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Flare Ribbons Approach Observed by the Interface Region Imaging Spectrograph and the Solar Dynamics Observatory
Hou, Yijun; Li, Ting; Zhang, Jun
We report flare ribbons approach (FRA) during a multiple-ribbon M-class flare on 2015 November 4 in NOAA AR 12443, obtained by the Interface Region Imaging Spectrograph and the Solar Dynamics Observatory. The flare consisted of a pair of main ribbons and two pairs of secondary ribbons. The two pairs of secondary ribbons were formed later than the …
Above the Noise: The Search for Periodicities in the Inner Heliosphere
De Moortel, Ineke; Threlfall, James; Conlon, Thomas
Remote sensing of coronal and heliospheric periodicities can provide vital insight into the local conditions and dynamics of the solar atmosphere. We seek to trace long (one hour or longer) periodic oscillatory signatures (previously identified above the limb in the corona by, e.g., Telloni et al. in Astrophys. J.767, 138, 2013) from their origin …
Removing Visual Bias in Filament Identification: A New Goodness-of-fit Measure
Green, C. -E.; Dawson, J. R.; Cunningham, M. R. +3 more
Different combinations of input parameters to filament identification algorithms, such as disperse and filfinder, produce numerous different output skeletons. The skeletons are a one-pixel-wide representation of the filamentary structure in the original input image. However, these output skeletons may not necessarily be a good representation of th…
Segmentation of photospheric magnetic elements corresponding to coronal features to understand the EUV and UV irradiance variability
Giono, G.; Zender, J. J.; Kariyappa, R. +5 more
Context. The magnetic field plays a dominant role in the solar irradiance variability. Determining the contribution of various magnetic features to this variability is important in the context of heliospheric studies and Sun-Earth connection.
Aims: We studied the solar irradiance variability and its association with the underlying magnetic fi…
M32 Analogs? A Population of Massive Ultra-compact Dwarf and Compact Elliptical Galaxies in Intermediate-redshift Clusters
Bell, Eric F.; Zhang, Yuanyuan
We report the discovery of relatively massive, M32-like ultra compact dwarf (UCD) and compact elliptical (CE) galaxy candidates in 0.2< z< 0.6 massive galaxy clusters imaged by the Cluster Lensing And Supernova survey with Hubble (CLASH) survey. Examining the nearly unresolved objects in the survey, we identify a sample of compact objects co…
Exploring the multifaceted circumstellar environment of the luminous blue variable HR Carinae
Umana, G.; Agliozzo, C.; Riggi, S. +9 more
We present a multiwavelength study of the Galactic luminous blue variable HR Carinae, based on new high-resolution mid-infrared (IR) and radio images obtained with the Very Large Telescope (VLT) and the Australia Telescope Compact Array (ATCA), which have been complemented by far-infrared Herschel-Photodetector Array Camera and Spectrometer (PACS)…
Chandra Detection of Intracluster X-Ray sources in Virgo
Liu, Chengze; Peng, Eric W.; Li, Zhiyuan +1 more
We present a survey of X-ray point sources in the nearest and dynamically young galaxy cluster, Virgo, using archival Chandra observations that sample the vicinity of 80 early-type member galaxies. The X-ray source populations at the outskirts of these galaxies are of particular interest. We detect a total of 1046 point sources (excluding galactic…
ALMA Observations of SMM11 Reveal an Extremely Young Protostar in Serpens Main Cluster
Ohashi, Nagayoshi; Tomisaka, Kohji; Yen, Hsi-Wei +8 more
We report the discovery of an extremely young protostar, SMM11, located in the associated submillimeter condensation in the Serpens Main cluster using the Atacama Large Millimeter/submillimeter Array (ALMA) during its Cycle 3 at 1.3 mm and an angular resolution of ∼ 0\buildrel{\prime\prime}\over{.} 5∼ 210 {AU}. SMM11 is a Class 0 protostar without…
Probing Subsurface Flows in NOAA Active Region 12192: Comparison with NOAA 10486
Hill, F.; Tripathy, S. C.; Jain, Kiran
NOAA Active Region (AR) 12192 is the biggest AR observed in solar cycle 24 so far. This was a long-lived AR that survived for four Carrington rotations (CRs) and exhibited several unusual phenomena. We measure the horizontal subsurface flows in this AR in multiple rotations using the ring-diagram technique of local helioseismology and the Global O…
A Spitzer Spectral Atlas of Low-mass Active Galactic Nuclei
Ho, Luis C.; Barth, Aaron J.; Greene, Jenny E. +1 more
We present Spitzer low-resolution Infrared Spectrograph (IRS) spectra (5 µm ≲ λ ≲ 40 µm) of a sample of 41 Type 1 and Type 2 active galactic nuclei (AGNs) with estimated black hole masses of {M}{BH} ≲ {10}6 {M}⊙ , in order to probe the validity of unification models in this mass regime. We find that the…