Search Publications
An Improved Pair Method to Probe the Dust Extinction Law
Gao, Jian; Ren, Yi; Wang, Yuxi +1 more
Dust extinction law is crucial to recover the intrinsic energy distribution of celestial objects and infer the characteristics of interstellar dust. Based on the traditional pair method, an improved pair method is proposed to model the dust extinguished spectral energy distribution (SED) of an individual star. Instead of the mathematically paramet…
Spectral study of V565 Mon: probable FU Ori-like or chemically peculiar star
Andreasyan, Hasmik
We present a detailed spectroscopic study of pre-main sequence star V565 Mon, which is the illuminating star of the Parsamian 17 cometary nebula. Observations were performed with the 2.6 m telescope in Byurakan Astrophysical Observatory on 2018 February 15. Radial velocities and equivalent widths of the most prominent lines of V565 Mon are present…
Discovery of extended structures around two evolved planetary nebulae M2-55 and Abell 2
Zhang, Yong; Hsia, Chih-Hao; Zhang, Xi-Liang +1 more
We report a multi-wavelength study of two evolved planetary nebulae (PNs)M2-55 and Abell 2. Deep optical narrow-band images ([O III], Hα, and [N II]) of M2-55 reveal two pairs of bipolar lobes and a new faint arc-like structure. This arc-shaped filament around M2-55 appears as a well-defined boundary from southwest to southeast, strongly suggestin…
Galactic coordinate system based on multi-wavelength catalogs
Zhu, Zi; Liu, Jia-Cheng; Ding, Ping-Jie
The currently used Galactic coordinate system (GalCS) is based on the FK5 system at J2000.0, which was transformed from the FK4 system at B1950.0. The limitations and misunderstandings related to this transformed GalCS can be avoided by defining a new GalCS that is directly connected to the International Celestial Reference System (ICRS). With mor…
Sequential clustering of star formations in IC 1396
Li, Jin-Zeng; Huang, Ya-Fang
We present a comprehensive study of the H II region IC 1396 and its star forming activity, in which multi-wavelength data ranging from the optical to the near- and far-infrared were employed. The surface density distribution of all the 2MASS sources with a certain detection toward IC 1396 indicates the existence of a compact cluster spatially cons…
Studies of a possible new Herbig Ae/Be star in the open cluster NGC 7380
Mathew, Blesson; Banerjee, D. P. K.; Subramaniam, Annapurni +3 more
We present a study of the star 2MASS J22472238+5801214 with the aim of identifying its true nature which has hitherto been uncertain. This object, which is a member of the young cluster NGC 7380, has been variously proposed to be a Be star, a D-type symbiotic and a Herbig Ae/Be star in separate studies. Here we present optical spectroscopy, near-I…
Cross-correlations between 21 cm, X-ray and infrared backgrounds
Shan, Huan-Yuan; Qin, Bo
The history of the cosmological reionization is still unclear. Two ionizing sources, stars and QSOs, are believed to play important roles during this epoch. Besides the 21 cm signals, the infrared emission from Pop III stars and X-ray photons from QSOs can be powerful probes of the reionization. Here we present a cross-correlation study of the 21c…