SOTSP: HOP34
2007-08-28T10:08:00 to 2007-08-28T11:16:00
Science Goal: Active Region and; Network Wave Propagation: Active Region Movie
Program: Fast map 164 arcsec
Target: Active Region
xcen=191 ycen=-196
Instrument: SOTSP
HOP/JOP: 34
Description:
Daily Note and User Entry: EIS: Target of Opportunity observations of on-disk coronal hole. SOT: Support HOP 34 (AR network/waves) andnbsp
AR 10969 XRT: CCD Bakeout (if complete, obtain CCD spatial sensitivity calibration with G-Band and other X-ray thin filters
and then provide partial support for HOP 34). AOCS: a command will be issued to be back to D/N auto.
Request to SOT: SOT observations are requested, allowing simultaneous observations of the photospheric G-band and
Ca H intensity, Doppler velocity and vector magnetic field. HINODE/SOT Observables: High cadence BFI optical filtergrams full FOV - Ca II H, G-band, WL
Dopplergrams
SP maps 164"x164", 0.16" sampling.
Scientific Objectives: Intensity and velocity oscillations have been observed in the chromosphere above sunspots for over thirty years (Beckers and
Tallant 1969
Beckers and
Schultz 1972
Gurman et al. 1982
Lites et al. 1982). These oscillations have since been observed in the transition region, using space-based instruments observing in the extreme ultra-violet (EUV) (see, Fludra 2001
O'Shea et al. 2002
Rendtel et al. 2003
Brynildsen et al. 2004, and references within). Additionally, space-based EUV bandpass imagers have observed periodic intensity propagations along diffuse, fan-like, coronal loop structures (Berghmans and
Clette 99
Nightingale et al 1999, De Moortel 2002a). De Moortel (2002b) observe a relationship between 3-minute propagations found within sunspot coronal loops, and 5-minute propagations found within plage coronal loops. In Marsh et al.(2003) we present an observation of a 5-minute propagating wave within a plage coronal loop
the intensity oscillation of the wave was also observed simultaneously at transition region temperatures, suggesting wave propagation through the transition region into the corona along the active region loops. Depontieu et al. (2005) also discuss the possibility of channeling the 5-min photospheric oscillations into the corona along the magnetic field. The bright solar network, defined by the boundaries of supergranular flows, is dominated by magnetohydrodynamic (MHD) processes and contains oscillations with periods above of the acoustic cut-off (Goodman 2000). Regions of enhanced emission have the strongest magnetic fields and constitute the most intense radiative losses. The microstructure of these fields and their interactions with the convection zone supply energy to the overlying layers. The granular buffeting of flux tubes in the photosphere can create transverse waves which may mode couple to longitudinal waves and can be observed through variations in the plasma emission and radial velocity. In Marsh and
Walsh (2006) we present new, spatially resolved, monochromatic imaging data of a sunspot region at transition region temperatures, combined with simultaneous bandpass imaging of the emerging coronal loops. The 3-minute umbral oscillations are observed in the transition region, and are then observed to propagate along the sunspot coronal loop system. These propagating waves are interpreted as the transmission of global p-modes that undergo absorption, slow mode conversion, and are wave-guided into the corona by the strong magnetic field. A complete, simultaneous, view of the atmosphere from the photosphere, chromosphere, transition region and corona is required.
Other Instruments: SST TRACE
