Limits to Ionization-parameter Mapping as a Diagnostic of Hii Region Optical Depth

Evaluation of dosimetry a performance parameter for a homemade farmer-type ionization chamber according to IEC60731

Introduction: Due to its simplicity, fast response and high reliability, ion chamber detectors are one of the most suitable dosimetry instruments for X and gamma rays. The dosimeter    of photon beams, which used in radiotherapy centers, requires high accuracy and should pass requirements of IEC 60731 standards. About 80 percent of the IEC 60731 standard tests such as stabil...

[NeIII]/[OII] as an Ionization Parameter Diagnostic in Star-Forming Galaxies

We present our parameterizations of the log([NeIII]λ3869/[OII]λ3727) (Ne3O2) and log([OIII]λ5007/[OII]λ3727) (O3O2) ratios as comparable and effective diagnostics of ionization parameter in star-forming galaxies. Our calibrations are based on the most recent generations of the Starburst99/Mappings III photoionization models, which extend up to the extremely high values of ionization parameter f...

Network Mapping as a Diagnostic Tool

Physical Conditions in the Orion HII Region

The Orion Nebula is the defining galactic HII Region, and has been well studied over a broad range of wavelengths. Many of its properties are well established. The gas-phase metallicity is roughly 2/3 of solar, close to that of the star cluster. There is no evidence that grains are destroyed anywhere in the Orion environment; refractory elements such as Ca and Fe remain heavily depleted. If the...

Sample of minor merger of galaxies : Optical CCD surface photometry and HII region properties

We present the results of the B, V and I photometry of eleven southern minor mergers. The total apparent B magnitude, integrated B-V and V-I colours were measured. We built B, V, and I equivalent profiles for each galaxy and decomposed them into bulge and disk components when possible. From Hα+N[II] images we have estimated the basic photometric parameters of the HII regions, such as position, ...