DISCOVERY OF UBIQUITOUS FAST-PROPAGATING INTENSITY DISTURBANCES BY THE CHROMOSPHERIC LYMAN ALPHA SPECTROPOLARIMETER (CLASP)

High cadence observations by the slit-jaw (SJ) optics system of the sounding rocket experiment known as the Chromospheric Lyman Alpha SpectroPolarimeter (CLASP) reveal ubiquitous intensity disturbances that recurrently propagate in one or both of the chromosphere or transition region at a speed much higher than the sound speed. The CLASP/SJ instrument provides a time series of 2D images taken with broadband filters centered on the Ly(alpha) line at a 0.6 s cadence. The fast propagating intensity disturbances are detected in the quiet Sun and in an active region, and at least 20 events are clearly detected in the field of view of 527 x 527 during the 5-minute observing time. The apparent speeds of the intensity disturbances range from 150 to 350 km/s, and they are comparable to the local Alfven speed in the transition region. The intensity disturbances tend to propagate along bright elongated structures away from areas with strong photospheric magnetic fields. This suggests that the observed propagating intensity disturbances are related to the magnetic canopy structures. The maximum distance traveled by the intensity disturbances is of about 10, and the widths are a few arcseconds, which is almost determined by the pixel size of 1.03. The timescale of each intensity pulse is shorter than 30 s. One possible explanation of the fast propagating intensity disturbances observed by CLASP is magneto-hydrodynamic fast mode waves.

[1]  Jonathan Cirtain,et al.  VUV testing of science cameras at MSFC: QE measurement of the CLASP flight cameras , 2015, SPIE Optical Engineering + Applications.

[2]  Search for High Velocities in the Disk Counterpart of Type II Spicules , 2008, 0804.3256.

[3]  W. Pesnell,et al.  The Solar Dynamics Observatory (SDO) , 2012 .

[4]  P. Judge,et al.  EVIDENCE FOR SHEET-LIKE ELEMENTARY STRUCTURES IN THE SUN'S ATMOSPHERE? , 2012 .

[5]  L. Golub,et al.  Prevalence of small-scale jets from the networks of the solar transition region and chromosphere , 2014, Science.

[6]  Jonathan Cirtain,et al.  Performance characterization of UV science cameras developed for the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) , 2014, Astronomical Telescopes and Instrumentation.

[7]  S. Toriumi,et al.  LIGHT BRIDGE IN A DEVELOPING ACTIVE REGION. II. NUMERICAL SIMULATION OF FLUX EMERGENCE AND LIGHT BRIDGE FORMATION , 2015, 1509.00205.

[8]  R. Harrison.  Euv Blinkers: The Significance of Variations in the Extreme Ultraviolet Quiet Sun , 1997 .

[9]  K. Shibata,et al.  NUMERICAL SIMULATION OF THREE-DIMENSIONAL ASYMMETRIC RECONNECTION AND APPLICATION TO A PHYSICAL MECHANISM OF PENUMBRAL MICROJETS , 2012 .

[10]  M. Carlsson,et al.  QUANTIFYING SPICULES , 2012, 1208.4404.

[11]  F. Auchère,et al.  ON THE FOURIER AND WAVELET ANALYSIS OF CORONAL TIME SERIES , 2016, 1606.05251.

[12]  H. Kurokawa,et al.  Short-Duration Active Region Brightenings Observed in the Extreme Ultraviolet and Hα by the Solar and Heliospheric Observatory Coronal Diagnostic Spectrometer and Hida Domeless Solar Telescope , 2004 .

[13]  R. Erdélyi,et al.  Observations of ubiquitous compressive waves in the Sun’s chromosphere , 2012, Nature Communications.

[14]  J. T. Hoeksema,et al.  The Helioseismic and Magnetic Imager (HMI) Investigation for the Solar Dynamics Observatory (SDO) , 2012 .

[15]  T. Kosugi,et al.  The Hinode (Solar-B) Mission: An Overview , 2007 .

[16]  R. Seguin,et al.  The Interface Region Imaging Spectrograph (IRIS) , 2012, 1401.2491.

[17]  V. Nakariakov,et al.  Magnetohydrodynamic waves and coronal seismology: an overview of recent results , 2012, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[18]  S. Cranmer,et al.  Statistical Study of Network Jets Observed in the Solar Transition Region: a Comparison Between Coronal Holes and Quiet-Sun Regions , 2016, 1604.06295.

[19]  C. J. Wolfson,et al.  The Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory (SDO) , 2011 .

[20]  L. R. V. D. Voort,et al.  Statistical properties of the Disk Counterparts of Type II Spicules from simultaneous observations of RBEs in Ca II 8542 and H{\alpha} , 2012, 1204.2943.

[21]  Yukio Katsukawa,et al.  Chromospheric Anemone Jets as Evidence of Ubiquitous Reconnection , 2007, Science.

[22]  S. Tsuneta,et al.  HINODE OBSERVATION OF THE MAGNETIC FIELDS IN A SUNSPOT LIGHT BRIDGE ACCOMPANIED BY LONG-LASTING CHROMOSPHERIC PLASMA EJECTIONS , 2009 .

[23]  Observing Cascades of Solar Bullets at High Resolution. II. , 2015 .

[24]  B. De Pontieu,et al.  ON THE TEMPORAL EVOLUTION OF THE DISK COUNTERPART OF TYPE II SPICULES IN THE QUIET SUN , 2012, 1212.4988.

[25]  A. Title,et al.  ON THE PENUMBRAL JETLIKE FEATURES AND CHROMOSPHERIC BOW SHOCKS , 2008 .

[26]  Bart De Pontieu,et al.  PROPAGATING WAVES ALONG SPICULES , 2011, 1106.4270.

[27]  Hirohisa Hara,et al.  Chromospheric Lyman-alpha spectro-polarimeter (CLASP) , 2012, Other Conferences.

[28]  Jiansen He,et al.  Upward propagating high-frequency Alfvén waves as identified from dynamic wave-like spicules observed by SOT on Hinode , 2009 .

[29]  A M Title,et al.  Small-Scale Jetlike Features in Penumbral Chromospheres , 2007, Science.

[30]  J. Sakai,et al.  Modeling Penumbral Microjets by Two-Fluid Simulations , 2008 .

[31]  I. Giagkiozis,et al.  Multiwavelength Studies of MHD Waves in the Solar Chromosphere , 2015, 1503.01769.

[32]  M. Carlsson,et al.  ON-DISK COUNTERPARTS OF TYPE II SPICULES IN THE Ca ii 854.2 nm AND Hα LINES , 2009, 0909.2115.

[33]  J. Beckers.  Solar spicules , 1968 .

[34]  B. Jurcevich,et al.  The Solar Optical Telescope for the Hinode Mission: An Overview , 2007, 0711.1715.

[35]  J. Leenaarts,et al.  Fan-shaped jets above the light bridge of a sunspot driven by reconnection , 2015, 1508.07927.

[36]  B. Pontieu,et al.  A Tale of Two Spicules: The Impact of Spicules on the Magnetic Chromosphere , 2007, 0710.2934.

[37]  H. Peter,et al.  Relation of transition region blinkers to the low chromosphere , 2003 .

[38]  S. Toriumi,et al.  LIGHT BRIDGE IN A DEVELOPING ACTIVE REGION. I. OBSERVATION OF LIGHT BRIDGE AND ITS DYNAMIC ACTIVITY PHENOMENA , 2015, 1509.00183.

[39]  Small-scale, Dynamic Bright Blobs in Solar Filaments and Active Regions , 2012, 1201.0406.

[40]  M. Carlsson,et al.  THE APPEARANCE OF SPICULES IN HIGH RESOLUTION OBSERVATIONS OF Ca ii H AND Hα , 2016, 1604.03116.

[41]  M. van Noort,et al.  High-resolution observations of fast events in the solar chromosphere , 2006 .