A5048198842- Solar and Space Plasma Dynamics
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Solar Radiation and Photovoltaics
- Geomagnetism and Paleomagnetism Studies
- Ionosphere and magnetosphere dynamics
- Atmospheric Ozone and Climate
- Geophysics and Gravity Measurements
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Calibration and Measurement Techniques
- Dark Matter and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- History and Developments in Astronomy
- Climate variability and models
- Geology and Paleoclimatology Research
- Cosmology and Gravitation Theories
- Photorefractive and Nonlinear Optics
- Historical Astronomy and Related Studies
- Planetary Science and Exploration
- Particle Detector Development and Performance
- Inertial Sensor and Navigation
- Atmospheric and Environmental Gas Dynamics
- Impact of Light on Environment and Health
Max Planck Institute for Solar System Research
2016-2025
Kyung Hee University
2015-2024
Savitribai Phule Pune University
2024
Kamineni Institute of Dental Sciences
2024
Sri Sivasubramaniya Nadar College of Engineering
2014-2021
Max Planck Society
2011-2020
Japan Aerospace Exploration Agency
2010-2020
The University of Tokyo
2020
University of California, Irvine
2019
Collège de France
2019
Hypothetical low-mass particles, such as axions, provide a compelling explanation for the dark matter in universe. Such particles are expected to emerge abundantly from hot interior of stars. To test this prediction, CERN Axion Solar Telescope (CAST) uses 9 T refurbished Large Hadron Collider magnet directed towards Sun. In strong magnetic field, solar axions can be converted X-ray photons which recorded by detectors. 2013–2015 run, thanks low-background detectors and new telescope,...
Solar Orbiter, the first mission of ESA's Cosmic Vision 2015-2025 programme and a international collaboration between ESA NASA, will explore Sun heliosphere from close up out ecliptic plane. It was launched on 10 February 2020 04:03 UTC Cape Canaveral aims to address key questions solar heliospheric physics pertaining how creates controls Heliosphere, why activity changes with time. To answer these, carries six remote-sensing instruments observe corona, four in-situ measure wind, energetic...
Abstract. Simulations of climate over the Last Millennium (850–1850 CE) have been incorporated into third phase Paleoclimate Modelling Intercomparison Project (PMIP3). The drivers this period are chiefly orbital, solar, volcanic, changes in land use/land cover and some variation greenhouse gas levels. While these effects can be easily defined, reconstructions volcanic use-related forcing more uncertain. We describe here approach taken defining scenarios used PMIP3, document discuss likely...
Aims.Using a reconstruction of sunspot numbers stretching over multiple millennia, we analyze the statistics occurrence grand minima and maxima set new observational constraints on long-term solar stellar dynamo models.
Aims. We present a physically consistent reconstruction of the total solar irradiance for Holocene. Methods. extend SATIRE models to estimate evolution (and partly spectral) over The basic assumption is that variations are due dark and bright magnetic features on surface. decadally averaged flux computed from decadal values cosmogenic isotope concentrations recorded in natural archives employing series physics-based connecting processes modulation cosmic ray heliosphere their record...
Abstract. A long-standing task in climate research has been to distinguish between anthropogenic change and natural variability. prerequisite for fulfilling this is the understanding of relative roles external drivers internal variability carbon cycle. Here, we present first ensemble simulations over last 1200 years with a comprehensive Earth system model including fully interactive Applying up-to-date reconstructions forcing recent low-amplitude estimates solar variations, reproduce...
The lack of long and reliable time series solar spectral irradiance (SSI) measurements makes an accurate quantification contributions to recent climate change difficult. Whereas earlier SSI observations models provided a qualitatively consistent picture the variability, by SORCE satellite suggest significantly stronger variability in ultraviolet (UV) range changes visible near-infrared (NIR) bands anti-phase with cycle. A number chemistry-climate model (CCM) simulations have shown that this...
The brightness of the Sun varies on all timescales which it has been observed, and there is increasing evidence that this an influence climate. amplitudes such variations depend wavelength possibly timescale. Although many aspects variability are well established, exact magnitude secular (going beyond a solar cycle) spectral dependence under discussion. main drivers thought to be magnetic features at surface. climate response can be, global scale, largely accounted for by simple energetic...
Context.Total solar irradiance changes by about 0.1% between activity maximum and minimum. Accurate measurements of this quantity are only available since 1978 do not provide information on longer-term secular trends.
Abstract. The pre-industrial millennium is among the periods selected by Paleoclimate Model Intercomparison Project (PMIP) for experiments contributing to sixth phase of Coupled (CMIP6) and fourth PMIP (PMIP4). past1000 transient simulations serve investigate response (mainly) natural forcing under background conditions not too different from today, discriminate between forced internally generated variability on interannual centennial timescales. This paper describes motivation experimental...
Abstract. We update the forcings for PMIP3 experiments Last Millennium to include new assessments of historical land use changes and discuss suggestions calibrating solar activity proxies total irradiance.
The Sunrise balloon-borne solar observatory consists of a 1m aperture Gregory telescope, UV filter imager, an imaging vector polarimeter, image stabilization system and further infrastructure. first science flight yielded high-quality data that reveal the structure, dynamics evolution convection, oscillations magnetic fields at resolution around 100 km in quiet Sun. After brief description instruments data, qualitative results are presented. In contrast to earlier observations, we clearly...
This paper describes the Polarimetric and Helioseismic Imager on Solar Orbiter mission (SO/PHI), first magnetograph helioseismology instrument to observe Sun from outside Sun-Earth line. It is key meant address top-level science question: How does solar dynamo work drive connections between heliosphere? SO/PHI will also play an important role in answering other questions of Orbiter, as well hosting potential a rich return further science. measures Zeeman effect Doppler shift FeI 617.3nm...
Metis is the first solar coronagraph designed for a space mission capable of performing simultaneous imaging off-limb corona in both visible and UV light. The observations obtained with aboard Solar Orbiter ESA-NASA observatory will enable us to diagnose, unprecedented temporal coverage spatial resolution, structures dynamics full from 1.7 $R_\odot$ about 9 $R_\odot$. Due uniqueness profile, be able observe close vantage point (down 0.28 AU), achieving out-of-ecliptic views increase orbit...
Abstract Study Analysis Group 21 (SAG21) of NASA’s Exoplanet Exploration Program was organized to study the effect stellar contamination on space-based transmission spectroscopy, a method for studying exoplanetary atmospheres by measuring wavelength-dependent radius planet as it transits its star. Transmission spectroscopy relies precise understanding spectrum star being occulted. However, stars are not homogeneous, constant light sources but have temporally evolving photospheres and...
A model of solar irradiance variations is presented which based on the assumption that surface magnetism responsible for all total changes time scales days to years. series daily magnetograms and empirical models thermal structure magnetic features (sunspots, faculae) are combined reconstruct (and spectral) from 1996 2002. Comparisons with observational data reveal an excellent correspondence, although only contains a single free parameter. This provides strong support hypothesis caused by...
Asteroseismology provides us with the possibility of determining angle, i, between direction rotation axis a pulsating Sun-like star and line sight. A knowledge i is important not just for obtaining improved stellar parameters, but also in order to determine true masses extrasolar planets detected from radial velocity shifts their central stars. By means Monte Carlo simulations, we estimate precision measurement other parameters. We find that inclination angle can be retrieved accurately...