J/ApJ/874/172 H_2_CO & H110{alpha} obs. toward Aquila (Komesh+, 2019) ================================================================================ H_2_CO and H110{alpha} observations toward the Aquila Molecular Cloud. Komesh T., Esimbek J., Baan W., Zhou J., Li D., Wu G., He Y., Sailanbek S., Tang X., Manapbayeva A. =2019ApJ...874..172K ================================================================================ ADC_Keywords: Molecular clouds; Interstellar medium; Radio lines Keywords: ISM: molecules ; stars: formation Abstract: The formaldehyde H_2_CO(1_10_-1_11_) absorption line and H110{alpha} radio recombination line have been observed toward the Aquila Molecular Cloud using the Nanshan 25m telescope operated by the Xinjiang Astronomical Observatory CAS. These first observations of the H_2_CO (1_10_-1_11_) absorption line determine the extent of the molecular regions that are affected by the ongoing star formation in the Aquila molecular complex and show some of the dynamic properties. The distribution of the excitation temperature Tex for H_2_CO identifies the two known star formation regions W40 and Serpens South as well as a smaller new region Serpens 3. The intensity and velocity distributions of H_2_CO and ^13^CO(1-0) do not agree well with each other, which confirms that the H_2_CO absorption structure is mostly determined by the excitation of the molecules resulting from the star formation rather than by the availability of molecular material as represented by the distribution. Some velocity-coherent linear ^13^CO(1-0) structures have been identified in velocity channel maps of H2CO and it is found that the three star formation regions lie on the intersect points of filaments. The H110{alpha} emission is found only at the location of the W40 HII region and spectral profile indicates a redshifted spherical outflow structure in the outskirts of the HII region. Sensitive mapping of H_2_CO absorption of the Aquila Complex has correctly identified the locations of star formation activity in complex molecular clouds and the spectral profiles reveal the dominant velocity components and may identify the presence of outflows. Description: The H_2_CO (1_10_-1_11_) absorption line ({lambda}=6cm, v0=4829.6594MHz) and the H110{alpha} radio recombination line (RRL) (v0=4874.1570MHz) have been observed in the Aquila Molecular Cloud during 2015 February using the Nanshan 25m radio telescope of the Xinjiang Astronomical Observatory of the Chinese Academy of Sciences. Objects: ---------------------------------------------------------- RA (ICRS) DE Designation(s) ---------------------------------------------------------- 18 30 03 -02 02 40 AMC = NAME Aquila Cloud ---------------------------------------------------------- File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table1.dat 72 182 Parameters of the H_2_CO (1_10_-1_11_) absorption line -------------------------------------------------------------------------------- See also: J/A+A/551/A28 : H2CO and CO in 4 molecular clouds (Tang+, 2013) J/A+A/584/A91 : Catalog of dense cores in Aquila from Herschel (Konyves+, 2015) J/ApJS/219/21 : Deep NIR survey toward Aquila. I. MHOs (Zhang+, 2015) Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 3 I3 arcmin oRA [-30/40] Offset in RA (1) 5- 7 I3 arcmin oDE [-30/40] Offset in DE (1) 9- 15 F7.4 K.km/s Flux [-1.11/-0.06] Flux density 17- 20 F4.2 K.km/s e_Flux [0.01/0.05] Uncertainty in Flux 22- 26 F5.3 km/s Vel [5.3/8.7] Velocity 28- 31 F4.2 km/s e_Vel [0.03/0.6] Uncertainty in Velocity 33- 37 F5.3 km/s Width [1.3/9.41] Width 39- 42 F4.2 km/s e_Width [0.07/2] Uncertainty in Width 44- 49 F6.3 K TL [-0.33/-0.03] Absorption line antenna temperature 51- 55 F5.3 K TC [0.004/3.33]? Continuum brightness 57- 61 F5.2 --- tau [-0.3/0.62] Optical depth 63- 67 F5.2 10+12/cm2 N(H2CO) [1.96/18.7] H_2_CO column density 69- 72 F4.2 K Tex [0.18/4.8] Excitation temperature -------------------------------------------------------------------------------- Note (1): The central position is RA:18:30:03, DEC:-2:02:40 (Eq=J2000). -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Prepared by [AAS], Emmanuelle Perret [CDS] 02-Sep-2020