E-Print Archive

There are 4172 abstracts currently viewable.


Search:

Advanced Search
Options
Main Page Add New E-Print Submitter
Information
Feedback
News Help/FAQ About Preferences
Manage Key Phrase
Notification
Observations of solar chromospheric oscillations at 3 mm with ALMA View all abstracts by submitter

Spiros Patsourakos   Submitted: 2019-12-17 10:14

We studied chromospheric oscillations using Atacama Large millimeter and sub-millimeter Array (ALMA) time-series of interferometric observations of the quiet Sun obtained at 3 mm with a 2-s cadence and a spatial resolution of a few arcsec. The same analysis, over the same fields of view and for the same intervals, was performed for simultaneous Atmospheric Imaging Assembly (AIA) image sequences in 1600 Å. Spatially-resolved chromospheric oscillations at 3 mm, with frequencies of 4.2 +- 1.7 mHz are observed in the quiet Sun, in both cell and network. The coherence length-scale of the oscillations is commensurate with the spatial resolution of our ALMA observations. Brightness-temperature fluctuations in individual pixels could reach up to a few hundred K, while the spatially averaged power spectral densities yield rms in the range ~ 55-75 K, i.e., up to ~ 1 % of the averaged brightness temperatures and exhibit a moderate increase towards the limb. For AIA 1600 A, the oscillation frequency is 3.7 +- 1.7 mHz. The relative rms is up to 6 % of the background intensity, with a weak increase towards disk center (cell, average). ALMA 3 mm time-series lag AIA 1600 Å by ~ 100 s, which corresponds to a formation-height difference of ~ 1200 km. The ALMA oscillations that we detected exhibit higher amplitudes than those derived from the lower (~ 10 arcsec) resolution observations at 3.5 mm by White et al. (2006). Chromospheric oscillations are, therefore, not fully resolved at the length-scale of the chromospheric network, and possibly not even at the spatial resolution of our ALMA observations. Any study of transient brightenings in the mm-domain should take into account the oscillations.

Authors: S. Patsourakos, C. A. Alissandrakis, A. Nindos, T. S. Bastian
Projects: ALMA

Publication Status: A&A, in press
Last Modified: 2019-12-18 10:01
Go to main E-Print page  Peculiar solar sources and geospace disturbances on 20-26 August 2018  Observations and 3D MHD Modeling of a Confined Helical Jet Launched by a Filament Eruption  Edit Entry  Download Preprint  Delete Entry 

Key
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
The Distribution of Time Delays Between Nanoflares in Magnetohydrodynamic Simulations
Data-driven MHD Simulation of the Formation and Initiation of a Large-scale Pre-flare Magnetic Flux Rope in Solar Active Region 12371
NVST observations of collision-induced apparent fan-shaped jets
Cosmic ray interactions in the solar atmosphere
A correlation in the waiting-time distributions of solar flares
Alternative Models of Zebra Patterns in the Event on June 21, 2011
Torsional slow-mode oscillations discovered in the magnetic free energy during solar flares
Particle acceleration in coalescent and squashed magnetic islands II. Particle-In-cell approach
The time step constraint in radiation hydrodynamics
Continuous Null-Point Magnetic Reconnection Builds Up a Torus Unstable Magnetic Flux Rope Triggering the X9.3 Flare in Solar Active Region~12673
A Comparison of Flare Forecasting Methods. IV. Evaluating Consecutive-Day Forecasting Patterns
The New 2018 Version of the Meudon Spectroheliograph
Longitudinal filament oscillations enhanced by two C-class flares
Spatio-temporal energy partitioning in a non-thermally dominated two-loop solar flare
Meteospace, a New Instrument for Solar Survey at the Calern Observatory
Correcting the effect of magnetic tongues on the tilt angle of bipolar active regions
Hi-C 2.1 Observations of Jetlet-like Events at Edges of Solar Magnetic Network Lanes
Fine-scale Explosive Energy Release at Sites of Prospective Magnetic Flux Cancellation in the Core of the Solar Active Region Observed by Hi-C 2.1, IRIS, and SDO
Remote coronal dimmings related to a circular-ribbon flare
Formation and Eruption of a Mini-sigmoid Originating in Coronal Hole

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



© 2003 Solar Physics Group - Montana State University