activity
20042023
most citedCRISP Spectropolarimetric Imaging of Penumbral Fine Structure

487 citations · 1.4k across the 18 of their papers we have counts for

collaborators

18 papers

astro-ph.IM2023

The 85-electrode AO system of the Swedish 1-m Solar Telescope

G. B. Scharmer, G. Sliepen, J. -C. Sinquin +3

We discuss the chosen concepts, detailed design, implementation and calibration of the 85-electrode adaptive optics (AO) system of the Swedish 1-meter Solar Telescope (SST), which…

astro-ph.IM2021★ 13 cited

Design and Performance Analysis of a Highly Efficient Polychromatic Full-Stokes Polarization Modulator for the CRISP Imaging Spectrometer

A. G. de Wijn, J. de la Cruz Rodríguez, G. B. Scharmer +2

We present the design and performance of a polychromatic polarization modulator for the CRisp Imaging SpectroPolarimeter (CRISP) Fabry-Perot tunable narrow-band imaging spectropola…

astro-ph.SR2020★ 22 cited

High-resolution observations of the solar photosphere, chromosphere and transition region. A database of coordinated IRIS and SST observations

L. H. M. Rouppe van der Voort, B. De Pontieu, M. Carlsson +30

NASA's Interface Region Imaging Spectrograph (IRIS) provides high resolution observations of the solar atmosphere through UV spectroscopy and imaging. Since the launch of IRIS in J…

astro-ph.IM2019★ 40 cited

Is the sky the limit? Performance of the revamped Swedish 1-m Solar Telescope and its blue- and red-beam re-imaging systems

Goran Scharmer, Mats Lofdahl, Guus Sliepen +1

We demonstrate that for data recorded with a solar telescope that uses adaptive optics and/or post-processing to compensate for many low- and high-order aberrations, the RMS granul…

astro-ph.SR2019★ 42 cited

Dissecting bombs and bursts: non-LTE inversions of low-atmosphere reconnection in SST and IRIS observations

G. J. M. Vissers, J. de la Cruz Rodriguez, T. Libbrecht +3

Ellerman bombs and UV bursts are transient brightenings that are ubiquitously observed in the lower atmospheres of active and emerging flux regions. Here we present inversion resul…

astro-ph.SR2019★ 7 cited

The dark side of penumbral microjets: Observations in Hα

D. Buehler, S. Esteban Pozuelo, J. de la Cruz Rodriguez +1

We present data of 10 penumbral microjets (PMJs) observed in Hα, Ca II 8542 Å, and Fe I 6302 Åline pair with the Swedish 1 m Solar Telescope (SST) with CRISP and Ca II K with SST/C…

astro-ph.IM2018★ 86 cited

SSTRED: Data- and metadata-processing pipeline for CHROMIS and CRISP

M. G. Löfdahl, T. Hillberg, J. de la Cruz Rodriguez +5

Context: Data from ground-based, high-resolution solar telescopes can only be used for science with calibrations and processing, which requires detailed knowledge about the instrum…

astro-ph.SR2017★ 91 cited

Intermittent reconnection and plasmoids in UV bursts in the low solar atmosphere

L. Rouppe van der Voort, B. De Pontieu, G. B. Scharmer +9

Magnetic reconnection is thought to drive a wide variety of dynamic phenomena in the solar atmosphere. Yet the detailed physical mechanisms driving reconnection are difficult to di…

astro-ph.SR2013★ 2 cited

Response to "Stray-light correction in 2D spectroscopy" by R. Schlichenmaier and M. Franz

G. B. Scharmer

We discuss a recent paper by Schlichenmaier & Franz (SF; 2013, A&A, 555, A84), in which the claim is made that the penumbral dark downflows detected for the first time with the Swe…

astro-ph.IM2011★ 15 cited

Sources of straylight in the post-focus imaging instrumentation of the Swedish 1-m Solar Telescope

M. G. Löfdahl, G. B. Scharmer

Recently measured straylight PSFs in Hinode/SOT make granulation contrast in observed data and synthetic MHD data consistent. Data from earthbound telescopes also need accurate cor…

astro-ph.SR2011★ 21 cited

SST/CRISP Observations of Convective Flows in a Sunspot Penumbra

G. B. Scharmer, V. M. J. Henriques

Context. Recent discoveries of intensity correlated downflows in the interior of a sunspot penumbra provide direct evidence for overturning convection, adding to earlier strong ind…

astro-ph.SR2010★ 26 cited

Striation and convection in penumbral filaments

H. C. Spruit, G. B. Scharmer, M. G. Löfdahl

Observations with the 1-m Swedish Solar Telescope of the flows seen in penumbral filaments are presented. Time sequences of bright filaments show overturning motions strikingly sim…

astro-ph.SR2010★ 43 cited

Small-scale convection signatures associated with strong plage solar magnetic field

G. Narayan, G. B. Scharmer

In this work, we study and quantify properties of strong-field small-scale convection and compare observed properties with those predicted by numerical simulations. We analyze spec…

astro-ph.IM2010★ 36 cited

High-order aberration compensation with Multi-frame Blind Deconvolution and Phase Diversity image restoration techniques

G. B. Scharmer, M. G. Löfdahl, T. I. M. van Werkhoven +1

Context. For accurately measuring intensities and determining magnetic field strengths of small-scale solar (magnetic) structure, knowledge of and compensation for the point spread…

astro-ph.IM2010★ 58 cited

S-DIMM+ height characterization of day-time seeing using solar granulation

G. B. Scharmer, T. I. M. van Werkhoven

To evaluate site quality and to develop multi-conjugative adaptive optics systems for future large solar telescopes, characterization of contributions to seeing from heights up to…

astro-ph2008★ 487 cited

CRISP Spectropolarimetric Imaging of Penumbral Fine Structure

G. B. Scharmer, G. Narayan, T. Hillberg +6

We discuss penumbral fine structure in a small part of a pore, observed with the CRISP imaging spectropolarimeter at the Swedish 1-m Solar Telescope (SST), close to its diffraction…

astro-ph2005★ 158 cited

Fine structure, magnetic field and heating of sunspot penumbrae

H. C. Spruit, G. B. Scharmer

We interpret penumbral filaments as due to convection in field-free, radially aligned gaps just below the visible surface of the penumbra, intruding into a nearly potential field a…

astro-ph2004★ 205 cited

Observational manifestations of solar magneto-convection -- center-to-limb variation

Mats Carlsson, Robert F. Stein, Ake Nordlund +1

We present the first center-to-limb G-band images synthesized from high resolution simulations of solar magneto-convection. Towards the limb the simulations show "hilly" granulatio…