skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: OBSERVATIONS OF THE INTERACTION OF ACOUSTIC WAVES AND SMALL-SCALE MAGNETIC FIELDS IN A QUIET SUN

Abstract

The effect of the magnetic field on photospheric intensity and velocity oscillations at the sites of small-scale magnetic fields (SMFs) in a quiet Sun near the solar disk center is studied. We use observations made by the G-band filter in the Solar Optical Telescope on board Hinode for intensity oscillations; Doppler velocity, magnetic field, and continuum intensity are derived from an Ni I photospheric absorption line at 6767.8 A using the Michelson Doppler Imager on board the Solar and Heliospheric Observatory. Our analysis shows that both the high-resolution intensity observed in the G band and velocity oscillations are influenced by the presence of a magnetic field. While intensity oscillations are suppressed at all frequencies in strong magnetic field regions compared to weak magnetic field regions, velocity oscillations show an enhancement of power in the frequency band 5.5-7 mHz. We find that there is a drop of 20%-30% in the p-mode power of velocity oscillations within the SMFs when compared to the regions surrounding them. Our findings indicate that the nature of the interaction of acoustic waves with the quiet Sun SMFs is similar to that of large-scale magnetic fields in active regions. We also report the first results of themore » center-to-limb variation of such effects using the observations of the quiet Sun from the Helioseismic and Magnetic Imager (HMI) aboard the Solar Dynamics Observatory (SDO). The independent verification of these interactions using SDO/HMI suggests that the velocity power drop of 20%-30% in p-modes is fairly constant across the solar disk.« less

Authors:
;  [1];  [2]
  1. Indian Institute of Astrophysics, Bangalore 560 034 (India)
  2. Applied Mathematics Department, University of Sheffield, Sheffield S3 7RH (United Kingdom)
Publication Date:
OSTI Identifier:
22004289
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 744; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABSORPTION; MAGNETIC FIELDS; MAGNETISM; PHOTOSPHERE; SOUND WAVES; SUN; TELESCOPES

Citation Formats

Chitta, Lakshmi Pradeep, Kariyappa, R, Jain, Rekha, and Jefferies, Stuart M., E-mail: pradeepch@iiap.res.in, E-mail: rkari@iiap.res.in, E-mail: R.Jain@sheffield.ac.uk, E-mail: stuartj@ifa.hawaii.edu. OBSERVATIONS OF THE INTERACTION OF ACOUSTIC WAVES AND SMALL-SCALE MAGNETIC FIELDS IN A QUIET SUN. United States: N. p., 2012. Web. doi:10.1088/0004-637X/744/2/98.
Chitta, Lakshmi Pradeep, Kariyappa, R, Jain, Rekha, & Jefferies, Stuart M., E-mail: pradeepch@iiap.res.in, E-mail: rkari@iiap.res.in, E-mail: R.Jain@sheffield.ac.uk, E-mail: stuartj@ifa.hawaii.edu. OBSERVATIONS OF THE INTERACTION OF ACOUSTIC WAVES AND SMALL-SCALE MAGNETIC FIELDS IN A QUIET SUN. United States. https://doi.org/10.1088/0004-637X/744/2/98
Chitta, Lakshmi Pradeep, Kariyappa, R, Jain, Rekha, and Jefferies, Stuart M., E-mail: pradeepch@iiap.res.in, E-mail: rkari@iiap.res.in, E-mail: R.Jain@sheffield.ac.uk, E-mail: stuartj@ifa.hawaii.edu. 2012. "OBSERVATIONS OF THE INTERACTION OF ACOUSTIC WAVES AND SMALL-SCALE MAGNETIC FIELDS IN A QUIET SUN". United States. https://doi.org/10.1088/0004-637X/744/2/98.
@article{osti_22004289,
title = {OBSERVATIONS OF THE INTERACTION OF ACOUSTIC WAVES AND SMALL-SCALE MAGNETIC FIELDS IN A QUIET SUN},
author = {Chitta, Lakshmi Pradeep and Kariyappa, R and Jain, Rekha and Jefferies, Stuart M., E-mail: pradeepch@iiap.res.in, E-mail: rkari@iiap.res.in, E-mail: R.Jain@sheffield.ac.uk, E-mail: stuartj@ifa.hawaii.edu},
abstractNote = {The effect of the magnetic field on photospheric intensity and velocity oscillations at the sites of small-scale magnetic fields (SMFs) in a quiet Sun near the solar disk center is studied. We use observations made by the G-band filter in the Solar Optical Telescope on board Hinode for intensity oscillations; Doppler velocity, magnetic field, and continuum intensity are derived from an Ni I photospheric absorption line at 6767.8 A using the Michelson Doppler Imager on board the Solar and Heliospheric Observatory. Our analysis shows that both the high-resolution intensity observed in the G band and velocity oscillations are influenced by the presence of a magnetic field. While intensity oscillations are suppressed at all frequencies in strong magnetic field regions compared to weak magnetic field regions, velocity oscillations show an enhancement of power in the frequency band 5.5-7 mHz. We find that there is a drop of 20%-30% in the p-mode power of velocity oscillations within the SMFs when compared to the regions surrounding them. Our findings indicate that the nature of the interaction of acoustic waves with the quiet Sun SMFs is similar to that of large-scale magnetic fields in active regions. We also report the first results of the center-to-limb variation of such effects using the observations of the quiet Sun from the Helioseismic and Magnetic Imager (HMI) aboard the Solar Dynamics Observatory (SDO). The independent verification of these interactions using SDO/HMI suggests that the velocity power drop of 20%-30% in p-modes is fairly constant across the solar disk.},
doi = {10.1088/0004-637X/744/2/98},
url = {https://www.osti.gov/biblio/22004289}, journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 744,
place = {United States},
year = {Tue Jan 10 00:00:00 EST 2012},
month = {Tue Jan 10 00:00:00 EST 2012}
}