On the other hand, Ly(alpha) line (vacuum ultraviolet rays) have a sensitive characteristics that is absorbed by the material. We therefore set the optical system of the reflection system (transmission only the wavelength plate), each of the mirrors, subjected to high efficiency of the multilayer coating in accordance with the role. Primary mirror diameter of CLASP is about 30 cm, the amount of heat about 30,000 J is about 5 minutes of observation time is coming mainly in the visible light to the telescope. In addition, total flux of the sun visible light overwhelmingly large and about 200 000 times the Ly(alpha) line wavelength region. Therefore, in terms of thermal management and 0.1% of the photometric measurement accuracy achieved telescope, elimination of the visible light is essential. We therefore, has a high reflectivity (> 50%) in Ly line, visible light is a multilayer coating be kept to a low reflectance (<5%) (cold mirror coating) was applied to the primary mirror. On the other hand, the efficiency of the polarization analyzer required chromospheric magnetic field measurement (the amount of light) Conventional (magnesium fluoride has long been known as a material for vacuum ultraviolet (MgF2) manufactured ellipsometer; Rs = 22%) about increased to 2.5 times were high efficiency reflective polarizing element analysis. This device, Bridou et al. (2011) is proposed "that is coated with a thin film of the substrate MgF2 and SiO2 fused silica." As a result of the measurement, Rs = 54.5%, to achieve a Rp = 0.3%, high efficiency, of course, capable of taking out only about s-polarized light. Other reflective optical elements (the secondary mirror, the diffraction gratingcollector mirror), subjected to high-reflection coating of Al + MgF2 (reflectance of about 80%), less than 5% in the entire optical system by these (CCD Science was achieved a high throughput as a device for a vacuum ultraviolet ray of the entire system less than 5% (CCD of QE is not included)
Mapping Solar Magnetic Fields from the Photosphere to the Base of the Corona
Routine ultraviolet imaging of the Sun's upper atmosphere shows the
spectacular manifestation of solar activity; yet we remain blind to its main
driver, the magnetic field. Here we report unprecedented spectropolarimetric
observations of an active region plage and its surrounding enhanced network,
showing circular polarization in ultraviolet (Mg II & and Mn I) and
visible (Fe I) lines. We infer the longitudinal magnetic field from the
photosphere to the very upper chromosphere. At the top of the plage
chromosphere the field strengths reach more than 300 gauss, strongly correlated
with the Mg II line core intensity and the electron pressure. This unique
mapping shows how the magnetic field couples the different atmospheric layers
and reveals the magnetic origin of the heating in the plage chromosphere.Comment: 50 pages, 11 figures, 1 table, published in Science Advance
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