The H I supershell GS 118+01-44 and its role in the interstellar medium

CICHOWOLSKI SILVINA; TESTORI JUAN CARLOS; NORIEGA-CRESPO ALBERTO; FLAGEY NICOLAS; SUAD LAURA ANDREA; ARNAL E. MARCELO

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Lugar: Paris; Año: 2016 vol. 585

0004-6361

Aims: We carry out a multiwavelength study to characterize the HI supershell designated GS 118+01-44, and to analyse its possibleorigin. Methods: A multiwavelength study has been carried out tostudy the supershell and its environs. We performed an analysis of the HI, CO, radio continuum, and infrared emission distributions. Results: The Canadian Galactic Plane Survey (CGPS) H I data reveals thatGS 118+01-44 is centred at (l,b) = (117°&dotbelow;7,1°&dotbelow;4) with a systemic velocity of -44.3 km s-1.According to Galactic rotation models this structure is located at 3.0± 0.6 kpc from the Sun. There are several H II regions and threesupernova remnants (SNRs) catalogued in the region. On the other hand,the analysis of the temperature spectral index distribution shows thatin the region there is a predominance of non-thermal emission. Infraredemission shows that cool temperatures dominate the area of thesupershell. Concerning the origin of the structure, we found that eventhough several OB stars belonging to Cas OB5 are located in the interiorof GS 118+01-44, an analysis of the energy injected by these starsthrough their stellar winds indicates that they do not have sufficientenergy to create GS 118+01-44. Therefore, an additional energy source isneeded to explain the genesis of GS 118+01-44. On the other hand, thepresence of several H II regions and young stellar object candidates inthe edges of GS 118+01-44 shows that the region is still active informing new stars.