E-Print Archive

There are 4282 abstracts currently viewable.


Advanced Search
Main Page Add New E-Print Submitter
News Help/FAQ About Preferences
Manage Key Phrase
* News 04/04/20 * The archive is using a new backend database. This has thrown up a few SQL errors in the last few days. If you have any issues please email adavey@nso.edu with either the number of eprint you are trying to edit or a link to your preprint.

The Submillimeter Active Region Excess Brightness Temperature during Solar Cycles 23 and 24 View all abstracts by submitter

Guillermo Giménez de Castro   Submitted: 2020-09-08 19:51

We report the temporal evolution of the excess brightness temperature above solar active regions (ARs) observed with the Solar Submillimeter Telescope (SST) at 212 and 405 GHz during Cycles 23 and 24. Comparison with the sunspot number (SSN) yields a Pearson's correlation coefficient R=0.88 and 0.74 for 212 and 405 GHz, respectively. Moreover, when only Cycle 24 is taken into account the correlation coefficients go to 0.93 and 0.81 for each frequency. We derive the spectral index α between SST frequencies and found a slight anti-correlation with the SSN (R = -0.25); however, since the amplitude of the variation is lower than the standard deviation we cannot draw a definite conclusion. Indeed, α remains almost constant within the uncertainties with a median value of ~ 0 characteristic of an optically thick thermal source. Since the origin of the AR submillimeter radiation is thermal continuum produced at chromospheric heights, the strong correlation between the excess brightness temperature and the magnetic cycle evolution could be related to the available free magnetic energy to be released in reconnection events.

Authors: C. G. Giménez de Castro, A. L. Garcia Pereira, J.F. Valle Silva, C. L. Selhorst, C.H. Mandrini, G. D. Cristiani, J.-P. Raulin, A. Valio
Projects: None

Publication Status: Accepted to be published in The Astrophysical Journal
Last Modified: 2020-09-09 13:03
Go to main E-Print page  Helicity proxies from linear polarisation of solar active regions  Nanoflare Diagnostics from Magnetohydrodynamic Heating Profiles  Edit Entry  Download Preprint  Submitter's Homepage Delete Entry 

Go to main E-Print pageGo to main E-Print page.
Previous AbstractPrevious Abstract.
Next AbstractNext Abstract.
Download PreprintDownload Preprint.
Submitter's HomepageSubmitters Homepage.
Edit EntryEdit Entry.
View All Abstracts By SubmitterView all abstracts by submitter.
Delete AbstractDelete abstract.

Latest Entries
Propagation Effects in Quiet Sun Observations at Meter Wavelengths
Twin Null-Point-Associated Major Eruptive Three-Ribbon Flares with Unusual Microwave Spectra
Trajectory Determination for Coronal Ejecta Observed by WISPR/Parker Solar Probe
Recurring Homologous Solar Eruptions in NOAA AR 11429
Resonant absorption: transformation of compressive motions into vortical motion
The depth and the vertical extent of the energy deposition layer in a medium-class solar flare
Helicity proxies from linear polarisation of solar active regions
The Submillimeter Active Region Excess Brightness Temperature during Solar Cycles 23 and 24
Nanoflare Diagnostics from Magnetohydrodynamic Heating Profiles
The Solar Orbiter mission - Science Overview
Time Series Analysis of Photospheric Magnetic Parameters of Flare-quiet versus Flaring Active Regions: Scaling Properties of Fluctuations
Image Quality Assessment for Full-Disk Solar Observations with Generative Adversarial Networks
Identifying and Tracking Solar Magnetic Flux Elements with Deep Learning
Active Region Irradiance During Quiescent Periods: New Insights from Sun-as-a-star Spectra
Probing solar flare accelerated electron distributions with prospective X-ray polarimetry missions
Accelerating and Supersonic Density Fluctuations in Coronal Hole Plumes: Signature of Nascent Solar Winds
Sequential Lid Removal in a Triple-Decker Chain of CME-Producing Solar Eruptions
RESIK and RHESSI observations of the 20 September 2002 flare
Starspot mapping with adaptive parallel tempering I: Implementation of computational code
Heating and Eruption of a Solar Circular Ribbon Flare

Related Pages
MSU Solar Physics.
Max Millennium Science Mail Archive.
Max Millennium Message of the Day Mail Archive.
Max Millennium Flare Catalog

Archive Maintainer
Alisdair Davey

© 2000-2020 Solar Physics Group - Montana State University