scholarly journals A deep narrowband survey for planetary nebulae at the outskirts of M 33

2018 ◽  
Vol 612 ◽  
pp. A35 ◽  
Author(s):  
R. Galera-Rosillo ◽  
R. L. M. Corradi ◽  
A. Mampaso
Keyword(s):  
Local Group ◽  
Planetary Nebulae ◽  
Wide Field ◽  
Low Surface Brightness ◽  
The Galaxy ◽  
Northern Side ◽  
The Rich ◽  
Red Giant ◽  
Field Imaging ◽  
Projected Distance

Context. Planetary nebulae (PNe) are excellent tracers of stellar populations with low surface brightness, and therefore provide a powerful method to detect and explore the rich system of substructures discovered around the main spiral galaxies of the local group. Aim. We searched the outskirts of the local group spiral galaxy M 33 (the Triangulum) for PNe to gain new insights into the extended stellar substructure on the northern side of the disc and to study the existence of a faint classical halo. Methods. The search is based on wide field imaging covering a 4.5 square degree area out to a maximum projected distance of about 40 kpc from the centre of the galaxy. The PN candidates are detected by the combination of images obtained in narrowband filters selecting the [OIII]λ5007 Å and Hα + [NII] nebular lines and in the continuum g′ and r′ broadband filters. Results. Inside the bright optical disc of M 33, eight new PN candidates were identified, three of which were spectroscopically confirmed. No PN candidates were found outside the limits of the disc. Fourteen additional sources showing [OIII] excess were also discovered. Conclusions. The absence of bright PN candidates in the area outside the galaxy disc covered by this survey sets an upper limit to the luminosity of the underlying population of ~1.6 × 107 L⊙, suggesting the lack of a massive classical halo, which is in agreement with the results obtained using the red giant branch population.

scholarly journals Kinematics of Planetary Nebulae in M51's Tidal Tail

2003 ◽  
Vol 209 ◽  
pp. 633-634
Author(s):  
John J. Feldmeier ◽  
J. Christopher Mihos ◽  
Patrick R. Durrell ◽  
Robin Ciardullo ◽  
George H. Jacoby
Keyword(s):  
Surface Brightness ◽  
Numerical Models ◽  
Planetary Nebulae ◽  
Tidal Tail ◽  
Low Surface Brightness ◽  
Galaxy Interaction ◽  
Self Consistent ◽  
The Galaxy ◽  
Interacting Systems ◽  
Kinematic Properties

The galaxy pair NGC 5194/95 (M51) is one of the closest and best known interacting systems. Despite its notoriety, however, many of its features are not well studied. Extending westward from NGC 5195 is a low surface brightness tidal tail, which can only be seen in deep broadband exposures. Our previous [O III] λ5007 planetary nebulae (PN) survey of M51 recovered this tidal tail, and presented us with a opportunity to study the kinematics of a galaxy interaction in progress. We report the results of a spectroscopy survey of the PN, aimed at determining their kinematic properties. We then use these data to constrain new self-consistent numerical models of the system.

scholarly journals The LAMOST spectroscopic survey of planetary nebulae in M31 and M33

2016 ◽  
Vol 12 (S323) ◽  
pp. 388-389
Author(s):  
Maosheng Xiang ◽  
Xiaowei Liu ◽  
Meng Zhang ◽  
Haibo Yuan ◽  
Zhiying Huo
Keyword(s):  
Radial Velocity ◽  
Planetary Nebulae ◽  
Radial Velocities ◽  
Velocity Measurements ◽  
The Galaxy ◽  
Galaxy Center ◽  
Projected Distance

AbstractWe present LAMOST observations and radial velocity measurements of about 1500 planetary nebulae (PNe) in M31 and M33. Most of the PNe are previously known, but 36 of them are newly discovered in the outskirts of M31, and the furthest one has a projected distance larger than 50 kpc away from the galaxy center. Eighteen objects in the area of M33 are probably newly discovered PNe, and quite a few of them are associated with previously known clusters. For all the 1500 PNe, homogeneous radial velocities are measured from the LAMOST spectra, with a typical uncertainty of a few km s−1.

scholarly journals Probing Galactic Outskirts with Dragonfly

2016 ◽  
Vol 11 (S321) ◽  
pp. 137-146 ◽  
Author(s):  
Roberto Abraham ◽  
Allison Merritt ◽  
Jielai Zhang ◽  
Pieter van Dokkum ◽  
Charlie Conroy ◽  
...  
Keyword(s):  
Surface Brightness ◽  
Wide Field ◽  
Rich Variety ◽  
Neutral Gas ◽  
Early Results ◽  
Low Surface Brightness ◽  
Stellar Halo ◽  
Nearby Galaxies ◽  
The Mean ◽  
The Rich

AbstractWe describe the challenges inherent to low surface brightness imaging and present some early results from the Dragonfly Nearby Galaxies survey. Wide field, ultra-low surface brightness imaging (μg > 31 mag arcsec−2) of the first eight galaxies in the survey reveals a rich variety in the distribution of stars in the outskirts of luminous nearby galaxies. The mean stellar halo mass fraction is 0.009 ± 0.005 with a peak-to-peak scatter of a factor of > 100. Some galaxies in the sample feature strongly structured halos resembling that of M31, but three of the eight galaxies have halos that are completely undetected in our data. We conclude that spiral galaxies as a class exhibit a rich variety in stellar halo properties, implying that their assembly histories have been highly non-uniform. While the outskirts of some galaxies are dominated by halos with the rich substructures predicted by numerical simulations, in other cases the outermost parts of galaxies are simply the extrapolated smooth starlight from enormous stellar disks that closely trace neutral gas morphology out to around 20 scale lengths.

scholarly journals Wide-Field Imaging of Halley’s Comet During 1985-1986 Using Schmidt-Type Telescopes

1984 ◽  
Vol 78 ◽  
pp. 233-235
Author(s):  
J.C. Brandt ◽  
D.A. Klinglesmith ◽  
M.B. Niedner ◽  
J. Rahe
Keyword(s):  
Time Resolution ◽  
Surface Brightness ◽  
Large Scale ◽  
Wide Field ◽  
Low Surface Brightness ◽  
The World ◽  
Halley's Comet ◽  
Worldwide Network ◽  
Field Imaging ◽  
Wide Field Imaging

AbstractPhotographic imaging of the plasma- and dust-tails of bright comets requires fast (f<4.0), wide-field (F0V>5°) optics for the proper recording of these large, low surface brightness features. Schmidts and astrographs are well-suited to this task and a large number of these instruments around the world will be turned toward Halley's Comet in 1985-1986 in support of the Large-Scale Phenomena Discipline of the International Halley Watch (IHW). This “worldwide network” should provide imagery with a time resolution never before realized in the study of a comet, and major breakthroughs in the understanding of highly-variable, elusive plasma processes in comets are expected. The imagery will also provide support for the GIOTTO, VEGA, AND PLANET-A deep space probes to the comet.

scholarly journals Dust and molecules in extra-galactic planetary nebulae

2015 ◽  
Vol 11 (A29B) ◽  
Author(s):  
D. A. García-Hernández
Keyword(s):  
Solid State ◽  
Gas Phase ◽  
Organic Molecules ◽  
Local Group ◽  
Planetary Nebulae ◽  
Circumstellar Envelopes ◽  
The Galaxy ◽  
Models Comparison ◽  
Polycyclic Aromatic ◽  
Complex Organic

AbstractExtra-galactic planetary nebulae (PNe) permit the study of dust and molecules in metallicity environments other than the Galaxy. Their known distances lower the number of free parameters in the observations vs. models comparison, providing strong constraints on the gas-phase and solid-state astrochemistry models. Observations of PNe in the Galaxy and other Local Group galaxies such as the Magellanic Clouds (MC) provide evidence that metallicity affects the production of dust as well as the formation of complex organic molecules and inorganic solid-state compounds in their circumstellar envelopes. In particular, the lower metallicity MC environments seem to be less favorable to dust production and the frequency of carbonaceous dust features and complex fullerene molecules is generally higher with decreasing metallicity. Here, I present an observational review of the dust and molecular content in extra-galactic PNe as compared to their higher metallicity Galactic counterparts. A special attention is given to the level of dust processing and the formation of complex organic molecules (e.g., polycyclic aromatic hydrocarbons, fullerenes, and graphene precursors) depending on metallicity.

scholarly journals Nearby Blue Compact Dwarf Galaxy NGC 6789

1999 ◽  
Vol 192 ◽  
pp. 253-258
Author(s):  
I. Drozdovsky ◽  
N. Tikhonov
Keyword(s):  
Surface Brightness ◽  
Dwarf Galaxy ◽  
High Surface ◽  
Low Surface Brightness ◽  
The Galaxy ◽  
Metal Abundance ◽  
The Mean ◽  
Red Giant ◽  
Halo Population ◽  
Blue Compact Dwarf Galaxy

We present the results of a detailed BVRI and Hα study of the isolated nearby blue compact dwarf (BCD) galaxy NGC 6789. Judging from the literature the observed galaxy has not yet been resolved into stars up to now. On CCD frames obtained with 6m BTA telescope and 2.5m Nordic telescope the galaxy is well resolved. Its colour-magnitude diagram confirms the two component (core-halo) galaxy morphology, which consists of two stellar populations distinct in structure and colour: an inner high surface-brightness young population within 150 pc from the center of the galaxy, and a relatively low surface-brightness intermediate-age population extending out to at least 600 pc. The distance to the galaxy, estimated from the tip of the red giant branch (TRGB) is 2.1 Mpc which places NGC 6789 close to the Local Group. From the mean colour of the RGB, the mean metal abundance of the halo population is estimated as [Fe/H] ≃ −1 dex.

scholarly journals Abundances in Local Group Planetary Nebulae

1995 ◽  
Vol 10 ◽  
pp. 480-482
Author(s):  
James B. Kaler
Keyword(s):  
Local Group ◽  
Initial Conditions ◽  
Planetary Nebulae ◽  
Magellanic Clouds ◽  
Chemical Compositions ◽  
Core Mass ◽  
Know How ◽  
Chemical Enrichment ◽  
Clear Link ◽  
The Galaxy

We are able to measure the chemical compositions of hundreds of planetary nebulae in our own Galaxy and in the Magellanic Clouds. Why, therefore, do we need to expend the effort to observe much more difficult targets in other Local Group galaxies? A severe lack of distances does not allow us to place Galactic planetary nuclei on the log L-log T plane with any degree of accuracy, so we cannot properly examine composition differences relative to core mass and state of evolution. We can perform such tasks for Magellanic Cloud objects, but do not know how the Clouds’ low-metallicities affect the results, and thus do not know how this sample of planetaries relates to the nebulae in our own system. We know, for example, that in the Clouds, nitrogen enrichment begins above a core mass of about 0.68 M⊙ (Kaler and Jacoby 1990), but other than a clear link between core mass and chemical enrichment in the Galaxy, do not know at what point it becomes important. To study such relationships, we therefore have to go to other galaxies with a variety of initial conditions for which distances are secure, namely those of the Local Group.

scholarly journals Searching for planetary nebulae at the Galactic halo via J-PAS

2015 ◽  
Vol 11 (S317) ◽  
pp. 304-305
Author(s):  
Denise R. Gonçalves ◽  
T. Aparício-Villegas ◽  
S. Akras ◽  
A. Cortesi ◽  
M. Borges-Fernandes ◽  
...  
Keyword(s):  
Galactic Halo ◽  
Narrow Band ◽  
Narrow Band Imaging ◽  
Broad Band ◽  
Planetary Nebulae ◽  
Accelerating Universe ◽  
Wide Field ◽  
The Galaxy ◽  
First Results ◽  
Chemical Conditions

AbstractThe Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS) is a narrow-band imaging, very wide field cosmological survey. It will last 5 years and will observe 8500 sq. deg. of the sky. There will be 54 contiguous narrow-band filters of 145Å FWHM, from 3,500 to 10,000Å. Two broad-band filters will be added at the extremes, UV and IR, plus the 3–g, r, and i– SDSS filters. Thus, J-PAS can be an important tool to search for new planetary nebulae (PNe) at the halo, increasing their numbers, because only 14 of them have been convincingly identified in the literature. Halo PNe are able to reveal precious information for the study of stellar evolution and the early chemical conditions of the Galaxy. The characteristic low continuum and intense emission lines of PNe make them good objects to be searched by J-PAS. Though covering a significantly smaller sky area, data from the ALHAMBRA survey were used to test our J-PAS strategy to search for PNe. Our first results are shown in this contribution.

scholarly journals Hyper Wide Field Imaging of the Local Group Dwarf Irregular Galaxy IC 1613: An Extended Component of Metal-poor Stars

2019 ◽  
Vol 880 (2) ◽  
pp. 104 ◽  
Author(s):  
Ragadeepika Pucha ◽  
Jeffrey L. Carlin ◽  
Beth Willman ◽  
Jay Strader ◽  
David J. Sand ◽  
...  
Keyword(s):  
Local Group ◽  
Wide Field ◽  
Irregular Galaxy ◽  
Extended Component ◽  
Field Imaging ◽  
Wide Field Imaging

scholarly journals The Outer Halo Cluster System of NGC 1399

2002 ◽  
Vol 207 ◽  
pp. 324-326 ◽  
Author(s):  
B. Dirsch ◽  
D. Geisler ◽  
T. Richtler ◽  
J.C. Forte
Keyword(s):  
Globular Cluster ◽  
Cluster System ◽  
Wide Field ◽  
Ccd Photometry ◽  
The Galaxy ◽  
Specific Frequency ◽  
Field Imaging ◽  
Wide Field Imaging

We investigate the outer halo globular cluster population of NGC 1399. This study uses wide-field imaging of this cluster system, which covers the largest area studied with CCD photometry until now. The cluster system of NGC 1399 is found to extend further than 100 kpc from the galaxy. A population of metal-rich, as well as metal-poor clusters has been identified at these large radii. At radii smaller than 55 kpc the specific frequency of the red cluster system remains constant, while that of the blue clusters increases proportional tor0.8±0.2. For larger radii, the uncertainty of the galaxy light profile does not permit any reliable statement.

Sign in / Sign up

Export Citation Format

Share Document