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Related papers: Temperature diagnostics of chromospheric fibrils

200 papers

We present temperature-dependent infrared spectroscopic studies of CaMnSb2, a proposed threedimensional topological material. The low plasma edge in the reflectivity spectrum and small Drude component in the optical conductivity indicate a…

Resistance thermometry provides a time-tested method for taking temperature measurements. However, fundamental limits to resistance-based approaches has produced considerable interest in developing photonic temperature sensors to leverage…

Optics · Physics 2015-08-06 Haitan Xu , Mohammad Hafezi , J. Fan , J. M. Taylor , G. F. Strouse , Zeeshan Ahmed

$Context$. The thermal structure of the penumbra below its visible surface (i.e., $\tau_5 \ge 1$) has important implications for our present understanding of sunspots and their penumbrae: their brightness and energy transport, mode…

Solar and Stellar Astrophysics · Physics 2017-05-24 J. M. Borrero , M. Franz , R. Schlichenmaier , M. Collados , A. Asensio Ramos

We present measurements of the H I spin temperatures (T_s) of the Cold Neutral Medium (CNM) towards radio sources that are closely aligned with stars for which published H_2 ortho-para temperatures (T_{01}) are available from UV…

Astrophysics · Physics 2007-05-23 Nirupam Roy , Jayaram N. Chengalur , Raghunathan Srianand

Sunspot chromospheres display vigorous oscillatory signature when observed in chromospheric diagnostics like the strong Ca II lines and H-alpha. New high-resolution sunspot observations from the Swedish 1-m Solar Telescope show the…

Solar and Stellar Astrophysics · Physics 2015-06-16 Luc Rouppe van der Voort , Jaime de la Cruz Rodriguez

Penumbral microjets are short-lived, fine-structured and bright jets that are generally observed in chromospheric imaging of the penumbra of sunspots. Here we investigate their potential transition region signature, by combining…

Solar and Stellar Astrophysics · Physics 2015-10-08 Gregal J. M. Vissers , Luc H. M. Rouppe van der Voort , Mats Carlsson

Various effective temperature scales have been proposed over the years. Despite much work and the high internal precision usually achieved, systematic differences of order 100 K (or more) among various scales are still present. We present…

Solar and Stellar Astrophysics · Physics 2010-04-07 L. Casagrande , I. Ramirez , J. Melendez , M. Bessell , M. Asplund

Future solar missions and ground-based telescopes aim to understand the magnetism of the solar chromosphere. We performed a supporting study in Quintero Noda et al. (2016) focused on the infrared Ca II 8542 A line and we concluded that is…

Solar and Stellar Astrophysics · Physics 2016-12-07 C. Quintero Noda , T. Shimizu , Y. Katsukawa , J. de la Cruz Rodriguez , M. Carlsson , T. Anan , T. Oba , K. Ichimoto , Y. Suematsu

Recent advances in observational performance and numerical simulations have revolutionised our understanding of the solar chromosphere. This concerns in particular the structure and dynamics on small spatial and temporal scales. As a…

Solar and Stellar Astrophysics · Physics 2009-12-01 Sven Wedemeyer-Böhm

In this paper results of new far-infrared and middle-infrared measurements (wavenumber range of 4000cm-1 - 100cm-1) in the range of the temperature from 300K to 8K of the CoFe2O4 ceramic are presented. The bands positions and their shapes…

Over the last two decades the uninterrupted, high-resolution observations of the Sun, from the excellent range of telescopes aboard many spacecraft complemented with observations from sophisticated ground-based telescopes have opened up a…

Solar and Stellar Astrophysics · Physics 2015-06-05 G. Tsiropoula , K. Tziotziou , I. Kontogiannis , M. S. Madjarska , J. G. Doyle , Y. Suematsu

The optical fiber Fabry-Perot interferometer (FPI) has been widely investigated as a potential temperature sensor. To function as a temperature sensor, the cavity of the FPI is typically constructed from either silica fibers or polymers.…

Applied Physics · Physics 2025-01-20 Dewen Duan , Zihao Zhao , Yi-Yuan Xie

Aims. To understand the morphology of the chromosphere in sunspot umbra. We investigate if the horizontal structures observed in the spectral core of the Ca II H line are ephemeral visuals caused by the shock dynamics of more stable…

Solar and Stellar Astrophysics · Physics 2015-02-11 V. M. J. Henriques , E. Scullion , M. Mathioudakis , D. Kiselman , P. T. Gallagher , F. P. Keenan

A strain-insensitive temperature sensor based on multimode interference using standard multimode fibers (MMFs) is proposed according to the comprehensive study of the characteristics of the MMFs. The temperature and strain dependences on…

Optical properties of single-crystal monoclinic CuO in the range 70 - 6000 \cm were studied at temperatures from 7 to 300 K. Normal reflection spectra were obtained from the (001) and (010) crystal faces thus giving for the first time…

Strongly Correlated Electrons · Physics 2009-10-31 A. B. Kuz'menko , D. van der Marel , P. J. M. van Bentum , E. A. Tishchenko , C. Presura , A. A. Bush

We discuss spectropolarimetric measurements of photospheric (Fe I 630.25 nm) and chromospheric (Ca II 854.21 nm) spectral lines. Our long-term goal is to diagnose properties of the magnetic field near the base of the corona. We compare…

Solar and Stellar Astrophysics · Physics 2015-05-14 P. G. Judge , A. Tritschler , H. Uitenbroek , G. Cauzzi , K. Reardon , A. de Wijn

The Mg I b$_2$ line at 5173 \r{A} is primarily magnetically sensitive to heights between the mid photosphere and the low chromosphere, a region that has not been sufficiently explored in the solar atmosphere but is crucial for understanding…

Solar and Stellar Astrophysics · Physics 2025-03-18 A. L. Siu-Tapia , L. R. Bellot Rubio , D. Orozco Suárez , R. Gafeira

Recent theoretical advances show that the temperature of a system in equilibriumcan be measured from static snapshots of its constituents' instantaneous configurations, withoutregard to their dynamics. We report the first measurements of…

Soft Condensed Matter · Physics 2009-11-10 Yilong Han , David G. Grier

Controlling polarisation directly at low temperature is crucial for development of optical spectroscopy techniques at sub-Kelvin temperatures, for example, in a hybrid scheme where light is fed into and collected in the cryostat by fibres…

Optics · Physics 2025-01-07 Thierry Chanelière , Alexei D. Chepelianskii

Observations show that the Cosmic Microwave Background (CMB) contains tiny variations at the 10^{-5} level around its black-body equilibrium temperature. The detection of these temperature fluctuations provides to modern Cosmology evidence…

Astrophysics · Physics 2015-06-24 Armando Bernui