Related papers: Spectroscopy of two PN candidates in IC10
Mid-IR observations of planetary nebulae (PNe) have revealed diffuse emission associated to their main nebular shells and outer envelopes or haloes. The interpretation of this emission is uncertain because the broad-band mid-IR images may…
We report initial results from an ongoing spectroscopic survey of central stars of faint planetary nebulae (PNe), obtained with the Low-Resolution Spectrograph on the Hobby-Eberly Telescope. The six PN nuclei (PNNi) discussed here all have…
By applying quantum chemical calculation, interstellar infrared spectrum was categorized to three classes. Type-A show unusual feature of strong peaks at 11.3,12.9, and 14.0 micrometer. Usually observed 6.2, 7.7, and 8.6 micrometer bands…
In the framework of the Local Group Census (LGC), a survey of the Local Group (LG) galaxies above Dec=$-30^\circ$, which is aimed at surveying their populations with strong emission lines, we have searched for planetary nebulae (PNe) in the…
About 3,500 planetary nebulae (PNe) are currently known in the Milky Way, which shows a great discrepancy with the expected number for these objects, regardless of the reference used, $33-59 \times 10^{3}$. The same holds for symbiotic…
We use imaging and spectroscopy from the Hubble Space Telescope (HST) to examine the properties of a bright planetary nebula (PN) projected within M31's young open cluster B477-D075. We show that the probability of a chance superposition of…
The Hubble diagrams in B, V, and I of a complete sample of 35 SNeIa with (B-V) < 0.06 and 1200 < v < 30000 kms^{-1} have a scatter of only 0.1 mag, after small corrections are applied for differences in decline rate Delta m_{15} and color…
(Abridged) Planetary nebulae (PNe) around Wolf-Rayet [WR] central stars ([WR]PNe) constitute a particular photoionized nebula class that represents about 10% of the PNe with classified central stars. We analyse deep high-resolution…
We matched the astrometry of central stars (CSs) of spectroscopically-confirmed Galactic planetary nebulae (PNe) with DR2 Gaia parallaxes ($p$), finding 430 targets in common with $p>0$ and $|\sigma_{\rm p}/p|<1$. A catalog of PNe whose CSs…
We have observed emission line objects located in a 0.26 deg^2 field in the M96 (Leo) group, coincident with the intergalactic HI cloud. The emission line objects were selected using the same procedure as used for the search for…
The H$\alpha$ surface brightness $-$ radius ($S-r$) relation is a robust distance indicator for planetary nebulae (PNe), further enhanced by different populations of PNe having distinct loci in $S-r$ space. Other types of photoionized…
We have identified 38 candidates of intracluster planetary nebulae (ICPNe) in a $34'\times27'$ field in the core of the Virgo cluster based on the Suprime-Cam imaging through two narrow-band filters centered at the redshifted wavelengths of…
The Local Group contains a great number of dwarf irregulars and spheroidals, for which the spectroscopy of individual stars can be obtained. Thus, the chemical evolution of these galaxies can be traced, with the only need of finding…
Planetary nebulae are one of the final stages in the evolution of low and intermediate mass stars. They occur in a variety of shapes. Older and fainter ones are generally more difficult to identify because of the lower surface brightness.…
We study the observables of 158 relatively normal Type Ia supernovae (SNe Ia) by dividing them into two groups in terms of the expansion velocity inferred from the absorption minimum of the Si II 6355 line in their spectra near B-band…
We have obtained V and I-band photometry for about 700 stars in the field of the dwarf irregular galaxy IC 5152, previously considered a possible member of the Local Group. Deep VI color-magnitude diagrams are presented of the main body of…
We identify [Se III] 1.0994 micron in the planetary nebula (PN) NGC 5315 and [Kr VI] 1.2330 micron in three PNe, from spectra obtained with the FIRE spectrometer on the 6.5-m Baade Telescope. Se and Kr are the two most widely-detected…
We report observations of two nearby Type Ia supernovae (SNe Ia) for which observations of Cepheid variables in the host galaxies have been obtained with the Hubble Space Telescope: SN 1994ae in NGC 3370 and SN 1998aq in NGC 3982. For NCG…
As part of an on-going radio supernova monitoring program, we have discovered a variable, compact steep spectrum radio source ~65 arcsec (~4 kpc) from the centre of the starburst galaxy NGC 3310. If the source is at the distance of NGC…
From observations of 7 Type Ia supernovae obtained during the last four years at the Las Campanas and Cerro Tololo Inter-American Observatories, along with previous published data for 9 supernovae, we present JHK Hubble diagrams and derive…