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The XRT Synoptic Composite Image Archive (SCIA) is a storage and gallery of X-ray full-Sun images obtained through the synoptic program of the X-Ray Telescope (XRT) onboard the Hinode satellite. The archived images provide a quick history of solar activity through the daily and monthly layout pages and long-term data for morphological and quantitative studies of the X-ray corona. This article serves as an introduction to the SCIA, i.e., to the structure of the archive and specification of the data products included therein. We also describe a number of techniques used to improve the quality of the archived images: preparation of composite images to increase intensity dynamic range, removal of dark spots that are due to contaminants on the CCD, and correction of the visible stray light contamination that has been detected on the Ti-poly and C-poly filter images since May 2012.

We present coalignment calibration procedures for the X-ray Telescope (XRT) onboard the Hinode satellite. We performed not only an XRT stand-alone calibration, but also cross calibration using data from the Helioseismic and Magnetic Imager (HMI) and the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). Several new methods we describe here may also be useful for the coalignment calibration of other instruments. We have developed a database of coalignment coefficients and software to access it, so that all XRT images can be easily and accurately overlaid onto the images from other instruments, especially AIA and HMI.

We present the H$\alpha$ observations from ARIES, Nainital of a compact and impulsive solar flare occurred on March 10, 2001 and associated with a CME. We have also analysed HXT, SXT/Yohkoh observations as well as radio observations from Nobeyama Radio Observatory to derive the energetics and dynamics of this impulsive flare. We co-align the H$\alpha$, SXR, HXR, MW and magnetogram images within the instrumental spatial resolution limit. We detect a single HXR source in this flare, which is found spatially associated with one of the H$\alpha$ bright kernel. The unusual feature of HXR and H$\alpha$ sources, observed for the first time, is the rotation during the impulsive phase in clockwise direction. We propose that the rotation may be due to asymmetric progress of the magnetic reconnection site or may be due to the change of peak point of the electric field. In MW emission we found two sources, one is main source which is at the main flare site and another is remote source located in South-West direction. It appears that the remote source is formed by the impact of accelerated energetic electrons from the main flare site. From the spatial co-relation of multi-wavelength images of th, Comment: Accepted in Solar Physics, 20 pages, 12 Figures

The flare catalogue of the Yohkoh mission is compiled and linked to this article as an electronic supplement. For showing flare characteristics over wide energy range concisely, we provide the images of Hard X-ray Telescope (HXT) and the Soft X-ray Telescope (SXT), and the spectra of Hard X-ray Spectrometer (HXS) and Gamma-Ray Spectrometer (GRS) with the Wide Band Spectrometer (WBS) time profiles. The energy versus pulse height (PH) data channels in HXS and GRS are re-calibrated by using the data of the whole mission period. Secular gain changes are recognized in HXS, and the characteristics of power-law flare spectra simultaneously observed by HXT and HXS confirms the trend. The GRS gains are different for the flare observations during the previous maximum and for the current maximum. The total of 33 γ -ray events are observed, and for 12 of them γ-ray flare spectra are obtained.

We present the results of a detailed analysis of multi-wavelength observations of a very impulsive solar flare 1B/M6.7, which occurred on 10 March, 2001 in NOAA AR 9368 (N27 W42). The observations show that the flare is very impulsive with very hard spectrum in HXR that reveal non-thermal emission was most dominant. On the other hand this flare also produced type II radio burst and coronal mass ejections (CME), which are not general characteristics for impulsive flares. In H$\alpha$ we observed the bright mass ejecta (BME) followed by drak mass ejecta (DME). Based on the consistence of the onset times and direction of BME and CME, we conclude that these two phenomena are closely associated. It is inferred that the energy build-up took place due to photospheric reconnection between emerging positive parasitic polarity and predominant negative polarity, which resulted as a consequence of flux cancellation. The shear increased to $>80^o$ due to further emergence of positive parasitic polarity causing strongly enhanced cancellation of flux. It appears that such enhanced magnetic flux cancellation in a strongly sheared region triggered the impulsive flare., Comment: 14 pages, 8 Figures, Accepted for the publication in Solar Physics

Close correlations were found between Hα dark emerging loops and soft x-ray loop brightenings from five coordinated observations of emerging flux regions between the Soft X-ray Telescope (SXT) aboard Yohkoh satellite and the Domeless Solar Telescope (DST) of Hida Observatory. The results for the EFR of NOAA 7495 (4–5 May, 1993) are presented in some detail.

When magnetic flux emerges from beneath the photosphere it displaces the preexisting field in the corona, and a current sheet generally forms at the boundary between the old and new magnetic domains. Reconnection in the current sheet relaxes this highly stressed configuration to a lower energy state. This scenario is most familiar, and most often studied, in flares, where the flux transfer is rapid. We present here a study of steady, quiescent flux transfer occurring at a rate three orders of magnitude below that in a large flare. In particular we quantify the reconnection rate, and related energy release, occurring as new polarity emerges to form Active Region 11112 (2010-10-16T00:S18W14) within a region of preexisting flux. A bright, low lying kernel of coronal loops above the emerging polarity, observed with AIA onboard SDO and XRT onboard Hinode, originally shows magnetic connectivity only between regions of newly emerged flux when overlaid on magnetograms from HMI. Over the course of several days, this bright kernel advances into the preexisting flux. The advancement of an easily visible boundary into the old flux regions allows measurement of the rate of reconnection between old and new magnetic domains. We compare the reconnection rate to the inferred heating of the coronal plasma. To our knowledge, this is the first measurement of steady, quiescent heating related to reconnection. We determine that the newly emerged flux reconnects at a fairly steady rate of 0.38e16 Mx/s over two days, while the radiated power varies between 2~8e25 erg/s over the same time. We find that as much as 40% of the total emerged flux at any given time may have reconnected. The total amount of transferred flux (1e21 Mx) and radiated energy (7.2e30 ergs) are comparable to that of a large M- or small X-class flare, but are stretched out over 45 hours., Comment: 22 pages, 8 figures, accepted for publication in Solar Physics

The line-of-sight magnetograms from Solar Optical Telescope Narrowband Filter Imager observations of NOAA Active Region 10930 have been used to study the evolution of spinning and braiding helicities over a period of five days starting from 2006 December 9. The north (N) polarity sunspot was the follower and the south (S) polarity sunspot was the leader. The N-polarity sunspot in the active region was rotating in the counterclockwise direction. The rate of rotation was small during the first two days of observations and it increased up to 8°hr-1 on the third day of the observations. On the fourth and fifth days it remained at 4°hr-1 with small undulations in its magnitude. The sunspot rotated about 260° in the last three days. The S-polarity sunspot did not complete more than 20° in five days. However, it changed its direction of rotation five times over a period of five days and injected both the positive and negative type of spin helicity fluxes into the corona. Through the five days, both the positive and negative sunspot regions injected equal amounts of spin helicity. The total injected helicity is predominantly negative in sign. However, the sign of the spin and braiding helicity fluxes computed over all the regions were reversed from negative to positive five times during the five-day period of observations. The reversal in spinning helicity flux was found before the onset of the X3.4-class flare, too. Though, the rotating sunspot has been observed in this active region, the braiding helicity has contributed more to the total accumulated helicity than the spinning helicity. The accumulated helicity is in excess of -7 × 1043Mx2 over a period of five days. Before the X3.4-class flare that occurred on 2006 December 13, the rotation speed and spin helicity flux increased in the S-polarity sunspot. Before the flare, the total injected helicity was larger than -6 × 1043Mx2. The observed reversal in the sign of spinning and braiding helicity fluxes could be the signature of the emergence of a twisted flux tube, which acquires the writhe of an opposite sign. The magnetic cloud associated with the ejected mass has carried about -7 × 1041Mx2 of helicity. A time integration of helicity flux of about 1.2hr integrated backward in time of the observation of the coronal mass ejection is sufficient for this event. © 2011. The American Astronomical Society. All rights reserved. Fil: Ravindra, B.. Indian Institute Of Astrophysics; India Fil: Yoshimura, Keiji. Montana State University; Estados Unidos Fil: Dasso, Sergio Ricardo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina

Canon has developed an immersion exposure tool, the FPA-7000AS7 (AS7), with the industry's highest NA of 1.35. This paper reports on its performance. The AS7's projection lens achieves ultra-low aberration with total RMS of less than 5 mλ and flare of less than 0.5%. The resolution capability is 37 nm with k1 = 0.259, and DOF of 0.8 μm was obtained owing to the ultra-low aberration and low flare. Regarding focus performance, a 3σ value of 19.3 nm for Lstage and 16.1nm for R-stage were attained in a whole area. The result of CD uniformity of 1.91nm (3σ) was obtained across the wafer with a total of 4032 measurement points. Distortion was 3.9 nm at the worst value. On the other hand the most critical issue of immersion is defects, so the nozzle, lens and stage must be cleaned to reduce defects. The result of defect evaluation of the AS7 was an average of 0.042 defect/cm2 from 25 wafers in a lot and average 0.046 defect count/cm2 from long-term defect evaluation for two months. From these results, we are confident that the AS7 is capable of 45-nm node device production.

Candle-flame-shaped flares are archetypical structures that provide indirect evidence of magnetic reconnection. A flare resembling Tsuneta's famous 1992 candle-flame flare occurred on 2011 January 28; we present its temperature and electron density diagnostics. This flare was observed with Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA), Hinode/X-Ray Telescope (XRT), and Solar Terrestrial Relations Observatory Ahead (STEREO-A)/Extreme Ultraviolet Imager, resulting in high-resolution, broad temperature coverage, and stereoscopic views of this iconic structure. The high-temperature images reveal a brightening that grows in size to form a tower-like structure at the top of the posteruption flare arcade, a feature that has been observed in other long-duration events. Despite the extensive work on the standard reconnection scenario, there is no complete agreement among models regarding the nature of this high-intensity elongated structure. Electron density maps reveal that reconnected loops that are successively connected at their tops to the tower develop a density asymmetry of about a factor of two between the two legs, giving the appearance of half-loops. We calculate average temperatures with a new fast differential emission measure (DEM) method that uses SDO/AIA data and analyze the heating and cooling of salient features of the flare. Using STEREO observations, we show that the tower and the half-loop brightenings are not a line-of-sight projection effect of the type studied by Forbes & Acton. This conclusion opens the door for physics-based explanations of these puzzling, recurrent solar flare features, previously attributed to projection effects. We corroborate the results of our DEM analysis by comparing them with temperature analyses from Hinode/XRT.

We have been studying the spatial and temporal relations between Hα arch filament system (AFS) loops and soft X-ray (SXR) coronal loops, comparing high resolution Hα images of emerging flux regions (EFRs) observed with the Domeless Solar Telescope (DST) at Hida Obs. with SXR images taken by the Soft X-ray Telescope (SXT) aboard Yohkoh. The first results of this study were published in Kawai et al. (1992, 1993), showing good spatial correspondence between Hα AFS loops and SXR bright loops especially in the youngest parts of EFRs.