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We present the result of near-infrared (near-IR) [Fe II] line mapping of the supernova remnant IC443 with the IRSF/SIRIUS, using the two narrow-band filters tuned for the [Fe II] 1.257 micron and [Fe II] 1.644 micron lines. Covering a large area of 3 0 x 35, our observations reveal that [Fe II] filamentary structures exist all over the remnant, not only in an ionic shock shell, but also in a molecular shock shell and a central region inside the shells. With the two [Fe II] lines, we performed corrections for dust extinction to derive the intrinsic line intensities. We also obtained the intensities of thermal emission from the warm dust associated with IC443, using the far- and mid-IR images taken with AKARI and Spitzer, respectively. As a result, we find that the [Fe II] line emission relative to the dust emission notably enhances in the inner central region. We discuss causes of the enhanced [Fe II] line emission, estimating the Fe+ and dust masses.
We report high precision transit photometry of GJ1214b in JHKs bands taken simultaneously with the SIRIUS camera on the IRSF 1.4m telescope at Sutherland, South Africa. Our MCMC analyses show that the observed planet-to-star radius ratios in JHKs ban ds are R_{rm p}/R_{rm s,J} = 0.11833 pm 0.00077, R_{rm p}/R_{rm s,H} = 0.11522 pm 0.00079, R_{rm p}/R_{rm s,Ks} = 0.11459 pm 0.00099, respectively. The radius ratios are well consistent with the previous studies by Bean et al. (2011) within 1sigma, while our result in Ks band is shallower than and inconsistent at 4sigma level with the previous measurements in the same band by Croll et al. (2011). We have no good explanation for this discrepancy at this point. Our overall results support a flat transmission spectrum in the observed bands, which can be explained by a water-dominated atmosphere or an atmosphere with extensive high-altitude clouds or haze. To solve the discrepancy of the radius ratios and to discriminate a definitive atmosphere model for GJ1214b in the future, further transit observations around Ks band would be especially important.
In the J, H, and Ks bands survey of the the Galactic Center region over an area of 2deg x 5deg, we have found many dark clouds, among which a distinguished chain of dark clouds can be identified with a quiescent CO cloud. The distances of the clouds is estimated to be 3.2-4.2 kpc, corresponding to the Norma arm by our new method to determine distance to dark clouds using the cumulative number of stars against J-Ks colors. Adopting these estimated distances, the size is about 70 pc in length and the total mass of the cloud is 6x10^4 M_solar. Three compact HII regions harbor in the cloud, indicating that star forming activities are going on at the cores of the quiescent CO cloud on the spiral arm.
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