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1.
本课题的研究目的是利用R(红)—I(近红外)两色照相测光方法,搜寻银道带天区的红外超天体,并证认IRAS点源(文[1])的近红外光学对应体,本文是一组文章的第三篇,在船底天区发现了89个红外超天体,并证认出其中12个是IRAS点源的对应体。  相似文献   

2.
本课题的研究目的是利用R(红)-l(近红外)两色照相测光方法,搜寻银道带天区的红外超天体,并证认IRAS点源的近红外光学对应体。本文是一组文章的第二篇。在天坛天区发现了225个红外超天体,并证认出其中27个为IRAS点源的对应体。  相似文献   

3.
从COMBO-17数字巡天数据里,选择了CDFS(Chandra Deep Field South)天区中1231个测光红移在0.1~0.3之间的暗蓝星系作为样本,研究了这些星系分别在只有光学波段和光学加近红外波段数据情况下做测光红移得到的红移分布,以及这些星系在静止参考系下的能谱分布(Spectral Energy Distributions,SEDs)特征.结果表明有183个星系在利用光学加近红外波段数据做测光红移时得到的红移大于1.2,它们的误差为0.046,提高测光的信噪比也有利于区分这类被光学波段误认为低红移的星系.这些暗蓝星系中高红移星系的观测近红外流量相对于光学流量有上升的趋势,而低红移星系的观测近红外流量相对于光学流量有下降的趋势.  相似文献   

4.
对20颗依巴谷(Hipparcos)卫星所观测的碳星作了近红外JHK测光,由近红外观测结果估算了其在K波段的热改正BCK和视热星等mbpl以及有效温度Te,结合依巴谷卫星所得视差,得到其中一些星的绝对热星等Mbol。  相似文献   

5.
光学近红外相机CASCAM(Chinese Academy of Sciences.Camera)采用光学CCD和近红外阵列HAWMH-1(HgCdTe Astronomical Wide Area Infrared Imaging)探测器,配备兴隆2.16m望远镜可同时进行光学、近红外成像和偏振观测。CASCAM的机械系统主要包括光学箱、真空箱以及致冷设计。其中光学箱是相机光学系统和探测器的载体,同时防止来自光学箱外部的红外热辐射;真空箱位于光学箱外部,它是整个系统的机械支撑,保证相机有良好的真空密封性能,并和真空泵、冷冻机一起构成了相机的致冷系统。  相似文献   

6.
在Li-Paczynski新星(LP新星)模型被提出以及短暴的余辉被确认后,人们就积极地在短暴的光学(或光学-近红外)对应体中寻找LP新星存在的证据。第2章总结2013年之前的观测结果。第3、4章分别介绍短暴GRB 130603B、GRB 060614的基本性质与它们的近红外对应体的解释,它们的近红外超可能是LP新星存在的信号。第5章介绍短暴GRB 080503的基本性质以及它的光学对应体与X射线对应体的解释,它的光学与X射线光变曲线的晚期再增亮被解释为中子星并合之后的磁星加热的喷射物辐射(Merger-Nova辐射)。如果对于以上短暴伴随的光学-近红外对应物的解释正确,那么它们就给出了短暴与一些特殊的长暴来自致密星并合的第一批证据。除产生LP新星(与Merger-Novae)外,致密星并合之前的高速轨道运动与并合自身都将产生强烈的引力波暴(Gravitational-Wave Bursts,GWBs)。随着引力波时代的到来,致密星并合对应的各种电磁波现象的理论研究与观测受到更加密集的关注。由于引力波暴定位的不确定性较大,因此伴随引力波暴的LP新星可以作为引力波暴精确定位的最佳候选者之一。正在快速发展的高频度宽场光学-近红外巡天将对LP新星等现象进行富有成效的探索,并与引力波探测研究互相影响。因此,我们在最后介绍未来探测LP新星的方法及其多信使探测的前景。  相似文献   

7.
主要介绍了抚仙湖1 m新真空太阳望远镜(the 1-meter New Vacuum Solar Telescope,NVST)6 m水平式近红外光谱仪的安装过程和实测结果。主要讨论内容是光路设计特点、光学系统的装调以及利用该光谱仪对活动区NOAA 11662黑子进行的初步近红外光谱实测(波长1.56μm附近)。成功观测到由黑子强磁场造成的Fe I 1.56μm谱线裂变现象,并初步估算了磁场强度。该光谱的成功装调和使用,充分实现了对9 m光谱仪光学系统的整体检测,为9 m光谱仪的安装调试提供了宝贵的经验和参考。  相似文献   

8.
致密星并合(中子星-中子星并合与中子星-黑洞并合)后抛射出的富中子(neutron rich)物质是合成r过程元素(r-process elements)的重要场所之一,近17年来的理论研究认为,这些r过程元素衰变产生的能量在热化后将形成光学-近红外(Optical-NIR)辐射,这种光学-近红外暂现现象被称为"Li-Paczynski新星(Li-Paczynski novae)",简称为"LP新星",由于它们的典型峰值亮度约为典型的新星(novae)亮度的1000倍,因此又被称为"千新星(Kilonovae)"。此外,理论与观测都直接或间接地表明致密星并合在一定条件下会形成持续时间较短(T_(90)(?)2 s)的伽玛射线暴(简称短暴,SGRBs),且大部分短暴可能源自致密星并合。在短暴的余辉被确定后,人们就致力于搜寻伴随短暴的LP新星。介绍近17年来LP新星的理论进展。  相似文献   

9.
本文给出在美国佛罗里达(Florida) 大学的Rosemary Hill天文台研制的一个观测资料实时处理的近红外光度计的主要结构和性能。着重讨论了该仪器的数据采集系统,并对将来仪器的改进提出了一些设想。  相似文献   

10.
本篇报告详细介绍了装有圆形可变滤光片的最新的InSb(锑化铟)红外探测器的各项性能和特点,以及使用前的检验测量的实验情况;并报告了最终检测的结果。一些装备的更新,使整个近红外光度测量系统的性能水平大大提高。  相似文献   

11.
In a search for infrared excess objects near the galactic plane, a star field of 28.5 square degrees in Vela has been measured on UK Schmidt plates R4272 and 14183 with the Cosmos machine at Royal Observatory, Edinburgh. The magnitude limit is around 20 in R and around 19 in I. 131 infrared excess objects with colour index R-I > 2.5 are discovered in the field, and 3 red stellar objects have been identified as the optical counterparts of IRAS point sources.  相似文献   

12.
We present a new survey for Hα emission objects in the Circinus cloud complex and introduce an efficient photometric method for detecting Hα emission via observations in a narrow‐band filter. The observed flux is compared to a blackbody fit of the continuum. Our search strategy reveals 20 stars with strong Hα emission (EW > 10 Å), eight of them being new detections. All Hα stars display infrared excess corroborating their youth. On the other hand, the region contains a number of infrared excess objects that do not show Hα emission. Our results support the picture that accretion – as witnessed by Hα emission – is a highly variable phenomenon. Therefore, Hα surveys can only trace the temporarily active objects. In contrast, infrared excess is a more robust tracer that reveals most of the population of young stellar objects in a star forming region. Our analysis of the general stellar content of the region yields a reliable distance of 450 pc for the Circinus cloud. Moreover, we find a ratio of total‐to‐selective extinction of RV = 2.8 suggesting that smaller‐than‐normal dust grains may be present. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

13.
The recent spectral evolution of the three peculiar emission-line objects with IR excess V1016 Cyg, HM Sge, and MWC 349 is described, on the basis of data obtained at the Asiago (blue and red spectral regions) and Haute Provence (near infrared) Observatories. In the near infrared spectral region, details are given concerning the data briefly described in IAU Circular No. 3498 (Andrillat and Swings, 1980).Based on observations performed at the Haute Provence (CNRS, France) and Asiago (Italy) Observatories.  相似文献   

14.
We have compiled infrared photometric data from the literature of practically all T Tauri stars found up to date including 444 classical T Tauri stars (CTTSs), 1698 weak-line T Tauri stars (WTTSs) and 1258 not classified T Tauri stars (3400 in total) in addition to 196 post-T Tauri stars (PTTSs). From this data bank we extract the infrared characteristics of the different groups and discuss different origins of the infrared radiation. The observational data are taken from the AKARI, IRAS, WISE and 2MASS missions. We show that in the wavelength range 1–140 μm, all T Tauri stars have infrared excesses. CTTSs have more infrared excess than WTTSs, while PTTSs have little or no infrared excess. We found that in the 1–3 μm wavelength range the infrared emission of T Tauri stars is mainly due to thermal radiation from the photosphere and hot dust grains from circumstellar envelopes. In the 3–140 μm wavelength range the infrared emission of T Tauri stars is mainly due to radiation from dusty/gaseous disks surrounding the stars. In addition, we also make a comparison between T Tauri stars and Herbig AeBe stars (HAeBe). There are some differences between these two kinds of objects in that for HAeBe stars the infrared radiation as a rule originates in dusty/gaseous disks in the 1–3 μm wavelength range, while in the range 3–12 μm it is possibly due to PAH emission for about half of HAeBe stars. In other wavelength ranges both kinds of stars have similar infrared characteristics indicating emission from dusty/gaseous disks.  相似文献   

15.
Using different sky surveys, we studied IRAS sources and embedded clusters located in the G345.5+1.5 region. Our analysis comprises multi-wavelength (optical to radio) data, exploited using various methods: photometry, near-infrared spectroscopy for ten stars in the embedded cluster DBS-114, and astrometry. We estimated the main parameters of the embedded stellar populations in the G345.5+1.5 molecular cloud, such as their extent, reddening, age, and mass. We also found a consistent distance value using different approaches. For each studied population, we classified several point objects as early main sequence stars, stars with infrared excess, and class I/II YSOs. For the particular case of DBS 114, our spectral classification revealed four B-type stars, and we used astrometric information from GAIA EDR3. The combination of optical and infrared information revealed an abnormal reddening law in some embedded clusters. Our analysis favored a scenario with a Lyman continuum emission excess at some of the studied stellar populations.  相似文献   

16.
In this paper, the variations of BL Lac objects in the infrared band are given. The relation between infrared magnitude-K and redshift is discussed for BL Lac objects, FRI, and FRII(G) radio galaxies. The results show that the faintest optical and infrared magnitudes are correlated, the BL Lac objects with large infrared variation have large optical variation, and the unified scheme of BL Lac objects should include FRI and FRII(G) radio galaxies, which support the results of Xie et al. (1993) and Owen, Ledlow and Keel (1996). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
Spectroscopic observations by the 2.6 m BAO telescope of IRAS galaxies identified on the basis of the First Byurakan Survey (BIG objects) are reported. Slit spectra were obtained for 16 objects, including components of 7 multiple systems and 2 individual galaxies. The red shifts were measured, and the radial velocities, distances, absolute stellar magnitudes, and infrared and far infrared luminosities were calculated. A diagnostic diagram has been constructed based on the intensity ratios of emission lines and the activity types of the objects have been determined. Two LINERs, five galaxies with composite spectra (Comp, one of which has Sy2 features) and seven HII regions were found. Two objects are ultraluminous IR galaxies (ULIG). It is shown that all the multiple systems are physical pairs or groups. The observed high IR luminosity confirms the view that ULIG/HLIGs may be associated with interactions of galaxies.  相似文献   

18.
A UK Schmidt prism plate centered on SA94 has been used to search for an emission line and ultraviolet excess objects and to inspect all the colour class 1 and 2 blue objects and the possible variables selected previously. 322 QSO candidates have been found.  相似文献   

19.
We present the Spitzer Space Telescope Infrared Array Camera observations for a sample of local elliptical galaxies to study later stages of active galactic nucleus (AGN) activity. A sample of 36 elliptical galaxies is selected from the Palomar spectroscopic survey. We detect nuclear non-stellar infrared emission in nine of them. There is unambiguous evidence of circumnuclear dust in these nine galaxies in their optical images. We also find a remarkable correlation between the infrared excess emission and the nuclear radio/X-ray emission, suggesting that infrared excess emission is tightly related to nuclear activity. The possible origin of infrared excess emission from hot dust heated by the central AGN is supported by the spectral indices of the infrared excess emission.  相似文献   

20.
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