검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 655

        383.
        1998.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The structure and environments of the molecular clouds near the SNR HB3(G132.7±1.3) HB3(G132.7±1.3) are studied. The molecular complex which is located at the southern rim of HB3 was proposed by former investigators as the one interacting with HB3. This complex region of 2∘×2∘atl=133∘ 2∘×2∘atl=133∘ has been observed at 12CO,13CO,J=1−0ata1′ 12CO,13CO,J=1−0ata1′ , resolution with the 14-m radio telescope at Taeduk Radio Astronomy Observatory. We have reached to the following four conclusions. The possibility that these molecular complex and HB3 are interacting with each other cannot be supported with any of our data. The morphologies of the two show no similarities. Neither particular features for the interaction are found in the CO lines. The hypothetical 'Molecular wall' which was expected to exist on the northwestern rim of HB3 as a cause for the noncircular morphology of HB3 is turned out to be nonexistent in CO. The molecular complex which resembles a 'bar' at a low resolution is now resolved into a U-shaped shell. It seems that the U-shape is consist of two independent components. No peculiarities, such as unseen masses or bright stars capable of forming HlI regions, are found within the U-shape region. The total mass included in the complex is estimated to be Mtotal=2.9\~8.4×105M⨀ Mtotal=2.9\~8.4×105M⨀ , which is in good agreement with previous observations within errors. Considering about 12 clumps distinguishable within the complex, the total mass implies that masses of each of clumps are on the order of 104M⨀ 104M⨀ , which makes these good objects for further studies in relation to star-formation. Especially the clumps associated with W3 are worthy for more high resolution observations for better understanding of astrophysical phenomenon ongoing in them.
        5,200원
        384.
        1998.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Observations of the J=1-0 transition line of HCN were made at the center of Comet C/1995 O1 (Hale-Bopp) from November, 1996 to April, 1997 with the 14-m radio telescope at the TRAO (Taeduk Radio Astronomical Observatory). From the obtained data, an HCN production rate at each observed date was derived. The rapid variation of the HCN production rate near the perihelion was detected, and it is thought to be caused by jet(s) from the nucleus. The correlation between the visual magnitude and the HCN production rate is found to be QHCN=27.03−0.11(mv−5logΔ) QHCN=27.03−0.11(mv−5logΔ) .
        4,000원
        385.
        1998.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We present the development of a remote observation system runnig on world wide web (WWW). The system consists of a 30cm Schmidt Cassegrain telescope and ST-7 CCD camera. We built the controllers and drivers of the telescope and the control softwares including the network control. The self-developed techniques in the hard wares and softwares can be applied to other projects in Korea. Observers can access the system via WWW home page, to reserve observation times, to send control commands, to retrieve images and various information useful for observation. This system can be widely used by students and amateur astronomers as well as professional astronomers who need a lot of small telescope time.
        4,000원
        386.
        1998.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We have developed solar observational system in the department of Astronomy & Space Sciences of KyungHee University, in order to monitor solar activities and construct solar database for space weather forecasting at maximum of 23rd solar cycle, as well as an solar education and exercise for undergraduate students. Our solar observational system consists of the full disk monitoring system and the regional observation system for H a fine structure. Full disk monitoring system is made of an energy rejection filter, 16cm refractor, video CCD camera and monitor. Monitored data are recorded to VHS video tape and analog output of video CCD can be captured as digital images by the computer with video graphic card. Another system for regional observation of the sun is made of energy rejection filter, 21cm Schmidt-Cassegrain reflector, H a filter with 1.6A pass band width and 375×242 375×242 CCD camera. We can observe H a fine structure in active regions of solar disk and solar limb, by using this system. We have carried out intense solar observations for a test of our system. It is found that Quality of our H a image is as good as that of solar images provided by Space Environmental Center. In this paper, we introduce the basic characteristics of the KyungHee Solar Observation System and result of our solar observations. We hope that our data should be used for space weather forecasting with domestic data of RRL(Radio Research Laboratory) and SOFT(SOlar Flare Telescope).
        4,900원
        387.
        1998.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To study kinematics of solar prominences, we have made Ha spectrographic study of an eruptive prominence which appeared on the 27th of August, 1992 with a position angle of 270 deg. The observation was carried out by a Littrow type spectrograph and a G1 CCD camera attached to the 25cm coronagraph at Norikura Coronal Station. In taking the spectral data the slit was placed in parallel to the solar limb at 7 different heights, each being separated by 5 arcsec with a time step of 30 sec. The observed eruptive prominence shows a wide range of line of sight Doppler velocity, spanning from Vdopp=−17.5km/stoVdopp=58.2km/s Vdopp=−17.5km/stoVdopp=58.2km/s . It is also found that the velocity increases with height at the rate of ΔV=0.86km/s/arcsec ΔV=0.86km/s/arcsec .
        4,600원
        388.
        1998.10 구독 인증기관·개인회원 무료
        392.
        1998.10 구독 인증기관·개인회원 무료
        393.
        1998.10 구독 인증기관·개인회원 무료
        394.
        1998.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        4,000원
        395.
        1998.06 KCI 등재 구독 인증기관·개인회원 무료
        396.
        1997.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We carried out high-resolution(FWHM=3' .3) HI 21 cm observations of the supernova remnant(SNR) PKS0607+17 and HII region S261 using Arecibo 305-m telescope. The observation was to investigate whether the high-velocity(HV) gas detected in the southern area of PKS0607+17 by Koo & Heiles(1991) is physically associated with the SNR or not. The velocity of the HV gas ranges from +64 km/s to +87 km/s, which is difficult to result from the Galactic rotation. The HV gas could be the gas accelerated by supernova blast wave. However, because the observation of Koo and Heiles(1991) was carried out using Hat Creek radio telescope(FWHM ≃ ≃ 36'), the association of the HV gas with the SNR could not be investigated. Using the Arecibo HI 21cm data, we have found that the HV gas appears m the southern part of the SNR and its velocity ranges from +61 km/s to +77 km/s. But the HV gas is scattered m the whole field, not only toward PKS0607+17 but also outside the SNR Accordingly the HV gas is probably not associated with the SNR, but is accidentally aligned along the same line of sight toward the SNR. Instead we have found that HI clouds at low velocities could be possibly associated with the SNR. In Arecibo HI 21cm channel maps the HI gas seems to surround the southern boundary of the SNR at VLSR VLSR = +19.6 ~ +40.2 km/s. But because the region of the Arecibo HI 21cm observation is not wide enough to examine the HI gas distribution, we investigated this area using the Berkely low-latitude HI survey data(Weaver & Williams 1974) too. There we found HI gas surrounding the radio continuum boundary of PKS0607+17 at VLSR VLSR = +21.6 ~ +258 km/s. It is possible that this HI gas is associated with the SNR, in which case, the velocity of the SNR Vo Vo ≃ ≃ +26 km/s, its distance d ≃ ≃ 12.5 kpc and its radius R ≃ ≃ 145 pc. If we assume that the expansion velocity is ~10 km/s, then the age of the SNR is ∼4.4×106 ∼4.4×106 years. PKS0607+17 could be one of the oldest SNRs in the Galaxy. We also studied HI propertities of the HII region S261, which is ∼1∘ ∼1∘ away from PKS0607+17. There has been no high-resolution m 21 cm observational study on S261. We discovered HI cloud located at the north-eastern part of S261 at VLSR VLSR = +5 km/s ~ +10 km/s, which is possibly associated with the HII region. The central velocity of the HI cloud VLSR VLSR = +7.2 km/s and the corresponding distance d = 1.5 kpc. This velocity is comparable to the radio recombination line velocities.
        5,800원
        397.
        1997.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        SOFT( So–––lar F––lare T––elescope So_larF_lareT_elescope ) installed at BOAO(Bohyunsan Optical Astronomy Observatory) is purposed for observing solar active regions using four refractors on single mount with a 400"×300" 400"×300" field of view: Two refractors with a diameter of 15cm(f15) are observe the white light and Hα Hα , and the other two refractors with a diameter of 20cm(f8) are observe the magnetic field distribution and Doppler shifts at the solar chromosphere. Three Lyot filters, one of the most important observational instruments, are installed on the optical rails for VMG, LMG, and Hα Hα that possible to very narrow pass band observation under high precision stability of temperature. From the combination of KD*P and quarter wave plate in the Lyot filter possible observe the magnetic fields strength and doppler shifts by using the characteristics of polarization components. In this paper, we introduce the basic characteristics, optical system, and monitor system of the SOFT.
        4,200원
        398.
        1997.12 구독 인증기관·개인회원 무료
        400.
        1997.12 구독 인증기관·개인회원 무료