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Related papers: Optimal extinction measurements - I. Single-object…

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Dust extinction is the most robust tracer of the gas distribution in the interstellar medium, but measuring extinction is limited by the systematic uncertainties involved in estimating the intrinsic colors to background stars. In this paper…

Instrumentation and Methods for Astrophysics · Physics 2017-05-24 Stefan Meingast , Marco Lombardi , Joao Alves

We consider from a general point of view the problem of determining the extinction in dense molecular clouds. We use a rigorous statistical approach to characterize the properties of the most widely used optical and infrared techniques,…

Astrophysics · Physics 2009-11-11 Marco Lombardi

We generalize the technique of Lada et al. (1994) to map dust column density through a molecular cloud (NICE) to an optimized multi-band technique (NICER) that can be applied to any multi-band survey of molecular clouds. We present a first…

Astrophysics · Physics 2009-11-07 Marco Lombardi , Joao Alves

Several methods exist to convert near-infrared (NIR) stellar observations into extinction maps. We present a new method based on NIR multiband observations. The method uses a discretised version of the distribution of intrinsic stellar…

Astrophysics of Galaxies · Physics 2016-01-13 M. Juvela , J. Montillaud

Extinction remains one of the most reliable methods of measuring column density of nearby Galactic interstellar clouds. The current and ongoing near-infrared surveys enable the mapping of extinction over large sky areas. We produce allsky…

Astrophysics of Galaxies · Physics 2015-12-16 M. Juvela , J. Montillaud

Dust plays a critical role in the study of the interstellar medium (ISM). Extinction maps derived from optical surveys often fail to capture regions with high column density due to the limited photometric depth in optical wavelengths. To…

Astrophysics of Galaxies · Physics 2025-10-17 Miaomiao Zhang , Jouni Kainulainen , He Zhao , Yang Su , Min Fang , Yuehui Ma , Zhiwei Chen , Zhibo Jiang

Observational data and theoretical calculations show that significant small-scale substructures are present in dark molecular clouds. These inhomogeneities can provide precious hints on the physical conditions inside the clouds, but can…

Astrophysics · Physics 2009-11-13 Marco Lombardi

We propose a general method for mapping the extinction in dense molecular clouds using 2MASS near-infrared data. The technique is based on the simultaneous utilization of star counts and colors. These two techniques provide independent…

Astrophysics · Physics 2009-11-07 L. Cambresy , C. A. Beichman , T. H. Jarrett , R. M. Cutri

We propose an improved method for the atmospheric extinction reduction within optical photometry. Our method is based on the simultaneous multicolor observations of photometric standards. Such data are now available within the modern…

Instrumentation and Methods for Astrophysics · Physics 2015-10-06 A. Zakharov , A. Mironov , A. Biryukov , N. Kroussanova , M. Prokhorov , G. Beskin , S. Karpov , S. Bondar , E. Ivanov , A. Perkov , V. Sasyuk

Using deep J, H and Ks-band observations, we have studied the near-infrared (nIR) extinction of the Nuclear Bulge (NB) and we find significant, complex variations on small physical scales. We have applied a new variable nIR colour excess…

Astrophysics of Galaxies · Physics 2009-11-13 Andrew J. Gosling , Reba M. Bandyopadhyay , Katherine M. Blundell

The near infrared extinction powerlaw index ($\beta$) and its uncertainty is derived from three different techniques based on star counts, colour excess and a combination of them. We have applied these methods to 2MASS data to determine…

Astrophysics · Physics 2009-11-11 Dirk Froebrich , Carlos del Burgo

We present a three dimensional extinction map in $r$ band. The map has a spatial angular resolution, depending on latitude, between 3 -- 9\,arcmin and covers the entire XSTPS-GAC survey area of over 6,000\,$\rm deg^2$ for Galactic longitude…

Solar and Stellar Astrophysics · Physics 2015-06-22 B. -Q Chen , X. -W. Liu , H. -B. Yuan , H. -H. Zhang , M. Schultheis , B. -W. Jiang , Y. Huang , M. -S. Xiang , H. -B. Zhao , J. -S. Yao , H. Lu

Atmospheric lidar observations provide a unique capability to directly observe the vertical column of cloud and aerosol scattering properties. Detector and solar background noise, however, hinder the ability of lidar systems to provide…

Optimization and Control · Mathematics 2016-06-21 Willem J. Marais , Robert E. Holz , Yu Hen Hu , Ralph E. Kuehn , Edwin E. Eloranta , Rebecca M. Willett

Density estimation is a fundamental problem that arises in many areas of astronomy, with applications ranging from selecting quasars using color distributions to characterizing stellar abundances. Astronomical observations are inevitably…

Instrumentation and Methods for Astrophysics · Physics 2024-12-05 Yi Kang , Joseph F. Hennawi , Jan-Torge Schindler , John Tamanas , Riccardo Nanni

We present a general expression for the optical theorem in terms of Localized Waves. This representation is well-known and commonly used to generate Frozen waves, Xwaves, and other propagation invariant beams. We analyze several examples…

Optics · Physics 2022-01-12 Irving Rondon

Dust extinction is one of the most reliable tracers of the gas distribution in the Milky Way. The near-infrared (NIR) Vista Variables in the Via Lactea (VVV) survey enables extinction mapping based on stellar photometry over a large area in…

Astrophysics of Galaxies · Physics 2022-11-16 Miaomiao Zhang , Jouni Kainulainen

Using near infrared UKIDSS Galactic Plane Survey data, we make extinction measurements to individual stars along the same line of sight as molecular clouds. Using an existing 3D extinction map of the inner Galaxy, that provides line of…

Astrophysics of Galaxies · Physics 2015-05-18 J. J. Stead , M. G. Hoare

We present a comprehensive study of interstellar X-ray extinction using the extensive Chandra supernova remnant archive and use our results to refine the empirical relation between the hydrogen column density and optical extinction. In our…

High Energy Astrophysical Phenomena · Physics 2016-07-27 Dillon Foight , Tolga Guver , Feryal Ozel , Patrick Slane

Context. The properties of dust grains, in particular their size distribution, are expected to differ from the interstellar medium to the high-density regions within molecular clouds. Since the extinction at near-infrared wavelengths is…

Astrophysics of Galaxies · Physics 2015-06-04 Joana Ascenso , Marco Lombardi , Charles J. Lada , João Alves

We present a new method for deriving UV-through-IR extinction curves, based on the use of stellar atmosphere models to provide estimates of the intrinsic (i.e., unreddened) stellar spectral energy distributions (SEDs), rather than…

Astrophysics · Physics 2008-11-26 Edward L. Fitzpatrick , Derck Massa
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