A family of cometary globules at the periphery of Cyg OB1: the star HBHA 3703-01 and the reflection nebula GM 2-39

TL;DR

This study analyzes a family of cometary globules near Cyg OB1, identifying the star HBHA 3703-01 as a Herbig Ae/Be star illuminating the nebula GM 2-39, and explores their structure, gas dynamics, and ionization sources.

Contribution

It provides a comprehensive multi-wavelength analysis of the globules and identifies the nature of the central star HBHA 3703-01 as a Herbig Ae/Be star, linking it to the globules' formation and illumination.

Findings

Detection of a CO cavern around the globules

Identification of HBHA 3703-01 as a Herbig Ae/Be star

Modeling of the star's spectral energy distribution

Abstract

The interstellar medium in the region of a family of cometary globules including the reflection nebula GM 2-39 has been analyzed basing on our observations with the slit spectrograph, the results of our previous observations with a Fabry-Perot interferometer in the H-alpha line, Spitzer archival data together with CO microwave data. The structure of globules' IR emission, velocity field of ionized gas in the H-alpha line and of molecular gas in the CO line have been considered. We have detected a CO cavern around the eastern globules and faint high-velocity H-alpha features of surrounding gas. The most probable sources of ionizing radiation and wind of the Cyg OB1 association responsible for the globules' formation are proposed. Based on our multicolour photometry, it has been found that the brightest compact source in the southern 'head' of the cometary globule - the star HBHA 3703-01 (IRAS 20153+3850) - is a B(5-6)V star with E(B-V)=1.18 mag. The strong and broad H-alpha emission line was revealed in its spectrum. The spectral energy distribution of HBHA 3703-01 in the 0.44-24 micron range has been modeled. It is shown that the star has a hot dust envelope with T(dust)=1400 K and tau(V)=1.1. Besides, the star HBHA 3703-01 illuminates the encompassing diffuse nebula GM 2-39 with a diameter of about 30 arcsec. With regard to all obtained observational data for HBHA 3703-01, this object may be classified as the Herbig Ae/Be star.