http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
UNNOTICED MAGNETIC FIELD OSCILLATIONS IN THE VERY QUIET SUN REVEALED BY SUNRISE/IMaX
Martí,nez Gonzá,lez, M. J.,Asensio Ramos, A.,Manso Sainz, R.,Khomenko, E.,Martí,nez Pillet, V.,Solanki, S. K.,Ló,pez Ariste, A.,Schmidt, W.,Barthol, P.,Gandorfer, A. IOP Publishing 2011 ASTROPHYSICAL JOURNAL LETTERS - Vol.730 No.2
<P>We present observational evidence for oscillations of magnetic flux density in the quiet areas of the Sun. The majority of magnetic fields on the solar surface have strengths of the order of or lower than the equipartition field (300-500 G). This results in a myriad of magnetic fields whose evolution is largely determined by the turbulent plasma motions. When granules evolve they squash the magnetic field lines together or pull them apart. Here, we report on the periodic deformation of the shapes of features in circular polarization observed at high resolution with SUNRISE. In particular, we note that the area of patches with a constant magnetic flux oscillates with time, which implies that the apparent magnetic field intensity oscillates in antiphase. The periods associated with this oscillatory pattern are compatible with the granular lifetime and change abruptly, which suggests that these oscillations might not correspond to characteristic oscillatory modes of magnetic structures, but to the forcing by granular motions. In one particular case, we find three patches around the same granule oscillating in phase, which means that the spatial coherence of these oscillations can reach 1600 km. Interestingly, the same kind of oscillatory phenomenon is also found in the upper photosphere.</P>
Guglielmino, S. L.,Martí,nez Pillet, V.,Bonet, J. A.,del Toro Iniesta, J. Carlos,Bellot Rubio, L. R.,Solanki, S. K.,Schmidt, W.,Gandorfer, A.,Barthol, P.,Knö,lker, M. IOP Publishing 2012 The Astrophysical journal Vol.745 No.2
<P>We report on the photospheric evolution of an intermediate-scale (approximate to 4 Mm footpoint separation) magnetic bipole, from emergence to decay, observed in the quiet Sun at high spatial (0 ''.3) and temporal (33 s) resolution. The observations were acquired by the Imaging Magnetograph Experiment imaging magnetograph during the first science flight of the Sunrise balloon-borne solar observatory. The bipole flux content is 6x10(17) Mx, representing a structure bridging the gap between granular scale bipoles and the smaller ephemeral regions. Footpoints separate at a speed of 3.5 km s(-1) and reach a maximum distance of 4.5 Mm before the field dissolves. The evolution of the bipole is revealed to be very dynamic: we found a proper motion of the bipole axis and detected a change of the azimuth angle of 90 degrees in 300 s, which may indicate the presence of some writhe in the emerging structure. The overall morphology and behavior are in agreement with previous analyses of bipolar structures emerging at the granular scale, but we also found several similarities with emerging flux structures at larger scales. The flux growth rate is 2.6 x 10(15) Mx s(-1), while the mean decay rate is one order of magnitude smaller. We describe in some detail the decay phase of the bipole footpoints that includes break up into smaller structures, and interaction with preexisting fields leading to cancellation, but it appears to be dominated by an as-yet unidentified diffusive process that removes most of the flux with an exponential flux decay curve. The diffusion constant (8 x 10(2) km(2) s(-1)) associated with this decay is similar to the values used to describe the large-scale diffusion in flux transport models.</P>
SUPERSONIC MAGNETIC UPFLOWS IN GRANULAR CELLS OBSERVED WITH SUNRISE/IMAX
Borrero, J. M.,Martí,nez-Pillet, V.,Schlichenmaier, R.,Solanki, S. K.,Bonet, J. A.,del Toro Iniesta, J. C.,Schmidt, W.,Barthol, P.,Gandorfer, A.,Domingo, V.,Knö,lker, M. IOP Publishing 2010 ASTROPHYSICAL JOURNAL LETTERS - Vol.723 No.2
Convectively Driven Sinks and Magnetic Fields in the Quiet-Sun
Requerey, Iker S.,Del Toro Iniesta, Jose Carlos,Rubio, Luis R. Bellot,Pillet, Valentí,n Martí,nez,Solanki, Sami K.,Schmidt, Wolfgang American Astronomical Society 2017 The Astrophysical journal Supplement series Vol.229 No.1
<P>We study the relation between mesogranular flows, convectively driven sinks and magnetic fields using high spatial resolution spectropolarimetric data acquired with the Imaging Magnetograph eXperiment on board SUNRISE. We obtain the horizontal velocity flow fields of two quiet-Sun regions (31.2 x 31.2 Mm(2)) via local correlation tracking. Mesogranular lanes and the central position of sinks are identified using Lagrange tracers. We find 6.7 x 10(-2) sinks per Mm(2) in the two observed regions. The sinks are located at the mesogranular vertices and turn out to be associated with (1) horizontal velocity flows converging to a central point and (2) long-lived downdrafts. The spatial distribution of magnetic fields in the quiet-Sun is also examined. The strongest magnetic fields are preferentially located at sinks. We find that 40% of the pixels with longitudinal components of the magnetic field stronger than 500 G are located in the close neighborhood of sinks. In contrast, the small-scale magnetic loops detected by Martinez Gonzalez et al. in the same two observed areas do not show any preferential distribution at mesogranular scales. The study of individual examples reveals that sinks can play an important role in the evolution of quiet-Sun magnetic features.</P>
MESOGRANULATION AND THE SOLAR SURFACE MAGNETIC FIELD DISTRIBUTION
Yelles Chaouche, L.,Moreno-Insertis, F.,Martí,nez Pillet, V.,Wiegelmann, T.,Bonet, J. A.,Knö,lker, M.,Bellot Rubio, L. R.,del Toro Iniesta, J. C.,Barthol, P.,Gandorfer, A.,Schmidt, W.,Solank IOP Publishing 2011 ASTROPHYSICAL JOURNAL LETTERS - Vol.727 No.2
SURFACE WAVES IN SOLAR GRANULATION OBSERVED WITH SUNRISE
Roth, M.,Franz, M.,Bello Gonzá,lez, N.,Martí,nez Pillet, V.,Bonet, J. A.,Gandorfer, A.,Barthol, P.,Solanki, S. K.,Berkefeld, T.,Schmidt, W.,del Toro Iniesta, J. C.,Domingo, V.,Knö,lker IOP Publishing 2010 ASTROPHYSICAL JOURNAL LETTERS - Vol.723 No.2
FULLY RESOLVED QUIET-SUN MAGNETIC FLUX TUBE OBSERVED WITH THE SUNRISE/IMAX INSTRUMENT
Lagg, A.,Solanki, S. K.,Riethmü,ller, T. L.,Martí,nez Pillet, V.,Schü,ssler, M.,Hirzberger, J.,Feller, A.,Borrero, J. M.,Schmidt, W.,del Toro Iniesta, J. C.,Bonet, J. A.,Barthol, P.,Berk IOP Publishing 2010 ASTROPHYSICAL JOURNAL LETTERS - Vol.723 No.2
Magnetic field emergence in mesogranular-sized exploding granules observed with sunrise/IMaX data
Palacios, J.,Blanco Rodrí,guez, J.,Vargas Domí,nguez, S.,Domingo, V.,Martí,nez Pillet, V.,Bonet, J. A.,Bellot Rubio, L. R.,Iniesta, J. C. del Toro,Solanki, S. K.,Barthol, P.,Gandorfe EDP Sciences 2012 Astronomy and astrophysics Vol.537 No.-
<P>We report on magnetic field emergences covering significant areas of exploding granules. The balloon-borne mission SUNRISE provided high spatial and temporal resolution images of the solar photosphere. Continuum images, longitudinal and transverse magnetic field maps and Dopplergrams obtained by IMaX onboard SUNRISE are analyzed by local correlation traking (LCT), divergence calculation and time slices, Stokes inversions and numerical simulations are also employed. We characterize two mesogranular-scale exploding granules where~10<SUP>18</SUP> Mx of magnetic flux emerges. The emergence of weak unipolar longitudinal fields (~100 G) start with a single visible magnetic polarity, occupying their respective granules’ top and following the granular splitting. After a while, mixed polarities start appearing, concentrated in downflow lanes. The events last around 20 min. LCT analyses confirm mesogranular scale expansion, displaying a similar pattern for all the physical properties, and divergence centers match between all of them. We found a similar behaviour with the emergence events in a numerical MHD simulation. Granule expansion velocities are around 1 kms<SUP>−1</SUP> while magnetic patches expand at 0.65 kms<SUP>−1</SUP>. One of the analyzed events evidences the emergence of a loop-like structure. Advection of the emerging magnetic flux features is dominated by convective motion resulting from the exploding granule due to the magnetic field frozen in the granular plasma. Intensification of the magnetic field occurs in the intergranular lanes, probably because of being directed by the downflowing plasma.</P>