Grant-in-Aid for Scientific Research(S)Science and Engineering (Mathematical and physical sciences)
Approach to understand the solar coronal and chromosphericheating — from Hinode, IRIS & CLASP to SOLAR-C

Saku Tsuneta(Japan Aerospace Exploration Agency, Institute of Space and AstronauticalScience, Director General)

Research Area Astrophysics, Solar Physics, Plasma Science
KeywordSun, International Cooperation, Satellite, Rocket, Plasma
Polarimeter) is our project using NASA’s soundingPurpose and Background of the Research
rocketfor making a precise measurement of theSince its launch in 2006, the Japanese solarlinearpolarizationof the Lyman-! line emitted
satellite Hinode has significantly contributed tofrom
thechromosphereand transition region. Its
solar physics. Specifically it has revealed thatmainaimistoinfer,
for the first time, themagneto-hydrodynamic waves and super-sonic jetsmagnetic
fieldsinthechromosphereand transition
happen in the solar chromosphere, ubiquitously.
The chromosphere is not only an intermediate layer region with the Hanle effect. We will develop thesmoothly connecting the photosphere and corona, CLASP instrument by the end of FY2014, andbut a site where those dynamics may play an launch it in 2015. Observations with CLASP will
important role in the chromospheric and coronal be coordinated with Hinode and IRIS.
heating. Such discoveries imply that the nextExpected Research Achievements andfrontier in solar physics lies in simultaneous
observations between the dynamics and magnetic S c i e n t i f i c S i g n i f i c a n c e structures in the chromosphere and transition Hinode, IRIS and CLASP give us a complementary
region, where the gas-dominant photosphere set of data, which certainly constitutes asignificant breakthrough in solar physics.
changes to the magnetic-dominant corona.
One major objective of the next solar satellite Specifically, such data are directly relevant for one
SOLAR-C, which is proposed to be launched in of the main SOLAR-C science objectives: theFY2019, is to determine 3D magnetic structures in magnetic coupling of the chromosphere (andthe solar atmosphere for clarifying the dynamics transition region) with the photosphere and corona.
and heating in the chromosphere and corona. In Significant development of the SOLAR-C project
this research, we will clarify the scientific objectives will be achieved by providing essential informationand the technical feasibilities for SOLAR-C, by in the following main issues: (1) specifications ofinvestigating the chromosphere and transition the instrument to measure chromosphericregion. This will be achieved by combining data magnetic fields, (2) achievable accuracy of thefrom state-of-art Hinode, with data provided by the chromospheric magnetic fields, and (3) detection ofwaves which can significantly contribute toup-coming IRIS and CLASP instruments.
chromospheric/coronal heating and solar-windResearch Methodsacceleration.
[Step1] Investigations through Hinode –Publications Relevant to the Project
IRIS joint observations.
IRIS (Interface Region Imaging Spectrograph) is ! “Small-Scale Jetlike Features in Penumbral
Chromospheres”, Katsukawa,Y. et al., ScienceNASA’s new solar satellite launched in June 2013.
318,1597 (2007)
It will make spectroscopic observations in the!
“PropagatingWaves along Spicules”, Okamoto,chromosphere and transition region, and give usJ.
etal.,
AstrophysicalJournal, 724, L24 (2011)
temperature, density and velocity diagnostics in!
“ChromosphericLyman-Alpha
Spectro-Polarisuch regions. Hinode will provide essential
meter(CLASP)”,
Kano,R.
etal.,
Proc. of SPIE
complementary information through precise
8443,84434F(2012)
magnetic field measurements in the photosphere.
Some of our researchers will stay at the IRIS  Te r m o f P r o j e c t  FY2013 - 2017
science operation center in US, and make Hinode –IRIS coordinated observations intensively and  B u d g e t A l l o c a t i o n  150,900 Thousand Yen
systematically in the early phase of the IRIS
Homepage Address and Other Contact
operation starting in the summer of 2013.
[Step2] Development of the CLASP instrument Information
http://hinode.nao.ac.jp/KakenS
CLASP (Chromospheric Lyman-Alpha Spectro-