A Survey of Novae in M83

Abstract The results of the first synoptic survey of novae in the barred spiral and starburst galaxy, M83 (NGC 5236), are presented. A total of 19 novae and one background supernova were discovered during the course of a nearly 7 year survey comprised of over 200 individual nights of observation between 2012 December 12 and 2019 March 14. After correcting for the limiting magnitude and the spatial and temporal coverage of the survey, the nova rate in M83 was found to be R = 19+5 −3 yr−1. This rate, when normalized to the K-band luminosity of the galaxy, yields a luminosity-specific nova rate, ν K = 3.0+0.9 −0.6 × 10−10 yr −1 L ⊙,K −1. The spatial distribution of the novae is found to be more extended than the overall galaxy light suggesting that the observed novae are likely dominated by a disk population. This result is consistent with the observed novae light curves, which reveals that the M83 novae are on average more luminous at maximum light and fade faster when compared with novae observed in M31. Generally, the more luminous M83 novae were observed to fade more rapidly, with the complete sample being broadly consistent with a linear maximum magnitude versus rate of decline relation.

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Long-term Photometric Monitoring of Cool Hydrogen-deficient Carbon Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100037854 ◽

1995 ◽

Vol 155 ◽

pp. 431-432

Author(s):

P.L. Cottrell ◽

A.C. Gilmore ◽

P.M. Kilmartin ◽

W.A. Lawson

Keyword(s):

Large Amplitude ◽

Stellar Atmospheres ◽

Light Curves ◽

Maximum Light ◽

Stellar Nucleosynthesis ◽

Grain Formation ◽

The Galaxy ◽

Photometric Monitoring ◽

Low Amplitude

Interest in the hydrogen-deficient carbon (HdC) stars, and the R Coronae Borealis (RCB) stars in particular, has been rekindled by the realisation that these stars provide the potential for testing models in a number of areas. These include: pulsation theory; grain formation; grain evolution; stellar nucleosynthesis and extended stellar atmospheres.Observational work on these objects has increased dramatically over the last 10 years. This has included both spectroscopic and photometric projects, see Lambert & Rao (1994) and Lawson et al. (1990).We have continued to observe a number of the cool HdC stars in the Galaxy and the LMC and now have light curves exceeding 2000 days in duration for many of these objects. In particular, we are observing the RCB stars to investigate both the low amplitude, pulsation-related variations present at maximum light and the photometric behaviour during the large amplitude declines.

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Sub-System of Novae

Symposium - International Astronomical Union ◽

10.1017/s0074180900018623 ◽

1957 ◽

Vol 3 ◽

pp. 71-76 ◽

Cited By ~ 1

Author(s):

I. M. Kopylov

Keyword(s):

Spatial Distribution ◽

Planetary Nebulae ◽

Light Curves ◽

The Other ◽

Physical Processes ◽

Similar Nature ◽

The Galaxy ◽

Absolute Magnitudes ◽

Mutual Relations ◽

Light Maximum

In order to discover the cause of the outbursts of novae, a study of the physical processes taking place in novae during such explosions is not sufficient. A number of other, and no less important, properties and peculiarities of novae must also be investigated. Such properties are, for instance: the absolute magnitudes at light maximum and minimum, the temperatures, the light curves and their variations, the position of the novae on the Hertzsprung-Russell diagram, their spatial distribution in the Galaxy, and the mutual relations between the novae and other objects of similar nature (such as the recurrent novae, super-novae, nova-like stars, and the nuclei of planetary nebulae). A hypothesis of the origin of the outbursts of novae should be founded upon all these data as well as the other properties of novae.

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AHubble Space TelescopeSurvey for Novae in M87. II. Snuffing out the Maximum Magnitude–Rate of Decline Relation for Novae as a Non-standard Candle, and a Prediction of the Existence of Ultrafast Novae

The Astrophysical Journal ◽

10.3847/1538-4357/aa65cd ◽

2017 ◽

Vol 839 (2) ◽

pp. 109 ◽

Cited By ~ 19

Author(s):

Michael M. Shara ◽

Trisha Doyle ◽

Tod R. Lauer ◽

David Zurek ◽

Edward A. Baltz ◽

...

Keyword(s):

Maximum Magnitude ◽

Standard Candle ◽

Rate Of Decline

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Where Does the Galaxy End?

Symposium - International Astronomical Union ◽

10.1017/s0074180900230568 ◽

1996 ◽

Vol 169 ◽

pp. 669-680

Author(s):

F.D.A. Hartwick

Keyword(s):

Spatial Distribution ◽

Globular Clusters ◽

Semimajor Axis ◽

Three Dimensional ◽

Minor Axis ◽

Spatial Extension ◽

The Galaxy ◽

Nested Hierarchy ◽

Satellite Galaxies ◽

Dimensional Surface

The spatial distribution of the outlying satellites of the Galaxy has been determined by fitting a three dimensional surface to the positions of 10 companion galaxies and 13 distant globular clusters. Both groups show a highly flattened distribution whose minor axes are aligned to within ∼ 5°. The combined group of 23 objects shows a triaxial distribution with semimajor axis extending ∼ 400 kpc. The minor axis is inclined at ∼ 76° to the Galactic poles. There is a suggestion of a nested hierarchy consisting of satellite galaxies, globular clusters, and distant halo field stars, in order of decreasing spatial extension.

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LIGHT SUPERCONDUCTING STRINGS IN THE GALAXY

International Journal of Modern Physics D ◽

10.1142/s0218271807011802 ◽

2007 ◽

Vol 16 (12b) ◽

pp. 2399-2405 ◽

Cited By ~ 4

Author(s):

FRANCESC FERRER ◽

TANMAY VACHASPATI

Keyword(s):

Magnetic Field ◽

Spatial Distribution ◽

Particle Physics ◽

Milky Way ◽

Gamma Ray ◽

Galactic Center ◽

Line Emission ◽

Galactic Magnetic Field ◽

The Galaxy ◽

Intense Source

Observations of the Milky Way by the SPI/INTEGRAL satellite have confirmed the presence of a strong 511 keV gamma ray line emission from the bulge, which requires an intense source of positrons in the galactic center. These observations are hard to account for by conventional astrophysical scenarios, whereas other proposals, such as light DM, face stringent constraints from the diffuse gamma ray background. Here we suggest that light superconducting strings could be the source of the observed 511 keV emission. The associated particle physics, at the ~ 1 TeV scale, is within the reach of planned accelerator experiments, while the distinguishing spatial distribution, proportional to the galactic magnetic field, could be mapped by SPI or by future, more sensitive satellite missions.

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Bulge δ Scuti stars in the MACHO database

Symposium - International Astronomical Union ◽

10.1017/s0074180900116808 ◽

1997 ◽

Vol 189 ◽

pp. 293-298

Author(s):

D. Minniti ◽

C. Alcock ◽

D.R. Alves ◽

T.S. Axelrod ◽

A.C. Becker ◽

...

Keyword(s):

Spatial Distribution ◽

High Amplitude ◽

Light Curves ◽

Evolutionary Status ◽

Absolute Magnitudes ◽

Scuti Stars ◽

Δ Scuti Stars

We describe the search for δ Scuti stars in the MACHO database of bulge fields. Concentrating on a sample of high amplitude δ Scutis, we examine the light curves and pulsation modes. We also discuss their spatial distribution and evolutionary status using mean colors and absolute magnitudes.

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Cepheids in the Nearby Galaxy IC 1613

International Astronomical Union Colloquium ◽

10.1017/s0252921100057456 ◽

2000 ◽

Vol 176 ◽

pp. 157-160

Author(s):

E. Antonello ◽

L. Mantegazza ◽

D. Fugazza ◽

M. Bossi ◽

S. Covino

Keyword(s):

Magellanic Clouds ◽

Light Curves ◽

Nearby Galaxy ◽

Short Discussion ◽

The Galaxy ◽

First Results ◽

First Time

AbstractA summary of the first results of a search for Cepheids in IC 1613 is reported along with a short discussion of the adopted technique, a comparison of the characteristics of Cepheid light curves in the Galaxy, Magellanic Clouds and IC 1613, and a possible application for a P–L relation derivation. First overtone Cepheids have been identified for the first time in a galaxy farther than the Magellanic Clouds.

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Star clusters as tracers of galactic subsystems

Symposium - International Astronomical Union ◽

10.1017/s0074180900123435 ◽

1993 ◽

Vol 153 ◽

pp. 323-324

Author(s):

B. Barbuy ◽

E. Bica ◽

S. Ortolani

Keyword(s):

Spatial Distribution ◽

Galaxy Formation ◽

Formation Process ◽

Globular Clusters ◽

Star Clusters ◽

Open Clusters ◽

Horizontal Branch ◽

The Galaxy ◽

Magnitude Difference

We have obtained CCD BVRI colour-magnitude diagrams for a series of disk globular clusters, improving parameters and detecting a new one: Lyngå 7. Using the magnitude difference between turn-off and horizontal branch Δ(TO-HB) as an age discriminator, and their spatial distribution we compare old disk open clusters, young halo globular clusters, and metal-rich disk globular clusters, obtaining clues to the Galaxy formation process.

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Spatial distribution of exoplanet candidates based on Kepler and Gaia data

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936692 ◽

2020 ◽

Vol 635 ◽

pp. A191

Author(s):

A. Maliuk ◽

J. Budaj

Keyword(s):

Spatial Distribution ◽

Galactic Plane ◽

Open Clusters ◽

Field Of View ◽

Solar Neighbourhood ◽

Spatial Gradients ◽

The Galaxy ◽

Formation And Evolution ◽

F Stars ◽

Galactic Longitude

Context. Surveying the spatial distribution of exoplanets in the Galaxy is important for improving our understanding of planet formation and evolution. Aims. We aim to determine the spatial gradients of exoplanet occurrence in the Solar neighbourhood and in the vicinity of open clusters. Methods. We combined Kepler and Gaia DR2 data for this purpose, splitting the volume sampled by the Kepler mission into certain spatial bins. We determined an uncorrected and bias-corrected exoplanet frequency and metallicity for each bin. Results. There is a clear drop in the uncorrected exoplanet frequency with distance for F-type stars (mainly for smaller planets), a decline with increasing distance along the Galactic longitude l = 90°, and a drop with height above the Galactic plane. We find that the metallicity behaviour cannot be the reason for the drop of the exoplanet frequency around F stars with increasing distance. This might have only contributed to the drop in uncorrected exoplanet frequency with the height above the Galactic plane. We argue that the above-mentioned gradients of uncorrected exoplanet frequency are a manifestation of a single bias of undetected smaller planets around fainter stars. When we correct for observational biases, most of these gradients in exoplanet frequency become statistically insignificant. Only a slight decline of the planet occurrence with distance for F stars remains significant at the 3σ level. Apart from that, the spatial distribution of exoplanets in the Kepler field of view is compatible with a homogeneous one. At the same time, we do not find a significant change in the exoplanet frequency with increasing distance from open clusters. In terms of byproducts, we identified six exoplanet host star candidates that are members of open clusters. Four of them are in the NGC 6811 (KIC 9655005, KIC 9533489, Kepler-66, Kepler-67) and two belong to NGC 6866 (KIC 8396288, KIC 8331612). Two out of the six had already been known to be cluster members.

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