DIFFUSE INTERSTELLAR BAND 6202 ˚ A AS AN INDICATOR OF ORGANIC MATTER IN COSMOS: CEPHEID SPECTRA

Автор(и)

  • S M. Andrievsky Astronomical Observatory, Odesa National University, Ukraine
  • A. Shereta Astronomical Observatory, Odesa National University, Ukraine
  • S. V, Khrapaty Department of Biophysics and Medical Informatics, National Taras Shevchenko University of Kyiv, Ukraine
  • S. A. Korotin Crimean Astrophysical Observatory, Ukraine
  • V. V. Kovtyukh Astronomical Observatory, Odesa National University, Ukraine
  • V. I. Kashuba Astronomical Observatory, Odesa National University, Ukraine

DOI:

https://doi.org/10.18524/1810-4215.2019.32.182049

Ключові слова:

classical cepheids, ISM lines and bands, ISM molecules, ISM structure

Анотація

We have described the method of
investigation of the diffuse interstellar band (DIB) at
6202
˚
A. This DIB is seen in the spectra of cepheid
stars, and it is blended with two stellar lines of Ce II
(6201.773
˚
A) and Ni I (6204.6
˚
A). After removal
of the blending lines of ionized cerium and neutral
nickel, we can determine the equivalent widths (EW)
of the DIB. This procedure can be applied for the
sample of cepheids (with well known distances), which
enables one to construct the map of the organic matter
distribution in the Galactic disc and use these values
to investigate the E(B–V)–DIB EW relation. The
relation found from Cepheids matches that found in B
stars. This relation can help to find the reddening for
newly discovered Cepheids without extensive photo-
metric data, and thus determine their distances. The
relation between E(B–V) and the DIB EW does not
yield precise reddening values. It is not a substitute
for better photometric or spectroscopic methods. At
best, it is indicative, but it provides some information
that may not be otherwise available.

Посилання

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Salama F., Ehrenfreund P.: 2014, The Diffuse Interstellar Bands, J. Cami & N.L.J. Cox, eds. Proc. IAU Symp. 297, 364.

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Опубліковано

2019-10-29

Номер

Розділ

Астрофізика (зоряні атмосфери, взаємодіючі подвійні системи, змінні зорі)