On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∼ 1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40 − 8 + 8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 M ⊙ . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∼ 40 Mpc ) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∼ 9 and ∼ 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.

A novel process-insensitive thermal protection structure has been developed. This circuit contains several sub-circuits such as band-gap reference, reference output buffer, resistance voltage divider branch, and hysteresis circuit. By using reference buffer, the precise reference voltage from band-gap reference is delivered to resistance voltage divider branch and is divided precisely. Then the threshold temperatures of this protection circuit can be set by this precise voltage, unaffected by process variation and mismatch. A hysteresis circuit is also used here to prevent thermal oscillation. This circuit is fabricated in TSMC 0.18 m CMOS technology, and occupies about 3 10 4 m 2 chip area.

Preliminary analysis is presented for J, H, and K 0 images of the Corona Australis cloud core. Color-color and color-magnitude diagrams reveal relatively few new cluster members. We conclude that the R Cr A infrared cluster consists of only about 30 members and its size re ects the available reservoir of molecular gas. Subject headings: star formation { R Coronae Australis { 3 {As shown in Fig. 5, there are 5 association members which lie below the reddening line 2 In addition to the 20 association members in the color-color diagram, we add IRS7, new K band excess sources IRS3, 18589-37035, and 18583-37046, two nebulous objects 18587-36584 and 18587-37046, and HD176386b (see Tables 1 and 2).

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We derive a new peak lag vs. peak luminosity relation in gamma-ray burst (GRB) pulses. We demonstrate conclusively that GRB spectral lags are pulse rather than burst properties and show how the lag vs. luminosity relation determined from CCF measurements of burst properties is essentially just a rough measure of this newly derived relation for individual pulses. We further show that most GRB pulses have correlated properties: short-lag pulses have shorter durations, are more luminous, and are harder within a burst than long-lag pulses. We also uncover a new pulse duration vs. pulse peak luminosity relation, and indicate that long-lag pulses often precede short-lag pulses. Although most pulse behaviors are supportive of internal shocks (including long-lag pulses), we identify some pulse shapes that could result from external shocks.