Araya, E. D.E. D.ArayaOLMI, LUCALUCAOLMIMorales Ortiz, J.J.Morales OrtizBrown, J. E.J. E.BrownHofner, P.P.HofnerKurtz, S.S.KurtzLinz, H.H.LinzCreech-Eakman, M. J.M. J.Creech-Eakman2020-04-142020-04-1420150004-637Xhttp://hdl.handle.net/20.500.12386/24009The detection of four formaldehyde (H<SUB>2</SUB>CO) maser regions toward young high-mass stellar objects in the last decade, in addition to the three previously known regions, calls for an investigation of whether H<SUB>2</SUB>CO masers are an exclusive tracer of young high-mass stellar objects. We report the first survey specifically focused on the search for 6 cm H<SUB>2</SUB>CO masers toward non high-mass star-forming regions (non HMSFRs). The observations were conducted with the 305 m Arecibo Telescope toward 25 low-mass star-forming regions, 15 planetary nebulae and post-AGB stars, and 31 late-type stars. We detected no H<SUB>2</SUB>CO emission in our sample of non HMSFRs. To check for the association between high-mass star formation and H<SUB>2</SUB>CO masers, we also conducted a survey toward 22 high-mass star-forming regions from a Hi-GAL (Herschel infrared Galactic Plane Survey) sample known to harbor 6.7 GHz CH<SUB>3</SUB>OH masers. We detected a new 6 cm H<SUB>2</SUB>CO emission line in G32.74-0.07. This work provides further evidence that supports an exclusive association between H<SUB>2</SUB>CO masers and young regions of high-mass star formation. Furthermore, we detected H<SUB>2</SUB>CO absorption toward all Hi-GAL sources, and toward 24 low-mass star-forming regions. We also conducted a simultaneous survey for OH (4660, 4750, 4765 MHz), H110α (4874 MHz), HCOOH (4916 MHz), CH<SUB>3</SUB>OH (5005 MHz), and CH<SUB>2</SUB>NH (5289 MHz) toward 68 of the sources in our sample of non HMSFRs. With the exception of the detection of a 4765 MHz OH line toward a pre-planetary nebula (IRAS 04395+3601), we detected no other spectral line to an upper limit of 15 mJy for most sources.STAMPAenArticle10.1088/0067-0049/221/1/102-s2.0-84948772849000366620600010https://iopscience.iop.org/article/10.1088/0067-0049/221/1/102015ApJS..221...10AFIS/05 - ASTRONOMIA E ASTROFISICA