The role of the interstellar extinction law and bandwidth effects in multicolor photometry

Sudzius, J.; Bobinas, V.; Raudeliunas, S.

doi:10.1515/astro-1996-0310

Cited by 3 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This renders the color estimate redshift-dependent. Assuming that the local extinction in the GRB environment is dominated by dust, we corrected the observed optical/NIR spectral slope of the afterglow by adopting a local optical extinction curve A(λ) in the GRB environment which is similar to that for the Galactic interstellar dust (Sūdžius, Bobinas, & Raudeliūnas 1996). However, we let the ratio of total-to-selective extinction, R dust , a free parameter, in order to describe approximately the various extinction curves found in star-forming regions in our Galaxy (e.g., Vrba, Coyne, & Tapia 1993) and in starburst galaxies (e.g., Calzetti 1997).…”

Section: Resultsmentioning

confidence: 99%

The Very Red Afterglow of GRB 000418: Further Evidence for Dust Extinction in a Gamma‐Ray Burst Host Galaxy

Klose

Stecklum

Masetti³

et al. 2000

ApJ

View full text Add to dashboard Cite

We report near-infrared and optical follow-up observations of the afterglow of the Gamma-Ray Burst 000418 starting 2.5 days after the occurrence of the burst and extending over nearly seven weeks. GRB 000418 represents the second case for which the afterglow was initially identified by observations in the near-infrared. During the first 10 days its R-band afterglow was well characterized by a single power-law decay with a slope of 0.86. However, at later times the temporal evolution of the afterglow flattens with respect to a simple power-law decay. Attributing this to an underlying host galaxy we find its magnitude to be R=23.9 and an intrinsic afterglow decay slope of 1.22. The afterglow was very red with R − K ≈4 mag. The observations can be explained by an adiabatic, spherical fireball solution and a heavy reddening due to dust extinction in the host galaxy. This supports the picture that (long) bursts are associated with events in star-forming regions.

show abstract

Section: Resultsmentioning

confidence: 99%

The Very Red Afterglow of GRB 000418: Further Evidence for Dust Extinction in a Gamma‐Ray Burst Host Galaxy

Klose

Stecklum

Masetti³

et al. 2000

ApJ

View full text Add to dashboard Cite

show abstract

“…right), which appears to be rather short for an early B-type star. Vilnius photometry (Sudzius & Bobinas 1992) and assuming a binary scenario with a massless companion and an orbital period of 0.67834 days requires a semimajor axis of R=7.6 R e , which is similar to the primary's radius. Alternative hypotheses would be SPBtype pulsation with a nonsinusoidal light curve (Kurtz et al 2015) or a base period that is twice as long.…”

Section: Other Nonsinusoidal and Unusual Behaviormentioning

confidence: 99%

New Beta Cephei Stars from the KELT Project

Labadie-Bartz

Handler

Pepper

et al. 2020

View full text Add to dashboard Cite

We present the results of a search for Galactic β Cephei stars, which are massive pulsating stars with both pressure modes and mixed modes. Thus, these stars can serve as benchmarks for seismological studies of the interiors of massive stars. We conducted the search by performing a frequency analysis on the optical light curves of known Oand B-type stars with data from the Kilodegree Extremely Little Telescope exoplanet survey. We identify 113 β Cephei stars, of which 86 are new discoveries, which altogether represent a 70% increase in the number currently known. An additional 97 candidates are identified. Among our targets, we find five new eclipsing binaries and 22 stars with equal frequency spacings suggestive of rotational splitting of nonradial pulsation modes. Candidates for runaway stars among our targets and a number of interesting individual objects are discussed. Most of the known and newly discovered β Cephei stars will be observed by the Transiting Exoplanet Survey Satellite mission, providing by far the most comprehensive observational data set of massive main-sequence pulsating stars of sufficient quality for detailed asteroseismic studies. Future analysis of these light curves has the potential to dramatically increase our understanding of the structure of stellar interiors and the physical processes taking place therein. Unified Astronomy Thesaurus concepts: Beta Cepheid variable stars (148); Asteroseismology (73); Stellar oscillations (1617); Multi-periodic variable stars (1079); Pulsating variable stars (1307); Short period variable stars (1453); Early-type variable stars (432); Light curves (918); Light curve classification (1954); Surveys (1671); B stars (128) Supporting material: data behind figure, machine-readable tables

show abstract

“…Integrating the T bCO (v) profile at the centre of the kernel of NRAO 655 over the same velocity range gives N H2 0.38 10 22 cm −2 . Then the visual extinction A v 5.3 10 −22 (N HI + 2N H2 ) (Savage & Mathis 1979), which gives A v 9.4 magnitudes or E(B − V ) = 2.96 (Sudzius et al 1996). This value for A v is ∼2 magnitudes larger than a similar estimate made by Vallée & Higgs (1985) in the direction ( , b) = (90.2, 1.7).…”

Section: Ionization Model Based On Free-free Radio Emission and Hα Emmentioning

confidence: 51%

The galactic plane region near $\mathsf{\ell=93^\circ}$

Foster

Routledge

2001

A&A

View full text Add to dashboard Cite

We present new Canadian Galactic Plane Survey radio continuum and λ21 cm HI line observations of NRAO 655 (G93.4+1.8), plus radio recombination line observations, and optical Hα-line observations. The radio spectrum of NRAO 655 confirms its emission as thermal. From the λ21 cm HI data we find an atomic hydrogen cavity associated with this object at v −71.5 km s −1. The cavity corresponds in position and size to the brightest radio continuum emission from NRAO 655. The corresponding kinematic distance is 8.8 kpc, placing NRAO 655 in the Perseus Arm. NRAO 655's linear size is therefore 70 pc × 130 pc. To confirm the λ21 cm HI velocity we present the first recombination line detection of NRAO 655 (H158α line, v −71 km s −1), and the first observations of a molecular cloud coinciding with NRAO 655 (at v −72 km s −1). The first optical detection of λ656 nm Hα emission line features in NRAO 655 is also presented, and the Hα emission line brightness is determined. We suggest that the eastward extension of this strongly asymmetric object originates in a champagne outflow, and we estimate its age. We show that a single early-type star cannot be responsible for the outflow, whereas a group of later-type stars would suffice. A partial HI shell is seen adjacent to the brightest part of NRAO 655; we suggest that it has been formed by dissociation of H2 in the molecular cloud.

show abstract

The role of the interstellar extinction law and bandwidth effects in multicolor photometry

Cited by 3 publications

References 0 publications

The Very Red Afterglow of GRB 000418: Further Evidence for Dust Extinction in a Gamma‐Ray Burst Host Galaxy

The Very Red Afterglow of GRB 000418: Further Evidence for Dust Extinction in a Gamma‐Ray Burst Host Galaxy

New Beta Cephei Stars from the KELT Project

The galactic plane region near $\mathsf{\ell=93^\circ}$

Contact Info

Product

Resources

About